• 제목/요약/키워드: utility estimation

검색결과 171건 처리시간 0.028초

GIS를 이용한 로스엔젤레스에 매설된 강관 손상 평가 (Loss Estimation of Steel Pipeline Damage in Los Angeles Using GIS)

  • Jeon, Sang-Soo
    • 한국지반공학회논문집
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    • 제20권2호
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    • pp.47-58
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    • 2004
  • 강관은 Northridge 지진이 발생했을 당시 산사태가 일어나는 언덕이나 산악지역에 매설되어 있었다. 본 논문은 지리정보체계(GIS) 시스템에서 위치에 따라 강관을 서로 다른 유형별로 분류하고 정의하였다. 이 논문은 지반속도와 강관의 손상관계를 분석하고 Northridge 지진 시 발생한 산사태의 영향을 받았던 지역을 조사하였다. 하나의 주목할 만한 사실은 Northridge 지진 후 강관의 손상률이 다른 종류의 매설관, 특히 캐스트아이런(CI)보다 더 높았다는 것이다. Northridge 지진으로 인한 상대적으로 높은 강관의 손상률은 가장 큰 내부압력을 요하는 곳에서의 설치관례와 부식으로 인한 영향으로 해석될 수 있다.

A Study on Commercial Power of Traditional Market

  • Baik, Key-Young;Youn, Myoung-Kil
    • 동아시아경상학회지
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    • 제4권2호
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    • pp.1-11
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    • 2016
  • This study investigated commercial power theory of traditional market through the analysis of literature review. Consumers' store selection models are made up a theory based on normative hypothesis, theory of mutual reaction, utility function estimation model, and cognitive-behavioral model. Detailed models are as follows. Normative hypothesis based theory is divided into Reilly's retail gratification theory and Converse's revised retail g ratification theory. Interaction theory is composed of Huff's probability gratification theory, MCI model and Multi-nominal Logit Model (MNL model). There are four models in retail organization position theory such as central place theories, single store position theory, multi store position - assign model, and retail growth potential model. In case of single store position theory, theoretical and empirical techniques have developed for a decision to optimum single store position. Those are like these, a check list, the most simple and systematic method, analogy, and microanalysis technique. Aforementioned models are theoretical and mathematical commercial power measurement and/or model. The study has rather limitations because the variation factors included in formula are only a part of actual commercial power. Therefore, further study shall be made continuously to commercial power areas and variables.

교량구조물의 진동영향평가를 위한 동하중 이상화모델링 기법 연구 (A Study of Load Modeling Method for Vibration Estimation of Bridge Structures)

  • 박연수;홍혜진;공강주;김정주
    • 한국방재학회 논문집
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    • 제6권2호
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    • pp.9-15
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    • 2006
  • 토목구조물은 주로 안전성을 위주로 설계되어 왔으나 최근 들어 토목기술에 대한 환경친화적 측면이 중시되어지는 가운데 구조물의 사용성과 안정성의 비중이 커져가고 있다. 또한 기술의 발달로 재료의 고강도화가 이루어져 구조부재 자체의 크기나 단면적이 줄어들었는데 이는 교량구조물의 과도한 처짐과 진동을 동시에 야기했다. 따라서 본 연구에서는 교량 구조물의 통과주체가 되는 차량동하중과 인체보행하중이 교량에 미치는 처짐과 진동에 대한 영향을 적용 가능한 가장 이상화 된 모델링을 찾아내어 진동영향평가 할 수 있도록 하기 위한 연구를 수행하였다.

Appliance Load Profile Assessment for Automated DR Program in Residential Buildings

