• Title/Summary/Keyword: knowledge-base

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Design and BER Performance Evaluation for Digital Retrodirective Array Antenna systems (디지털 역 지향성 배열 안테나 시스템 설계와 성능 평가)

  • Kim, So-Ra;Lee, Seug Hwan;Shin, Dong Jin;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.3
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    • pp.217-223
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    • 2013
  • A digital retrodirective antenna system is easy to modify and upgrade because it can control the phase information of the output signal toward opposite direction to input signal without a priori knowledge of the arrival direction. Due to this advantage, it is possible to perform fast beam tracking. In this paper, a design digital retrosirective array antenna system according to the number of antenna array by using only one digital PLL which finds angle of delayed phase and we test BER performance of this system. When we transmit data at actual communication system, the data modulated onto carrier frequency in order to shift spectrum from base band to another band. So we simulate system considering carrier frequency according to the number of antenna array. As a result, carrier frequency has no impact on the performance.

A Study on Development of Integrated OPAC Based on Hypermedia Techniques (하이퍼미디어 기술에 기반한 통합 OPAC구현에 관한 연구)

  • Ahn, Tae Kyoung;Kim, Hyun Hee
    • Journal of Information Management
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    • v.27 no.1
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    • pp.1-39
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    • 1996
  • The purpose of this paper is to design a model of integrated OPAC called as EconRef. This model not only provides users of libraries with systematic, rapid information service, but also supports librarians to do their tasks effectively. The designed model is constructed based on two operating systems such as REGIS system and The Book House and is developed by using KPWin++ is an expert system shell which combines hypertext and expert system functions. The designed system consists of six modules ; three reference expert systems for document sources, experts and statistical sources; OPAC ; external database ; user's guide. For the evaluation of the designed system, performance of EconRef system is compared with that of the naive and expert reference librarians. And also the features of the system are compared with those of REGIS systems. The tests comparing BconRef system searching with librarians searching have shown that EconRef system is at least as good as searching with expert librarians and much superior to searching with naive librarians.

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A Study on an Automatic Summarization System Using Verb-Based Sentence Patterns (술어기반 문형정보를 이용한 자동요약시스템에 관한 연구)

  • 최인숙;정영미
    • Journal of the Korean Society for information Management
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    • v.18 no.4
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    • pp.37-55
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    • 2001
  • The purpose of this study is to present a text summarization system using a knowledge base containing information about verbs and their arguments that are statistically obtained from a subject domain. The system consists of two modules: the training module and the summarization module. The training module is to extract cue verbs and their basic sentence patterns by counting the frequency of verbs and case markers respectively, and the summarization module is substantiate basic sentence patterns and to generate summaries. Basic sentence patterns are substantiated by applying substantiation rules to the syntactics structure of sentences. A summary is then produced by connecting simple sentences that the are generated through the substantiation module of basic sentence patterns. ‘robbery’in the daily newspapers are selected for a test collection. The system generates natural summaries without losing any essential information by combining both cue verbs and essential arguments. In addition, the use of statistical techniques makes it possible to apply this system to other subject domains through its learning capability.

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Parry-Romberg syndrome with ipsilateral hemipons involvement presenting as monoplegic ataxia

  • Lee, Yun-Jin;Chung, Kee-Yang;Kang, Hoon-Chul;Kim, Heung Dong;Lee, Joon Soo
    • Clinical and Experimental Pediatrics
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    • v.58 no.9
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    • pp.354-357
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    • 2015
  • Parry-Romberg syndrome (PRS) is a rare, acquired disorder characterized by progressive unilateral facial atrophy of the skin, soft tissue, muscles, and underlying bony structures that may be preceded by cutaneous induration. It is sometimes accompanied by ipsilateral brain lesions and neurological symptoms. Here we present the case of a 10-year-old girl with right-sided PRS and recurrent monoplegic ataxia of the left leg. At 4 years of age, she presented with localized scleroderma over the right parietal region of her scalp; her face gradually became asymmetric as her right cheek atrophied. Brain magnetic resonance imaging revealed hemiatrophy of the face and skull base, and T2-weighted images showed increased signal in the right hemipons and hemicerebellar peduncle. Magnetic resonance angiography findings were unremarkable. She was treated with oral prednisolone, and her recurrent gait ataxia diminished within 2 months of the follow-up period. To the best of our knowledge, this is only the second case of PRS presenting with an abnormal involvement of the ipsilateral hemipons.

