• Nuclear Engineering and Technology
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• 제56권3호
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• pp.803-811
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• 2024

Nuclear accidents such as Fukushima Daiichi have highlighted the potential of passive safety systems to replace or complement active safety systems as part of the overall prevention and/or mitigation strategies. In addition, passive systems are key features of Small Modular Reactors (SMRs), for which they are becoming almost unavoidable and are part of the basic design of many reactors available in today's nuclear market. Nevertheless, their potential to significantly increase the safety of nuclear power plants still needs to be strengthened, in particular the ability of computer codes to determine their performance and reliability in industrial applications and support the safety demonstration. The PASTELS project (September 2020-February 2024), funded by the European Commission "Euratom H2020" programme, is devoted to the study of passive systems relying on natural circulation. The project focuses on two types, namely the SAfety COndenser (SACO) for the evacuation of the core residual power and the Containment Wall Condenser (CWC) for the reduction of heat and pressure in the containment vessel in case of accident. A specific design for each of these systems is being investigated in the project. Firstly, a straight vertical pool type of SACO has been implemented on the Framatome's PKL loop at Erlangen. It represents a tube bundle type heat exchanger that transfers heat from the secondary circuit to the water pool in which it is immersed by condensing the vapour generated in the steam generator. Secondly, the project relies on the CWC installed on the PASI test loop at LUT University in Finland. This facility reproduces the thermal-hydraulic behaviour of a Passive Containment Cooling System (PCCS) mainly composed of a CWC, a heat exchanger in the containment vessel connected to a water tank at atmospheric pressure outside the vessel which represents the ultimate heat sink. Several activities are carried out within the framework of the project. Different tests are conducted on these integral test facilities to produce new and relevant experimental data allowing to better characterize the physical behaviours and the performances of these systems for various thermo-hydraulic conditions. These test programmes are simulated by different codes acting at different scales, mainly system and CFD codes. New "system/CFD" coupling approaches are also considered to evaluate their potential to benefit both from the accuracy of CFD in regions where local 3D effects are dominant and system codes whose computational speed, robustness and general level of physical validation are particularly appreciated in industrial studies. In parallel, the project includes the study of single and two-phase natural circulation loops through a bibliographical study and the simulations of the PERSEO and HERO-2 experimental facilities. After a synthetic presentation of the project and its objectives, this article provides the reader with findings related to the physical analysis of the test results obtained on the PKL and PASI installations as well an overall evaluation of the capability of the different numerical tools to simulate passive systems.

• Structural Engineering and Mechanics
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• 제90권6호
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• pp.611-633
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• 2024

This study intends to investigate the response of multi-cell (MC) beams to flexural loads in which the primary reinforcement is composed of both metallic and non-metallic materials. "Multi-cell" describes beam sections with multiple longitudinal voids separated by thin webs. Seven reinforced concrete MC beams measuring 300×200×1800 mm were tested under flexural loadings until failure. Two series of beams are formed, depending on the type of main reinforcement that is being used. A control RC beam with no openings and six MC beams are found in these two series. Series one and two are reinforced with metallic and non-metallic main reinforcement, respectively, in order to maintain a constant reinforcement ratio. The first crack, ultimate load, deflection, ductility index, energy absorption, strain characteristics, crack pattern, and failure mode were among the structural parameters of the beams under investigation that were documented. The primary variables that vary are the kind of reinforcing materials that are utilized, as well as the kind and quantity of mesh layers. The outcomes of this study that looked at the experimental and numerical performance of ferrocement reinforced concrete MC beams are presented in this article. Nonlinear finite element analysis (NLFEA) was performed with ANSYS-16.0 software to demonstrate the behavior of composite MC beams with holes. A parametric study is also carried out to investigate the factors, such as opening size, that can most strongly affect the mechanical behavior of the suggested model. The experimental and numerical results obtained demonstrate that the FE simulations generated an acceptable degree of experimental value estimation. It's also important to demonstrate that, when compared to the control beam, the MC beam reinforced with geogrid mesh (MCGB) decreases its strength capacity by a maximum of 73.33%. In contrast, the minimum strength reduction value of 16.71% is observed in the MC beams reinforced with carbon reinforcing bars (MCCR). The findings of the experiments on MC beams with openings demonstrate that the presence of openings has a significant impact on the behavior of the beams, as there is a decrease in both the ultimate load and maximum deflection.

