• 제목/요약/키워드: frequency plan

검색결과 846건 처리시간 0.026초

$SF_6$ 가스중 방전진전과정에 따른 방사전자파의 주파수 스펙트럼 분포 특성 (The Frequency Spectrum Characteristics of Radiated Electromagnetic Wave by the Process of Discharge Progress in $SF_6$)

  • 박광서;김해준;최병주;전영주;이동헌;이광식;이동인
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 C
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    • pp.1747-1749
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    • 2001
  • This paper simulated discharge progress and partial discharge using needle-plan electrodes system in $SF_6$, studied the distribution of frequency spectrum of the radiated electromagnetic waves using biconical antenna and spectrum analyzer. From results of this study, a method was introduced for measurement and analysis of the radiated electromagnetic waves in accordance with discharge progress in $SF_6$. Besides, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting partial discharge and estimating discharge progress in $SF_6$ can be possible.

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국가적 관점에서 각 용도별 ESS 적정용량 산정을 위한 투자수리모델 수립에 관한 연구 (Study on Establishing Investment Mathematical Models for Each Application ESS Optimal Capacity in Nationwide Perspective)

  • 김정훈;윤석민
    • 전기학회논문지
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    • 제65권6호
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    • pp.979-986
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    • 2016
  • At present, electric power industry around the world are being gradually changed to a new paradigm, such as electrical energy storage system, the wireless power transmission. Demand for ESS, the core technology of the new paradigm, has been growing worldwide. However, it is essential to estimate the optimal capacity of ESS facilities for frequency regulation because the benefit would be saturated in accordance with the investment moment and the increase of total invested capacity of ESS facilities. Hence, in this paper, the annual optimal mathematical investment model is proposed to estimate the optimal capacity and to establish investment plan of ESS facility for frequency regulation. The optimal mathematical investment model is newly established for each season, because the construction period is short and the operation effect for the load by seasons is different unlike previous the mathematical investment model. Additionally, the marginal operating cost is found by new mathematical operation model considering no-load cost and start-up cost as step functions improving the previous mathematical operation model. ESS optimal capacity is established by use value in use iterative methods. In this case, ESS facilities cost is used in terms of the value of the beginning of the year.

Children's Bent Wooden Chair Design Using High Frequency Heat Molding Technique - Focused on Change of Kindergarten Environment -

  • Ryu, Eun-Seok;Choi, Kyung-Ran;Sung, Yun-Jung
    • 한국가구학회지
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    • 제22권3호
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    • pp.230-238
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    • 2011
  • Consumers' expenditure is getting larger on children due to their parents' compensation for increase of double-income family life and decrease of birth rate caused by high economic growth. Increase of demand on children items in the market leads the necessity of development of furniture for children. This study is aimed to design children chairs that meet the environment for children. In this study, the age of children is defined to be 5~7 years old. In order to investigate what causes environment change, this study covers roughly change of environment, change of learning program and use of environment-friendly material. In such scope, we drew out the factors that the chairs for children shall be equipped with. Case studies were done through such drawn factors. The scope of the furniture for children is limited to the chairs for children among the ones made in either Korea or overseas. As a result, we could draw out such keyword of the furniture as storage, mobility, environment-friendly, object style image, preferred color, functionality and safety, based on which we could plan the design and make the final result through high frequency round molding manufacturing process.

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대기중 방전진전에 따른 방사전자파의 주파수 스펙트럼 특성 (The Characteristic of Frequency Spectrum of Electromagnetic Waves Radiated from Discharge in Air)

  • 박광서;이상훈;주재현;최병주;이광식;이동인
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 E
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    • pp.2245-2247
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    • 1999
  • Insulation diagnosis techniques of power equipments for the stable power supply and prevention from accidents are of high importance. Diagnosis techniques is able to prevent from large accidents before they happen by finding signs of the accidents. From this point of view, this paper simulated discharge progress and partial discharge using needle-plan electrode system in air, studied the distribution of frequency spectrum of the radiated electromagnetic waves using biconical antenna and spectrum analyzer. From results of this study. the new method was introduced for measurement and analyzation of the radiated electromagnetic waves in accordance with discharge progress in air. Besides, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting partial discharge and estimating discharge progress were possible.

