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The Kinematics Analysis of the Badminton High Clear Motion in Woman Middle School Student (여자중학생 배드민턴 하이클리어 동작의 운동학적 분석)

  • Kim, Chang-Bum;Ryu, Jae-Kwang
    • Korean Journal of Applied Biomechanics
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    • v.12 no.2
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    • pp.91-107
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    • 2002
  • This research got the following conclusion as result that analyzed high clear action kinematically to 4 C girls' junior high school badminton players who are situated in Chungchong-bukdo. 1. Most of the subject didn't rotate their right shoulder and elbow joint at back swing and moved speedy to shuttle cock. And an cooperation action of joint decreases displaying only a good action on both subject`s specification joint part. 2. When the subject S1 and S2 swing slowly and largely the joint of shoulder and elbow and then the speed of right wrist and racket head is fast, the cooperation action of joint is better than other subject. 3. An angle change of right shoulder showed angle that all subjects are great being caused in softness of joint and angular velocity was exposed that load enough Impact force and increase the speed of racket head as angular velocity decreases rapidly in Impact except subject S3. 4. All subjects of right elbow angle change showed similar form and was exposed that subject S2 sees form of impact stage serious bends from back swing and do not use force effectively in angular velocity. 5. Angle of right wrist appeared that the speed of shuttle cock is decelerated because fast bends of wrist is not formed shortly after Impact because all subject do not accomplish big angle shortly after back swing. Angular velocity can assume that the subject S1 and S4 are using and move fast strong snap shot offering angular velocity value of Impact stage sound (-). 6. While size of Impact stage knee angle accomplishes angle that is big both subject, hip joint angles sees small angle and is playing swing that do on upper body and arm without using strong waist force that is composition action with knee and hip joint.

Reliability Based Stability Analysis and Design Criteria for Reinforced Concrete Retaining Wall (신뢰성(信賴性) 이론(理論)에 의한 R.C.옹벽(擁壁)의 안정해석(安定解析) 및 설계규준(設計規準))

  • Cho, Tae Song;Cho, Hyo Nam;Chun, Chai Myung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.3 no.3
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    • pp.71-86
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    • 1983
  • Current R.C. retaining wall design is bared on WSD, but the reliability based design method is more rational than the WSD. For this reason, this study proposes a reliability based design criteria for the cantilever retaining wall, which is most common type of retaining wall, and also proposes the theoretical bases of nominal safety factors of stability analysis by introducing the reliability theory. The limit state equations of stability analysis and design of each part of cantilever retaining wall are derived and the uncertainty measuring algorithms of each equation are also derived by MFOSM using Coulomb's coefficient of the active earth pressure and Hansen's bearing capacity formula. The levels of uncertainties corresponding to these algorithms are proposed appropriate values considering our actuality. The target reliability indices (overturning: ${\beta}_0$=4.0, sliding: ${\beta}_0$=3.5, bearing capacity: [${\beta}_0$=3.0, design for flexure: [${\beta}_0$=3.0, design for shear: ${\beta}_0$=3.2) are selected as optimal values considering our practice based on the calibration with the current R.C. retaining wall design safety provisions. Load and resistance factors are measured by using the proposed uncertainties and the selected target reliability indices. Furthermore, a set of nominal safety factors, allowable stresses, and allowable shear stresses are proposed for the current WSD design provisions. It may be asserted that the proposed LRFD reliability based design criteria for the R.C. retaining wall may have to be incorporated into the current R.C. design codes as a design provision corresponding to the USD provisions of the current R.C. design code.