• Korean Journal of Radiology
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• 제21권7호
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• 대한영상의학회지
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• 제84권1호
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• pp.150-169
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• 2023

다발성 골수종은 골수에서 클론 형질 세포의 증식으로 인한 악성 혈액 질환으로 최근 우리나라에서도 발병률이 증가하고 있다. 다발성 골수종의 치료법이 발전하면서 질환의 조기 진단과 조기 치료의 필요성이 대두되었고 International Myeloma Working Group (이하 IMWG) 중심으로 질병의 진단의학적, 영상의학적 진단 기준이 여러 차례 개정되고 있다. 또한 다발성 골수종 환자의 진단과 치료 반응 평가에 전신 자기공명영상(whole body MR; 이하 WBMR)의 사용량이 증가하면서 WBMR의 영상 획득 기법이나 영상 결과 해석, 반응평가법을 표준화하기 위해 Myeloma Response Assessment and Diagnosis System (이하 MYRADS)가 만들어졌다. 이 종설에서는 다발성 골수종의 정확한 진단을 위해 영상의학과 의사로서 알아야 할 최신 지견으로 IMWG의 최신 가이드라인에 따른 다발성 골수종의 영상검사법 및 MY-RADS에 따른 WBMR에서의 영상 획득 기법 및 반응 평가 기법에 대해 설명하였다.

• 생명과학회지
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• 제28권9호
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• pp.1056-1061
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• 2018

본 연구에서는 해양 한천분해세균 Agarivorans sp. KC-1과 해당균주의 agarase 특성을 조사하였다. 한천분해균인 KC-1은 경상남도 사천시 남일대 해수욕장에서 채취한 바닷물을 이용하여 Marine broth 2216 한천 배지에서 분리하였다. 분리된 균은 16S rRNA 유전자 염기서열분석을 통하여 Agarivorans 속 세균과 99% 일치하여 Agarivorans sp. KC-1으로 명명하였다. 세포외로 분비되는 agarase는 Agarivorans sp. KC-1 균주 배양액에서 획득하였으며, 이를 이용하여 특성 조사를 하였다. Agarivorans sp. KC-1 균주의 한천분해효소는 20, 30, 40, 50, 60 및 $70^{\circ}C$에서 각각 65, 91, 96, 100, 77, 35%의 상대활성을 나타냈으며, pH 5, 6, 7, 8에서는 93, 100, 87, 82%의 활성을 나타내었다. 세포외 agarase는 $50^{\circ}C$에서 pH 6.0인 20 mM Tris-HCl 완충용액을 사용하였을 때 최대(254 U/l)의 활성을 보였다. 이 agarase는 20, 30, $40^{\circ}C$에서 2시간 동안 열처리 하여도 90% 이상의 잔존활성을 보였다. 또한, $50^{\circ}C$에 2시간 노출된 후에도 67%의 잔존활성을 보였다. Zymogram 분석을 통하여 Agarivorans sp. KC-1 균주가 생산하는 한천분해효소의 크기는 약 130 kDa, 80 kDa, 69 kDa의 3개로 확인할 수 있었다. TLC 분석 결과, Agarivorans sp. KC-1 균주의 한천분해효소는 네오한천올리고당인 neoagarohexaose (21.6%), neoagarotetraose (32.2%) 및 neoagarobiose (46.2%)를 생성하는 것으로 보아 ${\beta}$-agarase로 확인되었다. 따라서 Agarivorans sp. KC-1가 생산하는 ${\beta}$-agarase는 전분노화 방지, 미백효과, 보습효과 및 세균생장 억제 등의 기능을 가지는 한천올리고당의 생산에 유용할 것으로 판단된다.

• 유통과학연구
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• 제15권5호
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• pp.49-52
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• 2017

Purpose - To improve and strengthen existing publication and research ethics, KODISA has identified and presented various cases which have violated publication and research ethics and principles in recent years. The editorial office of KODISA has been providing and continues to provide advice and feedback on publication ethics to researchers during peer review and editorial decision making process. Providing advice and feedback on publication ethics will ensure researchers to have an opportunity to correct their mistakes or make appropriate decisions and avoid any violations in research ethics. The purpose of this paper is to identify different cases of ethical violation in research and inform and educate researchers to avoid any violations in publication and research ethics. Furthermore, this article will demonstrate how KODISA journals identify and penalize ethical violations and strengthens its publication ethics and practices. Research design, data and methodology - This paper examines different types of ethical violation in publication and research ethics. The paper identifies and analyzes all ethical violations in research and combines them into five general categories. Those five general types of ethical violations are thoroughly examined and discussed. Results - Ethical violations of research occur in various forms at regular intervals; in other words, unethical researchers tend to commit different types of ethical violations repeatedly at same time. The five categories of ethical violation in research are as follows: (1) Arbitrary changes or additions in author(s) happen frequently in thesis/dissertation related publications. (2) Self plagiarism, submitting same work or mixture of previous works with or without using proper citations, also occurs frequently, but the most common type of plagiarism is changing the statistical results and using them to present as the results of the empirical analysis; (3) Translation plagiarism, another ethical violation in publication, is difficult to detect but occurs frequently; (4) Fabrication of data or statistical analysis also occurs frequently. KODISA requires authors to submit the results of the empirical analysis of the paper (the output of the statistical program) to prevent this type of ethical violation; (5) Mashup or aggregator plagiarism, submitting a mix of several different works with or without proper citations without alterations, is very difficult to detect, and KODISA journals consider this type of plagiarism as the worst ethical violation. Conclusions - There are some individual cases of ethical violation in research and publication that could not be included in the five categories presented throughout the paper. KODISA and its editorial office should continue to develop, revise, and strengthen their publication ethics, to learn and share different ways to detect any ethical violations in research and publication, to train and educate its editorial members and researchers, and to analyze and share different cases of ethical violations with the scholarly community.

