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Preprint ARTICLE | doi:10.20944/preprints202404.1911.v1

Understanding Preferences of Indian Three-Wheeler Drivers for Electric Vehicles

Zijin Zhou, Lingfang Shao

Subject: Architecture, Building And Construction, Engineering Keywords: Electric three-wheeler; Intermediate Public Transport (IPT); Discrete Choice Model; Driver Preferences; Transition Challenges; Market Penetration Strategies

Online: 29 April 2024 (10:07:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202310.0773.v18

Resolving the Collatz Conjecture: A Rigorous Proof through Inverse Discrete Dynamical Systems and Algebraic Inverse Trees

Eduardo Diedrich

Subject: Mathematics, Computer Science And Mathematics Keywords: discrete dynamical systems; inverse modeling; topological equivalence; topological transport; algebraic trees; collatz conjecture; homeomorphic invariance

Online: 29 April 2024 (09:46:13 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202404.1704.v1

Vision System for the Mars Sample Return Capture, Containment and Return System (CCRS)

Brent Jon Bos, David Donovan, John Capone, Chen Wang, Terra Hardwick, Dylan Bell, Yuqing Zhu, Robert Podgurski, Bashar Rizk, Ireneusz Orlowski, Rachel Edison, David Harvey, Brianna Dizzon, Lindsay Haseltine, Kristoffer Olsen, Chad Sheng, Robert Bousquet, Luan Vo, Georgi Georgiev, Kristen Washington, Michael Singer, Stefan Ioana, Anloc Le, Elena Georgieva, Michael Hackett, Michael Ravine, Michael Caplinger, Phillip Coulter, Erin Percy, Charles Torisky, Jean Lauenstein, Kaitlyn Ryder, Michael Campola, Dillon Johnstone, William J. Thomes, Richard G. Schnurr, John McCloskey, Eugenia DeMarco, Ellen Lee, Calinda Yew, Bo Yang, Mingyu Han, Bartosz Blonski

Subject: Aerospace Engineering, Engineering Keywords: Mars; cameras; sample return; space optics

Online: 26 April 2024 (09:33:12 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202404.0727.v1

Analyzing Bifurcations and Optimal Control Strategies in SIRS Epidemic Models: Insights from Theory and COVID-19 Data

Mohamed Cherif Belili, Mohamed Lamine Sahari, Omar Kebiri, Halim Zeghdoudi

Subject: Computer Science And Mathematics, Applied Mathematics Keywords: Flip bifurcation; Transcritical bifurcation; discrete epidemic model; numerical simulation

Online: 10 April 2024 (11:45:15 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202404.0081.v1

Error Model of the Measurement Chain Containing the Discrete Wavelet Transform Algorithm

Marian Kampik, Jerzy Roj, Łukasz Dróżdż

Subject: Computer Science And Mathematics, Signal Processing Keywords: measurement chain error model; uncertainty estimation; discrete wavelet transform

Online: 2 April 2024 (02:27:20 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202403.1259.v1

Application of the Discrete Wavelet Transform to Damage Detection in a Guy Cable of Guyed Antenna Mast

Anna Knitter-Piątkowska, Maciej Przychodzki, Michał Guminiak

Subject: Engineering, Civil Engineering Keywords: truss steel mast; guy ropes; finite element method; damage detection; discrete wavelet transform

Online: 21 March 2024 (08:20:12 CET)

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Preprint ARTICLE | doi:10.20944/preprints202403.0702.v1

Convergence in Discrete Inverse Dynamical Systems

Eduardo Diedrich

Subject: Computer Science And Mathematics, Security Systems Keywords: Discrete dynamical systems; Inverse modeling; Topological equivalence; Topological transport; Algebraic trees; Combinatorial explosions; Computational complexity; Universal convergence

Online: 17 March 2024 (15:58:52 CET)

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Preprint ARTICLE | doi:10.20944/preprints202403.0877.v1

Study on the Macro-Fine Mechanical Behavior of Ores Flow Based on Discrete Element Method

Zhiguo Xia, Zhe Deng, Zengxiang Lu, Chenglong Ma

Subject: Engineering, Mining And Mineral Processing Keywords: ore storage section of orepass; discrete element method; ore-rock flow characteristics; lateral pressure of shaft wall; wall damage degree

Online: 15 March 2024 (14:41:00 CET)

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Preprint ARTICLE | doi:10.20944/preprints202403.0734.v1

Comparative Effectiveness of Supervised and Home-based Rehabilitation after Anterior Cruciate Ligament Reconstruction in Competitive Athletes

Rehan Iftikhar Bukhari Syed, Laszlo Rudolf Hangody, Gergely Frischmann, Petra Kós, Bence Kopper, Berkes István

Subject: Public Health And Healthcare, Physical Therapy, Sports Therapy And Rehabilitation Keywords: anterior cruciate ligament; anterior cruciate ligament reconstruction; supervised rehabilitation; Home-based rehabilitation; return to sport; prevention; re-injury

Online: 13 March 2024 (11:36:56 CET)

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Preprint ARTICLE | doi:10.20944/preprints202403.0142.v1

Non-Union Treatment in the Foot, Ankle, and Lower Leg: A Multicenter Retrospective Study Comparing Conventional Treatment with the Human Allogeneic Cortical Bone Screw (Shark Screw®)

Viktor Labmayr, Elisabeth Huber, Florian Wenzel-Schwarz, Patrick Holweg, Martin Ornig, Gerd Jakob, Wolfgang Palle, Gudrun H. Borchert, Klaus Pastl

Subject: Medicine And Pharmacology, Orthopedics And Sports Medicine Keywords: bone healing; non-union; human allogeneic cortical bone screw; Shark Screw®; ; allograft; pseudarthrosis; foot and ankle; time to union; delayed union; return to work; hardware removal; health care costs

Online: 4 March 2024 (14:04:54 CET)

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Preprint ARTICLE | doi:10.20944/preprints202402.0967.v1

Intelligence and the Value of Forensic Science

Paul J Speaker

Subject: Business, Economics And Management, Business And Management Keywords: Forensic Intelligence; Cost-Benefit; Return on Investment; Front-end Forensics

Online: 19 February 2024 (11:49:02 CET)

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Preprint ARTICLE | doi:10.20944/preprints202402.0497.v1

Optimal Opacity-Enforcing Supervisory Control of Discrete Event Systems on Choosing Cost

Yinyin Dai, Fei Wang, Jiliang Luo

Subject: Engineering, Control And Systems Engineering Keywords: Opacity; optimal supervisors; dynamic programming; discrete event systems

Online: 8 February 2024 (07:03:01 CET)

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Preprint ARTICLE | doi:10.20944/preprints202402.0280.v1

General Relativistic Hydrodynamics in Discrete Spacetime: Perfect Fluid Accretion onto Static and Spinning Black Holes

Jonathan Gorard

Subject: Physical Sciences, Mathematical Physics Keywords: General Relativity; Relativistic Hydrodynamics; Discrete Spacetime; Black Hole Accretion

Online: 5 February 2024 (15:35:16 CET)

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We study the problem of a spherically-symmetric distribution of a perfect relativistic fluid accreting onto a (potentially spinning) black hole within a fully discrete spacetime setting. This problem has previously been studied extensively in the context of continuum spacetimes, beginning with the purely analytic work of Bondi in the spherically-symmetric Newtonian case, Michel in the spherically-symmetric general relativistic case, and Petrich, Shapiro and Teukolsky in the axially-symmetric general relativistic case relevant for spinning black holes. However, the purpose of the present work is to determine the effect of discretization of the underlying spacetime upon the mass/energy and momentum accretion rates, the overall morphology and characteristics of the accretion flow, and the drag force exerted on the black hole in the case of non-zero spin. In order to achieve this, we first develop a novel formulation of the equations of general relativistic hydrodynamics that is more directly amenable to rigorous analysis within a discrete spacetime setting, and we then proceed to implement this formulation into the \textsc{Gravitas} computational general relativity framework. Through a combination of mathematical analysis and explicit numerical simulation in \textsc{Gravitas}, we discover that the mass/energy and momentum accretion rates both decrease monotonically as functions of the underlying spacetime discretization scale, with this effect becoming more pronounced for higher values of the black hole spin parameter, higher fluid temperatures, and stiffer equation of state parameters. We also find that the exerted drag force is highly sensitive to the value of the underlying discretization scale in the case of spinning black hole spacetimes, with certain instabilities becoming significantly more pronounced at certain critical values of the discretization parameter. We discuss some potentially observable consequences of these results, as well as some directions for future theoretical investigation.