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Application of geophysical exploration methods for safety diagnosis of the basement of stone pagoda (지구물리탐사 방법의 석탑지반 안전진단에의 적용)

  • Suh, Man-Cheol;Oh, Jin-Yong;Kim, Ki-Hyun
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.08a
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    • pp.70-83
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    • 2004
  • The safety diagnosis of cultural assets is Primarily focused on its non-destructiveness. Research on the nondestructive diagnosis and conservation of masonry cultural heritage is the key which is considered by technologic kernel. Geophyscial Prospecting as nondestructive diagnostic technology plays an important role in the characterization of the foundation of stone pagodas. It is natural that understanding of shallow subsurface condition beneath them is essential for their structural safety diagnosis. As an example, the nondestructive geophysical methods were applied to two three-story stone pagodas, Seokgatap (height 10.8 m, width 4.4 m, weight 82.3 ton) and Dabotap (height 10.4 m, width 7.4 m, weight 123.2 ton) which were built in 791 at Bulkuksa temple. An earlier archaeological investigation shows that stone pagodas have experienced severe weathering process and are slightly leaning, which will threaten their stability At the base part of Dabotap, an offset of the stone alignment is also observed. Direct measurements of ultrasonic velocities was introduced for the mechanical properties of the stone The velocity ranges of ultrasonic waves for Dabotap and Seokgatap are 1217${\~}$4403 m/s and 584${\~}$5845 m/s, respectively, and the estimated averages of the uniaxial compressive strength are 463 kg/$cm^2$ and 409 kg/$cm^2$, respectively. Site characteristics, around the pagodas are determined by the measurement of multiple properties such as seismic velocity, resistivity, image of ground-penetrating radar, On the basis of the higher velocity structure, the site of Seokgatap appears to have solider stability than the Seokgatap site. Near the pagodas, higher(up to 2200 $\Omega$m) resistivity is present whereas their outskirts have as low as 200 $\Omega$m. By the combined results of each geophyscial methods, the subsurface boundaries of two stone pagodas are revealed. The Dabotap site is in the form of an octagon having 6-m-long side with the depth of ${\~}$4 m, whereas the Seokgatap site is the 8 ${\times}$ 10 m rectangle with the depth of 3 m. These subsurface structures appear to reflect the original foundations constructed against the stone load of ${\~}8 ton/m^2$. At the subsurface beneath the northeast of each pagoda, low seismic velocity as well as low resistivity is prominent. It is interpreted to represent the weak underground condition which Is the possible cause of the slightly leaning pagodas toward the NNW.

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A Review on Ultimate Lateral Capacity Prediction of Rigid Drilled Shafts Installed in Sand (사질토에 설치된 강성현장타설말뚝의 극한수평지지력 예측에 관한 재고)

  • Cho Nam Jun;Kulhawy F.H
    • Journal of the Korean Geotechnical Society
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    • v.21 no.2
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    • pp.113-120
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    • 2005
  • An understanding of soil-structure interaction is the key to rational and economical design for laterally loaded drilled shafts. It is very difficult to formulate the ultimate lateral capacity into a general equation because of the inherent soil nonlincarity, nonhomogeneity, and complexity enhanced by the three dimensional and asymmetric nature of the problem though extensive research works on the behavior of deep foundations subjected to lateral loads have been conducted for several decades. This study reviews the four most well known methods (i.e., Reese, Broms, Hansen, and Davidson) among many design methods according to the specific site conditions, the drilled shaft geometric characteristics (D/B ratios), and the loading conditions. And the hyperbolic lateral capacities (H$_h$) interpreted by the hyperbolic transformation of the load-displacement curves obtained from model tests carried out as a part of this research have been compared with the ultimate lateral capacities (Hu) predicted by the four methods. The H$_u$ / H$_h$ ratios from Reese's and Hansen's methods are 0.966 and 1.015, respectively, which shows both the two methods yield results very close to the test results. Whereas the H$_u$ predicted by Davidson's method is larger than H$_h$ by about $30\%$, the C.0.V. of the predicted lateral capacities by Davidson is the smallest among the four. Broms' method, the simplest among the few methods, gives H$_u$ / H$_h$ : 0.896, which estimates the ultimate lateral capacity smaller than the others because some other resisting sources against lateral loading are neglected in this method. But it results in one of the most reliable methods with the smallest S.D. in predicting the ultimate lateral capacity. Conclusively, none of the four can be superior to the others in a sense of the accuracy of predicting the ultimate lateral capacity. Also, regardless of how sophisticated or complicated the calculating procedures are, the reliability in the lateral capacity predictions seems to be a different issue.

