• Transactions of the Korean hydrogen and new energy society
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• v.33 no.4
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• pp.419-429
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• 2022

Effects of operating variables on temperature profile and performance of 3 MWth chemical looping combustion system were estimated by mass and energy balance analysis based on configuration and dimension of the system determined by design tool. Air reactor gas velocity, fuel reactor gas velocity, solid circulation rate, and solid input percentage to fluidized bed heat exchanger were considered as representative operating variables. Overall heat output and oxygen concentration in the exhaust gas from the air reactor increased but temperature difference decreased as air reactor gas velocity increased. Overall heat output, required solid circulation rate, and temperature difference increased as fuel reactor gas velocity increased. However, overall heat output and temperature difference decreased as solid circulation rate increased. Temperature difference decreased as solid circulation rate through the fluidized bed heat exchanger increased. Effect of each variables on temperature profile and performance can be determined and these results will be helpful to determine operating range of each variable.

• The Journal of Industrial Distribution & Business
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• v.11 no.3
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• pp.39-50
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• 2020

Purpose: Agriculture, which is heavily influenced by climate conditions, is one of the industries most affected by climate change. In this respect, various studies on the impact of climate change on the agricultural market have been conducted. Since climate change is a long-term phenomenon for more than a decade, long-term projections of agricultural prices as well as climate variables are needed to properly analyze the impact of climate change on the agricultural market. However, these long-term price projections are often major constraints on studies of climate changes. The purpose of this study is to analyze the impacts of climate changes on the Korean onion market using ex-post analysis approach in order to avoid the difficulties of long-term price projections. Research design, data and methodology: This study develops an annual dynamic partial equilibrium model of Korean onion market. The behavioral equations of the model were estimated by OLS based on the annual data from 1988 to 2018. The modelling system is first simulated to have actual onion market conditions from 2014 to 2018 as a baseline and then compared it to the scenario assuming the climatic conditions under RCP8.5 over the same period. Scenario analyses were simulated by both comparative static and dynamic approach to evaluate the differences between the two approaches. Results: According to the empirical results, if the climate conditions under RCP8.5 were applied from 2014 to 2018, the yield of onion would increase by about 4%, and the price of onion would decrease from 3.7% to 17.4%. In addition, the average price fluctuation rate over the five years under RCP8.5 climate conditions is 56%, which is more volatile than 46% under actual climate conditions. Empirical results also show that the price decreases have been alleviated in dynamic model compared with comparative static model. Conclusions: Empirical results show that climate change is expected to increase onion yields and reduce onion prices. Therefore, the appropriate countermeasures against climate change in Korean onion market should be found in the stabilization of supply and demand for price stabilization rather than technical aspects such as the development of new varieties to increase productivity.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.1
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• pp.71-90
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• 2017

The purpose of this study is to identify the characteristics of currently targeted consumers of the fashion enterprises. It also aims to assess the value of consumer-related variables that are related to market segmentation. In order to identify the characteristics of targeted consumers, the contents of brand concept and target of 143 brands for women's clothing, and 79 brands for men's clothing were qualitatively analyzed. The results are as follows. First, the demographic characteristics of both male and female included the desire to appear younger, and be more youthful in sensibilities than their actual age. In terms of occupation, male had more variety and concreteness than female. Male and female were above middle class, with an emphasis on being a part of the new generation, one that is young, free, healthy, and leisurely. Second, the psychological and behavioral characteristics of both male and female consumers included the benefit sought of the following: rationality, economy, practicality, functionality, individuality, fashionability, and aesthetics. Their fashion orientations were found to be practical, rational, fashionable, expressive of individual style, and aesthetic sensibilities. Their lifestyles were characterized by elements such as rationality, smartness, urban, active, healthy, young, leisurely, and stable. In terms of the spirit, female had a tendency to be intelligent, elegant, and sensitive, while also being self-reliant, self-disciplined, and unafraid of challenging situations. The male consumers had a tendency to be rational, progressive, passionate, and embracing change, with emphasis on legitimacy, honor, success, pride, and affluence. Third, the usefulness of consumer-related variables in targeting consumers was different according to male and female. These results show that there is a need for these variables to be looked at more closely during market segmentation process. This research may be used as base material in setting up the brand concept and the target market.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.111-119
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• 2001

