• 대한전기학회논문지:전력기술부문A
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• 제49권5호
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• pp.226-232
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• 2000

This paper presents application results of the augmented matrix eigen-sensitivity theories to TCSC siting problem for damping the inter-area low frequency oscillation in the large KEPCO system. First and second-order eigen-sensitivities of the inter-area low frequency oscillation in the large KEPCO system. First and second-order eigen-sensitivities of the inter-area mode are computed fro changes in susceptance of the transmission lines. The lines having high sensitivity are chosen as the initial candidates for installing TCSC. Then for each of the chosen candidates, Bodeplot of the transfer function with line susceptance as the input and the bus voltage at one side of the line as the output is computed. Using the Bode plots, the lines having any zeros near the inter-area mode are screened out since design of TCSC controller is very difficult in such a case. The $H_{\infty}$ TCSC controller installed at any finally chosen candidate is found to be effective in damping the inter-area oscillation, and the proposed TCSC siting algorithm is proved to be valid. Design of $H_{\infty}$ controller is described in Part IIof this paper.

• Structural Engineering and Mechanics
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• 제30권4호
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• pp.445-466
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• 2008

This paper presents a novel structural damage detection method with a new damage index based on the statistical moments of dynamic responses of a structure under a random excitation. After a brief introduction to statistical moment theory, the principle of the new method is put forward in terms of a single-degree-of-freedom (SDOF) system. The sensitivity of statistical moment to structural damage is discussed for various types of structural responses and different orders of statistical moment. The formulae for statistical moment-based damage detection are derived. The effect of measurement noise on damage detection is ascertained. The new damage index and the proposed statistical moment-based damage detection method are then extended to multi-degree-of-freedom (MDOF) systems with resort to the leastsquares method. As numerical studies, the proposed method is applied to both single and multi-story shear buildings. Numerical results show that the fourth-order statistical moment of story drifts is a more sensitive indicator to structural stiffness reduction than the natural frequencies, the second order moment of story drift, and the fourth-order moments of velocity and acceleration responses of the shear building. The fourth-order statistical moment of story drifts can be used to accurately identify both location and severity of structural stiffness reduction of the shear building. Furthermore, a significant advantage of the proposed damage detection method lies in that it is insensitive to measurement noise.

• 복식문화연구
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• 제18권5호
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• pp.809-823
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• 2010

The 21st century is the age of culture and sensitivity. As the interest in the art and culture grows, Artygen who prefers artistic designs grow in number. The desire to enjoy life from the increase of leisure time and financial afford ability created a new trend of party culture. This study analyzes the characteristics of Artygen who pursues artistic sense and sensitivity and suggests party-wear designs that please Artygen and accentuate individuality and personal preferences in a party, which is a type of popular entertainment these days. Through literature review, the background of Artygen and party was examined; First, in order to analyze the feature of art designs, photos of products that were in fashion from 2007 to 2009, (during which the term, 'Artygen', was coined) were collected. Second, in order to analyze the party-wear designs, photos of party-wear in wine party and club party popular among young people in the 20~30's were collected. Through the analysis, the party-wears targeting Artygen was developed based on the characteristics of popular art designs. The results of this study were as follows. First, from the result of analyzing the art design shown in product, casual, romantic, modern, dynamic and gorgeous images were. Second, art design shown in fashion, casual, romantic, chic, dynamic and gorgeous images were. Third, in wine party, romantic, elegant, gorgeous and formal images were in order and in club party, casual, gorgeous, chic and romantic images were in order. Fourth, the study displayed design by connecting aesthetic factor of artistic design to 2 wine party-wear of romantic and gorgeous images and 3 club party dresses of casual, gorgeous and chic images.

• 한국환경과학회지
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• 제19권1호
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• pp.69-80
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• 2010

Today's fundamental purpose of environmental education is to fulfill people's desire of living in a pleasant environment and at the same time promoting individualistic and collective environmentally friendly behaviors. In order to achieve these purposes, it is very important that each person holds an environmentally friendly mind that constantly tries to preserve and protect the environment which should be acquired through experiencing the importance of the environment. In order to increases the sense of attachment of people and the natural environment, the direction of environmental education should carry out education on environment related knowledge and the condition of environment damage side by side. The direction of environmental education should consider the cultivating student's awareness for active participation on matters related to the environment and to change their behaviors towards the environment. This study has tested the effect of reflective writing activities about the environment on the environmental sensitivity and willingness to act of 5th grade primary school students. For the sole purpose of this study, 70 students out of 141 5th graders of M Primary School were divided as the experimental group, and another 71 students were divided as the control group. The experimental group participated in 10 activities in where they were asked to express their thoughts and feelings in writing regarding 10 environmental problems occurring near the M Primary School. The control group participated in 10 environmental education lectures focusing on the lecturer. The results were as following. First, the reflective writing activities about the environment were effective in the environmental sensitivity of primary school students. Second, the reflective writing activities about the environment can affect the environmental willingness to act of primary school students. Third, there was a statistically significant correlation between environmental sensitivity and environmental willingness to act.

• 대한기계학회논문집A
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• 제24권1호
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• pp.215-224
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• 2000

In order to reduce the variation effects of uncertainties in the engineering environments, new robust optimization method, which considers the uncertainties in design process, is proposed. Both design variables and system parameters are considered as random variables about their nominal values. To ensure the robustness of performance function, a new objective is set to minimize the variance of that function. Constraint variations are handled by introducing probability constraints. Probability constraints are solved by the advanced first order second moment (AFOSM) method based on the reliability theory. The proposed robust optimization method has an advantage that the second derivatives of the constraints are not required. The suggested method is examined by solving three examples and the results are compared with those for deterministic case and those available in literature.

