• Convergence Security Journal
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• v.22 no.1
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• pp.71-79
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• 2022

The smart grid system has emerged to maximize energy efficiency through real-time information exchange between power providers and consumers by combining information technology and power supply systems. The authentication schemes using blockchain in a smart grid system have been proposed, which utilize an edge server's architecture to collect and store electric power-related information and process data between a central cloud server and smart grid-IoT devices. Although authentication schemes are being proposed to enhance security in the smart grid environment, many vulnerabilities are still reported. This paper presents a new mutual authentication scheme to guarantee users' privacy and anonymity in a smart grid based on edge computing using blockchain. In the proposed scheme, we use the smart contract for the key management's efficiency, such as updating and discarding key materials. Finally, we prove that the proposed scheme not only securely establishes a session key between the smart grid-IoT device of the user and the edge server but also guarantees anonymity.

• Journal of Digital Convergence
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• v.17 no.7
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• pp.131-138
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• 2019

The world's electricity production ratio is 40% for coal, 20% for natural gas, 16% for hydroelectric power, 15% for nuclear power and 6% for petroleum. Fossil fuels also cause serious problems in terms of price and supply because of the high concentration of resources on the earth. Solar energy is attracting attention as a next-generation eco-friendly energy that will replace fossil fuels with these problems. In this study, we test the charge-operation plan and the discharge operation plan for peak-cut operation by applying the maximum power demand reduction simulation. To do this, we selected the electricity usage from November to February, which has the largest amount of power usage, and applied charge / discharge logic. Simulation results show that the contract power decreases as the peak demand power after the ESS Peak-cut service is reduced to 50% of the peak-target power. As a result, the contract power reduction can reduce the basic power value of the customer and not only the economic superiority can be expected, but also contribute to the improvement of the electric quality and stabilization of the power supply system.

• The Journal of Fisheries Business Administration
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• v.31 no.1
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• pp.115-133
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• 2000

The policy of suppling tax-exempt fishery oil in Korea has a history of almost 40 years, which was initiated by the National Federation of Fisheries Cooperatives in 1965. In 1999 the volume of fishery oil supplied to the earning fishermen and fishing entrepreneurs amounted to 8,390 thousand DM, 500 billion won in total. This paper analyzes the oil supplying system to fishermen in Korea and shows that the structural obstacles to the stable provision of fishery oil lies in the ineffective bargaining power (fixing price). Provided that the NFFC as a buyer, which is not equipped with the storage facilities for oil bids for a unit-price contract of fishery oil, there exists a possibility of collusion among 5 local oil refineries corporations to influence the oil price, making it difficult to reach a resonable price of oil. Though the international bids and direct imports following the liberalization of oil imports would help lower the unit price, purchasing and importing the oil out of season at a lower price would not be guaranteed without the oil storage facilities. Furthermore, the current supply system of oil is quite vulnerable to the extraneous factors and, say when the oil price soars unpredictably, it is almost impossible to supply low - priced fishery oil to fishermen. The National Federation of Fisheries Association of Japan(Zengyoren), for instance, possesses 10 oil storage facilities, which had been built across the country during the last 20 years (1964-1984). The storage capacity of these facilities reaches 0.6million DM(by kind, 0.56million DM for A heavy oil, 38thousand D/M kerosene, 5thousand D/M for diesel fuel oil). Allowing no intermediary of production associations(fisheries cooperatives) the NFFA's capacity for keeping oil in reserve rises much higher. As these storage facilities can keep the oil amounting to as much as of 70 days demand in reserve, a stable supply of fishery oil on favorable terms is secured. In contrast with Japan case, unequipped with the storage facilities for fishery oil, Korea does not have much bargaining power for bringing down the price of fishery oil. To make matters worse, the oil storing capacity of the member cooperatives is the volume of only 8 days demand. In case the oil price rises, it is almost impossible to supply the oil to the fishermen at a price lower than the price risen.

• Korean Journal of Poultry Science
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• v.20 no.2
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• pp.107-114
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• 1993

