• Title/Summary/Keyword: Power system protection

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Market oriented Typology and Development Directions of Conventional Markets (재래시장의 시장 지향적 분류에 따른 발전방향)

  • Kim, Ju-Yeong;Park, Jeong-Eun
    • Journal of Distribution Research
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    • v.16 no.5
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    • pp.63-84
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    • 2011
  • There are about 1,500 small or large traditional markets in Korea. Those conventional markets have been struggling for survival in rapidly changing market environment with highly intensified competition by accelerating the entrance of the Large-scale Discount Store and Super Supermarket which are managed and supported by Large companies like Samsung and Lotte. The loosing power of conventional markets have threatened the local merchants' survival and have influenced local economics falling down. To create better value for the customers who have more preference for department store and discount stores than conventional markets, conventional markets should have market orientation, which has three sub dimensions; customer orientation, competitor orientation and inter-functional coordinations. First objective of study is to find the appropriate roles of conventional markets in local areas. Second is to find out the market orientation functions for conventional markets to be survival in local markets in the long terms. Finally, this study will suggest some policies for the appropriate types of successful conventional markets considering various local situations. To achieve those objectives, we did the following procedure. First, we review the previous reports and studies of policies for conventional markets and local economy development, and propose some pros and cons of the previous policies. Secondly, we develop a market orientation framework of conventional markets, in which we suggest the developmental types and functions of market-orientation of conventional markets in accordance with the characteristics of local market and economic conditions of local areas. Then we formulate and discuss the study's contributions, managerial implications, and directions for future policy development. Especially for the policy development, we suggest the efficiency and economical effects of policy, human being development and management system, and the role of government and protection of local merchants in the development process.

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Analysis of Transient Potential Rises of Horizontal Ground Electrodes Considering the Frequency-Dependent of Soil (토양의 주파수의존성을 고려한 정보통신설비용 수평접지전극의 과도전위상승 분석)

  • Ahn, Chang Hwan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.2
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    • pp.147-153
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    • 2016
  • The lightning protection of information and communication facilities is very important factor to improve a reliability of the action of these equipment. Especially the transient potential rise of ground electrode being injected with the lightning current is to be a basic data of the dielectric strength for both power and communication facilities so that more accurate analysis should be required. The transient potential rise can be calculated from the ground impedance and the ground impedance is strongly dependent upon the shape of the ground electrode and the frequency-dependence of soil. The Debye's equation which is able to calculate the characteristics of dielectrics is used to analyze the frequency-dependent of soil. Also, the method to calculate the transient potential rise from the ground impedance is specified in this paper. In order to analyze the transient potential rise resulting from calculations with Debye's equation, TLM(transmission line method) and case of ${\rho}$(resistivity)-constant are simulated, respectively. The length of a horizontal ground electrode is 30 m and simulations were performed at 10, 100, $1000{\Omega}{\cdot}m$ with the standard lightning current waveform. In result, the transient potential rise of horizontal ground electrode calculating with Debye's equation is lower than it of other models.

A Study of Children's Statements in sexual violence cases of children less than the age of 13 -Focusing on video-recorded hearsay evidence- (13세미만 아동성폭력 재판에서의 아동진술연구 -영상매체를 통한 전문 증거를 중심으로-)

  • Park, Yeon Ju;Kim, Jung Woo
    • Journal of the Korean Society of Child Welfare
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    • no.55
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    • pp.87-111
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    • 2016
  • This study aimed to examine how video-recorded hearsay statements are taken in trial with regard to testimony of children less than the age of 13 in terms of children's rights, and to assess policy implications for the purpose of improving the current system. This study analyzed the precedents in accordance with their facts and contents. The analysis of the contents dealt with the main issues of trials concerning the sexual violence of children less than the age of 13. Specifically, This study selected precedents dealing with video-recorded hearsay statements, which are children's indirect statement, as core legal issues; examined the credibility(probative power) and admissibility of video-recorded statements; and prepared systemic alternatives in accordance with the United Nations Convention on the Rights of the Child, the international standards for the protection of children's rights. As a result, this study proposed creating and utilizing indicators to assess evidence admissibility and the credibility of video-recoded statements in trial, thus reducing judgement through judges' discretion. Also proposed are new regulations with regard to cross-examination coverage of the hearsay statement of a child in a sexual violence trial of concerning children less than the age of 13. This study suggests an improvement in legal policies, based given that children's rights are more vulnerable than those of adults in trial. Nevertheless, this study is limited in that it selected and reviewed only among precedents that are in the public record.

