• 한국IT서비스학회:학술대회논문집
• /
• 2008.05a
• /
• pp.511-515
• /
• 2008

이웃기반 협력 필터링을 이용한 추천시스템은 적은 평가 자료로 인해 추천 성능에 문제가 생긴다. 이는 다른 고객의 정보도 추천에 사용하는 협력 필터링에서 이웃고객 선정에 문제가 생겨 추천시스템의 신뢰가 떨어진다. 본 논문은 추천시스템의 신뢰를 높이기 위한 방법으로 선호도 평가치가 적은 상품을 임계값을 이용하여 선별하고 이에 따라 고객의 표준편차를 조사하였다. 그리고 표준편차가 낮은 고객에 대한 MAE를 분석하여 예측의 정확도가 높아짐을 알 수 있었다.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2005.11a
• /
• pp.171-173
• /
• 2005

커뮤니티 컴퓨팅은 유비쿼터스 컴퓨팅 환경을 기반으로 다양한 요구와 이를 수용하기 위한 서비스 혹은 개체를 나열하는 것 에서부터 이들 간 일시적으로 협력하고 주어진 상황을 효과적으로 인지할 뿐만 아니라 다수의 장치가 협력 관계를 추구하는 컴퓨팅 모델이다. 본 논문은 커뮤니티 모델과 미들웨어의 아키텍처를 확립하기 위한 요구사항과 구조에 대하여 논한다.

• Korean Security Journal
• /
• no.28
• /
• pp.207-228
• /
• 2011

In the situation that crime is diversified qualitatively and quantitatively, the mutual cooperation system between police and private security is very important to cope with the change of policing environment properly. The primary purpose of this study is to suggest the method to improve the policing service quality of police and advance sound security industry by analyzing the case of close mutual cooperation system between police and private security of USA, which can be called the best country in the field of private security. When considering the cases of USA synthetically, we can know that as the most basic characteristic, the discussion over actual cooperation method is performed on the basis of positive recognition over mutual existence of police or private security. It means that the mutual relationship is based on the basic recognition over partner relationship to meet citizen's desire for safety. While reviewing the cases of USA, Korea shall refer to the fact that social safety activities of advanced countries display effects because of many factors such as various mutual cooperation programs between police and private security, efforts of local government, high quality of private security, reliance of citizen and general understanding of police, private security and citizen to solve crime problem. As shown in the review of USA cases, when considering the fact that the mutual cooperation between police and private security is performed in the level of autonomous police, Korea shall perform autonomous police system to provide better policing service, which is close to citizen.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.375-378
• /
• 2002

Most construction works in a building site are progressed by many work categories and sub-contractors. Therefore there are many difficult things of management of construction-information because variable occurrences are happened to manpower and material resources. For this reason, various management systems are suggested, but the application of these systems are difficult because only construction company manages these systems and sub-contractor's participation, understanding and financial ability are insufficient. In addition to that, there are other problems such as lost information when it is carried, perversion and distrust of information by hand and lots of time and labor are necessary for collection, analysis, and management of information which are offered for daily report. so the purpose of this study is for improvement of reporting process with making an analysis of productivity effects and an analysis of function and problem of daily report. I intend to suggest the direction of improved daily report system for better productivity of construction work through input information and management of cooperation enterprises.

• Proceedings of the Korea Contents Association Conference
• /
• 2003.11a
• /
• pp.234-244
• /
• 2003

In distributed file-systems, cooperative caching algorithm which owns the data cached at each node jointly is used to reduce an expense of disk access. Cooperative caching algorithm is the method that increases a cache hit-ratio and decrease a disk access as it holds the cache information of distributed systems in common and makes cache larger virtually. Recently, several cooperative caching algorithms decrease the message costs by using approximate information of the cache and increase the cache hit-ratio by using local and global cache fields dynamically. And they have an advantage that increases the whole field hit-ratio by sending a replaced block to the idel node on cache replacement in order to maintain the replaced block in the cache field. However the wrong approximate information deteriorates the performance, the concistency maintenance goes to great expense to exchange messeges and the cost that manages Age-information of each node to choose the idle node increases. In this thesis, we propose a cooperative cache algorithm that maintains correct cache information, minimizes the maintance cost for consistency and the management cost for cache Age-information. Also, we show the superiority of our algorithm through the performance evaluation.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.48 no.9
• /
• pp.1-9
• /
• 2011

