• Journal of Environmental Impact Assessment
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• v.15 no.6
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• pp.435-441
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• 2006

For the calibration of rainfall-runoff model, automatic calibration methods are used instead of manual calibration to obtain the reliable modeling results. When mathematical programming techniques such as linear programming and nonlinear programming are applied, there is a possibility to arrive at the local optimum. To solve this problem, genetic algorithm is introduced in this study. It is very simple and easy to understand but also applicable to any complicated mathematical problem, and it can find out the global optimum solution effectively. The objective of this study is to develope a parameter optimization program that integrate a genetic algorithm and a rainfall-runoff model. The program can calibrate the various parameters related to the runoff process automatically. As a rainfall-runoff model, SWMM is applied. The automatic calibration program developed in this study is applied to the Jangcheon watershed flowing into the Youngrang Lake that is in the eutrophic state. Runoff surveys were carried out for two storm events on the Jangcheon watershed. The peak flow and runoff volume estimated by the calibrated model with the survey data shows good agreement with the observed values.

• Computers and Concrete
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• v.5 no.6
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• pp.573-597
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• 2008

Among artificial intelligence-based computational techniques, adaptive neuro-fuzzy inference systems (ANFIS) are particularly suitable for modelling complex systems with known input-output data sets. Such systems can be efficient in modelling non-linear, complex and ambiguous behaviour of cement-based materials undergoing single, dual or multiple damage factors of different forms (chemical, physical and structural). Due to the well-known complexity of sulfate attack on cement-based materials, the current work investigates the use of ANFIS to model the behaviour of a wide range of self-consolidating concrete (SCC) mixture designs under various high-concentration sodium sulfate exposure regimes including full immersion, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading. Three ANFIS models have been developed to predict the expansion, reduction in elastic dynamic modulus, and starting time of failure of the tested SCC specimens under the various high-concentration sodium sulfate exposure regimes. A fuzzy inference system was also developed to predict the level of aggression of environmental conditions associated with very severe sodium sulfate attack based on temperature, relative humidity and degree of wetting-drying. The results show that predictions of the ANFIS and fuzzy inference systems were rational and accurate, with errors not exceeding 5%. Sensitivity analyses showed that the trends of results given by the models had good agreement with actual experimental results and with thermal, mineralogical and micro-analytical studies.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.3
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• pp.29-36
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• 2009

This study aims at the contribution to introduction of facilities and planning for the promotion of the exchange between city and rural community and the promotion of the rural areas. In order to understand the object of the Setagaya Ward Health Village and the management and the effects of facilities, I investigated the documentation, field work and interviews with the persons related. The Setagaya Ward Health Village has been steadily managing the exchange base facilities and the special enterprises, and operating the manager and promotion committees for the projects. Consequently, many tourism facilities and new enterprises such as the Setagaya-Kawaba Corporation were established in the rural areas and they developed into an active region which has abundant jobs available and attracts about 700,000 visitors a year. In conclusion, it is important to make a main body to manage professionally the future plan of facilities which involve image of the regional future and conform to the law. And the facilities should contribute to the economic development of rural areas in consideration of the environment and culture.

• Smart Structures and Systems
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• v.13 no.6
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• pp.943-957
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• 2014

When subjected to fatigue loading, the main failure mode of partially prestressed concrete (PPC) structure is the fatigue fracture of tensile reinforcement. Therefore, monitoring and evaluation of the steel stresses/strains in the structure are essential issues for structural design and healthy assessment. The current study experimentally investigates the possibility of using fiber Bragg grating (FBG) sensors to measure the steel strains in PPC beams in the process of fatigue loading. Six full-scale post-tensioned PPC beams were exposed to fatigue loading. Within the beams, the FBG and resistance strain gauge (RSG) sensors were independently bonded onto the surface of tensile reinforcements. A good agreement was found between the recorded results from the two different sensors. Moreover, FBG sensors show relatively good resistance to fatigue loading compared with RSG sensors, indicating that FBG sensors possess the capability for long-term health monitoring of the tensile reinforcement in PPC structures. Apart from the above findings, it can also be found that during the fatigue loading, there is stress redistribution between prestressed and non-prestressed reinforcements, and the residual strain emerges in the non-prestressed reinforcement. This phenomenon can bring about an increase of the steel stress in the non-prestressed reinforcement.

• Physical Therapy Korea
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• v.10 no.1
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• pp.139-158
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• 2003

This study evaluated the community-based rehabilitation services provided by the Wonju Public Health Center from Jan. 2000 to Dec. 2002. Ninety-four persons with disabilities dwelling in the community participated and the surveys were completed in an interview during home visits. The respondents' demographic, socio-economic, and medical characteristics, rehabilitation service received, willingness to receive home-visit rehabilitation services, and satisfaction with the rehabilitation services were analyzed by frequency and percentage. A Likert scoring system consisting of five agreement-disagreement categories was applied to each item, consisting of Very Satisfied, Satisfied, So-So, Poorly Satisfied, and Very Poorly Satisfied. The major findings were as follows: 1) The rehabilitation services used included medical rehabilitation (26.9%), followed by social assistance (23.5%), diagnosis by a physician at home (17.3%), medical examination (12.3%), housekeeping services (6.2%), and vocational and educational rehabilitation (3.5%). 2) Of the medical services, the respondents desired physical therapy at home and free rental of rehabilitation equipment, such as wheelchairs, canes, walkers, the most, followed by home visit occupational therapy, nursing services, and oriental medicine service in descending order. 3) Some of the respondents expressed so-so satisfaction (50.0%) or dissatisfaction (16.9%) with the rehabilitation services provided by the Wonju Public Health Center. These findings should prove useful when planning or extending community-based rehabilitation programs for the homebound disabled in the community.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1685-1689
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• 2016

