• 제목/요약/키워드: Recommended System

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교통신호의 자동최적점제어를 위한 마이크로파 FM-CW 검지계통에 관한 연구 (A Study on Microwave-FM-CW Detection System for the Sutomatic Optimal Point Traffic Control)

  • 양흥석;김호윤
    • 전기의세계
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    • 제22권1호
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    • pp.35-41
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    • 1973
  • An automatic point traffic control method is recommended for more idealistic traffic flow over coarse road netowrks. The automatic control apparatus recommended, consists of a transceiver, amplifier, digital-to-analog converter, signal light controller for emergency and steady state, and digital counter as monitor. The transmitter sends a signal to the target vy means of Microwave-FM-CW and a diode detector picks up the echo signal. Thus the operation of the entire system will be carried out through an open loop state. Some factors necessary for an ideal detector system are rapid response, longevity and stability. An analytical method of the Doppler effect substitutes the conventional frequency deviation into the amplitude of detector output. The changing rate of amplitude is proportional to the voltage of the detector output. Some induced formula from Maxwell's radiation field theory ensures this new method, and, new method, and proves the fact with an experimental data presentation. Stability depends upon Klystron as an oscillator and a diode as a detector. the transceiver installation affects on the response and sensitivity of the system. In accordance with the detector output, several targets are easily classified by amplitudes on the scope. The traffic flow, i.e., target movement which is analyzed by the amplitude method, is shown through the scope and indicates it on the digital counter. The best efficiency for the amplitude analysis can be attained through use of an antenna having the highest sensitivity.

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부산시(釜山市) 청소년(責少年)의 반주행위(飯酒行爲)에 관한 연구(硏究) - 사회심리적(社會心理的) Model에 의한 분석(分析) - (Adolescent Drinking Behaviors in Pusan City : An Analysis on the Sociopsychological Model)

  • 고정자
    • 아동학회지
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    • 제7권2호
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    • pp.55-73
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    • 1986
  • This study analyzed the socio-psychological process of adolescent drinking behaviors. A total 1,732 high school students in Pusan city were studied by the questionnaire from May to July, 1985. A structural model based on review of the literature was examined in order to test the following three hypotheses: (1) sociocultural and environmental impact on the adolescent belief system for drinking, on drinking situations, and on experiences of deviation, (2) relationships among adolescent belief system, drinking situations, and experiences of deviation, and (3) impact of antecedent variables on adolescent drinking levels. All hypotheses were supported by the data. The important outcomes were discussed as follows: 1. Because interpersonal factors were influential for the adolescent belief system concerning drinking, public drinking education through mass communication or drinking education in the curriculum were recommended. In addition to sex variables, friends' drinking and sibling's drinking were shown to have a positive impacts on drinking situations. Also, adolescent self-reported parents' views on drinking had significant effects. Because adolescent deviant experiences were generally affected by environmental factors, it is recommended that positive extra-curricular activities at both home and school should be investigated. 2. There were significant relationships among adolescent belief systems, drinking situations, and deviant experiences. However, adolescent drinking behaviors in supervised situations had weak correlations with their belif systems and deviant behaviors. 3. Adolescent drinking levels were remarkably influenced by drinking behaviors in unsupervised situations. Because it is difficult to control actual adolescent drinking behaviors in unsupervised situations, it is important to fortify their belief system with continuous education programs.

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소형 열병합 발전기 계통연계 운전시의 적용 보호지침 개선 제안 (A case Study for Protection Relay System of small Cogeneration intertie)

  • 윤갑구;김경식;현대원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.227-230
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    • 2004
  • The Co-Gen System which maximize energy efficiency was installed at the industrial plants at the initial stage. However Small Scale Co-Gen System was expanded even to the general end-users such as housing and building owing to ESCO business recently. For this SSC, inter-connected operation to the utility is desirable due to voltage and frequency fluctuation following to unbalance between power output and load. Then voltage unbalance with utility system, frequency, increase of short circuit capacity, reclosing, and ALTS etc. should be fully considered for the inter-connected operation. Voltage variation, protection coordination, Co-Generators single running, and short circuit capacity should also be solved. For Con-Gen users, the several protection relays are recommended to install at the user's main incoming panel by the guide lines and/or instructions of the interconnected utility Then user's main CB(Circuit Breaker) have the chance to be tripped by some of this recommended relays and users have to undergo the unexpected blackout. So the circuit breaker trip schemes targeted to trip with these protection relays are reconsidered and the study result is hereunder proposed.

