• Title/Summary/Keyword: blind

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Planning of the Blind Position Considering Thermal Performance in the Intermediate Space of Double-Skin Facade

  • Choi Dong-Hee;Jo Jae-Hun;Seok Ho-Tae;Yeo Myoung-Souk;Kim Kwang-Woo
    • International Journal of Air-Conditioning and Refrigeration
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    • v.14 no.2
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    • pp.57-65
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    • 2006
  • The blinds in the intermediate space are installed to block the direct solar radiation. As the blind divides the airflow of intermediate space into two parts, thermal performance of Double-Skin Facade(DSF) is affected by the blind position. Therefore the blind position should be planned with careful consideration in order to maximize the thermal performance of DSF. In this study, CFD was performed to analyze the effect of blind position in multistory-type DSF in variation of other DSF elements. The simulation results showed that the case with narrow depth of intermediate space and outlet on upper side of outer-facade, it is profitable to place blind as close as possible to the outer facade. In the other cases, the blind should maintain 0.15m distance from outer facade.

Optimum Blind Control Considering Characteristics of Solar Profile Angle Curve (건물에서 태양 프로파일의 변화 특성을 고려한 블라인드 최적 제어 방안)

  • Seong, Yoon-Bok
    • Journal of the Korean Solar Energy Society
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    • v.31 no.6
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    • pp.111-124
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    • 2011
  • The objective of this study is to develop the blind control strategy and method which reduce negative effect of incoming daylight on visual comfort of occupants, minimize psychological anxieties caused by frequent motions of a blind, and maximize positive effect of incoming daylight by opening/closing of a blind. In previous researches on blind controls, major problem is that the time interval and amount of blind movement do not meet the control objective at the inflected zone of solar profile curve. To overcome these limitations revealed in theprevious researches, following tasks were performed in this study. i)To establish the control objective to accomplish the goal of this study. ii)To develop the control methods and algorithms which prevent glare on the work-plane at any time and which control the time interval and amount of blind movement to follow the control objective at various solar profile angle curves. This study proposed the control strategy and method that define the base control section implying the inflection point within the control objective zone and subsequently, divide the control sections for the residual time zones. The proposed strategy and method are found to increase the incoming daylight and solar irradiation by 0 to 15 %.

The Study of Brain Function Changes After Contralateral and Ipsilateral Application Of Electroacupuncture (동측 및 대측 전침자극 전후의 뇌기능 변화에 관한 연구)

  • Woo, Young-min;Shin, Byung-cheul;Nam, Young
    • Journal of Acupuncture Research
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    • v.20 no.1
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    • pp.22-34
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    • 2003
  • Objective : To ascertain whether the concept of the treatment side is associated with changes in the blind spot mapping that represents the brain function. Methods : Among the outpatients who visited to Department of Acupuncture & Moxibustion, National Medical Center from March 2002 to October 2002, we selected 40 clinical trial volunteers that showed right side physiological blind spot more enlarged than left, and underwent the examinations of Department of Opthalmology, National Medical Center for ruling out the pathological conditions. Physiological blind spot maps were used as an integer of brain activity before and after electroacupuncture application on the unilateral ST36 meridian point by dividing 40 subjects into two comparative groups for double-blind controlled study. Results: The significant changes in the blind spots were observed. Electroacupuncture application on the ipsilateral or contralateral ST36 of an enlargement cortical map were associated with the concept of determining the treatment side. In the case of electroacupuncture application on the ipsilateral side of an enlarged blind spot, there were decrease of $4.11{\pm}8.56cm$(17.3%) in blind spot perimetry length(p < 0.05). In the case of contralateral side, there were increase of $3.19{\pm}5.40cm$(13.7%) in blind spot perimetry length(p<0.05). The Differences were statistically significant(p<0.05). Conclusions: We found that eletroacupuncture application was associated with an increase or decrease in the brain function in the view of blind spot changes depending on the treatment side. These results suggest that the traditional acupuncture therapeutic strategy with determining the treatment side has clinical significance in the view of the brain function.

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Monitoring System of Blind Areas in a Skiing Resort using a USN (USN을 이용한 스키장 사각 지역 감시 시스템)

  • Lee, Hyung-Bong;Jung, Ui-Min;Park, Lae-Jeong;Moon, Jung-Ho;Chung, Tae-Yun
    • The KIPS Transactions:PartD
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    • v.16D no.2
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    • pp.249-256
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    • 2009
  • This paper introduces an efficient USN (ubiquitous sensor network) for monitoring blind areas in a skiing resort, developed as a part of u-Sport showcase project of Gangwon Province. Blind areas of a skiing resort are dangerous and/or steep areas located aroud ski slopes, which are rarely traveled and not easily seen by a ski patrol. If an accident occurs in such a blind area, the main control center of the sking resort can hardly recognize the accident and provide first aid and rescue services promptly. The blind area monitoring system proposed in this paper monitors a blind area of a skiing resort using five battery-powered sensor nodes each of which has an image sensor on it and wirelessly transmits images around the blind area to the main control center on a regular basis, therebly allowing real-time monitoring of the blind area and prompt rescue services in case of accidents. Additionally, the monitoring system provides an emergency button which skiers injured in the blind area can push. If the button is pushed, an image around the button and an alarm signal are transmitted to the main control center and therefore the main control center can take prompt actions for rescuing the injured skiers.

