DEVELOPMENT OF THE MONTHLY AVERAGE DAILY SOLAR RADIATION MAP USING A-CBR, FEM, AND KRIGING METHOD

KOO, Choongwan,HONG, Taehoon,JEONG, Kwangbok,KIM, Jimin Vilnius Gediminas Technical University 2018 TECHNOLOGICAL AND ECONOMIC DEVELOPMENT OF ECONOMY Vol.24 No.2

<P>Photovoltaic (PV) system could be implemented to mitigate global warming and lack of energy. To maximize its effectiveness, the monthly average daily solar radiation (MADSR) should be accurately estimated, and then an accurate MADSR map could be developed for final decision-makers. However, there is a limitation in improving the accuracy of the MADSR map due to the lack of weather stations. This is because it is too expensive to measure the actual MADSR data using the remote sensors in all the sites where the PV system would be installed. Thus, this study aimed to develop the MADSR map with improved estimation accuracy using the advanced case-based reasoning (A-CBR), finite element method (FEM), and kriging method. This study was conducted in four steps: (i) data collection; (ii) estimation of the MADSR data in the 54 unmeasured locations using the A-CBR model; (iii) estimation of the MADSR data in the 89 unmeasured locations using the FEM model; and (iv) development of the MADSR map using the kriging method. Compared to the previous MADSR map, the proposed MADSR map was determined to be improved in terms of its estimation accuracy and classification level.</P>

CRITICAL ORGANIZATIONAL SUCCESS FACTORS FOR PUBLIC PRIVATE PARTNERSHIP PROJECTS - A COMPARISON OF SOLICITED AND UNSOLICITED PROPOSALS

Yun, Sungmin,Jung, Wooyong,Heon Han, Seung,Park, Heedae Vilnius Gediminas Technical University 2015 Journal of Civil Engineering and Management Vol.21 No.2

<P>Public Private Partnership (PPP) projects are typically initiated through solicited or unsolicited proposals. The difference between the processes according to the proposal mode often leads to different levels of involvement and responsibilities for the public and private sectors. However, no robust research exists to capture the differences, depending on the proposal mode, in the roles and involvement of project participants and the impact of those differences on project success. This study intends to explore the critical organizational success factors contributing to the success of PPP projects according to the proposal mode and to provide practical recommendations for project success from organizational perspectives. To assess the factors, 141 questionnaire surveys were conducted with participants in 32 PPP projects. The major findings indicated that “Project Implementation Capability” had the most critical influence on solicited projects, whereas “Risk Sharing and Mitigation Strategies” was the most significant in unsolicited projects. In addition, “Interorganization Coordination” among project participants was essential to the success for both solicited and unsolicited projects. Government roles and involvement were also critical, although their contributions were relatively less important than other critical organizational success factors. Based on the findings, practical recommendations were provided for the success of solicited and unsolicited projects.</P>

STOCHASTIC QUALITY-COST OPTIMIZATION SYSTEM HYBRIDIZING MULTI-OBJECTIVE GENETIC ALGORITHM AND QUALITY FUNCTION DEPLOYMENT

Lim, Tae-Kyung,Jang, Won-Suk,Choi, Jae-Ho,Lee, Dong-Eun Vilnius Gediminas Technical University 2015 Journal of Civil Engineering and Management Vol.21 No.4

<P>This paper introduces an automated tool, the stochastic quality-cost optimization (SQCO) system, that hybridizes multi-objective genetic algorithm (MOGA) and Quality Function Deployment (QFD). The system identifies the optimal trade-off between a construction owner’s satisfaction and a contractor’s satisfaction. It is important to reconcile the project participants’ conflicting interests because the construction owner aims to maximize the quality of construction while the contractor aims to minimize the cost of construction. MOGA is used to optimize resource allocation when owner satisfaction and contractor satisfaction are pursued at the same time under a limited budget. Multi-objective optimization is integrated with simulation to effectively deal with the uncertainties of the QFD input and the variability of the QFD output. This study is of value to practitioners because SQCO allows for the establishment of a quality plan that satisfies all of the multi project participants. The study is also of relevance to researchers in that it allows researchers to expeditiously identify an optimal design alternative of construction methods and operations. A test case implemented with a curtain-wall unit verifies the usability and validity of the system in practice.</P>