Physical wedges still can be used as missing tissue compensators or filters to alter the shape of isodose curves in a target volume to reach an optimal radiotherapy plan without creating a hotspot. The aim of this study was to investigate the dosimetric properties of physical wedges filters such as off-axis photon fluence, photon spectrum, output factor and half value layer. The photon beam quality of a 6 MV Primus Siemens modified by 150 and 450 physical wedges was studied with BEAMnrc Monte Carlo (MC) code. The calculated present depth dose and dose profile curves for open and wedged photon beam were in good agreement with the measurements. Increase of wedge angle increased the beam hardening and this effect was more pronounced at the heal region. Using such an accurate MC model to determine of wedge factors and implementation of it as a calculation algorithm in the future treatment planning systems is recommended.

• Journal of Construction Engineering and Project Management
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• v.3 no.4
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• pp.5-11
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• 2013

Construction industry is overwhelmed by delay and often has suffered cost and time overrun. In this context, Last Planner System (LPS) has been considered as a very useful tool for the management of the construction process. Many previous studies have reported its effectiveness in construction performance. This study aims to evaluate the level of importance of the Last Planner processes in the Vietnam construction industry (VCI), and analyze the existing barriers when implementing these processes in construction management. These barriers were collected based on previous studies from International Group for Lean Construction (IGLC). A survey was carried out through questionnaire. The respondents are been experienced people in construction project management. There are four processes of LPS that were investigated including master schedule, phase schedule, lookahead plan, and weekly work plan. The results showed that master schedule is the most important item when performing a construction project in the VCI. The highest degree of agreement belongs to 'owner - contractor' pair with 77.1% importance indices; whereas the lowest belongs to 'consultants - contractors' pair with 63.8% importance indices. Eventually, three barrier factors were extracted from factor analysis technique with 62.2% of variance explained.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.5
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• pp.145-154
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• 2020

The purpose of this study is to analyze how the problems caused by overtourism affect the quality of life of Jeju residents and their perceptions of the overtourism phenomenon by exploring related factors for future policy implications. In the research model, each independent factor related to tourists affects the quality of life of residents, and the mediation variable (QoL) ultimately agrees with overtourism. This study uses Partial Least Squares-Structural Equation Modeling (PLS-SEM), which is less influenced by the sample size. The research is based on 360 questionnaires. The test results showed that cultural factors affected the QoL statistically at 1% significance level, and economic factors were significant at 5%. The quality of life variable affects the agreement of overtourism (p-value 1% significance level). An indirect effect analysis on whether each independent factor affects the overtourism factor through the parameter of the QoL of the residents showed that the cultural factor at 5% level statistically affected it, and economic factors were significant at 10%. In conclusion, we recommend implementing both economic and cultural factors to reduce the negative perception of overtourism for the policy planning. Further research in multiple aspects should be continued to overcome the vulnerability of the Island destination tourism.

• Korean System Dynamics Review
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• v.7 no.1
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• pp.91-118
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• 2006

The purpose of this study is to find what factors are directly related to the delay of public projects, usually going beyond the planned deadline and budget. From a series of System Dynamics simulation works applied to the Cheongju Cremation Project, the research finds that the negative externalities originated from the adjacent location of the LULU(locally unwanted land use) facilities have exerted significant influence on dynamic perceptions of key stakeholders, typically resulting in project delay. As shown repeated experiments, the proposed negotiation-based models would produce relatively higher planning performance level than the typical approaches hinged on the administrative-expediency tactics. Even though the former may require more human and material resources in the very beginning stage, as they have to deal with diverse grievances raised by major stake-holders, most of them would bound for strengthening reinforcing loops within the complex structure. These results also imply that negotiation or consensus-building approaches would enhance mutual agreement among stake-holders, upgrading the overall quality of project management.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1183-1189
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• 2012

The KOrea Insecticide Exposure Model (KOIEM) was developed to facilitate ecological risk-based management of Korean insecticides. KOIEM, applied as a multimedia fate model, evaluates water, soil, air, and vegetation compartments based on three water-body types (streams, ditches, and ponds). Deltamethrin, a pyrethroid insecticide, was used to evaluate and create the model parameters. After exposure of both the stream and the ditch to deltamethrin, the KOIEM-predicted concentrations and the observed levels were in agreement. The model was also evaluated using the accuracy factor (AF), which was 4.32 and 0.35 for the stream and ditch, respectively. Ecological risk assessment was also performed to evaluate the application of KOIEM for four popular South Korean insecticides (cypermethrin, deltamethrin, diazinon, and permethrin). Despite the insecticides having low PECs in water, their risk quotients were typically above 1.0. Thus, KOIEM modification would be required in further studies to account for spatial variation.