• 대한산업공학회지
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• 제25권1호
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• pp.87-99
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• 1999

A shop floor control system(SFCS) performs the production activities required to fill orders. In order to effectively control these activities, the autonomous agent-based heterarchical shop floor control architecture is adopted where a supervisor does not exist. In this paper, we define functional perspective of the heterarchical shop floor control using planning, scheduling, and execution modules. In particular, we focus on an execution module that can coordinate the planning and scheduling modules and a general execution module that easily can be modified to execute the other equipment. The execution module can be defined informally as a module that downloads and performs a set of scheduled tasks. The execution module is also responsible for identifying and resolving various errors whether they come from hardware or software. The purpose of this research is to identify all the execution activities and solving techniques under the assumptions of the heterarchical control architecture. And we model the execution module in object-oriented modelling technique for generalization. The execution module modeled in object-oriented concept can be adopted to the other execution module easily. This paper also proposes a classification scheme for execution activities of the heterarchical control architecture. Petri-nets are used as a unified framework for modeling and controlling execution activities. For solving the nonexistence of a supervisor, a negotiation-based solution technique is utilized.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.800-807
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• 2003

Decomposition of tasks in the ordinary manufacturing systems is usually based on the predefined goal of the system. To achieve the high-level-goals (e.g., factory goal or company goal), several sub-goals should be achieved in advance. However, goals can change along with the current status of the system and the external environmental situations. Thus, a manufacturing system should support the goal-formations which can be bearable these changes for efficient and effective operations. Therefore, it IS necessary to develop a systematic methodology for the goal-formations in a manufacturing system. Especially, the formation and/or change of goals in real-time should be possible for distributed and dynamic systems including the fractal manufacturing system (FrMS). In this paper, a threefold methodology is proposed for the goal-formation process (GFP) in the FrMS; 1) a goal­generating process (GGP) to make and propagate fuzzy goals, 2) a goal-harmonizing process (GHP) to eliminate or reduce conflicts and interferences of goals by using a mobile agent- based negotiation scheme, and 3) a goal-balancing process (GBP) to make a compromise between goals by using quantifiable indicators of the manufacturing system.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.85-90
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• 2002

최근 건설 프로젝트가 대형화 및 복잡화됨에 따라 다수의 하도급업체들이 참여하는 형태로 진행되고 있다. 특히 하도급업체들이 자체 자원을 운용하여 공사를 수행함에 따라, 기존의 원 도급업체가 주도하는 중앙집중식 조정방식은 실효성이 저하되고 있다. 하도급업체의 자원수급이 건설공사의 공정과 일치하지 않을 경우 해당업체의 공사가 지연될 뿐만 아니라, 다른 하도급업체의 공사들과 더 나아가 건설공사의 지연을 초래한다. 이에 따라, 관련 하도급업체들이 해당 공사에 공정변경이 생길 경우에 이에 맞추어 건설공사 공정을 조정하는 새로운 건설공사 공정변경의 분산조정에 관한 연구가 필요하다. 연구자는 건설공사 공정변경의 분산조정방식 및 이를 위한 소프트웨어 에이전트를 이용한 보상협의 방법을 정의하였다. 본 연구는 현재의 건설공사 주체인 하도급업체의 자원수급의 효율성을 향상시키는 데 필요한 방법을 정의하고, 구현하고, 검증함으로서 하도급업체의 이윤추구 및 건설공사의 성공적인 수행을 함께 달성할 수 있도록 한다.