Preprint ARTICLE | doi:10.20944/preprints202402.0238.v1

General Divisibility Algorithms

Can Kaan KAYA

Subject: Computer Science And Mathematics, Algebra And Number Theory Keywords: Arithmetic Functions; Discrete Mathematics; Primes; Number Theory

Online: 5 February 2024 (08:02:06 CET)

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Preprint ARTICLE | doi:10.20944/preprints202402.0028.v1

Covid-19 and Uncertainty Effects on Tunisian Stock Market Volatility: Insights from GJR-GARCH, Wavelet Coherence, and ARDL

Emna Trabelsi

Subject: Business, Economics And Management, Finance Keywords: Stock return volatility; COVID-19; Uncertainty; GARCH; Bias-corrected Wavelet coherence analysis; ARDL

Online: 2 February 2024 (06:03:48 CET)

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Preprint ARTICLE | doi:10.20944/preprints202401.1553.v1

Research on the Terrain Characteristics of Changbai Mountain and Its Impact on Precipitation and Wind Distribution

Li Liang, Wanxiu Ai, Xiaodan Yang, Luqiang Zhao

Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: Changbai Mountain; two-dimensional discrete cosine transform; terrain spectra; wind spectra; precipitation spectra; additive synthesis; the dominant wavelength

Online: 22 January 2024 (05:48:35 CET)

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The terrain of Changbai Mountain has great influence on the distribution of atmospheric flows and the occurrence and development of precipitation. This study quantitatively analyzes the regional characteristic of topographic perturbations and the relationship between terrain, wind and precipitation in Changbai Mountain region, by using a spectral analysis of the two-dimensional discrete cosine transform. Three domains with relatively heavy summer precipitation are selected as the study region. The results indicate that the overall terrain of Changbai Mountain region exhibits anisotropic characteristics. The terrain spectra of domain B are less than those of domain A and C across the whole wavelength (λ) bands, indicating that the large-scale topographic perturbations of domain B are relatively weak. The largest topographic spectral peak of domain C shows the most pronounced undulation of terrain among the three domains. The dominant wavelengths of terrain height variance for domain A and C, both close to the respective maximum wavelengths, indicate more prominent large-scale topographic perturbations. For domain A, the variation of the precipitation spectra is consistent with that of the wind spectra at the wavelength bands of λ < 390 km, showing a high correlation between wind field and the occurrence of rainfall. The inverse relationship at larger wavelengths indicates that multiple factors contribute to the occurrence of rainfall. For domain B, there is consistency in the fluctuations of terrain spectra, precipitation spectra, and wind spectra at the wavelength bands of λ < 278.3 km, implying that the smaller-scale terrain has an important effect on the occurrence of summer precipitation. For domain C, the variations of terrain spectra, precipitation spectra, and wind spectra are almost consistent across the whole wavelength bands, indicating that the large-scale terrain and minor terrain both play a crucial role in atmospheric uplift and the occurrence and development of summer rainfall.

Preprint ARTICLE | doi:10.20944/preprints202401.1162.v1

Economic Analysis of Agarwood Cultivation in Assam, India: An Empirical Investigation

Pranjal Protim Buragohain, Anshumi Dutta

Subject: Business, Economics And Management, Economics Keywords: agarwood; economic viability; net present value; benefit cost ratio; internal rate of return; Upper Assam

Online: 16 January 2024 (09:40:34 CET)

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Preprint ARTICLE | doi:10.20944/preprints202401.0714.v1

On the Dual Ontological Structure and Mixed Dynamics of the Universe

Dennis Kahan

Subject: Physical Sciences, Quantum Science And Technology Keywords: Arrow of time; heat death; 4D Spacetime; Homogeneity; Isotropy; quantum mechanics; wave function collapse; special relativity; high dimensional space; entropy; mixed ontology; singularity; discrete spacetime

Online: 9 January 2024 (10:12:49 CET)

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Preprint ARTICLE | doi:10.20944/preprints202312.1408.v1

Fractal Evolution Characteristics of Isolation Layers in Submarine Gold Mine: A Case Study

Yin Chen, Zijun Li, Weixing Lin, Yan He, Guoqiang Wang, Renze Ou, Qi Liu

Subject: Engineering, Mining And Mineral Processing Keywords: undersea mining; isolation layer; discrete element method; fracture fractal dimension

Online: 19 December 2023 (09:01:49 CET)

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Preprint ARTICLE | doi:10.20944/preprints202311.0990.v1

Discrete-Analog Low-Pass Filter Using Switched Capacitors With Resistive Pole Frequency Control

Nikolay Butyrlagin, Alexey Titov, Daria Denisenko, Yuri Ivanov

Subject: Engineering, Electrical And Electronic Engineering Keywords: discrete-analog low-pass filter; switched capacitors; transient process; second-order transfer function; operational amplifier; electronic switch; micro-Cap

Online: 15 November 2023 (10:05:18 CET)

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Preprint ARTICLE | doi:10.20944/preprints202311.0457.v1

Transition to the Fluid Dynamic Limit: Mathematical Models and Simulation Results

Hans Babovsky

Subject: Physical Sciences, Fluids And Plasmas Physics Keywords: Fluid dynamic limit; kinetic models; closure relations; discrete velocity simulations

Online: 8 November 2023 (01:35:51 CET)

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Preprint REVIEW | doi:10.20944/preprints202311.0380.v1

Fifteen Years after the Definition of Trypanosoma cruzi DTUs: What Have We Learned?

Bianca Zingales, Andréa M Macedo

Subject: Biology And Life Sciences, Other Keywords: Trypanosoma cruzi; Discrete Typing Units; genomics; Chagas disease manifestations; ecoepidemiology

Online: 7 November 2023 (11:40:14 CET)

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Preprint ARTICLE | doi:10.20944/preprints202311.0403.v1

Attitudes towards the environment and their impact on preferences for sustainable tourism products

Tim Fichter, Juan Carlos Martin, Concepcion Roman

Subject: Business, Economics And Management, Business And Management Keywords: Sustainable tourism; Active tourism; Hybrid Choice Model; Discrete Choice Experiment; Willingness to pay; Tourism demand

Online: 7 November 2023 (10:19:04 CET)

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Preprint ARTICLE | doi:10.20944/preprints202311.0379.v1

Unveiling the Nexus: Exploring the Impact of Corporate Governance on the Financial Performance of Acquiring Companies in the Indian Context

Debi Prasad Satpathy, Tarun Kumar Soni

Subject: Arts And Humanities, Humanities Keywords: Corporate governance; event study; firm performance; abnormal return; merger and acquisition

Online: 7 November 2023 (07:11:59 CET)

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Preprint ARTICLE | doi:10.20944/preprints202311.0272.v1

Almost Automorphic Solutions to Nonlinear Difference Equations

Marko Kostić, Halis Can Koyuncuoglu, Vladimir E. Fedorov

Subject: Computer Science And Mathematics, Analysis Keywords: discrete almost automorphic; discrete bi-almost automorphic; fixed point; contraction; Bohr-Neugebauer

Online: 6 November 2023 (03:08:22 CET)

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Preprint ARTICLE | doi:10.20944/preprints202310.1696.v1

Tensor Conjugate-Gradient Methods With Automatically Determination of Regularization Parameters for Ill-Posed Problems With T-product

Shi-Wei Wang, Guang-Xin Huang, Feng Yin

Subject: Computer Science And Mathematics, Computational Mathematics Keywords: linear discrete ill-posed problems; tensor Conjugate-Gradient method; t-product; discrepancy principle; Tikhonov regularization

Online: 26 October 2023 (11:09:51 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202310.1134.v1

Techno-economic Feasibility Study of a 1.5 MW Grid-connected Solar Power Plant in Bangladesh

Md. Feroz Ali, Nitai Kumar Sarker, Md. Alamgir Hossain, Shafiul Alam, Ashraf Hossain Sanvi, Syed Ibn Sifat

Subject: Engineering, Electrical And Electronic Engineering Keywords: carbon footprint; performance ratio; photovoltaic array system; PVsyst software; panel orienta-tion; levelized cost of electricity/energy (LCOE); payback period; return on investment (ROI); cost-effectiveness; project lifespan

Online: 18 October 2023 (08:12:42 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202310.0467.v1

Extruder Machine Gear Fault Detection Using Autoencoder LSTM via Senor Fusion Approach

Joon-Hyuk Lee, Chibuzo Nwabufo Okwuosa, Jang-Wook Hur

Subject: Engineering, Industrial And Manufacturing Engineering Keywords: Anomaly detection; autoencoder; long short-term memory; deep learning; discrete wavelet transform, feature extraction, outlier detection.)

