ARTICLE | doi:10.20944/preprints202204.0176.v1
Subject: Computer Science And Mathematics, Algebra And Number Theory Keywords: ceiling function; floor function; Fibonacci Number; Generalised Dirichlet series; Lerch - Zeta Function; Hurwitz - Zeta function; Polylogarithm; Riemann-Zeta function
Online: 19 April 2022 (06:03:59 CEST)
In this part of the series of two papers, we extend the theorems discussed in part I for infinite series. We then use these theorems to develop distinct novel results involving the Hurwitz zeta function, Riemann zeta function, Polylogarithm and Fibonacci numbers. In continuation, we obtain some zeros of the newly developed zeta functions and explain their behaviour using plots in complex plane. Furthermore, we provide particular cases for the theorems and corollaries which show that our results generalise the currently available functions and series such as the Riemann zeta function and the geometric series. Finally, we provide four miscellaneous examples to showcase the vast scope of the developed theorems.
REVIEW | doi:10.20944/preprints202310.2024.v1
Subject: Public Health And Healthcare, Public Health And Health Services Keywords: BRIEF-P; floor effect; ceiling effect; executive functions; Attention-Deficit and Hyperactivity Disorders, ADHD, test, diagnostic validation
Online: 31 October 2023 (09:10:15 CET)
Background. ADHD is a neurodevelopmental disorder that is accompanied by executive deficits. Objectives. To obtain evidence of the usefulness of the BRIEF-P and to analyse the possible ceiling and floor effect of its scores in the assessment of executive function in preschoolers with signs compatible with a possible diagnosis of ADHD. Methods. Seven articles were selected from 2538 potentially eligible articles from different databases. We included studies assessing samples of individuals with symptoms compatible with ADHD, with age range 2-6 years, published in English or Spanish, during the period 2012-2022. References published in: Science Direct, NCBI (PubMed), ProQuest Education Journals in the last decade. Risk of bias was assessed using the QUADAS-2 questionnaire. The main variables were: age and executive functioning. Conclusions. Executive deficits in early-life individuals with ADHD-compatible symptoms are more extensive than deficits in working memory. BRIEF-P is an instrument that facilitates obtaining a sensitive and discriminative executive profile. It should be used in combination with other neuropsychological performance tests, finding a floor effect in tests associated with warm executive functions and a ceiling effect in cold executive functions. This requires using a variety of tests to assess executive performance in preschoolers with symptoms compatible with ADHD and designing intervention proposals in line with them...
REVIEW | doi:10.20944/preprints202108.0404.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: pelvic floor; bowel; dysfunction; sacral nerve; stimulation
Online: 19 August 2021 (12:19:52 CEST)
Prevention of obstetric trauma from damage to the pelvic floor is not always possible and sacral nerve stimulation (SNS) may be necessary later in life. Sacral nerve stimulation has been a promising innovation in the management of moderate to severe faecal incontinence and following sphincter repair failure. Although the indication spectrum for SNS is expanding, the success of neuromodulation for constipation is limited. Adverse events of SNS requiring re-intervention are not common but a long-term successful outcome may depend on interventions for maintenance of the device.
ARTICLE | doi:10.20944/preprints201702.0097.v1
Subject: Medicine And Pharmacology, Urology And Nephrology Keywords: LUTS; stress urinary incontinence; perimenopause; pelvic floor
Online: 27 February 2017 (17:41:42 CET)
Stress urinary incontinence (SUI) influences the quality of life of women. The research applied ICIQ LUTS qol (The International Consultation Incontinence Questionnaire Lower Urinary Tract Symptoms quality of life) as a tool to measure the quality of life (QOL) of patients with stage 1 SUI in many areas. 140 perimenopausal women who participated in a urodynamic test at Department of Gynecology, Endocrinology and Gynecologic Oncology, Pomeranian Medical University, Police, Poland in the years 2013-2015 were enrolled in the study. Patients were divided into two groups: A and B. Two questionnaires were applied: the author’s original questionnaire and the standardized ICIQ LUTS qol. Gymnastic plans were recommended 4 times per week for the period of 3 months. The plan for group A included the exercises of pelvic floor muscles (PFM) with the simultaneous tension of the transverse abdominal muscle (TrA) and for group B included the exercises of PMF without TrA. The evaluation of the quality of life of patients with stage 1 SUI with the use of ICIQ LUTS qol among patients from groups A and B after therapy showed a significant improvement in most areas. More impact is observed in the physiotherapy of both PFM with TrA.