Radar rainfall prediction based on deep learning considering temporal consistency (시간 연속성을 고려한 딥러닝 기반 레이더 강우예측)

  • Shin, Hongjoon;Yoon, Seongsim;Choi, Jaemin
    • Journal of Korea Water Resources Association
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    • v.54 no.5
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    • pp.301-309
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    • 2021
  • In this study, we tried to improve the performance of the existing U-net-based deep learning rainfall prediction model, which can weaken the meaning of time series order. For this, ConvLSTM2D U-Net structure model considering temporal consistency of data was applied, and we evaluated accuracy of the ConvLSTM2D U-Net model using a RainNet model and an extrapolation-based advection model. In addition, we tried to improve the uncertainty in the model training process by performing learning not only with a single model but also with 10 ensemble models. The trained neural network rainfall prediction model was optimized to generate 10-minute advance prediction data using four consecutive data of the past 30 minutes from the present. The results of deep learning rainfall prediction models are difficult to identify schematically distinct differences, but with ConvLSTM2D U-Net, the magnitude of the prediction error is the smallest and the location of rainfall is relatively accurate. In particular, the ensemble ConvLSTM2D U-Net showed high CSI, low MAE, and a narrow error range, and predicted rainfall more accurately and stable prediction performance than other models. However, the prediction performance for a specific point was very low compared to the prediction performance for the entire area, and the deep learning rainfall prediction model also had limitations. Through this study, it was confirmed that the ConvLSTM2D U-Net neural network structure to account for the change of time could increase the prediction accuracy, but there is still a limitation of the convolution deep neural network model due to spatial smoothing in the strong rainfall region or detailed rainfall prediction.

Analysis of Abnormal Signals for Induction Motor according to Operating Status of Fire Pumps (소방펌프의 운전상태에 따른 유도전동기의 이상 신호 분석)

  • Ku, Bonhyu;Kim, Doo-Hyun;Kim, Sung-Chul
    • Journal of the Korean Society of Safety
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    • v.37 no.4
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    • pp.20-27
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    • 2022
  • This article aims to develop an algorithm that detects fire pump defects by analyzing the current signals of an induction motor, which are triggered by changes in the flow rate and pressure of multistage volute pumps that are used for fire services. The operational status of the pumps was categorized into three: first, normal operation; second, a defect that is caused by a change in the current value; and third, a defect occasioned by a change in current, pressure, and flow rate. When a fire pump was in normal operation, the motor's operating current was measured between 5.06 A and 6.9 A, the flow rate was estimated at 0-0.27 m3/min, and the pressure ranged from 0 to 0.47 MPa. In the event that a defect was caused by an abnormal current value in the motor, it was attributed to the pump's adherence. Furthermore, if there was no source of water, the defect was considered to have been induced by phase-loss operation, no-load operation, or run-stop operation, with the current value of each scenario being measured at > 52.8 A, < 4.13 A, > 45.15 A, and < 3.8 A, respectively, placing its overall range between 0 and 50 A. The sources of defects were detected based on an analysis of the flow rate, pressure, and current, which represent the following causes: air inflow into the casing, inadequate suction of water, and reverse-phase operation, respectively. Each cause entailed the following values: when air seeped into the casing, the pressure was measured at 0.24 MPa irrespective of changes in the flow rate; when there was inadequate suction of water, the pressure was recorded between 0 and 0.05 MPa despite changes in the flow rate; and when the power line's reverse-phase loss was the cause of the defect, the pressure was measured at 0.33 MPa for a flow rate of 0 L/min, and a higher flow rate decreased the pressure to nearly 0 MPa. The results of this study will enable engineers to develop a pump defect detection algorithm that is based on an analysis of current, and this algorithm will facilitate the execution of a program that will control a fire pump defect detection system.

A Data-Driven Approach and Network Analysis of Technological Innovation Resources in SMEs (데이터 기반 접근법을 활용한 중소기업 기술혁신자원의 네트워크 분석)

  • Kyung Min An;Young-Chan Lee
    • Knowledge Management Research
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    • v.24 no.4
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    • pp.103-129
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    • 2023
  • This study aims to analyze the network structure of technological innovation resources in SMEs, especially manufacturing firms, and reveal the differences between innovative and non-innovative firms. The study first analyzes connection centrality, flow-mediated centrality, and power centrality for all firms, and derives structural equivalence through CONCOR analysis. Then, the network structure of innovative and non-innovative firms was compared and analyzed according to innovation performance and creation. The results show that entrepreneurship and corporate innovation strategy have a significant impact on the analysis of technological innovation resources of all firms. According to the CONCOR analysis, the innovation resources of SMEs are organized into seven clusters, which can be defined as intrinsic product innovation resources, competitive advantage promotion resources, cooperative activities resources, information system resources, and innovation protection resources. The network analysis of innovative and non-innovative firms showed that innovative firms focused on enhancing competitiveness and improving quality, while non-innovative firms tended to focus more on existing products and customers. In addition, innovative firms had eight clusters, while non-innovative firms had six clusters, suggesting that innovative firms utilize resources diversely to pursue structural change and new value creation, while non-innovative firms operate technological innovation resources in a more stable form. This study emphasizes the importance of entrepreneurship and corporate innovation strategy in SMEs' technological innovation, and suggests that strong internal efforts are needed to increase innovativeness. These findings have important implications for strategy formulation and policy development for technological innovation in SMEs.