Online: 9 October 2023 (07:34:29 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202309.1801.v1

Dynamics of the Capillary Lactate Levels in Patients with Out-of-Hospital Cardiac Arrest

Vitka Vujanović, Vesna Borovnik Lesjak, Dušan Mekiš, Matej Strnad

Subject: Medicine And Pharmacology, Emergency Medicine Keywords: cardiopulmonary resuscitation, out-of-hospital cardiac arrest, lactate, return of spontaneous circulation

Online: 28 September 2023 (02:50:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202309.0871.v1

Vibration Response of Soil under Low-Frequency Vibration Using Discrete Element Method

Lipengcheng Wan, Yonglei Li, Jinyu Song, Xiang Ma, Xiangqian Dong, Chao Zhang, Jiannong Song

Subject: Environmental And Earth Sciences, Soil Science Keywords: soil; low-frequency; discrete element method; vibration response; transmission

Online: 13 September 2023 (10:15:42 CEST)

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The vibration response of soil is a key property in the field of agricultural soil tillage. Vibration components of tillage machinery are generally used to reduce tillage resistance and improve work efficiency, the pressure variation under low-frequency vibration will affect the fragmentation and dispersion of farmland soil. However, the gradient of pressure variation, frequency domain response, and effective transmission range are unclear. A new method based on DEM (Discrete Element Method) is presented to study the vibration response and pressure transmission under low-frequency vibration. Bench test results showed that peak pressure positively correlates with the vibration frequency and attenuates rapidly at the vibration distance of 100 to 250 mm. The results data were also selected to determine the simulation model parameters. Amplitude, vibration frequency, and soil depth were used as test factors in single-factor simulation tests, and their effects on the peak pressure, frequency domain response, and effective transmission distance were analyzed. The results showed a positive relationship between the peak pressure and the test factors. The peak pressure increases with a maximum gradient of 19.02 kPa/mm at a vibration distance of 50 mm. The amplitude, vibration frequency, and soil depth positively correlate with the dominant frequency amplitude. The main frequency is independent of amplitude and soil depth. At the vibration distance of 250 mm, the dominant frequency is approximately twice the vibration frequency at 7–11 Hz and approximately equal to the vibration frequency at 13–15 Hz. Multiple exponential functions were used to fit the peak pressure attenuation function, obtaining an effective transmission distance range of 347.15 to 550.37 mm for the 5kPa cut-off pressure. For a soil depth of 300 mm, the vertical shear wave diffusion angle is greater than the horizontal shear wave diffusion angle. The study clarifies the vibration response of soil under low-frequency vibration, which helps to design vibration type soil-engaging components of tillage machinery and match vibration parameters for energy saving and resistance reduction in soil tillage.

Preprint ARTICLE | doi:10.20944/preprints202308.1943.v1

The Implied Views of Bond Traders on the Spot Equity Market

Yifan He, Yuan Hu, Svetlozar Rachev

Subject: Business, Economics And Management, Finance Keywords: BDT model; zero-coupon bond; implied daily return; implied natural upturn probability; implied daily volatility

Online: 29 August 2023 (08:23:29 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.1820.v1

Techno-economic Assessment of the Viability of Commercial Solar PV System in Port Harcourt, Rivers State, Nigeria

Muzan Williams Ijeoma, Hao Chen, Michael Carbajales-Dale, Rahimat Oyiza Yakubu

Subject: Engineering, Energy And Fuel Technology Keywords: PV design; solar energy; feasibility analysis; life cycle cost; levelized cost of electricity; net present value; simple payback time; internal rate of return; economic assessment; environmental assessment.

Online: 28 August 2023 (09:22:30 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.1811.v1

A Weighted kNN Based Spatial Framework of Flood Inundation Risk for Coastal Tourism – A Case Study in Zhejiang, China

Shuang Liu, Nengzhi Tan, Rui Liu

Subject: Environmental And Earth Sciences, Environmental Science Keywords: climate change; sensitivity analysis; evaluation accuracy; hazard; year return period; overall accuracy

Online: 28 August 2023 (03:43:01 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.1638.v1

Covariant Integral Quantization of the Semi-Discrete SO(3)-Hypercylinder

Jean-Pierre Gazeau, Romain Murenzi

Subject: Physical Sciences, Quantum Science And Technology Keywords: Covariant Weyl-Heisenberg integral quantization; semi-discrete hypercylinder; coherent states; Weyl-Gabor operator; quantum models on SO(3); Wigner function; phase space portrait

Online: 23 August 2023 (08:51:38 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.0852.v1

Application of DEM Coupled with CFD to Predict the Erosive Wear Behavior of Arctic Vessel Hulls Subjected to Ice Impacts

Sung-Je Lee, Jang Hyun Lee

Subject: Engineering, Marine Engineering Keywords: wear; ice friction; discrete element method (DEM); computational fluid dynamics (CFD); DEM-CFD coupling

Online: 11 August 2023 (02:34:43 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.0426.v1

Assessing the Influence of Fracture Networks on Gas-Based Enhanced Oil Recovery Methods

Riyaz Kharrat, Nouri Alalim, Holger Ott

Subject: Engineering, Energy And Fuel Technology Keywords: Gas injection; Water Alternating Gas; Foam Assisted Water Alternating Gas; Discrete Fracture Model; Fractured reservoirs

Online: 7 August 2023 (02:12:14 CEST)

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Numerous reservoirs that play a significant role in worldwide petroleum production and reserves contain fractures. Typically, the fractures must form a connected network for a reservoir to be classified as naturally fractured. Characterizing the reservoir with a focus on its fracture network is crucial for modeling and predicting production performance. To simplify the solution, dual continuum modeling techniques are commonly employed. However, to use continuum-scale approaches, properties such as average aperture, permeability, and matrix fracture interaction parameters must be assigned, making it necessary to improve fracture depiction and modeling methods. This study investigates a fractured reservoir with a low matrix permeability and a well-connected fracture network. The focus is on the impact of the hyrachical fracture network on the production performance of gas-based enhanced oil recovery methods. The Discrete Fracture Model (DFN) was utilized to create comprehensive two-dimensional models for three processes: Gas Injection (GI), Water Alternating Gas (WAG), and Foam Assisted Water Alternating Gas (FAWAG). Moreover, dimensionless numbers were employed to establish connections between properties across the entire fracture hierarchy, spanning from minor to major fractures and encompassing the fracture intensity. The results indicate that the FAWAG is more sensitive to fracture types and networks than the WAG and GI processes. Hence, the sensitivity of the individual EOR method to the fracture network requires a respective depth of description of the fracture network. However, other factors, such as reservoir fluids properties and fracture properties, might influence the recovery when the minor fracture networks are excluded. This study has determined that, among the enhanced oil recovery (EOR) techniques examined, the significance of the hyrachical depth of fracture networks diminishes as the ratio of major (primary fracture) aperture to the aperture of medium and minor fractures increases. Additionally, the impact of the assisted-gravity drainage method was greater with increased reservoir height; however, as the intensity ratio increased, the relative importance of medium and minor fracture networks decreased.

Preprint ARTICLE | doi:10.20944/preprints202308.0165.v1

An Improved Image Compression Algorithm Using 2D DWT and PCA with Canonical Huffman Encoding

RAJIV RANJAN, Prabhat Kumar

Subject: Computer Science And Mathematics, Computer Science Keywords: Canonical Huffman Coding (CHC); 2D Discrete Wavelet Transform (2D DWT); hard thresholding; Lossy Image Compression

Online: 2 August 2023 (07:35:21 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202308.0036.v1

The Impact of Soil Tillage and Crop Residue Incorporation Systems on Agrophysical Soil Properties

Vaida Steponavičienė, Aušra Rudinskienė, Giedrius Žiūraitis, Vaclovas Bogužas

Subject: Biology And Life Sciences, Agricultural Science And Agronomy Keywords: long-term experiment; shear strength; soil aggregate stability; straw return; cover crop

Online: 1 August 2023 (09:54:32 CEST)

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Preprint ESSAY | doi:10.20944/preprints202307.1330.v1

Research on E-commerce Platform’s Return Strategies Considering Consumer Abusing Return Policies

Huixin Liu, Feng Du

Subject: Business, Economics And Management, Business And Management Keywords: abuse of return policy; network effect; return policy; platform operation strategy

Online: 19 July 2023 (10:11:33 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202307.0395.v1

Dynamic Probabilistic Risk Assessment of Commercial-Off-The-Shelf Drones in Nuclear-Contaminated Search and Rescue Missions

