• Title/Summary/Keyword: Flow Field analysis

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Decision Making Support System for Water Supply Facilities Planning using Geographic Information System (GIS를 이용한 상수도(上水道) 계획(計劃) 의사결정(意思決定) 지원(支援)시스템 연구(硏究))

  • Ha, Sung-Ryung;Kim, Ju-Hwan
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.2 s.6
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    • pp.101-113
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    • 1995
  • In pipeline planning, the systematic and reasonal management of topographical and spatial data are needed in order to omprove the availibilities for data analysis and the effective combinations of spatial informations. According to that fact, DBMS (Database Management System) and DSS(Decision making Support System) have to be developed for the planning of water supply system Also, the economic selection for harmonious delivery of water to target area, since the alternatives of pre-designed pipeline are influenced by hydraulic stability and geographic characteristics. In this study, GIS technique for water supply planning and management which stores graphic features and attributes as digital data sets is considered and engineering application programs are integrated for effective planning of water supply system. Decision making support system based on analyzing technical, Social and economical aspects is developed for the extension of water supply facilities and pipeline configurations. Especially, Hydraulic, land-use and economic influences are considered as important factors for the purpose of developing the system. Hydraulic analysis program(SAPID) for pipeline flow which is already developed in Water Resources Research Institute and economic analysis program(ECOVEL) are integrated with GIS for resonable decision making. Every possible aspects in pipeline planning for water supply is reviewed and the applicabilities of developed system into the field are evaluated.

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A Study of Expressway Tollbooth Metering Effect (고속도로 영업소 미터링 효과에 관한 연구)

  • Im, Jin-Won;Yoon, Jae-Yong;Lee, Eui-Eun;Kim, Kwan-Min
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.1-10
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    • 2011
  • According to the worldwide efforts to reduce greenhouse gases consequent upon climatic change, the field of road traffic is also making diverse efforts to reduce the emissions of greenhouse gases. Among these, the exhaust gases from vehicles, the so-called main culprit of the greenhouse gases will take place the more as delay and tie-up of vehicles ever take place. Accordingly, as a scheme for reducing the delay & tie-up of vehicles, it's possible to bring up the idea of supply of new facilities and management of the existing facilities; recently, a lot more focus is being put on the management of the existing facilities due to enormous amounts of construction cost. In the midst of growing concern for traffic demand management policy, it's about the time we should do research on the tollbooth metering on the expressway whose research is almost non-existent home and abroad. As a traffic demand management policy coming to happen in case of the management of pay expressway like Japan and Korea, this research analyzed the contents of tollbooth metering, its effect and its subsequent convenience. Especially as a tool for effect analysis, this research made an analysis using VISSIM-a micro-simulation tool. As the tollbooth metering promoted, as a part of green traffic promotion strategy, is expected to contribute to improvement in traffic flow and reduction in carbon emissions, etc. It seems that there needs to be continuous research work on the management plan & revitalization plan for maximization of its effect later as well.

Nursing Knowledge/Power and Practice in Pediatric Intensive Care Unit (간호학적 지식/권력과 실무: 아동중환자실을 중심으로)

  • Lee Eun Joo;Hong Kyung Ja
    • Child Health Nursing Research
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    • v.7 no.1
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    • pp.85-95
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    • 2001
  • The purpose of this study was to reveal what influences the divergent methodological researches have brought the nursing practice in during the past 3 decades. The nursing record sheets ie, the nursing discourses were analyzed to know the knowledges that were recorded, accepted and communicated in nursing practice at pediatric intensive care units, and unclosed the philosophical and methodological position of that knowledges. The texts were 13 sheets, 3 kinds of nursing record(7 24hours flow charts, 4 nursing information record sheets and 2 transfer record sheets) used at 4 hospitals. The unit of analysis was 'word'. First, all words of the sheets were listed up, clustered into categories based on their contents. And then, the larger conceptual themes were drawn to elucidate the effect of the knowledge/power and the philosophical and methodological position of that knowledges. To enhanced the validity of the analysis, the data were analyzed by two researchers. The 'words' were classified into 3 categories; 'general information', 'assessment' and 'inter-vention'. The conceptual themes of the texts were 'the gaze for quantification and objectification' and 'technical/assimilated caring'. This themes reflected the logic positivistic and biomedical view that had dominated at clinical practice. Nursing has endeavored to resist the logic-positivistic knowledge/power and to established the nursing knowledge/power based on multiple philosophies and methodologies, especially phenomenological-interpretative. But the results of this study revealed that such efforts in nursing theory and research couldn't influenced the knowledge of practice. Logic positivism was yet so strong and the biomedical model yet dominated in the clinical practice. It identified that the borrowed theory and the knowledge from the received view gave nursing the power. But they were modalities that reinforced the dominant, medical power. Nursing has investigate the other positions (feminism, Habermas' critical social theory and Foucault's discourse theory). This positions suggest different assumptions but share the common concepts; equality, emancipation and freedom. The important point is how make these concepts the practical for nursing knowledge/power in practice. We must recognize that the praxis at clinical setting take place at the field unlike theoretical praxis. The change of clinical practice is the social, economic and political change.