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IEEE 929-2000 단독운전 시험조건 하에서 단상 계통연계형 PV 시스템의 Anti-Islanding을 위한 RPV 방식 및 AFD방식의 해석 및 설계 (An Analysis and Design of RPV and AFD Method for Anti-Islanding of Single-Phase UIPV System under The Test Condition Recommended by IEEE 929-2000)

  • 김흥성;김한구;최규하;김재철;최영호
    • 전력전자학회논문지
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    • 제12권1호
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    • pp.37-49
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    • 2007
  • 계통연계형 PV 시스템의 중요한 보호기능인 단독운전 검출기능은 시스템의 안전성 및 전기적 안정성 측면에서 매우 중요하다. 단독운전 검출기법으로는 크게 수동적 방식과 능동적 방식으로 분류되는 다양한 기법들이 있다. 본 연구에서는 IEEE 929-2000에서 제시하는 단독운전 시험조건 하에서 현재 널리 사용되는 능동적 방식 중 무효전력 변동 방식(RPV method)과 능동적 주파수 변동 방식(AFD method)을 채용한 시스템의 연계점에서 주파수 변동 특성을 해석하였다. 그리고 해석결과를 바탕으로 RPV 방식 및 AFD 방식의 설계법을 제시하였다. EMTP를 이용한 시스템 시뮬레이션을 통하여 제안된 해석 및 설계법의 타당성 및 유효성을 검증하였다.

전화통신 서비스품질정보시스템 설계에 관한 연구 (The Design of Service Quality Information Systems for Telephone Communication)

  • 염창선
    • 품질경영학회지
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    • 제29권3호
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    • pp.97-108
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    • 2001
  • The information system for measuring and analyzing service quality of telephone network is designed on the service quality scheme recommended by ITU(International Telecommunication Union) in this study. The information system is composed of the equipments which measure service quality and the systems which analyze the measured data. The schedule algorithm for effectively operating measurement equipments which are located over public switched telephone network is proposed. The functions of the Information system are Introduced. The information system improves the service quality effectively.

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Association between adherence to the Korean Food Guidance System and the risk of metabolic abnormalities in Koreans

  • Jung, Hyun-Ju;Han, Sung-Nim;Song, Su-Jin;Paik, Hee-Young;Baik, Hyun-Wook;Joung, Hyo-Jee
    • Nutrition Research and Practice
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    • 제5권6호
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    • pp.560-568
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    • 2011
  • Consumption of a diet consistent with dietary guidelines is believed to have a beneficial effect on the prevention of chronic diseases and the promotion of general health. This study was conducted to explore the relationship between adherence to the Korean Food Guidance System (KFGS), which was based on the 2010 revised KDRIs, and the risk of metabolic abnormalities. Five hundred and ninety-six Korean adults between 30 and 59 years of age were recruited by advertisement to the Bundang Jesaeng General Hospital (BJGH), and those not taking regular medications and without diagnoses of fulminant disease were included. Data were collected on anthropometric measurements, diagnostic parameters for metabolic syndrome (MetS), and 3-day dietary intakes from individuals in the study. The number of servings consumed from each food group was compared to the KFGS recommended servings for each of the 6 food groups. Poor adherence to the recommendations for servings of milk and dairy products (OR: 2.038, 1.128-3.682) was associated with a higher risk of MetS, and poor adherence to the guidelines for fruit consumption (OR: 1.849, 1.027-3.329) was associated with a higher risk for the existence an elevated waist circumference. Conversely, the consumption of meat, fish, eggs, and beans above the recommended number of servings was associated with a lower risk of having an elevated waist circumference (OR: 0.523, 0.288-0.950), and the consumption of vegetables above the recommended number of servings was associated with a reduced risk of having elevated fasting glucose (OR: 0.533, 0.298-0.954). These results suggest that adherence to the KFGS guidelines helps to prevent the development of MetS, but this association needs to be confirmed by prospective studies.

지형 수치지도를 활용한 표준분석구역 설정 및 토지이용 정보체계의 구축방법론 (A Study on the Concept and Methodology of the Zone-Based Landuse Information system Using Digital Maps; A Case of Pohang City)

  • 구자훈
    • Spatial Information Research
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    • 제6권2호
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    • pp.169-182
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    • 1998
  • 구역중심 토지정보시스템은 도시계획 행정가와 연구자에게 중요한 정보시스템 중의 하나이다. 이 연구는 구역중심 토지정보시스템을 구축하기 위해서 필요한 계획분석구역의 개념 정립과 수치지도를 활용한 구축방법론에 관한 연구이다. 구역중심 토지정보시스템을 구축하기 위한 기초작업으로서, 본 연구에서는 계획분석구역의 개념을 설정하고, 이를 포항시에 적용하여 여러 가지 유형의 구역을 구분해 보았다. 또 기존의 통계연보나 행정이 가지고 있는 통계자료 중에서 구역중심 토지정보시스템을 구축시 필요한 정보의 종류 및 출처 등을 구체적으로 살펴보았다. 본 연구에서는 수치지도를 활용하여 GIS를 구축하기 위해서 수치지도가 가지고 있는 지형정보에 관한 730여개의 세분류 항목 중에서 구역중심 토지정보시스템에 필요하게 될 84개의 세분류 항목을 선정해보기도 하고, 좀 더 세부적인 토지정보를 위해서 필요한 약 250여개의 세분류 항목이 필요함도 지적되었다. 이 연구의 의의는 토지정보시스템에 관한 기존의 많은 연구가 필지중심 토지정보시스템에 관한 내용이었는데 반하여, 구역중심 토지정보시스템의 구축 필요성을 제기하고 또, 구역중심 시스템 구축을 위해서 필요한 기본적인 개념과 방법론에 관한 구체적인 방향을 제시하였다는 데 있다.

