• 제목/요약/키워드: flow management

검색결과 3,545건 처리시간 0.032초

가정용 무선 호흡기류 및 요속신호 계측 시스템 개발 (Development of Wireless Respiratory Air Flow and Urinary Flow Measurement System for Home Healthcare)

  • 차은종;이인광;이유미;한순화;한정수;서재원;박찬식;김경아
    • 전기학회논문지
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    • 제61권9호
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    • pp.1350-1357
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    • 2012
  • Medical system for personal health management recently changes its paradigm from hospital service to self home care based on ubiquitous technology for healthcare anywhere at any time. The present study developed a wireless bio-signal measurement system for patients to self manage pulmonary disease and benign prostate hyperplasia(BPH), both of which are chronic diseases with increasing frequency in modern society. Velocity-type respiratory air flow transducer adapted to develop respiratory module for pulmonary disease management was simplified in structure to measure uni-directional flow since most important diagnostic parameters are evaluated on the expiratory flow signal only. Standard weight measurement technique was introduced to obtain urinary flow signal for BPH management. Three load cell signals were acquired for averaging to minimize noise, followed by accuracy evaluation. Transmission and receiver modules were also developed with user program for wireless communication. Averaged relative errors were 2.05 and 1.02% for respiratory volume and maximal flow rate, respectively, and the relative error was 2.17% for urinary volume, demonstrating that both modules enabled very accurate measurements. Wireless communication distance was verified within 15m, long enough for home care application. The present system allows the user to select a necessary measurement module on a particular health demand and to immediately provide the self-test results, thus better quality health care would be possible.

항공 Lidar 자료와 지형복원기법을 이용한 토석류 토사변화 공간분포 추정 (Estimation of Spatial Soil Distribution Changed by Debris Flow using Airborne Lidar Data and the Topography Restoration Method)

  • 우충식;윤호중;이창우;이규성
    • 한국산림과학회지
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    • 제101권1호
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    • pp.20-27
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    • 2012
  • 토석류 발생으로 유출된 토사량은 발생 전 후의 항공 Lidar 지형자료의 차이로부터 간단히 추정할 수 있지만, 토석류는 산지에서 발생하고 항공 Lidar 자료는 주로 도시지역에 집중되어있어 토석류의 발생이전 정밀지형자료를 이용하는 것은 어렵다. 이러한 이유로 우충식(2011)은 토석류 발생이후 촬영된 항공 Lidar 자료를 이용하여 토석류 발생이전의 지형을 추정할 수 있는 지형복원기법을 개발하였다. 본 연구에서는 토석류 발생지역인 인제, 봉화, 제천지역에 지형복원기법을 적용하여 RMSE가 0.16~0.34 m인 토석류 발생전 지형자료를 제작하였다. 또한 토석류 발생 전 후의 토사변화량을 분석하였고, 토석류 유동시 나타나는 침식, 유하, 퇴적작용의 공간분포와 하류에 실제 유출된 토사량을 추정하였다.

The Impact of Operating Cash Flows on Financial Stability of Commercial Banks: Evidence from Pakistan

  • ELAHI, Mustahsan;AHMAD, Habib;SHAMAS UL HAQ, Muhammad;SALEEM, Ali
    • The Journal of Asian Finance, Economics and Business
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    • 제8권11호
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    • pp.223-234
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    • 2021
  • This study aims to examine whether operating cash flows influence banks' financial stability in Pakistan. The study employed annual panel data collected from annual reports of 20 commercial banks listed on the Pakistan Stock Exchange for the year 2011 to 2019. Free cash flow yield was taken as the dependent variable while cash flow ratio was selected as the independent variable, and net interest margin, income diversification, asset quality, financial leverage, the cost to income ratio, advance net of provisions to total assets ratio, capital ratio, financial performance, breakup value per share and bank size were taken as control variables. The study performed ordinary least square technique, random and fixed effects models, Hausman test, Lagrange multiplier test, descriptive and correlation analysis. Results showed that operating cash flows and net interest margin significantly and positively influenced banks' financial stability while the cost to income ratio and advances net of provisions to total assets ratio significantly and negatively associated with banks' financial stability. To improve financial stability, banks should become more cost-effective and enhance their liquidity levels by lowering lending activities. In the future, it would be useful to compare commercial and investment banks, also Islamic and conventional banks in the same research setting.