Arjun Earthperson, Mihai A. Diaconeasa

Subject: Engineering, Safety, Risk, Reliability And Quality Keywords: Dynamic Probabilistic Risk Assessment; Discrete Dynamic Event Tree; Dual-Graph Error Propagation Model; Continuous-Time Markov Chain; Error Propagation; OpenPRA; OpenEPL

Online: 6 July 2023 (10:48:21 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202307.0176.v1

Evaluation of the Early Intervention Physiotherapist Framework for Injured Workers in Victoria, Australia: Data Analysis Follow-up

Hadi Akbarzadeh Khorshidi, Uwe Aickelin, Andrea De Silva

Subject: Public Health And Healthcare, Physical Therapy, Sports Therapy And Rehabilitation Keywords: Early Intervention; Return to Work; Physiotherapists; Workers’ Compensation; Evaluation

Online: 4 July 2023 (09:43:06 CEST)

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Purpose: This study evaluates the performance of the Early Intervention Physiotherapist Framework (EIPF) for injured workers. This study provides a proper follow-up period (3 years) to examine the impacts of the EIPF program on injury outcomes such as return to work (RTW) and time to RTW. This study also identifies the factors influencing the outcomes. Methods: The study was conducted on data collected from compensation claims of people who were injured at work in Victoria, Australia. Injured workers who commenced their compensation claims after the first of January 2010 and had their initial physiotherapy consultation after the first of August 2014 are included. To conduct the comparison, we divided the injured workers into two groups: physiotherapy services provided by EIPF-trained physiotherapists (EP) and regular physiotherapists (RP) over the three-year intervention period. We used three different statistical analysis methods to evaluate the performance of the EIPF program. We used descriptive statistics to compare two groups based on physiotherapy services and injury outcomes. We also completed survival analysis using Kaplan-Meier curves in terms of time to RTW. We developed univariate and multivariate regression models to investigate whether the difference in outcomes achieved after adjusting for significantly associated variables. Results: The results showed that physiotherapists in the EP group on average dealt with more claims (over twice as many) than those in the RP group. Time to RTW for the injured workers treated by the EP group was significantly lower than for those who were treated by the RP group, indicated by descriptive, survival and regression analyses. Earlier intervention by physiotherapists led to earlier RTW. Conclusion: This evaluation showed that the EIPF program achieved successful injury outcomes three years after implementation. Motivating physiotherapists to intervene earlier in the recovery process of injured workers by initial consultation helps to improve injury outcomes.

Preprint ARTICLE | doi:10.20944/preprints202306.2190.v1

The Role of Crisis Management in Sustainable Post-Disaster Recovery

Cheila DUARTE COLARDELLE

Subject: Social Sciences, Safety Research Keywords: Natural disaster; anticipation; crisis management strategy; return on experience

Online: 30 June 2023 (09:40:12 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202306.1975.v1

Multistage Quality Prediction Using Neural Networks in Discrete Manufacturing Systems

Ruidong Li, Xiancheng Wang, Zeng Wang

Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: manufacturing execution system; quality prediction; discrete manufacturing; Multivariate Long and short-term memory

Online: 28 June 2023 (09:28:24 CEST)

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Preprint REVIEW | doi:10.20944/preprints202306.0625.v1

A State of the Art: Numerical Methods to Simulate Desiccation Cracks in Clayey Soils

Hector Ulises Levatti

Subject: Engineering, Civil Engineering Keywords: desiccation cracks in clayey soils; finite element method; lattice Boltzmann method; discrete element method; cellular automaton method; phase field method

Online: 8 June 2023 (10:20:07 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202306.0607.v1

Material Evaluation and Dynamic Powder Deposition Modeling of PEEK/CF Composite for Powder-bed Fusion Process

Jiang Li, Fulun Peng, Hongguang Li, Zhibing Ru, Junjie Fu, Wen Zhu

Subject: Engineering, Other Keywords: Powder-bed fusion; Composite polymers; Discrete element method; Material characterization; Additive manufacturing

Online: 8 June 2023 (08:19:32 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202306.0289.v2

Item-Oriented Personalized LDP for Discrete Distribution Estimation

Xin Li, Hong Zhu, Zhiqiang Zhang, Meiyi Xie

Subject: Computer Science And Mathematics, Other Keywords: Discrete distribution estimation; Local differential privacy; Item-oriented personalization; Randomized response

Online: 8 June 2023 (03:16:47 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.2153.v1

Centralization and Sharing of Information to Improve Local Decision-Making in a Home Health Care Center

Guillaume Dessevre, Cléa Martinez, Liwen Zhang, Christophe Bortolaso, Franck Fontanili

Subject: Public Health And Healthcare, Health Policy And Services Keywords: home health care routing & scheduling problem; resilience; discrete event simulation; optimization

Online: 2 June 2023 (03:32:02 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.2130.v1

Emergency Animal Boarding: A Social Return on Investment

Gemma Catherine Ma, Jioji Ravulo, Ursula McGeown

Subject: Social Sciences, Other Keywords: Companion animal; dog; cat; human-animal bond; Social Return on Investment; animal shelter; animal welfare

Online: 30 May 2023 (11:34:44 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.2029.v1

Efficient Distortion Mitigation and Partition Reduction in Mapping Earth's Geospatial Data: Dual Orthogonal Equidistant Cylindrical Projection Approach

Aleksandar Miroslav Dimitrijević, Aleksandar Milosavljević, Dejan Rančić

Subject: Computer Science And Mathematics, Information Systems Keywords: discrete global grid system; equidistant cylindrical projection; yin-yang; distortion

Online: 30 May 2023 (03:56:22 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.1354.v1

A Dynamic Model of Profit Maximization for a Carsharing Services: Astana, Republic of Kazakhstan

Beibut Amirgaliyev, Oleksandr Kuchanskyi, Yurii Andrashko, Didar Yedilkhan

Subject: Computer Science And Mathematics, Applied Mathematics Keywords: carsharing; dynamic model; discrete optimization; tessellation; profit maximization

Online: 18 May 2023 (15:01:28 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.1330.v1

Optimal Control of Discrete Time-varying System with Multiple Delays and Multiplicative Noises

Qiyan Zhang, Chunyang Sheng, Xiao Lu, Haixia Wang

Subject: Computer Science And Mathematics, Applied Mathematics Keywords: LQG control; multiple delays; discrete time-varying system; multiplicative noises

Online: 18 May 2023 (10:32:41 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.0820.v1

A Sustainable Closed-Loop Supply Chains Inventory Model Considering Optimal Number of Remanufacturing Times

Adel A. Alamri

Subject: Business, Economics And Management, Business And Management Keywords: reverse logistics; number of remanufacturing times; first remanufacturing cycle; time-varying parameters; demand dependent return rate

Online: 11 May 2023 (08:21:22 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.0761.v1

Spacetime as a Complex Network and the Cosmological Constant Problem

Alexander Nesterov

Subject: Physical Sciences, Theoretical Physics Keywords: Emergent spacetime; Discrete spacetime; Cosmological constant; Nonassociative geometry; Euler characteristic; Complex networks

Online: 10 May 2023 (14:28:45 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202305.0380.v1

Factor Associated with Return Visits by Elders within 72 Hours of Discharge from the Emergency Department

Li-Hsiang Wang, Hui-Ling Lee, Chun-Chih Lin, Ai-Ju Lan, Pei-Ting Huang, Chin-Yen Han

Subject: Public Health And Healthcare, Primary Health Care Keywords: Return visit; elder; emergency department; triage risk screening tool; discharge planning

Online: 6 May 2023 (05:19:28 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202304.0816.v1

Characterization of Positive Invariance of Quadratic Convex Sets for Discrete Systems Using Optimization Approaches

Yuyao Lei, Hongli Yang, Ivan Ganchev Ivanov

Subject: Computer Science And Mathematics, Applied Mathematics Keywords: discrete-time dynamic systems; positive invariance; ellipsoid; Lorenz cone; optimization

Online: 24 April 2023 (04:10:49 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202304.0413.v1

Non-Integer Dimension of Seasonal Land Surface Temperature (LST)

Sepideh Azizi, Tahmineh Azizi

Subject: Computer Science And Mathematics, Geometry And Topology Keywords: Land Surface Temperature; Climate Change; Fractal Geometry; Discrete Wavelet Transform

Online: 17 April 2023 (07:01:24 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202302.0374.v2

Detection of Meteoritic Amino Acids in Extremely Small Sample Sizes: Implications for Sample Return Missions

Christian Potiszil, Masahiro Yamanaka, Tsutomu Ota, Ryoji Tanaka, Katsura Kobayashi, Eizo Nakamura