A Study on Determinants of Stockpile Ammunition using Data Mining (데이터 마이닝을 활용한 장기저장탄약 상태 결정요인 분석 연구)

  • Roh, Yu Chan;Cho, Nam-Wook;Lee, Dongnyok
    • Journal of Korean Society for Quality Management
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    • v.48 no.2
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    • pp.297-307
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    • 2020
  • Purpose: The purpose of this study is to analyze the factors that affect ammunition performance by applying data mining techniques to the Ammunition Stockpile Reliability Program (ASRP) data of the 155mm propelling charge. Methods: The ASRP data from 1999 to 2017 have been utilized. Logistic regression and decision tree analysis were used to investigate the factors that affect performance of ammunition. The performance evaluation of each model was conducted through comparison with an artificial neural networks(ANN) model. Results: The results of this study are as follows; logistic regression and the decision tree analysis showed that major defect rate of visual inspection is the most significant factor. Also, muzzle velocity by base charge and muzzle velocity by increment charge are also among the significant factors affecting the performance of 155mm propelling charge. To validate the logistic regression and decision tree models, their classification accuracies have been compared with the results of an ANN model. The results indicate that the logistic regression and decision tree models show sufficient performance which conforms the validity of the models. Conclusion: The main contribution of this paper is that, to our best knowledge, it is the first attempt at identifying the significant factors of ASPR data by using data mining techniques. The approaches suggested in the paper could also be extended to other types ammunition data.

New Classification Criteria and Database Code of Water Environment for Nature-Friendly River Work and Integrated Management of Watershed (자연친화적 하천사업 및 통합적 유역 관리를 위한 새로운 수환경 분류법 및 자료관리 프로그램의 개발)

  • Noguchi, Masato;Kang, Sang Hyeok;Kim, Joon Hyun;Nishida, Wataru;Fujisaki, Nobuhito
    • Journal of Environmental Impact Assessment
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    • v.7 no.2
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    • pp.103-112
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    • 1998
  • Nature-friendly river project has became common practice in Japan. In order to make it available for the conservation and rehabilitation of desirable water environment, water criteria for water environmental assessment must be established. Especially, the criteria estimating the effects on ecosystem in and around river should be constructed. In this paper, classification method for water quality has been developed using biological indices and applied to observed data in Honmyo River, Nagasaki, Japan. Modified PI method (BI') has been suggested and those of three most abundant species resulted effective estimate for an overall water quality with comparatively simple procedure. Extensive database management code was prepared for the comprehensive ecological monitoring of river basin, which includes various biota. That system enables easy access of all the ecological data for a dissemination of a sound and sustainable water environment. The result of this study could improve knowledge base, serve making consensus for citizens, and help river management plans. In Japan, citizen's realization and action are the most critical factor for nature-friendly river restoration project.

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Catching-up to the Market Leader: Role of Entry Time-lag, Alliance, and Capability in the Catch-up Success (기술 사업화에 있어 후발자의 시장 추격 전략: 진입시간차, 기업의 역량 및 제휴 관점에서)

  • Kim, Hye-Jun;Chang, Sung-Yong;Song, Jae-Yong
    • Journal of Technology Innovation
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    • v.20 no.1
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    • pp.141-167
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    • 2012
  • Along with technological innovation, successful market entry of a new product is important for sustainable innovation of a firm. In this paper, we examined factors that affect successful introduction of new branded drugs in pharmaceutical industry. Under competing theories of the first mover's advantage and the late mover's advantage, this research focuses on how latecomers can overcome the disadvantages of late entry and catch up to the market leader. First, late movers can absorb the knowledge leaked from pioneering product during the time lag between early entrants and late entrants. Therefore, the time lag provides late entrants an opportunity to catch-up to market leader by differentiating and improving the quality of new product. Second, superior marketing capability of late entrants can enhance the possibility of catching-up, by overcoming the consumer base of early entrants.

