• Title/Summary/Keyword: Economic and non-economic

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Horizontal Wave Pressures on the Crown Wall of Rubble Mound Breakwater under Non-Breaking Condition (경사식방파제의 상치콘크리트에 작용하는 수평파압: 비쇄파조건)

  • Lee, Jong-In;Lee, Geum Yong;Kim, Young-Taek
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.33 no.6
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    • pp.321-332
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    • 2021
  • The crown wall with parapet on top of the rubble mound breakwater represents a relatively economic and efficient solution to reduce the wave overtopping discharge. However, the inclusion of parapet leads to increased wave pressure on the crown wall. The wave pressure on the crown wall is investigated by physical model test. To design the crown wall the wave loads should be available, and the horizontal wave pressure is still unclear. Regarding to the horizontal wave pressure on the crown wall, a series of experiments were conducted by changing the rubble mound type structure and the wave conditions. Based on these results, pressure modification factors of Goda's (1974, 2010) formula have been suggested, which can be applicable for the practical design of the crown wall of the rubble-mound breakwater covered by tetrapods.

Numerical Study on Skin Burn Injury due to Flash Flame Exposure (돌발화염으로 인한 화상예측에 관한 수치해석적 연구)

  • Lee, Jun-Kyoung;Bang, Chang-Hoon
    • Fire Science and Engineering
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    • v.26 no.5
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    • pp.13-20
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    • 2012
  • Many fire-fighters suffer from the burn injuries, and the severe burns are the most catastrophic injury a person can survive, resulting in pain, emotional stress, and tremendous economic costs. It is important to understand the physiology of burns for prevention from skin burns and a successful treatment of a burn patient. But a few researches have been presented because the complex physical phenomena of our inside body like non-linearity characteristics of human skin make them difficult. Thus in this study, thermal analyses of biological tissues exposed to a flash fire causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. The several previous models for skin thermo-physical properties were summarized, and the calculated values with those models of tissue injury were compared with the results obtained by the previous experiment for low heat flux conditions. The skin models with good agreement could be found. Also, the skin burn injury prediction results with the best model for high heat flux conditions by flash flame were suggested.

An Optimal Control Theory on Economic Benefits of Dam Management: A Case of Aswan High Dam in Egypt (최적제어 이론을 이용한 댐 토사관리방안 : 이집트 아스완 댐 사례)

  • Lee, Yoon;Kim, Dong-Yeub
    • Journal of Environmental Policy
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    • v.9 no.2
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    • pp.41-55
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    • 2010
  • This paper analyzes optimal watershed management focusing on reservoir-level sediment removal techniques. Although dams and reservoirs provide several benefits, sedimentation may reduce their storage capacity. As of today, the Aswan High Dam (AHD) in Egypt faces approximately 76% reduced life of the reservoir. Since the AHD is the major fresh water source in Egypt, sustainable use of this resource is extremely important. A model is developed to simultaneously determine optimal sediment removal strategies for upstream soil conservation efforts and reservoir-level sediment control. Two sediment removal techniques are considered: mechanical dredging and hydro-suction sediment removal system (HSRS). Moreover, different levels of upstream soil conservation efforts have introduced to control soil erosion, which is a major contributor of reservoir storage capacity reduction. We compare a baseline case, which implies no management alternative, to non-cooperative and social planners' solution. Our empirical results indicate that the socially optimal sediment removal technique is a mechanical dredging with unconstrained amount with providing a sustainable life of the reservoir. From the empirical results, we find that social welfare can be as high as $151.01 billion, and is sensitive to interest rates and agricultural soil loss.

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A Study on Eco-Efficiency in Public Sector Using Decision Tree and DEA Analysis (의사결정나무와 자료포락 분석을 이용한 공공기관 유형별 환경효율성에 대한 연구)

