• Title/Summary/Keyword: improving efficiency

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The Evaluation Research of Weihai Fishery Production Efficiency Based on DEA Model (基于DEA模型的威海渔业生产效率评价研究)

  • Wu, Yinuo
    • Journal of East Asia Management
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    • v.3 no.1
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    • pp.11-23
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    • 2022
  • Under the circumstances of China's slower economic growth, the first document ofthe central committee of the CPC continue to focus on "three agricultures" problems, agriculture play a basic role on China's economic. Since 2007, the first document directly stresses the important role of agricultural and fisheries every year. Central Government Working Report of 2015 also stresses that under the new normal of economy, it is important to improve quality and efficiency of agriculture. Agricultural focus going forward will be on improving capacity of competitiveness, innovation and sustainable development.The fishery as an important part of agriculture plays a vital role in the protection of national food security, the prosperity of the rural economy and the optimization of national food structure. However, the situation faced on accelerating the speed of Chinese fisheries is still grim. As an important fishery breeding city in my country, Weihai has achieved remarkable results in the development of fisheries. Based on the input-output indicators of Weihai City from 2010 to 2020, this article uses the DEA model method to conduct a comprehensive analysis of the factors affecting the fishery production efficiency in Weihai City. This paper calculates the two stages of comprehensive efficiency, pure technical efficiency and scale efficiency, and comprehensive compares the two stages. The research results show that: From 2010 to 2020, the average comprehensive technical efficiency of Weihai fishery was 0.928, the average scale efficiency was 0.963, and the average pure technical efficiency was 0.963. The comprehensive technical efficiency of Weihai fishery production showed an upward and downward trend, the pure technical efficiency showed a downward and then upward trend, and the pure technical efficiency showed a fluctuating trend.

An Estimation of Domestic Regional Energy Efficiency Using Stochastic Distance Function (확률적 거리함수를 활용한 지역별 에너지효율성 추정)

  • Jeong, Dasom;Kang, Sangmok
    • Environmental and Resource Economics Review
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    • v.30 no.4
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    • pp.581-605
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    • 2021
  • The purpose of this study is to provide basic data for improving energy efficiency by estimating the regional energy efficiency in Korea using the stochastic frontier approach beyond the energy intensity that has been traditionally used as an indicator of energy efficiency. In this paper, energy efficiency and energy intensity efficiency were estimated as a stochastic distance function from 1998 to 2018 for 16 cities and provinces in Korea. In addition, the robustness of energy efficiency according to the capital stock estimation methods which had been mixed in previous studies was reviewed. As a result of the analysis, there is a significant change in regional rankings according to the three energy efficiency indicators, so they should be used complementary to each other. Second, while the energy efficiency improved little by little over time, the energy intensity efficiency decreased slightly though. Lastly, energy efficiency by region according to the capital stock estimation method was not robust. Care must be taken in estimating capital stock, which is important in economic analysis.

A PDPWM Based DC Capacitor Voltage Control Method for Modular Multilevel Converters

  • Du, Sixing;Liu, Jinjun;Liu, Teng
    • Journal of Power Electronics
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    • v.15 no.3
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    • pp.660-669
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    • 2015
  • This paper presents a control scheme with a focus on the combination of phase disposition pulse width modulation (PDPWM) and DC capacitor voltage control for a chopper-cell based modular multilevel converter (MMC) for the purpose of eliminating the time-consuming voltage sorting algorithm and complex voltage balancing regulators. In this paper, the convergence of the DC capacitor voltages within one arm is realized by charging the minimum voltage module and discharging the maximum voltage module during each switching cycle with the assistances of MAX/MIN capacitor voltage detection and PDPWM signals exchanging. The process of voltage balancing control introduces no extra switching commutation, which is helpful in reducing power loss and improving system efficiency. Additionally, the proposed control scheme also possess the merit of a simple executing procedure in application. Simulation and experimental results indicates that the MMC circuit together with the proposed method functions very well in balancing the DC capacitor voltage and improving system efficiency even under transient states.

