• Title/Summary/Keyword: Inactive Design

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Shape Optimization of Cut-Off in Multiblade Fan/Scroll System Using CFD and Neural Network (신경망 기법을 이용한 다익 홴/스크롤 시스템의 컷오프 최적화)

  • Han, S.Y.;Maeng, J.S.;Yoo, D.H.
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.365-370
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    • 2001
  • In order to minimize unstable flow occurred at a multiblade fan/scroll system, optimal angle and shape of cut-off was determined by using two-dimensional turbulent fluid field analyses and neural network. The results of CFD analyses were used for learning as data of input and output of neural network. After learning neural network optimization process was accomplished for design variables, the angle and the shape of cut-off, in the design domain. As a result of optimization, the optimal angle and shape were obtained as 71 and 0.092 times the outer diameter of impeller, respectively, which are very similar values to previous studies. Finally, it was verified that the fluid field is very stable for optimal angle and shape of cut-off by two-dimensional CFD analysis.

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Static analysis of eddy current brake′s frame for design evaluation (와전류 제동장치 프레임 설계검토를 위한 강도해석)

  • Chung, Kyung-Ryul;W. Mantsch
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.317.1-317
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    • 2002
  • In this paper, static analysis of eddy current brake′s frame, which is one of key structural components of brake system for high speed train, was performed in order to evaluate the design by computer simulation. Calculation was carried out in general for the driving modes "braking" and "frame in upper position(brakes inactive)". Several yield stress load cases and fatigue load cases were analysed fur each of the driving modes. (omitted)

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Multi-level Optimization for Orthotropic Steel Deck Bridges (강바닥판교의 다단계 최적설계)

  • Cho, Hyo-Nam;Chung, Jee-Sung;Min, Daee-Hong;Lee, Kwang-Min
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.04b
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    • pp.439-448
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    • 2000
  • A multi-level design synthesis (MLDA) algorithm for efficiently optimizing orthotropic steel deck bridges is proposed in the paper, because it is usually very difficult to optimize orthotropic steel deck bridges using a conventional single-level (CSL) algorithn since the bridges have a large number of members and show complex structural behaviors. In the proposed MLDS algorithms a coordination method is introduced to divide the bridges into main girders and orthotropic steel decks and decomposition method is also used to reduce the number of design variables of the decks for system level optimization. For efficient optimization of the bridges the MLDS algorithm incorporates the crucial approximation techliques such as constraints deletion and stress reanalysis. The constraint deletion technique for deflection is found to be very useful for the optimization problem of the bridges, since a deflection constraint is usually inactive in the design. Considering the complex system of the bridges, the proposed the efficient stress reanalysis technique may prove to be a very effective method, since it does not require expensive design sensitivity analyses. The applicability and robustness of the MLDS algorithm is demonstrated using various numerical examples and compared with other algorithm presently available so far.

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Effects of a Sensory Stimulation on Weight, Stress Hormone and Behavioral State in Premature Infants (감각자극이 미숙아의 체중, 스트레스호르몬 및 행동상태에 미치는 효과)

  • 이군자
    • Journal of Korean Academy of Nursing
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    • v.29 no.2
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    • pp.445-455
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    • 1999
  • This study has been conducted on the nonequivalent control group pretest-posttest design in quasi experimental basis and newly born premature infants from intensive care unit of G Medical University Hospital in Inchon Metropolitan were selected in two groups of 21 infants each. The first group for experimental and the other for control. Data has been collected form October 30, 1997 to August 29, 1998. For the experimental group tactile and kinesthetic stimulation was applied 2 times a day for 10 days(10 : 00~11 : 00 hours in the morning and 17 : 00~18 : 00 in the afternoon). As a weight weighing instrument. electronic indicator scale(Cas Co. korea) was used. To determine urine cortisol concentration level in stress hormone, radio immune assay method was used. And high performance liquid chlomatography was used to determine urine norepinephrine, concentration level To determine behavior status, tools developed by Anderson et at(1990) and remodeled by Kim Hee-Sook(1996) were used. Collected data were analyzed with the SAS program using x$^2$-test, student t-test, repeated measures ANOVA and paired t -test. The result were as follow. 1. As for the daily weight gain. the experimental group showed first change in weight and this group also showed higher weight in the average weight than the control group. Statistically, however, there was no significant factor between the two group. 2. The cortisol concentration in urine showed decrease in the experimental group norepinephrine concentration in urine showed increase in both experimental and control groups. No statistical significance was shown between the two groups. 3. In the aspect of behavior status. the experimental group showed statistical significance by showing inactive in the state of alert and conversion to a positive state than the control group. In conclusion, the sensory stimulation in this study showed a positive aspect through there was no statistical significance in the weight gain and urine stress hormone concentration. In the behavior status, there was statistical significance in the frequency of staying inactive in the state of alert and conversion to a positive state.