• 수산경영론집
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• 제29권2호
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• pp.199-216
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• 1998

An economic appraisal of a proposed marine ranching project is analysed using capital budgeting model such as net present value(NPV) and internal rate of return( IRR) as well as sensitivity analysis and goal seeking model. Of the factors for economic appraisal, direct benefits are to be determined by estimated harvest, prices and costs incurred by catching fishes, and indirect benefits include the additional economic effect of recreational fishing. And judging the worth of these project options depends upon the choice of discount rate of which 8.5% is recommended here. On the basis of estimated production, prices and costs the project is expected to yield NPV=615 million won and IRR=8.8%, which is quite accepted for an economic feasibility, under the first scenario, and NPV= -127 million won and IRR=7.93%, which is rejected, under the second scenario. Sensitivity analysis has been performed by calculating the switching value and sensitivity indicator in respect of the main project parameters. The results suggest that the project NPV and IRR are especially sensitive to fishes(rock fish and other rock fish) prices and fixed costs. Finally goal seeking analysis is carried out in order to reach a desired level of performance like NPV=0 in respect of the amount of hatchery-reared juverniles, the prices and the discount rate.

• 복식
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• 제52권5호
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• pp.1-13
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• 2002

The purposes of this study are to examine the relation between twenties women consumer's fashion-color reception and clothing purchase behaviors, and to propose the most effective plans of color-marketing. A questionnaire survey examined 384 persons' opinions in total. First, consumers are classified into 3 groups. according to their preferring colors and the degrees of their concerning : 'type of leading fashion-color', 'type of following fashion-color', and 'type of being indifferent to fashion-color'. Second, this study analyzed the factors of consumers' clothes-purchasing motives. : all consumer groups showed their purchasing motives in the order of 'aesthetic sense'-pursuit factor. 'sensitivity'-pursuit factor, and 'actual profit and sociality'-pursuit factor. Third, the types of consumers' purchasing clothes were divided into 2 groups: type of planned buying. And type of unplanned buying. And the relations between the above 2 groups and purchasing motives were investigated, as a result. it was proved that the consumers who have the purchasing motives of 'sensitivity'-pursuit and 'actual profit and sociality'-pursuit conducted 'planned buying'. Fourth. the relations between motive of clothing purchase and the type of purchase behavior were examined by consumer group : in the consumer group of leading fashion-color, the more did they have the purchasing motives of 'sensitivity'-pursuit or 'actual profit and sociality'-pursuit, the more did they conduct' planned buying'. In the fashion-color following group, the more did they have the purchasing motives of 'sensitivity'-pursuit or 'actual profit and sociality'-pursuit, the more did they conduct 'unplanned buying'.

• 대한기계학회논문집A
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• 제29권8호
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• pp.1102-1108
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• 2005

The integrity of nuclear piping systems has to be maintained sufficiently all the times during operation. In order to maintain the integrity, reliable assessment procedures including fracture mechanics analysis, etc, are required. Up to now, the integrity assessment has been performed using conventional deterministic approach even though there are lots of uncertainties to hinder a rational evaluation. In this respect, probabilistic approach is considered as an appropriate method for piping system evaluation. The objectives of this paper are to develop a probabilistic assessment program using reliability index and simulation technique and to estimate the damage probability of wall-thinned pipes in secondary systems. The probabilistic assessment program consists of three evaluation modules which are first order reliability method, second order reliability method and Monte Carlo simulation method. The developed program has been applied to evaluate damage probabilities of wall-thinned pipes subjected to internal pressure, global bending moment and combined loading. The sensitivity analysis results as well as prototypal evaluation results showed a promising applicability of the probabilistic integrity assessment program.

• 한국구조물진단유지관리공학회 논문집
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• 제6권1호
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• pp.131-140
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• 2002

In this paper, a limit state model based on the analysis of structural behavior of segmental prestressed concrete box girder bridges and reliability-based safety assessment method are proposed for the bridges erected by free cantilever method. Strength limit state models for prestressed concrete box girder and rigid-frame type columns are developed for a structural safety assessment during construction. Based on the proposed limit state models, the reliability of the bridge is evaluated by using the Advanced First Order Second Moment method. The proposed model and method are applied to the Seo-Hae Grand Bridge built by FCM in order to verify its effectiveness in the safety assessment during construction of the kind of bridges. The sensitivity analyses of the main parameters are also performed in order to identify the important factors that need to be controlled for the safety of the bridges during construction.

• 한국의류학회지
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• 제40권6호
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• pp.967-978
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• 2016

This study examines consumers' multi-channel choices in the search phase and purchasing phase stage according to price sensitivity and product characteristics in order to propose a multichannel strategy. For the research, one-way ANOVA, t-test, clustering analysis, and crosstabs are used for the descriptive analysis of 317 surveys on men and women conducted in 2014. The findings are as follows. First, consumers that both experience goods and search goods rely on surrounding advice as well as a search channel regardless of price sensitivity. Second, channel selection differs by price sensitivity when it comes to purchasing phase. Consumers with high price sensitivity tend to purchase from online channels; however, consumers with low price sensitivity tend to purchase from off line channels in cases of search goods. Meanwhile, cases of experience goods have no meaningful result. Third, consumers are divided into 3 groups by the tendency of channel selection. In case of experience goods, search channel choice is aligned with purchasing channel; however, search channel choice is not aligned with purchasing channel in search goods. This study provides clear information on fashion consumers' behavior on multi-channel choices compared to ones for search goods consumers on strategic strategies for fashion companies.