• International Journal of Computer Science & Network Security
• /
• 제22권12호
• /
• pp.37-50
• /
• 2022

Modern supply chains include multiple activities from collecting raw materials to transferring final products. These activities involve many parties who share a huge amount of valuable data, which makes managing supply chain systems a challenging task. Current supply chain management (SCM) systems adopt digital technologies such as the Internet of Things (IoT) and blockchain for optimization purposes. Although these technologies can significantly enhance SCM systems, they have their own limitations that directly affect SCM systems. Security, performance, and scalability are essential components of SCM systems. Yet, confidentiality and scalability are one of blockchain's main limitations. Moreover, IoT devices are lightweight and have limited power and storage. These limitations should be considered when developing blockchain-based IoT-SCM systems. In this paper, the requirements of efficient supply chain systems are analyzed and the role of both IoT and blockchain technologies in providing each requirement are discussed. The limitations of blockchain and the challenges of IoT integration are investigated. The limitations of current literature in the same field are identified, and a secure and scalable blockchain-based IoT-SCM system is proposed. The proposed solution employs a Hyperledger fabric blockchain platform and tackles confidentiality by implementing private data collection to achieve confidentiality without decreasing performance. Moreover, the proposed framework integrates IoT data to stream live data without consuming its limited resources and implements a dualstorge model to support supply chain scalability. The proposed framework is evaluated in terms of security, throughput, and latency. The results demonstrate that the proposed framework maintains confidentiality, integrity, and availability of on-chain and off-chain supply chain data. It achieved better performance through 31.2% and 18% increases in read operation throughput and write operation throughput, respectively. Furthermore, it decreased the write operation latency by 83.3%.

• 대한안전경영과학회지
• /
• 제8권3호
• /
• pp.159-170
• /
• 2006

This paper deals with the S/W development of web-based warehouse management system using ubiquitous RFID(Radio Frequency Identification). This S/W System supports the realtime inventory management and collaborative operations of relational companies in SCM. We expect to decrease the logistic cost and to upgrade the status of WMS and competitive power of company.

• 한국항만경제학회지
• /
• 제30권4호
• /
• pp.47-67
• /
• 2014

본 연구에서는 시스템적 관점과 공급사슬 구성원들 간의 상호작용을 통한 전략적 관점에서 컨테이너터미널의 물류시스템을 평가하기 위해 공급사슬관리 개념을 적용하였다. 선행연구와 델파이 기법을 이용하여 컨테이너터미널 물류시스템의 SCM 구성요인으로 유연성, 신뢰성, 대응성, 정보공유성을 도출하였고, 세부평가 항목으로 16개 항목을 선정하였다. 컨테이너터미널 물류시스템 구성요인에 대한 평가 결과를 보면, 신뢰성 요인이 0.282으로 가장 높았고, 유연성 요인이 0.273, 대응성 요인이 0.224, 정보공유성 요인이 0.221 순으로 나타났다. 컨테이너터미널 물류시스템의 SCM 구성요소 가중치와 세부평가항목의 가중치를 결합하여 환산 가중치를 산출한 결과를 보면, 유연성 구성요소의 세부항목인 작업 Planning(선석, 야드) 항목의 가중치가 0.081로 컨테이너 터미널의 물류시스템을 평가하는 가장 중요한 요인으로 나타났고, 컨테이너 작업 스케줄의 정확한 이행(선박, 야드) 항목과 장비 적정배분 및 배치(QC, TC, YT)항목이 0.079, 컨테이너 및 선박의 손상 없는 안정적인 작업 항목이 0.071 그리고 장비운전자 숙련도 및 장비예방 정비 항목이 0.070 순으로 분석되었다. 다음으로 양 적하 및 선적정보 항목이 0.064, 작업 모니터링과 오류에 대한 해결 항목이 0.062, 대형선박 작업 가능성 항목이 0.060, 신속한 게이트 반 출입 시스템 항목과 무료 장치기간 제공 항목이 0.057, 내륙운송 연계서비스 항목이 0.055, 컨테이너 작업정보 항목이 0.053, 마지막으로 반 출입 정보 항목과 컨테이너 이력 및 장치정보 항목 그리고 컨테이너(일반, 특수)관리 및 서비스 항목이 0.052 순으로 나타났다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제10권3호
• /
• pp.1404-1415
• /
• 2016

