• Title/Summary/Keyword: air support

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Construction of Environment Management System Based on ubiquitous (유비쿼터스기반의 환경 관제 시스템 구축)

  • Jeong, Chang-Won;Jang, Hyung-Geun;Joo, Su-Chong
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.11
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    • pp.195-204
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    • 2010
  • In this paper, we propose an efficient indoor environment management system which provides the environment management service in ubiquitous computing environment. It is designed to gather data from the user's environment and keep it pleasant with respect to indoor air quality regulation. In order to offer such service Ubiquitous Computing Environment used distributed framework based on the active model for its development and support, while supporting service integration and also we used service oriented architecture. In order to verify the performance of the environment management system, components showed operation while environment management service showed the result through GUI screen.

Fractal Scaling of Permeability in Unsaturated Fractured Tuff: Wavelet-Based Approach

  • Hyun, Yunjung
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.140-143
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    • 2003
  • Air permeabilities in unsaturated fractured tuff at the Apache Leap Research Site (ALRS) near Superior, Arizona, exhibit a self-affine behavior, thus renders a field random fractal. Based up fractal scaling, the observed scale effect has been interpreted [Hyun et al., 2002]. Recently, Frantziskonis and Hansen [2000] presented that fractal scaling can be represented based on wavelets. This study deals with the way of using wavelets for fractal scaling. A numerical study is presented to examine the applicability of wavelet-based approach to determining upscaled air permeability values on various data supports at the site. To characterize the scaling property of self-affine fields generated based upon wavelets, Hurst coefficient, H. was inferred by applying the average wavelet coefficient (AWC) method. The result yielded H = 0.24, which is very close to the result of geostatistical analysis using a power variogram (H = 0.22). The study concludes that wavelet-based scaling is a useful way of determining parameter values on different data supports, which is an essential task for modeling of subsurface flow and mass transport in a numeric grid with different resolutions (grid size).

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The Intermediate Channel Assignment based on Channel Status in High-rate WPAN (HR-WPAN에서 채널 상태에 따른 우회 채널 할당)

  • Lee Jung-Yun;Kim Sung-Su;Kim Jang-Hyung;Song Wang-Cheol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.5
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    • pp.832-842
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    • 2006
  • Wireless Personal Area Networks(WAPANs) are designed for short-range ad hoc connectivity among portable devices. They have gained much attention in the industry recently. One of them, High-rate WPAN, is designed to support multimedia traffic that requires high data rates. But, High-rate WPAN standards don't specify the time slot assignment scheduling method of CAT(Channel Time Allocation). So, there has been many studies regarding time slot assignment scheduling of CAT. However, present studies involve demerits about not applying various types of errors in air interlace or having a starvation of a specific DEV(data device). In this paper, we propose algorithms about supplying the intermediate channel assignment in order to avoid these demerits. This method will help other methods that use time slot assignment scheduling of CTA.

A Study on Indoor Environmental Quality Evaluation in Apartment Buildings - Focus on Apartment Buildings in USA - (공동주택에서의 실내환경의 질 평가에 관한 연구 - 미국 공동주택 사례를 중심으로 -)

  • Yoon, Sung-Hoon
    • Korean Institute of Interior Design Journal
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    • v.18 no.4
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    • pp.79-87
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    • 2009
  • Residential Buildings should provide high-quality, comfortable environments to support the activities of their occupants. The indoor environment of residential buildings, which includes thermal, lighting, acoustic, and indoor air quality, has a significant impact on health and quality of life. The comfortable living environment in residential buildings result from appropriately combining these environmental quality factors, and the performance of building systems must be compatible with the activities of the occupants. The objective of this research is to investigate and analyze the relationship between physical environmental conditions and occupant responses for improving environmental quality (EQ) in apartment buildings with four different building orientations (i.e. E, W, S, N) in two different seasons (i.e. winter and summer). The occupant survey was conducted in actual apartment buildings. The Physical environmental conditions in apartment buildings differed substantially depending on space, outdoor weather conditions and building orientations. Each space within the same apartment building had different environmental conditions. Combinations of unbalanced physical environmental conditions in apartment building decrease occupants' satisfactions and their perceptions of overall residential quality. Occupants' satisfaction and their responses to physical characteristics of their residential environment is related to thermal, lighting, acoustic, and indoor air conditions in their buildings. The result from this research will help designers and researchers to identify problems and develop solutions for improving environmental quality from the occupants' point of view.