  • Abdurazakov, Nosirbek;Ardiansyah, Ardiansyah;Choi, Deokjai
    • 스마트미디어저널
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    • 제8권4호
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    • pp.72-79
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    • 2019
  • The automated demand response (DR) program encourages consumers to participate in grid operation by reducing power consumption or deferring electricity usage at peak time automatically. However, successful deployment of the automated DR program sphere needs careful assessment of appliances load profile (ALP). To this end, the recent method estimates frequency, consistency, and peak time consumption parameters of the daily ALP to compute their potential score to be involved in the DR event. Nonetheless, as the daily ALP is subject to varying with respect to the DR time ALP, the existing method could lead to an inappropriate estimation; in such a case, inappropriate appliances would be selected at the automated DR operation that effected a consumer comfort level. To address this challenge, we propose a more proper method, in which all the three parameters are calculated using ALP that overlaps with DR time, not the total daily profile. Furthermore, evaluation of our method using two public residential electricity consumption data sets, i.e., REDD and REFIT, shows that our energy management systems (EMS) could properly match a DR target. A more optimal selection of appliances for the DR event achieves a power consumption decreasing target with minimum comfort level reduction. We believe that our approach could prevent the loss of both utility and consumers. It helps the successful automated DR deployment by maintaining the consumers' willingness to participate in the program.

주제공원의 경쟁력 제고 방안에 관한 연구: Hybrid Conjoint Analysis의 적용 (Application of Hybrid Conjoint Analysis to Improve Competitive Power of Theme Parks in Seoul and Its Suburbs)

  • 홍성권
    • 한국조경학회지
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    • 제23권2호
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    • pp.1-16
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    • 1995
  • This study was carried out to suggest method which can be used to improve competitive power of theme parks. The characteristics of Hybrid Conjoint Analysis were described and its usefulness for identification of specific types of service theme parks have to provide was tested "Lotte World, " "Seoul land," and "farmland" were selected as study areas, and .7 attributes with 3 levels were utilized for analyses. Master design with 81 profiles was constructed to meet the requirement of ′Compromise Plan 1,′and data was collected by in-personal interviews on the study areas. Respondents were grouped by cluster analysis, and their characteristics were analyzed by discriminant analysis. Then, part-worth of each attribute . was estimated by stagewise estimation model Calibrated model of each group did not show part-worths of attributes clearly because both main effects and 2-way interaction effects were included in the models. Therefore, calibrated models′ coefficients were used to calculate utilities of all possible combinations of attributes levels. The results showed that managers of theme parks have several options for providing a new service: the combination of attribute levels with the highest utility is they however, they can choose the other combinations with next highest utlities is they can not afford it. Several suggestions were described to cope with the problems when Hybrid Conjoint Analysis is applied to landscape architectural study.

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ARIMA Based Wind Speed Modeling for Wind Farm Reliability Analysis and Cost Estimation

  • Rajeevan, A.K.;Shouri, P.V;Nair, Usha
    • Journal of Electrical Engineering and Technology
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    • 제11권4호
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    • pp.869-877
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    • 2016
  • Necessity has compelled man to improve upon the art of tapping wind energy for power generation; an apt reliever of strain exerted on the non-renewable fossil fuel. The power generation in a Wind Farm (WF) depends on site and wind velocity which varies with time and season which in turn determine wind power modeling. It implies, the development of an accurate wind speed model to predict wind power fluctuations at a particular site is significant. In this paper, Box-Jenkins ARIMA (Auto Regressive Integrated Moving Average) time series model for wind speed is developed for a 99MW wind farm in the southern region of India. Because of the uncertainty in wind power developed, the economic viability and reliability of power generation is significant. Life Cycle Costing (LCC) method is used to determine the economic viability of WF generated power. Reliability models of WF are developed with the help of load curve of the utility grid and Capacity Outage Probability Table (COPT). ARIMA wind speed model is used for developing COPT. The values of annual reliability indices and variations of risk index of the WF with system peak load are calculated. Such reliability models of large WF can be used in generation system planning.

Automatic Extraction of Road Network using GDPA (Gradient Direction Profile Algorithm) for Transportation Geographic Analysis

  • Lee, Ki-won;Yu, Young-Chul
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.775-779
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    • 2002
  • Currently, high-resolution satellite imagery such as KOMPSAT and IKONOS has been tentatively utilized to various types of urban engineering problems such as transportation planning, site planning, and utility management. This approach aims at software development and followed applications of remotely sensed imagery to transportation geographic analysis. At first, GDPA (Gradient Direction Profile Algorithm) and main modules in it are overviewed, and newly implemented results under MS visual programming environment are presented with main user interface, input imagery processing, and internal processing steps. Using this software, road network are automatically generated. Furthermore, this road network is used to transportation geographic analysis such as gamma index and road pattern estimation. While, this result, being produced to do-facto format of ESRI-shapefile, is used to several types of road layers to urban/transportation planning problems. In this study, road network using KOMPSAT EOC imagery and IKONOS imagery are directly compared to multiple road layers with NGI digital map with geo-coordinates, as ground truth; furthermore, accuracy evaluation is also carried out through method of computation of commission and omission error at some target area. Conclusively, the results processed in this study is thought to be one of useful cases for further researches and local government application regarding transportation geographic analysis using remotely sensed data sets.