ARTICLE | doi:10.20944/preprints201712.0168.v1
Subject: Chemistry And Materials Science, Materials Science And Technology Keywords: municipal waterworks sludge; waste; recycling; valorization; floor tiles
Online: 25 December 2017 (07:40:01 CET)
In municipal waterworks large amounts of waste in the form of sludge have to be discarded. This investigation focuses on the processing of ceramic floor tiles incorporated with a municipal waterworks sludge. Four floor tile formulations containing up to 10 wt. % of the municipal waterworks sludge in replacement of kaolin were prepared. The floor tile processing route consisted of dry powder granulation, uniaxial pressing, and firing between 1190 and 1250 °C using a fast-firing cycle (<60 min). The densification behavior and technological properties of the floor tile pieces as function of the sludge addition and firing temperature were determined. The development of the microstructure was followed by XRD and SEM/EDS. The results show that the replacement of kaolin with municipal waterworks sludge, in the range up to 10 wt. %, allows the production of ceramic floor tiles (group BIb and group BIIa, ISO 13006 Standard) at lower firing temperatures. These results suggest a new possibility for valorization of municipal waterworks sludge with many economical and environmental benefits.
ARTICLE | doi:10.20944/preprints201810.0755.v1
Subject: Computer Science And Mathematics, Information Systems Keywords: digital interventions; shop floor; evaluation framework; heuristics; smart factory
Online: 1 November 2018 (17:51:49 CET)
The introduction of innovative digital tools for supporting manufacturing processes has far-reaching effects on an organizational and an individual level due to the development of Industry 4.0. The FACTS4WORKERS project funded by H2020, i.e. Worker-Centric Workplaces in Smart Factories, aims to develop user-centered assistance systems in order to demonstrate their impact and applicability at the shop floor. To do so it is important to understand how to develop such tools and how to assess if advantages can be derived from the created ICT system. This study introduces the technology of a workplace solution that is linked to a specific industrial challenge. Subsequently, a 2-stepped approach to evaluate the presented system is discussed. Heuristics, which are an output of project “Heuristics for Industry 4.0”, are used to test if the developed solution covers critical aspects of socio-technical system design. Insights into the design, development and holistic evaluation of digital tools at the shop floor should be shown.
ARTICLE | doi:10.20944/preprints202203.0317.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: posterior edentulous maxilla; maxillary sinus; sinus floor elevation; tilted implants
Online: 23 March 2022 (12:49:55 CET)
The aim of this study was to evaluate implants survival rate, marginal bone loss, surgical and prosthetic complications of implants placed through sinus floor elevation and tilted implants en-gaged in basal bone in order to bypass maxillary sinus. 60 patients were enrolled for this study. According with residual bone height of posterior maxilla the sample was divided in three groups of 20 patients: Group A (lateral sinus floor elevation), Group B (transrectal sinus floor elevation) and Group C (tilted implants employed to bypass sinus floor). Follow-up visits were performed one week after surgery, at 3, 6 months and then once a year for next 4 years. The outcomes were implants survival rate, marginal bone loss and surgical and prosthetic complications. Although the Group A, B and C have demonstrated an implants survival rate of 83.3%, 86,7% and 98,3% respectively, the statistically analysis showed that there was no statistically significant difference between groups. Statistically significant differences between the groups were also not found con-cerning marginal bone loss, as recorded by intra-oral X-ray measurements during follow-up. About complications it wasn’t possible to perform a statistical analysis. To as to reduce potential surgical risks implants placement in basal bone should be preferred.
ARTICLE | doi:10.20944/preprints202101.0584.v1
Subject: Engineering, Civil Engineering Keywords: floor plan analysis; vectorization; graph neural network; indoor spatial data
Online: 28 January 2021 (13:06:28 CET)
This paper presents a new framework to classify floor plan elements and represent them in a vector format. Unlike existing approaches using image-based learning frameworks as the first step to segment the image pixels, we first convert the input floor plan image into vector data and utilize graph neural network. Our framework consists of three steps. (1) image pre-processing and vectorization of the floor plan image. (2) region adjacency graph conversion. (3) graph neural network on converted floor plan graphs. Our approach is able to capture different types of indoor elements including basic elements such as walls, doors, and symbols as well as spatial elements such as rooms and corridors. In addition, the proposed method can also detect element shapes. Experimental results show that our framework can classify indoor elements with an F1 score of 95%, with scale and rotation invariance. Furthermore, we propose a new graph neural network model that takes the distance between nodes into account, which is a valuable feature of spatial network data.
