• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.900-905
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• 2016

The field of power system harmonics has been receiving a great deal of attention recently. This is primarily due to the fact that non-linear (or harmonic-producing) loads comprise an ever-increasing portion of what is handled at a typical industrial plant. The incidence rate of harmonic-related problems is low, but awareness of harmonic issues can still help increase offshore power plant system reliability. On the rare occasion that harmonics become a problem, this is either due to the magnitude of harmonics produced or power system resonance. This harmonic study used an electrical configuration for the offloading scenario of a Floating LNG (FLNG) unit, considering power load. This electrical network configuration is visible in the electrical network load flow study part of the project. This study has been carried out to evaluate the performance of an electric power system, focusing on the harmonic efficiency of an electrically driven motor system to ensure offshore plant safety. In addition, the design part of this study analyzed the electric power system of an FLNG unit to improve the safety of operation and maintenance.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.186-193
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• 2010

In order to examine the traits of sluice gate water control, halophyte community formation and their inter-relations in Saemangeum, both water level condition and halophyte community formation were analyzed periodically and spatially on the topographic map with Surfer, Saemageum Spatial Analysis System, and related field reports. The traits of water level condition are that average water level in the growing period of halophytes was similar to annual average water level, annual low level and high level appeared in the growing period, and water level was usually maintained within a range of -1.0m~0.5m above mean sea level, but it has changed more frequently year by year. Routine water level control, natural disaster prevention, construction, and civil appeal took major percentages of the reasons for sluice gate's opening and shutting. Since 2007, not only the overall control frequency of sluice gate but also its control frequency for construction and natural disaster prevention have increased outstandingly. Halophyte community had formed at a rate of 1,209ha/year in the 4,315 ha land in 2008, 6.3 times larger than in 2005, and 2,382 ha above around 1.0m was estimated to be artificially vegetated, 89.1 % of the 2,673ha-size sown area. High water level was found to be a more possible determinant than average water level or low water level in halophyte community formation and it was thought to be secondary factors whether tillage was conducted or/and whether surface sealing formed.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.1
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• pp.35-51
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• 2017

Street gardens, a series of streetscape improvement projects led by Seoul City Government, are initiated for the purpose of providing aesthetic satisfaction and mental refreshment to pedestrians. In order to investigate whether street gardens indeed promote the psychological health of the users, questionnaire surveys were conducted on three selected street gardens - at Gangnam-daero, Digital-ro, and Teheranro - and their comparison sites located on the same streets, which have a similar physical environment but without a street garden. The survey questionnaires, based on Attention Restoration Theory, were composed of Perceived Restorativeness Scale-11 with the eleven individual questions grouped into four categories: 'Fascination', 'Being away', 'Coherence', and 'Scope'. The survey questionnaires also ask about physical components that promote psychological improvement in the aforementioned categories. The collected data was analyzed with factor analysis, reliability analysis, and independent t-test. The results suggested that street gardens had a relatively positive effect on the psychological restorativeness of the users. In particular, they gave fascination and interest to the users. However, they did not offer a feeling of being away to the users, which revealed the limitation in the psychological improvement effect of street gardens. The physical components of the street garden that have led the psychological restorativeness effect were wooden bench, tree, and flower. This result corresponds to an extant theory that natural factors have a positive effect on the psychological restorativeness within a hardscape. This research will shed light on the planning and design guidelines for the street garden project.

• Plant Journal
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• v.11 no.1
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• pp.39-49
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• 2015

The objective of this study is to improve the classification structure of commodity code for piping material management which is considered as the fundamental of commodity code and piping material management system. It enhances the efficiency of piping material management directly or indirectly affecting the engineering, procurement and construction in a petrochemical plant projects. To establish an improved code classification structure, this study identifies the problems of former code classification structure in details, as well as the characteristics of other domestic and global EPC company's code classification structures and presents the improved direction considering the recently mega-sized and specialized projects. Accordingly, to efficiently enhance piping material management, the improved code classification structures have been derived from defining suitable code classification structure for specific piping component, adding more standard attribute, expanding the number of code digits and classifying code hierarchy. The results of applying the improved classification structure of commodity code to on-going project have led to reduce the rate of rework from 4.98% to 2.48% for developing purchase description and also have saved working time for executing piping design by 3D modeling from 6 months by two persons to 4 months by a person which is decreased 67% consequently. In addition, the structures of pyramid code management have resulted to accumulation and analysis of the various piping data for other disciplines such as procurement and estimation team which require commodity code information through the company's material control system.