Experimental study on the relaxation zone depending on the width and distance of the weak zone existing ahead of tunnel face (터널 굴진면 전방에 위치한 연약대 폭과 이격거리에 따른 이완영역에 대한 실험적 연구)

  • Ham, Hyeon Su;Lee, Sang Duk
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.5
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    • pp.855-867
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    • 2018
  • When a weak zone exists ahead of tunnel face, the stress in the adjacent area would increase due to the longitudinal arching effect and the stability of the tunnel is affected. Therefore, it is critical to prepare a countermeasure through the investigation of the frontal weakness zone of the excavated face. Although there are several researches to predict the existence of weak zone ahead of tunnel face, such as geophysical exploration, numerical analysis and tunnel support, lack of studies on the relaxation zone depending on the width or distance from the vulnerable area. In this study, the impact of the weak zone on the formation of the relaxation zone was investigated. For this purpose, a series of laboratory test were carried out varying the width of the weak zone and the separation distance between tunnel face and weak zone. In the model test, sand with a water content of 3.8% was used to form a model ground. The model weak zone was constructed with dry sand curtains. The tunnel face was adjusted to allow a sequential excavation of upper and lower half part. load cells were installed on the bottom of the foundation and the tunnel face and measuring instruments for displacement were installed on the surface of the model ground to measure the vertical stress and surface displacements due to tunnel excavation respectively. The test results show that the width of weak zone did not affect the ground settlement while the ground subsidence drastically increased within 0.25D. The vertical stress and horizontal stress increased from 0.5D or less. In addition, the longitudinal arching effect is likely within the 1.0D zone ahead of the tunnel face, which may reduce the vertical stress in the ground following tunneling direction.

Limitations on Exclusive Rights of Authors for Library Reprography : A Comparative Examination of the Draft Revision of Korean Copyright Law with the New American Copyright Act of 1976 (저작권법에 준한 도서관봉사에 관한 연구 -미국과 한국의 저자재산권의 제한규정을 중시으로-)

  • 김향신
    • Journal of Korean Library and Information Science Society
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    • v.11
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    • pp.69-99
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    • 1984
  • A dramatic development in the new technology of copying materials has presented us with massive problems on reconciling the conflicts between copyright owners and potential users of copyrighted materials. The adaptation to this changing condition led some countries to revise their copyright laws such as in the U. S. in 1976 and in Korea in 1984 for merging with the international or universal copyright conventions in the future. Copyright defined as exclusive rights given to copyright owners aims to secure a fair return for an author's creative labor and to stimulate artistic creativity for the general public good. The exclusive rights on copyrightable matters, generally for reproduction, preparation of derivative works, public distribution, public performance, and public display, are limited by fair use for scholarship and criticism and by library reproduction for its preservation and interlibrary loan. These limitations on the exclusive rights are concerned with all aspects of library services and cause a great burden on librarian's daily duty to provide balance between the rights of creators and the needs of library patrons. The fair use as one of the limitations on it has been coupled with enormous growth of a new technology and extended from xerography to online database systems. The implementation of the fair use and library reprography in Korean law to the local practices is examined on the basis of the new American copyright act of 1976. Under the draft revision of Korean law, librarians will face many potential problems as summarized below. 1. Because the new provision of 'life time plus 50 years' will tie up substantial bodies of material longer than the old law, until that date librarians would need permissions from the owners and should pay attention to the author's death date. 2. Because the copyright can be sold, distributed, given to the heirs, donated, as a whole or a part, librarians should chase down the heirs and other second owners. In case of a derivative work, this is a real problem. 3. Since a work has its protection from the moment of its creation, the coverage of copyrightable matter would be extended to the published or the unpublished works and librarian's work load would be heavier. Without copyright registration, no one can be certain that a work is in the public domain. Therefore, librarians will need to check with an authority. 4. For implementation of limitations on exclusive rights, fair use and library reproduction for interlibrary loan, there can be no substantial aggregate use and there can be no systematic distribution of multicopies. Therefore, librarians should not substitute reproductions for subscriptions or purchases. 5. For the interlibrary loan by photocopying, librarians should understand the procedure of royalty payment. 6. Compulsory licenses should be understood by librarians. 7. Because the draft revision of Korean law is a reciprocal treaty, librarians should take care of other countries' copyright law to protect foreign authors from Korean law. In order to solve the above problems, some suggestions are presented below. 1. That copyright clearinghouse or central agency as a centralized royalty payment mechanism be established. 2. That the Korean Library Association establish a committee on copyright. 3. That the Korean Library Association propose guidelines for each occasion, e.g. for interlibrary loan, books and periodicals and music, etc. 4. That the Korean government establish a copyright office or an official organization for copyright control other than the copyright committee already organized by the government. 5. That the Korean Library Association establish educational programs on copyright for librarians through seminars or articles written in its magazines. 6. That individual libraries provide librarian's copyright kits. 7. That school libraries distribute subject bibliographies on copyright law to teachers. However, librarians should keep in mind that limitations on exclusive rights are not for an exemption from library reprography but as a convenient access to library resources.