Subject: Biology And Life Sciences, Biology And Biotechnology Keywords: Carbonaceous chondrite; sample return; amino acid; ultrahigh performance liquid chromatography; Orbitrap-mass spectrometry; organic matter; astrobiology; origin of life

Online: 20 March 2023 (04:36:39 CET)

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Preprint ARTICLE | doi:10.20944/preprints202303.0226.v1

Non-Vacuum Solutions, Gravitational Collapse and Discrete Singularity Theorems in Wolfram Model Systems

Jonathan Gorard

Subject: Physical Sciences, Mathematical Physics Keywords: general relativity; singularity theorems; discrete spacetime

Online: 13 March 2023 (09:58:15 CET)

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The celebrated geodesic congruence equation of Raychaudhuri, together with the resulting singularity theorems of Penrose and Hawking that it enabled, yield a highly general set of conditions under which a spacetime (or, more generically, a pseudo-Riemannian manifold) is expected to become geodesically incomplete. However, the proofs of these theorems traditionally depend upon a collection of assumptions about the continuum spacetime (and, in the physical case, the stress-energy distribution defined over it), including its global structure, its energy conditions, the existence of trapped null surfaces and the various volume/intersection properties of geodesic congruences, that are inherently difficult to translate to the case of discrete spacetime formalisms, such as causal set theory or the Wolfram model. Some, such as the discrete analog of Raychaudhuri's equation for the volumes of geodesic congruences, are subtle to formulate due to intrinsic differences in the behavior of discrete vs. continuous geodesics; for others, such as the definition of a trapped null surface, no appropriate translation is known for the general discrete case due to a lack of a priori coordinate information. It is therefore a non-trivial question to ask whether (and to what extent) there exist equivalently general conditions under which one expects discrete spacetimes to become geodesically incomplete, and how these conditions might differ from those in the continuum. This article builds upon previous work, in which the conformal and covariant Z4 (CCZ4) formulation of the Cauchy problem for the Einstein field equations, with constraint-violation damping, was defined in terms of Wolfram model evolution over discrete (spatial) hypergraphs for the case of vacuum spacetimes, and proceeds to consider a minimal extension to the non-vacuum case by introducing a massive scalar field distribution, defined in either spherical or axial symmetry. Under appropriate assumptions, this scalar field distribution admits a physical interpretation as a collapsing (and, in the axially-symmetric case, uniformly rotating) dust, and we are able to show, through a combination of rigorous mathematical analysis and explicit numerical simulation, that the resulting discrete spacetimes converge asymptotically to either non-rotating Schwarzschild black hole solutions or maximally-rotating (extremal) Kerr black hole solutions, respectively. Although the assumptions used in obtaining these preliminary results are very strong, they nevertheless offer hope that a more general, perhaps ultimately ``Penrose-like'', singularity theorem may be provable in the discrete spacetime case too.

Preprint ARTICLE | doi:10.20944/preprints202303.0076.v1

Impact Assessment of Free-Roaming Dog Population Management by CNVR in Greater Bangkok

Elly Hiby, Tuntikorn Rungpatana, Alicja Izydorczyk, Craig Rooney, Mike Harfoot, Robert Christley

Subject: Medicine And Pharmacology, Veterinary Medicine Keywords: Dog; Canine; Catch, Neuter; Vaccinate and Return; CNVR; Dog population management; Rabies; Dog welfare; Impact assessment

Online: 3 March 2023 (14:12:03 CET)

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Preprint ARTICLE | doi:10.20944/preprints202302.0522.v1

Discrete Analogue of Fishburn’s Fractional-Order Stochastic Dominance

Hoover H. F. Yin, Xishi Wang, Hugo Wai Leung Mak, Chun Sang Au Yong, Ian Y. Y. Chan

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: fractional-order stochastic dominance; discrete stochastic dominance; discrete utility; fractional sum

Online: 28 February 2023 (14:22:40 CET)

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Preprint ARTICLE | doi:10.20944/preprints202302.0419.v1

Self-Employed Canadians’ Experiences with Cancer and Work: A Qualitative Study

Christine Maheu, Maureen Parkinson, Caitlin Wong, Fatima Yashmin, Caroline Longpré

Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: self-employed; cancer; work; return to work; cancer survivors

Online: 24 February 2023 (04:44:52 CET)

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Preprint ARTICLE | doi:10.20944/preprints202302.0222.v2

Gauss Quadrature for Integrals and Sums

Abdulaziz D. Alhaidari

Subject: Computer Science And Mathematics, Computational Mathematics Keywords: Gauss quadrature; integral approximation; continuous measure; discrete measure; mixed measure; orthogonal polynomials; recursion relation

Online: 17 February 2023 (15:11:43 CET)

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Preprint ARTICLE | doi:10.20944/preprints202302.0045.v1

Particle-level Simulation of Magnetorheological Fluids: A Fully-Resolved Solver

Célio Fernandes, Salah Faroughi

Subject: Engineering, Mechanical Engineering Keywords: Magnetorheological Fluids; Computational Fluid Dynamics; Discrete Element Method; Immersed Boundary Method; OpenFOAM; LIGGGHTS

Online: 2 February 2023 (11:34:36 CET)

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Magnetorheological fluids (MRFs) are smart materials consisting of micro-scale magnetizable particles suspended in a carrier fluid. The rheological properties of a MRF can be changed from a fluid-state to a solid-state upon the application of an external magnetic field. This study reports the development of a particle-level simulation code for magnetic solid spheres moving through an incompressible Newtonian carrier fluid. The numerical algorithm is implemented within an open-source finite-volume solver coupled with an immersed boundary method (FVM-IBM) to perform fully-resolved simulations. The particulate phase of the MRF is modeled using the discrete element method (DEM). The resultant force acting on the particles due to the external magnetic field (i.e., magnetostatic polarization force) is computed based on the Clausius-Mossotti relationship. The fixed and mutual dipole magnetic models are then used to account for the magnetic (MAG) interactions between particles. Several benchmark flows were simulated using the newly-developed FVM-IBM-DEM-MAG algorithm to assess the accuracy and robustness of the calculations. First, the sedimentation of two spheres in a rectangular duct containing a Newtonian fluid is computed without the presence of an external magnetic field, mimicking the so-called drafting-kissing-tumbling (DKT) phenomenon. The numerical results obtained for the DKT case study are verified against published data from the scientific literature. Second, we activate both the magnetostatic polarization and the dipole-dipole forces and resultant torques between the spheres for the DKT case study. Next, we study the robustness of the FVM-IBM-DEM-MAG solver by computing multi-particle chaining (i.e., particle assembly) in a two-dimensional (2D) domain for area volume fractions of 20% (260 particles) and 30% (390 particles) under vertical and horizontal magnetic fields. Finally, the fourth computational experiment describes the multi-particle chaining in a three-dimensional (3D) domain allowing to study fully-resolved MRF simulations of 580 magnetic particles under vertical and horizontal magnetic fields.

Preprint ARTICLE | doi:10.20944/preprints202211.0434.v1

The Self-Simulation Theory:A Computational Theory of Consciousness

Suvradeep Chakraborty, Ritu Lahkar

Subject: Social Sciences, Cognitive Science Keywords: Consciousness; Simulation; Discrete; Memory; Perception; Computation

Online: 23 November 2022 (07:00:10 CET)

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Preprint ARTICLE | doi:10.20944/preprints202210.0167.v1

Trivariate Joint Distribution Modelling of Compound Events Using the Nonparametric D-Vine Copula Developed Based on Bernstein and Beta Kernel Copula Density Framework

Shahid Latif, Slobodan P. Simonovic

Subject: Engineering, Civil Engineering Keywords: compound flooding; D-vine copula; trivariate joint analysis; Bernstein estimator; Beta kernel estimator; parametric copulas; kernel density estimation; return periods

Online: 12 October 2022 (09:04:04 CEST)

