• 제목/요약/키워드: DOE-2

검색결과 373건 처리시간 0.031초

부분부하 특성을 고려한 열원기기의 운전성능 평가 (EA Study on the Operation Performance of Central Plant Equipment According to Part Load Characteristics)

  • 이왕제;강은철;이의준;오병칠;신우철
    • 설비공학논문집
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    • 제25권7호
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    • pp.392-397
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    • 2013
  • To fulfill the demands concerning energy efficiency for zero energy buildings, various technologies of architects and engineers are required. This study aims to estimate the thermal performance of heat source equipment in which part load characteristics are considered in an office building. Overestimation of heat source equipment was reviewed through literature survey, and heating and cooling loads depending on the capacity and division of the equipment were analyzed through a simulation program (DOE-2.1E). The conclusions gained from this study are as follows; 1) The more the division of equipment, the less the heating and cooling energy consumption. 2) When a large item of equipment is divided into two small items of equipment, the optimum application rate showed as 5:5 for chiller, and 7:3 for boiler, respectively.

전화모니터링이 심부전 환자의 증상경험과 자기관리 이행정도에 미치는 효과 (Effect of a Telephone Monitoring on Self-management & Symptom Experiences in Patients With Heart Failure)

  • 송은경
    • 성인간호학회지
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    • 제17권1호
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    • pp.56-67
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    • 2005
  • Purpose: The main purpose of this study was to examine the effectiveness of a standardized telephone monitoring intervention in addressing the symptom experience and improving self-management ability in patients with heart failure. Methods: A non-equivalent control group pre-post test design was used. There were 17 patients in the experimental group, and 16 in the control group. According to the protocol, patients in the experimental group received 15 to 30 minute-telephone monitoring four times, once a week for 4 weeks. Data were analyzed by ${\chi}^2$-test, Mann-Whitney U test. Results: 1) The experimental group showed a significant increase in compliance with self-management compared to the control group. 2) There was a significant decrease in degree for 3 symptoms(DOE, PND, & continuing fatigue) in the experimental group, after telephone monitoring. However, the experimental group did not show significant decrease in the degree of the total symptom experiences. Conclusions: The results of this study provide evidence that standardized telephone monitoring is effective in relieving symptom experience and improving self-management in patients with heart failure over the course of telephone monitoring.

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Shroud 형상에 대한 해석적 연구 및 '프로벨러 홴' 소개 (Computational Study of the Shr oud Shape & the ProBeller Fan)

  • 한재오;유승훈;모진용
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.638-641
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    • 2008
  • Computational investigation was conducted to study the effects of the shape parameter of shroud on the performance of the outdoor unit of an air-conditioners. For this study the Design of Experiment(4-factor 3-level) was created and the an automatic program was composed using VBA to reduce the load of pre-process for CFD. The estimated mathematical equation was produced from this analysis and it was found that the gap between fan and shroud affects more heavily than the other parameters. As a result, the composition of the best parameters was verified that its flow rate was increased by 10 percents and sound pressure level was reduced by 1.2 dBA compare with the worst. And finally, a kind of Propeller fan with blades which were attached to the shroud, so-called 'ProBeller Fan' was introduced in this study.

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경구 Corticosteroid계 약물 치료한 환자에 있어서 혈중 cortisol에 관한 연구 (Study on Blood Cortisol in Patients treated with Oral Corticosteroid Drugs)

  • 박정희;김기황;유형식;이종태;박창윤;유경자
    • 대한핵의학회지
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    • 제14권1호
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    • pp.23-28
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    • 1980
  • This is an analysis of 32 patients who received long continuous corticosteroid drug due to some diseases. Patients were collected from June 1976 to March 1980. Blood cortisol level, variation of diurnal rhythm and side effects were studied. The Result as follows: 1. Side effects were observed in 24 patients(75%) and most common complaint was obesity. 2. Diurnal rhythm analysed by Doe's method shows abnormal diurnal rhythm is 21 out of 32(66%). 3. Mean durations or therapy of abnormal diurnal rhythm and normal diurnal rhythm were $55.7{\pm}4.4$ months and $43.9{\pm}7.0$ months respectively which shows statistically significant difference. 4. Mean cortisol value of steroid treated patients were lower than normal. 5. Reverse diurnal rhythm was 4 out of 21 patients. 6. 8 A.M. cortisol value is lower than 2 times of 8 P.M. in all patients who showed abnormal diurnal rhythm except one.