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Location Service Modeling of Distributed GIS for Replication Geospatial Information Object Management (중복 지리정보 객체 관리를 위한 분산 지리정보 시스템의 위치 서비스 모델링)

  • Jeong, Chang-Won;Lee, Won-Jung;Lee, Jae-Wan;Joo, Su-Chong
    • The KIPS Transactions:PartD
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    • v.13D no.7 s.110
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    • pp.985-996
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    • 2006
  • As the internet technologies develop, the geographic information system environment is changing to the web-based service. Since geospatial information of the existing Web-GIS services were developed independently, there is no interoperability to support diverse map formats. In spite of the same geospatial information object it can be used for various proposes that is duplicated in GIS separately. It needs intelligent strategies for optimal replica selection, which is identification of replication geospatial information objects. And for management of replication objects, OMG, GLOBE and GRID computing suggested related frameworks. But these researches are not thorough going enough in case of geospatial information object. This paper presents a model of location service, which is supported for optimal selection among replication and management of replication objects. It is consist of tree main services. The first is binding service which can save names and properties of object defined by users according to service offers and enable clients to search them on the service of offers. The second is location service which can manage location information with contact records. And obtains performance information by the Load Sharing Facility on system independently with contact address. The third is intelligent selection service which can obtain basic/performance information from the binding service/location service and provide both faster access and better performance characteristics by rules as intelligent model based on rough sets. For the validity of location service model, this research presents the processes of location service execution with Graphic User Interface.

Changes of Heart Rate During Marathon Running (장거리 (마라톤)선수에서의 전 경기중 심박동수의 변화)

