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The Strategy and Countermeasure of E-Commerce Development for Chinese Retailing Enterprises
Chunhua Ju 한국통상정보학회 2004 통상정보연구 Vol.6 No.3
Chinese retailing enterprises have been facing a tough competition from foreign retail giants since China entered WTO. They must change their traditional ways of doing business and adopt new information technologies and electronic commerce in order to survive. This paper analyzes the current situation and the problems in Chinese retailing enterprises, including the cultural, the social, the technological and the environmental aspects. It gives strategies, tactics and countermeasures of E-Commerce development for Chinese retailing enterprises.
Power Source Sizing of Fuel Cell Hybrid Vehicles Considering Vehicle Performance and Cost
Chunhua Zheng,차석원,Guoqing Xu,정종렬,박영일,임원식 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.15 No.3
Power source sizing is an important step when designing hybrid vehicles, which directly influences the fuel economy and total cost of hybrid vehicles. This research presents a power source sizing methodology for fuel cell hybrid vehicles (FCHVs) considering the vehicle performance and cost. Acceleration time and maximum speed of the vehicle are introduced as the constraints on choosing effective power source size combinations. The powertrain mass difference resulted from different power source sizes is taken into account when dealing with the constraints, and consequently different constraint line is applied to different power source size combination. Different sizes of batteries and fuel cell systems (FCSs) in the effective region are modeled in order to select the best power source size combination according to sizing objectives (criterion). The sizing objective in this research is to minimize the fuel consumption or to minimize the total cost (FCS cost plus battery cost plus consumed hydrogen cost). A Pontryagin’s Minimum Principle (PMP)-based power management strategy is adopted when comparing the fuel consumption, and some reference values are introduced to the cost comparison. Power source sizing results reveal that the best power source size combination is different for the two sizing objectives.
A Hybrid Energy Storage System for an Electric Vehicle and Its Effectiveness Validation
Chunhua Zheng,Yafei Wang,Zhongxu Liu,Tianfu Sun,Namwook Kim,Jongryeol Jeong,차석원 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.6
A hybrid energy storage system (HESS), which consists of a battery and a supercapacitor, presents good performances on both the power density and the energy density when applying to electric vehicles. In this research, an HESS is designed targeting at a commercialized EV model and a driving condition-adaptive rule-based energy management strategy (EMS) is proposed for the HESS, which takes into account the superiority achievement of each ESS and also the protection to each ESS. The effectiveness of the HESS plus the EMS compared to the single battery case is validated by both the computer simulation and the semi-physical rapid control prototype (RCP) test bench. An electric loading equipment is adopted in the RCP experiment validation for simulating the vehicle driving cycle instead of the traditional combination of a motor and a dynamometer. Both validation results show that compared to the single battery case, the working status of the battery is stabilized by the addition of the supercapacitor in the HESS case during both the propelling and regeneration modes and the battery energy is also saved. A dynamic degradation model for the battery is adopted in order to evaluate the life cycle cost of the HESS. Results show that the HESS plus the EMS has the effect of prolonging the battery lifetime and the HESS is economically effective compared to the single battery case.
( Chunhua Ju ),( Qi Shao ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.10
This paper studies the distributed energy efficient resource management in the Internet of Things (IoT). Wireless communication networks support the IoT without limitation of distance and location, which significantly impels its development. We study the communication channel and energy management in the wireless communication network supported IoT to improve the ability of connection, communication, share and collaboration, by using the game theory and distributed learning algorithm. First, we formulate an energy efficient neighbor collaborative game model and prove that the proposed game is an exact potential game. Second, we design a distributed energy efficient channel selection learning algorithm to obtain the global optimum in a distributed manner. We prove that the proposed algorithm will asymptotically converge to the global optimum with geometric speed. Finally, we make the simulations to verify the theoretic analysis and the performance of proposed algorithm.
A Deep Reinforcement Learning-Based Energy Management Strategy for Fuel Cell Hybrid Buses
Chunhua Zheng,Wei Li,Wei-Min Liu,Kun Xu,Lei Peng,차석원 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.9 No.3
An energy management strategy (EMS) plays an important role for hybrid vehicles, as it is directly related to the power distribution between power sources and further the energy saving of the vehicles. Currently, rule-based EMSs and optimizationbased EMSs are faced with the challenge when considering the optimality and the real-time performance of the control at the same time. Along with the rapid development of the artificial intelligence, learning-based EMSs have gained more and more attention recently, which are able to overcome the above challenge. A deep reinforcement learning (DRL)-based EMS is proposed for fuel cell hybrid buses (FCHBs) in this research, in which the fuel cell durability is considered and evaluated based on a fuel cell degradation model. The action space of the DRL algorithm is limited according to the efficiency characteristic of the fuel cell in order to improve the fuel economy and the Prioritized Experience Replay (PER) is adopted for improving the convergence performance of the DRL algorithm. Simulation results of the proposed DRL-based EMS for an FCHB are compared to those of a dynamic programming (DP)-based EMS and a reinforcement learning (RL)-based EMS. Comparison results show that the fuel economy of the proposed DRL-based EMS is improved by an average of 3.63% compared to the RL-based EMS, while the difference to the DP-based EMS is within an average of 5.69%. In addition, the fuel cell degradation rate is decreased by an average of 63.49% using the proposed DRL-based EMS compared to the one without considering the fuel cell durability. Furthermore, the convergence rate of the proposed DRL-based EMS is improved by an average of 30.54% compared to the one without using the PER. Finally, the adaptability of the proposed DRL-based EMS is validated on a new driving cycle, whereas the training of the DRL algorithm is completed on the other three driving cycles.