Development of R&D Knowledge Management System (KMS) for Science & Technology Research Institutes (과학기술 종합지식 경영시스템 (R&D-KMS) 구축)

  • Shim, Kyung
    • Journal of Korean Society of Archives and Records Management
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    • v.1 no.2
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    • pp.121-158
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    • 2001
  • Development of R&D Knowledge Management System for Science & Technology Research Institutes, which was initiated early 2001, was introduced. The project, funded by the Ministry of Science and Technology, is being carried out by several R&D institutes in cooperation With implementers. The purposes of the project are: sharing knowledge about on-going research progresses and existing research results, facilitating cooperative efforts among research staff, teams, and institutes, and improving the efficiency of research project administration. The system consists of 4 components that are highly intertwined: Knowledge Portal, Knowledge Repository, Project Administration System and Groupware. This 3-year project will benefit R&D researchers, and R&D project carrying-out institutes and government project administration organization by facilitating research and development activities, and improving management efficiency, respectively.

The Effect of Computerized Tax Services in Improving Tax Performance Moderated by Governance

  • MASWADEH, Sanaa Nazami;HANANDEH, Tariq Samih
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.12
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    • pp.1167-1174
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    • 2020
  • This study aims to evaluate the effect of computerized tax services in improving tax performance by moderating governance principles in Jordanian tax income departments. The study is based on a questionnaire distributed to income tax auditors, who were chosen by the simple random sampling method, so that 170 questionnaires were subjected to statistical analysis. The study models were formulated in the form of simple and multiple regression equations to test the hypotheses of the study, in addition to relying on One Sample T-test to calculate the mean of questionnaire answers. The most prominent research results is that the application of tax governance principles through the provision of computerized tax services is reflected in the increase in confidence between taxpayers and income tax departments, the efficiency of tax performance, and tax proceeds. Also, the study pointed out the importance of the income tax departments to prepare strategic plans regarding the development and the follow-up of modern technologies related to computerized tax services. It especially regards linking and collecting tax from taxpayers such as via electronic tax payment and collection system, in order to ensure the speed of completion, accuracy of calculation, and raising the efficiency of tax performance.

Temperature Control of BIPV system considering out air temperature (외기온도를 고려한 BIPV 시스템의 온도제어)

  • Baek, Jeong-Woo;Ko, Jae-Sun;Choi, Jung-Sik;Kang, Sung-Jun;Jang, Mi-Geum;Kim, Soon-Young;Chung, Dong-Hwa
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.10a
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    • pp.371-374
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    • 2009
  • This paper presents a cooling system using thermoelectron for improving the output of BIPV module. The temperature characteristic in regard to improving the output of BIPV system has rarely been studied up to now but some researchers only presented the method using a ventilator. The cooling system efficiency of BIPV module applied to a ventilator mainly depends on the weather such as wind, insolation etc. Because the cooling system of BIPV module using a ventilator is so sensitive, that is being set off by wind speed at all time but is unable to operate in the NOCT(Nominal Operating Cell Temperature) which is able to make the maximum output The paper presents the cooling system using thermoelectron so as to solve such problems. The temperature control of thermoelectron can be controlled independently in the outside environment because that is performed by micro-controller. The temperature control of thermoelectron, also, can be operated around NOCT through algorism of the temperature control. Therefore, outputs of the whole system increase and the efficiency rises. The paper demonstrates the validity of proposed method by comparing the data obtained through a experiment of the cooling method of BIPV using a ventilator and proposed thermoelectron.