ARTICLE | doi:10.20944/preprints201901.0241.v1
Subject: Engineering, Civil Engineering Keywords: energy piles; validation; floor slab heat loss; energy; computer simulations
Online: 23 January 2019 (14:04:51 CET)
As the energy efficiency demands for future buildings become increasingly stringent, preliminary assessments of energy consumption are mandatory. These are possible only through numerical simulations, whose reliability crucially depends on boundary conditions. We therefore investigate their role in numerical estimates for the usage of geothermal energy, performing annual simulations of transient heat transfer for a building employing a geothermal heat pump plant and energy piles. Starting from actual measurements, we solve the heat equations in 2D and 3D using COMSOL Multiphysics and IDA-ICE, and discover a negligible impact of the multiregional ground surface boundary conditions. Moreover, we verify that the thermal mass of the soil medium induces a small vertical temperature gradient on the piles surface. We also find a roughly constant temperature on each horizontal cross-section, with nearly identical values if the average temperature is integrated over the full plane or evaluated at one single point. Calculating the yearly heating need for an entire building we then show that the chosen upper boundary condition affects the energy balance dramatically. Using directly the pipes’ outlet temperature induces a 54% overestimation of the heat flux, while the exact ground surface temperature above the piles reduces the error to 0.03%.
ARTICLE | doi:10.20944/preprints202307.1241.v1
Subject: Chemistry And Materials Science, Paper, Wood And Textiles Keywords: wood residuals; forest biomass; wood composite; wood floor; life cycle assessment
Online: 18 July 2023 (12:22:34 CEST)
Keywords: Wood residuals; Forest biomass; Wood composite; Wood floor; Life Cycle Assessment.
ARTICLE | doi:10.20944/preprints202105.0681.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: numerical homogenization; prefabricated floor slab; concrete; composite structure; strain energy equivalence
Online: 27 May 2021 (14:34:45 CEST)
The need for quick and easy deflection calculations of various prefabricated slabs causes that simplified procedures and numerical tools are used more and more often. Modelling of full 3D finite element (FE) geometry of such plates is not only uneconomical but often requires the use of complex software and advanced numerical knowledge. Therefore, numerical homogenization is an excellent tool, which can be easily employed to simplify a model, especially when accurate modelling is not necessary. Homogenization allows for simplifying a computational model and replacing a complicated composite structure with a homogeneous plate. Here, a numerical homogenization method based on strain energy equivalence is derived. Using the method proposed, the structure of the prefabricated concrete slabs reinforced with steel spatial trusses is homogenized to a single plate element with an effective stiffness. There is a complete equivalence between the full 3D FE model built with solid elements combined with truss structural elements and the simplified homogenized plate FE model. The method allows for the correct homogenization of any complex composite structures made of both solid and structural elements, without the need to perform advanced numerical analyses. The only requirement is a correctly formulated stiffness matrix of a representative volume element (RVE) and appropriate formulation of the transformation between kinematic constrains on RVE boundary and generalized strains.
ARTICLE | doi:10.20944/preprints201806.0127.v1
Subject: Engineering, Energy And Fuel Technology Keywords: Complicated structural region; Directional drilling; Grouting reinforcement; Coal floor; Karst aquifer
Online: 7 June 2018 (16:07:36 CEST)
Water inrush from coal floor constitutes one of the main disasters in mine construction and mine production, which always brings high risks and losses to the coal mine safe production. As the mining depth of coal fields in North China gradually increased, especially in the complicated structural region, the threat posed by limestone karstic water of coal floor to the safe stoping of mines has become increasingly prominent. In this paper, the Taoyuan coalmine was taken as an example, for which, the directional borehole grouting technology was utilized to reinforce the coal seam floor prior to mining. Also, the factors affecting the grouting effect were analyzed. These were the geological structure, the crustal stress and the range of slurry diffusion. The layout principle of grouting drilling was put forward and the directional drilling structure was designed. The water level observations in the end hole indicated that the target stratum was accurate and reliable. The effect of grouting was validated through the audio frequency electric perspective method and the holedrilling in the track trough. The results demonstrated that the effect of grouting in third limestone and the rock stratum above the third limestone of coal seam floor was apparent. Simultaneously, no water inrush occurred following the actual mining of the working face, which further demonstrated that the grouting reinforcement effect was apparent. The research findings were of high significance for the prevention and control of floor water disaster and water conservation in deep complex structural areas.