WIND-INDUCED RESPONSE CONTROL MODEL FOR HIGH-RISE BUILDINGS BASED ON RESIZING METHOD

Choi, Se Woon,Seo, Ji Hyun,Lee, Hong Min,Kim, Yousok,Park, Hyo Seon Vilnius Gediminas Technical University 2015 Journal of Civil Engineering and Management Vol.21 No.2

<P>A variety of methods have been applied to reduce the effect of the wind-induced vibration of a high-rise building as the excessive wind-induced vibration at the top of a high-rise building can cause physical and psychological discomfort to the user or the residents. For structural engineers, the most effective approach to control the wind-induced responses of high-rise buildings would be to control the stiffness or natural frequency of the building. This paper presents a practical design model to control the wind-induced responses of a high-rise building. In the model, the stiffness of a high-rise building is maximized to increase the natural frequency of the building by the resizing algorithm. The proposed design model is applied to control the wind-induced vibration of an actual 37-storey building during the initial stage of its structural design.</P>

APPLICATION OF AGENT-BASED MODELING AND SIMULATION TO UNDERSTANDING COMPLEX MANAGEMENT PROBLEMS IN CEM RESEARCH

Son, Jeongwook,Rojas, Eddy M.,Shin, Seung-Woo Vilnius Gediminas Technical University 2015 Journal of Civil Engineering and Management Vol.21 No.8

<P>As construction projects have become larger and more complex, they develop different features than smaller or traditional projects, which characterize them as complex systems. Still, Construction Engineering and Management (CEM) researchers have mostly relied on traditional approaches to investigate complex management problems, which might produce misleading results. This paper introduces Agent-Based Modeling and Simulation (ABMS) as a research method, and addresses how it could be applied to CEM research. With an illustrative example of the application of ABMS to CEM research, the theoretical background as well as the design, development, and test processes of ABMS are presented. We then made a recommendation on the promising research subjects in CEM area to which ABMS could be suitably applied.</P>

AN ALTERNATIVE APPROACH OF INPUT-OUTPUT TABLES TO DYNAMIC STRUCTURE CHANGES IN KOREAN IT INDUSTRIES

Cho, Byung-Sun,Cho, Sang Sup,Lee, Jungmann Vilnius Gediminas Technical University 2013 TECHNOLOGICAL AND ECONOMIC DEVELOPMENT OF ECONOMY Vol.19 No.2

<P>The structure of the IT industry has always evolved in line with technological progresses and changes in consumer preferences, as well as with regulatory trends. This is why, when assessing the effect that a new technology or industry policy may have on the national economy, companies and policy-makers need to consider dynamic structural changes affecting the IT industry. One of the most popular existing methods for economic impact analysis is based on a traditional input-output table, and is conducted over a period between the current time and a given time in the future. In this study, we compare the accuracy of RAS and Cross Entropy (CE), the two most widely employed methods for updating input-output (IO) tables, by applying them to Korean IT industries. The main results of this study are the following. In terms of the accuracy of input coefficient estimates, we have found that both the RAS and CE methods have a tendency to overestimate or underestimate them. When the Korean industry was first divided into fourteen sectors, and the RAS and CE methods were applied to each of the fourteen industries, it was difficult to discern a consistent trend for the two methods concerning their accuracy in estimation of input coefficients. Secondly, when used to update an IO table in which the IT industry is subdivided into IT equipment and services, neither the CE nor RAS method proved distinctly superior to the other. Third, in light of the above two findings, we concluded that updating IO tables is best done through a hybrid method combining the CE and RAS methods. This paper proposes a procedure consisting of two steps: IO tables are first updated using the two methods, which are once again updated by employing the OLS average approach through the use of optimal weights.</P>