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Three-Car following model parameter estimation and vehicle tinting impact analysis using time-space GPS data (시공간 GPS자료를 활용한 연속차량 3대의 차량추종모형 파라메터 추정과 차량틴팅의 영향분석)

  • Kim, Hye-Won;Lee, Chung-Won
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.6
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    • pp.15-23
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    • 2011
  • Driving directly in front of the driver of a vehicle driving in front of the vehicle and it is commonly known is affected. Responding to the car in front of the driver and the vehicle in front, and these follow the model is known as Three-Car-Following Model. Platoon vehicles to follow behind the driver's visibility is affected by the a tinted vehicle, and Parameters of the model is estimated to be affected also. In this study, in Three-Car-Followng Model parameters were estimated. and the parameter values differ about whether and how analysis was performed by the level of Visible Light Transmission Percentage. RTK GPS receiving data through field experiment analyzed based on sensitivity of three car by Visible Light Transmission Percentage and ${\gamma}$. And With statistical verification of driving directly in front of the driver in front of the vehicle and that the moving vehicle is influenced also confirmed. Also Visible Light Transmission Percentage is lowered, the vehicle in front of the driver's behavior showed sensitive reactions. In the further need to research for influence analysis of traffic flow capacity by the level of VLT.

Borehole Elemental Concentration Logs: Theory, Current Trends and Next Level (암석구성성분검층: 원리, 연구동향 및 향후 과제)

  • Shin, Jehyun;Hwang, Seho
    • Geophysics and Geophysical Exploration
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    • v.22 no.3
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    • pp.149-159
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    • 2019
  • Borehole elemental concentration logging, measuring neutron-induced gamma rays by inelastic scattering and neutron capture interactions between neutron and formation, delivers concentrations of the most common elements found in the minerals and fluids of subsurface formation. X-ray diffraction and X-ray fluorescence analysis from core samples are traditionally used to understand formation composition and mineralogy, but it represents only part of formations. Additionally, it is difficult to obtain elemental analysis over the whole intervals because of poor core recovery zones such as fractures or sand layers mainly responsible for groundwater flow. The development of borehole technique for in situ elemental analysis plays a key role in assessing subsurface environment. Although this technology has advanced consistently starting from conventional and unconventional resources evaluation, it has been considered as exclusive techniques of some major service company. As regards domestic research and development, it has still remained an unexplored field because of some barriers such as the deficiency of detailed information on tools and calibration facility for chemistry and mineralogy database. This article reviews the basic theory of spectroscopy measurements, system configuration, calibration facility, and current status. In addition, this article introduces the domestic researches and self-development status on borehole elemental concentration tools.

A Study on the Feasibility Analysis of AI CARE Design Graphic Planning through Modern Design Trend Analysis -Focusing on AI CARE BED part-by-part analysis and design proposal- (현대 디자인 트랜드 분석 통한 AI CARE 디자인 그래픽 기획에 관한 타당성 분석에 관한 연구 -AI CARE BED 파트별 분석과 디자인 제안을 중심으로-)

  • Cho, Hyun Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.3
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    • pp.599-604
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    • 2021
  • In an era where AI artificial intelligence converges into each field, design of AI-CARE function and UI UX design are in the spotlight. The application of shape design and the trend of color are important for visual effects to match new features. In this paper, we would like to use this to present an example of the arrangement and application of form trends and to present design directions. In the introduction, the latest design environmental factors were analyzed and studied in the direction of the new proposal. In the text, the design direction and consideration of the design in the planning were studied by separating the functional design form, and the direction of the design work was presented. At the stage of form and color, a plan was proposed to match the flow of minimalism, universal design, and affordance design. A study method based on case practice is a consideration of how to consider content on shapes and colors specialized in the partial design work, and proposed to enable graphic production of new areas of UI UX in content images to be feasible. Through this study, the design direction and planning of the derivative method of shape and color was reached by suggesting design directionality and validity for each AI CARE bed PART.

Analysis of Research Trends in Tax Compliance using Topic Modeling (토픽모델링을 활용한 조세순응 연구 동향 분석)

  • Kang, Min-Jo;Baek, Pyoung-Gu
    • The Journal of the Korea Contents Association
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    • v.22 no.1
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    • pp.99-115
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    • 2022
  • In this study, domestic academic journal papers on tax compliance, tax consciousness, and faithful tax payment (hereinafter referred to as "tax compliance") were comprehensively analyzed from an interdisciplinary perspective as a representative research topic in the field of tax science. To achieve the research purpose, topic modeling technique was applied as part of text mining. In the flow of data collection-keyword preprocessing-topic model analysis, potential research topics were presented from tax compliance related keywords registered by the researcher in a total of 347 papers. The results of this study can be summarized as follows. First, in the keyword analysis, keywords such as tax investigation, tax avoidance, and honest tax reporting system were included in the top 5 keywords based on simple term-frequency, and in the TF-IDF value considering the relative importance of keywords, they were also included in the top 5 keywords. On the other hand, the keyword, tax evasion, was included in the top keyword based on the TF-IDF value, whereas it was not highlighted in the simple term-frequency. Second, eight potential research topics were derived through topic modeling. The topics covered are (1) tax fairness and suppression of tax offenses, (2) the ideology of the tax law and the validity of tax policies, (3) the principle of substance over form and guarantee of tax receivables (4) tax compliance costs and tax administration services, (5) the tax returns self- assessment system and tax experts, (6) tax climate and strategic tax behavior, (7) multifaceted tax behavior and differential compliance intentions, (8) tax information system and tax resource management. The research comprehensively looked at the various perspectives on the tax compliance from an interdisciplinary perspective, thereby comprehensively grasping past research trends on tax compliance and suggesting the direction of future research.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

