• 융합보안논문지
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• 제18권2호
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• pp.11-17
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• 2018

Lamport 일회용 패스워드(OTP)는 고정된 패스워드 그리고 패스워드의 사전공유라는 단순 패스워드가 지니는 문제점을 해결하기 위해 해시체인에 기반을 두고 있다. 하지만 Lamport 방식은 길이가 유한한 해시체인의 해시값을 OTP로 사용하기 때문에 해시체인을 구성하는 해시값들을 모두 소진한 이후에는 새로운 해시체인의 루트 해시값을 재 등록해야 한다는 단점을 가지고 있다. 이 같은 단점을 해결하기 위해 여러 연구가 진행되었으나 증명자와 검증자에 대한 계산 부담이 증가하는 등 새로운 단점이 노출되었다. 따라서 본 논문에서는 Lamport 방식의 장점을 유지하면서 동시에 단점을 해결하기 위해 기존 Lamport 방식 OTP의 핵심인 하나의 긴 해시체인 대신에 여러 개의 짧은 해시체인을 중첩 구성하는 새로운 방식의 OTP를 제안하고 비교 분석한다.

• Nuclear Engineering and Technology
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• 제51권2호
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• pp.444-452
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• 2019

To assess the availability of a nuclear power plant's dynamic systems, it is necessary to consider the impact of dynamic interactions, such as components, software, and operating processes. However, there is currently no simple, easy-to-use tool for assessing the availability of these dynamic systems. The existing method, such as Markov chains, derives an accurate solution but has difficulty in modeling the system. When using conventional fault trees, the reliability of a system with dynamic characteristics cannot be evaluated accurately because the fault trees consider reliability of a specific operating configuration of the system. The dynamic reliability graph with general gates (DRGGG) allows an intuitive modeling similar to the actual system configuration, which can reduce the human errors that can occur during modeling of the target system. However, because the current DRGGG is able to evaluate the dynamic system in terms of only reliability without repair, a new evaluation method that can calculate the availability of the dynamic system with repair is proposed through this study. The proposed method extends the DRGGG by adding the repair condition to the dynamic gates. As a result of comparing the proposed method with Markov chains regarding a simple verification model, it is confirmed that the quantified value converges to the solution.

• Advances in nano research
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• 제12권4호
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• pp.375-386
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• 2022

Synthesis of acrylate-based dispersion resins involves many parameters including temperature, ingredients concentrations, and rate of adding ingredients. Proper controlling of these parameters results in a uniform nano-size chain of polymer on one side and elimination of hazardous residual monomer on the other side. In this study, we aim to screen the process parameters via Internet of Things (IoT) to ensure that, first, the nano-size polymeric chains are in an acceptable range to acquire high adhesion property and second, the remaining hazardous substance concentration is under the minimum value for safety of public and personnel health. In this regard, a set of experiments is conducted to observe the influences of the process parameters on the size and dispersity of polymer chain and residual monomer concentration. The obtained dataset is further used to train an Adaptive Neural network Fuzzy Inference System (ANFIS) to achieve a model that predicts these two output parameters based on the input parameters. Finally, the ANFIS will return values to the automation system for further decisions on parameter adjustment or halting the process to preserve the health of the personnel and final product consumers as well.

• Journal of Information Technology Applications and Management
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• 제31권2호
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• pp.51-66
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• 2024

Internet of Things (IoT) is a term that has been introduced in recent years, and it defines objects being able to connect and transfer data through the internet. Although some IoT-related products are currently available in the market, there are still some IoT problems that need to be overcome, such as the technology issues and lack of confidence and understanding of IoT. This study aims to analyze the influential factors in building successful IoT system for smart supply chain. This study develops the Analytic Hierarchy Process (AHP) to evaluate the influential factors in IoT. This study finds that tangible factors (Technology, Value and Connectivity) are more important than the intangible factors (Operation and Intelligence). Finally, this study concludes that after enterprises build a good IoT connectivity system, it is essential to combine this with good IoT technology to create a successful IoT environment. The findings may help practitioners implement IoT in smart supply chains to deal with disruptions, risks and vulnerabilities in the post-pandemic era.

• 산업공학
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• 제13권3호
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• pp.444-454
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• 2000

Due to the improvement of modern information technologies, sharing stock information among the supply chain members is a common practice nowadays. Many companies are planning to adopt the information systems to possess the real-time shared stock information. Thus, it is needed to quantify the value of shared stock information. The purpose of this paper is to evaluate the value of the shared stock information for two-echelon distribution systems. Existing reorder policies can be classified into installation stock policies and echelon stock policies. Since installation stock policies do not utilize the shared stock information, and both classes of policies may show poor performances for distribution systems, we cannot evaluate the value of the shared stock information with the existing policies. Thus, we provide a new type of reorder policy, named order risk policy. We define the order risk using marginal analysis, and prove the optimality. Through computational experiment that compares the order risk policy with the existing policies, it is shown that a significant cost reduction is achieved with the effective utilization of the shared stock information. We also show the effect of the system characteristics on the value of the shared stock information.

• 유통과학연구
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• 제22권7호
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• pp.107-117
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• 2024

Purpose: Consumers have become more interested in eating organic food in recent decades because of the effect of merchants' advertising. Eating organic food is also shown to strengthen immunity, especially during the recent COVID-19 pandemic. However, consumers may find it more difficult to choose organic food retailers than to purchase conventional goods. This is because of the uncertainty characterizing the process of selecting organic food retailers, despite the growing rivalry across supermarket chains that sell organic goods. This study explores how consumers' perceived image (social responsibility and ability image) of organic food stores affects consumer loyalty. Research design, data and methodology: The data for the analysis were collected using Macromill Embrain, an online research service agency. The data were analyzed using SPSS 26 and Smart PLS 4.0. Results: Based on structural equation modeling, the findings of the study demonstrate that store image positively impactsstore loyalty, and that the mediator (perceived value) affects the relationship between the two variables. Conclusions: Organic food stores must understand consumers to improve store loyalty. Efforts such as providing a user community that enables joint behavior by sharing experiences among customers or launching campaigns to improve consumers' perceived brand identity can increase store loyalty.