Comparative Study of Security Services Industry Act and Police Assigned to Special Guard Act - Focused on special guards and police assigned to special guard duty - (경비업법과 청원경찰법의 비교 연구 특수경비원과 청원경찰을 중심으로)

  • Noh, Jin-keo;Lee, Young-ho;Choi, Kyung-cheol
    • Korean Security Journal
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    • no.57
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    • pp.177-203
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    • 2018
  • Police Assigned to Special Guard Act was legislated in 1962 to solve issues regarding the protection of various staple industrial installations, and in 2001, the Security Services Industry Act was revised to establish an effective security system for important national facilities. Thereby the Special Guards System was instituted. The current law has two parts, with the Police Assigned to Special Guard System and Special Guards System, and many scholars have actively discussed the appropriateness of the integration of both systems to solve problems caused by a bimodal system. However, in spite of these discussions taking place in the academic world, the idea of unification lost its power when the guarantee of status regulation was established for the police assigned to special guard. Strictly speaking, police assigned to special guard is a self-guard, and a special guard is a contractual guard. So, both of them have pros and cons. Thus, it would be desirable to give a legal, constitutional guarantee for both systems by strengthening each of them and making up for the weakness of each of them rather than trying to unify police assigned to special guard and special guard. To begin this process, we need to revise unreasonable legal provisions of Security Services Industry Act and Police Assigned to Special Guard Act as below. First, since the actual responsibilities of special guards and police assigned to special guard duty are the same, we need to make the facilities which they use equal. Second, legal provisions need to be revised so that a special guard may perform the duties of a police officer, according to the Act on the Performance of Duties by Police Officers, within the facility that needs to be secured in order to prevent any vacancy in the guarding of an important national facility. Third, disqualifications for the special guards need to be revised to be the same as the disqualifications for the police assigned to special guard duty. Fourth, it is reasonable to unify the training institution for special guards and for police assigned to special guard duty, and it should be the training institution for police. On-the-job education for a security guard needs to be altered to more than 4 hours every month just like the one for police assigned to special guard duty. Fifth, for a special guard, it is not right to limit the conditions in their using weapons to 'use of weapon or explosives' only. If one possesses 'dangerous objects such as weapon, deadly weapon, and so on' and resists, a special guard should be able to use their weapon against that person. Thus, this legal provision should be revised. Sixth, penalty, range of fines, and so on for police assigned to special guard duty need to be revised to be the same as the ones for a special guard. If we revise these legal provisions, we can correct the unreasonable parts of Security Services Industry Act and Police Assigned to Special Guard Act without unifying them. Through these revisions, special guards and police assigned to special guard duty may develop the civilian guard industry wholesomely under the law, and the civilians would have a wider range of options to choose from to receive high quality security service.

Ideological Impacts and Change in the Recognition of Korean Cultural Heritage during the 20th Century (20세기 한국 문화재 인식의 이데올로기적 영향과 변화)

  • Oh, Chunyoung
    • Korean Journal of Heritage: History & Science
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    • v.53 no.4
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    • pp.60-77
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    • 2020
  • An assumption can be made that, as a start point for the recognition and utilization of cultural heritage, the "choice" of such would reflect the cultural ideology of the ruling power at that time. This has finally been proved by the case of Korea in the 20th century. First, in the late Korean Empire (1901-1910), the prevailing cultural ideology had been inherited from the Joseon Dynasty. The main objects that the Joseon Dynasty tried to protect were royal tombs and archives. During this time, an investigation by the Japanese into Korean historic sites began in earnest. Stung by this, enlightened intellectuals attempted to recognize them as constituting independent cultural heritage, but these attempts failed to be institutionalized. During the 1910-1945 Japanese occupation, the Japanese led investigations to institutionalize Korean cultural heritage, which formed the beginning of the current cultural heritage management system. At that time, the historical investigation, designation, protection, and enhancement activities led by the Japanese Government-General of Korea not only rationalized their colonial occupation of Korea but also illustrated their colonial perspective. Korean nationalists processed the campaign for the love of historical remains on an enlightening level, but they had their limits in that the campaign had been based on the outcome of research planned by the Japanese. During the 1945-2000 period following liberation from Japan, cultural heritage restoration projects took places that were based on nationalist ideology. People intended to consolidate the regime's legitimacy through these projects, and the enactment of the 'Cultural Heritage Charter' in 1997 represented an ideology in itself that stretched beyond a means of promoting nationalist ideology. During the past 20 centuries, cultural heritage content changed depending on the whims of those with political power. Such choices reflected the cultural ideology that the powers at any given time held with regard to cultural heritage. In the background of this cultural heritage choice mechanism, there have been working trade-off relationships formed between terminology and society, as well as the ideological characteristics of collective memories. The ruling party has tried to implant their ideology on their subjects, and we could consider that it wanted to achieve this by being involved in collective memories related to traditional culture, so called-choice, and utilization of cultural heritage.

