• 한국환경생태학회지
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• 제22권2호
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• pp.184-191
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• 2008

어류개체군에 대한 탁수의 영향을 파악하고자, 2004년부터 2005년까지 탁수하천(대기, 자운천)과 비탁수하천(봉산천, 계방천)에 분포하는 금강모치 개체군의 체장-체중 관계와 비만도지수의 변화를 알아보았다. 탁수하천과 비탁수하천간의 금강모치 평균전장을 비교해본 결과, 유의한 차이가 없는 것으로 나타났다. 남한강에서 체장-체중 관계에 따른 회귀계수 b값은 봉산천에서 3.21, 그리고 대기천에서 3.07로 나타났다. 이에 반하여, 북한강에 위치한 탁수하천의 회귀계수 b값은 비탁수하천의 값보다 약간 높았다. 그 값은 계방천에서 3.20, 자운천에서 3.23으로 각각 나타났다. 우리의 연구 결과는 금강모치 개체군 단계에서 만성 탁수의 영향이 적음을 보여준다.

• 품질경영학회지
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• 제52권2호
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• pp.201-220
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• 2024

Purpose: Smart farming is related to the low carbon certification system as it provides many opportunities to cultivate and manage crops in an eco-friendly, thereby reducing carbon footprint. However, there is a significant lack of consumer perception research on low carbon labels for smart farms vegetables. Therefore, this study aims to investigate consumer perceptions of smart farm vegetable and low carbon labels. Methods: This study manipulated cultivation type(general vs. smart farm) and low carbon labels (yes vs. no) as experimental stimuli. Measurement questions and the research model were validated through confirmatory factor analysis and reliability analysis. Hypotheses testing were conducted using SPSS 29.0, AMOS 28.0. Results: The results of the study showed no significant difference in consumers perceived naturalness based on cultivation types, and there was also no moderating effect of the low carbon label. There was no difference between environmental benefits and health benefits according to the cultivation type. Perceived naturalness had a significant effect on both environmental and health benefits, and environmental benefits showed a higher impact relationship. These benefits positively affected attitudes and willingness to pay a premium, Environmental benefits had a higher impact on attitudes, while health benefits had a higher impact on willingness to pay a premium. Lastly, attitudes were found to have a significant impact on the willingness to pay a premium. Conclusion: This study is valuable in that it investigated consumer perceptions of smart farms and low carbon labels that have not been previously studied. It compares the environmental and health benefits, confirming their influence on attitudes and willingness to pay a premium. The results suggest a potential expansion in academic research on smart farming and low carbon labels, offering practical insights for marketing strategies and policies for relevant companies.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권2호
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• pp.227-243
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• 2015

In this paper, the effects of nonlinear soft clay on dynamic embedment of offshore pipeline were investigated. Seabed embedment by pipe-soil interactions has impacts on the structural boundary conditions for various subsea structures such as pipeline, riser, pile, and many other systems. A number of studies have been performed to estimate real soil behavior, but their estimation of seabed embedment has not been fully identified and there are still many uncertainties. In this regards, comparison of embedment between field survey and existing empirical models has been performed to identify uncertainties and investigate the effect of nonlinear soil parameter on dynamic embedment. From the comparison, it is found that the dynamic embedment with installation effects based on nonlinear soil model have an influence on seabed embedment. Therefore, the pipe embedment under dynamic condition by nonlinear parameters of soil models was investigated by Dynamic Embedment Factor (DEF) concept, which is defined as the ratio of the dynamic and static embedment of pipeline, in order to overcome the gap between field embedment and currently used empirical and numerical formula. Although DEF through various researches is suggested, its range is too wide and it does not consider dynamic laying effect. It is difficult to find critical parameters that are affecting to the embedment result. Therefore, the study on dynamic embedment factor by soft clay parameters of nonlinear soil model was conducted and the sensitivity analyses about parameters of nonlinear soil model were performed as well. The tendency on dynamic embedment factor was found by conducting numerical analyses using OrcaFlex software. It is found that DEF was influenced by shear strength gradient than other factors. The obtained results will be useful to understand the pipe embedment on soft clay seabed for applying offshore pipeline designs such as on-bottom stability and free span analyses.

• 한국조경학회지
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• 제43권1호
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• pp.54-68
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• 2015

본 연구는 근린공원에 대한 이용자의 공원지각환경이 건강증진인식에 미치는 영향을 분석하기 위해 경상남도 창원시의 8개 근린공원을 대상으로 공원별 현장조사 및 설문조사를 실시하였다. 연구결과에 따르면, 먼저 공원별 공원지각환경에서는 대부분의 공원이 집에서 공원까지의 거리와 집에서 공원까지의 길 환경이 높게 평가된 반면, 수공간과 공원 내 다양한 볼거리는 충분하지 못한 것으로 분석되었다. 다음으로 23개의 지각환경 변수들을 요인분석한 결과, 경관성, 안락성, 접근성, 활동성, 편의성, 쾌적성의 6개 요인으로 분류되었다. 이를 토대로 건강증진인식과 지각환경요인과의 관련성을 분석한 결과, 8개 공원 중 4개 공원에서 지각환경요인이 신체적 건강증진인식에 유의한 영향을 주는 것으로 나타났다. 특히, 접근성과 활동성이 3개의 공원에서 영향력이 있는 변수로 분석되었다. 또한, 심리적 건강증진인식의 경우, 8개 공원 중 5개 공원에서 유의한 영향을 주는 것으로 나타났으며, 접근성이 4개의 공원에서 영향력이 있는 변수로 평가되었다. 이상과 같은 결과들은 기존의 공원 환경을 개선하고, 새로운 공원을 조성하고자 할 때 효율적인 기초자료로 활용될 수 있을 것으로 판단된다.