A Study on the Optimum Design of Multiple Screw Type Dryer for Treatment of Sewage Sludge (하수슬러지 처리를 위한 다축 스크류 난류 접촉식 건조기의 최적 설계 연구)

  • Na, En-Soo;Shin, Sung-Soo;Shin, Mi-Soo;Jang, Dong-Soon
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.4
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    • pp.223-231
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    • 2012
  • The purpose of this study is to investigate basically the mechanism of heat transfer by the resolution of complex fluid flow inside a sophisticated designed screw dryer for the treatment of sewage sludge by using numerical analysis and experimental study. By doing this, the result was quite helpful to obtain the design criteria for enhancing drying efficiency, thereby achieving the optimal design of a multiple screw type dryer for treating inorganic and organic sludge wastes. One notable design feature of the dryer was to bypass a certain of fraction of the hot combustion gases into the bottom of the screw cylinder, by the fluid flow induction, across the delicately designed holes on the screw surface to agitate internally the sticky sludges. This offers many benefits not only in the enhancement of thermal efficiency even for the high viscosity material but also greater flexibility in the application of system design and operation. However, one careful precaution was made in operation in that when distributing the hot flue gas over the lump of sludge for internal agitation not to make any pore blocking and to avoid too much pressure drop caused by inertial resistance across the lump of sludge. The optimal retention time for rotating the screw at 1 rpm in order to treat 200 kg/hr of sewage sludge was determined empirically about 100 minutes. The corresponding optimal heat source was found to be 150,000 kcal/hr. A series of numerical calculation is performed to resolve flow characteristics in order to assist in the system design as function of important system and operational variables. The numerical calculation is successfully evaluated against experimental temperature profile and flow field characteristics. In general, the calculation results are physically reasonable and consistent in parametric study. In further studies, more quantitative data analyses such as pressure drop across the type and loading of drying sludge will be made for the system evaluation in experiment and calculation.

Comparison for Glomerular Filtration Rate in Gamma Camera Systems Using Dynamic Renal Phantom System (동적신장팬텀시스템 개발에 따른 장비별 사구체여과율의 비교)

  • Kang, Chun Goo;Park, Hoon-Hee;Oh, Shin Hyun;Lee, Han Wool;Kim, Jung Yul;Oh, Joo Yung;Lee, Ju Young;Kim, Jae Sam;Lee, Chang Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.2
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    • pp.3-9
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    • 2013
  • Purpose: Currently commercially available phantom can reproduce and evaluate only a static situation, the study is incomplete research on phantom and system which is can confirmed functional situation in the kidney by time through dynamic phantom and blood flow velocity, various difference according to the amount of radioactive. Therefore, through this study, it has produced the dynamic kidney phantom to reproduce images through the dynamic flow of the kidney, it desire to evaluate the usefulness of nuclear medicine imaging. Materials and Methods: The production of the kidney phantom was fabricated based on the normal adult kidney, in order to reproduce the dynamic situation based on the fabricated kidney phantom, in this study it was applied the volume pump that can adjust the speed of blood flow, so it can be integrated continuously radioactive isotopes in the kidney by using $^{99m}Tc-pertechnate$. Used the radioactive isotope was supplied through the two pump. It was confirmed the changes according to the infusion rate, radioactive isotopes and the different injection speeds on the left and right, analysis of the acquired images was done by drawn ten times ROI in order to check the reproducibility of each on the front and rear of the kidney and bladder. Results: Under the same conditions infusion rate 40 mL/min fixed to adjust the pressure of the pump when the radiopharmaceuticals between 2-3 minutes in the most integrated in the kidney phantom was excreted inthe bladder. Glomerular filtration rate (GFR), respectively, by each device SYMBIA 1,091 mL/min, FORTE 1,232 mL/min, ARGUS 1,264 mL/min, INFINIA 1,302 mL/min in that there isno statistically significant difference was found, Tmax values and T1/2 values stars from all equipment with no statistically significant difference was found. CV values of the coefficient of variation less than 5% was found to be repeatable, and to 2.67% of the lowest SYMBIA appeared, INFINIA was the highest in the 4.86%. Conclusion: Through this study, the results showed that the dynamic kidney phantom system is able to similarly reproduce renogram in the actual clinical. Especially, the depicted over time for the flow to be excreted through the kidney into the bladder was adequately reproduce, it is expected to be utilized as basic data to check the quality of the dynamic images. In addition, it is considered to help in the field of functional imaging and quality control.

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