• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.758-759
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• 1995

In large-scale industry such as shipbuilding, aircraft manufacturing, and construction industry etc., it is required to consider two or three-dimensional spatial availability as one of bottlenecked resource constraints. We call this kind of scheduling a spatial scheduling, which considers the dynamic spatial layouts of objects as well as the traditional resource constraints. Since 1991, we have researched on the spatial scheduling for shipbuilding plant (Lee & Lee, 1992; Lee et al., 1994, Lee et al., 1995). In this paper, we present the various issues of spatial scheduling for the researchers and developers attacking spatial scheduling problems.

• International Journal of High-Rise Buildings
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• v.12 no.4
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• pp.287-297
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• 2023

This paper briefly discusses current issues in wind engineering, including the enhancement of aerodynamic database and AI-assisted design, aerodynamic characteristics of tall buildings with atypical building shapes, application of computation fluid dynamics to wind engineering, evaluation of aerodynamic force coefficients based on a probabilistic method, estimation of tornadic wind speed (JEF scale) and effect of the Ekman Spiral on tall buildings.

• Journal of Environmental Science International
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• v.27 no.8
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• pp.711-721
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• 2018

In order to address housing issues, alleviate the concentration of urban populations, and resolve other issues regarding residential spaces, large residential complexes have been developed in Korea since the 1970s. The changes to the residential culture due to such development projects propagated rapidly, making the apartment complexes the most representative form of housing in Korea. In developing such large-scale complexes, plans for public open spaces, which play an important role in formulating the quality of residential environment, have been mostly the same, only utilizing the spaces remaining after planning other types of spaces. The current study looks at the case of Tama New Town development project, a Japanese new town development project that has a similar public open space system in large scale residential complex development projects in Korea. In doing so, the current study aims to identify the features of public open space plans. In the conclusion, the study first finds that various public open spaces must be reviewed and introduced in term of predicting social demands. Second, the study suggests the policy-makers should actively introduce pedestrian paths as a public open space. Third, the study deduces the planning implications of applying the principle of original landscape preservation.

• Journal of Construction Engineering and Project Management
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• v.4 no.4
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• pp.47-59
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• 2014

Client organization inadequate project planning before awarding the contract and insufficient monitoring and control system among the parties involved create severe problems. Ultimately, large-scale projects go beyond the expected cost and time control limits. This paper discusses the major issues involved with a large-scale Hydropower Project in Pakistan Public Sector environment. The latest approved Baseline Plan of project was reviewed and analyzed using Variance Analysis and Trend Analysis techniques in Primavera project management software to assess the efforts made of the parties involved. It was found that Project is 202% Cost overrun and 25% time delays from original contract award. After analysis of baseline plan and quantification of various variance issues in impacted activities, the questionnaire survey was conducted to identify the impact of causative factors. There were almost 17 most significant causative factors identified among 60 identified factors and responsibilities are assigned accordingly. At the end recommendations are made for strategic decisions as lessons learned during project evaluation.

• Journal of Music and Human Behavior
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• v.15 no.2
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• pp.41-67
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• 2018

The purpose of this case study was to examine how a supportive songwriting program could facilitate resilience for adolescents with school maladjustment. Participants included four middle school students with adaptive difficulties. The participants received eight 50-minute sessions of a supportive songwriting program. The program consisted of singing and discussing selected songs, followed by the participants creating their own lyrics about their current adaptation issues. The Resilience Scale for Adolescents was completed by each participant before and after the intervention, and the participants' lyrics were analyzed for how the factors of resilience were reflected in their lyrics. The results showed that all participants' scores on the resilience scale increased. It was also found that the factor on the resilience scale that increased the most for each participant was related to the issues expressed in their lyrics. The results suggest that the process of writing songs can be effective in eliciting adolescents' school related issues and accessing their positive resources, which can lead to behavioral and psychological improvements.

• Structural Engineering and Mechanics
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• v.6 no.5
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• pp.571-582
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• 1998

Testing of steel roof purlins is usually performed on full scale models in large vacuum test rigs. To undertake a comparison between web cleat connected purlins and flange bolted purlins a series of tests were performed on a 1:4 small scale model vacuum test rig. Various modelling issues need to be addressed to ensure reasonable comparison with actual constructed roof framing methods but still be suitable for an economical comparison between the connection methods. Model test results were supported by, and found to be in reasonable agreement with, deflection predictions from computer models based on finite element methods. This paper discusses the testing methods adopted and the value of small scale model testing programs as a means of obtaining comparisons between framing options.