REVIEW | doi:10.20944/preprints202311.1545.v1
Subject: Medicine And Pharmacology, Obstetrics And Gynaecology Keywords: pelvic floor dysfunction; physical therapy; non-surgical treatment; intelligent diagnosis and treatment
Online: 24 November 2023 (02:37:08 CET)
Abstract: Female pelvic floor dysfunction (FPFD) is a series of conditions caused by the displacement or dysfunction of the patient's pelvic organs due to defects, injuries, and deterioration of the pelvic floor supportive structures, with stress urinary incontinence and pelvic organ prolapse being the most common. The mechanism of pelvic floor dysfunction is complex and not yet fully understood, and is often related to one or more functional abnormalities of muscles, connective tissues, fascia, nerves and blood vessels. Specialized clinicians are often unable to cover the comprehensive medical professional information of various specialties such as gynecology and obstetrics, urology, anus and intestines, imaging, etc., and the systematic and comprehensive diagnosis and treatment of the disease will be limited. The application of artificial intelligence concepts in the medical field not only improves the diagnostic efficiency of physicians, but also provides reference and basis for the development of comprehensive treatment programs. This article follows and draws on the diagnosis and treatment process of pelvic floor dysfunction recommended in various guidelines, incorporates physical therapy techniques into the conventional non-surgical treatment of pelvic floor dysfunction, provides guidance for the diagnosis and treatment of pelvic floor dysfunction, and briefly introduces the clinical application and value of pelvic floor intelligent diagnosis and treatment in pelvic floor dysfunction.
ARTICLE | doi:10.20944/preprints201804.0223.v4
Subject: Engineering, Marine Engineering Keywords: Gaofen-3; SAR; Wave Mode; calibration constants; cross-pol; noise floor; polarization
Online: 9 May 2018 (13:48:16 CEST)
In this paper, we analyze the measurements of the normalized radar cross-section(NRCS) in Wave Mode for Chinese C-band Gaofen-3(GF-3) synthetic aperture radar (SAR). Based on 2779 images from GF-3 quad-polarization SAR in Wave Mode and collocated wind vectors from ERA-Interim, we verify the feasibility of using ocean surface wind fields and VV-polarized NRCS to perform normalized calibration. The method uses well-validated empirical C-band geophysical model function (CMOD4) to estimate the calibration constant for each beam. The Amazon rainforest experiment results show that the accuracy of obtained calibration constant meets the requirements. In addition, the relationship between cross-pol NRCS and wind vectors is discussed. The cross-pol NRCS increases linearly with wind speed and it has an approximate cosine modulation with the wind direction when the wind speed is greater than 8m/s. The cross-polarized system noise floor is low enough to ignore it in wind retrieval. Furthermore, we also investigate the properties of the polarization ratio, denoted PR, and show that it is dependent on incidence angle and azimuth angle. Two empirical models of the PR are fitted, one as a function of incidence angle only, the other with additional dependence on azimuth angle. Assessments show that the σ_VV^0 retrieved from new PR models as well as σ_HH^0 is in good agreement with σ_VV^0 extracted from SAR images directly. And it is also shown that considering the azimuth angle can improve polarization conversion accuracy.
ARTICLE | doi:10.20944/preprints202311.1848.v1
Subject: Medicine And Pharmacology, Dentistry And Oral Surgery Keywords: orthodontic treatment; upper central; anterior nasal spine; nasal floor; CBCT; vertical growth pattern
Online: 29 November 2023 (06:31:31 CET)
The aim of this study was to examine the relationship of the distance between the apex tip of the upper central tooth (U1A) and the anterior nasal spine (ANS) and the nasal floor (NF) with the vertical cephalometric values using cone-beam computerized tomography (CBCT). A total of 122 patients who applied to Department of Orthodontics between January 2011-June 2019 were included. On the CBCT’s, distances between the U1A and the NF and ANS were measured. Statistical significance was considered as p<0.05. Of 122 individuals 73.8% (n=90) were female and 26.2% (n=32) were male with an mean age of 22,8±3,3 years. A statistically significant moderate positive correlation was found between the NF-U1A mean values and the measurements of N-Me, ANS-Me and ANS-Gn, S-Go, and N-ANS measurements (p <0.01). A statistically significant positive correlation was found between the ANS-U1A mean values and Ar-Go-Me, total posterior angles, N-Me, SN/GoGn and Y-axis angle, ANS-Me and ANS-Gn (p <0.01). In this study, we found that the distance of U1A from ANS and NF points was related to orthodontic vertical direction parameters. It was demonstrated that the ANS-U1A and NF-U1A points can serve as reference points for identifying the orthodontic vertical growth pattern on CBCT scans.
