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6. Innovation of Marketing Supply Chain Management Model Based on SICAS Modeling

Author

Mao Rui, Liu Youwei, and Yang Yida

Subjects
sicas, collaborative optimization model, evolutionary algorithm, optimal solution ranking, supply chain management, 68q05, Mathematics, QA1-939
Abstract

The marketing service system is not perfect enough to highlight the competitive advantages of enterprises, and improving the marketing supply chain management mode is an inevitable trend under the change of the market economic environment. The marketing supply chain management model proposed in this paper is based on the SICAS model to respond quickly to market and customer demand. A collaborative optimization model of the supply chain based on virtual inventory management is constructed to ensure the normal operation of the whole supply chain by deploying flexible inventory in the hands of customers, and the constructed model is solved by using an evolutionary algorithm based on indexes and an optimal solution sorting method based on regret theory. The feasibility and scientificity of the proposed management model are verified by analyzing the effect of applying the management model to J and S e-commerce companies and analyzing consumer evaluation. The results show that from 2014 to 2022, the purchasing cost of J e-commerce enterprises decreased by 0.0307 as a proportion of operating income, the inventory turnover ratio increased by 0.0869, the marketing cost and logistics cost increased by 189 million yuan and 3,878 million yuan, respectively, and the supply chain cost was effectively managed. At the same time, the consumer evaluation score of the marketing supply chain management model based on SICAS model is 3.608±0.043 points; the user experience is good, to a certain extent, to enhance the competitive advantage of the enterprise.

Published
2024
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9. A Novel Center of Mass (CoM) Perception Approach for Lower-Limbs Stroke Rehabilitation

Author

Liu, Youwei, Liu, Biao, Zhou, Zikang, Cai, Siqi, Xie, Longhan, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Li, Haizhou, editor, Ge, Shuzhi Sam, editor, Wu, Yan, editor, Wykowska, Agnieszka, editor, He, Hongsheng, editor, Liu, Xiaorui, editor, Li, Dongyu, editor, and Perez-Osorio, Jairo, editor

Published
2021
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19. Experimental Investigation of Thermal Runaway Behavior and Hazards of a 1440 Ah LiFePO 4 Battery Pack.

Author

Chen, Hao, Yang, Kai, Liu, Youwei, Zhang, Mingjie, Liu, Hao, Liu, Jialiang, Qu, Zhanzhan, and Lai, Yilin

Subjects
HEAT release rates, THYROID hormone receptors, ENERGY storage, FIREFIGHTING, HEAT conduction, HAZARDS, LITHIUM-ion batteries
Abstract

The thermal runaway (TR) behavior and combustion hazards of lithium-ion battery (LIB) packs directly determine the implementation of firefighting and flame-retardants in energy storage systems. This work studied the TR propagation process and dangers of large-scale LIB packs by experimental methods. The LIB pack consisted of twenty-four 60 Ah (192 Wh) LIBs with LiFePO4 (LFP) as the cathode material. Flame performance, temperature, smoke production, heat release rate (HRR), and mass loss were analyzed during the experiment. The results indicated that TR propagation of the LIB pack developed from the outside to the inside and from the middle to both sides. The development process could be divided into five stages corresponding to the combustion HRR peaks. In the initial stages, the main factor causing LFP battery TR under heating conditions was the external heat source. With the propagation of TR, heat conduction between batteries became the main factor. Hazard analysis found that the HRRmax of the LIB pack was 314 KW, more than eight times that of a single 60 Ah battery under heating conditions. The LIB pack had higher normalized mass loss and normalized THR (6.94 g/Ah and 187 KJ/Ah, respectively) than a single LFP battery. This study provides a reference for developing strategies to address TR propagation or firefighting in energy storage systems. [ABSTRACT FROM AUTHOR]

Published
2023
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23. A Ku-band Conformal Half-Yagi Antenna for Microwave Communication

Author

Lirong Mei, Naibo Zhang, Li Yang, Lang Lei, Yang Jingsong, Liu Youwei, Shujie Chu, and Zhou Yuqi

Subjects
Physics, Beam diameter, Offset (computer science), business.industry, Bandwidth (signal processing), Astrophysics::Instrumentation and Methods for Astrophysics, Conformal map, Microwave transmission, Ku band, Optics, business, Monopole antenna, Computer Science::Information Theory, Ground plane
Abstract

A conformal half-Yagi antenna is proposed in this work which can realize the directional pattern along the axial cylinder metal carrier. The antenna is designed based on the monopole antenna and traditional Yagi antenna. The proposed antenna is composed of an active monopole, one reflector pole and three director poles which are designed on the ground plane according to the operation frequency range. The proposed antenna achieves a wide bandwidth of over 20% from 14 GHz to 18 GHz which broken through the bandwidth limit of the traditional Yagi antenna. The design and optimization for the antenna was conducted in this work, and the simulated results of the maximum gain is about 8.7 dBi in the direction 25 degree offset from axial. And the gain is about 5 dBi in the axial direction, the beam width is about 89 degree in the azimuth direction and about 32 degree in the elevation direction. The S 11 is less than −15 dB in the frequency range of 14 GHz to 18 GHz. The prototype of the antenna is fabricated by the NC milling process on a whole aluminum plate which can obtain the good mechanical strength performance. The measured results of the S 11 and the gain can agree with the simulated results. The dimension of the prototype antenna is about 50 mm × 30 mm × 10 mm, and the height of the prototype antenna protruding the surface of the conformal carrier is only about 5 mm. And the weight of the prototype antenna is about 14.8 g which is suitable for installing on the platform of conformal cylinder metal carrier which required the light weight for microwave communication.