• ETRI Journal
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• v.44 no.5
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• pp.780-793
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• 2022

Large-scale ontology management is one of the main issues when using ontology data practically. Although many approaches have been proposed in relational database management systems (RDBMSs) or object-oriented DBMSs (OODBMSs) to develop large-scale ontology management systems, they have several limitations because ontology data structures are intrinsically different from traditional data structures in RDBMSs or OODBMSs. In addition, users have difficulty using ontology data because many terminologies (ontology nodes) in large-scale ontology data match with a given string keyword. Therefore, in this study, we propose a (graph database-based ontology management system (GOMS) to efficiently manage large-scale ontology data. GOMS uses a graph DBMS and provides new query templates to help users find key concepts or instances. Furthermore, to run queries with multiple joins and path conditions efficiently, we propose GOMS encoding as a filtering tool and develop hash-based join processing algorithms in the graph DBMS. Finally, we experimentally show that GOMS can process various types of queries efficiently.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.354-360
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• 2009

The demands for large-scale construction projects such as Mega-projects are largely increasing due to the rapid growth of increasing populations as well as the need to replace existing buildings and infrastructure. Increasing costs of materials, supplies, and labors require the first cost estimates at the preliminary planning stage to be as accurate as possible. This paper presents the results obtained from the survey on evaluating nine critical success factors that influence the accurate first cost estimates for large-scale projects from practical experiences. It then examines the current cost structures of construction companies for large-scale projects, followed by the causes for cost and schedule overrun. Twenty completed surveys were collected and the Analytic Hierarchy Process was applied to analyze the data. The results indicate that technology issues, the contract type, and social and environmental impacts are the significant leading factors for accurate first cost estimates of large-scale construction projects.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.4
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• pp.117-124
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• 2016

Stress is resistance to stimuli to destroy a balance of mind and body in order to maintain an original steady state : A type of response and avoidance. Mild stress, which happens in tension, has a positive effect to improve concentration, but most of stress is likely to be a main factor to damage health. This is because it causes physical ailments and psychological diseases (e.g., depression, anger, frustration, loneliness, and anxiety). The purpose of this study is to analyze the difference between two groups, daytime and night university students, on ego-state, stressors, and stress coping types to improve their academic achievement by reducing their stress. There were 266 university students, who participated in a survey from November 30, 2015 until September 30, 2016. The study employed three measuring instruments : Ego-gram, stressor scale, and stress coping type scale. All the collected data were analyzed through regression analysis and t-test. The results of the regression analysis showed no significant differences in ego-state, stressors, and stress coping types between two groups. However, the results of t-test showed significant difference between the two groups : In terms of ego-state, a CP (Critical Parent) average of the night university students was significantly higher than the daytime university students'. Also, there is a significant difference in employment, future issues, and economic issues : the daytime university students considered employment and future issues more serious, while the night university students had more mental burdens of economic issues. When it comes to coping stress types, there was no significant difference between the two groups.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.11-25
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• 2015

The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011, caused by an earthquake and a subsequent tsunami, resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation, leakage from primary containment boundary to the reactor building, improper functioning of standby gas treatment system (SGTS), unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous, aqueous, and solid materials available for interaction, e.g., gas components, decontamination paint, aerosols, and water pools. In the light of the Fukushima accident, additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally, as more and more passive safety systems, such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors, identified hydrogen and fission product issues will need to be coupled with the operation of passive safety systems in phenomena oriented and coupled effects experiments. In the present paper, potential hydrogen and fission product issues raised by the Fukushima accident are discussed. The discussion focuses on hydrogen and fission product behavior inside nuclear power plant containments under severe accident conditions. The relevant experimental investigations conducted in the technical scale containment THAI (thermal hydraulics, hydrogen, aerosols, and iodine) test facility (9.2 m high, 3.2 m in diameter, and $60m^3$ volume) are discussed in the light of the Fukushima accident.