ARTICLE | doi:10.20944/preprints202309.0945.v1
Subject: Engineering, Energy And Fuel Technology Keywords: GCAM; Shell Conductance; Floor Area Ratio; AC Efficiency; GSHP; Rooftop PV; Carbon Emissions
Online: 14 September 2023 (05:10:34 CEST)
This paper reports modelling outcomes for improvements to building energy performance in Indonesia. Long-term climate effects due to building energy demands including carbon emissions are also considered. The global change assessment model (GCAM) was used to generate the related end-user building energy data, including socioeconomics for urban areas of Indonesia. As a comprehensive study, the total life cycle of carbon in the building sector and the concept of zero-carbon buildings, including energy efficiency, zero-emissions electricity and fuel switching options were considered. Building shell conductance (u-value) of building envelope, floor area ratio (FAR), air conditioner (AC) efficiency, electrical appliances (APLs) efficiency, rooftop photovoltaic (PV) performance and ground source heat pump (GSHP) systems were considered as parameters to mitigate carbon emissions under the operational energy category in GCAM. Carbon mitigation associated with the cement production process was considered in the raw material category. Urban population and labour productivity in Indonesia were used as base inputs with projected growth rates to 2050 determined from available literature. Low growth rate ‘LowRate’ and high growth rate ‘HighRate’ were considered as variable inputs for u-value, FAR, AC efficiency, APLs efficiency, and PV capacity factor to model emissions mitigation. The energy consumption of the GSHP was compared to the conventional reverse cycle ACs to identify the potential of the GSHP as a fuel-switching option. Only base input data were used for cement production process parameters without applying any variable inputs. GCAM base scenarios based on input data only (without modifying variable data) for the residential building sector in Indonesia were considered the benchmark for this study. Total potential carbon emissions mitigation was found to be 432 Mt CO2-e for the residential building sector in Indonesia over 2020-2050. It was found that an average of 24% carbon emissions mitigation could be achieved by 2020-30 and 76% in 2031-2050.
ARTICLE | doi:10.20944/preprints202209.0025.v1
Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: object detection; semi-supervised learning; Mask R-CNN; floor-plan images; computer vision
Online: 1 September 2022 (15:16:43 CEST)
Research has been growing on object detection using semi-supervised methods in past few years. We examine the intersection of these two areas for floor-plan objects to promote the research objective of detecting more accurate objects with less labelled data. The floor-plan objects include different furniture items with multiple types of the same class, and this high inter-class similarity impacts the performance of prior methods. In this paper, we present Mask R-CNN based semi-supervised approach that provides pixel-to-pixel alignment to generate individual annotation masks for each class to mine the inter-class similarity. The semi-supervised approach has a student-teacher network that pulls information from the teacher network and feeds it to the student network. The teacher network uses unlabeled data to form pseudo-boxes, and the student network uses both unlabeled data with the pseudo boxes and labelled data as ground truth for training. It learns representations of furniture items by combining labelled and unlabeled data. On the Mask R-CNN detector with ResNet-101 backbone network, the proposed approach achieves mAP of 98.8%, 99.7%, and 99.8% with only 1%, 5% and 10% labelled data, respectively. Our experiment affirms the efficiency of the proposed approach as it outperforms the fully supervised counterpart using only 10% of the labels.
ARTICLE | doi:10.20944/preprints201804.0207.v1
Subject: Engineering, Civil Engineering Keywords: deep mining; coal seam floor; unloading disturbance; space–time difference; stress shell; mechanical mechanism
Online: 16 April 2018 (11:29:05 CEST)
Failure characteristics induced by unloading disturbance and the corresponding mechanical mechanism of the coal seam floor are important theoretical bases for water-bursting prevention from the floor of the coal seam and rock burst alarm in deep mining. However, the existing two-dimensional ground-pressure-control theory based on shallow mining cannot sufficiently guide deep-mining practices. In this study, the redistribution of mining-induced stress field in rocks surrounding the longwall face and mechanical behaviors of strata in deep mining are investigated through a combination of numerical simulation, physical simulation, and field measurement. Results demonstrate that mining-induced stress fields in the floor of the longwall face differ in space and time. Vertical stress unloading from top to bottom of the floor and horizontal stress unloading are relatively low. A concentration zone of high horizontal stress exists at stope boundaries. The critical yield load of rock stratum in the floor is determined through thin plate yield theory. Under the combined effect of concentrated high horizontal and vertical resilience stresses, strata in the floor fracture from seam to seam if the load increases to the minimum critical buckling value. Fractured strata slide along the fracture surface, which leads to floor heave. The stope floor shows evident time-delay progressive failure characteristics. The stress shell in the stope floor in deep mining is found to be a sensitive mechanical parameter that produces three-dimensional ground-pressure behavior in the floor. This ground-pressure behavior in the stope floor is controlled by the existence of the corresponding stress shell and effects induced by its space–time evolution. This study provides theoretical basis for the dynamic control of a hazard-inducing environment in engineering and minimizing or altering disaster-occurrence conditions during the construction engineering of the coal seam floor.
