• 제목/요약/키워드: Reduction strategies

검색결과 683건 처리시간 0.028초

외식산업분야 발전을 위한 아웃소싱의 국제비교연구 -한.영 트랜드를 중심으로- (A Study on international comparison of outsourcing trends in thefoodservice Industry)

  • 김기영
    • 한국조리학회지
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    • 제10권1호
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    • pp.1-13
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    • 2004
  • The problems and the limits of outsourcing strategies are disclosure of the knowhow to someone and rapid confrontation of difficulties by a outsourcing-supply company, limitations of quality control and hold-up of quality. From the result of this study, we found that development of outsourcing strategies will be not vertical relationship between a outsourcing-supply company and a outsourcing-demand company but horizontal relationship (co-sourcing) between those supply and demand company. Especially, core-affairs, control of operating costs and costs reduction must have the precise purpose and carry out capacity and affairs of organization.

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SRM의 저소음 구동을 위한 여자방식에 따른 특성해석 (Characteristic Analysis of Excitation Method for Reduction of Acoustic Noise of SRM)

  • 김태형;안진우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.15-18
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    • 2005
  • Switched reluctance drive does exhibit higher levels of vibration and acoustic noise than that of most competing drives. The main source of vibration in the switched reluctance drive is generated by rapid change of radial magnetic force when phase current is extinguished during commutation action. In this paper, some excitation method is proposed to reduce vibration and acoustic noise of the switched reluctance drive. The excitation strategies considered in this research are 1-phase, 2-phase and hybrid excitation method. 1-phase method is a conventional and 2-phase method is excited 2 phases simultaneously. The hybrid excitation has 2-phase excitation by long dwell angle as well as conventional 1-phase excitation. The vibration and acoustic noise are compared and tested. Suggested 2-phase and hybrid strategies reduce acoustic noise because the scheme reduces abrupt change of excitation level by distributed and balanced excitation.

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Effects of multiple MR dampers controlled by fuzzy-based strategies on structural vibration reduction

  • Wilson, Claudia Mara Dias
    • Structural Engineering and Mechanics
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    • 제41권3호
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    • pp.349-363
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    • 2012
  • Fuzzy logic based control has recently been proposed for regulating the properties of magnetorheological (MR) dampers in an effort to reduce vibrations of structures subjected to seismic excitations. So far, most studies showing the effectiveness of these algorithms have focused on the use of a single MR damper. Because multiple dampers would be needed in practical applications, this study aims to evaluate the effects of multiple individually tuned fuzzy-controlled MR dampers in reducing responses of a multi-degree-of-freedom structure subjected to seismic motions. Two different fuzzy-control algorithms are considered, a traditional controller where all parameters are kept constant, and a gain-scheduling control strategy. Different damper placement configurations are also considered, as are different numbers of MR dampers. To determine the robustness of the fuzzy controllers developed to changes in ground excitation, the structure selected is subjected to different earthquake records. Responses analyzed include peak and root mean square displacements, accelerations, and interstory drifts. Results obtained with the fuzzy-based control schemes are compared to passive control strategies.

수요요인을 반영한 개인용 항공기 개발전략 연구 (A Study on R&D Strategies of Personal Air Vehicle based on Demand Factors)

  • 변상규;강범수
    • 한국항공운항학회지
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    • 제29권3호
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    • pp.15-23
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    • 2021
  • Personal Air Vehicle is expected to be a promising solution to relieve traffic congestion using urban airspace. The development of related technologies such as materials or batteries has been accelerated. In addition, commercial transportation services are being prepared. When fierce competition begins in the PAV market, even technologically superior products will disappear without choices by consumers. Therefore, demand factors should be reflected in PAV development to enhance competitiveness. In the paper, values were estimated for the major technological attributes of PAV. Stated preference data were collected through a survey, and the conjoint method and ordered probit model were adopted. Thereafter, it was confirmed that the value would be high in the order of dual mode, drone-type appearance, and noise reduction. Some R&D strategies were proposed based on this.

전기경련치료에 대한 사회적 낙인과 해소 방안 (Social Stigmata of Electroconvulsive Therapy and Their Reduction Strategies)

  • 이준희;김민아;김세현;이유상;권준수
    • 생물정신의학
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    • 제27권2호
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    • pp.37-41
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    • 2020
  • Modified electroconvulsive therapy (ECT) which started in 1950s is a safe and efficacious treatment for several mental disorders including mood disorders and psychotic disorders. However, its usage in present days is still limited by misconceptions and stigmata of ECT. This paper overviews the background from which the stigmata of ECT stemmed and the current status of stigmata surrounding ECT among the public and medical professionals. In addition, a few potential strategies for reducing stigmata of ECT are provided in this review.