Free Cash Flow, Agency Conflicts, and Compensation Plans in a Non-growing Industry

  • Park, Sang-Bum
    • 재무관리논총
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    • 제10권1호
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    • pp.249-269
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    • 2004
  • Free cash flow is known as a typical type of agency conflict between managers and shareholders in a firm. The insurance industry, which is not growing, is particularly susceptible to such excessive cash flow. We herein investigate the effects of stock ownership plans on reducing agency conflicts. We adopt undistributed cash flow to proxy free cash flow, and size, default risk, group membership, leverage, investment opportunity, and stock options are selected as explanatory variables. We find that stock option plans are effective(at a 10% level) in reducing free cash flow.

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2차원 수치모형을 이용한 수공구조물 설치에 따른 수리학적 흐름 영향 평가 (Assessment for Characteristics of Flow According to Installing Hydraulic Structures by 2-D Numerical Model)

  • 최승용;남기영;한건연
    • 환경영향평가
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    • 제20권6호
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    • pp.797-813
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    • 2011
  • Frequently occurring flood and drought due to abnormal climate and global warming have increased the necessity of an effective water resources control and management of river flows. The various hydraulic structures are constructed in river as part of an effective water resources management. It is very important to analyse characteristics of flow according to installing hydraulic structures in this situations. The objective of this study is to investigate the hydraulic behaviors of flow considering affections of hydraulic structures using 2-D numerical model. To do this, both RMA-2 model and developed RAM2 model are used to analyse flow phenomena before and after installation of hydraulic structures in Nakdong river. As a result of, the water surface elevation at upstream regions increased about 22cm~66cm and the velocity around the structures sharply increased after installation of structures. The measures for the rise of water surface at upstream and local scour due to high velocity around the structures must be established when the structures is constructed.

네트워크 문제 해결에 있어서 효과적인 pricing 방법에 관한 연구 (An Efficient Pricing Strategy(PAPANET) for Solving Network Flow Problems)

  • Kang, Moonsig
    • 한국경영과학회지
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    • 제27권2호
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    • pp.153-171
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    • 2002
  • In this paper, we present an efficient pricing strategy, the pivot and probe Algorithm for Network Flow Problems(PAPANET), specifically for solving capacitated, linear network flow problem (NPs). The PAPANET begins with an initial relaxed network problem(RNP), consisting of all the nodes and initial candidate arcs(possibly a few least cost arcs form the original problem and a set of all the artificial and slack arcs). After an initial solution to the RNP is derived by pivoting, the PROBE procedure identifies a set of most violated arcs from the noncandidate arcs that are not considered to be in the current RNP, and adds them to the RNP. The procedure also discards a set of least favorable, zero flow, nonbasic arcs from the RNP. The new RNP is solved to optimality and the procedure continues until all of the dual constraints of the noncandidate arcs are satisfied by the dual solution to the RNP. The PAPANET effectively reduces the problem size, time per pivot, and solution CPU time by eliminating noncandidate arcs. Computational tests on randomly generated problems indicate that PAPANET achieves and average savings of 50-80% of the solution CPU time of that of a comparable standard network simplex implementation.

고분자전해질형 단위 연료전지의 주요 작동 조건이 공기극 플러딩 현상에 미치는 영향 (Effect of Main Operating Conditions on Cathode Flooding Characteristics in a PEM Unit Fuel Cell)

  • 민경덕;김한상
    • 대한기계학회논문집B
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    • 제30권5호
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    • pp.489-495
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    • 2006
  • Proton exchange membrane (PEM) should be sufficiently hydrated with a careful consideration of heat and water management. Water management has been a critical operation issue for better understanding the operation and optimizing the performance of a PEM fuel cell. The flooding on cathode side resulting from excess water can limit the fuel cell performance. In this study, the visual cell was designed and fabricated fur the visualization of liquid water droplet dynamics related to cathode flooding in flow channels. The experiment was carried out to observe the formation, growth and removal of water droplets using CCD imaging system. Effects of operating conditions such as cell temperature, air flow rate and air relative humidity on cathode flooding characteristics were mainly investigated. Based on this study, we can get the basic insight into flooding phenomena and its two-phase flow nature. It is expected that data obtained can be effectively used fur the setup and validation of two-phase PEM fuel cell models considering cathode flooding.