  • Kim, In-Kyo;Lee, Jung-Woo;Hah, Jong-Sik;Ryu, Yun-Hee;Choi, Jung-Ok;Kim, Ki-Ho
    • The Korean Journal of Physiology
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    • v.13 no.1_2
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    • pp.1-12
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    • 1979
  • To evaluate the present status of physical fittness of Korean long distance runners, body fat, pulmonary functions, maximal oxygen intake and oxygen debt were measured in 5 elite marathoners (A group), 6 college student runners (B group) and 3 middle school student runners (C group). After laboratory tests, full course marathon running was performed in 2 elite marathoners during which their heart rates were monitored continuously. The results are summerized as follows: 1) Total body fat in all three groups are in the range of 13-15% of their body weight. 2) In all three groups, average values of various pulmonary functions were within the normal limits, but those of tidal volume were higher and respiratory rate were lower in comparison to normal values. These phenomena may represent respiratory adaptations against training. The average resting oxygen consumptions in A,B and C were $322{\pm}23$, $278{\pm}14$ and $287{\pm}16$m1/min, respectively. 3) In all three groups, resting blood pressures were in the normal range, but the resting heart rate was slightly lower in groups A $(56{\pm}3\;beats/min)$ and B $(64{\pm}2\;beats/min)$ and higher in group C $(82{\pm}9\;beats/min)$ in comparison to normal values. These changes in cardiovascular functions in marathoners may also represent adaptive phenomena. 4) During treadmill running the minute ventilation and oxygen consumption of the runners increased lineally with work load in all three groups. When the oxygen consumption was related to heart rate, it appeared to be a exponential function of the heart rate in all three groups. 5) The average maximal heart rates during maximal work were $196{\pm}3$, $191{\pm}3$ and $196{\pm}5\;beats/min$ for groups A,B and C, respectively. Maximal oxygen intakes were $84.2{\pm}3.3\;ml/min/kg$ in group A, $65.2{\pm}1.1\;ml/min/kg$ in group B and $58.7{\pm}0.4\;ml/min/kg$ in group C. 6) In all three groups, oxygen debts and the rates of recovery of heart rate after treadmill running were lower than those of long ditsance runners reported previously. 7) The 40 km running time in 2 elite marathoners was recorded to be $2^{\circ}42'25'$, and their mean speed was 243 m/min (ranged 218 to 274 m/min). The heart rate appeared to increase lineally with running speed, and the total energy expenditure during 40 km running was approximately 1360.2 Calories. From these it can be speculated that if their heart rates were maintained at 166 beats/min during the full course of marathon running, their records would be arround $2^{\circ}15'$. Based on these results, we may suspect that a successful long distance running is, in part, dependent on the economical utilization of one's aerobic capacity.

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Study on Climate Change Impacts on Hydrological Response using a SWAT model in the Xe Bang Fai River Basin, Lao People's Democratic Republic (기후변화에 따른 라오스인민공화국의 시방파이 유역의 수문현상 예측에 대한 연구: SWAT 모델을 이용하여)

  • Phomsouvanh, Virasith;Phetpaseuth, Vannaphone;Park, Soo Jin
    • Journal of the Korean Geographical Society
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    • v.51 no.6
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    • pp.779-797
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    • 2016
  • A calibrated hydrological model is a useful tool for quantifying the impacts of the climate variations and land use/land cover changes on sediment load, water quality and runoff. In the rainy season each year, the Xe Bang Fai river basin is provisionally flooded because of typhoons, the frequency and intensity of which are sensitive to ongoing climate change. Severe heavy rainfall has continuously occurred in this basin area, often causing severe floods at downstream of the Xe Bang Fai river basin. The main purpose of this study is to investigate the climate change impact on river discharge using a Soil and Water Assessment Tool (SWAT) model based on future climate change scenarios. In this study, the simulation of hydrological river discharge is used by SWAT model, covering a total area of $10,064km^2$ in the central part of country. The hydrological model (baseline) is calibrated and validated for two periods: 2001-2005 and 2006-2010, respectively. The monthly simulation outcomes during the calibration and validation model are good results with $R^2$ > 0.9 and ENS > 0.9. Because of ongoing climate change, three climate models (IPSL CM5A-MR 2030, GISS E2-R-CC 2030 and GFDL CM3 2030) indicate that the rainfall in this area is likely to increase up to 10% during the summer monsoon season in the near future, year 2030. As a result of these precipitation increases, the SWAT model predicts rainy season (Jul-Aug-Sep) river discharge at the Xebangfai@bridge station will be about $800m^3/s$ larger than the present. This calibrated model is expected to contribute for preventing flood disaster risk and sustainable development of Laos

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Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 (설비공학 분야의 최근 연구 동향: 2014년 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.27 no.7
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. 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 heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were newly added in thermal and fluid engineering research area. (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 for thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen 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, and renewable energies, piping in the buildings. Proposed designs, performance performance tests using numerical methods and experiments provide useful information and key data which can improve 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 evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.