• 만화애니메이션 연구
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• 통권36호
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• pp.121-145
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• 2014

조합원의 이익 극대화를 목적으로 조합원들에 의해 민주적으로 운영되는 협동조합은 다양한 사회경제적 요구에 부응할 수 있는 새로운 사업모델로 주목받고 있다. 우리나라에서도 2012년 12월 협동조합기본법이 제정됨에 따라 전 산업에 걸쳐 다양한 종류의 협동조합 설립이 가능하게 되었다. 본 연구는 해외시장 진출을 위한 노력과 성과에도 불구하고, 실질적인 해외시장 매출은 기대에 미치지 못하고 있는 한국 애니메이션의 해외배급 개선방안 모색을 위해, 애니메이션 제작사들이 조합원으로 참여하는 해외 마케팅협동조합의 도입 타당성과 기대효과를 논의하였다. 애니메이션 제작사들과의 인터뷰 결과, 한국 애니메이션 해외 배급의 문제는, 1)취약한 마케팅 조직과 전문성, 2)TV 방영권 위주의 판매로 인한 부가판권 매출 미흡, 3)지역별로 특화된 마케팅 역량의 부족으로 확인되었고, 이는 수익성과 자금력이 취약한 애니메이션 제작사들로서는 해결하기 어려운 과제이다. 해외 마케팅협동조합이 설립된다면, 애니메이션 제작사들로서는 불가능했던 심층적인 시장조사 등을 통해 해외시장 적응력이 강화되고. 조합원들이 제작한 여러 작품을 함께 판매함에 따라, 장르 물량 타겟 등과 관련한 해외 거래선의 다양한 수요에 대한 대응력 및 협상력 강화를 기대할 수 있다. 또한, 조합원들의 자본과 인력을 함께 투입함으로써, 적극적인 홍보 마케팅을 통해 작품의 브랜드 가치 제고가 가능하고, TV 방영, 캐릭터 머천다이징, 디지털 미디어 유통 등 가치사슬의 전 과정에 걸친 매출 극대화와 지역별로 특화된 마케팅 조직의 구축이 가능해진다. 무엇보다도, 협동조합을 통해서 조합원들이 모든 주요 의사결정에 평등하게 참여함으로써 각각의 작품을 위한 최적의 마케팅 활동이 수행되도록 관리 통제할 수 있고, 판매 이익은 조합원 인 제작사에게 귀속되기 때문에, 배급사 이익의 극대화를 위해 개별 작품에 최적의 서비스가 제공되지 못하는 '주인-대리인 문제(principal-agent problem)'를 최소화 시킬 수 있다는 점에서 마케팅 협동조합은 효과적인 해외배급 활성화 방안이 될 수 있다.

• Asia pacific journal of information systems
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• 제18권1호
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• pp.145-162
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• 2008

One of the big concerns in e-society is privacy issue. In special, in developing robust ubiquitous smart space and corresponding services, user profile and preference are collected by the service providers. Privacy issue would be more critical in context-aware services simply because most of the context data themselves are private information: user's current location, current schedule, friends nearby and even her/his health data. To realize the potential of ubiquitous smart space, the systems embedded in the space should corporate personal privacy preferences. When the users invoke a set of services, they are asked to allow the service providers or smart space to make use of personal information which is related to privacy concerns. For this reason, the users unhappily provide the personal information or even deny to get served. On the other side, service provider needs personal information as rich as possible with minimal personal information to discern royal and trustworthy customers and those who are not. It would be desirable to enlarge the allowable personal information complying with the service provider's request, whereas minimizing service provider's requiring personal information which is not allowed to be submitted and user's submitting information which is of no value to the service provider. In special, if any personal information required by the service provider is not allowed, service will not be provided to the user. P3P (Platform for Privacy Preferences) has been regarded as one of the promising alternatives to preserve the personal information in the course of electronic transactions. However, P3P mainly focuses on preserving the buyers' personal information. From time to time, the service provider's business data should be protected from the unintended usage from the buyers. Moreover, even though the user's privacy preference could depend on the context happened to the user, legacy P3P does not handle the contextual change of privacy preferences. Hence, the purpose of this paper is to propose a mutual P3P-based negotiation mechanism. To do so, service provider's privacy concern is considered as well as the users'. User's privacy policy on the service provider's information also should be informed to the service providers before the service begins. Second, privacy policy is contextually designed according to the user's current context because the nomadic user's privacy concern structure may be altered contextually. Hence, the methodology includes mutual privacy policy and personalization. Overall framework of the mechanism and new code of ethics is described in section 2. Pervasive platform for mutual P3P considers user type and context field, which involves current activity, location, social context, objects nearby and physical environments. Our mutual P3P includes the privacy preference not only for the buyers but also the sellers, that is, service providers. Negotiation methodology for mutual P3P is proposed in section 3. Based on the fact that privacy concern occurs when there are needs for information access and at the same time those for information hiding. Our mechanism was implemented based on an actual shopping mall to increase the feasibility of the idea proposed in this paper. A shopping service is assumed as a context-aware service, and data groups for the service are enumerated. The privacy policy for each data group is represented as APPEL format. To examine the performance of the example service, in section 4, simulation approach is adopted in this paper. For the simulation, five data elements are considered: $\cdot$ UserID $\cdot$ User preference $\cdot$ Phone number $\cdot$ Home address $\cdot$ Product information $\cdot$ Service profile. For the negotiation, reputation is selected as a strategic value. Then the following cases are compared: $\cdot$ Legacy P3P is considered $\cdot$ Mutual P3P is considered without strategic value $\cdot$ Mutual P3P is considered with strategic value. The simulation results show that mutual P3P outperforms legacy P3P. Moreover, we could conclude that when mutual P3P is considered with strategic value, performance was better than that of mutual P3P is considered without strategic value in terms of service safety.