Published
2019

36. A New Type of Slurry Concentrator

Author

Liu Youwei, Ning Wang, and Jingwen Wang

Subjects
Signal processing, Terminal (electronics), Interference (communication), Computer science, law, Acoustics, Shielded cable, Process (computing), Slurry, Concentrator, Mineral processing, Signal, law.invention
Abstract

Aiming at the inaccuracy and discontinuity of slurry concentration measurement in the process of mineral processing at present. A new type of Slurry Concentrator and a real time measuring method with high reaction speed and good performance are designed and developed. The measurement tube is suspended directly at the measuring end of the electronic weighing device. The change of slurry concentration directly leads to the change of the weight of the measuring tube, and the weight signal is transmitted synchronously to the signal processing terminal, which makes the measurement quick and sensitive. First, the measured data is properly processed by filtering algorithm, and the interference signal is shielded. Then the processed data is trained and processed as the input data of ELM. Simple structure, easy installation, simple operation, low cost, long maintenance period and high accuracy of measurement data.

Published
2019

37. Visual Detection of Stockbridge Damper Slip on Power Transmission Lines Based on Key Points

Author

冯勇 Feng Yong, 刘又维 Liu Youwei, 唐立军 Tang Lijun, 樊绍胜 Fan Shaosheng, and 李浩涛 Li Haotao

Subjects
Electric power transmission, Visual detection, Stockbridge damper, business.industry, Slip (materials science), Structural engineering, Electrical and Electronic Engineering, business, Atomic and Molecular Physics, and Optics, Geology
Published
2020

40. Experimental research on thermal runaway characterization and mechanism induced by the shell insulation failure for LiFePO4Lithium-ion battery

Author

Chen, Hao, Liu, Youwei, Qu, Zhanzhan, Yang, Kai, Zhang, Mingjie, Hui, Dong, Zhang, Qianjun, Du, Gaoxian, and Su, Jiaming

Abstract

Insulation failure of energy storage systems can cause overvoltage between electrode and shell of the lithium–ion batteries (LIBs), endangering battery safety. In this research, the electrical and thermal behaviors of LIBs under different application methods of electrode and shell over–voltage were analyzed, combined with the failure characteristics of LIBs. The structural and chemical changes at each electrode were revealed using microscopic and spectroscopy characterizations. Results showed that the LIBs faults include shell breakdown, self–ignition, anode and shell connection, and thermal runaway (TR) under anode–shell overvoltage and cathode–shell overvoltage. The internal insulation structure, the rolling shape, and the application methods of overvoltage influenced LIBs faults. The fault process was divided into five stages: charge polarization, ion conduction, electrolyte decomposition and resistance rise, conduction–fusing, and shell–electrode short circuit. The conduction–fusing stage determined whether the LIBs undergo TR. The duration of each stage of battery faults exhibited a negative correlation with the amplitude of the overvoltage. The amplitude of the overvoltage dictated the duration of the battery's transition from overvoltage to TR. The magnitude of the overcurrent determined the probability of the battery undergoing TR. According to SEM, EDS, and XRD results, shell–anode overvoltage and shell–cathode overvoltage led to the growth of iron dendrites on the anode, while anode–shell overvoltage and cathode–shell overvoltage led to the development of lithium dendrites on the shell, causing side reactions and releasing a large amount of heat, causing the TR of LIBs. The results provided a basis for the insulation designs for LIBs energy storage systems (BESS).

Published
2024
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43. Development and applications of line arresters in China

Author

Li Guofu, Du Shuchun, Chen Weijiang, and Liu Youwei

Subjects
Engineering, business.industry, Electronic engineering, business, Line (electrical engineering), Reliability engineering
Abstract

This paper summarized our surveys on the development and applications of metal oxide line arresters in China. The typical structures and main technical performances of those line arresters used in China are described. Computer analyses for specific key technical problems are carried out for those line arresters.

Published
2003

46. THE LEADER INCEPTION CHARACTERISTICS IN POSITIVE SPHERE-PLANE AIR GAPS

Author

Liu Youwei and Ma Naixiang

Subjects
Physics, business.industry, Electrical engineering, Rise rate, Atomic physics, Impulse (physics), business
Abstract

The leader inception characteristics in sphere-plane air gaps subjected to (250/ 2500 μs) positive impulse voltages are studied. The results show that the leader initiated by first corona is random, and the inception probability (Py) increases with the increment of radii of HV sphere electrodes and is influenced by the rise rate of impulse voltages. There is a transition region between PL=0 % and PL - 100 %.

Published
1987

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