ARTICLE | doi:10.20944/preprints201709.0099.v1
Subject: Biology And Life Sciences, Forestry Keywords: near-infrared spectroscopy; multivariate analysis; partial least-squares regression; floor litter; optimal wavelength selection
Online: 21 September 2017 (04:36:21 CEST)
Near-infrared spectroscopy (NIRS) was implemented to monitor the moisture content of broadleaf litters. Partial least-squares regression (PLSR) models, incorporating optimal wavelength selection techniques, have been proposed to better predict the litter moisture of forest floor. Three broadleaf litters were used to sample the reflection spectra corresponding the different degrees of litter moisture. Maximum normalization preprocessing technique was successfully applied to remove unwanted noise from the reflectance spectra of litters. Four variable selection methods were also employed to extract the optimal subset of measured spectra for establishing the best prediction model. The results showed that the PLSR model with the peak of beta coefficients method was the best predictor among all candidate models. The proposed NIRS procedure is thought to be a suitable technique for on-the-spot evaluation of litter moisture.
ARTICLE | doi:10.20944/preprints202311.1623.v1
Subject: Engineering, Safety, Risk, Reliability And Quality Keywords: Slip resistance; Dynamic friction coefficients (DCOF); Slip safety risk; Floor surfaces; Public service buildings (PSB)
Online: 29 November 2023 (09:20:44 CET)
The occurrence rate of occupational accidents caused by slipping and falling is 50% worldwide. Determining the slip safety risk is necessary to minimize the accidents caused by slipping in pedestrian walking areas. By on-site testing, this study aims to determine the slip risks of floor coverings used in walking areas with many pedestrians in public service buildings (PSB). For this purpose, on-site measurements were performed in two environments and six locations in PSB using portable GMG 200 and pendulum testers operating according to DIN 51131 and TS EN 14231 standards. These tests were performed on four-floor coverings with polished surface treatment in PSB. Since the floor coverings measured have a polished surface, it can be seen that the dynamic friction coefficients (DCOF) values are very low, and the slip risks are high. By statistically analyzing the slip test data using the K-means method, a new safety classification was made according to the usage areas of floor coverings. To minimize the risk of slip safety, especially for students, patients, and employees in PSB, it is recommended to use floor coverings with high DCOF values and low slip risk.
ARTICLE | doi:10.20944/preprints202304.0640.v1
Subject: Engineering, Architecture, Building And Construction Keywords: bamboo bundle veneer; bamboo bundle/wood veneer laminated composite; floor slabs; vibration performance; static deflection
Online: 20 April 2023 (09:43:19 CEST)
Bamboo engineering materials are green, high-strength, tough, durable, and structurally safe, and have promising application prospects in various modern green and low-carbon buildings. To invest the vibration behavior of new bamboo bundle veneer -laminated lumber (BLVL) for use in floor slabs, this study designed two kinds of full-scale vibration tests under a pedestrian load: an extraction hammer impact test, and a static concentrated load test, it is expected to provide theoretical and data support for the application of bamboo bundle veneer laminated composite materials in the construction field. The results showed that the self-oscillation frequency and mid-span deflection of the BLVL composite met the requirements of multiple relevant regulations when used as the structural material of floor slabs. The BLVL floor slab had a higher flexural stiffness and better vibration-damping performance than the OSB floor slab. The first-order self-oscillation frequency of the BLVL composite floor slab was 13.769 Hz, the damping ratio of the first three orders of modalities was 1.262–2.728%, and the maximum static deflection in the span of the joist was 0.932 mm under a 1 kN concentrated load. The 1 kN static deflection of the BLVL was reduced by 22.33%, and the root mean square (RMS) acceleration of the walking load response was significantly lower than that of the OSB floor slab. The preparation of BLVL composite materials by homogeneous lamination of bamboo bundle veneer and wood veneer may help improve the vibration behavior of bamboo-wood structures such as floor slabs and walls.