• 환경정책연구
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• 제8권2호
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• pp.83-118
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• 2009

교토의 정서에 따른 청정개발체제(Clean Development Mechanism, CDM) 사업은 두 가지 목적을 가지고 있다. 하나는 온실가스 감축의무가 있는 나라가 다른 나라에서 온실가스 감축사업을 하여 생긴 감축량으로 자국의 감축의무 이행에 사용할 수 있게 허용하여 비용효과적인 감축의무 이행을 도와주는 것이고 다른 하나는 개발도상국에 대한 투자를 통해 개도국에 기술 이전과 지속가능한 발전을 도모하는 것이다. 그러나 CDM 사업의 현실을 보면 전자의 목적은 달성하고 있으나 후자의 목적은 별로 충족하지 못하고 있다는 지적이 많다. 본 연구는 이러한 상황을 반영하여 우리나라에 맞는 지속가능성 평가 기준을 제시하고자 시도하였다. 여러 가지 의사결정 방법론을 비교하여 다기준분석법(MCA)의 하나인 다속성효용이론(MAUT)을 이용하는 것이 가장 유용하다는 판단에 따라 그에 적절한 요건을 갖는 지속가능성 기준을 파악하고자 하였다. 국내에서는 초기단계에 있는 연구이기 때문에, 국내 전문가의 의견만으로는 보편적 국제적 기준을 놓칠 우려가 있어 외국의 사례에 대한 광범위한 조사를 하였다. 국내 전문가들에게는 GRI가 제시한 기준과 국내외 사례에서 뽑은 37개의 예비 기준을 제시하여 지표의 적합성(relevance), 개선 가능성(possibility of real improvement), 자료수집의 용이성(easiness of data collection), 주관적 선호도(preferences) 등 네 가지 측면에서 1-3점을 각각 부여하도록 설문하였다. 분석 결과는 외국의 11개 사례에서 나온 상위 15개 기준과 국내 설문 결과 상위 15위 기준을 취합하여 12개의 핵심 기준과 10개의 부가 기준을 제시할 수 있었다. 이후 이를 구체적 사업에 적용하여 사례 분석을 시도하였다. 평가 대상 사업으로는 세계 최대의 조력발전 CDM 사업인 "시화호 발전사업"을 선정하고 핵심 지표 12개에 의미있다고 판단되는 3개의 부가지표를 더해 총 15개의 적용지표를 선정한 후, 각 지표별 가중치 설정을 위하여 경제, 환경 사회 각 부문의 전문가에게 두 기준 간의 상대적 선호도를 묻는 AHP 설문을 수행하였다. 이를 Expert Choice라는 전문 소프트웨어를 이용하여 분석하였다. 일관성이 확인된 14명의 응답을 기준으로 종합 점수를 계산한 결과 (+)53.082의 점수가 확인되었고 다양한 경우에 대한 민감도 분석의 결과도 모두 (+)44.667과 (+)65.522 사이에 분포하여 지속가능한 발전에 기여하는 순편익이 더 높은 것으로 확인되었다.

• 벤처창업연구
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• 제9권2호
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• pp.163-173
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• 2014