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Hibernation Structure Design of Wireless USB over IEEE 802.15.6 Hierarchical MAC Protocol (WUSB over IEEE 802.15.6 통합 MAC 프로토콜의 Hibernation 구조 설계)

  • Hur, Kyeong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1610-1618
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    • 2014
  • Wearable computer systems can use the wireless universal serial bus (WUSB) that refers to USB technology that is merged with WiMedia PHY/MAC technical specifications. In this paper, we focus on an integrated system of the wireless USB over the IEEE 802.15.6 wireless body area networks (WBAN) for wireless wearable computer systems supporting U-health services. And a communication structure that performs the hibernation for low power consumption is proposed for WUSB over IEEE 802.15.6 hierarchical protocol. In the proposed hibernation mechanisms, WUSB communications are permitted at each m-periodic inactive periods of WBAN superframes by using the WBAN information of Wakeup Period and Wakeup Phase message fields. In our performance evaluations, performances according to amount of WUSB traffic and Wakeup Periods are analyzed respectively to evaluate the effectiveness of proposed hibernation structure in WUSB over IEEE 802.15.6.

Numerical Optimization of a Multi-blades Centrifugal Fan for High-efficiency Design (원심다익송풍기의 고효율 설계를 위한 수치최적설계)

  • Seo, Seoung-Jin;Kim, Kwang-Yong
    • The KSFM Journal of Fluid Machinery
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    • v.7 no.3 s.24
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    • pp.32-38
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    • 2004
  • Shape of a multi-blades centrifugal fan is optimized by response surface method based on three-dimensional Navier-Stokes analysis. For numerical analysis, Reynolds-averaged Navier-Stokes equations with standard $k-{epsilon}$ turbulence model are transformed into non-orthogonal curvilinear coordinate system, and are discretized with finite volume approximations. Due to the large number of blades in this centrifugal fan, the flow inside of the fan is regarded as steady flow by introducing the impeller force models for economic calculations. Optimizations with and without constraints are carried out. Design variables, location of cur off, radius of cut off, expansion angle of scroll and width of impeller were selected to optimize the shapes of scroll and blades. Data points for response evaluations were selected by D-optimal design, and linear programming method was used for the optimization on the response surface. As a main result of the optimization, the efficiency was successfully improved. The correlation of efficiency with relative size of inactive zone at the exit of impeller is discussed as well as with average momentum fluxes in the scroll.

A Study on Characterization of Apartment Complex Exterior Space by Purpose and Type - On Matters of Apartment Complexes Built·Redeveloped Since Year 2005 in Seoul - (공동주택 외부 공간의 유형(類型)에 따른 특성화에 관한 연구 - 2005년 이후, 서울시 재건축·재개발된 공동주택 외부 공간 사례 중심으로 -)

  • Yi, Young-Ran;Chu, Beom
    • Korean Institute of Interior Design Journal
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    • v.22 no.4
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    • pp.130-140
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    • 2013
  • As the modern-day Apartment Complex has varied community facilities such as health care center and self-improvement institutions affecting the residents' quality of life, this paper is for the in-depth understanding on how such Exterior Space vary and development plan should go. To be specific, this paper is to, based upon the theoretical contemplation on the concept and role of the Exterior Space to Apartment Complex, as well as drawing a conclusion on the development plan for subject areas as assessed. Subject areas of this paper are a total of twelve Apartment Complexes built since Year 2005 in nine different regions in Seoul. As such specialties and features as leisure of the senior citizen and female residents, the subject Apartment Complexes have provided opportunities, active and inactive, to the residents for leisure by qualitative improvement of facilities, as well as establishing the discrete brand value for the Exterior Space with featured design and spatial properties. Also notable is the eco-friendliness of the Exterior Space with cutting-edge technology, eventually appreciating the value of Apartment Complex.