• 한국식생활문화학회지
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• 제26권5호
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• pp.417-428
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• 2011

To promote use of nutrition labels, degrees of awareness, use, and satisfaction of nutrition labeling on eating-out menus were investigated by a self-recorded questionnaire from May to July 2010 in 629 participants who visited four bakery chains (n=409) and three ice-cream chains (n=220) located in Daejeon. Of the subjects 53.4% were female, 68.8% aged 20~29 years, and 59.3% visited bakery or ice-cream stores 1~3 times per month. Only 38.2% of participants had knowledge of nutrition-labeling mandates for eating-out menus, and 74.9% had seen labels before in bakery and ice-cream stores. Most subjects understood calorie amount and daily value of sodium very well, but they failed to understand the meaning of daily value. Only 21.2% of the subjects understood nutrition label information completely. Of the participants, 46.7% read nutrition labels in bakery or ice-cream stores when purchasing. Among the subjects who read the labels, 77.2% (36.1% of total subjects) referred to the label information when selecting a menu and 46.9% (21.9% of total subjects) had experienced altering their menu choice based on the information. Exactly 53.3% of subjects answered they did not read nutrition labels since they were not interested or had no time, or because the labels were not noticeable. Satisfaction of the place, timing, and format of nutrition labels at bakery and ice-cream stores fell below average overall. Many subjects wanted trans fat and cholesterol to be added to the labels. In conclusion, degrees of perception, use, and satisfaction of nutrition labels at bakery and ice-cream stores were still low. More effective publicity and consumer education about nutrition labeling will be necessary, and bakery or ice-cream companies should make efforts to improve nutrition labeling such as providing format and place.

• Journal of Korea Trade
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• 제25권3호
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• pp.65-86
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• 2021

Purpose - This paper empirically investigates the relationship between the corporate value chain and performance of non- financial businesses of South Korean stock market companies. It aims to explore the evidence that can be used to infer the relationship between value chains and corporate performance in the case of firms forming a value chain with other companies with the means of an equity investment or a special business relationship. Design/methodology - Non-financial corporations listed from 2011 to 2017 on the securities market of South Korea are analyzed. The data used for analysis are found for transactions with the related party by year for all the corporations of non-financial industries in the securities market. Multiple analysis attempts are conducted including the relationship between the value chain and productivity, corporate value, risk-adjusted corporate value, and mediation effects of productivity. The empirical model employs sixteen variables including the value chain index which identifies its impact on various aspects of business performances. Findings - The results of this study clearly supports the phenomenon that corporate productivity and value are enhanced when the corporation expands its value chain established with domestic related firms and overseas companies. Such a positive effect is statistically significant even after the possible risk factors that accompany the expansion of value chain were considered, and productivity plays the role as a medicating variable in the effect of the value chain on the corporation values. Originality/value - The findings of this study confirms that domestic companies' expansion of their value chain centered on the related firms overseas that helped them in terms of the maximization of their productivity and corporate values. This study shows that Korean government's policy on expanding the corporate GVC can enhance the productivity and value of firms. The expansion of value chain and its impact on business performance has not been explored thoroughly, although it is getting more and more important in the global trade operation.

• 유통과학연구
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• 제14권4호
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• pp.127-134
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• 2016

Purpose - Value chain in agriculture refers to direct and indirect activities related to value-added process from raw materials to final products in agricultural industries. In recent years, value chain analysis has become more important in the area of agricultural development. This article reviews the concept and importance of value chain analysis in the context of agricultural development and attempts to suggest improvement strategies. Research design, data, methodology - A literature survey was conducted for value chain analysis for agricultural development. The case of agro-value chain in Cambodia was deeply analyzed based upon interviews with government officers and related experts. Results - It seems that agro-value chain in developing countries are not well developed and does not carry out appropriate functions, compared to developed countries. Because value adding facilities, such as storage, processing and packing plants, milling plants, and etc. are not sufficiently constructed, the quality of agricultural products is low. Especially developing countries may loose opportunities to increase value of their product by exporting their agricultural products as raw materials to neighboring countries. Value adding process is also mainly controlled by traders in local markets or wholesale markets in urban areas. Farmers therefore can get lower share of final value of agricultural products compared to the shares paid to traders. Lastly it is argued that governments of developing countries do not play an active role in developing value chains and do not carry out coordinating functions in an effective and efficient manner. Conclusions - The first step to improve agro-value chain in developing countries is to identify and analyze value chain structure of agricultural products and to make development strategies and implementation programs. For improving value chain of agricultural products in developing countries, it is required to provide not only plans for constructing hardwares, such as wholesale markets, storage facilities, processing and packing plants, and etc., but also plans for improving softwares, such as measures for improving product quality and safety, setting up grade and standard, providing market information, and nurturing producer cooperatives.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2003년도 춘계학술대회
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• pp.222-229
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• 2003

In the process of global transportation, many value chains which have different business process, system and technology level respectively are connected to each other. To obtain end-to-end visibility of transportation, these kind of discrepancy has to be solved appropriately. In this paper, the realization of global visibility is discussed in three point of view such as 'Data Sourcing', 'System integration' and 'System Operation'. First, the data sources of global visibility are described especially from the point of enterprise applications view, and then system integration is presented using various current e-commerce technologies for example XML, EDI and so on. Finally, flexible operation of visibility function is suggested which satisfies different goals of each value chain.