• The Journal of Korean Association of Computer Education
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• v.8 no.6
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• pp.123-132
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• 2005

There are many research results for the location update cost minimization of location management in cellular networks. For minimizing the location update cost, we have to take in consideration of each users' mobility pattern. This paper suggests location area list generation and a 3-step paging method based on users' movement history with the users' profiles. Users' mobility has not only geographical regular patterns but also time-related regularity. So, the method extracts users' movement regularities in both geography and time from their movement history, and generate location area list considering the regularities. For the performance analysis of the suggested method, we have executed a simulation for suggested method with user's mobility model. The results of the simulation show that suggested algorithm has some merits in the location management cost.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.854-859
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• 2002

Location Based Services, or LBS refers to value-added service by processing information utilizing mobile user location. With the rapidly increasing wireless internet subscribers and world LBS market, the various location based applications are introduced such as buddy finder, proximity and security services. As the killer application of the wireless internet, the LBS has preconsidered technology about location determination technology, LBS middleware server for various application, and diverse contents processing technology. This paper describes the open architecture for LBS platform ensuring interoperability among the wireless networks and various location-based application services and the functional requirements for the LBS platform. The LBS platform in a narrow sense provides a standard interfaces for location management and network management for location services as follows, positioning (location acquisition through network or/and handset), location managing, location based functions, profile management, authentication and security, location based billing, information roaming between carriers and the system monitoring independent to specific network or ISP/CPs(Content Providers).

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.610-612
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• 2003

본 논문은 무선 셀룰러 시스템 환경에서 일정구간을 이동하는 지하철, 기차와 같이 규칙적인 이동 패턴을 보이는 운송 매체에 탑승한 사용자들의 이동성을 지원하기 위해 PGLT(Profile­based Group Location Tracking) 기법을 제안한다. 최근 무선 통신 기술의 발전으로 인한 이동 사용자(Mobile Terminal, MT)의 급증은 시그널링 트래픽의 증가로 이어져 결국 위치 관리 비용까지 높아지게 되었다. MT들이 동시에 새로운 등록 영역으로 이동할 때 GLT(Group Location Tracking) 위치 관리 기법에서는 기존 IS­41의 각 사용자들의 개별적인 위치 갱신 요청 대신에 그룹을 이용한 위치 갱신 요청으로써 위치 관리 비용을 줄였다. 그러나 본 논문에서 제안하는 PGLT 기법은 GLT 기법을 향상시킨 기법으로서, 사용자들의 규칙적인 이동 패턴 특성을 살린 프로파일 정보를 이용하여 그룹에 대한 위치 갱신 비용까지도 줄일 수 있다. MSRP­VLR(Mobility Scheduler on Regular Path)과 RMB(Regular path Movement Buffer)를 이용하여 일정구간을 이동하는 TV(Transportation Vehicle)가 위치 갱신 요청을 하면, MSRP­VLR은 이동 경로에 대한 프로파일 정보를 보내어 TV의 RMB에 저장함으로써 그 경로를 이동 시 그룹에 대한 위치 갱신 요청을 할 필요가 없게 된다. 따라서 PGLT 기법은 GLT 기법의 그룹 위치 갱신 비용을 줄임으로써 일정구간을 이동하는 TV에 탑승한 많은 사용자들에 대한 위치 관리 비용을 현저히 줄일 수 있다.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.3
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• pp.91-108
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• 1998

Automated Storage and Retrieval Systems (AS/RSs) are an important facility for modern material management. The expected benefits of these capital-intensive facilities are gained when their control policies and their physical design parameters are determined simultaneously. In this paper we present several analytical models that capture the impact of the storage assignment policy and of the rack design on the expected storage and retrieval times. Sequential and interleaved service modes are considered for sequencing the storage and retrieval requests. We further investigate the impact of the rack structure on the relative performance of the following storage assignment policies : closest open location (random), full turnover-based policy, and class-based. Our analysis clearly indicates that significant savings in crane travel time are realized when implementing full turnover-based policy, rather than random. These savings become more and more pronounced as the profile of the storage racks approaches the square-in-time shape. Furthermore, it is shown that a class-based policy, with a small number of storage classes, will capture most of these savings and be easier to manage in practice.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.568-572
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• 2007

With the proliferation of advanced wireless network and sensor technologies, smart devices under USN(ubiquitous sensor network) environment are capable of collecting context information such as temperature, humidity, weight, and location about objects at real time. Therefore, applications must be able to analyze collected information and notify useful information to wanted users timely. This service can be realized by implementing an event-based middleware. In the middleware, event messages collected from physical environment will be filtered according to profiles that users define in advance and the result will be sent to the interested users. In this paper, we present XML-based event model, ECA-based profile model, and the architecture of an event-based middleware suitable to USN environment. We will also model and describe them using the examples of logistics area. By implementing the system based on the design above, the middleware enable applications or users to easily access to physical sources. The proposed middleware can also apply to not only logistics area but also other various areas under USN environment such as intelligent traffic control system, national disaster management system and u-medical system.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.81-84
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• 2007

In this research, we will accomplish the investigation of the devices and data models which are used in the existing indoor and outdoor systems. Based on the investigation, we will seize the additional requirements for the integration of the legacy system and then we will propose the various methods which support the additional requirements. By applying the various methods in the heterogeneous environments, we will solve the legacy problems and propose the methods for the final goal that is to provide the seamless moving object tracking. The scope of this research is to propose the integration methods, developing the actual location tracking system model without modifying the legacy infrastructures.