  • Lim, Mi Sun;Kim, Jinhwa;Choi, Soon Jae
    • Journal of the Korean Operations Research and Management Science Society
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    • v.40 no.1
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    • pp.91-116
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    • 2015
  • This study aims to provide public sectors with eco-efficiency information. To implement the purposes of the study, environmental and economic variables of Eco-Efficiency were identified through decision tree model, then the relative Eco-Efficiencies of 243 public sectors were evaluated through input-oriented DEA (Data Envelopment Analysis) model. Specifically, the amount of public purchasing per a staff and the amount of energy use per a staff were considered as input factors. Sales per a staff was considered as output factor. The result shows that most of the public sectors (94.2%) were evaluated as "inefficient" taking into consideration of average value, 0.501 from market-based public corporations, 0.288 from local public corporations, 0.28 from quasi-market-based public corporations, 0.269 from fund-management-based quasi-governmental institutions, 0.09 from non-classified public institutions, and 0.078 from commissioned-service-based quasi-governmental institutions. Furthermore, it is possible to establish a plan for internal Eco-Efficiency improvement based on information of the reference set. In order to improve the Eco-Efficiency in the public sectors in the long term, environmental impacts of the overall public sectors' operations (e.g., energy saving, water saving, waste reduction, and purchasing of green products) needs to be properly proposed in consideration of BSC (Balanced Scorecard) indicators of public sectors.

Evaluation on Structural Stiffness and Grouting Efficiency of Concrete Track using Elastic Wave Tests (탄성파 기법을 이용한 콘크리트궤도의 구조강성 및 충전상태 평가에 관한 연구)

  • Lee, Il-Wha;Joh, Sung-Ho;Jang, Seung-Yup
    • Journal of the Korean Society for Railway
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    • v.12 no.1
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    • pp.55-64
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    • 2009
  • Recently, concrete track is replacing ballast track for efficient and economic maintenance of track. It considerably offer less maintenance, a longer service life and reduced life-cycle costs. With the aim of achieving high-quality track construction work, of developing tools for quality assurance in new construction and for later technical inspection of material condition, a quality strategy has to be developed. For these purpose, NDT which is using the seismic wave has carried out in situ studies in the test construction section. The used NDT are SASW test, impact echo test and continuous impact echo test. The test is performed 5,353 times on 49 pre-cast concrete track panels to verify the stiffness structure and grouting efficiency of the track structure. To conclude, because of the non-homogeneous characteristic of concrete material. it is restricted to apply the elastic wave test at some aspect. However it is possible to acquisite a sufficient reliability about structural stiffness and grouting efficiency of concrete track.

A Study on the Characteristics of Employed Elderly - Focusing on Employment Status Transition - (취업노인의 특성 연구 - 취업상태변화를 중심으로 -)

  • Son, Ji-A;Park, Soon-Mi
    • Korean Journal of Human Ecology
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    • v.20 no.2
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    • pp.285-298
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    • 2011
  • The purpose of this study was to analyze in detail the employment characteristics of the elderly over 65 years old and to compare those that have experienced no job change in the last 10 years with another group that have experienced job change at least once in the last 10 years. From the 10th wave data(KLIP), participants who were over 65 years old were chosen and their employment status for the last 10 years was reviewed. The results of this study were as follows: first, the analysis of demographic profiles indicated that householders and elderly couples with low education levels and low socioeconomic status were more likely to be employed compared to others. Second, in terms of work-related characteristics, it was revealed that the elderly who were employed tended to be non-paid workers, employers, and self-employed workers, primarily in the farming, fishing, forestry, and the mining industries, these were the elderly workers who had experienced job change three times or more in the last 10 years. Third, the analysis of economic characteristics indicated that elderly who were employed tended to rely more on private income transfers. Last, when the elderly who had experienced no job change in the last 10 years were compared to the elderly who had experienced job change in the last 10 years, the two groups differed significantly in terms of employment status, type of business, and occupation category.

OECD 국가의 이산화탄소 배출량 분해분석

  • Kim, Gwang-Uk;Gang, Sang-Mok
    • Environmental and Resource Economics Review
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    • v.21 no.2
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    • pp.211-235
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    • 2012
  • This paper presents an alternative decomposition technique to identify the relative importance of factors associated with changes in $CO_2$ emissions by using directional distance function to model the joint production of desirable and undesirable outputs. The key feature of the proposed approach is the introduction of fossil and non-fossil fuel energy input efficiencies, productivity change and emission intensity change. For the 27 OECD countries as a whole, the empirical results indicate that economic growth is the most important contributor to $CO_2$ emissions increase, while efficiency change is the most important component to $CO_2$ emissions reduction between 1980 and 2007. For more extensive insights, this paper divided 3 groups according to the emission growth rate and find out that high emission countries show relatively low production efficiencies and technical changes contributing $CO_2$ emissions increase. The results also provide that more strict environmental regulations are needed to improve the pollution intensity in these countries.