• Journal of Distribution Science
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• v.13 no.12
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• pp.65-71
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• 2015

Purpose - Domestic cooperatives tend to increase during the establishment of cooperatives and gradually through the basic law of social needs. However, only cooperatives' qualitative grow this secured without blessings, and their quantitative growth through government support is questionable. The purpose of this study is to analyze the agricultural cooperatives established through the Distribution System Cooperatives Basic Law, which was enacted in January 2012. Subsequently, establishing agricultural cooperatives was done briskly. However, cooperatives established rapidly after the founding of the Basic Law encountered problems. Research design, data, and methodology - To assess the performance of selected agricultural cooperatives, data were analyzed using the methodological Analytic Hierarchy Process (AHP) approach. The AHP is a set of systematic procedures to hierarchically analyze the elements of any problem. Using a survey on expertise, a series of comparative determinations of each pair is performed to evaluate the relative strengths and the strengths of the impact between elements within the hierarchy. A survey was conducted on 10 small agricultural cooperatives using AHP analysis for the examination. The purpose of such research and analysis is to recommend a direction for future policies aimed at small agricultural cooperatives. Result - This study applied three types of policy evaluation criterion, including market expansions, organizations, and cooperative projects, and 12 types of small agricultural cooperative policy measures. Market expansion policies for agricultural cooperatives are classified into four categories: school meals, direct transactions, shopping malls, and wholesale markets. Organizational policies for agricultural cooperatives are classified into four types: existing sales channel management, education, preventing free riding, and enlarging members. Cooperative project policies in agricultural cooperatives are classified into four policy areas: cooperation between cooperatives, community contribution, joint businesses, and government links. In this paper, the growth priority in agricultural cooperative policies is analyzed by applying policy evaluation criteria on the basis of a survey on expertise. The priorities of the policy program are also analyzed using a decision analytic hierarchy process. The results indicate that market expansion is the most important policy evaluation criterion therefore, improving direct transactions, school meals, management of existing sales channels, and shopping malls are crucial policy measures. In contrast, the cooperation of cooperatives, expansion of union members, and cooperation with the government were found to have low priority. Conclusions - Agricultural cooperatives should develop plans as follows. Small agricultural cooperatives need to secure school meals and direct transactions for market expansion, restructure marketing strategies to manage existing sales channels, and, finally, increase education and training for sustainable organizational development. This study has the following limitations. Because the subject of the investigation is a new cooperative, determining its sustainable growth is difficult. Therefore, through analysis and a continuous study of cooperatives, future research is expected to show that modifying the direction of agriculture cooperatives is necessary.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.27 no.4
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• pp.278-305
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• 2016

Objective: The aim of this systematic literature review is to analyze the psychosocial interventions for children and adolescents after disasters. Methods: We conducted a review of the extant research literature from 1991 to 2015 via a comprehensive search of the MEDLINE, EMBASE, Cochrane CENTRAL, PubMed and PsyclNFO databases. The keywords employed in this research included: 'child', 'adolescent', 'youth', 'disaster', 'posttraumatic', 'psychosocial', 'therapy' and 'intervention'. The researchers followed the PRISMA guidelines. A total of 850 articles were screened for their eligibility and fifty-nine were found to meet the study criteria. The final data analysis was performed based on the disaster type, study design, type of intervention, sample size, age, school grade, number of sessions, setting of intervention delivery, providers, approach and parent involvement. Results: Countries worldwide have experienced various kinds of disasters, including earthquakes, hurricanes, vessel accidents, tornados, tsunamis, volcanic eruptions, war, fire, terrorism, and traffic accidents. The types of psychosocial intervention that were conducted after these disasters included: psychological first aid, psychological debriefing, psychoeducation, trauma focused cognitive behavior therapy, eye movement desensitization reprocessing, prolonged exposure therapy, group play therapy and arts therapy, project interventions, school-based interventions and web-based interventions. Conclusion: The findings of the systematic literature review suggest that an appropriate psychosocial intervention could be utilized as evidence-based mental health treatment for children and adolescents after disasters.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.791-800
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• 2013

