• 제목, 요약, 키워드: Expected efficiency

검색결과 2,321건 처리시간 0.051초

HRT 변경에 따른 호기성 그래뉼 슬러지의 오염원 제거효율에 미치는 영향 (Effects of Different Hydraulic Retention Times on Contaminant Removal Efficiency Using Aerobic Granular Sludge)

  • 김현구;안대희
    • Journal of Environmental Science International
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    • v.28 no.8
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    • pp.669-676
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    • 2019
  • The purpose of this study was to evaluate the effects of different Hydraulic Retention Times (HRTs) on the contaminant removal efficiency using Aerobic Granular Sludge (AGS). A laboratory-scale experiment was performed using a sequencing batch reactor, and the Chemical Oxygen Demand (COD), nitrogen, orthophosphate removal efficiency, AGS/MLSS ratio, and precipitability in accordance with the HRT were evaluated. As a result, the COD removal efficiency was not significantly different with the reduction in HRT, and at a HRT of 6 h, the removal rate was slightly increased owing to the increase in organic loading rate. The nitrogen removal efficiency was improved by injection of influent division at a HRT of 6 h. As the HRT decreased, the MLSS and AGS tended to increase, and the sludge volume index finally decreased to 50 mL/g. In addition, the size of the AGS gradually increased to about 1.0 mm. Therefore, the control of HRT provides favorable conditions for the stable formation of AGS, and is expected to improve the contaminant removal efficiency with the selection of a proper operation strategy.

Doherty 전력증폭기의 선형성 개선과 효율 보상 방안에 관한 연구 (A Study on Improvement of Linearity and Efficiency Compensation in a Doherty Power Amplifier)

  • 장정석;도지훈;윤호석;김대희
    • 한국ITS학회 논문지
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    • v.8 no.2
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    • pp.75-82
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    • 2009
  • 본 논문에서는 Doherty 전력 증폭기의 선형성을 증가시키는 mechanism을 이용하여 선형성을 증가시키고, 선형성 개선으로 인한 효율 감소를 보상할 수 있는 방법을 제안하였다. 또한 이를 검증하기 위하여 제안된 방법으로 20W급 전력 증폭기를 설계 및 제작하였다. 제작된 class-F를 이용한 3-way 증폭기는 2-way 증폭기보다 선형성이 약 10dBc개선되었으며, 효율은 1.5% 가량 개선되었다. 또한 3-way 증폭기와 비교하였을 때, 선형 특성은 비슷하였으나, 효율 특성은 약 3.5% 개선되었다. 본 논문에서 제안한 F급 바이어스를 이용한 3-way Doherty 전력 증폭기는 선형성 및 효율 향상에 적합함을 확인할 수 있으며, 향후 다양한 무선 통신 시스템의 전력 증폭기에 적용되리라 기대한다.

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耳鳴의 形態와 治療效率에 對한 臨床的 分析 (A Clinical analysis on the Treatment efficiency of Tinnitus by Types of bianzheng(辨證))

  • 김경준
    • 한방안이비인후피부과학회지
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    • v.12 no.2
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    • pp.182-188
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    • 1999
  • Tinnitus is a symptom frequently encountered in the E.N.T. clinic and variously described as buzzing, ringing and thumping sound, etc., but the cause, pathogenesis, specific treatment remains to be established through close investigation. In fact, it is not easy to evaluate the treatment efficiency of tinnitus reasonably. However, in this study. we clinically investigated 47 patients who visited E.N.T. department of Kyung Won University Hospital from May. 1996 to May. 1999 and belonged to specific bianzheng(辨證) types of tinnitus classified by bianzheng(辨證), a kind of diagnostic method in order to estimate efficiency of the treatment and give aids to establishing more effective and recognizable treatment method. The result is as follows: 1) In bianzheng(辨證) types of tinnitus, Piweixuruo(脾胃虛弱) was most frequently found, in descending order, Shenjingkuisun(腎精虧損), Ganhuoshangra(肝火上擾), Tanhuoyongjie(痰火壅結). 2) In the treatment efficiency, the type of Piweixuruo(脾胃虛弱) showed the highest, in descending order, Ganhuoshangrao(肝火上擾), Tanhuoyongjie(痰火壅結) and Shenjingkuisun(腎精虧損). 3) The treatment efficiency is shown higher in patients with tinnitus included in other sysmptoms than those with a simple symptom of tinnitus. especially in case of tinnitus accompanied by vertigo, we could get much higher treatment efficiency more than we had expected.

