• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.341-346
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• 1998

Optimization for the production of Pest an was followed by the Plackett-Burman Design, using modified Czapek-dox medium as the starting point. At the flask level, $K_2HPO_4$, $MgSO_4{\cdot}7H_2O$, and aeration variables positively affected the Pestan production, DCW (dry cell weight), apparent viscosity, and flocculating activity response. KCI and $FeSO_4{\cdot}7H_2O$ negatively affected the Pestan production, DCW, apparent viscosity, and flocculating activity response. Aeration variable was shown to have a positive effect on only the flocculating activity response among Pestan production, DCW, and apparent viscosity responses. In comparison of the positive and negative variables media conditions, Pestan production and flocculating activity differed by about 9 and 125 times, respectively. In particular, at the jar fermentor level, the aeration variable was the most important factor of the all responses (pestan production, DCW, apparent viscosity, flocculating activity, and anionic charge density). The flocculating activity and apparent viscosity of Pestan were closely related to the molecular chain length and charge density.

• 자원ㆍ환경경제연구
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• 제26권4호
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• pp.473-498
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• 2017

본 연구는 Porter 가설을 기반으로 내생성을 고려한 환경규제가 한국 제조업의 생산성에 미치는 영향을 2003년부터 2013년까지의 "광업 제조업조사", "과학기술통계" 및 "환경통계 포털" 자료를 이용하고 패널고정효과 모형을 사용하여 분석했다. 기존 연구들에서 발생할 수 있는 내생성 중 누락변수편의를 없애기 위해 시장경쟁정도, 산업별 R&D 투자금액, 시장개방도 및 진입 퇴출율과 같이 생산성에 영향을 미치는 요인들을 설명변수로 포함하여 분석했으며, 측정오차 및 역인과성을 제거하기 위해서 도구변수 추정법을 이용했다. 주요 분석결과는 다음과 같다. 첫째, 환경규제는 장기적으로 한국 제조업의 생산성을 개선시켜 Porter 가설을 지지하는 것으로 나타났다. 둘째, 누락변수에 의한 내생성은 분석결과에 큰 영향을 미치지 않았으나 측정 오차 및 역인과성에 의한 내생성은 환경규제의 효과를 과소평가 시키는 것으로 분석되었다. 마지막으로 환경기술 R&D은 단기적으로 생산성을 감소시켰다.

• Journal of Biosystems Engineering
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• 제43권4호
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• pp.342-351
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• 2018

Purpose: Recently, an increasing number of farms have been cultivating shiitake mushrooms using a sawdust substrate and a cooler/heater. In this study, an attempt was made to develop an environmental control system using a heat pump for cultivating high-quality shiitake mushrooms. Methods: An environmental control system, consisting of an air-to-water type heat pump, a thermal storage tank, and a radiator in a variable opening chamber, was designed and fabricated. The system was also installed in the cultivation facility of a farm cultivating shiitake mushrooms so as to compare the proposed control system with a conventional environmental control system using a cooler-condensing unit and an electric hot water boiler. Results: The uniformity of the environment was analyzed through environment measurements taken at several positions inside the cultivation facility. It was determined that the developed environmental control system is able to control the variations in temperature and relative humidity to within 1% and 3%, respectively. In addition, a maximum temperature difference of $30^{\circ}C$ (maximum of $35^{\circ}C$, minimum of $5^{\circ}C$) and a maximum relative humidity difference of 30% (maximum of 90%, minimum of 60%) can be attained within 30 min inside the cultivation facility through the cooling of the heat pump and heating of the radiator in a variable opening chamber. Thus, the developed control system can be used to cultivate high-quality shiitake mushrooms more effectively than a conventional cooler and heater. Conclusions: In comparison with a conventional environmental control system, the developed system decreased the yield of ordinary mushrooms by 65%, and increased that of high-quality mushrooms by 217%. This corresponds to a 16% increase in gross farm income. Consequently, the developed system is expected to improve the income of shiitake mushroom cultivating farms.