Because of the properties of software such as invisibility, complexity, and changeability, software configuration management (SCM) for software artifacts generated during software life-cycle has been used for guarantee of the quality of the software. However, the existing SCM system has only focused on code artifacts and software development document artifacts such as Software Requirements Specification (SRS), Software Design Description (SDD), and Software Test Description (STD). Moreover, software research-oriented project comes out late the code artifacts and the software development document artifacts. Therefore, there is a need for trace and management of software research document artifacts composed of highly abstracted non-functional requirements like 'the purpose of the project', 'the objectives', and 'the progress' before generation of the code artifacts and the software development document artifacts for a long time. Nevertheless, the existing SCM system cannot trace and manage them. In this paper, we propose content-based configuration management system comprised of the relevance link generation phase and content-based testing phase to trace and manage them. The preliminary application results show applicability and feasibility of the proposed system.

• 한국통신학회논문지
• /
• 제34권5C호
• /
• pp.527-539
• /
• 2009

본 논문에서는 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) MIMO-OFDMA(multiple-input multiple-output-orthogonal frequency division multiple access) 시스템의 하향 링크 수신기를 위한 asynchronous ICI (Inter-Cell Interference) 완화 기법을 제안한다. Multi-cell 환경을 고려한 celluar OFDMA 시스템에서는 기본적으로 frequency reuse factor가 1로 설정되기 때문에 셀 경계에 위치한 UE (User Equipment)의 경우 ICI 영향을 받게 되며, 특히 각기 다른 셀 반경 및 nodeB 간의 거리 차이 등 현실적인 celluar 환경을 고려 할 경우에는 UE 간 타이밍 오류가 가중되어 수신 신호의 주파수 영역의 직교성이 파괴될 가능성이 있다. 따라서 이러한 인접 셀 간섭을 제거 및 완화하기 위하여 수신 OFDM 심볼에 대한 SCM (Spatial Covariance Matrix) 추정이 필요하다. 일반적으로 SCM 추정은 training symbol을 이용함을 가정하지만, 긴 시간 동안 간섭의 통계적 특성을 측정하는 것은 어려울 뿐만 아니라 training symbol이 고려되지 않는 LTE와 같은 MIMO-OFDMA 시스템에는 적합하지 않다. 또한 추정의 정확성을 높이기 위하여 noise reduction 방식이 적용된 추정 기법이 제시되고 있으나, 기존 time-domain low-pass type weighting 방식은 spectral leakage에 의한 추정 에러를 유발하는 단점이 있다. 따라서, 본 논문에서는 noise reduction 효과를 얻으면서 spectral leakage에 의한 SCM 추정 오류를 최소화할 수 있으며, 주파수 영역에의 moving average filter로 구현 가능한 time-domain sinc-type weighting 방식의 SCM 추정 기법을 제안하였으며, 다양한 환경에서의 컴퓨터 모의 실험을 통하여 제안된 방식이 기존의 방식보다 약 3dB 의 SIR (Signal to Interference Ratio) 이득을 보임을 입증하였다.

• 한국CDE학회논문집
• /
• 제21권3호
• /
• pp.353-362
• /
• 2016

As ships become larger and construction of offshore plants increases recently, the amount of outsourcing has increased accordingly in the shipyard. Consequently, the system integration in terms of SCM (Supply Chain Management) of information and material flows has become much more important. Especially, since the SCM in the shipbuilding industry is operated in accordance with the production planning in connection with design, purchasing and production process which are the main components of the supply chain, the best production plan has to be established over the whole scheduling activities from the long-term planning to the short-term planning. The paper analyzes the characteristics of the SCM and the production planning system and suggests the need and the direction of APS (Advanced Planning System) development specialized in the supply chain management only for shipbuilding industry. Furthermore, propose a new SCP-Matrix (Supply Chain Planning Matrix), which is the basis of the APS development, appropriate for the shipbuilding industry and draw the core function of the APS module for the practical production plan.

