• 제목/요약/키워드: supply chain system

검색결과 860건 처리시간 0.026초

상태기반 RFID 인증 프로토콜 (Status-Based RFID Authentication Protocol)

  • 유성호;김기현;황용호;이필중
    • 정보보호학회논문지
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    • 제14권6호
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    • pp.57-68
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    • 2004
  • 근래에, Radio Frequency Identification (RFID) 시스템은 생산, 공급망관리, 재고관리 등의 분야에서 유용하게 사용될 반한 기술로서 산업계에서 많은 관심을 받고 있다. 가까운 미래에는 저렴한 가격의 RFID 태그나 스마트 라벨이 현재 사용되고 있는 바코트 대신 상품관리에 활용될 것으로 알려져 있다. 그러나 작고 값싼 RFID태그의 생산과, 사용자 프라이버시 보호를 위한 안전한 인증프로토콜의 개발은 아직 해결해야 할 문제들이다. 반도체 기술의 발전에도 불구하고, 태그의 계산과 저장능력은 제한되어 있으므로 기존 다른 시스템에 적용되던 암호시스템의 적용은 현실적으로 쉽지 않다. 그러므로 RFID시스템에서 사용할 수 있도록 더 작은 저장 공간과 더 작은 계산량이 소요되는 새로운 프로토콜의 개발이 필요하다. 본 논문에서는 위치트래킹 공격과 스푸핑 공격에 안전한 RFID인증 프로토콜을 제안한다. 제안한 프로토콜은 기존 인증프로토콜보다 데이터베이스에서의 계산랑이 상당히 감소하였으므로 프라이버시 보호를 위한 실질적인 해결책으로 사용이 가능하다.

분해옵션 포함 서비스부품 로트사이징 휴리스틱 (A Heuristic for Service-Parts Lot-Sizing with Disassembly Option)

  • 장진명;김화중;손동훈;이동호
    • 산업경영시스템학회지
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    • 제44권2호
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    • pp.24-35
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    • 2021
  • Due to increasing awareness on the treatment of end-of-use/life products, disassembly has been a fast-growing research area of interest for many researchers over recent decades. This paper introduces a novel lot-sizing problem that has not been studied in the literature, which is the service-parts lot-sizing with disassembly option. The disassembly option implies that the demands of service parts can be fulfilled by newly manufactured parts, but also by disassembled parts. The disassembled parts are the ones recovered after the disassembly of end-of-use/life products. The objective of the considered problem is to maximize the total profit, i.e., the revenue of selling the service parts minus the total cost of the fixed setup, production, disassembly, inventory holding, and disposal over a planning horizon. This paper proves that the single-period version of the considered problem is NP-hard and suggests a heuristic by combining a simulated annealing algorithm and a linear-programming relaxation. Computational experiment results show that the heuristic generates near-optimal solutions within reasonable computation time, which implies that the heuristic is a viable optimization tool for the service parts inventory management. In addition, sensitivity analyses indicate that deciding an appropriate price of disassembled parts and an appropriate collection amount of EOLs are very important for sustainable service parts systems.

수소분리 및 정제를 위한 PSA(Pressure Swing Adsorption)시스템 안전성향상에 관한 연구 (A Study on the Safety Improvement of PSA System for Hydrogen Separation and Purification)

  • 오상규;이슬기;이준서;마병철
    • 한국가스학회지
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    • 제26권1호
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    • pp.7-19
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    • 2022
  • 일반적으로 수소의 정제는 화학적, 물리적인 방법을 통해 수행한다. 여러 종류의 정제방법 중 현재는 정제 용량 및 경제성이 가장 우수한 PSA(Pressure Swing Adsorption)를 이용한 정제방법이 가장 널리 사용되고 있다. 국내도 대부분 PSA를 이용하여 자동차 및 발전용 수소 연료전지 등에 사용하는 수소를 정제하고 있다. 기존 석유화학 단지중심의 부생수소는 운송 등의 어려움이 있다. 정부는 도시가스 공급망과 연계하여 소비지에서 직접 수소를 생산하는 수소추출기 설치 계획하고 있으며, 기업들도 이와 관련된 연구 및 실증 설비를 속속 설치하고 있는 실정이다. 유럽 등은 최근 PSA와 관련된 안전기준을 마련하여 시공 및 운영단계에서 체계적인 안전관리를 위한 노력을 기울이고 있으나, 국내는 PSA와 관련된 안전기준 마련이 아직까지는 미흡하다. 본 연구에서는 기존 PSA를 운영하고 있는 회사의 설문 및 위험성평가를 통해 기존설비의 문제점을 파악하고, 국외 기술기준에 이를 포함한 국내 기술기준을 작성하여 신규설치 및 기존 운영되고 있는 PSA시스템의 안전을 도모하고자 한다.

