• 한국빅데이터학회지
• /
• 제4권2호
• /
• pp.159-173
• /
• 2019

말단배송최적화는 도심내 공급사슬의 운영의 핵심적인 역할을 수행하고 있으며, 전체 배송 프로세스에서 가장 복잡하고 많은 비용을 지불해야만 한다. 도심복합물류센터 (Urban Consolidation Center: UCC)는 최근 말단배송 서비스를 운영하고 고객의 수요를 만족시키기 위한 핵심적인 자산으로 인식되고 있다. UCC를 활용할 경우 도심 내 다양한 요인을 고려하여 최적의 배송 과정을 설계함으로써 배송에 소요되는 시간과 이동거리를 최소화할 수 있다는 장점이 존재한다. 본 연구에서는 지리정보시스템 (GIS)를 활용하여 다양한 수리모형이 통합된 시나리오 분석을 활용하기 위한 기법을 제안한다. 특히, 본 연구는 몽골의 수도 울란바타르를 사례로 실제 도심 내 최적 배송네트워크를 설계하는 것을 목표로하고 있다. 이를 위해 위치배분문제와 차량경로문제를 결합하는 기법을 제안하였다. UCC의 위치와 개수를 기반으로 다양한 시나리오를 설계하였으며, 기본적인 총배송거리, 배송시간, UCC의 수 및 필요 차량의 수를 기준으로 시나리오를 평가하였다. 또한, UCC의 건설과 운영에 필요한 전체 비용 관점에서 최적의 시나리오를 비교 선정하였다. 본 연구의 결과는 도심 내 말단 배송을 위한 유통 네트워크를 설계해야 하는 관리자 혹은 정부 기관의 담당자들이 합리적인 의사결정을 내리기 위한 객관적인 근거 자료로 활용될 수 있을 것이다.

• 유통과학연구
• /
• 제12권2호
• /
• pp.95-103
• /
• 2014

Purpose - Korea has a better geographical location than other nations in the Northeast Asian region. This means that Korea has an opportunity to become the center of international physical distribution in Northeast Asia. Korea should take advantage of this opportunity by exploring appropriate strategies to achieve this goal, assuming government willingness, with a view to capitalizing on the geographical advantage of the Korean peninsula and constructing a comprehensive physical distribution network system. If we prepare for this scenario, Korea could become the center of international physical distribution in Northeast Asia. Research design, data, and methodology - This study has the purpose of determining how shipping companies form partnerships with third-party logistics providers, and the relevant implications. The survey methods used were personal interview and a questionnaire distributed through e-mail, fax, mail, and telephone. A total of 600 questionnaires were distributed, out of which 285 were returned. Of the collected questionnaires, 10 were excluded because of insufficient content, leaving 275 to be used in the study as available valid samples. The data that was collected from these samples was analyzed using the data coating process and by employing a statistical package program. Results - Flexible policies, administration, and systems will be needed to create better business practices. In this dissertation, first and foremost, the results reveal that in order to become the center of Northeast Asian logistics, Korea must transition into a new paradigm based on the current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. Flexible policies, administration, and systems will be required to create better business practices. Domestic logistics corporations need to occupy a strategic logistics hub, create a logistics network, and activate value-added logistics business strategies by ensuring significant manpower and by building a logistics information system to strengthen their competitive edge, creating an improved system. Conclusions - In this dissertation, first and foremost, we point out that in order to become a center of North East Logistics, Korea should change to a new paradigm from the old one based on current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. More reasonable business laws, systems, and policies based on market-driven flexibility and transparency should be created. Moreover, social norms and rules should be reasonably established, to accomplish political and social security. Korea has to cultivate a culture of tolerance for foreign companies. This involves a change of paradigm for the development of the capital city and satellite cities. It will take a powerful task force or organization to plan and execute the vision that aims to meet these needs, accomplish the necessary goals, use the appropriate system effectively, and make Korea a key country in the field of Northeast Asian logistics.

