• 제목/요약/키워드: economically feasible

검색결과 217건 처리시간 0.024초

정전압 DC 급전시스템에서의 회생전력 (Regenerated Power in Fixed voltage DC Electric Power Supply System)

  • 정상기;이병송;정락교;박성혁;김국진
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2001년도 추계학술대회 논문집
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    • pp.343-349
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    • 2001
  • In this study we examined the method to estimate numerically the amount of the regenerated power and the excess regenerated power produced in the DC electric power supply system for the urban light rail transit system. And their economic feasibilities are also studied. For this study DC electric power supply system is simulated and the numerical analysis of the regenerated power and the excess regenerated power are conducted. The study result on the sample system shows that the facility to consume the excess regenerated power or the inverting equipment to reuse the excess regenerated power in the electric substation is feasible economically.

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바다숲 조성사업의 경제적 효과 분석 : 강릉 주문진 바다숲 조성사업을 대상으로 (An Economic Analysis of the Marine Afforestation Project in Gangneung Region, Republic of Korea)

  • 박경일;홍혜수;김도훈
    • 수산해양교육연구
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    • 제28권3호
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    • pp.727-737
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    • 2016
  • This study is aimed to analyze the economic effectiveness (direct fishing income effect) of the marine afforestation project in Gangneung region. Based on the surveyed data, the production values and costs of the marine afforestation project are estimated and compared to determine the economic validity of the marine afforestation project. Results show that the B/C ratio, as an indicator of economic evaluation, is 1.30 with an interest rate of 5.5%, indicating that the marine afforestation project in Gangneung region would be economically feasible under the current production and market conditions. However, it is expected that the economic effectiveness would be increased when considering benefits of recreational fishing and greenhouse gas reduction from the marine afforestation project.

우리나라 생강 뿌리썩음병의 연구현황과 향후과제 (Review of Researches on Rhizome Rot of Ginger and Future Tasks for Its Management in Korea)

  • 김충회
    • 식물병연구
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    • 제10권2호
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    • pp.87-93
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    • 2004
  • Rhizome rot of ginger, caused by Pythium myriotylum, a major limiting factor for its production, has occurred annually, but become severe, especially in hot and humid years with frequent rainfalls in Korea. Most studies on rhizome rot have been carried out since 1980s in the National Institute of Agricultural Sciences and Technology, Honam Crop Experimental Station and Choongnam Provincial Rural Development Administration. Many aspects of rhizome rot, such as survey of the disease incidence, taxonomy, pathogenicity and physiology of pathogen, and ecology of soilborne inocula have been studied in the researches. However, intensive studies have been concentrated on management technologies of the disease including seed-rhizome disinfection, soil sterilization, evaluation of cultivar resistance, and fungicide application, and most developed technologies have been used in commercial farmings. In future, development of resistant varieties and simple soil disinfection technologies applicable in Korean condition and economically feasible fungicide application technology have to be developed for better management.

곤돌라형 외벽 유지관리 로봇의 이동/작업 메커니즘 및 플랫폼 개발 (Development of Gondola-type Building Management Robot Platform and Mechanism for Moving/Tasking on Building Outer-wall)

  • 함영복;박성재
    • 한국정밀공학회지
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    • 제30권4호
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    • pp.375-382
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    • 2013
  • Down through the years, human needs and desires have required a robot system to work at hazardous environments instead. Current painting task is costly and laborious, and it exposes workers to significant health and safety risks. Automation system offers potential improvement in this area and is especially well suited to the outer-wall painting tasks in concrete structures. This paper introduces the result of gondola-type building management robot(G-BMR) platform and mechanism for moving/tasking on building outer-wall for the outer-wall painting. Its technical and economic feasibility are conducted, and it is concluded that developing G-BMR is physically and economically feasible in this research. And we discuss about the future of G-BMR and automation in construction field.

해양심층수 이용 냉방시스템에 관한 연구 (A Study on the Air Conditioning System by the Low Temperature Energy of the Deep Seawater)

  • 박성제;김효봉;김현주
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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    • pp.253-256
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    • 2006
  • This paper shows the study on application of the law temperature energy in the deep seawater. Deep, cold seawater has long been recognized as a valuable ocean energy resource. Recently, research and experimentation has been conducted on energy systems using deep seawater: deep seawater air conditioning system, ice-making device, salt and fresh-water manufacturing system and the Spray freeze drying system for extracting valuable material of the deep seawater. They are technically and economically feasible today: once installed, the energy is inexhaustible and there are no adverse environmental impacts. Because of the economy of scale in the air conditioning system, the seawater A/C system is most appropriate for supplying multiple buildings or hotels in a coastal area.