• Human Ecology Research
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• v.61 no.3
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• pp.335-348
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• 2023

The purpose of this study was to identify: (a) the latent profiles of the difficulties associated with the schoolto-work transition (decline in confidence, mood swings, family disagreements, the burdens of familial expectations, economic hardship, and a lack of support) made by university students, (b) predictors (gender, age, grade, university location, co-residence with parents on weekdays, monthly household income, and parental educational attainment) of these profiles, and (c) how the profiles were associated with mental wellbeing. The participants of this study were 311 senior or above students (164 males and 147 females) under the age of 29, who were unmarried and preparing for employment. The findings of this study were as follows. First, the latent profile analysis revealed three distinct profiles: the "low overall difficulties" type (25.4%), the "moderate overall difficulties" type (49.9%), and the "high overall difficulties" type (24.7%). Second, the factors that predicted each profile included gender, age, co-residence with parents on weekdays, monthly household income, and parental educational attainment. Third, the "low overall difficulties" type demonstrated the highest level of mental well-being (emotional, social, and psychological well-being). This study was significant for examining the latent profiles of the difficulties associated with the school-to-work transition made by university students preparing for employment, while also exploring their mental well-being. Based on the results of this study, practical implications, limitations, and suggestions for further study were discussed.

• International Journal of Contents
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• v.17 no.4
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• pp.16-34
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• 2021

The purpose of this study was to explore how designers use software-based design tools for ideation and collaboration (for two cases: with designers and with developers). We conducted logistic regression analysis and random forest analysis. Software-based design tools are more popular among product designers and affiliated with design organizations with 51 to 100 members. We identify the features that influence designers to use design tools for the ideation and collaboration, and how these usage patterns are interrelated. Interrelated usage pattern is a key consideration for location of the menu and convenience of use. The results imply that reinforcement of the design tool features per designer profile is required and that design management should be consistent with the field of design and the nature of the organization.

• Asia pacific journal of information systems
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• v.14 no.3
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• pp.121-144
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• 2004

Developing a personalized system on a user's behalf which is working around the Internet-based marketplace is one of the challenging issues in intelligent e-business, especially mobile commenrce. It has been highly recommended that such a mobile personalized system has to perceive the user's needs a priori by tracking user's current context such as location with activity and then to identify the current needs dynamically and proactively. Automatically and unobtrusively getting user's context is an inevitable feature for the development of autonomous mobile commenrce. However, personalization methodologies and their feasible architectures for context-aware mobile commerce have been so far very rare. Hence, this paper aims to propose a context-aware mobile commerce development methodology by applying agent and semantic web technologies for personalized reminder system, which is one of the mobile commerce support system. We revisited associationism to understand a buyer's need identification process and adopt the process as 'purchase based on association' to implement a personalized reminder system. Based on this approach, we have showed how the agent-based semantic web service system can be used to realize need-aware reminder system. NAMA(Need-Aware Multi-Agent), a prototype system, has been implemented to show the feasibility of the methodology and framework under mobile setting proposed in this paper. NAMA embeds bluetooth-based location tracking module and identify what a user is currently looking at through her/his mobile device such as PDA. Based on these capabilities, NAMA considers the context, user profile with preferences, and information about currently available services, to aware user's current needs and then link her/him to a set of services, which are implemented as web services.

• Journal of the Korea Society of Computer and Information
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• v.14 no.8
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• pp.117-125
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• 2009

In this paper, an integrated management system of seismic observatory information based on XML is proposed. The number of organizations which have their own seismic stations eg. KMA, KIGAM etc is increasing since 1998. Related informations such as location, installed instruments. and operational profile are essential for efficient utilization of seismic data. It's not easy to provide the uniform type of information and has limitation to announce the updated information of station rapidly through individual information management system of each organization. In this paper, we propose an integrated management system of seismic observatory information which can support to manage information of their own seismic observatory by a person in charge via Web, to integrate that in nation-wide and to provide that for users. We investigated minimum information of observatory were needed to use seismic data and the analysis result was structured by using XML. The integrated management system consists of the observatory management module. information search module, and the latest information supply module etc. By using proposed system, seismic observatory information of each organization can be managed and be supplied efficiently in nation-wide.