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Classification Index and Grade Levels for Energy Efficiency Classification of Agricultural Heaters in Korea

  • Shin, Chang Seop;Jang, Ji Hoon;Kim, Young Tae;Kim, Kyeong Uk
    • Journal of Biosystems Engineering
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    • v.38 no.4
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    • pp.264-269
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    • 2013
  • Purpose: This study was carried out to develop a classification index and grade levels to rate agricultural heaters for energy efficiency classification. Methods: The classification index was developed mainly by taking simplicity of calculation and easy access to relevant data into consideration. The grade levels were developed on the basis of a 5-grade classification system in which graded heaters are to be normally distributed over the grades. The value of each grade level were determined in terms of the classification index values calculated using the published performance data of agricultural heaters tested at the FACT in Korea over the past 12 years. Results: The thermal efficiency of agricultural heaters based on the enthalpy method was proposed as a reasonable classification index. The grade levels were proposed in equation form for three types of agricultural heaters: fossil fuel heaters, wood pellet heaters and wood pellet boilers. A reasonable energy efficiency classification of agricultural heaters could be performed using the proposed classification index and grade levels. Conclusions: It is expected that energy saving programs will be extended to agricultural machines in the near future. The classification index and grade levels to rate agricultural heaters for energy efficiency classification were developed and proposed for such near future to come.

20kW급 폐열회수 시스템 공정 설계에 관한 연구 (A Study on the Engineering Design for 20kW-Grade Waste Gas Heat Recovery)

  • 김경수;방세경;정은익;이중섭
    • 한국기계가공학회지
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    • v.17 no.4
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    • pp.91-96
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    • 2018
  • This study is collects design data through the process design of the organic Rankine cycle, which can produce 20kW of electric power through the recovery of waste heat. In this study, the simulation was conducted by using APSEN HYSYS in order to make the model for the process design of the 20kW class waste heat recovery system. For the thermodynamic model, the test was conducted with hot water as the heat source, with the water steam used as the cooling water for the cooler and the refrigerant R245fa in the cycle. In Case 1 and Case 2, it was expected and found that the cycle efficiency was 10.6% and that 36.86kw was produced, considering the margin of 84% of 20kW. In Case 3 and Case 4, it was expected and found from the simulation that the cycle efficiency was 12% and that 30.0kw was produced, considering the margin of 84% of 20kW.

호텔레스토랑의 메뉴선택요인에 대한 실증적 연구 (이태리레스토랑을 중심으로) (A study on management efficiency for the Hotel & Restaurant Banquet Service.)

  • 류경민
    • 한국조리학회지
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    • v.6 no.2
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    • pp.227-246
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    • 2000
  • A few years ago, hotel service was not usual to the people very much but it's normally usual only for the higher-grade people. However now a days, it's expected that hotel service is universal one with changing of life style. It's rising to use hotel with being on the increasing of the international alternating so that the banquet service can be expected as the much more important service point of hotel. At the same time there are much more chances to participate in the personal parties and meetings. That means the demand is increasing than before. So every hotels are trying to promote the quality of the service, make renovation and suggest the specially distinguished service in comparison with the other hotels so as to get the banquet customers. Actually the sales amount from the banquet in the hotel can be said the biggest one in these days. That's why we cannot help thinking it the very important point at the hotel service. So we would 1ike to suggest the best way of managing hotel banquet service more efficiency and would like to find out how we can serve the higher quality service to the banquet customers in order them to make feel more satisfactory.