Characteristics of Foam Generation in Freshwater and Seawater (담수와 해수에서의 포말 생성 특성)

  • SHIN Jeong-Sik;KIM Byong-Jin;SUH Kuen-Hack
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.3
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    • pp.179-185
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    • 2004
  • The characteristics of foam generation were assessed for freshwater and seawater using a foam generator. Both in freshwater and seawater, the height of the foam layer increased with initial protein concentrations. The height of the foam layer also increased with pore size of the air distributor. The optimum superficial air velocities (SAV) in freshwater and seawater were 0.84 cm/sec and 0.6 cm/sec, respectively. The height of the foam layer was the highest in pH 3 in freshwater and in the region of pH 5-7 in seawater. The height of the foam layer increased with $NaHCO_3$ concentration in freshwater, and $NaHCO_3$ concentration had little effect in seawater. Removal efficiencies of total suspended solid (TSS) and turbidity decreased with an increase of initial protein concentrations in a batch foam separator both in freshwater and seawater.

Design and Performance Evaluation of Attitude Control System for Unfixed Levitation Sculptures (무 고정 공중부양 조형물의 자세 제어장치 설계 및 성능평가)

  • Kang, Jingu
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.13 no.3
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    • pp.11-17
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    • 2017
  • The aerial support air sculptures currently exhibited in indoor spaces are similar to simple ad balloons, using multiple rope strands. Users now want more advanced unfixed sculptures, and hope these will develop into buoyant sculptures that can maintain the attitudes that users want on their own. This study investigated an attitude control system for unfixed levitation sculptures that can levitate with no rope and continuously maintain a certain attitude at a height specified by the user. To facilitate levitation, the exterior part of the sculpture was made of lightweight fibers, and the interior part was filled with helium gas. The controller was composed of a microprocessor of the dsPIC30F line from microchip, gyro, acceleration, and earth magnetic field sensors, and a highly efficient brushless DC (BLDC) electric motor. The attitude and position control system requires scheduling considering the trajectories of the sculpture and the control system, because the roles of the overall components are more important than those of a single controller. Furthermore, the system was designed like a fusion system that is expanded and controlled as a total controller, because it is interconnected with various sensors. The attitude control system of buoyant sculptures was implemented in this study, such that it can actively cope with the position, direction, stopping, and time aspects. The system performance was then evaluated.

Changes in Waterproofness and Breathability after Repeated Laundering and Durability of Electrospun Nanofiber Web Laminates (전기방사한 나노섬유 웹 라미네이트 소재의 반복 세탁에 따른 투습방수 성능 변화 및 내구성)

  • Lee, Kyung;Yoon, Bo-Ram;Lee, Seung-Sin
    • Fashion & Textile Research Journal
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    • v.14 no.1
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    • pp.122-129
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    • 2012
  • To develop a waterproof breathable material, we fabricated three kinds of nanofiber web laminates using a massproduced electrospun nanofiber web with different substrates and layer structures. The waterproofness and breathability of nanofiber web laminates were evaluated after repeated launderings and compared with those of conventional waterproof breathable fabrics currently in use, including densely woven fabric, microporous membrane laminated fabric, and coated fabric. The durability of nanofiber web laminates, including adhesion strength, abrasion resistance, tensile strength, and tearing strength, was also assessed and compared with those of conventional waterproof breathable fabrics. The water vapor transmission of nanofiber web laminates increased slightly after repeated launderings, whereas the air permeability somewhat decreased after launderings but still maintained an acceptable level of air permeability. Laundering reduced the resistance to water penetration of nanofiber web laminates, which implies that laminating techniques or substrate materials that could support waterproofness of the laminated structure should be explored. The adhesion strength, abrasion resistance, tensile strength, and tearing strength of nanofiber web laminates were in a range comparable to conventional waterproof breathable materials.