In this paper, we propose an efficient method to create clusters of geographically distributed base stations which cooperatively transmit signals in cellular mobile communication systems. The proposed method utilizes a sequential selection approach to choose candidate base stations which can provide maximum weighted sum-rate gain when they participate in the cooperative transmission with the existing cluster. In particular, the proposed method limits the maximum number of base stations in a cluster by considering the system operational and implementation complexities. Moreover, the combinations of clusters dynamically change along with variations of channel environments. Through computer simulations, performance of the proposed method is verified by comparing with the non-cooperative transmission method and the static clustering method. Numerical result shows that the proposed sequential selection based clustering method is especially advantageous for the performance improvement of lower percentile users in terms of average throughput, and thus the proposed method can effectively improve the fairness among users.

• The Journal of the Korea Contents Association
• /
• v.4 no.3
• /
• pp.71-80
• /
• 2004

In distributed file-systems, cooperative caching algorithm which owns the data cached at each node jointly is used to reduce an expense of disk access. Cooperative caching algorithm is the method that increases a cache hit-ratio and decrease a disk access as it holds the cache information of distributed systems in common and makes cache larger virtually. Recently, several cooperative caching algorithms decrease the message costs by using approximate information of the cache and increase the cache hit-ratio by using local and global cache fields dynamically. And they have an advantage that increases the whole field hit-ratio by sending a replaced buffer to the idle node on buffers replacement in order to maintain the replaced cache in the cache field. However the wrong approximate information deteriorates the performance, the consistency maintenance goes to great expense to exchange messages and the cost that manages Age-information of each node to choose the idle node increases. In this thesis, we propose a cooperative cache algorithm that maintains correct cache information, minimizes the maintenance cost for consistency and the management cost for buffer Age-information. Also, we show the superiority of our algorithm through the performance evaluation.

• Journal of KIISE:Computing Practices and Letters
• /
• v.11 no.2
• /
• pp.165-179
• /
• 2005

Close collaboration among businesses is required in B2B EC environment. Furthermore, emergency requests or critical information among businesses should be processed in an immediate mode. Most current systems, however, due to firewalls for the systems' security and autonomy, can not handle these requirements appropriately, but handle them in an ad hoc manner In this paper a method of timely collaboration among businesses and an active functionality component to support it in B2B EC environment are proposed. Since the active functionality component supports high level ECA rule patterns and event-based immediate processing, system administrators and programmers can easily program and maintain the timely collaboration independently to the application logic. The proposed active functionality component uses HTTP protocol to be applied through firewalls and is designed using a commercial DBMS for practical purpose.

• Journal of Satellite, Information and Communications
• /
• v.8 no.1
• /
• pp.66-70
• /
• 2013

In this paper, Threshold setting method is proposed to improve detection probability for cooperative sensing. Even if cooperative users have all same false alarm rate, each user has different threshold due to pass ad-hoc channel. threshold level is related to detection probability. So, we select the highest threshold among cooperative users and then share threshold information for getting the high detection probability.

• Annual Conference of KIPS
• /
• 2003.05a
• /
• pp.309-312
• /
• 2003

추천 시스템을 위한 여과 기술에는 협력적 여과, 내용기반 여과 등이 있다. 협력적 여과 방법은 적용이 용이한 반면 회소성 문제와 초기 평가 문제가 있으며, 내용기반 여과는 정보의 질을 구분하는 것이 어려워 효과가 적다는 단점이 있다. 신경망 기반 협력적 여과 방법은 이러한 문제를 해결하고 있지만, 사용자의 수가 많아지면 모델이 커져 효율성이 떨어지는 문제가 있다. 본 논문에서는 신경망 기반 협력적 여과의 효율성을 높이기 위해 상관도를 고려하는 신경망 기반 협력적 여과를 제안한다. 여기서 상관도란 피어슨 상관계수를 이용하여 구해진 상관계수의 절대값을 의미하며 상관도가 높다라는 것은 상관계수의 절대값이 1에 가까운 경우를 말한다. 본 논문에서는 EachMovie 데이터를 이용하여 제안한 방법의 우수함을 보인다.