• Journal of Communications and Networks
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• v.16 no.1
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• pp.1-9
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• 2014

Block diagonalization (BD) has been proposed as a simple and effective technique in multiuser multiple-input multiple-output (MU-MIMO) broadcast channels. However, when channel state information (CSI) knowledge is limited at the transmitter, the performance of the BD may be degraded because inter-user interference cannot be completely eliminated. In this paper, we propose an efficient CSI quantization technique for BD precoded systems with limited feedback where users supported by a base station are selected by dynamic scheduling. First, we express the received signal-to-interference-plus-noise ratio (SINR) when multiple data streams are transmitted to the user, and derive a lower bound expression of the expected received SINR at each user. Then, based on this measure, each user determines its quantized CSI feedback information which maximizes the derived expected SINR, which comprises both the channel direction and the amplitude information. From simulations, we confirm that the proposed SINR-based channel quantization scheme achieves a significant sum rate gain over the conventional method in practical MU-MIMO systems.

• Women's Health Nursing
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• v.21 no.3
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• pp.241-251
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• 2015

Purpose: The purpose of this study was to explore preserved belief system supporting Korean immigrant women's Taekyo practices and influencing factors while they observe the tradition within US sociocultural context. Methods: Leininger's exploratory focused ethnographic approach was used. Semi-structured in-depth interviews were conducted with purposive sample of sixteen Korean immigrant women who gave birth in the US within last 6 months. Researcher's observation and reflective field notes were also integrated into the interview data. Leininger and McFarland's four phases of ethnographic analysis guided data analysis process. Results: The perceived belief system supporting Taekyo practices included Taekyo as an enculturated Korean tradition, connecting parents with fetus, and positive impacts on fetal development. And Korean immigrant women's Taekyo practices were influenced by resources of information, woman's orientation toward Taekyo, pressure from local Korean community, and child order. Conclusion: The findings from this research would serve as an important knowledge base to expand US health care providers' understanding of Korean traditional Taekyo practices observed by Korean immigrant women's as important prenatal self-care practices. The findings could also aid in providing more patient-centered and culturally-tailored prenatal care plan to Korean immigrant by including Korean traditional belief system supporting Taekyo practices.

• Journal of Korean Society of Transportation
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• v.14 no.1
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• pp.51-67
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• 1996

The optimal path-finding problem becomes complicated when multiple variables are simultaneously considered such as physical route length, degree of congestion, traffic capacity of intersections, number of intersections and lanes, and existence of free ways. Therefore, many researchers in various fields (management science, computer science, applied mathematics, production planning, satellite launching) attempted to solve the problem by ignoring many variables for problem simplification, by developing intelligent algorithms, or by developing high-speed hardware. In this research, an integration of expert system technique and case-based reasoning in high level with a conventional algorithms in lower level was attempted to develop an optimal path-finding system. Early application of experienced driver's knowledge and case data accumulated in case base drastically reduces number of possible combinations of optimal paths by generating promising alternatives and by eliminating non-profitable alternatives. Then, employment of a conventional optimization algorithm provides faster search mechanisms than other methods such as bidirectional algorithm and $A^*$ algorithm. The conclusion obtained from repeated laboratory experiments with real traffic data in Seoul metropolitan area shows that the integrated approach to finding optimal paths with consideration of various real world constraints provides reasonable solution in a faster way than others.

• Journal of the Korea Society of Computer and Information
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• v.6 no.2
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• pp.48-57
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• 2001

In a fuzzy connectionist expert system(FCES), the knowledge base can be constructed of neural logic networks to represent fuzzy rules and their relationship, We call it fuzzy rule inference network. To find out the belief value of a conclusion, the traditional inference strategy in a FCES will back-propagate from a rule term of the conclusion and follow through the entire network sequentially This sequential search strategy is very inefficient. In this paper, to improve the above search strategy, we proposed fuzzy rule inference rule used in a FCES was modified. The proposed adaptive search strategy in fuzzy rule inference network searches the network according to the search priorities.