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설명 가능한 개인화 영화 추천 서비스를 위한 딥러닝 기반 텍스트 요약 모델 (Deep Learning-based Text Summarization Model for Explainable Personalized Movie Recommendation Service)

  • 진요요;강경모;김재경
    • 한국IT서비스학회지
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    • 제21권2호
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    • pp.109-126
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    • 2022
  • The number and variety of products and services offered by companies have increased dramatically, providing customers with more choices to meet their needs. As a solution to this information overload problem, the provision of tailored services to individuals has become increasingly important, and the personalized recommender systems have been widely studied and used in both academia and industry. Existing recommender systems face important problems in practical applications. The most important problem is that it cannot clearly explain why it recommends these products. In recent years, some researchers have found that the explanation of recommender systems may be very useful. As a result, users are generally increasing conversion rates, satisfaction, and trust in the recommender system if it is explained why those particular items are recommended. Therefore, this study presents a methodology of providing an explanatory function of a recommender system using a review text left by a user. The basic idea is not to use all of the user's reviews, but to provide them in a summarized form using only reviews left by similar users or neighbors involved in recommending the item as an explanation when providing the recommended item to the user. To achieve this research goal, this study aims to provide a product recommendation list using user-based collaborative filtering techniques, combine reviews left by neighboring users with each product to build a model that combines text summary methods among deep learning-based natural language processing methods. Using the IMDb movie database, text reviews of all target user neighbors' movies are collected and summarized to present descriptions of recommended movies. There are several text summary methods, but this study aims to evaluate whether the review summary is well performed by training the Sequence-to-sequence+attention model, which is a representative generation summary method, and the BertSum model, which is an extraction summary model.

自然景觀水系의 體系樹立을 위한 基礎硏究(I) -美國의 自然景觀水系制度 紹介 및 國內適用 事例硏究- (A Study on the Wild and Scenic Rivers System(I) -American Experience, and Suggestions for System Building in Korea-)

  • 안동만;안성로;진영환
    • 한국조경학회지
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    • 제18권3호통권39호
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    • pp.57-70
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    • 1990
  • This study is on system building and model case study to establish a new framework of "The Wild and Scenic Rivers System" and to apply this to Korean rivers. The Wild and Scenic Rivers System of the U. S. , which had become law in 1968 for establishing wild scenic and recreational river areas, was investigated. The techniques of two American case studies about the National Wild and Scenic Rivers System designation were investigated and synthesized, and study process was adjusted to Korean river system. Additionally, pilot study was carried out by the method and results were as follows : 1) In the American Wild and Scenic Rivers System, each river was evaluated based on eligibility criteria for designation, such as remarkable scenic, recreational, fish and wildlife, cultural or other ecological values. Segmented river areas were classified into three or four grades and management plans were prepared accordingly. 2) The management of rivers in Korea has emphasized on the flood control and water resources management up to the present, and now takes a growing interest in water quality. But it has been concerned very little with wild and scenic resources conservation of river corridors. It is strongly recommended to build Wild and Scenic Rivers System in Korea for rational management and conservation of the valuable natural resource. 3) Suggested evaluation criteria for the Korean Wild and Scenic Rivers System were wildness, wildlife and plants, hydrology, scenic quality, and historical and cultural resources. The river areas may be graded into four : Positive conservation area(I), Negative conservation area(II), Negative development area(III), Positive development area(IV). Management guidelines were proposed for each grade. 4) To test the applicability of the approach, one of the major tributary of the Han-River was selected for pilot study. The result showed that the evaluation and grading system worked well. Finally, it is recommended to incorporate the Wild and Scenic Rivers System into Korean national park system, and to amend the Korean National Park Act to enable this.

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최적부하제한방식의 결정과 운용에 관한 연구 (A Study on the Determination and Application of the Optimum Load Shedding Schemes)

  • Song, Kil-Yeong
    • 대한전기학회논문지
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    • 제34권1호
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    • pp.29-37
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    • 1985
  • During Severe emergencies which result in the case of outage of large generator units, an automatic underfrequency protection scheme can prevent the system frequency from decaying and improve the system stability. This paper presents methods and results of a study on the optimum load shedding scheme which covering as follows. 1) Detail representation of governor model 2) Determination of optimum load shedding amount 3) Selection of action time settings of UFR 4) Comparsson of load shedding programs By this study, the optimum system operating method was recommended for reliable operation of power system.

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