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Pigment Reduction to Improve Photosynthetic Productivity of Rhodobacter sphaeroides

  • Kim, Nag-Jong;Lee, Jeong-Kug;Lee, Choul-Gyun
    • Journal of Microbiology and Biotechnology
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    • v.14 no.3
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    • pp.442-449
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    • 2004
  • Improving the light utilization efficiency of photosynthetic cells in photobioreactors (PBRs) is a major topic in algal biotechnology. Accordingly, in the current study we investigated the effect and suitability of photosynthetic pigment reduction for improving light utilization efficiency. The light-harvesting complex II (LH-II) genes of Rhodobacter sphaeroides were removed to construct a mutant strain with less pigment content. The mutant strain exhibited a slower growth rate than the wild-type under a low light intensity, while the mutant grew faster under a high light intensity. In addition, the specific absorption coefficient was lower in the mutant due to its reduced pigment content, thus it seemed that light penetrated deeper into its culture broth. However, the distance (light penetration depth) from the surface of the PBR to the compensation point did not increase, due to an increase in the compensation irradiance of the mutant strain. Experimental data showed that a reduced photosynthetic pigment content, which lessened the photoinhibition under high-intensity light, helped the volumetric productivity of photosynthetic microorganisms.

A Study on the Spray Characteristics of the Cold-Fog Spray with Ultrasonic Forcing (초음파적용 상온연무기의 분무특성에 관한 연구)

  • Song Min-Geun;Lee Kyung-Youl;Son Sung-Woo;La Woo-Jung;Ju Eun-Sun
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.299-302
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    • 2002
  • Characteristics of the twin fluid spray with ultrasonic forcing are examined in order to obtain the high efficiency of cold fog spray of the automatic pest control machine which has been widely used for the equipment cultivation recently. An electrostrictive vibrator of PZT BLT and a magnetostrictive vibrator of ${\pi}type$ with 28 kHz are applied as the ultrasonic transducer. All experiments are made and observed in 4 methods of spray ; a conventional spray method without ultrasonic forcing, an indirect vibration method with ultrasonic forcing, an improving duality method by ultrasonic forced within liquid, and a combined use method with both of the indirect vibration method and the improving quality method. In results, It was clarified that the ultrasonic effects the atomization of spray droplets and its efficiency is about $10{\%}$ and especially much more in the case of the combined use method.

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Cooling System Development of BIPV Module Using Thermoelectron (열전소자를 이용한 BIPV 모듈의 냉각시스템 개발)

  • Choi, Jung-Sik;Ko, Jae-Sub;Chung, Dong-Hwa
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.9
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    • pp.1555-1562
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    • 2008
  • This paper presents a cooling system using thermoelectron for improving the output of BIPV module. The temperature characteristic in regard to improving the output of BIPV system has rarely been studied up to now but some researchers only presented the method using a ventilator. The cooling system efficiency of BIPV module applied to a ventilator mainly depends on the weather such as wind, insolation etc. Because the cooling system of BIPV module using a ventilator is so sensitive, that is being set off by wind speed at all time but is unable to operate in the NOCT(Nominal Operating Cell Temperature) which is able to make the maximum output. The paper presents the cooling system using thermoelectron so as to solve such problems. The temperature control of thermoelectron can be controlled independently in the outside environment because that is performed by micro-controller. The temperature control of thermoelectron, also, can be operated around NOCT through algorism of the temperature control. Therefore, outputs of the whole system increase and the efficiency rises. The paper demonstrates the validity of proposed method by comparing the data obtained through a experiment of the cooling method of BIPV using a ventilator and proposed thermoelectron.

On Improving Efficiency of Environmental R&D Management System : A Survey Study (환경관련 R&D사업 운영체계의 문제점과 개선방안 -설문조사를 중심으로-)

  • Kim, Hong-Kyun;Lim, Jong-Soo
    • Environmental and Resource Economics Review
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    • v.13 no.3
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    • pp.469-497
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    • 2004
  • Environmental R&D management system has been analyzed with LCA method. Based on the analysis, we found the following four elements were essential for improving effciency of environmental R&D management system: establishment of an information clearinghouse that collects and distributes information on the status of the domestically owned environmental technology, Periodic survey of the environmental technology demand to give guidance in selecting the environmental R&D project that are to be subsidized, dissemination of information on the technology transfer and commercialization assistance program, and increased funding as well as the expansion of project categories eligible for R&D subsidy.

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