Needs for developing a better way of cost estimating process for public construction projects have been widely recognized. Those needs are mainly from the early phases of the project through the construction life cycle due to the its importance to the control process. In contrast to the traditional estimating method based on unit-price references, this research utilized this following process. The first step is analyzing the real cost data from actual cost activities (2000~2010) about the statement of P.S.C(Prestressed Concrete) Box Girder Bridge. The collected data was broken into four categories based on technical construction methods such as I.L.M(Incremental Launching Method), M.S.S(Movable Scaffolding System), F.S.M(Full Staging Method), and F.C.M(Free Cantilever Method). The second, actual design documents including the actual cost estimating documents, drawings and specifications were carefully reviewed to cluster the cost itemized statement from four categories. It was also attempted to seek the proper breakdown of standard works that are responsible for more than 95 percentage in each categories in terms of its cost. The third, this research comes up the index for standard unit materials and unit price of standard work and develops the approximate estimating model applying for the specification(length and breadth of bridges) per square area that the user takes as well as suggests the practical application plan within the original time alloted.

• Journal of the Korea Society for Simulation
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• v.15 no.2
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• pp.59-69
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• 2006

Component-based software development is introduced as a new development paradigm in software development method. This approach is different from existing software development approach because it is based on reusable and autonomous unit, component. Therefore, component-based development(CBD)is divided into two stages; component development process and component assembly process; application development process. Component development process is the core of CBD because component has a key for good software. Currently many methodologies or tools have been introduced by various academies or industries. However, those don't suggest systematic and flexible modeling techniques adaptable easily into component development project. Existing approaches have a unique orarbitrary modeling technique or provide heuristic guidelines for component modeling. As a result, many component developers are faced with a difficult problems; how to developcomponent models, when develop which diagrams, and so on. In order to address this problem, we suggest a meta-model driven approach for component development in this paper. We provide meta-models according to both layer and development phase. We expect that suggested meta-models allow component developers to develop appropriate models of the time.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.21-33
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• 2018

In 2018, the real estate markets have hardly been transacted according to the government's tight regulations of real estates, and have the high possibility to reach a low hit due to the hike of loan interest rates following the U. S rise of base money rate. The key profits for the large construction companies mainly come from the overseas plant projects and the domestic non-governmental construction projects. They suffered a lot such as the lowering of their credit ratings due to the large losses caused by the frquent design changes and work delay. Even in the domestic non-governmental construction projects, the general business risks are on the rise due to the property marketing moving over to the decreasing phase. The small and medium sized security companies has realized a lot of operaring profits as they participated in the PF market to make up for the losses in the securities trading business. But, now as the housing market is not so good around the nation except Seoul and the financial states of large construction companies are not good enough, they can face the liquidity crisis if there happens the problems in the PF backed securities which they have handled. As Korean economy experienced the crisis in the savings banks before, it is recommended that Financial Supervisory Service proposes the preemptive control method and supervision direction to overcome the crisis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.3A
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• pp.179-184
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• 2003

In this paper, an asymmetric topology of MMIC SPDT switch was proposed to increase the isolation in the receiving path and decrease the insertion loss with higher P1dB in the transmitting path for the ISM band. This SPDT switch was implemented with 0.5㎛ GaAs MESFETs processed by ETRI for the IDEC MPW project. For the receiving path the measured insertion losses were 1.518dB at 3GHz and 1.777dB at 5.75GHz and the isolations were 38.474dB at 3GHz and 29.125dB at 5.75GHz. For the transmitting path the insertion losses were 0.916dB at 3GHz and 1.162dB at 5.75GHz and the isolations were 23.259dB at 3GHz and 16.632dB at 5.75GHz. Compared to the symmetric topology the isolations of the receiving path for the asymmetric one were improved by 15.9dB at 3GHz and 11.9dB at 5.75GHz and its insertion loss was increased by about 0.6dB. In addition, P1dB of 21.5 dBm for the transmitting path was obtained, which is increased by 3.86dB compared to the symmetric one.