• Title/Summary/Keyword: Power Distribution Systems

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An Exploratory Study on the Distribution and Marketing Changes Under the North Korean System

  • LEE, Won-Jun
    • The Journal of Industrial Distribution & Business
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    • v.11 no.5
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    • pp.27-34
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    • 2020
  • Purpose: North Korea is a very close country geographically and culturally, but the nation has been one of the most secretive countries in the world. However, in recent years, North Korean society has been known to rapidly change its economic environment as well as its diplomatic and political environment. Since the gaining power of Jong-un, Kim in 2012, the North Korean government has implemented a new set of economic policies. North Korea has embraced limited market systems and mechanisms that have become a part of the formal planned economy. This study is concerned with the recent changes in the market and marketing activities of the communist country. It also seeks to gain an understanding of the changing market behavior of North Korean consumers. The purpose of this study is to enhance understanding of the market environments of North Korea and to provide appropriate implications for practitioners and researchers. Research design, data and methodology: Academic access to information that can understand North Korea's reality is minimal. Therefore, this study was conducted based on a qualitative analysis of secondary data. The existing literature on North Korea, related news and reports were the basis of the analysis. Analysis of secondary data related to North Korea was the main methodology of the study. Results: The official ideology of North Korea rejected most aspects of marketing, and yet there were marketing activities in North Korea. This article focuses on the development of market and marketing activities in North Korea during the recent years. This study indirectly confirmed that the market function is being activated in North Korea, and the basic functions of marketing such as advertisement, price, and distribution are being formed. In this process, the activation of the 'Jangmadang(market)' played a significant role. Conclusions: Research shows that North Korea is rapidly developing its own market function. In addition, marketing activities such as advertising and pricing strategies seem to be unprecedentedly active. However, due to changes in the political environment, the future development of North Korea's marketing is still in flux. Efforts to improve mutual understanding through continuous research are required.

Development of Low Latency Secure Communication Device for Legacy SCADA (저지연 Legacy SCADA 보안 통신장치 개발)

  • Choi, Moon-Suk;Kim, Chung-Hyo;Lim, You-Seok;Ju, Seong-Ho;Lim, Yong-Hun;Jeon, Kyung-Seok
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.2
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    • pp.339-346
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    • 2013
  • As the need for security of SCADA systems is increasing, significant progress has been made in research on security of control protocol. However, very few security solutions were adapted to legacy SCADA system. The reasons for non-adoption are latency, cost and key management problem. We propose a low latency, economic security Solution to solve these issues. The proposed solution performs security function in data link layer and has minimum overhead to minimize latency. Furthermore, we try to solve the key management problem by providing systematic security keys and key distribution method.

Development and Application of Wireless Power Transmission Systems for Wireless ECG Sensors (지속적인 심장질환 모니터링을 위한 인체 삽입형 생체 센서의 무선전력전송 시스템)

  • Heo, Jin-Chul;Lee, Jong-Ha
    • Journal of the Institute of Convergence Signal Processing
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    • v.20 no.2
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    • pp.111-117
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    • 2019
  • We investigated the variations in the magnetic-field distribution and power transmission efficiency, resulting from changes in the relative positions of the transmitting and receiving coils, for electromagnetic-induction-type wireless power transmission using an elliptical receive coil. Results of simulations using a high-frequency structure simulator were compared to actual measurement results. The simulations showed that the transmission efficiency could be maintained relatively stable even if the alignment between the transmitting and receiving coils was changed to some extent. When the centre of the receiving coil was perfectly aligned with the centre of the transmitting coil, the transmission efficiency was the maximum; however, the degree of decrease in the transmission efficiency was small even if the centre of the receiving coil moved by ± 10mm from the centre of the transmitting coil. Therefore, it is expected that the performance of the wireless power transmission system will not be degraded significantly even if perfect alignment is not maintained. The results suggested a standardized application method of wireless transmission in the utilization of wireless power for implantable sensors.