AUTOMATIC DATA PROCESSING SYSTEM FOR INTEGRATED COST AND SCHEDULE CONTROL OF EXCAVATION WORKS IN NATM TUNNELS

Cho, Daegu,Cho, Hunhee,Kim, Daewon Vilnius Gediminas Technical University 2014 Journal of Civil Engineering and Management Vol.20 No.1

<P>A type-based system is widely used for cost and schedule control in the NATM (New Austrian Tunnelling Method) tunnel. This study raises several limitations of the type-based system: a broad level of control, a distributed approach to cost and schedule data, ad hoc management, and difficulty in deriving meaningful data. Integrated cost and schedule control promises a myriad of benefits on both information flow and construction management. Nevertheless, the integrated approach still seems to be a long way from common use in the construction industry because it requires considerable overhead effort to acquire, track, and analyze the integrated data. The objective of this study is to propose a new method to automate the required processes for implementing cost and schedule integration. We propose an operational-level automatic data processing system for cost and schedule integration. The proposed system consists of a real-time location system for detecting equipment locations, a wireless mesh network for transmitting the location signals to a field office, and a prototype model for transforming the signals to cost and schedule data. Technical feasibility is analyzed through a pilot project. The study offers a new approach to facilitating sensor technologies for cost and schedule integration.</P>

FEASIBILITY ANALYSIS MODEL FOR DEVELOPER-PROPOSED HOUSING PROJECTS IN THE REPUBLIC OF KOREA

Huh, Young-Ki,Hwang, Bon-Gang,Lee, Joong-Seok Vilnius Gediminas Technical University 2012 Journal of Civil Engineering and Management Vol.18 No.3

<P>The current construction industry recession in the republic of Korea has caused many construction companies to promote their own housing development projects. However, developers are still proposing many housing projects. While many studies on feasibility analysis for housing projects have been released, the focus was on economic feasibility, and factors related to developers have not been identified clearly enough to be used in practice. A feasibility analysis model is developed for apartment development projects in Korea to help main contractors make sound decisions on projects proposed by developers. To establish the model, 31 driving factors behind projects’ success, in seven categories, were identified through several meetings with experts and surveys. Factors such as ‘developer’, ‘method of raising funds’ and ‘method of contract’, which were considered less important in previous studies, were included in the model. Criteria for each factor were also developed to assess the factors quantitatively. Then, each factor was assigned a weight by applying the Analytic Hierarchy Process. ‘Salability’, ‘economic feasibility’, ‘site location’ and ‘method of raising funds’ have relatively high weights. Finally, based on a Monte Carlo simulation, a feasibility analysis model was established, providing a probability distribution of each project's grade. The model was applied to 12 housing projects constructed in Busan (seven successful projects and five abandoned projects) to verify its reliability. The application results showed that the model properly filtered projects that are unlikely to be profitable, indicating that it is reasonably reliable. Our model could thus be a useful tool for contractors, especially those with limited experience in analyzing project development feasibility.</P>

SPACE ZONING CONCEPT-BASED SCHEDULING MODEL FOR REPETITIVE CONSTRUCTION PROCESS

Cho, Kyuman,Hong, Taehoon,Hyun, Chang Taek Vilnius Gediminas Technical University 2013 Journal of Civil Engineering and Management Vol.19 No.3

<P>Many researchers have studied effective space zoning to reduce the duration of a construction project and interference among work tasks. These studies, however, attempted to plan the construction schedule using the space zoning concept based on network-based scheduling methods. Accordingly, it was difficult to reflect the representative characteristics of space zoning, such as iteration and overlapping. To overcome such limitations of existing methodologies and to achieve schedule reduction of a construction project by maximizing productivity, a Space zoning Concept-based scHEduling ModEl (SCHEME) for repetitive construction processes that adopt simulation techniques was developed in this study. The result of the application of the developed model to actual construction cases shows that the model reflects well the space-zoning characteristics, and in terms of the reduction of the construction duration, the model yielded a superior outcome in nonspace-zoning cases. The model developed in this study is expected to produce an excellent effect on the repetitive construction processes, in terms of construction duration.</P>