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3D CAD System에 의한 안동포의류제품 패턴설계 (Andongpo Apparel Pattern Design Connected with the 3D Apparel CAD System)

  • 김희숙
    • 한국의류산업학회지
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    • v.11 no.1
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    • pp.112-120
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    • 2009
  • The purpose of this study is to develop Andongpo apparel pattern design connected with the Apparel CAD system. It includes pattern making, grading, marking program. In this study, it will be able to make apparel pattern quickly and accurately by using Apparel CAD system. The results were as following : Computerization of the pattern making process is expected to provide higher accuracy and efficiency in apparel pattern making for narrow and expensive Andongpo. ESMOD pattern making method was selected as basic pattern. Tailored jacket patterns were developed for Andongpo. Refer to and . The jacket patterns developed is automatically depicted by inputting consumer's body size. Tailored jacket patterns for Andongpo were marked by using marking program in Apparel CAD system. The efficiency of marking appeared of 70% or more in Andongpo jacket patterns. This results is showed it has an effect on narrow and expensive Andongpo. 3tailored jacket patterns will be able to make a simulation by 3D Apparel CAD system. The results of this study is expected to provide higher consumer's satisfaction and internet brand launching. In addition, encouraging majority of the young to participate in using CAD program for Andongpo is regarded as beneficial for the reinforcement of competitiveness of traditional clothing business.

공공 도로건설사업에서의 원격 현장모니터링 체계 구축에 관한 연구 (A Study on Development of Remote Site Monitoring System in Public Road Construction Projects)

  • 옥현
    • 한국도로학회논문집
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    • v.14 no.6
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    • pp.57-65
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    • 2012
  • PURPOSES : Efficiency Improvement of a public road construction project management work using the development of a real-time remote site monitoring system METHODS : In this study, we developed the remote site monitoring system using a web camera for road construction projects in the RCMA(Regional Construction Management Administration). We can be monitored a construction progress and a weak point of the situation in real time using this. To achieve this, we tested about 10 road construction projects ordered by RCMA. Then, we verified a applicability for the site monitoring system in future. RESULTS : Take advantage of the remote site monitoring system consists of the Construction CALS System, one of the business systems used in the part of the MLTM(Ministry of Land, Transport and Maritime Affairs) institution-agencies. Was configured to be served through the "Construction CALS System" of "Construction Management System(Contractors)" and the "Construction CALS Portal System". Through this, Benefit analysis through a pilot application of the 10 road construction sites and developing considerations and "Guide for visual information processing equipment installation-operating in construction sites"are presented. CONCLUSIONS : Through the establishment of remote site monitoring system can improve the efficiency of construction management services. In addition, Various disasters and calamities, accidents and illegal construction will be prevented in advance is expected. This is expected to further improve the quality of the facilities.

몬테카를로 시뮬레이션을 이용한 직접부하제어의 제어지원금 산정 (Determination of Incentive Level of Direct Load Control using Monte Carlo Simulation with Variance Reduction Technique)

  • 정윤원;박종배;신중린;채명석
    • 대한전기학회:학술대회논문집
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    • pp.666-670
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    • 2004
  • This paper presents a new approach for determining an accurate incentive levels of Direct Load Control (DLC) program using sequential Monte Carlo Simulation (MCS) techniques. The economic analysis of DLC resources needs to identify the hourly-by-hourly expected energy-not-served resulting from the random outage characteristics of generators as well as to reflect the availability and duration of DLC resources, which results the computational explosion. Therefore, the conventional methods are based on the scenario approaches to reduce the computation time as well as to avoid the complexity of economic studies. In this paper, we have developed a new technique based on the sequential MCS to evaluate the required expected load control amount in each hour and to decide the incentive level satisfying the economic constraints. And also the proposed approach has been considered multi-state as well as two-state of the generating units. In addition, we have applied the variance reduction technique to enhance the efficiency of the simulation. To show the efficiency and effectiveness of the suggested method the numerical studies have been performed for the modified IEEE reliability test system.

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딸림자료의 멀티미디어 데이터베이스 구축을 통한 이용 효율 제고에 관한 연구 (Elevating Utilization Efficiency through the Multimedia Database Construction of Accompanying Materials)

  • 이주현;이응봉
    • 정보관리연구
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    • v.35 no.2
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    • pp.41-55
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    • 2004
  • 본 연구에서는 딸림자료 중 특히, 오디오 테이프 형태의 자료를 디지털화하여 멀티미디어 데이터베이스를 구축함으로써 이용자의 이용편의와 자료관리의 효율성을 제고하는 것에 대한 방안에 대해 논의하고자 한다. 이를 위해 본고에서는 딸림자료의 관리현황, 오디오 데이터 포맷의 종류, 데이터 포맷변환, 관리 및 이용방안 등을 살펴보았다. 또한, 딸림자료의 멀티미디어 데이터베이스 구축을 통한 기대효과 및 문제점을 제시하였다.