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Exploratory Research on the Fidelity Management and the Digitalization of New Product Development Process (신제품 개발과정의 디지털화와 현실반영 정확도 관리에 대한 탐색적 연구)

  • Im, Chae-Seong;Kim, U-Bong
    • Journal of Technology Innovation
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    • v.16 no.2
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    • pp.65-94
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    • 2008
  • There has been rapid diffusion of digital innovation technology(DIT) such as 3 D CAD, CAE, simulation software which enable firms to see the future results of intended product designs through 3 D diagram and simulated results. This technology helps firms to reduce trial and error process by solving later stage problems in earlier stages. The DIT being the technology reflecting the real world, as a tool representing the simplified form of the real world, the degree of reflecting the real world(fidelity) is important in utilizing the DIT. This study is an exploratory research examining the process of reviewing the fidelity of the DITs and developing the complementary process necessary for utilizing the DIT with 'not good enough' fidelity. This study could draw out, from its case study, an exploratory hypothesis about the process of developing the complementary process. In the process, there is an analysis of the corresponding relationship between the actual data and the output data of the DIT, e.g. simulated result. Then the input data or output data are adjusted on the basis of the analysis of the corresponding relationship so that the discrepancy between the actual data and the expected interpretation of the output data, through the adjustment, of the DIT, can be reduced. This process is sometimes accompanied by the process of generating experimental data, which reflect the unique situation of the product development process of a company, to be put to the data base of DIT. The complementary process is the process requiring knowledge sharing and adjustment activities across different divisions. This study draw outs implications for effective management of the fidelity of DIT tools.

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Research on Function and Policy for e-Government System using Semantic Technology (전자정부내 의미기반 기술 도입에 따른 기능 및 정책 연구)

  • Jang, Young-Cheol
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.5
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    • pp.22-28
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    • 2008
  • This paper aims to offer a solution based on semantic document classification to improve e-Government utilization and efficiency for people using their own information retrieval system and linguistic expression. Generally, semantic document classification method is an approach that classifies documents based on the diverse relationships between keywords in a document without fully describing hierarchial concepts between keywords. Our approach considers the deep meanings within the context of the document and radically enhances the information retrieval performance. Concept Weight Document Classification(CoWDC) method, which goes beyond using existing keyword and simple thesaurus/ontology methods by fully considering the concept hierarchy of various concepts is proposed, experimented, and evaluated. With the recognition that in order to verify the superiority of the semantic retrieval technology through test results of the CoWDC and efficiently integrate it into the e-Government, creation of a thesaurus, management of the operating system, expansion of the knowledge base and improvements in search service and accuracy at the national level were needed.

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The Current State of Clinical Studies on Scalp Acupuncture - Treatment for Dementia-by Search for China Literature published from 2001 to 2011 in CAJ(China Academic Journals) - (치매환자의 두침(頭鍼)치료에 대한 최신 임상연구 동향 -CAJ (China Academic Journals: 중국기간전문수거고(中国期刊全文数据库))의 2001~2011년 검색을 통하여-)

  • Lee, Go-Eun;Park, Jang-Ho;Yang, Hyun-Duk;Heo, Eun-Jung;Jeon, Won-Kyung;Lyu, Yeoung-Su;Kang, Hyung-Won
    • Journal of Oriental Neuropsychiatry
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    • v.23 no.2
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    • pp.13-32
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    • 2012
  • Objectives : The purpose of this study was to obtain some knowledge concerning the scalp acupuncture treatment on patients with dementia for the future practice and research from clinical studies in China. Methods : The literatures were searched using the data base-China Academic Journals(CAJ) (2001-2011). Results : We found out 1 case study, and 17 randomized controlled trials(RCT) which met the inclusion criteria in most studies. There were 3 types of scalp acupuncture-applying method, cho-si scalp acupuncture(焦氏頭鍼法), combination of using ordinary acupoints(正經鍼) and extraordinary acupoints(經外寄穴), standard method of scalp acupuncture(標準頭鍼法). The often used acupoints are Yundongqu(運動區), Ganjuequ(感覺區), Yuntingqu(暈聽區), Zuyunganqu(足運感區), Sishencong (HN23), Baihui(GV20), Shenting(GV24), Fengchi(GB20), Dingnieqianxiexian(MS6), and Dingniehouxiexian(MS7). Conclusions : There were significant improvements on the scalp acupuncture-treated groups, compared to the control groups(western medication group or other acupuncture treatment group). Results of this study could be used for future studies concerning the scalp acupuncture for dementia.