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Development of an Online Men's Suits Customizing System using Heuristic Procedure for Wheelchair Users (휴리스틱 기법을 이용한 휠체어 사용자를 위한 온라인 남성정장 맞춤시스템 개발)

  • Jeong, Minseok;Yang, Chuneun;You, Heecheon;Park, Kwangae;Lee, Wonsup
    • Fashion & Textile Research Journal
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    • v.18 no.2
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    • pp.225-234
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    • 2016
  • An online suit-customizing system for the special accessibility needs of wheelchair users should be developed because the demand for business suits by wheelchair users involved in economic activities has increased. This study develops a user interface an online customizing system for men's suits specialized for wheelchair users. This study used a five-step approach: (1) search for online men's suits customizing system in web porter sites, (2) select three sites based on three terms, (3) heuristic testing with five web specialists, (4) development of a system user interface based on suggestions for improvement from the heuristic test, (5) usability testing of the user interface prototype by 10 disabled men in wheelchairs. The interface of Company S had high ratings on interactivity, accessibility, informativeness, and consistency in the heuristic test results; subsequently, a user interface was developed based on suggestions for improvement from the heuristic test. This online user interface for customizing men's suits provides better usability to wheelchair users than existing online interfaces aimed at the non-disabled and disabled; consequently, this study contributes to the commercialization of an online customizing system for men's suits specializing in serving wheelchair users.

Determinants of Shopping Experience for Mall Shoppers: Empirical Investigation in an Emerging City of Raipur (India)

  • Singh, Harvinder;Prashar, Sanjeev;Agarwal, Rashmi;Sharma, Tarun Kumar
    • Asia-Pacific Journal of Business
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    • v.5 no.1
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    • pp.13-21
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    • 2014
  • Shopping malls have become key players in the Indian retail space. Even in upcoming Indian towns, malls have been mushrooming. Raipur, the capital city of the Indian state of Chhattisgarh has witnessed the growth over the last few years. However, this unplanned growth of malls in cities is expected to lead to oversupply of mall space in the near future, making things difficult for mall developers. The study is an attempt to identify appropriate strategies for mall developers to iron out such kinks. This paper presents 'shopping experience' as a tool to compete, succeed and explore its composition in terms of its constituent factors. The paper uses Exploratory Factor Analysis (EFA) on a non-probability sample of 350 respondents. It condenses a set of twenty-two mall variables into five factors that directly influence the shopping experience. These factors included ambience, infrastructure, marketing focus, convenience and safety and security. In terms of significance, shoppers assigned different weightage to each of these factors. The study shed light on interesting insights regarding the expectations of mall shoppers in the city of Raipur. The results though interesting, may be extended to different social, economic and geographic contexts to check the universality. While strategizing, mall developers must assign proportionate effort on the factors based on the respective contribution to shopping experience. In light of intensifying competition in Raipur, the study is significant for future prospects of malls. In the absence of a scientific and objective basis, the developers run risk of making wrong investment and management decisions. This paper is a useful addition to the body of knowledge on management of shopping malls in India and is unique in terms of its focus on mall shoppers in the smaller Indian cities like Raipur.

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Development of Management Performance Index Building BSC System for Hotels (BSC 시스템 구축을 위한 호텔기업의 성과지표 개발)

  • Chung, Tae-Woong
    • The Journal of the Korea Contents Association
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    • v.8 no.9
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    • pp.234-241
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    • 2008
  • The feature of the hotel business as a labor intensive industry and its heavy dependence on man power is relatively bigger than other industries. the important factors influencing the customer`s decision making are tangible facilities and intangible service qualities. however, the changes in economic situation are also seriously influencing them. So hotels are started to find other IT(information technology) systems. BSC which has been recognized as one of barometers to establish management performance is one of them. The purpose of this study was to develop KPI(key performance indicator) by using the BSC(Balanced Scorecard) for evaluating hotel management performance. This thesis presents customer performance, inner process performance, learning and growing performance as non-financial factors and tries to examine the cause and effect in the hotel industry. Hotels have to know nonfinancial performance which has positively relate to financial performance. To introduce BSC system is not to lead increasing income and bettermenting service quality, satisfacting customer needa for hotels, But to lead developing value enhancement to hotel enterprises and present process.