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한전계통의 송전망 고장확률 산정을 위한 상정고장 DB 관리시스텀(ezCas) 개발 (Development of Outage Data Management System to Calculate the Probability for KEPCO Transmission Systems)

  • 차승태;전동훈;김태균;전명렬;추진부;김진오;이승혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.88-90
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    • 2004
  • Data are a critical utility asset. Collecting correct data on site leads to accurate information. Data, when gathered with foresight & properly formatted, are useful to both existing database and easily transferable to newer, more comprehensive historical outage data. However, when investigating data items options, the task, can be an arduous one, often requiring the efforts of entire committees. This paper firstly discusses the KEPCO's past 10 years of historical outage data which include meterological data, and also by several elements of the National Weather Service, failure rate, outage duration, and probability classification, etc. Then, these collected data are automatically stored in an Outage Data Management System (ODMS), which allows for easy access and display. ODMS has a straight-forward and easy-to-use interface. It lets you to navigate through modules very easily and allows insertion, deletion or editing of data. In particular, this will further provide the KEPCO that not only helps with probabilistic security assessment but also provides a platform for future development of Probability Estimation Program (PEP).

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T-method를 이용한 고층 아파트 욕실 배기 시스템의 층별 유량분배 해석 (Analysis of Air Flow Rate Distribution for the Bathroom Exhaust System in High-rise Buildings Using T-method)

  • 문종선;강석윤;이승철;유호선;이재헌
    • 설비공학논문집
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    • 제16권3호
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    • pp.265-272
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    • 2004
  • Based on the T-method, a new scheme for predicting air flow rate distribution in a bathroom exhaust system is developed. Introduction of individual duct route enables us to disintegrate a complicated multi-fan ductwork into a set of simultaneous single-fan subsystems. The scheme is validated via the analysis of a well-posed test problem, showing physical consistency. In order to demonstrate the utility and capability of our method, the bathroom ventilation system in a 20-story residential building is selected as an example. Under the typical design condition, the air flow rate of each exhaust fan at the balancing point is successfully predicted, and such information can lead to an engineering estimation for the overall system performance. While some deficiencies in ventilation are found at bathrooms at lower floors with 6mmAq-rated exhaust fans, they disappear over the whole building by using fans of enhanced static pressures, 7 and 8mmAq. Finally the present scheme seems to be useful for practical design of multi-branched, multi-fan ventilation systems.

Estimation and Prediction of Financial Distress: Non-Financial Firms in Bursa Malaysia

  • HIONG, Hii King;JALIL, Muhammad Farhan;SENG, Andrew Tiong Hock
    • The Journal of Asian Finance, Economics and Business
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    • 제8권8호
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    • pp.1-12
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    • 2021
  • Altman's Z-score is used to measure a company's financial health and to predict the probability that a company will collapse within 2 years. It is proven to be very accurate to forecast bankruptcy in a wide variety of contexts and markets. The goal of this study is to use Altman's Z-score model to forecast insolvency in non-financial publicly traded enterprises. Non-financial firms are a significant industry in Malaysia, and current trends of consolidation and long-term government subsidies make assessing the financial health of such businesses critical not just for the owners, but also for other stakeholders. The sample of this study includes 84 listed companies in the Kuala Lumpur Stock Exchange. Of the 84 companies, 52 are considered high risk, and 32 are considered low-risk companies. Secondary data for the analysis was gathered from chosen companies' financial reports. The findings of this study show that the Altman model may be used to forecast a company's financial collapse. It dispelled any reservations about the model's legitimacy and the utility of applying it to predict the likelihood of bankruptcy in a company. The findings of this study have significant consequences for investors, creditors, and corporate management. Portfolio managers may make better selections by not investing in companies that have proved to be in danger of failing if they understand the variables that contribute to corporate distress.