ARTICLE | doi:10.20944/preprints202011.0480.v1
Subject: Business, Economics And Management, Business And Management Keywords: Electronic Commerce Industry; Economic Impact; Computalble General Equilibrium Model; COVID-19
Online: 18 November 2020 (14:10:11 CET)
(1)Background: To perform a simulation-based analysis of 2019 COVID-19 outbreak and how would the electronic commerce indursty help China’s economy resilient. (2)Methods: As the epidemic continues, it is possible to use Computable General Equilibrium model to simulate the economic consequences and analyse the role of electronic commerce industy in COVID-19 outbreak. (3)Results: Estimates and models produced at the time of the outbreak suggested that COVID-19 could have a catastrophic effect on China’s economy. National statistics were examined for anomalies that corresponded to the timing of COVID-19 outbreak and, where possible, the size of any gain or loss found estimated. Our analysis suggests that the electronic commerce industry could help China’s economy to recover by stimulating consumption, improving technological level and expanding investment. (4)Conclusions: This exercise holds important lessons for estimating the electronic commerce’s role of similar events – such as pandemic influenza – and measures to recover the economy. We suggest that electronic commerce industry should be paid more attention in economic development, especially in epidemic time. The implications of our findings are discussed in the light of a prospective epidemic.
ARTICLE | doi:10.20944/preprints202207.0284.v1
Subject: Physical Sciences, Applied Physics Keywords: two-level transition; electron dynamics; spin dynamics; spin angular momentum perturbation
Online: 19 July 2022 (09:53:58 CEST)
State transition in the multiple-levels system has the great potential applications in the quantum technology. In this article we employ a deterministic approach in complex space to analyze the dynamics of the 1s-2p electron transition in the hydrogen atom. The electron’s spin motion is embodied in the framework of quantum Hamilton mechanics that allows us to examine the transition dynamics more precisely. The transition is driven by an oscillating electric field in the z-direction. The electron’s transition process can be visualized by monitoring its motion in the complex space. The quantum potential and the total energy proposed in this paper provide new indices to observe the dynamic changes of electrons in the transition process.
ARTICLE | doi:10.20944/preprints202012.0733.v1
Subject: Physical Sciences, Quantum Science And Technology Keywords: complex stochastic differential equation; complex Fokker-Planck equation; quantum trajectory; complex probability; optimal quantum guidance law.
Online: 29 December 2020 (15:32:13 CET)
Probability is an open question in the ontological interpretation of quantum mechanics. It has been discussed in some trajectory interpretations such as Bohmian mechanics and stochastic mechanics. New questions arise when the domain of probability extends to the complex space, including the generation of complex trajectories, the definition of the complex probability, the relation of the complex probability to the real quantum probability, and so on. The complex treatment proposed here applies the optimal quantum guidance law to derive the stochastic differential (SD) equation governing the particle’s random motions in the complex plane. The ensemble of the complex quantum random trajectories (CQRTs) solved from the complex SD equation is used to construct the probability distribution ρc(t,x,y) of the particle’s position over the complex plane z=x+iy. The correctness of the obtained complex probability is confirmed by the solution of the complex Fokker-Planck equation. The significant contribution of the complex probability is that it can be used to reconstruct both quantum probability and classical probability, and to clarify their relationship. Although quantum probability and classical probability are both defined on the real axis, they are obtained by projecting complex probability onto the real axis in different ways. This difference explains why the quantum probability cannot exactly converge to the classical probability when the quantum number is large.
ARTICLE | doi:10.20944/preprints201811.0415.v1
Subject: Engineering, Civil Engineering Keywords: subway traffic; sustainable development; analytic hierarchy process (AHP); evaluation index; index system
Online: 19 November 2018 (04:42:49 CET)
According to the characteristics of the sustainable development of subway traffic, the establishment process of an evaluation index system is determined, and the evaluation method and basis are defined. The evaluation index system is established from the aspects of subway traffic sustainability, economic sustainability and urban coordination sustainability. The comprehensive evaluation method of the analytic hierarchy process (AHP) model is used to calculate the weights of comprehensive evaluation indexes at each level. Finally, the sustainable development model of Shijiazhuang subway traffic is evaluated. The results show that the proposed evaluation system and model reflect the degree of sustainable development of subway traffic and can be used for reference in the evaluation of regional subway traffic sustainable development.