Research on the Relationship Between Social Capital and Enterprise Performance in Supply Chain Environment

  • Li, Jian;Lee, Sang-Chun;Jeong, Ha-Eun
    • Journal of Korea Trade
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    • 제24권4호
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    • pp.34-48
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    • 2020
  • Purpose - The rapid rise of e-commerce enterprises has led to the development of the logistics industry. At the same time, some enterprises are motivated by the interests to start reducing costs and inputs, which on the contrary leads to low quality of service, thus reducing customer satisfaction. In recent years, vicious competition, violent express delivery and lack of professionalism in the logistics market have led to high annual customer complaint rate, which has resulted in the company losing many loyal customers, but also unable to obtain new customers. Therefore, to pay attention to and understand the psychological needs of customers and improve the quality of logistics distribution service has become a pressing problem for Every express company. Design/methodology - By analyzing the problems existing in logistics distribution of express companies, this paper explores various factors affecting customer satisfaction and takes consumer sentiment as a mediating variable. Through questionnaires to collect relevant data, put forward hypotheses for empirical analysis, use two different software including SPSS 21.0 and AMOS 21.0 to analyze the information, draw conclusions and make recommendations. Findings - According to the above research results, the reliability, convenience, efficiency, professional can have a positive impact on customer satisfaction through the mediating effect of their sentiment, convenience and professional on consumer sentiment and satisfaction are more significant. Originality/value - This paper the establishment of distribution service indicators related to customer satisfaction and empirical analysis can not only enrich and supplement the distribution service quality indicator system studied by the former, but also provide a theoretical basis for future research.

Towards water-efficient food systems: assessing the impact of dietary change and food waste reduction on water footprint in Korea

  • Qudus Adeyi;Bashir Adelodun;Golden Odey;Kyung Sook Choi
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.184-184
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    • 2023
  • Globally, agriculture is one of the largest consumers and polluters of water resources, contributing to the unsustainable use of limited water resources. To reduce the resource use and environmental footprints associated with current and future food systems, researchers and policy makers have recommended the transition to sustainable and healthier diets and the reduction of food loss and waste along the food supply chain. However, there is limited information on the synergistic effects and trade-offs of adopting the two measures. In this study, we assessed the water-saving potential of the two measures in South Korea using environmentally extended input-output relying on the EXIOBASE database for the reference year 2020, along with scenario analysis to model the potential outcomes. Specifically, we analyzed scenarios where meat consumption was reduced by 30% and 50% and in combination with a 50% reduction in food waste at the consumption stage for each scenario. According to our findings, by considering individual measures of dietary change and food waste reduction, shifting to a diet with 30% and 50% less meat consumption could lead to reduction in water footprint by 6.9% and 7.5%, respectively, while 50% reduction in food waste at the consumption stage could save about 14% of water footprint. However, the synergistic effects of the two measures such as 30% less meat consumption and 50% food waste reduction, and 50% less meat consumption and 50% food waste reduction result to 20% and 24% reductions in water footprint, respectively. Moreover, our findings also showed that increasing food consumption with high environmental impacts could promote resources use inefficiency when waste occurs. Thus, policy strategies that address synergistic effects of both dietary change and food waste reduction should be strengthened to achieve sustainable food system. International and national policies can increase resource efficiency by utilizing all available reduction potentials while considering strategies interactions.