• Archives of design research
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• v.13 no.3
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• pp.313-320
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• 2000

Currently, The new wave of information technology has enormously influenced every field. In the Held of design, it is time to strive possible efforts in order to accumulate the design-related knowledge by maintaining, managing and controlling design information in a systematic manner, getting out of the old stage of mere use of data itself. Due to remarkable progress in communication media and speed, and file compression technology, text-centric data has been shifting to multimedia data such as image and motion picture. So it is currently required that methologies be developed to effectively utilize the related information. With respect to the processing of image data, it is certain that the optimal method should be come up with reflecting the unique characteristics and utilization of image data, apart from the traditional way of processing and storing the legacy text-based data. The study suggests the system of indexing and implementing design image information through the case of analyzing design image data, abstracting data elements of image itself, and finally applying it to building image-oriented database for use.

• Journal of KIISE:Software and Applications
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• v.31 no.3
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• pp.353-360
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• 2004

Ontology defines the terms used in a specific domain and the relationships between them and represents them as hierarchical taxonomy. The present paper proposes a semi-automatic domain-specific ontology construction method based on terminology Processing. For this purpose, it presents an algorithm to extract terminology according to the noun/suffix pattern of terminology in domain texts and find their hierarchical structure. The experiment was carried out using pharmacy-related documents. As singleton terminology with noun/suffix were identified, the average accuracy was 92.57%. In case of multi-word terminology, the average accuracy was 66.64%. The constructed ontology forms natural semantic clusters with based on suffices and semantic information, so can be utilized in approaches to specific knowledge such as information look-up or as the base of inference to improve searching abilities.

• Annual Conference on Human and Language Technology
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• 2003.10d
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• pp.177-183
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• 2003

기존의 정보검색시스템이 사용자의 질의에 의해 키워드가 포함된 의미 있는 문서를 제공하는 시스템이라면, 질의응답시스템은 사용자 질의에 맞는 정답을 적절한 언어처리 기법을 통해 텍스트로부터 추출하여 제공하는 시스템이다. 이러한 언어처리 기법을 이용한 질의응답 시스템에서 시스템의 성능 향상에 도움을 줄 수 있는 것이, 실세계의 지식을 저장하고 있는 지식베이스라 할 수 있다. 지식베이스가 가지고 있는 실세계의 지식을 어떻게 효율적으로 활용하느냐에 따라 질의 처리 분석과 정답 확률을 향상시킬 수 있는 것이다. 본 논문에서는 실세계의 지식을 어느 정도 체계적 의미적으로 반영하고 있는 것을 백과사전으로 판단하여, 백과사전의 '인물' 범주(category)를 중심으로 백과사전 지식베이스의 틀을 마련하고자 하였다. 또한 어휘의 계층적 구조를 중심으로 한 온톨로지를 백과사전 지식베이스와 유기적으로 연결시킴으로써 보다 의미 있는 지식베이스를 형성하는 방안을 모색하고자 하였다.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.4
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• pp.777-782
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• 2012

This paper proposes a technique for improving performance using word senses and user feedback in web information retrieval, compared with the retrieval based on ambiguous user query and index. Disambiguation using query word senses can eliminating the irrelevant pages from the search result. According to semantic categories of nouns which are used as index for retrieval, we build the word sense knowledge-base and categorize the web pages. It can improve the precision of retrieval system with user feedback deciding the query sense and information seeking behavior to pages.

• Culinary science and hospitality research
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• v.8 no.3
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• pp.169-185
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• 2002

Data collections were made from the Seoul five-star hotels'Italian restaurant to set goals on the quantity standardization by bringing up the issues from the analysis of their menus and portions. Brief of this research is as follows. The first, variations of Italian cuisine are significantly different from the region to region. The chef or cook must have general knowledge and understanding, and consider the ingredients and its cooking method. The second, for the understanding of fire Italian menu, languages used for the menu have to be in worldwide understandable languages and for the better understanding of Korean chefs, it should be also described in Korean. The third, for the cost controller and to reduce the cost, all food should be prepared in proper cooking method and set goal for the right portion size. The fourth, menu should be selected based on the customer preferences and the menu cycle change is adequate for four times a year. Italian food and dishes are prepared by above points with the standardized portion size and cooking method, more efficient and uniformed dishes will be provided to customers and customers will be fulfilled with the satisfaction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.3
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• pp.291-301
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• 2015

Product regulations specify requirements or constraints for products that manufacturers must comply with across the entire product lifecycle, from design and manufacture, through operation and maintenance, to recycling and disposal. This paper suggests a system framework and its essential components for the verification of a pressure vessel design using the industrial standards of Korea. The authors also present methods to generate design template data from legacy design systems and to construct a regulation knowledge base. The proposed framework is demonstrated through experiments involving pressure vessel design verification using a prototype system.