The structure change in the broiler industry of Korea has been taking place very rapidly toward the direction of integrated production and marketing system. During the course of the evolution into the integrated structure, however, a number of small business entities, uncountable nationally but a minimum of a dozen, that previously engaged in the supply of production factors or live bird transaction also tended to get involved in the new system as a disguised or pseudo-integrator, having brought a lot of problems not only to the farmers but also to the development of integrated structure. The pseudo-integrator is generally characterized by limited functions in such a way of supplying chicks and feeds to and collecting grown birds from farmers under the contract at a fixed farmer's payment in practically the same pattern as a partial or quasi-integration, which intends to act as if an integrator in a stratagem to simply enjoy a margin simply from selling supplies and buying products for a certain period of time. The grower making a contract with appears to be a farmer who used to be an Independent and speculating but not able to join in the normal system of evolving integration. The problems of a pseudo-integrator center on the financial loss to a contract farmer, because the falsified integrator has to become easily bankrupt and run away when the price of live broiler continually stays below the cost of production, even though he is able to make a tremendous profit otherwise which is the real purpose of the operation for. It is true that the volatile market, fluctuating the price up more than doubled in a month and down to a half in a few weeks, makes the pseudo-integrator find the room for such a fraudulence. In addition, its activity also adversely affect the evolution of the integration due to rather negative image on structure change in general. It is recommended that the farmers need to better understand the real picture of the integrated system so as not to be swindled by a disguised, small scale agribusiness agent. By the same token, it is also equally required to have the whole industry integrated completely as early as possible. The Joint effort to get rid of pseudo-integrators' problems shall be put for the industry development moving toward the integration. No doubt a pseudo-integrator must be a temporary player for chance emerging during the course of structure change into the integrated, though.

• Korean Journal of Construction Engineering and Management
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• v.13 no.6
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• pp.153-164
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• 2012

Since the sub-prime mortgage crisis from the US in 2008, Korean housing market has plummeted. However, Korean local lease contract, Chonsei, price has been increasing. This increase of Chonsei price can be a threat to the low-income people because most of them prefer to live at the house with a Chonsei contract. In order to solve this problem, the Korean Government implemented several Chonsei policies to secure low-incomers' residence by decreasing the price of Chonsei; however, due to the lack of understanding on housing and Chonsei market, Korean government policy seemed to fail on getting effective results. In the housing and Chonsei market, there are many stakeholders with their own interest, hence, simple thoughts about housing and Chonsei market, such as more house supply will decrease house price, would not work in a real complex housing market. In this research, we suggests system dynamics conceptual model which consists of causal-loop-diagrams for the Chonsei market as well as the housing market. In addition, we tries to explain why the policy did not work effectively using the examples from the government's past measures. In results, Chonsei price has its own homeostasis characteristic and different price movement with housing price in the short and long term period. Unless government does not have a structural causation mind in implementing policies in the real estate market, the government may not attain intended effectiveness on both markets.

• Culinary science and hospitality research
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• v.18 no.3
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• pp.46-57
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• 2012

This study aims to analyze how the perception of a food purchasing system affects non-financial performance and job satisfaction among the kitchen employees of contract foodservice companies in Taegu Gyeongbuk area. By a convenience method, 197 copies(85%) out of 230 copies of the questionnaire were used for analysis. For data processing, the SPSS WIN Version 14.0 statistical package program was used and the frequency analysis reliability analysis, factor analysis were conducted so the hypothesis was verified through the multiple regression analysis. The results are as follows: First, the perception of a food purchasing system affected job satisfaction as a whole, which was significant in food ingredients management factors of sub-hypothesis1-2. Second, the perception of a food purchasing system affected non-financial management performance, which was significant in food ingredients management factors of sub-hypothesis2-2, and food ingredients supply and demand factors of sub-hypothesis2-3. Third, job satisfaction affected non-financial management performance of a company as suggested by hypothesis 3. From these results, it was found that kitchen employees' perception of a food purchasing system can induce their positive attitude, which exerts positive effects on business performance.

• The Korean Society of Law and Medicine
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• v.13 no.2
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• pp.79-113
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• 2012

This study focuses on the protection of trial subjects, who participate in clinical trials for new drug. It takes long time to develop new drugs and the clinical trials are required. Usually, pharmaceutical company, which develop new drug, request a research institution(usually, hospital) to investigate the examination of security and side effects of new drug. The institution recruit trial subject to participate in the trials. The contract for clinical research of investigational new drug is concluded between the pharmaceutical company and the institution. This thesis studies the legal regulations for protection of participants of clinical research for new drug. In this respect the first matter of this study is to seek which relation between pharmaceutical firm and participants of clinical trials. Especially, there is a question which the trial subject is entitled to demand the pharmaceutical company which requested clinical trials the institution to supply the investigational new drug, after the contract for clinical trials had terminated or cancelled. This study take into account the liability of the pharmaceutical company to trial subject. Secondly, it is researched the roles and authority of Institutional Review Board(IRB). IRB is Research Ethics Committee of the institution, in which clinical trials for new drug are conducted. According to the rule of Korea good clinical practice(KGCP), IRB is the mandatory organization which is authorized to approve, secure approval or disapprove the clinical trials for investigational new drug in the institution. The important roles are the review of ethical perspective of trial research and the protection of trial subject. Thirdly, this paper focuses if the participants are to be paid for the participation for clinical research. This is ethical aspect of clinical trials. It is resonable that the participant is reimbursed for expenditure such as travels, and other expenses incurred in participation in trials. It is not allowed that the benefit of clinical trials is paid to trial subject. The payment should not function as financial inducements for participations of trials. Finally, the voluntary consent of the trial subject is required. The institution ought to inform the subject, who would like to participate in trials, and it ought to received informed consent in writing for subject. In this regard, it is matter that trial subject has ability of consent. It is principle that the subject as severely psychogeriatric patient has not ability of consent. However, it is required that not only healthy people but also patients are allowed to take part in clinical trials of new drug, in order to confirm which the investigation new drug is secure. Therefore there are cases, in which the legal representative of subject consent the participation of the trials. In addition, it is very important that the regulations concerning clinical trials of new drug is to be systematically well-modified. The approach of legal and political approach is needed to achieve this purpose.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.226-239
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• 2007