• 산업경영시스템학회지
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• 제6권9호
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• pp.111-124
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• 1983

The basic model of decision problem the enterprise is conforonted with includes the following 3 elements ; 1) Elements that can not be controlled by the decision maker : In the thesis elements are named environmental variables, and varied itself according to the change of environmental condition. 2) Elements that can be controlled by the decision maker ; These elements are called decision elements in the thesis and variable according to the event. 3) object of decision making : The degree of achievement to the object is identified by taking various criteria- The index indicating the degree of achievement to the object whatever criterion is applied is called object function in the thesis. It's the fanetion of environmental variable, decision variable and object function. The relation between them brings forth the relation formula that characterize the each problem. The basic types of decision making model use in the thesis are as following ; 1) The problem of decision making under conditions of certainty. 2) The problem of decision making under conditions of risk. 3) The problem of decision making under conditions of uncertainty. 4) The problem of decision making under competitive condition. in general case that the Profit of two decision makers varies, what we regard the decision that make the sum of profit of two men maximum as the best choice for two men has a reasonability in certain case. When the sum of profit two men is zero, by taking toe promise that ail of them art according to the min-max criteria and by extending the object of choice to the mixed strategy. We certify the existance of equilibrium solution and admit them as the best solution of competitive model in general.

• 한국환경과학회지
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• 제24권3호
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• pp.329-337
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• 2015

The purpose of this study was to observe the influence adolescents' environmental experience and environmental consciousness have on the pro-environmental consumption behavior. Also by examining the variable relation, the study scoped out the effectiveness of environmental experience. For the analysis, high school students in Korea were gathered from online and the correlation analysis, multiple regression analysis, and Baron and Kenny mediation analysis were conducted among a total of 521 surveys. The main findings are as follows: First, adolescents' environmental experience, environmental consciousness and pro-environmental consumption behavior showed a positive relationship. In other words, the more the experience, the more sense of responsibility adolescents had towards the environment and society, leading them to have pro-environmental consumption behavior. Second, environmental experience and environmental consciousness were proven to be essential factors that have influence on the adolescents' pro-environmental consumption behavior. Third, partial mediating effect of environmental consciousness was verified in accordance with the relationship between environmental experience and pro-environmental consumption behaviour. The findings suggest the importance of adolescents' environmental consciousness and improvement of pro-environmental consumption behavior by having students gain environmental experience.

• Earthquakes and Structures
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• 제1권1호
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• pp.43-67
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• 2010

A gradient-based evolutionary optimization methodology is presented for finding the optimal design of both the added dampers and their supporting members to minimize an objective function of a linear multi-storey structure subjected to the critical ground acceleration. The objective function is taken as the sum of the stochastic interstorey drifts. A frequency-dependent viscoelastic damper and the supporting member are treated as a vibration control device. Due to the added stiffness by the supplemental viscoelastic damper, the variable critical excitation needs to be updated simultaneously within the evolutionary phase of the optimal damper placement. Two different models of the entire damper unit are investigated. The first model is a detailed model referred to as "the 3N model" where the relative displacement in each component (i.e., the spring and the dashpot) of the damper unit is defined. The second model is a simpler model referred to as "the N model" where the entire damper unit is converted into an equivalent frequency-dependent Kelvin-Voigt model. Numerical analyses for 3 and 10-storey building models are conducted to investigate the characters of the optimal design using these models and to examine the validity of the proposed technique.

• International Journal of Concrete Structures and Materials
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• 제19권1E호
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• pp.11-16
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• 2007

Recently, probabilistic neural network (PNN) has been proposed to predict the compressive strength of concrete for the known effect of improvement on PNN by the iteration method. However, an empirical method has been incorporated in the PNN technique to specify its smoothing parameter, which causes significant uncertainty in predicting the compressive strength of concrete. In this study, a modified probabilistic neural network (MPNN) approach is hence proposed. The global probability density function (PDF) of variables is reflected by summing the heterogeneous local PDFs which are automatically determined by the individual standard deviation of each variable. The proposed MPNN is applied to predict the compressive strength of concrete using actual test data from a concrete company. The estimated results of MPNN are compared with those of the conventional PNN. MPNN showed better results than the conventional PNN in predicting the compressive strength of concrete and provided promising results for the probabilistic approach to predict the concrete strength by using the individual standard deviation of a variable.