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석유화학공장에서의 한국형 위험기반검사에 의한 화학설비의 안정성 평가 (Analysis of Safety of the Chemical Facilities by Korea Risk Based-Inspection in the Petrochemical Plant)

  • 김태옥;이헌창;신평식;최병남;조지훈;최병용;박성후;김형근
    • 한국안전학회지
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    • 제22권6호
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    • pp.35-40
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    • 2007
  • As a way of improving the safety of the chemical facilities, the risk based-inspection(RBI) was executed for the facilities of the applied petrochemical plant using KS-RBI Ver. 3.0 program developed based on the API-581 based resource document(BRD). From an evaluation result of KS-RBI program, we could find the evaluation of the process safety management(PSM) for the applied plant, risk of the applied process, risk of static facilities and pipes, and the demage mechanism of the facilities. Also, we could suggest a proper inspection plan(frequency and method of inspection) using the calculated risk and the status of the facilities. Therefore, the applied plant could be achieved a reduced inspection cost by an extension of inspection frequency, improved productivity, improved reliability of the facilities, and a computerized history management.

A Study on the Noise Characteristics of noise occurred when medical examination in dental clinic

  • Ji, Dong-Ha;Lee, Yong-Gyoo
    • 한국컴퓨터정보학회논문지
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    • 제23권12호
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    • pp.163-170
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    • 2018
  • This study was conducted to investigate the effects of noise from dental clinics on workers and to establish a reduction plan. The noise generated by the treatment instrument(Ultrasonic scaler, Hand piece, 3-way syringe, Suction, Compressor) was measured in order to determine the characteristics(level, frequency) of the noise during medical treatment(Oral prophylaxis, Conservation treatment, Prosthesis treatment, Implant Scaling, Tooth eliminating). We also assessed the noise levels in dental clinic using evaluation indicators such as NR-curves and NRN. The results of the analysis showed that the noise generated during the treatment was 85dB(A) ~ 70dB(A) and that the high frequency component was dominant, which would affect the workers working at the dental clinic. The NR-curve analysis showed NR-67 to NR-83 and the high frequency components of 4kHz to 8kHz were predominant and far exceeded noise levels in the workplace. To minimize the noise damage of workers and to provide high quality medical service, it is necessary to establish countermeasures such as wearing a soundproof and periodic hearing tests.

Review on ICF-related Research Trends in Korean Clinical Field

  • Song, Ju-Min
    • 대한물리의학회지
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    • 제16권4호
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    • pp.33-44
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    • 2021
  • PURPOSE: This study analyzed the research trends related to the International Classification of Functioning, Disability, and Health (ICF) to suggest an ICF utilization plan in the Korean clinical field. METHODS: In the RISS, KISS, NSDL, and PubMed databases, papers published between 2016 and July 2021 were collected by applying the search terms, 'ICF', 'international classification of functioning, disability and health', 'clinic', 'patient', and 'diagno'. The 44 papers selected were classified according to the analysis criteria, and the frequency and percentage were calculated. RESULTS: In domestic clinical trials, the frequency of ICF-related studies was in the order of physical therapy (n = 19) and occupational therapy (n = 14). The frequency of each study subject was observed in the order of studies related to a specific disease (n = 34) and prior studies (n = 7). The research topics were in the order of studies using ICF as a measurement tool (n = 21) and case studies with patients with specific diseases (n = 11). There were 18 studies using ICF codes and 14 papers applying the ICF domains. CONCLUSION: Over the last five years, ICF-related research in the domestic clinical field targeted patients with more diverse diseases in more expertise fields. Research for the unification of terms should be conducted for communication among various experts in clinical practice. To promote the use of ICF in the clinical field, it will be necessary to conduct research, such as the unification of terms, standardized education, development of ICF casebook, and development of ICF coding programs and guidelines.

서울시 둔촌동 습지 생태계보전지역 모니터링 및 생태적 복원구상 (The Monitoring and Ecological Restoration Concept of Ecosystem Conservation Area in Dunchon, Seoul)