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Low-lying coastal communities are often threatened by compound flooding (CF), which can be determined through the joint occurrence of storm surges, rainfall and river discharge either successively or in close succession. The trivariate distribution can demonstrate the risk of the compound phenomenon more realistically rather than considering each contributing factor independently or in a pairwise dependency. Recently vine copula has been recognized as the highly flexible approach to constructing a higher dimensional joint density framework. In such construction, parametric class copula with parametric univariate marginal distributions is often involved. Such incorporation can lack flexibility due to parametric functions with prior distribution assumptions about their univariate marginal and/or copula joint density. This study introduces the vine copula approach in a nonparametric setting by introducing Bernstein and Beta kernel copula density in establishing trivariate flood dependence. The proposed model is applied to 46 years of flood characteristics collected on the west coast of Canada. The univariate flood marginal distribution is modelled using nonparametric kernel density estimation (KDE). The 2-D Bernstein estimator and Beta kernel copulas estimator are tested independently in capturing pairwise dependencies to establish D-vine structure in a stage-wise nesting approach in three alternative ways, each by permutating the location of the conditioning variable. The best-fitted vine structure is selected using goodness-of-fit (GOF) test statistics. The performance of the nonparametric vine approach is also compared with the vine constructed in the parametric and semiparametric fitting procedure. Investigation reveals that the D-vine constructed using Bernstein copula with normal KDE marginals nonparametrically performed well in capturing dependence of the compound events. Finally, the derived nonparametric model is used in the estimation of trivariate OR- and AND-joint return periods, further employed in estimating failure probability (FP) statistics. The trivariate return periods for the AND-joint case are higher than for the OR-joint case for the same flood combination. Also, the trivariate flood hazard results in a high-value FP than bivariate and univariate events. Ignoring the trivariate dependence could result in the underestimation of FP

Preprint ARTICLE | doi:10.20944/preprints202210.0115.v1

Characteristics of the Fracture Process Zone for Reservoir Rock with Various Heterogeneity

Hongran Chen, Jingrui Niu, Mengyang Zhai

Subject: Engineering, Energy And Fuel Technology Keywords: Mode I crack; fracture process zone; heterogeneity; discrete element method; reservoir fracability

Online: 10 October 2022 (07:16:19 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202208.0162.v1

Horizon of Cryptocurrency Before Vs During COVID-19

Ikaputera Waspada, Dwi Fitrizal Salim, Astrie Krisnawati

Subject: Business, Economics And Management, Finance Keywords: COVID-19, Cryptocurrency Return, Risk, Transaction Volume

Online: 8 August 2022 (13:48:44 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202208.0019.v1

Mode Choice of City Tourists: Discrete Choice Modeling Based on Survey Data from A Major German City

Jonas Harz, Carsten Sommer

Subject: Engineering, Civil Engineering Keywords: discrete choice modeling; mode choice; travel behavior; city tourism; sustainable tourism; revealed preference data

Online: 1 August 2022 (10:13:39 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202207.0322.v1

The (big) Role of Family Constellations in Return Migration and Transnationalism

Bresena Kopliku, Elvisa Drishti

Subject: Social Sciences, Geography, Planning And Development Keywords: Albania; family; migration; return; transnationalism

Online: 21 July 2022 (10:45:48 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202207.0286.v1

Impact of COVID-19 Vaccination on Healthcare Worker Infection Rate and Outcome during SARS-CoV-2 Omicron Variant Outbreak in Hong Kong

Sze Tsing Jonpaul Zee, Lam Fung Kwok, Carmen Ka Man Kee, Ling Hiu Fung, Luke Wing Pan Luk, Chris Tsun Leung Chan, Alex Chin Pang Leung, Bella Pik Wa YU, Jhan Raymond L Hung, Kit Ying SzeTo, Queenie Wai Leng Chan, Bone Siu Fai Tang, Ada Wai Chi Lin, Edmond Shiu Kwan Ma, Koon Hung Lee, Chor Chiu Lau, Raymond Wai Hung Yung

Subject: Biology And Life Sciences, Immunology And Microbiology Keywords: SARS-CoV-2; Omicron variant of concern; homologous boosting; heterologous boosting; Coro-naVac; BNT162b2; healthcare worker; return-to-work

Online: 19 July 2022 (10:15:39 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202206.0259.v1

Parametric Vine Copula Framework in the Trivariate Probability Analysis of Compound Flooding Events

Shahid Latif, Slobodan P. Simonovic

Subject: Engineering, Civil Engineering Keywords: compound flooding event; vine copula; trivariate joint analysis; joint return period; conditional return period; hydrologic risk

Online: 20 June 2022 (05:17:56 CEST)

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The interaction between oceanographic, meteorological, and hydrological factors can result in an extreme flooding scenario in the low-lying coastal area, called compound flooding (CF) events. For instance, rainfall and storm surge (or high river discharge) can be driven by the same meteorological, tropical or extra-tropical cyclones, resulting in a CF phenomenon. The trivariate distributional framework can significantly explain compound events' statistical behaviour reducing the associated high-impact flood risk. Resolving heterogenous dependency of the multidimensional CF events by incorporating traditional 3-D symmetric or fully nested Archimedean copula is quite complex. The main challenge is to preserve all lower-level dependencies. An approach based on decomposing the full multivariate density into simple local building blocks via conditional independence called vine or pair-copulas is a much more comprehensive way of approximating the trivariate flood dependence structure. In this study, a parametric vine copula of a drawable (D-vine) structure is introduced in the trivariate modelling of flooding events with 46 years of observations of the west Coast of Canada. This trivariate framework searches dependency by combining the joint impact of annual maximum 24-hr rainfall and the highest storm surge and river discharge observed within the time ±1 day of the highest rainfall event. The D-vine structures are constructed in three alternative ways by permutation of the conditioning variables. The most appropriate D-vine structure is selected using the fitness test statistics and estimating trivariate joint and conditional joint return periods. The investigation confirms that the D-vine copula can effectively define the compound phenomenon's dependency. The failure probability (FP) method is also adopted in assessing the trivariate hydrologic risk. It is observed that hydrologic events defined in the trivariate case produce higher FP than in the bivariate (or univariate) case. It is also concluded that hydrologic risk increases (i) with an increase in the service design life of the hydraulic facilities and (ii) with a decrease in return periods.

Preprint ARTICLE | doi:10.20944/preprints202206.0077.v1

The Origin of the Fundamental Constants

José Garrigues-Baixauli

Subject: Physical Sciences, Mathematical Physics Keywords: Fundamental Constants; Planck length; Discrete Space-Time

Online: 6 June 2022 (09:36:40 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202206.0006.v1

Coastal Flooding & Sea-Level Rise: Calculation of Flood Risk Using Tide-Gauge Measurements

Stephen Taylor

Subject: Environmental And Earth Sciences, Oceanography Keywords: Sea Level Rise; coastal flooding; JPM; Gumbel; exceedance; extreme value statistics; flood return period; sea-defences

Online: 1 June 2022 (05:58:45 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202205.0010.v1

Age Analysis of Status Updating System with Probabilistic Packet Preemption

Jixiang Zhang, Yinfei Xu

Subject: Engineering, Control And Systems Engineering Keywords: age of information; discrete time status updating system; probabilistic preemption; probability generation function; stationary distribution

Online: 4 May 2022 (13:15:56 CEST)

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The age of information (AoI) metric was proposed to measure the freshness of messages obtained at the terminal node of a status updating system. In this paper, the AoI of discrete time status updating system with probabilistic packet preemption is investigated by analyzing the steady state of a three-dimensional discrete stochastic process. Assuming the queue used in system is Ber/Geo/1/2*/η, which represents that the system size is 2 and the packet in buffer can be preempted by fresher packet with probability η. Instead of considering system’s AoI separately, we use a three-dimensional state vector (n,m,l) to simultaneously track the real time changes of the AoI, the age of packet in server, and the age of packet waiting in buffer. We give the explicit expression of system’s average AoI, and show that the average AoI of system without packet preemption is obtained by letting η=0. When η is set to 1, the mean of AoI of system having Ber/Geo/1/2* queue is obtained as well. Combining the results we have obtained and comparing them with corresponding average continuous AoIs, we propose a possible relationship between average discrete AoI with Ber/Geo/1/c queue and the average continuous AoI with M/M/1/c queue. For each of two extreme cases where η=0 and η=1, we also determine the stationary distribution of AoI using the probability generation function (PGF) method. The relations between average AoI and the packet preemption probability η, as well as AoI’s distribution curves in two extreme cases are illustrated by numerical simulations. Notice that the probabilistic packet preemption may occur, for example, in an energy harvest (EH) node of wireless sensor network, where the packet in buffer can be replaced only when the node collects enough energy. In particular, to exhibit the usefulness of our idea and methods and highlight the merits of considering discrete time systems, in this paper we give much more explanations showing that how the results about continuous AoI is derived by analyzing the corresponding discrete time system, and how the discrete age analysis is generalized to the system with multiple sources. In terms of packet service process, we also propose our idea to analyze system’s AoI when the service time distribution is relaxed to be arbitrary.