A Study on Affordance Dimensions of Digital Services for the Elderly through the Analysis of Senior Adults' Daily Activities

  • Park, Soobeen
    • Architectural research
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    • v.10 no.2
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    • pp.11-20
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    • 2008
  • Designing environments for the elderly includes studying changes in the elderly themselves, changes in their environment, and changes in the intercommunication between the elderly and their environment. The purpose of this study is to provide guidelines for a ubiquitous environment in which seniors can "age in place," using an environment-behavioral approach. 305 subjects aged 45 to 78 take part in the survey research. Temporal sequence (age groups) and behavior (daily activities) are considered as the significant variables to design digital services for the elderly in the perspective of an environment-behavioral approach. Several conclusions can be made. (1) The characteristics of subjects in the over-65 age group shows that they manage an independent lifestyle even if they realize some body functions deteriorate as they age. (2) Over-65 age group is more engaged in healthcare and pastime activities. The male subjects of it are most inactive. (3) The IDA (importance of daily activities) and FDA (frequency of daily activities) are classified by five to six factors in each group. The IDA and FDA of the group aged over 65 differ from other age groups. (4) Five affordance dimensions of digital services for the elderly are proposed: Healthcare, Domesticity, Mobility & Security, Network, and Recreation & Pastime. These affordance dimensions will help research groups or companies design ubiquitous environments to enhance the quality of life of seniors.

Numerical Optimization of A Multi-Blades Centrifugal Fan For High-Efficiency Design (원심다익송풍기의 고효율 설계를 위한 수치최적설계)

  • Seo, Seoung-Jin;Kim, Kwang-Yong
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.385-390
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    • 2003
  • Shape of a multi-blades centrifugal fan is optimized by response surface method based on three-dimensional Navier-Stokes analysis. For numerical analysis, Reynolds-averaged Wavier-Stokes equations with standard $k-{\varepsilon}$ turbulence model are transformed into non-orthogonal curvilinear coordinate system, and are discretized with finite volume approximations. Due to the large number of blades in this centrifugal fan, the flow inside of the fan is regarded as steady flow by introducing the impeller force models for economic calculations. Optimizations with and without constraints are carried out. Design variables, location of cur off, radius of cut off, expansion angle of scroll and width of impeller were selected to optimize the shapes of scroll and blades. Data points for response evaluations were selected by D-optimal design, and linear programming method was used for the optimization on the response surface. As a main result of the optimization, the efficiency was successfully improved. The correlation of efficiency with relative size of inactive zone at the exit of impeller is discussed as well as with average momentum fluxes in the scroll.

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The Compound Effect of Cupping Therapy: Searching Beyond the Meridians

  • Khalil, Mohamed K.M.;AlSanad, Saud
    • Journal of Acupuncture Research
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    • v.35 no.3
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    • pp.101-103
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    • 2018
  • Cupping therapy (CT) is used in Asia, Europe, and the Middle East and is prevalent in Muslim communities where it is recommended by the Prophet of Islam. The majority of modern, medical practitioners interested in CT, view it as a medical technique and distance themselves from the mechanisms proposed by traditional medicine. However, modern medicine does not offer a valid explanation for the mechanisms involved in CT. There is growing evidence of CT's effectiveness, specifically in chronic pain management when compared to an inactive control, but not against sham treatment. CT accompanied by religion and prayer, as it is in Muslim communities, cannot be considered to be equivalent to any procedures in modern medicine. "Whole System Research" may be the most appropriate trial design to test the ancient practice of CT efficacy whilst pending development of a novel placebo for assessing the connectivity of body and mind interventions.