A Study on Simulation for Decreasing Energy Demand According to Window-to-Wall Ratio and Installation Blind System in Building (블라인드 도입과 창면적비에 따른 표준건축물의 에너지 수요 저감에 대한 시뮬레이션 연구)

  • Kang, Suk-Min;Lee, Tae-Kyu;Kim, Jeong-Uk
    • Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
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    • v.12 no.6
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    • pp.531-542
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    • 2018
  • Building energy demands have highly risen in modern society; thus, It is necessary to reduce building energy demands especially commercial buildings adopting a curtain wall architecture. Curtain wall architectures have a high ratio of windows which is a vulnerable in heat insulations as cladding. In order to complement insulation performance of windows in these buildings, there are various methods adopted often such as installing blinds, wing wall and films. There are two suggestions of this paper. 1) WWR (Window-to-Wall Ratio) makes a impaction of energy demands in buildings. 2) Another one is an efficiency of blind systems which are installed in buildings in order to reduce cooling demands. It is also critical to make fundamental model for low-energy building construction by processing a lot of simulation As a result by this study, 1) an external blind system is more useful for reducing cooling energy demands rather than an internal blind system. 2) Buildings which have a large window require more amount of cooling demands. In case of WWR 45%, it needs more cooling energy rather than WWR 15% model's 3) Adopting blind system would reduce energy demands. WWR 45% model with external blind systems reduces about 4% of cooling energy demands compared to same model without any blind systems.4) it is necessary to study an efficiency of blind systems combined with renewable energy and it will be possible to reduce more energy demand in building significantly.

Fractionally spaced blind equalization using multi-stage radius-directed algorithm (다단계 반경-지향 알고리듬을 이용한 Fractionally Spaced 블라인드 등화)

  • 이영조;강성진;강창언
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.11
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    • pp.2459-2469
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    • 1997
  • In this paper, the multi-stage radius-directed algorithm is applied to fractionally spaced equalizers which are insensitive to the sampling timing-phase. these equalizers exhibit good convergence characeristics when compared to fractionally spaced blind equalizers using conventional blind algorithms. Also, multi-model fractionally spaced blind equalizers, which use multiple symbol spaced blind equalizers that operate independently, converge faster than conventional fractionally spaced blind equalizers.

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A Study on the Manufacturing Technology of a Folding Blind Rivet (폴딩 블라인드 리벳의 제조기술에 관한 연구)

  • Byun, Hong-Seok;Kim, Young-Ho
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.67-73
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    • 2011
  • In this study, the manufacturing technology of a folding blind rivet was developed through finite element analysis(FEA). Numerical simulations of the folding blind rivet used to join two components have been performed with the finite element method for the forging process design. To minimize the process and manufacture the folding blind rivet without defects, a variety of design rules were proposed. From the results of FEA applied process design rules, an optimal six-stage process was proposed. The finite element simulation results such as shape of the forged rivet, strain distribution and forging load were investigated for the usefulness of the forging process of the blind rivet. In addition, the experiments have been implemented and their results were compared to the analytic results.

Sound Quality Index Development of Electrically Powered Vehicle Roller Blind (차량용 전동 롤러 블라인드의 음질지수 개발)

  • Sung, Weonchan;Jo, Hyeonho;Kim, Seonghyeon;Park, Dongchul;Kang, Yeonjune
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.785-790
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    • 2014
  • The purpose of this study is to identify the significant sound quality metric and compose the sound quality index of motor driven roller blind which is part of vehicle sunroof. Before subjective evaluation, sound characteristics of roller blind was analyzed and set the target operating sound for subjective evaluation. Thus, transfer sound of roller blind which has the characteristics of sound modulation was used for subjective evaluation. Linear regression was carried out by chosen Zwicker's metrics which are pointed by comments of jurors. Loudness and sharpness related metrics are prime metrics in sound quality index we composed. Effect of roller blind assay when it is attached to real vehicle was identified to evaluate the validity of index.

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A Subband Adaptive Blind Equalization Algorithm for FIR MIMO Systems (FIR MIMO 시스템을 위한 부밴드 적응 블라인드 등화 알고리즘)

  • Sohn, Sang-Wook;Lim, Young-Bin;Choi, Hun;Bae, Hyeon-Deok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.2
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    • pp.476-483
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    • 2010
  • If the data are pre-whitened, then gradient adaptive algorithms which are simpler than higher order statistics algorithms can be used in adaptive blind signal estimation. In this paper, we propose a blind subband affine projection algorithm for multiple-input multiple-output adaptive equalization in the blind environments. All of the adaptive filters in subband affine projection equalization are decomposed to polyphase components, and the coefficients of the decomposed adaptive sub-filters are updated by defining the multiple cost functions. An infinite impulse response filter bank is designed for the data pre-whitening. Pre-whitening procedure through subband filtering can speed up the convergence rate of the algorithm without additional computation. Simulation results are presented showing the proposed algorithm's convergence rate, blind equalization and blind signal separation performances.

A Blind Signature Scheme for Customer Anonymity in Contents Purchase (컨텐츠 구입 시 고객의 익명성을 위한 은닉 서명 기법)

  • Lee Hyun-ju;Rhee Chung-Sei
    • Journal of Digital Contents Society
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    • v.5 no.1
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    • pp.1-6
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    • 2004
  • Electronic cash is used as a payment tool for contents purchase in mobile electronic commerce environment. In order to protect customer`s privacy, we use blind signature. Blind signature has an anonymity property since it does not allow connection between customer`s ID and customer`s message. In this paper, we propose an blind signature scheme using elliptic curve algorithm based on Cap Diffie-Hellman Problem. Proposed scheme efficiently improved against existing blind signature scheme by reducing communication and computation time of the process.

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