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An Integrated Analysis of Recent Changes in Year-on-Year Consumer Price Index and Aggregate Import Price Index in Republic of Korea through Statistical Inference

  • Seok Ho CHANG;Soonhui LEE
    • 아태비즈니스연구
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    • 제14권1호
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    • pp.365-379
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    • 2023
  • Purpose - Our previous study (Chang & Lee, 2023) presented observations on the recent changes in the year-on-year (YoY) Consumer Price Index (CPI) of the Republic of Korea (ROK) after the COVID-19 pandemic. The purpose of this article is to present an integrated analysis and interpretation of the recent changes in CPI and the Aggregate Import Price Index (IPI) by incorporating recent data, specifically data from September 2022 to December 2022. Design/methodology/approach - This study collected CPI (YoY) data in the ROK from January 2019 to December 2022 using e-National Indicator System provided by the ROK. Statistical analysis was employed to analyze the data. Findings - First, we confirm the extended results of the existing study by Chang and Lee (2023). Second, we demonstrate that the Aggregate IPI in ROK increased significantly in 2022 compared to 2021. We then provide an integrated interpretation on the significant increase in CPI and aggregate IPI in ROK, which complements Chang and Lee (2023) that limits their discussion to YoY CPI. Moreover, we show that the IPI of the semiconductor in ROK decreased significantly in 2022 compared to 2021. Research implications or Originality - Our results provide important insights into the recent changes in the CPI in the ROK. The results suggest that these changes can be partially attributed to various factors, such as the global supply chain disruptions resulting from the spread of the COVID-19 pandemic and the prolonged war between Russia and Ukraine, the side effect of quantitative easing by the US Federal Reserve, heat waves and droughts caused by climate change in ROK, a surge in demand following a gradual daily recovery, US-China trade conflict, etc. Our study shows statistically comprehensive results compared to the studies that limit their discussion to YoY average growth rate.

민간기업을 위한 물리적 기후리스크 추정 연구 (Estimation of Physical Climate Risk for Private Companies)

  • 최용상;유창현;공민정;조민정;정해수;이윤경;박선기;안명환;황재학;김성주
    • 대기
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    • 제34권1호
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    • pp.1-21
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    • 2024
  • Private companies are increasingly required to take more substantial actions on climate change. This study introduces the principle and cases of climate (physical) risk estimation for 11 private companies in Korea. Climate risk is defined as the product of three major determinants: hazard, exposure, and vulnerability. Hazard is the intensity or frequency of weather phenomena that can cause disasters. Vulnerability can be reflected in the function that explains the relationship between past weather records and loss records. The final climate risk is calculated by multiplying the function by the exposure, which is defined as the area or value of the target area exposed to the climate. Future climate risk is estimated by applying future exposure to estimated future hazard using climate model scenarios or statistical trends based on weather data. The estimated climate risks are developed into three types according to the demand of private companies: i) climate risk for financial portfolio management, ii) climate risk for port logistics management, iii) climate risk for supply chain management. We hope that this study will contribute to the establishment of the climate risk management system in the Korean industrial sector as a whole.

포아송 및 음이항 회귀분석을 이용한 해상운임 결정요인이 해운선사의 블랭크 세일링에 미치는 영향 분석 연구 (A Study on Impact of Factors Influencing Maritime Freight Rates Using Poisson and Negative Binomial Regression Analysis on Blank Sailings of Shipping Companies)