A Case Study on the Lean Management Activity in Business-Services Industry (사무.서비스 산업의 린 경영 활동에 관한 사례 연구)

  • Lee, Kang-In;Lee, Soon-San
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.1
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    • pp.189-206
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    • 2012
  • It is urgently requested to innovate the management process of business-service areas in all industry such as financial business, services and manufacturing because of recent business trend - de-manufacturing trend and the weight increment of service in all industries. Many enterprises introduce various management - innovation methodologies in order to meet the rapidly changing business environment. Especially in Korea, it is a vogue to introduce the innovation methodology of the advanced company's. According to this style, the six sigma has been introduced over 10 years since late 1990's and it has become a synonym of innovation indeed. But the result of six sigma introduction has not reached to the level of expectation in its beginning. And the "Lean" have been introduced in Korea in the situation of global financial crisis, economic slump and the pursuit of developing country such as China. Many Korea companies pay attention to the "Lean" innovation activity because the TPS(Toyota Production System) is the matrix of Lean and is the motive power of Toyota growth. In this study, it was analyzed for the evolution course, distinctive features and effects of Lean management and was examined for the difference of Lean management between manufacturing industry and business-service areas. From this results, the characteristics of Lean management in business-service was analyzed. After survey of innovation agent in Korea company, the Lean model of business-service Industry was developed and applied. This study will be worthy to show the right direction to the enterprises which are to apply lean methodologies, or the enterprises which examine lean management for competitive advantages or the peoples who research the same topics.

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Neurotechnologies and civil law issues (뇌신경과학 연구 및 기술에 대한 민사법적 대응)

  • SooJeong Kim
    • The Korean Society of Law and Medicine
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    • v.24 no.2
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    • pp.147-196
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    • 2023
  • Advances in brain science have made it possible to stimulate the brain to treat brain disorder or to connect directly between the neuron activity and an external devices. Non-invasive neurotechnologies already exist, but invasive neurotechnologies can provide more precise stimulation or measure brainwaves more precisely. Nowadays deep brain stimulation (DBS) is recognized as an accepted treatment for Parkinson's disease and essential tremor. In addition DBS has shown a certain positive effect in patients with Alzheimer's disease and depression. Brain-computer interfaces (BCI) are in the clinical stage but help patients in vegetative state can communicate or support rehabilitation for nerve-damaged people. The issue is that the people who need these invasive neurotechnologies are those whose capacity to consent is impaired or who are unable to communicate due to disease or nerve damage, while DBS and BCI operations are highly invasive and require informed consent of patients. Especially in areas where neurotechnology is still in clinical trials, the risks are greater and the benefits are uncertain, so more explanation should be provided to let patients make an informed decision. If the patient is under guardianship, the guardian is able to substitute for the patient's consent, if necessary with the authorization of court. If the patient is not under guardianship and the patient's capacity to consent is impaired or he is unable to express the consent, korean healthcare institution tend to rely on the patient's near relative guardian(de facto guardian) to give consent. But the concept of a de facto guardian is not provided by our civil law system. In the long run, it would be more appropriate to provide that a patient's spouse or next of kin may be authorized to give consent for the patient, if he or she is neither under guardianship nor appointed enduring power of attorney. If the patient was not properly informed of the risks involved in the neurosurgery, he or she may be entitled to compensation of intangible damages. If there is a causal relation between the malpractice and the side effects, the patient may also be able to recover damages for those side effects. In addition, both BCI and DBS involve the implantation of electrodes or microchips in the brain, which are controlled by an external devices. Since implantable medical devices are subject to product liability laws, the patient may be able to sue the manufacturer for damages if the defect caused the adverse effects. Recently, Korea's medical device regulation mandated liability insurance system for implantable medical devices to strengthen consumer protection.