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좌석안전띠 부착장치 위치에 따른 어린이 충돌안전성 연구 (The Study on the Effect of Seatbelt anchorage points using Q6 in sled test)

  • 김시우;류현;김용길;백선현;김민우;박지훈
    • 자동차안전학회지
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    • 제6권2호
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    • pp.49-54
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    • 2014
  • Development in vehicle industry could increase interest in children's safety recently. However the research of children safety is not being conducted as many as that of adult's. Especially the basic study for the vehicle crash on-board children was not much. This study focused on the effect of seatbelt anchorage points to evaluate children's safety in frontal crash. The current regulation of the seatbelt anchorage points is suitable for ranged from female 5% to male 95%. The assessment of children's safety at buckle up of no used CRS(child restraint system) was performed using frontal sled tests. The frontal crash pulse in sled tests was designed to the average of about 30 KNCAP frontal crash pulses. To reduce number of experiments, DOE is used. The Q6 child dummy and standard seat in UN R 129 were used. According to the analysis of test results, children's safety has been influenced by the points of seatbelt anchorage.

Transient Increase of Lipocortin 1 in Nuclei of the Hippocampal Pyramidal Neurons in Rats Induced by Immobilization Stress

  • Park, Hyoung-Sup;Jang, Yeon-Jin;Kim, Dong-Hou;Lee, Su-Ok;Na, Doe-Sun
    • BMB Reports
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    • 제31권2호
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    • pp.117-122
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    • 1998
  • Changes of lipocortin 1 (LC1) in the brain induced by immobilization stress were investigated in rats. Rats were immobilized for 0,1,2,3,4, and 5 h, and the brain slices were immunostained with anti-human LC1 antibodl (anti-LC1). Immunoreactivity of LCI (iLC1) was most prominent in neuronal cell bodies and processes of hippocampal CA regions and dentate gyrus. At rest without stress, most of the LC1 in the neuron located in the cytoplasm with the nuclei exhibiting relatively scarce immunoreactivity. Immobilization stress changed this intracellular distribution of LC1 by increasing nuclear LC1. The change was apparent in 1 h and reached the peak by 3 h. However, by 5 h of immobilization, the distribution pattern returned to that of the resting state. This transient nuclear translocation of LC1 was most prominent in $CA_1$ pyramidal neurons, and was not observed in areas other than the hippocampus. Adrenalectomy abolished this transient translocation of LC1. The roles of hippocampal LC1 as a mediator of glucocorticoid feedback signal and/or as an intracellar stress signaling protein could be suggested.

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레이저 소결 적층 시스템과 실험 계획법을 이용한 3차원 바이오 세라믹 인공지지체의 제작 (Fabrication of 3D Bioceramic Scaffolds using Laser Sintering Deposition System and Design of Experiment)

  • 이창희;사민우;김종영
    • 한국기계가공학회지
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    • 제18권12호
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    • pp.59-66
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    • 2019
  • In this study, we developed a novel laser sintering deposition system (LSDS) based on solid free-form fabrication (SFF) technology as it has the potential to fabricate complex geometries with controllable architecture for bone tissue engineering applications. The 3D biphasic calcium phosphate (BCP) scaffolds were fabricated with a pore size of 800㎛, a line width and height of 1000㎛, and an overall size of 8.2×8.2×8.0 mm3 according to the design of experiment (DOE) results. Additionally, an optimized manufacturing process using response surface analysis was established to fabricate 3D BCP scaffolds. The fabricated 3D BCP scaffolds were sintered at 950℃, 1050℃, 1150℃, and 1250℃ according to sintering processes with a furnace. As the sintering temperature increased, the porosity increased. Through the compressive strength test, the 3D BCP scaffolds sintered at 1050℃ presented good results of about 0.76 MPa. These results suggest that fabrication methods for 3D bioceramic scaffolds using LSDS may meet the basic requirements for bone tissue engineering.