Preprint ARTICLE | doi:10.20944/preprints202203.0330.v2

Two Manifestations of Market Premium in the Capitalization of Carbon-Forest Estates

Petri P. Kärenlampi

Subject: Biology And Life Sciences, Forestry Keywords: capital return rate; expected value; carbon storage; carbon rent

Online: 26 April 2022 (09:45:34 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202203.0234.v1

Demographic Variables Impact on Individual Investment Return

Md. Fazlul Huq Khan, Fakrul Ahmed

Subject: Business, Economics And Management, Finance Keywords: Stock Market; Individual return; Bangladesh

Online: 16 March 2022 (14:26:08 CET)

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Preprint CONCEPT PAPER | doi:10.20944/preprints202203.0129.v2

A Generic Scalable DFT Calculation Method for Vectors and Matrices Using Matrix Multiplications

Abdullah Aman Khan

Subject: Computer Science And Mathematics, Computational Mathematics Keywords: Discrete Fourier Transform; Fourier Transform; Twiddle factor

Online: 11 March 2022 (11:03:46 CET)

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Preprint ARTICLE | doi:10.20944/preprints202112.0303.v1

D3 Dihedral Logistic Map of Fractional Order

Marius-F. Danca, Nikolay Kuznetsov

Subject: Computer Science And Mathematics, Computational Mathematics Keywords: Discrete fractional-order system; Caputo delta fractional difference; Hidden attractor; Dihedral symmetry D3

Online: 20 December 2021 (10:20:56 CET)

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Preprint ARTICLE | doi:10.20944/preprints202102.0260.v3

SimulaD: A Novel Feature Selection Heuristics for Discrete Data

Mohammad Reza Besharati, Mohammad Izadi

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: Feature Selection; Discrete Data; Heuristics; Running average

Online: 7 December 2021 (11:28:35 CET)

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Preprint ARTICLE | doi:10.20944/preprints202111.0569.v1

Qualitative Modelling for Bridging Expert-Knowledge and the Social-Ecological Dynamics of an East African Savanna

Maximilien Cosme, Christelle Hély, Franck Pommereau, Paolo Pasquariello, Christel Tiberi, Anna Treydte, Cédric Gaucherel

Subject: Environmental And Earth Sciences, Environmental Science Keywords: ecosystem dynamics; discrete-event model; qualitative modelling; boolean model; state-and-transition model

Online: 30 November 2021 (12:39:11 CET)

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Preprint ARTICLE | doi:10.20944/preprints202110.0204.v2

Discrete Double Hilbert Exponential Sums Along Polynomials

HoYoung Song

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: Discrete; Double Hilbert transform; Circle method; exponential sums; discrete double Hilbert transform; discrete double exponential sums; Newton diagram

Online: 17 November 2021 (11:06:10 CET)

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Preprint ARTICLE | doi:10.20944/preprints202111.0169.v1

An Interpolation-Based Polynomial Method of Estimating the Objective Function Value in Scheduling Problems of Minimizing the Maximum Lateness

Alexander Alekseevich Lazarev, Darya Vladimirovna Lemtyuzhnikova, Andrey Alexandrovich Tyunyatkin

Subject: Computer Science And Mathematics, Mathematics Keywords: discrete mathematics; scheduling; optimization; interpolation; approximation; objective function.

Online: 9 November 2021 (13:24:19 CET)

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Preprint ARTICLE | doi:10.20944/preprints202110.0414.v1

Robust Sliding Mode Control of a Magnetic Levitation System: Continuous-Time and Discrete-Time Approaches

Pratik Vernekar, Vitthal Bandal

Subject: Engineering, Other Keywords: Chattering reduction; discrete-time sliding mode control; magnetic levitation system; multirate output feedback; robust control; sliding mode control (SMC)

Online: 27 October 2021 (13:33:34 CEST)

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Preprint TECHNICAL NOTE | doi:10.20944/preprints202101.0504.v2

Addendum to “The VIT Transform Approach to Discrete-Time Signals and Linear Time-Varying Systems”

Edward Kamen

Subject: Engineering, Control And Systems Engineering Keywords: VIT transform, discrete-time signals, linear time-varying systems

Online: 19 October 2021 (10:15:05 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202110.0179.v1

Impact of Well Placement in the Fractured Geothermal Reservoirs Based on Available Discrete Fractured System

Saeed Mahmoodpour, Mrityunjay Singh, Kristian Bär, Ingo Sass

Subject: Engineering, Energy And Fuel Technology Keywords: Well placement; CO2-EGS; water-EGS; Discrete fracture networks; THM modeling

Online: 12 October 2021 (12:40:20 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0490.v1

On a Skew t–discrete Gamma Alternative to the Normal-Poisson Model for Clustered Count Outcomes

Chénangnon Frédéric Tovissodé, Romain Lucas Glèlè Kakaï

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: Discrete gamma distribution; correlated counts; sparse-grid quadrature; empirical Bayes estimators

Online: 25 August 2021 (11:49:27 CEST)

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Preprint REVIEW | doi:10.20944/preprints202108.0485.v1

Potential for Increased Rural Electrification Rate in Sub-Saharan Africa using SWER Power Distribution Networks

Michael E. Irechukwu, Aviti T. Mushi

Subject: Engineering, Electrical And Electronic Engineering Keywords: Single wire earth return (SWER); power distribution networks; rural electrification rate (RER)

Online: 25 August 2021 (10:49:21 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0121.v1

Time-Delay Synchronization and anti-Synchronization of Variable-Order Fractional Discrete-Time of Chen-Rossler Chaotics Systems Using Variable-Order Fractional-Discrete Time PID Control

Joel Perez P., J. Javier Perez D., Jose P. Perez, Atilano Martinez Huerta

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: Variable-order fractional-discrete time systems; Synchronization and Anti-Synchronization; Lyapunov-Krasovskii Stability; Fractional Order Caputo Derivative; Time-Delay Fractional-Discrete Systems; Fractional Order Discrete Time PID Control

Online: 4 August 2021 (20:16:06 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202108.0094.v1

Closing the Performance Gap between Siamese Networks for Dissimilarity Image Classification and Convolutional Neural Networks

Loris Nanni, Giovanni Minchio, Sheryl Brahnam, Davide Sarraggiotto, Alessandra Lumini

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: Siamese networks; Ensemble of classifiers; Loss function; Discrete cosine transform

Online: 3 August 2021 (15:49:22 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202107.0439.v2

Two Sets of Initial Conditions on Boreal Forest Carbon Storage Economics

Petri P. Kärenlampi

Subject: Biology And Life Sciences, Forestry Keywords: capital return rate deficiency; expected value; carbon storage; carbon rent; albedo effect

Online: 2 August 2021 (13:28:23 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202107.0575.v1

Detection and Attribution of Lake Victoria’s Water-Level Fluctuations in a Changing Climate

Obed M. Ogega, James Mbugua, Herbert O. Misiani, Maurice Nyadawa, Enrico Scoccimarro, Hussen S. Endris

Subject: Environmental And Earth Sciences, Atmospheric Science And Meteorology Keywords: Lake Victoria; Climate change; Return periods; Detection and Attribution; DAMIP; CMIP6

Online: 26 July 2021 (13:42:00 CEST)

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This study investigated the influence of land-use and precipitation change and variability on Lake Victoria’s water-level fluctuations. Extreme precipitation events, corresponding to extreme water-levels, over the lake and its catchment area were identified and their return periods estimated by fitting them into a generalized extreme value (GEV) distribution. Using general circulation models from the 6^th phase of the Coupled Model Intercomparison Project (CMIP6)’s Detection & Attribution Model Intercomparison Project (DAMIP), an assessment of the potential contribution of human-induced climate change on the observed precipitation patterns over the study area was done. The greatest precipitation anomalies for the period 1900-2020 were recorded in 1961’s October-December (OND) season and 2019’s June-August (JJA) and OND seasons, corresponding to the period when the highest water-levels were recorded in Lake Victoria. While land-use change in the study domain was observed, extended and unusually heavy June to December 2019 precipitation bore the greatest responsibility for the 2019/2020 high water-levels in Lake Victoria. The OND precipitation event of 2019 was a 1-in-52-year event compared to the 1961’s 1-in-693 years. Differences in return periods at various parts of the lake imply a high spatial climate variability within the lake itself. An analysis of the fraction of attributable risk (FAR) showed natural variability to have a greater influence on the JJA and OND precipitation patterns over Lake Victoria than human-induced climate change. However, variability over the land area of the study domain was mainly driven by human-induced climate change rather than natural variability, implying a unique climate system over Lake Victoria. Findings from the current study enhance the understanding of Lake Victoria’s water budget and motivate for further research to inform effective strategies on the planning and use of Lake Victoria’s water resources in a changing climate.

