• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.5 s.98
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• pp.519-526
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• 2005

Recently, the interest on the comfortable dwelling environment is increasing and the effort to solve the problem of exterior noise was tried. The propose of this study is to suggest the design of balcony window in apartment and to evaluate the sound insulation of it. So, we designed five types of balcony window which were considered not only sound insulation but ventilation. The sound reduction index of window was evaluated by the measurement in mock-up room. The results showed that case 2 improved about 6 dB in the weighted apparent sound reduction index than case 1, and case 3 reduced about $39 \%$ in construction cost than case 4.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.126-132
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• 2005

The purpose of this study is to propose a method to evaluate task complexity using CIFs(Complexity Influencing Factors). We developed a method that CIFs can be used in the evaluation of task complexity using fuzzy linguistic approach. That is, a fuzzy linguistic multi-criteria method to assess task complexity in a specific task situation was proposed. The CIFs luting was assessed in linguistic terms, which are described by fuzzy numbers with triangular and trapezoidal membership function. A fuzzy weighted average algorithm, based on the extension principle, was employed to aggregate these fuzzy numbers. Finally, the method was validated by experimental approach. In the result, it was validated that TCIM(Tink Complexity Index Method) is an efficient method to evaluate task complexity because the correlation coefficient between task performance time and TCI(Task Complexity Index) was 0.699.

• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.4
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• pp.374-385
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• 2012

The indoor noise of a ship is usually determined using the A-weighted sound pressure level. However, in order to better understand this phenomenon, evaluation parameters that more accurately reflect the human sense of hearing are required. To find the level of the satisfaction index of the noise inside a naval vessel such as "Loudness" and "Annoyance", psycho-acoustic evaluation of various sound recordings from the naval vessel was performed in a laboratory. The objective of this paper is to develop a single index of "Loudness" and "Annoyance" for noise inside a naval vessel according to a psycho-acoustic evaluation by using psychological responses such as Noise Rating (NR), Noise Criterion (NC), Room Criterion (RC), Preferred Speech Interference Level (PSIL) and loudness level. Additionally, in order to determine a single index of satisfaction for noise such as "Loudness" and "Annoyance", with respect to a human's sense of hearing, a back-propagation neural network is applied.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.445-450
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• 2004

Recently, the interest on the comfortable dwelling environment is increasing and the effort to solve the problem of exterior noise was tried. The propose of this study is to suggest the design of balcony window in apartment and to evaluate the sound insulation of it. So, we designed five types of balcony window which were considered not only sound insulation but ventilation. The sound reduction index of window was evaluated by the measurement in mock-up room. The results showed that case 2 improved about 6dB in the weighted apparent sound reduction index than case 1, and case 3 reduced about 39% in construction cost than case 4.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.1070-1075
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• 2005

The evaluation items to assess the consumer needs are thought to be varied depending on their age, education and income. It should be noted that consumer needs are getting too diversified to notice them in time due to the rapid economic, social and cultural development. It is, therefore, considered improper to try to assess the level of consumer satisfaction and correct consumer needs by employing one evaluation method for the vastly diversified consumer types. This research is going to conduct a written questionnaire survey to the apartment dwellers in order to identify like dweller groups according to their age, income and education. Then the scope of personal characteristics of each group will be identified and the importance assessment model will be developed. Then the items on the POE will be weighted according to the assessed importance. Finally a method of developing the customer satisfaction index will be produced to quantify how much the consumers are satisfied with the project.

• Journal of the Korean Data and Information Science Society
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• v.21 no.6
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• pp.1171-1180
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• 2010

It is well known that the asymptotic convergence rates of nonparametric regression estimator gets worse as the dimension of covariates gets larger. One possible way to overcome this problem is reducing the dimension of covariates by using single index models. Two coefficient estimation methods in single index models are introduced. One is semiparametric least square estimation method, which tries to find approximate solution by using iterative computation. The other one is weighted average derivative estimation method, which is non-iterative method. Both of these methods offer the parametric convergence rate to normal distribution. However, practical comparison of these two methods has not been done yet. In this article, we compare these methods by examining the variances of estimators in various models.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.4
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• pp.235-246
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• 2021

This study investigated the impact of baseflow on fish community in the Ungcheon stream (16.5 km long) located downstream of the Boryeong Dam, Korea. Based on field monitoring, there were five dominant fish species in the Ungcheon Stream accounting for 75% of the total fish community: Zacco platypus, Zacco koreanus, Tridentiger brevispinis, Rhinogobius brunneus, and Pungtungia herzi. These five fish species were selected as target species. HydroGeoSphere (HGS) and River2D models were used for hydrologic and hydraulic simulations, respectively. A habitat suitability index model was used to simulate fish habitat. To assess the impact of baseflow, each representative discharge was examined with or without baseflow. The HGS model was used to calculate baseflow within the study reach. This baseflow was observed to increase gradually with longitudinal distance. Validation of the hydraulic model dem onstrated that computed water surface elevated when baseflow was included, which was in good agreement with measured data, as opposed to the result when baseflow was excluded. Composite suitability index distributions and weighted usable area in the study reach were presented for target species. Simulations indicated that the baseflow significantly increased habitat suitability for the entire fish community. These results demonstrate that there should be a substantial focus on the baseflow for physical habitat simulation.

• Korean Journal of Social Welfare Studies
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• v.42 no.1
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• pp.151-177
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• 2011

With the expansion of Voucher program, academic and practical concerns of performance evaluation of voucher service has been more emphasized. Accordingly, client satisfaction survey are expanding these days, but the study of client satisfaction as a performance indicator aimed at service client has not been yet conducted systematically. The purpose of this study is to develop Satisfaction Index, targeting at client of community-development voucher program in Community Service Investment Project conducted by the Ministry of Health and Welfare. Data were collected from 1800 client of community-development voucher program. This study summarized theoretically many kinds of satisfaction measurement and composed the Satisfaction Index reflecting characteristics of Voucher. By the item analysis and reliability analysis, the element satisfaction was identified as homogeneous items. General satisfaction were obtained using element satisfaction and overall satisfaction, it was found to be valid through the evaluation of convergent and discriminant validity as a tool for satisfaction. This study suggest using the '1step weighted approach' than '2step weighted approach' having weakness of complex overlapping manner.

• Steel and Composite Structures
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• v.14 no.4
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• pp.397-408
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• 2013

This paper deals with multiobjective optimization of symmetrically laminated composite truncated circular conical shells subjected to external uniform pressure load and thermal load. The design objective is the maximization of the weighted sum of the critical buckling load and fundamental frequency. The design variable is the fibre orientations in the layers. The performance index is formulated as the weighted sum of individual objectives in order to obtain optimal solutions of the design problem. The first-order shear deformation theory (FSDT) is used in the mathematical formulation of laminated truncated conical shells. Finally, the effect of different weighting factors, length-to-radius ratio, semi-cone angle and boundary conditions on the optimal design is investigated and the results are compared.

• Steel and Composite Structures
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• v.14 no.2
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• pp.121-132
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• 2013

This paper deals with multiobjective optimization of symmetrically laminated composite angle-ply annular sector plates subjected to axial uniform pressure load and thermal load. The design objective is the maximization of the weighted sum of the critical buckling load and fundamental frequency. The design variable is the fibre orientations in the layers. The performance index is formulated as the weighted sum of individual objectives in order to obtain the optimum solutions of the design problem. The first-order shear deformation theory is used for the mathematical formulation. Finally, the effects of different weighting factors, annularity, sector angle and boundary conditions on the optimal design are investigated and the results are compared.