• 한국정보보호학회:학술대회논문집
• /
• 한국정보보호학회 2006년도 하계학술대회
• /
• pp.599-603
• /
• 2006

유비쿼터스 센서 네트워크(Ubiquitous Sensor Network, USN)는 차세대 네트워크로 각광받고 있고 이러한 센서 네트워크의 보안에 대한 관심은 더욱 높아지고 있다. 왜냐하면 센서 네트워크를 외부 공격자로부터 보호하기 위해서는 센서 노드 사이의 암호화 통신과 인증 등이 필요하기 때문이다. 이를 위해서는 안전한 키 생성 및 폐기가 우선 이루어져야 한다. 지금까지 센서 네트워크를 위해 제안된 키 분배 프로토콜은 매우 다양하다. 그러나 이러한 프로토콜들이 기반하고 있는 가정들이 얼마나 안전하고 현실성 있는 지 분석되어 있지 않다. 키 분배의 대표적 프로토콜인 LEAP(Localized Encryption and Authentication Protocol)은 무선 센서 네트워크에 적합한 가정을 하였다고 알려져 있다. 본 논문에서는 이 LEAP 프로토콜을 USN 상에서 구현을 통해 이 가정의 현실성에 대해 분석해 볼 것이다. 이는 차후 다양한 키 분배 프로토콜을 연구 개발하는 데 있어서 상당한 도움이 될 거라 예상된다.

• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2007년도 학술대회
• /
• pp.371-375
• /
• 2007

In this paper, we have implemented the device management system to upgrade T-PAK software in mobile phone. The hybrid scheduling method and selective upgrade method are proposed. Hybrid scheduling method is based on distribution of delivery data in accordance with network traffic load and service priority from device management server to mobile phone. Selective upgrade method manages DSL classified by T-PAK software version to be upgrade using version management established in OMA DM SCOMO. Key mechanism of selective upgrade method is to only deliver DSL to be replaced to the mobile phone. We made an experiment on two methods using MS-700T terminals. The experimental result shows that the proposed method is faster than normal from delivery time standpoint.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
• /
• pp.1540-1541
• /
• 2006

For limitation and interruption of short circuit currents from low voltage to extra high voltage applications, the electrical equipment including fuses and circuit breakers, are widely used today. But in order to anticipate increasing needs for effective and competitive device for limiting the growing fault current in electrical power systems, fault current limitation technologies and fault current limitation devices are widely introduced and investigated in these days. Fault current limiters are emerging electric equipment which is under development using various methods including superconducting fault current limiter, solid state fault current limiter, arc driving fault current limiters. And these various methods have some advantages and disadvantages to take into considerations In order to commercialize fault current limiters in the electrical networks, a lot of discussions should be given on the point that fault current limiting methods, need for fault current limiters, coordination with existing protective system, and field experience before commercialization. In this paper, recent trends of fault current limiting technologies will be reviewed and the key issues of superconducting fault current limiters will be dealt with. And finally, future applications of superconducting fault current limiters would be discussed.

• 유통과학연구
• /
• 제17권3호
• /
• pp.41-47
• /
• 2019

Purpose - Based on the analysis of Kazakhstan's experience of digital transformation, this study suggests a concept for digital solution to optimize organizational process, create trust networking between the center of state scholarships programs and recipients. In addition, the authors contribute to the current discussions of an effective digital transformation of state services. Research design, data, and methodology - Policy analysis is based on the combination of both primary and secondary materials collected during a Policy Research Project conducted in Kazakhstan in 2017. It involved semi-structured interviews with the state scholarship' recipients, ICT experts and findings from academic articles. Results - Findings are represented via Policy Development Matrix - a table with three options (status quo, partial change, total change) to deal with policy challenges. Authors suggest a concept for digital solution following the Customer Relationship Management (CRM) principles for optimizing core business processes, communication and networking strategies of the state scholarships program. Conclusions - At the time when digitalization becomes trending for states, the transformation of the state education policy is inevitable. The rapid development of digital technologies creates new opportunities for a single integration platform with key principles of Smart Remote Management in the state scholarships programs.

• Journal of Electrical Engineering and Technology
• /
• 제7권2호
• /
• pp.141-150
• /
• 2012

The present study examines an efficient congestion management system compatible with the evolving environment. The key is to build an information model shared and exchanged for marketbased solutions to alleviate congestion. Traditional methods for congestion management can be classified into two categories, i.e., the centralized scheme and the decentralized scheme, depending on the extent to which the independent system operator (ISO) is involved in market participants' (MPs) activities. Although the centralized scheme is more appropriate for providing reliable system operation and relieving congestion in near real-time, the decentralized scheme is preferred for supporting efficient market operation. The minimum set of information between the ISO and MPs for decentralized scheme is identified: i) congestion-based zone, ii) Power Transfer Distribution Factors, and iii) transmission congestion cost. The mathematical modeling of the proposed information is expressed, considering its process of making effective use of information. Numerical analysis is conducted to demonstrate both cost minimization from the MP perspective and the reliability enhancement from the ISO perspective based on the proposed information exchange scheme.