The purpose of this study was to identify the problems related to the purchasing processes of school foodservices that should be corrected for the food service safety, by examining the purchasing processes and the status of supplier selection. A questionnaire was given to 300 dietitians working at self-operated food services. Ninety-eight responses, excluding incomplete answers, were used for the statistical analysis. The survey consisted of three parts: the general characteristics of the school foodservice and dietitian, purchasing processes and supplier selection, and the purchase specifications. We found that 84% of the contract was made by informal purchasing, and the contract period was 6 months or one year. For supplier selection, problems related to the document screening systems were the superficiality of the content(45.7%) and the absence or lack of clarity of the appraisal criteria(34.8%). The important factors for the facility and equipment standards of suppliers were included unclear evaluation methods for content(41.1%) and inappropriate appraisal lists(21.1%), while unclear evaluation methods for content(41.9%) and absence or lack of clarity of the appraisal criteria(20.4%) were the problems pertaining to the supplier evaluation checklist. When using the Food Labeling Standards to select suppliers, confirmation of the sell-by date and the storage method had the highest score at 3.85 out of 5. For supplier selection, only 25% of the contract was made by using the purchase specifications. The levels of satisfaction of with Kimchi and rice cakes suppliers were significantly different according to employment type and educational background, respectively. Depending on working experiences, satisfaction was significantly different for the use of document screening, as a standard for the selection and management of suppliers, and for the facility and equipment standards of suppliers, The use of purchase specifications was different by employment type, while the use of purchase specifications for contracts was different by working experience. These results imply that the specialization of suppliers is necessary to unsure food safety. Therefore, the objective methods to evaluate the suppliers should be developed by the government, and appropriate education programs for dietitians should be prepared to enhance the utilization of purchase specifications.

• Korea Trade Review
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• v.42 no.1
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• pp.69-97
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• 2017

This study purpose to examine the importer's risks that may arise from origin investigation by Customs authorities. We have drawn the important factors affecting the application of FTA preferential tariffs and divided the stages from the conclusion of the contract for the importer to the undergoing origin investigation. In addition, we demonstrate empirically that the risks that arise in areas where importers are difficult to control exist. As a management method of the uncontrollable risk from the importer, we have provided the methods that the seller stipulated the seller's responsibility in the trade contract, prepared for situations in which no one was responsible, and formulated a friendly and cooperative supply chain. Even if the seller's liability is clarified in the contract for sale, the risk of the investigation into the origin of the imported goods is not completely eliminated. This is because, under the current agreement and system, there is no way for the customs authority of the contracting party of the FTA to claim compensation for damages incurred by importers due to breach of agreement such as not returning the result of the origin verification. Importers are subject to customs duties, but there may actually be situations in which no one is responsible for them.

• Journal of Korea Trade
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• v.25 no.1
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• pp.152-168
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• 2021

Purpose - This paper has an objective to suggest reasonable criteria in choosing Incoterms 2020 rules for efficient and effective logistics management in that the Incoterms rules affect not only the rights and obligations of the parties to the sales contract but also the control and management of logistics system and transaction costs in the transaction. Design/methodology - An analysis of the various factors is needed to assess the positive or negative impact on global value chain in choosing Incoterms rules from a total logistics view. This study analyzes the impact of which the content of individual incoterms rules can have on the operation of international logistics systems under the global value chain from a strategic perspective to suggest reasonable criteria for selection of Incoterms rules depending on the transaction situation. Findings - Results of this study shows that consideration of various aspects which includes the characteristics of the products, logistics capabilities, infrastructure, transaction volume, operational cost, customs regulations, tax and accounting should be reflected in choosing the appropriate Incoterms rules. Therefore, in order to minimize the total cost and improve logistics performance, it may be helpful to develop a decision support model which allows users to select appropriate Incoterms rules based on various influencing factors. Originality/value - This Study is different from previous research which has mainly focused on the rights and obligations of the parties to the transaction regarding the transfer of risks and costs under the Incoterms. In addition, this study has significance in that it provides implications for export and import companies that can be able to use Incoterms as a strategic tool to efficiently manage the global value chain and improve supply chain performance.