• 한국정보과학회논문지:정보통신
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• 제34권1호
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• pp.62-72
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• 2007

MVPN(Mobile Virtual Private Network)은 이동단말을 사용하는 이동근무자가 지역적 제한없이 VPN 서비스를 제공받을 수 있도록 하는 기술이다. 이동 VPN 사용자에게 지속적인 VPN 서비스를 제공하기 위해서는 이동성을 제공하기 위한 MIP(Mobile IP) 프로토콜과 IPsec 기반 VPN 기술의 공존이 필요하다. 그런데 MIP와 IPsec 기반 VPN GW(Gateway)를 함께 사용하게 되면 등록 실패나 빈번한 IPsec 터널 재 설립과 같은 문제가 발생한다. IETF에서는 이와 같은 문제를 해결하기 위해 VPN GW의 외부에 홈 에이전트(x-HA)를 사용하는 방안을 제시하였고, 이를 기반으로 동일한 외부네트워크 내에서의 이동에 대한 핸드오버 지연을 줄이기 위한 방안으로 MN(Mobile Node)이 위치한 외부네트워크 내에 x-HA를 동적으로 할당하는 방안도 제안되었다. 그러나 동적으로 x-HA를 할당하는 방안은 세션 키의 노출이나 네트워크 간 이동시의 긴 핸드오버 지연 발생과 같은 문제를 가진다. 이에 본 논문은 이동 VPN 사용자의 핸드오버 지연시간을 최소화하고 핸드오버로 인한 데이타 손실을 줄이면서 보안을 강화하는 새로운 MVPN 프로토콜을 제안하고, 시뮬레이션을 통해 기존에 제안된 방안과 비교하였다.

• 수산경영론집
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• 제34권2호
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• pp.75-90
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• 2003