사회복지관련 예산의 급격한 증가가 함께 사회복지관련 사업도 다양한 분야로 확대되고 있다. 이러한 시점에서 사회복지정책을 수행하는 지자체인 서울시에 의한 지원과 보조사업 추진의 당위성 및 논거를 명확히 할 필요가 있다고 판단되며, 본 연구는 후생경제학 입장에서 사회복지관련 예산 지출이 서울지역 및 타 지역에 미치는 경제적 효과를 계량적으로 살펴보았다. 사회복지정책의 달성을 위한 예산 지출은 기업 및 개인의 소비행위를 연속적 및 직 간접적으로 파생시키게 되며, 본 연구에서는 서울지역 산업연관표를 재 작성하여 사회복지 예산 지출의 경제적 효과로써 생산, 부가가치, 고용, 취업 등에 얼마나 기여하는가를 계량적으로 산정하여 제시하였다. 지자체인 서울시의 사회복지관련 예산지출에 의해 연간 10조 2백억원의 생산을 유발시키며, 6조 4,936억원의 직간접 부가가치를 파급시키는 것으로 분석되었다. 또한 132,992.3명의 고용 및 203,430.3명의 취업을 창출시키는 것으로 산정되었다. 본 연구 결과는 사회복지 예산 지출을 소비지출로 인식하는 사회분위기 속에서 사회적 논란 야기 및 재정압박 요인으로 작용하는 현 시점에서 복지 분야에 대한 정부 및 서울시의 사회복지정책에 의한 개입 지원 보조의 당위성 논의의 타당성은 결국 실증적인 분석을 통하여 뒷받침될 수 있느냐에 달려 있다고 판단되며, 본 연구는 이를 위한 기초적 연구로서의 기초자료를 제시함에 그 의의가 있다. 또한 복지예산은 소멸성 지출이 아니며 우리나라 사회 경제에 다양한 영향을 파생시키는 중요한 산업임을 본 연구에서 확인할 수 있었으며, 지속적 연구를 통해 정책적 지원 및 사회적 합의가 필요하다.

• Asia pacific journal of information systems
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• 제19권2호
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• pp.179-193
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• 2009

As the common saying attests, a publish-or-perish world, publishing is absolutely critical for academic researchers' successful careers. It is the most objectively-accepted academic performance criteria and the most viable way to attain public and academic recognition. Asia Pacific Journal of Information Systems(APJIS) has been recognized as the most influential domestic journal in Korean MIS field since July, 1991. Therefore, publishing in APJIS means your research is original, valid, and contributive. While most researchers learn how to publish an article in APJIS through a repetitive review process, thereby improving their chance of the' accepted' through their personal trial and error experiences, such valuable lessons and know-how tend to be kept personally and rarely shared. However, useful insights into research and publication skills could be also gained from sharing others' errors, neglect, and misjudgments which are equally critical in improving researchers' knowledge in the field (Murthy and Wiggins, 2002). For this reason, other academic disciplines make systematic efforts to examine the paper review process of major journals and share the findings from these studies with the rest of the research community members (Beyer et al., 1995; Cummings et al, 1985; Daft, 1995; Jauch and Wall, 1989; Murthy and Wiggins, 2002). Recognizing the urgent need to provide such type of information to MIS research community in Korea, we have chosen the most influential academic journal, APJIS with an intention to share the answer to the following research question: "What are the common problems found in the manuscripts either 'rejected' or 'required a major revision' by APJIS reviewers?" This study analyzes the review results of manuscripts submitted to APJIS (from January, 2006 to October, 2008), particularly those that were 'rejected' or required a 'major revision' at the first round. Based on Daft's(1995) study, twelve most-likelihood problems were defined and used to analyze the reviews. The twelve criteria for classification, or "twelve problems", are as follows: No theory, Concepts and operationalization not in alignment, Insufficient definition--theory, Insufficient rationale--design, Macrostructure--organization and flow, Amateur style and tone, Inadequate research design, Not relevant to the field, Overengineering, Conclusions not in alignment, Cutting up the data, and Poor editorial practice. Upon the approval of the editorial board of APJIS, the total 252 reviews, including 11 cases of 2005 and 241 cases from July, 2006 to October, 2008, were received without any information about manuscripts, authors, or reviewers. Eleven cases of 2005 were used in the pilot test because the data of 2005 were not in complete enumeration, and the 241 reviews (113 cases of 'rejection' and 128 ones of 'major revision') of 2006, 2007, and 2008 were examined in this study. Our findings show that insufficient rationale-design(20.25%), no theory(18.45%), and insufficient definition--theory(15.69%) were the three leading reasons of 'rejection' and 'major revision.' Between these two results, the former followed the same order of three major reasons as an overall analysis (insufficient rationale-design, no theory, and insufficient definition-theory), but the latter followed the order of insufficient rationale--design, insufficient definition--theory, and no theory. Using Daft's three major skills-- 'theory skills', 'design skills', and 'communication skills'-- twelve criteria were reclassified into 'theory problems', 'design problems', and 'communication problems' to derive more practical implications of our findings. Our findings show that 'theory problems' occupied 43.48%, 'design problems' were 30.86%, and 'communication problems' were 25.86%. In general, the APJIS reviewers weigh each of these three problem areas almost equally. Comparing to other disciplines like management field shown in Daft's study, the portion of 'design problems' and 'communication problems' are much higher in manuscripts submitted to the APJIS than in those of Administrative Science Quarterly and Academy of Management Journal even though 'theory problems' are the most predominant in both disciplines.

• 설비공학논문집
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• 제22권7호
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• pp.492-507
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• 2010

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. 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) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery and piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.