• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.6B
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• pp.316-324
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• 2007

In this paper we proposed an energy consumption model for IR-UWB wireless sensor networks. The model takes the advantages of PHY-MAC cross layer design, and we used slotted and un-slotted sleeping protocols to compare the energy consumption. We addressed different system design issues that are responsible to energy consumption and proposed an optimum model for the system design. We expect the slotted sleeping will consume less energy for bursty load than that of the un-slotted one. But if we consider latency, the un-slotted sleeping model performs better than the slotted sleeping case.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.550-555
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• 2011

Utilizing construction knowledge and experiences in design phase can reduce change orders and improve productivity in construction phase. To do so, information must be made available to the design team in time. Current approaches for effective utilization of constructability knowledge, however, only focus on the formalization of constructability knowledge such as a checklist, which lacks the consideration of the appropriate use at the proper point in time. The inadequate use of constructability knowledge can result in unnecessary reworks. To deal with this problem, the design team needs to know what constructability knowledge is required for specific design activities in the design process. This paper presents a constructability implementation model using the dependency structure matrix (DSM) that focuses on information flows between design activities and constructability knowledge. For this objective, design activities in the design process are modeled in a matrix form based on their dependency. Then, constructability knowledge, which needs to be considered in the design stage, is mapped into activities and incorporated into the matrix, creating Constructability-DSM (C-DSM). Next, the partitioning algorithm is applied to C-DSM for optimal information flow. The Partitioned C-DSM is then analyzed based on the relationship between activities. Finally, the optimal utilization of construction knowledge in the design process is determined by identifying what constructability knowledge is required for each design activity, and how and when it is reflected to design for constructability. Thus, this research can help provide robust control actions to reduce unnecessary iterative cycles in design process for efficient constructability implementation.

• The Research Journal of the Costume Culture
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• v.19 no.5
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• pp.1031-1048
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• 2011

The purpose of this study was to investigate the status of domestic and foreign power blogs that serve as professional source of information and to clarify the difference of the criteria for the certification and selection of power blogs. The study also analyzed the configuration of contents and the characteristic of categories of the power blogs. Eleven domestic blogs were examined, of which ten were certified as power blogs on several portal sites and one blog was operating in English. Furthermore twelve foreign blogs were examined, of which ten blogs were selected from the graded list of www.alexa.com for the Fashion Power Blog TOP 20 adopted on www.telegraph.co.uk in 2009, and two noticeable blogs were selected additionally. Data were analyzed by both theoretical and exploratory studies. The exploratory study was conducted by fourteen majors, who took interest in the blogs and were divided into two groups to look at the domestic and foreign sites, from 12 October to 12 November in 2010. The types of blogs were classified by frequency analysis of interactivity, interest provision, information provision and purchase capability. The investigators checked the type of the contents of each blog and the frequencies were used for the classification type. The analysis showed that the frequencies were in the order of information provision, followed by interest provision, and purchase capability for foreign blogs, while interest provision was followed by information provision for domestic blogs. Interactivity, interest provision, information provision and purchase capability were generally reflected in foreign blogs. Rather than interest provision and information provision, however, interactivity and purchase capability were reflected relatively weakly in domestic blogs.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1318-1323
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• 2009

In recent years, dramatic advances in information technology have motivated the construction industry to improve its productivity. Computer-based information technology includes Computer-Aided Design (CAD), Computer-Aided Engineering (CAE), Computer-Aided Manufacturing (CAM), Enterprise Resource Planning (ERP), Digital Mock-Up (DMU) and Product Data Management (PDM). Most construction industries are trying to apply these technologies for quality improvement, reduction of construction time and cost. PDM is very useful for managing data and process related to product design and manufacturing. PDM system has various functions such as drawing and engineering document management, product structure and structure modification management, part classification management, workflow management, and project management. In this paper, PDM system was applied to the design of steel-concrete composite girder bridge. To make a practical guidance for PDM implementation to bridge design, the procedure for its implementation was presented. Consequently, this paper could be useful to enhance the efficiency of bridge design.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.566-569
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• 2013

The purpose of this research is to develop the technology to meet the requirements of the design content, and to build a 'Requirement Information Management Model' for the design project. The model that should be used in the early design stage will undergo the following process: First, basic requirements would be defined by extracting the design content in the form of a reusable library of space units. At the next stage, requirement information should be modified after considering unique characteristics for the project and conflict problems between function and performance.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.4
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• pp.197-202
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• 2001

This paper proposes a design method for improving the disassembly by using the axiomatic approach. A product developer must design disassembly as well as assembly when designing the structure of a product. Axiomatic approach is a design tool that optimizes design. In this paper design evaluation method using information axiom sets impact variables and value function. As a result, examining the relationship between the functional requirements and evaluating the information can optimize designs.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.493-494
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• 2008

LGP for the small size exit was designed and fabricated. Pattern design method, which is the most important thing in the design of the LGP, was converted from the line type into the cross type. By using this new method, the brightness unevenness, which was very difficult problem to be solved in V-cutting method, was improved. Currently products had 78% of the brightness uniformity but newly developed product in this research had 87% of the brightness uniformity. Also the optimized design rule provided the improvement of the brightness of the LGP developed in this study, that has brightness of $871cd/m^2$ whichwas 98% higher than the common products.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.5
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• pp.1654-1675
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• 2014

In practical wireless systems, the erroneous channel state information (CSI) sometimes deteriorates the performance drastically. This paper focuses on robust design of coordinated set planning of coordinated multi-point (CoMP) transmission, with respect to the feedback delay and link error. The non-ideal channel models involving various uncertainty conditions are given. After defining a penalty factor, the robust net ergodic capacity optimization problem is derived, whose variables to be optimized are the number of coordinated base stations (BSs) and the divided area's radius. By the maximum minimum criterion, upper and lower bounds of the robust capacity are investigated. A practical scheme is proposed to determine the optimal number of cooperative BSs. The simulation results indicate that the robust design based on maxmin principle is better than other precoding schemes. The gap between two bounds gets smaller as transmission power increases. Besides, as the large scale fading is higher or the channel is less reliable, the number of the cooperated BSs shall be greater.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.897-900
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• 2006

RFID(Radio Frequency Identification) 기술의 발전은 편의성과 경제성으로 전 세계에 확산되어 사용되고 있다. 비록 세계적인 보안 표준안이 정해 지지 않았지만 RFID 보안 분야는 각 나라에 맞게 표준을 선정하여 적용되고 있다. 한편, RFID 기술의 발전으로 RFID의 칩이 소형화되고, 장거리 통신이 가능해짐에 따라 RFID 시스템에 내장된 정보를 다른 누군가가 활용하여 개인 또는 기업 등의 프라이버시를 불법으로 수집하는 피해가 발생할 수 있다. 본 논문은 RFID 시스템에서 정보의 누출을 막기 위해 해쉬 알고리즘과 초경량 스트림 암호알고리즘을 사용하여 전방위 안전성이 향상된 RFID시스템을 제안, 분석하였다.

• International Journal of Contents
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• v.7 no.3
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• pp.48-59
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• 2011

The present thesis is on a construction of the system which supports exhibition evaluation of curators, which automatically collects, keeps, and totalizes objective data on visitor behavior in museums, and which comprehensively displays the results by tables and graphs. The system is composed by access points and mobile exhibition exposition devices in the museum operating together. Obtainable visitor information include a user number, an average staying period, contents use hour, and exhibition viewing frequency. Prototype experiment at museums shows that the system is effective in efficient data collection and exhibition evaluation and is expected to become an information collecting tool for visitor research and an exhibition evaluation tool for exhibition improvement.