Clinical efficacy of activated irrigation in endodontics: a focused review

  • Amelia Wan Tin Cheung;Angeline Hui Cheng Lee;Gary Shun Pan Cheung
    • Restorative Dentistry and Endodontics
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    • 제46권1호
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    • pp.10.1-10.16
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    • 2021
  • Root canal debridement, which includes the removal of infected tissues and microbial biofilms, is considered the corner stone of root canal treatment. Chemical adjuncts play a multitude of functions in this regard, as tissue solvents, antimicrobial agents and for removing the smear layer. These adjuncts (irrigants) are usually delivered using a syringe and needle. With increasing knowledge of the complexity of root canal anatomy and tenacity of microbial biofilms, the need for strategies that potentiate the action of these irrigants within the root canal system cannot be overemphasized. Several such activated irrigation strategies exist. The aim of this review is to comprehensively discuss the different irrigant activation methods from the context of clinical studies.

SCR 촉매와 AOC 촉매에서 환원제 분사에 따른 $NO_x$ 저감효율과 $NH_3$ 변환효율에 관한 실험적 연구 (An Experimental Study on $NO_x$ Reduction Efficiency and $NH_3$ Conversion Efficiency under Various Conditions of Reductant Injection on SCR and AOC)

  • 동윤희;최정황;조용석;이성욱;이승호;오상기;박현대
    • 한국자동차공학회논문집
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    • 제18권5호
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    • pp.85-90
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    • 2010
  • As the environmental regulation of vehicle emission is strengthened, investigations for $NO_x$ and PM reduction strategies are popularly conducted. Two current available technologies for continuous $NO_x$ reduction onboard diesel vehicles are Selective Catalytic Reduction (SCR) using aqueous urea and lean $NO_x$ trap (LNT) catalysts. The experiments were conducted to investigate the $NO_x$ reduction performance of SCR system which can control the ratio of $NO/NO_2$, temperature and SV(space velocity), and the model gas was used which is similar to a diesel exhaust gas. The maximum reduction efficiency is indicated when the $NO:NO_2$ ratio is 1:1 and the SV is 30,000 $h^{-1}$ in $300^{\circ}C$. Generally, ammonia slip from SCR reactors are rooted to incomplete conversion of $NH_3$ over the SCR. In this research, slip was occurred in 6cases (except low SV and $NO:NO_2$ ratio is 1:1) after SCR. Among 6 case of slip occurrence, the maximum conversion efficiency is observed when SV is 60,000 $h^{-1}$ in $400^{\circ}C$.

외식기업의 기능적 일치성이 정보탐색비용의 절감과 긍정적 감정, 부정적 감정 그리고 충성도에 미치는 영향 (The Effect of Functional Congruence on the Information Search Cost Reduction, Positive Emotions, Negative Emotions, and Loyalty in Restaurant)

  • 한영위;최상혁;손정영
    • 한국프랜차이즈경영연구
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    • 제13권3호
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    • pp.45-55
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    • 2022
  • Purpose: Consumers' experience of functional attributes is remembered, and the experience lowers the cost of consumers' input from their point of view and reduces uncertainty. It also plays an important role in consumers' positive emotions and responses. Accordingly, if information search costs are reduced in terms of the costs perceived by consumers about restaurants, a strategy differentiated from other companies can be established. Therefore, this study investigated the effect of functional congruence of restaurant stores on information search cost reduction, positive/negative emotions, and loyalty. Research Design, Data, and Methodology: This study investigated functional congruence, information search cost reduction, and positive/negative emotions. The structural relationship between loyalty was analyzed. To verify this, a research hypothesis was established based on previous studies and a research model was constructed. The questionnaire items were modified and used according to the current study, based on previous studies. The data were collected using the questionnaire method from 187 people who had dining out experience. Frequency analysis was performed to confirm demographic characteristics. Reliability, convergent validity, and discriminant validity of the collected data were verified. The research model was analyzed with a structural equation modeling (SmartPLS 4). Results: The findings show that functional congruence had significant positive effects on information search cost reduction and positive emotion, but no significant effect on negative emotion. Information search cost reduction had significant positive effects on positive emotion/negative emotion but did not significantly affect loyalty. Lastly, both positive and negative emotions had significant positive effects on loyalty. Conclusion: Based on transaction cost theory, this study found how functional congruence and information search cost reduction influence consumers' emotions. The functional attributes of restaurants were perceived by customers as information, thus uncertainty was decreased. Finally, appropriate management strategies and implications of functional congruence and information search cost in the restaurant were suggested.