공공도서관의 서비스스케이프가 고객충성도에 미치는 영향에 관한 연구 (A Study on the Effect of Public Library Service Scape on Customer Loyalty)

  • 김영희;조동혁
    • 품질경영학회지
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    • 제51권1호
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    • pp.19-36
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    • 2023
  • Purpose: The purpose of this study is to empirically verify the structural relationship between public library service-scape, flow, user satisfaction, and customer loyalty for adults who use public libraries for academic purposes in a changing public library environment. To this end, this study reviewed the concepts of public library service-scape, immersion, user satisfaction, and customer loyalty with existing literature, proposed a research model based on this, and empirically verified them. Methods: This study collected and statistically analyzed data for adults using public libraries for the purpose of reading books or studying. The collected data were checked using SPSS 24.0 and AMOS 24.0 and the research hypothesis was verified by analyzing the results using the structural equation modeling technique. Results: The results of the study are as follows. First, spatiality, aesthetics, and amenity of service-scapes have a positive effect on flow. Second, spatiality and amenity of service-scapes have a positive effect on user satisfaction. Third, Flow has a positive effect on user satisfaction. Fourth, Flow and user satisfaction have a positive effect on customer loyalty. Conclusion: This study is meaningful in that it suggests a strategic direction to enhance the service competitiveness of public libraries by strengthening the service-scape.

SUPPLY CHAIN MANAGEMENT SYSTEM FOR CURTAIN WALLS USING RFID TECHNOLOGY

  • Sangyoon Chin;Suwon Yoon;Yea-Sang Kim;Cheolho Choi;Do-Bum Lee
    • 국제학술발표논문집
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    • The 1th International Conference on Construction Engineering and Project Management
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    • pp.1022-1027
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    • 2005
  • This research presents a collaborative supply chain management system for curtain walls using Radio Frequency IDentification (RFID) to track the product and information flow among participants in high-rise building construction projects. This resarch developed a process model and a strategy for effective utilization of RFID technology through the curtain wall life-cycle. Then an information management system was developed to support the supply chain management of curtain walls with incorporating RFID into curtain wall products flow throughout the life-cycle. The system has been tested for validation and verification in a real world project.

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한강에서의 하천유지유량 산정 (Estimation of Instream Flow in Han River)

  • 오규창;정상만
    • 물과 미래
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    • 제24권1호
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    • pp.119-128
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    • 1991
  • 본 연구는 하천유지유량의 개념을 정립하여 기존의 하천유지유량 개념의 모호성 및 산정방법의 차이에서 오는 문제점을 방지하기 위한 것이다. 평균갈수량은 하천의 건천화 방지 등의 기능을 유지하기 위하여 하류에 흐르도록 보장해 주어야 할 유량으로 규정하였으며 환경보존유량은 하천환경의 적절한 보존을 위하여 주운, 염해 방지, 하천관리시설의 보호, 수질보전, 어업, 하구폐쇄의 방지, 지하수위의 유지, 동식물의 보호, 경관등에 필요한 유량으로 규정하였다. 이를 위하여 한강의 인도교 지점을 선정하여 유황분석을 실시하였으며 각 지점에 대하여 자연상태하의 평균갈수량을 산정하였다. 위에서 언급한 하천환경보존에 관련된 9가지 기능을 종합적으로 고려한 결과, 현재로서는 수질보전이 환경보존유량의 가장 중요한 기능으로 파악되었으며 유역에서 발생되는 오염부하량과 하천에 유입되는 오염부하량을 산정하고 이에 따른 주요 지점의 장래수질을 예측하였다. 또한 예측된 장래수질과 환경기준을 비교하여 인도교 지점의 적정회석유량을 산정하였다. 산정된 평균갈수량과 환경보존유량은 비소비성 유량이므로, 이 두 유량에서 큰 것을 택한 유량, 즉 Max. (평균갈수량, 환경보존 유량)을 하천유지유량으로 산정 제시하였다. 이 유량에 하류의 유수점용을 위하여 필요한 양, 즉 소비성 유량인이 수유량을 더하면 하천관리의 기준이 되는 하천관리유량을 설정할 수 있다. 본 연구결과는 한강뿐만 아니라 그 외의 주요 하천에 대해 체계적인 하천 관리를 수행하는데 기본 자료로서 크게 이바지 할 것으로 기대된다.

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