  • 류원형;남형식
    • 한국항해항만학회지
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    • 제48권1호
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    • pp.62-77
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    • 2024
  • 해상운송 산업에서는 공급과 수요의 불균형이 지속적으로 증가하면서 세계 주요 해운선사들이 해운 시황에 따른 선복량을 탄력적으로 조절하기 위해 블랭크 세일링을 주요 수단으로 사용하고 있다. 일반적으로 블랭크 세일링은 중국의 춘절 기간에 맞추어 많이 실시되어 왔지만, 2020년부터 시작된 글로벌 팬데믹과 미국·중국 간 무역 전쟁 등과 같은 특수한 상황으로 인해 최근 해운선사들은 기존 대비 큰 규모의 블랭크 세일링을 실시하였다. 이러한 블랭크 세일링은 화물 운송 지연에 직접적 영향을 미치기 때문에 기업과 소비자의 측면에서 부정적인 영향을 초래할 수 있다. 따라서 본 연구는 이에 선제적으로 대응하기 위해 포아송 회귀모형과 음이항 회귀모형을 활용하여 해상운임 결정요인이 해운선사의 블랭크 세일링에 미치는 영향력을 분석하였다. 분석 결과, 포아송 회귀분석의 2M의 경우 유의한 변수로 글로벌 컨테이너 해상물동량, 컨테이너 선복량, 컨테이너선 해체량, 컨테이너선 신조선가지수, OECD 인플레이션을 도출하였고, 음이항 회귀분석의 Ocean Alliance의 경우 글로벌 컨테이너 해상물동량과 컨테이너선 발주량을, THE Alliance의 경우 컨테이너선 선복량과 금리를, Non-Alliance의 경우 국제유가, 글로벌 공급망 압력지수, 컨테이너선 선복량, OECD 인플레이션을, Total Alliance의 경우 컨테이너선 선복량과 금리를 유의한 변수로 도출할 수 있었다.

Directions towards sustainable agricultural systems in Korea

  • Kim, Chang-Gil
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.3-3
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    • 2017
  • The question of how to establish sustainable agricultural systems has become as prominent as questions related to water, energy and climate change. High input/high output agriculture has brought with it many adverse effects; the massive deterioration of soil and water in both quantity and quality, increased greenhouse gas emissions and an increased prevalence of unsafe foods. Additionally, urbanization and climate change has worsened the shortage of farmland and reduced the supply of agricultural water. Given these challenges, maintaining, conserving and efficiently using agri-environmental resources, through fostering of sustainable agriculture, have emerged as key tasks in solving these problems. What is needed therefore is research, based on systematic and comprehensive empirical analyses, that can propose plans and methods for establishing an appropriate sustainable agricultural system. The empirical analysis of sustainable agricultural system is approached separately from economic, environmental and social aspects. An analysis of environment effect reveals that the available phosphate level is 1.3~2.1 times greater than the optimal amount in rice paddies, upland fields and orchards. Further examination has revealed that the excess nutrient is polluting both ground water and surface water. Analytical results for economic feasibility show that factors of production have been invested heavily in the rice crop. Under these conditions, sustainable agriculture, including low-input agriculture, appears to be a possible alternative that will facilitate simultaneous improvements in both economic feasibility and environment effects. Analysis results for sociality reveal that social factors include the value of producer, association and interior networks. Social conditions are comprised of leadership, consumers' awareness, education and conflict solutions. In addition, analysis as to the degree investments contribute to improving agricultural value added has revealed that the direct payment program is the most effective instrument. Experts confirm that economic feasibility can be improved by scientific and well-reasoned nutrient management on the basis of soil testing. Farmers pointed to 'economic factors' as being the largest obstacle to switching to the practice of sustainable agriculture. They also indicate 'uncertainty with regards to sustainable agriculture technology' as an impediment to practicing sustainable agriculture. Even so, farmers who believe environmental and regional issues to be the most pressing problems have expanded their practice of sustainable agriculture. The keys to establishing sustainable agriculture system are classified into the following four aspects. Firstly, from an economic aspect, the research indicates that agricultural policy needs to be integrated with environmental policy and that the function of market making based on the value chain needs to be revitalized. Secondly, from an environmental aspect, there is a need for an optimal resource management system to be established in the agricultural sector. In addition, sustainable agriculture practice will need to be extended with attendant environmentally-friendly and sustainable intensive technology also requiring further development. Thirdly, from a social aspect, green agriculture management needs to be fostered, technology and education extended, and social conflict mediated. Lastly, from a governance aspect, it will be necessary to strengthen good governance, assign and share suitable roles and responsibilities, build a cooperation system and utilize community supported agriculture.

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인터모달 추진 정책과 효과에 관한 비교연구 (Comparative Study of the Effects of the Intermodal Freight Transport Policies)

  • 우정욱
    • 유통과학연구
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    • 제13권10호
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    • pp.123-133
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    • 2015
  • Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.