ARTICLE | doi:10.20944/preprints202306.2056.v1
Subject: Engineering, Civil Engineering Keywords: Floor types; interdisciplinary approach; Pompeii archaeological park; Villa of Diomedes; design formulations; barrel vaults; wooden floors
Online: 28 June 2023 (16:17:51 CEST)
The present work presents and discusses an analysis of the floor types of Villa of Diomedes (Pompeii archaeological park in the Campania region, Italy) both from architectural, archaeological, and structural point of view. In particular, the geometrical structural parameters of different floor types and the rules used by ancient builders to design them are investigated by means of interdisciplinary research. Link between structural-based assumptions, archival sources, geometric survey, in situ visual inspections and the archaeological information make it possible to define the geometrical structural parameters of eleven-barrel vaults, three wooden floors and three sloped wooden roofs (buried and collapsed during the Vesuvius eruption). A specific study of the barrel vaults is presented to investigate the relationships between the main vaults’ structural parameter. Furthermore, a comparison between the vaults’ dimensions obtained from surveys and those produced by the literature formulations from the 15th to the 20th centuries concerning masonry-vault designs is presented and discussed. These analyses carried out in the framework of Villa of Diomedes interdisciplinary project was very useful to interpret the fabrication of the Villa and to make a reconstruction of 3D model as it probably resulted to be the fateful year of 79 A.D.
ARTICLE | doi:10.20944/preprints201710.0141.v1
Subject: Engineering, Control And Systems Engineering Keywords: Vertical coal bunker; Coal given chamber; Floor heave; Wall-mounted coal bunker; Reinforcement; Self-bearing system
Online: 20 October 2017 (15:31:57 CEST)
Serious damage caused by floor heave in the coal given chamber of a vertical coal bunker is one of the challenges faced in underground coal mines. Engineering practice shows that it is more difficult to maintain the coal given chamber (CGC) than a roadway. More importantly, repairing the CGC during mining practice will pose major safety risks and reduce production. Based on the case of the serious collapse that occurred in the bearing structure of the CGC at the lower part of the 214# coal bunker in Xiashijie mine, China, this work analysed (i) the main factors influencing floor heave and (ii) the failure mechanism of the load-bearing structure in the CGC using FLAC2D numerical models and expansion experiment. The analysis results indicate that: the floor heave, caused mainly by mine water, is the basic reason leading to the instability and repeated failure of the CGC in the 214# coal bunker. Then a new coal bunker, without building the CGC, is proposed and put into practice to replace the 214# coal bunker. The FLAC3D software program is adopted to establish the numerical model of the wall-mounted coal bunker (WMCB), and the stability of the rock surrounding the WMCB is simulated and analysed. The results show that: (1) the rock surrounding the sandstone segment is basically stable. (2) The surrounding rock in the coal seam segment, which moves into the inside of the bunker, is the main zone of deformation for the entire rock mass surrounding the bunker. Then the surrounding rock is controlled effectively by means of high-strength bolt–cable combined supporting technology. According to the geological conditions of the WMCB, the self-bearing system, which includes (i) H-steel beams, (ii) H-steel brackets, and (iii) self-locking anchor cables, is established and serves as a substitute for the CGC to transfer the whole weight of the bunker to stable surrounding rock. The stability of the new coal bunker has been verified by field testing, and the coal mine has gained economic benefit to a value of 158.026174 million RMB over three years. The new WMCB thus made production more effective and can provide helpful references for construction of vertical bunkers under similar geological conditions.
ARTICLE | doi:10.20944/preprints202110.0089.v1
Subject: Computer Science And Mathematics, Artificial Intelligence And Machine Learning Keywords: Object Detection; Cascade Mask R-CNN; Floor Plan Images; Deep Learning; Transfer Learning; Dataset Augmentation; Computer Vision
Online: 5 October 2021 (15:09:26 CEST)
Object detection is one of the most critical tasks in the field of Computer vision. This task comprises identifying and localizing an object in the image. Architectural floor plans represent the layout of buildings and apartments. The floor plans consist of walls, windows, stairs, and other furniture objects. While recognizing floor plan objects is straightforward for humans, automatically processing floor plans and recognizing objects is a challenging problem. In this work, we investigate the performance of the recently introduced Cascade Mask R-CNN network to solve object detection in floor plan images. Furthermore, we experimentally establish that deformable convolution works better than conventional convolutions in the proposed framework. Identifying objects in floor plan images is also challenging due to the variety of floor plans and different objects. We faced a problem in training our network because of the lack of publicly available datasets. Currently, available public datasets do not have enough images to train deep neural networks efficiently. We introduce SFPI, a novel synthetic floor plan dataset consisting of 10000 images to address this issue. Our proposed method conveniently surpasses the previous state-of-the-art results on the SESYD dataset and sets impressive baseline results on the proposed SFPI dataset. The dataset can be downloaded from SFPI Dataset Link. We believe that the novel dataset enables the researcher to enhance the research in this domain further.