Chunhua Ma,Xia Ye,Yanhui Chen,Jiancan Feng,Xiaoli Shang,Jidong Li,Yingxia Wu,Jianbin Hu 한국원예학회 2012 Horticulture, Environment, and Biotechnology Vol.53 No.4
The histological process of adventitious shoot regeneration from the leaf explants of Zizyphus jujuba ‘Huizao’was reported in this study. This is the first report on the detailed histological process of direct shoot regeneration from leaf explants in Z. jujube. Shoot regeneration was obtained from woody plant medium (WPM) supplemented with 2.27 μM thidiazuron (TDZ), 1.07 μM α-naphthalene-acetic acid (NAA) and 2.94 μM silver nitrate (AgNO3) for 10days in the dark followed by 3 weeks at a 14 hours photoperiod. The adventitious buds mostly formed from leaf veins and petioles, and the further histological studies revealed that there were multiple vascular bundles around leaf veins and the adaxial side of explants, and the adventitious buds directly originated from the parenchymatous cells around the vascular bundles without the intervening callus phase. After 3 days of culture, the parenchymatous cells started dividing and meristemoids formed thereafter. The meristematic cells continued division and subsequently gave rise to bud primordia. Well-developed shoot buds through direct organogenesis was achieved after 20 days of culture.
A Tutorial for Key Problems in the Design of Hybrid Hierarchical NoC Architectures with Wireless/RF
Chunhua Xiao,Zhangqin Huang,Da Li 한국산학기술학회 2013 SmartCR Vol.3 No.6
As processing nodes scale up, it is difficult for traditional electronic networks to supply on-chip communication efficiently due to unacceptable latency, plus power and area consumption. Alternative interconnects, such as radio frequency interconnect (RF-I) and optical interconnect, have been explored as interconnection backbones. Hybrid hierarchical architectures with both traditional interconnects and emerging interconnects have been widely adopted to get excellent trade-off between latency and power. The hybrid hierarchical architecture with a wireless/RF-I backbone is more cost-efficient and feasible due to advantages in complementary metal oxide semiconductor compatibility, compared with other alternative interconnects, and has become one of the mainstreams of chip multi-processor systems. However, how to efficiently utilize the wireless/RF-I backbone is a new challenge for designers. Based on analysis of existing typical hybrid hierarchal wireless/RF-I architectures (HHWAs), the key problems in the Design of HHWAs are proposed here, and related potential solutions are provided. In particular, strategies for resource management of wireless/RF-I are explored in detail, and different solutions are discussed. This work is expected to serve as a basis for future HHWA designs.
PMP-based Power Management Strategy for Two-State Variable FCHV Systems and its Optimality
Chunhua Zheng,차석원,Guoqing Xu,박영일,임원식 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.15 No.4
The battery temperature affects the total fuel consumption in a hybrid vehicle, as it influences the battery efficiency and furtherinfluences the powertrain efficiency. In this research, a Pontryagin’s Minimum Principle (PMP)-based optimal control problem fora fuel cell hybrid vehicle (FCHV) is formulated in which the battery temperature is designated as a second-state variable other thanthe battery state of charge (SOC). Moreover, optimality of the two-state variable PMP-based power management strategy is discussedbased on a conclusion derived from previous research. Simulation results of the PMP-based strategy are compared to those ofDynamic Programming (DP) approach. It is concluded from this research that the two-state variable PMP-based power managementstrategy guarantees global optimality under certain battery assumptions. Meanwhile, the proposed strategy saves much timecompared to DP approach.
Identity-based Deniable Authenticated Encryption for E-voting Systems
( Chunhua Jin ),( Guanhua Chen ),( Jianyang Zhao ),( Shangbing Gao ),( Changhui Yu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.6
Deniable authentication (DA) is a protocol in which a receiver can generate an authenticator that is probabilistically indistinguishable from a sender. DA can be applied in many scenarios that require user privacy protection. To enhance the security of DA, in this paper, we construct a new deniable authenticated encryption (DAE) scheme that realizes deniable authentication and confidentiality in a logical single step. Compared with existing approaches, our approach provides proof of security and is efficient in terms of performance analysis. Our scheme is in an identity-based environment; thus, it avoids the public key certificate-based public key infrastructure (PKI). Moreover, we provide an example that shows that our protocol is applicable for e-voting systems.