This study aims both to analyze view resources of on agricultural village and its original view image in order to establish indexation and the direction of development and to present assessment model of agricultural view for expectations in plan change for and improvement of agricultural view and alternative valuation. To do this, I selected four agricultural villages as the case areas for this study and examined view resources and their residents' consciousness through a questionnaire and investigated the image preference degree of agricultural village view and view preference. The results of this study are as follows: 1. The newly-introduced artificial view elements, according to development, are a hindrance element of agricultural view; as such Commercial buildings and transmission towers show the highest frequency and are increasing. The problem is that development is being made without any systematic plan. 2. In the examination of images of agricultural villages, the traditional ones are 2.82 on average, which means the view is modern; the natural ones are 3.3 on average, which indicates natural images; the agricultural ones are 3.67 on average, which emerge as agricultural images. View preference degree is 3.34 on average, which is usually good. 3. It is proved that all of the variables of type of location form and view image increase the degree of view preference; size in causal relation can be identified by parameter estimate; that Type I. image variables of agricultural-ness contribute to the dependent variables, view preference degree. 4. It is identified that view preference degree according to location from emerges mountain type, champaign type, and suburbs type in order of preference.

• Journal of Families and Better Life
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• v.26 no.6
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• pp.159-166
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• 2008

According to the change in diverse tendency of residents, construction companies has developed the brands of apartments with the concepts of LOHAS, well-being, ubiquitous, etc. The purpose of this study was to suggest space requirement and planning for residents characteristics. The questionnaire survey was adopted in this study and 252 cases were used for data analysis. The survey analysis has been made by using of SPSS WIN 12.0. The major findings were as follows; (1) Resident opinion about the direction of each space was investigated into the need of South-facing in master bedroom highly. (2) The residents didn't want to decrease the current size of each space, the space which wanted to increase was livingroom. (3) The significant variables of space requirement and planning for residents characteristics were family life cycle, the age of householder, the occupation of householder, the size of apartment.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.854-855
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• 2011

In this paper, Interior permanent magnet synchronous motor(IPMSM) with concentrated winding for 110cc electric motorcycle is introduced. Optimum design is performed so as to satisfy wide speed operation range. And output characteristics is analyzed according to shoe height in many variables. Because partial magnetic saturation in shoe affects the harmonics, output characteristics of motor could be confirmed that a significant change. As a result, the new shape and the optimal design parameters considering the partial magnetic saturation is obtained. Compared with the base model, wide operating range was confirmed.

• 한국가스학회:학술대회논문집
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• 2004.11a
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• pp.82-87
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• 2004

Compression ring is a part of LNG storage tank. The main function of the compression ring is connected the roof plate with concrete side wall. End of its one side is embedded in the side concrete wall and the other's connected with the roof plate by welding. It is designed to support stably for all the loads such as self weight of steel roof, inner pressure and concrete weight. We fulfill the FEM analysis to analysis the compression ring behavior during construction. Also we studied the effect of the change of design variables. On the basis of the results, we could introduce a more reasonable design method for compression ring.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.05a
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• pp.412-414
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• 2005

In this paper, we present a method of fuzzy controller design for the power plant superheater in the form of bilinear system. For the steam temperature control, the input variables are constructed by the area of difference between the profiles estimated from bilinear observer and reference profiles, and the time rate of change. We estimate the control rules by T. Takagi and M. Sugeno's fuzzy model. The feasibilities of the suggested method are illustrated via the computer simulation result.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.75.1-75
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• 2001

In this paper, we provide the synthesis of non-fragile H$\infty$ output feedback controllers for linear systems with affine parameter uncertainties, and dynamic output feedback controller with structural uncertainty. The sufficient condition of controller existence, the design method of robust and non-fragile H$\infty$ output feedback controller, and the region of controllers which satisfies non-fragility are presented. Also using some change of variables and Schur complements, the obtained condition to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed ...

• International Journal of Control, Automation, and Systems
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• v.1 no.4
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• pp.503-510
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• 2003

This paper describes the synthesis of robust and non-fragile $H^{i~}$state feedback controllers for linear varying systems with time delay and affine parameter uncertainties, as well as static state feedback controller with structural uncertainty. The sufficient condition of controller existence, the design method of robust and non-fragile $H^{i~}$static state feedback controller, and the region of controllers satisfying non-fragility are presented. Also, using some change of variables and Schur complements, the obtained conditions can be rewritten as parameterized Linear Matrix Inequalities (PLMIs), that is, LMIs whose coefficients are functions of a parameter confined to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed loop system in spite of time delay and controller gain variations within a resulted polytopic region.