• 디지털산업정보학회논문지
• /
• 제11권3호
• /
• pp.125-143
• /
• 2015

As improving the life quality of citizen because of development of Urbanization and Information, civil application service of public institutions has been changed. The government provides a 24-hour civil service of e-government, public institutions operate U-complaints call center to pursue a personalized service to customers. As customer service are diversified, the inconvenience of service is increased. Therefore, public institutions instituted U-complaints call center to solve increased complaints. In early days, public institutions operated simple call center. However, it became intelligent U-complaints call center by SNS. The more increase the importance of agents' contact customer service, the more increase Job Performance considered by Organizational Commitment & Job Satisfaction of call center agents. This study analyzed that applied to Fairness Theory with Organizational Commitment, Job Satisfaction and analyze U-complaints call center agents' role and job performance of public institutions. Proposed a research model applied to job satisfaction with key variables, organizational commitments, job satisfaction. It's expected to impact on job performance of U-complaints call center agents in public institutions. For empirical study of research model, conducted a survey of the U-complaints call center agents of public institutions. 170 samples were collected from the survey and analyze relationship between the factors. Procedural justice, distribution fairness, fairness interaction are significant influence on organizational commitment of parameters by analysis U-complaints call center agents. Procedural justice and fairness of interaction was found not to effect on parameters of job satisfaction. Also, parameter, organizational commitment have significant influence on job satisfaction. However, have no influence on job performance. Therefore, the parameters of job satisfaction have significant influence on job performance. Public institutions should adopt to improve the quality of citizen services through U-complaints call center agents.

• 대한전자공학회논문지TC
• /
• 제43권7호
• /
• pp.32-40
• /
• 2006

무선 센서 네트워크에서 두 노드사이에 안전하게 pairwise키를 설정하고 분배하는 것은 매우 중요한 문제이다. 센서 네트워크는 물리적으로 취약한 보안성을 갖는 노드로 구성되므로 공격자에 의해 오염되기 쉽다. 그러나 기존의 선행 키 분배를 이용한 pairwise 키설정이나 1홉 지역키를 이용한 pairwise키 설정은 작은수의 노드들이 오염되더라도 보안성을 크게 약화시킨다. 본 논문은 무선 센서 네트워크에서 각 노드들이 네트워크 구성 초기에 3홉 지역키를 설정하고, 이후의 pairwise 키 설정에 이들 3홉 지역키들을 이용하는 방법을 제안한다. 임의의 두 노드가 pairwise 키를 설정할 때, 두 노드 사이의 경로상에 존재하는 노드들은 자신들의 비밀키들을 두 노드에게 전송하는것에 의해 pairwise키의 생성에 공헌한다. 이로인해, 제안방법은 노드 밀집도와는 상관없이 두 노드사이의 경로길이에 의해 키설정을 위한 전송메시지수가 결정된다. 이때 경로상의 노드들로부터의 비밀 키들을 안전하게 다른 노드들에게 전달하기 위해 3홉 지역키들이 비밀키들의 암호화에 사용된다. 따라서, 제안방법은 공격자가 1홉 지역키를 이용하는 방법에 비해 보다 많은 노드들을 오염시키도록 괴롭힌다. 실험결과는 제안된 방안이 선행 키 분배 방법에 비해 단위 키설정 동안 교환되는 메시지수 와 암호화/복호화 연산횟수, 그리고 안전성 면에서 보다 우수함을 입증하였다.

• Wind and Structures
• /
• 제31권3호
• /
• pp.269-285
• /
• 2020

The statistical characteristics of typhoon wind speed records tend to have a considerable time-varying trend; thus, the stationary wind model may not be appropriate to estimate the wind characteristics of typhoon events. Several nonstationary wind speed models have been proposed by pioneers to characterize wind characteristics more accurately, but comparative studies on the applicability of the different wind models are still lacking. In this study, three landfall typhoons, Ampil, Jongdari, and Rumbia, recorded by ultrasonic anemometers atop the Shanghai World Financial Center (SWFC), are used for the comparative analysis of stationary and nonstationary wind characteristics. The time-varying mean is extracted with the discrete wavelet transform (DWT) method, and the time-varying standard deviation is calculated by the autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model. After extracting the time-varying trend, the longitudinal wind characteristics, e.g., the probability distribution, power spectral density (PSD), turbulence integral scale, turbulence intensity, gust factor, and peak factor, are comparatively analyzed based on the stationary wind speed model, time-varying mean wind speed model and time-varying standard deviation wind speed model. The comparative analysis of the different wind models emphasizes the significance of the nonstationary considerations in typhoon events. The time-varying standard deviation model can better identify the similarities among the different typhoons and appropriately describe the nonstationary wind characteristics of the typhoons.