축류펌프 안내깃의 성능 향상을 위한 수치해석적 연구 (A Numerical Study on the Performance Improvement of Guide Vanes in an Axial-flow Pump)

  • 박현창;김성;윤준용;최영석
    • 한국유체기계학회 논문집
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    • 제15권6호
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    • pp.58-63
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    • 2012
  • This paper presents a numerical study on the performance improvement of axial-flow pump with guide vanes. Design optimization for guide vanes in an axial-flow pump has been studied through the implementation of a commercial CFD code and DOE (design of experiments). We also discussed how to improve the performance of the axial-flow pump by designing the guide vanes. Geometric design variables were defined by the meridional plane and vane plane development of guide vanes. The effect of hub tip ratio analyzed the meridional plane of guide vanes. The importance of the geometric design variables was analyzed using $2^k$ factorial designs. The objective functions for guide vane geometric variables were defined as the total efficiency and the total head at the design flow rate. From the $2^k$ factorial design results, the important design variables were found and the performance was increased in comparison with the base design model.

Sensitivity Analysis of Steering Wheel Return-ability at Low Speed

  • Cho, HyeonSeok;Lee, ByungRim;Chang, SeHyun;Park, YoungDae;Kim, MinJun;Hwang, SangWoo
    • 한국자동차공학회논문집
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    • 제25권2호
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    • pp.167-178
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    • 2017
  • The steering wheel of a vehicle has a typical characteristic of automatically returning to its neutral state when the driver releases it. Steering returnability originated from the tire forces and kingpin moments. It is proportional to the reaction torque that is generated through the rack and column, which are dependent on suspension and steering geometry. It is also important to accurately predict and design it because steering returnability is related to steering performance. In this study, a detailed multibody dynamics model of a vehicle was designed by using ADAMS/Car and simulated for steering returnability. In addition, a tolerance analysis of the chassis system in terms of part dimension and properties has been performed in order to minimize the design parameters. The sensitivity of the selected design parameters was then analyzed via Design of Experiments(DOE). As a result, we were able to obtain the main parameters through a contribution analysis. It can be used to predict steering returnability and improve its performance, which is represented by the angle of restoration and laterality.

Experimental analysis and modeling of steel fiber reinforced SCC using central composite design

  • Kandasamy, S.;Akila, P.
    • Computers and Concrete
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    • 제15권2호
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    • pp.215-229
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    • 2015
  • The emerging technology of self compacting concrete, fiber reinforcement together reduces vibration and substitute conventional reinforcement which help in improving the economic efficiency of the construction. The objective of this work is to find the regression model to determine the response surface of mix proportioning Steel Fiber Reinforced Self Compacting Concrete (SFSCC) using statistical investigation. A total of 30 mixtures were designed and analyzed based on Design of Experiment (DOE). The fresh properties of SCC and mechanical properties of concrete were studied using Response Surface Methodology (RSM). The results were analyzed by limited proportion of fly ash, fiber, volume combination ratio of two steel fibers with aspect ratio of 50/35: 60/30 and super plasticizer (SP) dosage. The center composite designs (CCD) have selected to produce the response in quadratic equation. The model responses included in the primary stage were flowing ability, filling ability, passing ability and segregation index whereas in harden stage of concrete, compressive strength, split tensile strength and flexural strength at 28 days were tested. In this paper, the regression model and the response surface plots have been discussed, and optimal results were found for all the responses.