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모형토조시험을 통한 준설매립토의 건조특성에 관한 연구 (Desiccation Characteristics of Dredged Soft Clay by Large Model Test)

  • 정하익;오인규;지성현;이승원;이영남
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.591-596
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    • 2001
  • The purpose of this paper Is to present and discuss some of evaporation and desiccation observed in laboratory experiments under controlled conditions, and is to improve PTM(Progressive Trenching Method) operating technique. PTM is the technically feasible and economically justifiable dewatering and desiccation technique for dredged material containment areas. A series of laboratory experiments with large model test were carried out to get evaporation rate and strength increase. Surface desiccation of dredged material is basically changed by evaporation characteristics which is controlled by weather and trench type, etc. This study shows that trench depth and rain fall are important factors in desiccation of dredged soft clay.

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Animal Breeding: What Does the Future Hold?

  • Eisen, E.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권3호
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    • pp.453-460
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    • 2007
  • An overview of developments important in the future of animal breeding is discussed. Examples from the application of quantitative genetic principles to selection in chickens and mice are given. Lessons to be learned from these species are that selection for production traits in livestock must also consider selection for reproduction and other fitness-related traits and inbreeding should be minimized. Short-term selection benefits of best linear unbiased predictor methodology must be weighed against long-term risks of increased rate of inbreeding. Different options have been developed to minimize inbreeding rates while maximizing selection response. Development of molecular genetic methods to search for quantitative trait loci provides the opportunity for incorporating marker-assisted selection and introgression as new tools for increasing efficiency of genetic improvement. Theoretical and computer simulation studies indicate that these methods hold great promise once genotyping costs are reduced to make the technology economically feasible. Cloning and transgenesis are not likely to contribute significantly to genetic improvement of livestock production in the near future.

Feeder Loop Line Control for the Voltage Stabilization of Distribution Network with Distributed Generators

  • Jeong, Bong-Sang;Chun, Yeong-Han
    • Journal of Electrical Engineering and Technology
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    • 제9권1호
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    • pp.1-5
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    • 2014
  • When renewable sources are connected to the distribution network in the form of a distributed generators(DGs), the effect of intermittent output appears as voltage fluctuation. The surplus power at the consumer ends results in the reverse power flow to the distribution network. This reverse power flow causes several problems to the distribution network such as overvoltage. Application of the reactive power control equipment and power flow control by means of BTB inverter have been suggested as the general solutions to overcome the overvoltage, but they are not economically feasible since they require high cost devices. Herein, we suggest the feeder loop line switch control method to solve the problem.

넙치 종묘방류사업의 경제적 효과분석 (Economic Effectiveness of the Olive Flounder (Paralichthys olivaceus) Fry Releasing Program in Korea)

  • 서주남;백진이;김도훈
    • Ocean and Polar Research
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    • 제32권4호
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    • pp.483-488
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    • 2010
  • Since 2000 fry releasing programs in Korea have significantly expanded in order to support the commercial fishing industry through recruitment enhancement of targeted species. Here we investigate the economic effectiveness of the Olive flounder (Paralichthys olivaceus) fry releasing program in Korean waters. The market survey method was used in our analyses. Results show that the B/C ratio, as an indicator of economic evaluation, is 2.56 in the East Sea region, 9.45 in the South Sea region, and 1.34 in the West Sea region, which indicates that the fry releasing program is economically feasible but the economic effectiveness varies from region to region.

Characterization of Functional Groups of Protonated Sargassum polycystum Biomass Capable of Binding Protons and Metal Ions

  • Yun, Yeoung-Sang
    • Journal of Microbiology and Biotechnology
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    • 제14권1호
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    • pp.29-34
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    • 2004
  • Biosorption technology is recognized as an economically feasible alternative for the removal and/or recovery of metal ions from industrial wastewater sources. However, the structure of biosorbents is quite complex when compared with synthetic ion-exchange resins, which makes it difficult to quantify the ion-binding sites. Accordingly, this report describes a well-defined method to characterize the pK values and numbers of biomass functional groups from potentiometric titration data. When the proposed method was applied to Sargassum polycystum biomass as a model biosorbent, it was found that the biomass contained three types of functional groups. In addition, the carboxyl group (pK=$3.7{\pm}0.09$) was found to be the major binding sites ($2.57{\pm}0.06 mmol/g$) for positively-charged heavy-metal ions.