• 융합정보논문지
• /
• 제9권9호
• /
• pp.13-19
• /
• 2019

본 논문은 미국 정부가 추진하고 있는 커넥티드 차량에서 SCMS와 파일롯 정책에 대해 분석하였다. SCMS는 인증, 무결성, 프라이버시, 그리고 상호운용성을 보장한다. 미국의 SCMS 지원위원회는 국가단위의 SCMS를 설립하고 시스템 전반에 대한 통제 역할을 수행하고 있다. 물론 보안 정책 수립 그리고 절차와 훈련 프로그램을 도입한다. 본 논문에서는 C-ITS에 적용하는 SCMS의 필요성에 대해 논의하였다. 그리고 SCMS의 구조에 대해 분석하였고 미국 정부의 커넥티드 차량의 파일롯 정책에 대해 고찰하였다. SCMS의 필요성에 대한 논의에서 차량과 차량 사이에 SCMS의 역할과 책임성이 중요하다는 사실을 강조하였다. 보안 인증 관리시스템에서는 구조를 살펴보았는데 차량이나 RSU에 사용되는 인증서의 유형에 대해 분석하였다. 인증서에 따른 기능과 특성을 분석하였다. 또한 SCMS가 가지는 비정상 행위에 대한 탐지와 경고 기능에 대한 고찰과 함께 기본 안전성 메시지의 기능에 대해서 분석하였다. 마지막으로 현재 미국 정부가 추진하고 있는 커넥티드 차량의 파일롯 프로젝트의 현황을 분석하였다. 테스트에 사용되는 환경과 함께 관련 메시지에 대해서도 분석하였다. 파일롯 프로젝트를 추진함에 있어서 발생하는 논의점에 대해서도 살펴보았다.

• Journal of Magnetics
• /
• 제21권3호
• /
• pp.330-339
• /
• 2016

A magnetic field sensing system with a single primary sensor and multiple reference sensors deployed locally and orthogonally, was proposed for downlink signal reception and interference cancelling for Through-the-Earth Communication (TEC). This paper mathematically analyzes a design optimization process for a search coil magnetometer (SCM), and applies that process to minimize the bandwidth of the primary SCM for TEC signal reception and the volume of reference SCMs for multiple distributions. The primary SCM achieves a 3-dB bandwidth of 7 Hz, a sensitivity threshold of 120 fT/${\surd}$Hz, and a volume of $2.32{\times}10^{-4}m^3$. The entire sensing system volume is as small as $10^{-2}m^3$. Experiments with interference from industrial frequency harmonics demonstrated an average of 36 dB and 18 dB improvements in signal-to-interference ratio and signal-to-interference plus noise ratio, respectively, using multichannel recursive-least-squares algorithm. Thus, the proposed sensing system can reduce the interference effectively and allows reliable downlink signal reception.

• Journal of the Optical Society of Korea
• /
• 제16권4호
• /
• pp.449-456
• /
• 2012

For two well-known modulation methods, stepwise current modulation (SCM) and pulse width modulation (PWM), the effects of driving current modulation conditions on chromaticity were experimentally investigated in a white LED lighting system. For the experimental implementation of both SCM and PWM, a white LED lighting was fabricated using phosphor converted (PC) white light emitting diodes (LEDs) and a driving circuit module was developed. By using them, the variations of illuminance, color coordinates, and spectrum were evaluated under various forward current conditions. Through the analysis in color coordinates, yellow shift in SCM and blue shift in PWM were observed on chromaticity diagrams with increasing average driving current. In addition, in order to analyze color deviation quantitatively, color distance before and after current increase, and the correlated color temperature (CCT) were calculated. As a result, for the white LED lighting in both modulation conditions, the maximum difference in the calculated CCT was obtained close to 1000 K. It means that careful consideration is required to be taken in the design of illumination systems to avoid serious problems such industrial accidents.

• 무역상무연구
• /
• 제36권
• /
• pp.143-170
• /
• 2007

In order to analyze the distribution channel of marine products in Korea, this study shows SCM approach to redesign of the marine distribution channel with case study related to previous literatures. In view of the supply chain and the future impact of RFID on the marine SCM on the recognition of the importance of the seafood traceability system, this study also provides the possibility to accomplish effective SCM for integration of production, storage, transportation, delivery, and sale when RFID is used in the seafood distribution channel based on the expansion of awareness on the marine product traceability. The traceability system for seafood is considered as the distribution infrastructure established in RFID deployment. By introducing Lotte mart case, this case study also discusses the marine distribution structure in view of the supply chain, to present an effective foundation for supplying seafood throughout production, distribution, and consumption. This is achieved by introducing RFID in an ubiquitous environment, and suggesting far more efficient control planning throughout the seafood distribution channel in view of the expected effects resulting from the introduction. In addition, as the alternative of solving this situation, this study propose the supply chain in seafoods by comprehensive management in whole distribution channels. In the SCM in seafood perspectives, HACCP can take into account the whole seafood chain from the point of supply to the point of consumption when assessing hazards. As the contributions of this study, this study emphasizes the seafood industry first should require the establishment of the relevant infrastructure, for which the efforts of the government and demonstrative project participants are essential.