When we think of fundamental problems of the aquaculture industry, there are several strict conditions, and consequently the aquaculture industry is forced to change. Fish aquaculture has a structural supply surplus in production, aggravation of fishing grounds, stagnant low price due to recent recession, and drastic change of distribution circumstances. It is requested for us to initiate discussion on such issue as “how fish aquaculture establishes its status in the coastal fishery\ulcorner, will fish aquaculture grow in the future\ulcorner, and if so “how it will be restructured\ulcorner” The above issues can be observed in the mariculture of yellow tail, sea scallop and eel. But there have not been studied concerning seabream even though the production is over 30% of the total production of fish aquaculture in resent and it occupied an important status in the fish aquaculture. The objectives of this study is to forecast the future movement of sea bream aquaculture. The first goal of the study is to contribute to managerial and economic studies on the aquaculture industry. The second goal is to identify the factors influencing the competition between production areas and to identify the mechanisms involved. This study will examine the competitive power in individual producing area, its behavior, and its compulsory factors based on case study. Producing areas will be categorized according to following parameters : distance to market and availability of transportation, natural environment, the time of formation of producing areas (leaderㆍfollower), major production items, scale of business and producing areas, degree of organization in production and sales. As a factor in shaping the production area of sea bream aquaculture, natural conditions especially the water temperature is very important. Sea bream shows more active feeding and faster growth in areas located where the water temperature does not go below 13∼14$^{\circ}C$ during the winter. Also fish aquaculture is constrained by the transporting distance. Aquacultured yellowtail is a mass-produced and a mass-distributed item. It is sold a unit of cage and transported by ship. On the other hand, sea bream is sold in small amount in markets and transported by truck; so, the transportation cost is higher than yellow tail. Aquacultured sea bream has different product characteristics due to transport distance. We need to study live fish and fresh fish markets separately. Live fish was the original product form of aquacultured sea bream. Transportation of live fish has more constraints than the transportation of fresh fish. Death rate and distance are highly correlated. In addition, loading capacity of live fish is less than fresh fish. In the case of a 10 ton truck, live fish can only be loaded up to 1.5 tons. But, fresh fish which can be placed in a box can be loaded up to 5 to 6 tons. Because of this characteristics, live fish requires closer location to consumption area than fresh fish. In the consumption markets, the size of fresh fish is mainly 0.8 to 2kg.Live fish usually goes through auction, and quality is graded. Main purchaser comes from many small-sized restaurants, so a relatively small farmer and distributer can sell it. Aquacultured sea bream has been transacted as a fresh fish in GMS ,since 1993 when the price plummeted. Economies of scale works in case of fresh fish. The characteristics of fresh fish is as follows : As a large scale demander, General Merchandise Stores are the main purchasers of sea bream and the size of the fish is around 1.3kg. It mainly goes through negotiation. Aquacultured sea bream has been established as a representative food in General Merchandise Stores. GMS require stable and mass supply, consistent size, and low price. And Distribution of fresh fish is undertook by the large scale distributers, which can satisfy requirements of GMS. The market share in Tokyo Central Wholesale Market shows Mie Pref. is dominating in live fish. And Ehime Pref. is dominating in fresh fish. Ehime Pref. showed remarkable growth in 1990s. At present, the dealings of live fish is decreasing. However, the dealings of fresh fish is increasing in Tokyo Central Wholesale Market. The price of live fish is decreasing more than one of fresh fish. Even though Ehime Pref. has an ideal natural environment for sea bream aquaculture, its entry into sea bream aquaculture was late, because it was located at a further distance to consumers than the competing producing areas. However, Ehime Pref. became the number one producing areas through the sales of fresh fish in the 1990s. The production volume is almost 3 times the production volume of Mie Pref. which is the number two production area. More conversion from yellow tail aquaculture to sea bream aquaculture is taking place in Ehime Pref., because Kagosima Pref. has a better natural environment for yellow tail aquaculture. Transportation is worse than Mie Pref., but this region as a far-flung producing area makes up by increasing the business scale. Ehime Pref. increases the market share for fresh fish by creating demand from GMS. Ehime Pref. has developed market strategies such as a quick return at a small profit, a stable and mass supply and standardization in size. Ehime Pref. increases the market power by the capital of a large scale commission agent. Secondly Mie Pref. is close to markets and composed of small scale farmers. Mie Pref. switched to sea bream aquaculture early, because of the price decrease in aquacultured yellou tail and natural environmental problems. Mie Pref. had not changed until 1993 when the price of the sea bream plummeted. Because it had better natural environment and transportation. Mie Pref. has a suitable water temperature range required for sea bream aquaculture. However, the price of live sea bream continued to decline due to excessive production and economic recession. As a consequence, small scale farmers are faced with a market price below the average production cost in 1993. In such kind of situation, the small-sized and inefficient manager in Mie Pref. was obliged to withdraw from sea bream aquaculture. Kumamoto Pref. is located further from market sites and has an unsuitable nature environmental condition required for sea bream aquaculture. Although Kumamoto Pref. is trying to convert to the puffer fish aquaculture which requires different rearing techniques, aquaculture technique for puffer fish is not established yet.