  • 한봉호;김정호;홍석환
    • 한국환경생태학회지
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    • 제17권3호
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    • pp.242-257
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    • 2003
  • 본 연구는 생태계보전지역인 둔촌동습지의 모니터링을 통한 생태적 복원 및 보전계획을 수립하기 위해 실시되었다. 모니터링 기준으로는 항목, 방법, 시기, 횟수 등을 설정하였다. 모니터링 기준에 따라 조사한 결과 식물생태분야에서 대상지내 식물종은 총 39과 116종 19변종 1품종으로 총 132종류가 출현하였고 이중 자생종은 85종, 외래종은 47종이었다. 월별(4∼9월) 현존식생 모니터링 결과 습지성 초본식물군락 세력이 증가추세이었고 특히 고마리군락의 세력이 왕성해졌다. 아울러 기존 경작지를 중심으로 천이초기식물과 귀화식물의 출현빈도가 높았다. 동물생태분야에서 야생조류는 34종 378개체, 양서류는 4종 5개체, 곤충류는 11목 52과 153종이 조사되었다. 무기환경분야에서는 지하수위. 수질. 토양특성을 분석하였는데 이중 지하수위는 0.0∼89.0cm이었고 토양에서는 Ca++의 함량이 2.18∼13.73cmol/kg로 나타났다. 모니터링 결과를 바탕으로 한 연구대상지 생태적 복원구상을 습지생태계 복원구상. 용출지 복원구상. 산림생태계 복원구상으로 구분하여 기본방향과 각 공간별 세부계획을 제시하였다. 습지생태계 복원구상에서는 기존 습지지역의 보전과 경작지로 활용되던 습지지역의 복원구상을 수립하였으며, 용출지복원구상에서는 용출지 및 진입부의 복원을 수립하였고 산림생태계 복원구상에서는 건조성 산림 생태계와 습지성산림생태계의 복원 및 주연부지역의 야생조류 서식처 계획을 수립하였다.

식생활관리 실태에 관한 연구 -서울시내 주부를 중심으로- (A Study on the Survey of the Meal Management)

  • 유영상
    • 대한가정학회지
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    • 제18권1호
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    • pp.53-66
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    • 1980
  • One of the most pressing problems of the day in our household economy is the scientific improvement of meal management, which has direct bearings on the efficiency of housewives, domestic economy, and health care for the whole family. The concern of this paper is to investigate the current meal management situation in which more than three hundred housewives in Seoul find themselves, and to propose a tentative plan for its improvement. The result of the investigation is summarized as follows : 1) The number of families with old-fashioned kitchens forms a percentage of 30.3 ; only 4.3 percent of them have waterworks and drainage system. 2) The number of families equipped with cooking machines and utensils constitutes 51.2 percent ; that of those without cooking machines reaches the high percentage of 92.8. 3) The expense for daily meals amounts to 37.9 percent of the whole domestic expenses. the number of those who prepare daily meals without any planning comprises 78 percent. It is from habit that 60.5 percent of them make no workable plan for their meals. 4) The frequency of housewives doing daily marketing is comparatively high. 5) The time spent in preparing and clearing the table is 280.4 minutes a day on the average. 6) In preparing daily meals the low income bracket tends to keep expense as low as possible, while the high income bracket is chiefly concerned with taste. 7) The frequency of home cooking is on the increase as the housewives grow older, especially in the large families with housemaids. 8) In most cases housewives do the cooking for themselves; the high income brackets have housemaids do the cooking. The number of husbands who help their wives do kitchen work a small percentage of 10-14. 9) The simplification of kitchen work presupposes the simplification of the daily cooking, the improvement of the structure and equipment of the kitchen, and a good help of the whole family.

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일본의 전파정책 및 이용전략 연구 (A Study on Spectrum Policy and Usage Strategies in Japan)

  • 박덕규
    • 한국전자파학회논문지
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    • 제23권8호
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    • pp.861-877
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    • 2012
  • 최근 일본 총무성에서는 미래 전파의 이용을 통하여 일본이 직면하고 있는 사회적 문제를 해결함과 동시에, 전파를 이용한 기술 발전을 기반으로 2010년대의 효과적인 전파 사용을 위한 정책을 발표하였다. 또한, 2010년 8월에는 white space의 제도화를 촉진하기 위한 "White Space 특구" 설립을 제안하였으며, 제안된 내용의 실현을 위한 선행 모델이 발표되었다. 2010년 12월에는 무선 광대역 실현을 목표로 하는 주파수 재편에 대한 Action Plan이 발표되었다. 본 논문에서는 일본에서 발표된 전파 정책의 추진 배경, 주요 전략과 정책 방향을 검토하고, 2010년대에 제공되는 서비스와 시스템의 실현 이미지에 대한 내용을 분석하였다. 현재 우리나라에서는 방송통신위원회가 중심이 되어 "함께 누리는 스마트 코리아"를 비전으로 미래의 전파 정책인 "모바일 광개토 플랜"을 발표하였으며, 현재 모바일 이외의 분야에 대한 전파 정책을 수립하고 있는 중이다. 여기에서 제시한 내용은 국내 전파 정책 수립과 전파의 효율적인 사용과 확대에 기여할 것이다.