• 한국의류산업학회지
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• 제14권3호
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• pp.430-437
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• 2012

This study analyzed the sensibility of eco-friendly fabrics for college students and investigated their attitude on environmental problems, trust reliability onto eco-apparel products, and their purchase state. We tested 6 eco-friendly fabrics (recycled polyester, organic cotton, green tea, charcoal, bamboo, and nettle) through a survey using the Likert scale of 12 polar sensibility words. Most fabrics showed feelings that were smooth, natural, female, and country these were followed by fashion, cheap, functional, sustainable, warm, and vintage. In addition, nettle fabric showed 'rough' feeling, and recycled polyester fabric showed an 'artificial' feeling. Correspondence analysis showed the distance and direction between fabric types and sensibility words with a 2D diagram where the X axis was named with 'Soft <-> Hard' and Y axis was with 'Environmental <-> Manmade' to represent the relationship between fabric types and the sensibility words. According to the results of the multiple regression analysis, the cognition level of the consumer for environmental problems was found to be the most influential variable on the loyalty purchase of eco-friendly products; however, the trust reliability level of consumer onto eco-friendly apparel products was found to be the most influential variable on the conditional purchase of eco-friendly apparel products.

• The Journal of Asian Finance, Economics and Business
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• 제9권8호
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• pp.57-69
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• 2022

The purpose of the study is to empirically investigate the effect of suppliers' environmental consciousness on environmental information sharing and management performance and to conduct the mediating effect of environmental information sharing between the environmental consciousness of suppliers and environmental management performance. The scope of environmental consciousness was extended from the consumer perspective to the organizational perspective and proposed a variable called environmental information sharing to explain how environmental consciousness affects environmental management performance. The research model and hypotheses were established based on previous studies. After collecting 295 samples of effective responses from suppliers, an empirical analysis was conducted using structural equation modeling. The findings show that suppliers' environmental consciousness affects environmental information sharing and management performance, and such sharing has a mediating effect on the relationship between suppliers' environmental consciousness and environmental management performance. The fact that environmental consciousness affects environmental management performance indicates that environmental consciousness is not just a concept of values such as the firm's belief or will, but a part of the firm's actual goal of performance. Therefore, suppliers have difficulties in reality such as a lack of professional manpower or guideline, but it is necessary to enhance the importance of environmental consciousness and promote environmental information sharing.

• 대한교통학회지
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• 제26권4호
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• pp.111-121
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• 2008

효과적인 가변제한속도(Variable Speed Limit: VSL)는 교통사고를 예방하고 교통정체를 완화시키는데 기여하는 중요한 교통류 제어방안이다. 본 연구에서는 교통사고 예방을 목적으로 가변제한속도를 적용하는 방법론을 제시하였다. 가변제한속도를 적용하는 조건을 두 가지로 분류하였는데, 사고위험도 예측모형에 따른 제한속도 변화와 도로환경조건의 변화에 따른 제한속도 조정 방안을 제안하였다. 예측된 사고위험도에 따른 가변제한속도의 적용은 검지기에서 추출되는 교통량, 속도, 점유율자료와 교통사고자료로 이항로지스틱회귀분석 기법을 사용하여 구축된 사고위험도 예측모형을 사용하였다. 한편, 도로환경조건에 따른 가변제한속도 적용에서는 안개, 폭우, 폭설로 인한 시거제약 상황과 결빙, 비, 눈으로 인한 노면마찰력감소상황 시 최소정지거리 계산을 통해 각 상황에 적용되어야 하는 제한속도를 제시하였다. 이를 바탕으로 통합도로환경조건 모니터링 시스템 하에서 사고위험도와 도로환경조건을 관측하고 제한속도를 변화시키는 가변제한속도 시스템 알고리즘을 제시하였으며, 제안된 알고리즘의 현장 적용 시 고려되어야 할 기술적 이슈를 논의하였다.