CONSTRUCTION KNOWLEDGE EVALUATION USING EXPERT INDEX

Park, Moonseo,Lee, Hyun-Soo,Kwon, Soonseok Vilnius Gediminas Technical University 2010 Journal of Civil Engineering and Management Vol.16 No.3

<P>While the current global economy can be characterized by the intensification of business competitiveness, leaner organizations, the convergence of products and services, and by vast technological developments, the risks and un‐certainties inherent in such a dynamic environment make the management of organizational knowledge even more crucial. Indeed, previous theoretical and empirical‐based studies have proven that knowledge leads to organizational success. Knowledge Management (KM) has particularly gained credence, and continues to generate interest, in academic and business circles. KM is of especial interest to project‐based industries such as construction, as the effective management of knowledge is critical to the survival and continued advancement of a company. In fact, in the construction industry, the implementation of a knowledge management system (KMS) is currently being considered, and an increasing number of companies have already proposed knowledge management initiatives. However, quality of information must take precedence over quantity, especially in the developmental phases of this KMS. Therefore, how to filter and accurately evaluate quantitative and qualitative data becomes a significant challenge. Yet, thus far, only a few studies examining the improvement of knowledge evaluation have been conducted and that researches only focus on the evaluation methods. This research addresses these issues by focusing on knowledge management and evaluation and by specifically addressing how evaluate knowledge effectively. Based on the Active Knowledge Management, this study proposes a process model for effectual construction knowledge evaluation using Expert Index (EI). EI is the level of specialty workers achieve in a certain field after engaging in a knowledge activity. The proposed model will not only enable precise evaluation, but will also provide stimulating knowledge activities; thus, if practically applied, this model could enhance actual organizational success. Santrauka Šiuolaikinei globaliajai ekonomikai būdingas konkurencijos didejimas, organizaciju lankstumas, gaminiu ir paslaugu suartejimas bei didžiuliai technologiniai laimejimai. Ši dinamine verslo aplinka kartu susijusi su rizika ir neapibrežtumais, didinančiais organizacijos žiniu vadybos (ŽV) svarba. Ankstesni teoriniai ir empiriniai tyrimai rodo, kad šios žinios ‐ organizacijos sekmes šaltinis. Žiniu vadyba tampa vis svarbesne akademinei ir verslo aplinkai. ŽV labai domimasi pramones šakose, kuriose didele reikšme turi projektai. Statyba yra viena iš tokiu šaku, joje veiksmingas žiniu valdymas, padedantis užtikrinti imoniu išlikima ir nuolatini vystymasi, yra labai svarbus. Šiuo metu statybos pramoneje diegiamos žiniu vadybos sistemos (ŽVS) ir vis daugiau imoniu pateikia ŽV siūlymu. Būtina siekti, kad žiniu kokybe būtu labiau vertinama nei žiniu kiekis, ypač ŽVS kūrimo tarpsniu. Todel kiekybinis ir kokybinis žiniu atsijojimas tampa rimta užduotimi. Deja, iki šiol atlikta mažai tyrimu, kaip gerinti žiniu vertinima. Atliekant šiuos tyrimus demesys telkiamas tik i žiniu vertinimo metodus. Straipsnyje efektyvus žiniu vertinimas nagrinejamas ŽV metodais. Pasitelkus aktyviaja ŽV kuriamas statybos žiniu vertinimo modelis ir taikomas ekspertu rodiklis (ER). ER išreiškia specialistu, isisavinančiu specifine informacija, žiniu lygi. Siūlomas modelis leis ne tik tiksliai vertinti, bet ir skatinti žiniu gavima. Taigi, taikant ši modeli praktikoje, bus galima gerinti imones veikla.</P>