An Offloading Scheduling Strategy with Minimized Power Overhead for Internet of Vehicles Based on Mobile Edge Computing

  • He, Bo;Li, Tianzhang
    • Journal of Information Processing Systems
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    • v.17 no.3
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    • pp.489-504
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    • 2021
  • By distributing computing tasks among devices at the edge of networks, edge computing uses virtualization, distributed computing and parallel computing technologies to enable users dynamically obtain computing power, storage space and other services as needed. Applying edge computing architectures to Internet of Vehicles can effectively alleviate the contradiction among the large amount of computing, low delayed vehicle applications, and the limited and uneven resource distribution of vehicles. In this paper, a predictive offloading strategy based on the MEC load state is proposed, which not only considers reducing the delay of calculation results by the RSU multi-hop backhaul, but also reduces the queuing time of tasks at MEC servers. Firstly, the delay factor and the energy consumption factor are introduced according to the characteristics of tasks, and the cost of local execution and offloading to MEC servers for execution are defined. Then, from the perspective of vehicles, the delay preference factor and the energy consumption preference factor are introduced to define the cost of executing a computing task for another computing task. Furthermore, a mathematical optimization model for minimizing the power overhead is constructed with the constraints of time delay and power consumption. Additionally, the simulated annealing algorithm is utilized to solve the optimization model. The simulation results show that this strategy can effectively reduce the system power consumption by shortening the task execution delay. Finally, we can choose whether to offload computing tasks to MEC server for execution according to the size of two costs. This strategy not only meets the requirements of time delay and energy consumption, but also ensures the lowest cost.

A Study of Power Perception between Supplier and Retail Buyer of Agricultural Products (농산물공급자와 대형소매업체 바이어간의 상호 파워 인식에 대한 연구)

  • 서성무;이은정
    • Proceedings of the Korean DIstribution Association Conference
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    • 2003.02a
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    • pp.123-166
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    • 2003
  • Marketing channel is recognized as one of the society systems which have the character of functional organization. These organizations are related to each other for specialized and cooperative work. Channel members in distribution channel are striving to accomplish exchange through reciprocal action. Thus channel members exercise their power to take better position in exchange. There will be struggling between members about satisfaction and conflict during this power exercise. Now a days, buyers use more harsh power as large retail firms are increasing. This phenomenon is occurring in the distribution channel. However, there will be different phenomenon in case of agricultural products. Not like industrial product suppliers, agricultural product suppliers have various supply channels and many agricultural products are seasonal. It has also unstable amount supplies. There should be differentiated marketing in agricultural products. Relatively weaker powered suppliers have to strengthen comparative factors and also have to be technically specialized through assessed experience in order to establish strong product sales chain. Making a brand of agricultural product would be also a good idea to increase the product comparability. Channel members need to be recognized their specialized functions in order to make balanced distribution channel. There have to be conversion of concept of relation between suppliers and buyers from subordinate relationship to cooperative relationship.

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A Study on the Customer Voltage Characteristic Based on the Test Devices for PV Systems (태양광전원 계통연계 시험장치에 의한 수용가전압 특성에 관한 연구)

  • Park, Hyeon-Seok;Son, Joon-Ho;Ji, Seong-Ho;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.11
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    • pp.4529-4536
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    • 2010
  • This paper develops an interconnection test devices for photovoltaic(PV) systems composed of distribution system simulator, PV systems simulator and control and monitoring systems using the LabVIEW S/W, and simulates the customer voltage characteristics considering the 3 parameters on the introduction capacity for PV systems, system configuration and load factor. This paper also proposes a new calculation algorithm for voltage profile to make a comparison between calculation values and test device values. The results show that the test results for the normal operation characteristics of PV systems is very practical and effective.