Preprint ARTICLE | doi:10.20944/preprints202107.0570.v1

Normal and Abnormal Human Face Detection Based on DCT and FFT Techniques - A Proposed Method

Samir Bandyopadhyay, Shawni Dutta, Vishal Goyal, Payal Bose

Subject: Computer Science And Mathematics, Applied Mathematics Keywords: Face Detection; Euclidean Distance; Fast Fourier Transformation; Discrete Cosine Transformation; Facial Parts Detection; Frequency domain; Spatial domain

Online: 26 July 2021 (11:47:11 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202107.0206.v1

Sensitivity of Ultrasonic Coda Wave Interferometry to Material Damage - Observations from a Virtual Concrete Lab

Claudia Finger, Leslie Saydak, Giao Vu, Jithender J. Timothy, Günther Meschke, Erik H. Saenger

Subject: Chemistry And Materials Science, Biomaterials Keywords: damage detection; concrete-like structures; coda waves; ultrasound; wave propagation; discrete element modeling; sensitivity study

Online: 8 July 2021 (15:26:10 CEST)

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Preprint BRIEF REPORT | doi:10.20944/preprints202107.0169.v1

A Discrete Event Simulation Model for Analyzing the Unloading of Goods at a Port

Dayana Pacheco Bolaño, Alexander Troncoso-Palacio

Subject: Engineering, Automotive Engineering Keywords: Discrete events simulation; Logistics port; Merchandise transports; Unloading of goods.

Online: 7 July 2021 (08:33:45 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202107.0066.v1

Mechanism of the Sleeper-Ballast Dynamic Impact in Void Zones

Mykola Sysyn, Michal Przybylowicz, Olga Nabochenko, Jianxing Liu

Subject: Engineering, Automotive Engineering Keywords: ballasted track; unsupported sleepers; sleeper-ballast dynamic impact; dynamic simulation; analytic solution; discrete element modelling

Online: 2 July 2021 (15:39:20 CEST)

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Unsupported sleepers or void zones in ballasted tracks are one of the most recent and frequent track failures. The void failures have the property of intensive development that, without timely maintenance measures, can cause the appearance of cost-expensive local instabilities like subgrade damages. The reason of the intensive void development lies in the mechanics of the sleeper and ballast bed interaction. The particularity of the interaction is a dynamic impact that occur due to void closure. Additionally, void zones cause inhomogeneous ballast pressure distribution between the void zone and fully supported neighbour zones. The present paper is devoted studying the mechanism of the sleeper-ballast dynamic impact in the void zone. The results of experimental in-situ measurements of rail deflections showed the significant impact accelerations in the zone even for light-weight slow vehicles. A simple 3-beam numerical model of track and rolling stock interaction has shown the similar to the experimental measurements dynamic interaction. Moreover, the model shows that the sleeper accelerations are more than 3 times higher than the corresponding wheel accelerations and the impact point appear before the wheel enters the impact point. The analysis of ballast loadings shows the specific impact behaviour in combination with the quasistatic part that is different for void and neighbour zones, which are characterised with high ballast pre-stressed conditions. The analysis of void sizes influence demonstrate that the impact loadings, wheel and sleeper maximal accelerations appear at certain void depth after which the values decrease. The ballast quasistatic loading analysis indicates more than twice increase of the ballast loading in neighbour zones for long voids and almost full quasistatic unloading for short length voids. However, the used imitation model cannot explain the nature of the dynamic impact. The mechanism of the void impact is clearly explained by the analytic solution using a simple clamped beam. A simplified analytical expression of the void impact velocity shows that it is linearly related to the wheel speed and loading. The comparison to the numerically simulated impact velocities shows a good agreement and the existence of the void depth with the maximal impact. An estimation of the long-term influences for the cases of normal sleeper loading, high ballast pre-stress and quasistatic loading in the neighbour zones and high impact inside the void are performed.

Preprint ARTICLE | doi:10.20944/preprints202106.0733.v1

Fluid-Structure Interaction in Coronary Stents: a Discrete Multiphysics Approach

Adamu Musa Mohammed, Mostapha Ariane, Alessio Alexiadis

Subject: Engineering, Automotive Engineering Keywords: Discrete multiphysics; smooth particle hydrodynamics; Lattice Spring Model; Fluid-structure interaction; particle-based method; Coronary stent; Atherosclerosis

Online: 30 June 2021 (11:55:59 CEST)

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Working Paper ARTICLE

Investigation of Lateral Confinement, Roller Aspect Ratio and Wear Condition on HPGR Performance using DEM-MBD-PRM Simulations

Victor Alfonso Rodriguez, Gabriel K.P. Barrios, Gilvandro Bueno, Luís Marcelo Tavares

Subject: Engineering, Automotive Engineering Keywords: Discrete element method, simulation, multibody dynamics, particle replacement, high-pressure grinding rolls.

Online: 23 June 2021 (13:36:08 CEST)

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Working Paper ARTICLE

Volatility Spillover between Developed and Developing Countries: The Global Foreign Exchange Market’s Channel

Walid Abass Mohammed

Subject: Business, Economics And Management, Accounting And Taxation Keywords: Foreign Exchange Market, Volatility Spillover, Return Spillover, VAR Framework, Variance Decomposition, Financial Crisis, Financial Interdependence

Online: 8 June 2021 (13:03:39 CEST)

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Preprint ARTICLE | doi:10.20944/preprints202106.0197.v1

The Symmetries of Quantum and Classical Information. The Ressurected “Ether" of Quantum Information

Vasil Penchev

Subject: Physical Sciences, Acoustics Keywords: confinement; discrete reference frame; still more general principle of relativity; quantum-information conservation; symmetries of information; the ether

Online: 8 June 2021 (08:55:31 CEST)

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The paper considers the symmetries of a bit of information corresponding to one, two or three qubits of quantum information and identifiable as the three basic symmetries of the Standard model, U(1), SU(2), and SU(3) accordingly. They refer to “empty qubits” (or the free variable of quantum information), i.e. those in which no point is chosen (recorded). The choice of a certain point violates those symmetries. It can be represented furthermore as the choice of a privileged reference frame (e.g. that of the Big Bang), which can be described exhaustively by means of 16 numbers (4 for position, 4 for velocity, and 8 for acceleration) independently of time, but in space-time continuum, and still one, 17th number is necessary for the mass of rest of the observer in it. The same 17 numbers describing exhaustively a privileged reference frame thus granted to be “zero”, respectively a certain violation of all the three symmetries of the Standard model or the “record” in a qubit in general, can be represented as 17 elementary wave functions (or classes of wave functions) after the bijection of natural and transfinite natural (ordinal) numbers in Hilbert arithmetic and further identified as those corresponding to the 17 elementary of particles of the Standard model. Two generalizations of the relevant concepts of general relativity are introduced: (1) “discrete reference frame” to the class of all arbitrarily accelerated reference frame constituting a smooth manifold; (2) a still more general principle of relativity to the general principle of relativity, and meaning the conservation of quantum information as to all discrete reference frames as to the smooth manifold of all reference frames of general relativity. Then, the bijective transition from an accelerated reference frame to the 17 elementary wave functions of the Standard model can be interpreted by the still more general principle of relativity as the equivalent redescription of a privileged reference frame: smooth into a discrete one. The conservation of quantum information related to the generalization of the concept of reference frame can be interpreted as restoring the concept of the ether, an absolutely immovable medium and reference frame in Newtonian mechanics, to which the relative motion can be interpreted as an absolute one, or logically: the relations, as properties. The new ether is to consist of qubits (or quantum information). One can track the conceptual pathway of the “ether” from Newtonian mechanics via special relativity, via general relativity, via quantum mechanics to the theory of quantum information (or “quantum mechanics and information”). The identification of entanglement and gravity can be considered also as a ‘byproduct” implied by the transition from the smooth “ether of special and general relativity’ to the “flat” ether of quantum mechanics and information. The qubit ether is out of the “temporal screen” in general and is depicted on it as both matter and energy, both dark and visible.

Preprint ARTICLE | doi:10.20944/preprints202106.0029.v1

Potential-Growth Indicators Revisited: More Merits of Indication

Dmitrii O. Logofet, Valerii N. Razzhevaikin

Subject: Computer Science And Mathematics, Discrete Mathematics And Combinatorics Keywords: discrete-structured population; matrix population model; population projection matrices; calibration; net reproductive rate; reproductive uncertainty; colony excavation; Diophantine systems

Online: 1 June 2021 (11:49:45 CEST)

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