ARTICLE | doi:10.20944/preprints201809.0158.v1
Subject: Engineering, Energy And Fuel Technology Keywords: Oil shale; Permeability; Pyrolysis; High temperature and high pressure
Online: 10 September 2018 (09:14:56 CEST)
In-situ injection of steam for heating of the subsurface is an efficient method for the recovery of oil and gas from oil shale where permeability typically evolves with temperature. We reported measurements on Jimusar oil shales(Xinjiang, China) at different temperatures to 600℃ and under recreated in situ triaxial stresses to obtain permeability evolution with temperature and stress. Permeability of tight oil shales evolves with temperature to a threshold temperature and peak temperature. The threshold temperature was subjected to triaxial stresses. For Jimusar oil shale, the threshold temperature ranges from 200℃ to 250℃ at ground stress of buried depth of 500m and from 350℃ to 400℃ at buried depth of 1000m. The peak temperature was almost not subjected to triaxial stress and the range is from 450℃ to 500℃ for all Jimusar samples. Pyrolysis plays an important role in permeability evolution and fundamentally changes permeability tendency and magnitude. At high temperature permeability exhibits a little reduction due to stress effect but still remains a high level due to pyrolysis. The above results show that oil shale mass can change from tight porous media into highly permeable media and oil & gas can easily flow through oil shale stratum.
ARTICLE | doi:10.20944/preprints202308.0513.v1
Subject: Chemistry And Materials Science, Analytical Chemistry Keywords: chemical ionization source; segmented quadrupole; oxygenated volatile organic compounds; chemical ionization; photoionization
Online: 7 August 2023 (11:44:27 CEST)
Single photon ionization (SPI) based on vacuum ultraviolet (VUV) lamps has been extensively investigated and applied due to its clean mass spectra as a soft ionization method. However, the photon energy of 10.6 eV and photons flux of 106 photons/s of commercial VUV lamp limits its range of ionizable analytes as well as sensitivity. This work designs a chemical ionization focusing integrated (CIFI) ionization source time-of-flight mass spectrometry (TOFMS) based on VUV lamp for the detection of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs). The photoelectrons obtained from the VUV lamp through the photoelectric effect ionized the oxygen in the air to obtain the reagent ions O2+, and segmented quadrupole constituted the ion-molecule-reaction region (IMR) and radially focused the ions using a radio-frequency electric field, which improved the yield and transport efficiency of the sample ions and the sensitivity of mass spectrometry, resulting in 44-fold and 1154-fold increase in signal response to benzene and pentanal, respectively. To verify the reliability of the ionization source, the linear correspondence and repeatability of benzene and pentanal were investigated. Satisfactory dynamic linearity was obtained in the concentration range of 5-50 ppbv, and daytime RSD reached 3.91% and 6.26%, respectively. Finally, the CIFI ionization source TOFMS was applied to the determination of OVOCs, and the LOD of 12 types of OVOCs can reach the pptv level, indicating that the ionization source has the potential for accurate and sensitive online monitoring of atmospheric OVOCs.
ARTICLE | doi:10.20944/preprints202309.0122.v1
Subject: Medicine And Pharmacology, Medicine And Pharmacology Keywords: Hydroxamic acids; Antibacterial; Anti-biofilm; Mycobacterium tuberculosis
Online: 4 September 2023 (15:33:31 CEST)
Hydroxamic acid (HA) derivates displayed antibacterial and antifungal activities. HA with various numbers of carbon atoms (C2, C6, C8, C10, C12 and C17), complexed to different metal ions Fe(II/III), Ni(II), Cu(II) and Zn(II) were evaluated for their antimycobacterial activities and their anti-biofilm activities. Some derivates, among others HA12Fe2, inhibited the development of Mycobacterium tuberculosis, Mycobacterium bovis BCG and Mycobacterium marinum biofilms and could even attack pre-formed Pseudomonas aeruginosa biofilm. Proteomic profiles showed that the potential targets of HA10FeCl were mainly related to mycobacteria stress adaptation, involving cell wall lipid biosynthesis, drug resistance and tolerance, siderophore metabolism. This study provides new insights regarding the antimycobacterial activities of the HA and their complexes, especially about their potential antibiofilm activities.
ARTICLE | doi:10.20944/preprints201703.0106.v1
Subject: Engineering, Electrical And Electronic Engineering Keywords: parallel loop; line switching; complex network theory; GN algorithm; comprehensive evaluation model
Online: 15 March 2017 (18:00:36 CET)
With the development of higher voltage power grid, the high and low voltage parallel loops are emerging, which lead to energy losses, even threaten the security and stability of power system. The multi-infeed HVDC configurations widely appearing in AC/DC interconnected power system make this situation even worse. Aimed at energy saving and system security, a decision optimization method for power grid operating condition with high and low voltage parallel loops is proposed in this paper. Firstly, considering hub substation distribution and power grid structure, parallel loop opening schemes are generated with GN algorithm. Then, candidate opening schemes are preliminarily selected from all these generated schemes based on a filtering index. Finally, with the influence on power system security, stability and operation economy in consideration, an evaluation model for candidate opening schemes is founded based on analytic hierarchy process (AHP). And a fuzzy evaluation algorithm is used to find the optimal scheme. Simulation results of New England 39-bus system and an actual power system validate the effectiveness and superiority of this proposed method.