ARTICLE | doi:10.20944/preprints202311.1707.v1
Subject: Engineering, Civil Engineering Keywords: progressive collapse resistance; multi-column frame tube structure; truss beam composite floor; nonlinear dynamics; alternate load path method
Online: 27 November 2023 (13:16:14 CET)
To estimate the progressive collapse resistance capacity of a multi-column frame tube structure with the assembled truss beam composite floor (ATBCF), the pushdown analysis, and the nonlinear dynamic analysis as well, are conducted for such a structure by using the alternate load path (ALP) method. The bearing capacities of the remaining structures at three different work conditions, which are the side middle column failure, the edge middle column failure, and the corner column failure, are individually studied, and the collapse mechanism for the remaining structures is analyzed from the aspects of the internal force redistribution and the failure mode of the second defense line. Simultaneously, the influence of the column failure time on the dynamic response of the remaining structure and the dynamic amplification coefficient are discussed. The results show that the residual bearing capacity of the remaining structure with the bottom corner column failure is higher than that of the one with the side or edge middle column failure, while the latter has a stronger plastic deformation capacity. When the ALP method is adopted to operate the progressive collapse analysis, it is reasonable to take the column failure time as 0.1 times of the first-order vertical vibration period of the remaining structure, and it is suitable to set the dynamic amplification coefficient as of 2.0, which is the ratio of the maximum dynamic displacement to the static displacement of the remaining structure under the transient loading condition.
ARTICLE | doi:10.20944/preprints202305.0020.v1
Subject: Engineering, Transportation Science And Technology Keywords: auxiliary power supply system; low-floor light rail vehicle; dc train; parallel-connected dc-ac inverter; variable voltage variable frequency control
Online: 1 May 2023 (05:22:10 CEST)
This research proposes a roof-mounted auxiliary power supply (APS) system for 600VDC low-floor light rail vehicle (LRV). The proposed APS system consists of five parallel-connected dc-ac inverter modules (modules 1-5). The inverter modules 1 and 2 are three-phase dc-ac inverters for compressor motors of the cooling system, and the inverter modules 3 and 4 are three-phase dc-ac inverters for air pump motors of the braking system. The inverter module 5 is single-phase dc-ac inverter for 220VAC power supply for onboard electric loads. Simulations and experiments were carried out under variable load torque and output frequency for modules 1 – 4; and under full and no resistive loads for the inverter module 5. The measured total input current and total input power of the proposed APS system under full load condition are 118.76A and 71.25kW. Essentially, the proposed APS system is operationally applicable to the 600VDC low-floor RLV. Besides, the novelty of this research lies in the use of five parallel-connected inverter modules, unlike in the conventional APS systems which require three-phase output transformer or isolated dc-dc converter. Specifically, the proposed APS system requires neither three-phase output transformer nor isolated dc-dc converter.
ARTICLE | doi:10.20944/preprints201706.0106.v1
Subject: Chemistry And Materials Science, Biomaterials Keywords: Tricalcium phosphate putty scaffold; bioactive ceramics; bone formation, osteogenesis, osteogenic markers, hard tissue histology; immunohistochemical analysis; split-mouth design; sinus floor augmentation; bone grafting materials
Online: 22 June 2017 (18:33:01 CEST)
This study examines the effect of a hyaluronic acid (HyAc) containing tricalcium phosphate putty scaffold material (TCP-P) and of a particulate tricalcium phosphate (TCP-G) graft on bone formation, volume stability and osteogenic marker expression in biopsies sampled 6 months after bilateral sinus floor augmentation (SFA) in 7 patients applying a split-mouth design. Biopsies were processed for immunohistochemical analysis of resin embedded sections. Sections were stained for collagen type I (Col I), alkaline phosphatase (ALP), osteocalcin (OC) and bone sialoprotein (BSP). Furthermore, the bone area and particle area fraction were determined histomorphometrically. Cone-beam CT data recorded after SFA and 6 month later were used for calculating the graft volume at these two time points. TCP-P displayed more advantageous surgical handling properties and a significantly greater bone area fraction and smaller particle area fraction. This was accompanied by significantly greater expression of Col I and BSP and in osteoblasts and osteoid and a less pronounced reduction in grafting volume with TCP-P. SFA using both types of materials resulted in formation of sufficient bone volume for facilitating stable dental implant placement with all dental implants having been in function without any complications for 6 years. Since TCP-P displayed superior surgical handling properties and greater bone formation than TCP-G, without the Hyac hydrogel matrix having any adverse effect on bone formation or graft volume stability, TCP-P can be regarded as excellent grafting material for SFA in a clinical setting.