What are the Determinants to form of Air Logistics Cluster and what are their Effects (Focus on Incheon International Airport) (인천국제공항의 물류클러스터 결정요인 및 효과에 관한 연구)

  • Park, Seon-Gyeong;Hong, Seok-Jin;Kim, Cheon-Su
    • Journal of Korean Society of Transportation
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    • v.29 no.1
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    • pp.7-15
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    • 2011
  • Recently, airport competitiveness measure is not only passenger and cargo throughput but also value-added activities of their hinterland and airport city. That is, airport competitiveness comes from airport versus airport to airport with their own-supplied city and hinterland connected with airport to provide diversified functions. This study surveyed and analyzed how to form a cluster focused on Incheon International Airport and what are important factors to form of cluster in achieving competences. These clusters need government's political support. In this case, there was a shortage of specialized human resources in competent local suppliers, and limited informations sharing.

Comparative Study on the Protective Functions of Clothes (의복의 보호론에 관한 이론적 고찰)

  • Lim Sook Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.9 no.3
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    • pp.71-78
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    • 1985
  • This research is designed to systemize the protection theory as well as to supplement the missing theory by organizing various studies on the protective functions of celothes by domestic and foreign scholers of clothing. Human environments is classified two standpoints : (1) Physical environments, and (2) man built psychological environments including socio-physical environments, socio-biological environments, behavioral environments, socio-psychological environments and institution environments. Clothes acting as a physical protection might be of (1) extreme air temperature: Parka; (2) high relative humidity: raincoat; (3) air movement: windbreaker; (4) radiation: space suit; (5) atmospheric pressure: deep sea diver suit; (6) mechanical agent: bullet proof vest; (7) physical agent: (8) chemical agent: (9) biological agent: surgeon's gown, cap, and mask. Also dresses act to support the body comfort, health and the well-being; corset for bad back patient, wrist band for people with weak wrist, bottom half of pressure suit for people with low blood pressure. Clothes acting as a psychological protection might be of (1) influence of magic and of spirits: (2) moral danger; (3) the general unfriendliness of the world as a whole; a reassurance against the lack of love. Clothes should provide the maximum of satisfaction in accordance with the full recognition of reality. The reality should aim at the formulation of general laws concerning the most pleasing forms, colors, and styles to suit. The complex physiological anatomical and psychological aspects of individual personalities.

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Performance Test of Scroll Expander for Micro-Power Generation (소규모 발전용 스크롤 팽창기 성능시험)

  • Kim Hyun J.;Park Ik S.;Rha Phil C.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.4
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    • pp.325-332
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    • 2005
  • This paper addresses the development of a scroll expander for power generation from relatively low temperature steam source. It has a double-sided orbiting scroll member so that no thrust bearing is needed to support the base plate of the orbiting scroll. Three power transmission shafts are placed at the periphery of the orbiting scroll base plate, and these shafts can also function as anti-rotation devices. Final output is obtained from the main central shaft engaged with the three power transmission shafts through gear assembly. The clearance between the fixed and orbiting scroll elements was estimated by comparing measurement of the mass flow rate with calculation results of a computer simulation. Due to large clearance, the expander total and volumetric efficiencies were measured to be $34\%\;and\;43\%$, respectively. It has been shown through the computer simulation that the total and volumetric efficiencies could be improved to $65\%\;and\;83\%$, respectively, if the current clearance is reduced by half.