Improvement of the Planting Method to Increase the Carbon Reduction Capacity of Urban Street Trees

  • Kim, Jin-Young;Jo, Hyun-Kil;Park, Hye-Mi
    • 인간식물환경학회지
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    • 제24권2호
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    • pp.219-227
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    • 2021
  • Background and objective: Urban street trees play an important role in carbon reduction in cities where greenspace is scarce. There are ongoing studies on carbon reduction by street trees. However, information on the carbon reduction capacity of street trees based on field surveys is still limited. This study aimed to quantify carbon uptake and storage by urban street trees and suggest a method to improve planting of trees in order to increase their carbon reduction capacity. Methods: The cities selected were Sejong, Chungju, and Jeonju among cities without research on carbon reduction, considering the regional distribution in Korea. In the cities, 155 sample sites were selected using systematic sampling to conduct a field survey on street environments and planting structures. The surveyed data included tree species, diameter at breast height (DBH), diameter at root collar (DRC), height, crown width, and vertical structures. The carbon uptake and storage per tree were calculated using the quantification models developed for the urban trees of each species. Results: The average carbon uptake and storage of street trees were approximately 7.2 ± 0.6 kg/tree/yr and 87.1 ± 10.2 kg/tree, respectively. The key factors determining carbon uptake and storage were tree size, vertical structure, the composition of tree species, and growth conditions. The annual total carbon uptake and storage were approximately 1,135.8 tons and 22,737.8 tons, respectively. The total carbon uptake was about the same amount as carbon emitted by 2,272 vehicles a year. Conclusion: This study has significance in providing the basic unit to quantify carbon uptake and storage of street trees based on field surveys. To improve the carbon reduction capacity of street trees, it is necessary to consider planning strategies such as securing and extending available grounds and spaces for high-density street trees with a multi-layered structure.

서낙동강 유역 해반천의 수질 개선을 위한 비점오염관리대책 효과 분석 (Assessment of the Non-point Source Pollution Control Strategies for Water Quality Improvement in the Haeban Stream of West Nakdong River Watershed)

  • 김예진
    • 한국습지학회지
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    • 제26권1호
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    • pp.1-9
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    • 2024
  • 이 연구에서는 서낙동강을 구성하는 소유역 중 대지면적 비율이 크고 인구밀도가 높은 해반천 유역의 유출 및 수질을 모의하기 위한 HSPF(Hydrological Simulation Program-FORTRAN)모형을 개발하였다. 유역에서 발생하는 비점오염 부하량을 관리하기 위한 세 가지 시나리오가 개발되어 모형에 적용되었고, 오염부하량의 감소와 부하지속곡선에 대비한 수질 기준 초과율이 분석되었다. 시나리오는 비점오염의 발생을 줄이기 위한 도로 청소, 다양한 저영향 개발 기법을 고려한 유출 저감 조치, 그리고 강으로 들어가는 비점오염원을 완화하기 위한 유입 저감 조치로 구성되었다. 첫 번째 시나리오에서는 김해시의 도로 청소 차량 수와 같은 실제 조건이 고려되었으며, 두 번째와 세 번째 시나리오에서는 적용 가능한 토지 이용별 면적의 50%에 저영향 개발 기법을 적용하는 것으로 적용되었다. 모든 세 가지 조치를 적용한 결과, BOD 오염 물질 부하가 58.28%, T-N은 58.49%, T-P는 51.56% 감소할 수 있는 것으로 도출되었다. 또한, 5년간 누적된 수질 측정의 60번째 백분위수를 목표 수질로 설정하고 구축된 유량지속곡선에 의한 초과율분석 결과, 결과적으로, BOD의 경우 조치 적용 전 41.57%의 초과율이 조치 후 16.32%로 감소하여, 초과율이 25.25% 감소하였다. T-N의 경우 조치 전 40.31%에서 조치 후 22.84%로, T-P의 경우 62.43%에서 27.22%로 감소하였다.