Generalized load cycles for dynamic wind uplift evaluation of rigid membrane roofing systems

  • Baskaran, A.;Murty, B.;Tanaka, H.
    • Wind and Structures
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    • v.14 no.5
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    • pp.383-411
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    • 2011
  • Roof is an integral part of building envelope. It protects occupants from environmental forces such as wind, rain, snow and others. Among those environmental forces, wind is a major factor that can cause structural roof damages. Roof due to wind actions can exhibit either flexible or rigid system responses. At present, a dynamic test procedure available is CSA A123.21-04 for the wind uplift resistance evaluation of flexible membrane-roofing systems and there is no dynamic test procedure available in North America for wind uplift resistance evaluation of rigid membrane-roofing system. In order to incorporate rigid membrane-roofing systems into the CSA A123.21-04 testing procedure, this paper presents the development of a load cycle. For this process, the present study compared the wind performance of rigid systems with the flexible systems. Analysis of the pressure time histories data using probability distribution function and power spectral density verified that these two roofs types exhibit different system responses under wind forces. Rain flow counting method was applied on the wind tunnel time histories data. Calculated wind load cycles were compared with the existing load cycle of CSA A123.21-04. With the input from the roof manufacturers and roofing associations, the developed load cycles had been generalized and extended to evaluate the ultimate wind uplift resistance capacity of rigid roofs. This new knowledge is integrated into the new edition of CSA A123.21-10 so that the standard can be used to evaluate wind uplift resistance capacity of membrane roofing systems.

A Study on the PAPR Reduction and In-Band Distortion Compensation Schemes for Next Generation Mobile Communication Systems (차세대 이동통신 시스템을 위한 PAPR 감소와 대역 내 왜곡보정 기법에 대한 연구)

  • Roh, Jae-Sung;Kim, Wan-Tae
    • Journal of Advanced Navigation Technology
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    • v.16 no.2
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    • pp.234-239
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    • 2012
  • Next generation mobile communication systems have been studied and applied to support various services. In next generation mobile communication systems, the most interested research is the integration of various communication systems and the offer of various services by using high-speed data transmission. The integration of communication systems has been researched by using multi standard modem, while the high-speed data transmission for the offer of various services has been applied by using OFDM. This paper has proposed the method to reduce PAPR by using multi standard modem. with EVM, this paper has also suggested the method to compensate in-band distortion while reducing PAPR. By using the proposed methods, this paper has analyzed and simulated the decrease efficiency of PAPR, the performance of CCDF, and the performance of BER in next generation mobile communication systems. The simulation results improved the performance of next generation mobile communication system can be seen that.

Design of a Dynamically Reconfigurable Switch for Hybrid Network-on-Chip Systems (Hybrid Noc 시스템을 위한 재구성 가능한 스위치 설계)

  • Lee, Dong-Yeol;Hwang, Sun-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8B
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    • pp.812-821
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    • 2009
  • This paper proposes a novel dynamically reconfigurable switch for various multimedia applications in hybrid NoC systems. Current NoC systems, which adopt hybrid NoC structure with fixed switch and job distribution algorithms, require designers to precisely predict the property of applications to be processed. This paper proposes a reconfigurable switch which minimizes buffer overflow in various multimedia applications running on an NoC system. To verify the performance of the proposed system, we performed experiments on various multimedia applications running on embedded systems, such as MPEG4 and MP3 decoder, GPS positioning system, and OFDM demodulator. Experimental results show that buffer overflow has been decreased by 41.8% and 29.0%, respectively, when compared with NoC systems having sub-clusters with mesh or star topology. Power usage has been increased by 2.3% compared with hybrid NoC systems using fixed switches, and chip area has been increased from -0.6% to 5.7% depending on sub-cluster topology.

Analysis of Power Noises by Chip-to-Chip Power Coupling on High-Speed Memory Modules (고속 메모리 모듈에서 칩 간의 파워커플링에 의한 파워 잠음 분석)

  • 위재경
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.10
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    • pp.31-39
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    • 2004
  • This paper illustrates the noise characteristics under chip's core operations according to types of packages and modules for DDR DRAM For analyzing this, the impedance profiles and power noises are analyzed with DRAM chips having commercial TSOP package and commercial FBGA package on TSOP-based DIMM and FBGA-based DIMH In controversy with common concepts, we find that the noise-isolation characteristics of FBGA package are more weak and sensitive on transferred noises than those of the TSOP package. In addition, the simulated results show that the decoupling capacitor locations of modules are more important to control the self and transfer noise characteristics than the lead inductance of the packages. Therefore, satisfying the target spec of the noise suppression and isolation can be achieved through the design of power distribution systems only with considering not only the package types but also the whole module system.