• Steel and Composite Structures
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• 제28권2호
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• pp.209-221
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• 2018

An empirical and efficient method is presented for calculating the dynamic increase factor to amplify the applied loads on the affected bays of a steel frame structure with semi-rigid connections. The nonlinear static alternate path analysis is used to evaluate the dynamic responses. First, the polynomial models of the extended end plate and the top and seat connection are modified, and the proposed polynomial model of the flush end plate connection shows good agreement as compared with experimental results. Next, a beam model with nonlinear spring elements and plastic hinges is utilized to incorporate the combined effect of connection flexibility and material nonlinearity. A new step-by-step analysis procedure is established to obtain quickly the dynamic increase factor based on a combination of the pushdown analysis and nonlinear dynamic analysis. Finally, the modified dynamic increase factor equation, defined as a function of the maximum ratio value of energy demand to energy capacity of an affected beam, is derived by curve fitting data points generated by the different analysis cases with different column removal scenarios and five types of semi-rigid connections.

• 한국환경과학회지
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• 제19권8호
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• pp.1067-1076
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• 2010

How would environmental education be implemented for effectiveness today? Deep reflection on the way of teaching environment in classes to achieve effectiveness is required. If there exist differences in students' environmental perception depending on environment class pattern, its most effective way should be looked for. In environmental education, inducing the students to have advisable attitude voluntary about environment is more important than teaching them environmental knowledge. From such view, students' active participation is necessary for successful environmental classes. Students need to be set to share their principle, values, attitude about environment problems at environmental class through presentation which is important factor to make them have advisable environmental attitude. Therefore, environmental class need to be carried out student-led way. For that, a class model need to be designed which will be helpful for the students to arrange and elaborate their emitting thought about environment problems through disclosing their thoughts to share them with fellow students which will end up in their advisable environmental attitude. This study aimed to find out the effectiveness of environmental collage making class contributive to offering various environmental perception to students and grasping others' thinking about environment. Fifty-eight 10th graders at U Science High School in Ulsan metropolitan city were selected for the study that carried out from 2010 April to June by choosing total 10 environmental themes divided into environmental collage making class applied to the 30 test group students, and general environmental class applied to 28 control group students. Following are the study results. First, in students' environmental sensitivity, the students in the environmental collage making class appeared to be higher compared with them in general environmental class. Second, in students' intentional environment action, the students in the environmental collage making class appeared to be higher compared with them in general environmental class. Third, in students' satisfaction with environmental class, the students in the environmental collage making class appeared to be higher compared with them in general environmental class.

• 청정기술
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• 제9권1호
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• pp.43-48
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• 2003

As a result of study on factor affecting absorption efficiency using the structured packing, Mellapak N. 250Y for the chemical absorption of $CO_2$ that cause global warming due to development of industry, it is shown that Mellapak N. 250Y has lower pressure drop and superior efficiency of mass transfer than 25mm Pall ring. Also, in the absorption process, it produces high efficiency in the increase of load and concentration of absorption liquid and produces low efficiency in the increase of temperature. In the effect of overall mass transfer coefficient for 15% MEA on the temperature variation of absorbent, when absorbent temperature for 15% MEA varied as 25, 50, $80^{\circ}C$, overall mass transfer coefficients were shown as 0.83, 1.00, $0.90kmol/m^3-h-kPa$.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1071-1076
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• 2003

Basic creep of concrete during very early ages is an important factor on the behavior of young concrete and a great deal of research has been executed. However, in recent studies, it was revealed that the basic creep measured by sealed concrete was inaccurate, especially for high strength concrete because of autogenous shrinkage at early age. This paper presents the results from experimental study that investigate to explore the effect of autogenous shrinkage in basic creep. More specifically, four different mix proportions were casted and the primary variables were water-cement ratios. Through this research, it was found that the differences between apparent specific creep and real specific creep were remarkable in low water-cement ratio at early age. Therefore, it is recommended to modify existing creep model by considering autogenous shrinkage

• 한국정밀공학회지
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• 제22권5호
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• pp.138-143
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• 2005

Recently, automobile manufacturers regarding stability, economic environmental-friendly problems by the development of automobile, environmental problem as designing the exhaust system. Increasingly strict environmental regulations to lower fuel consumption and reduce emission. Also to reduce the noise and the vibration of the automobile. According to develop variable type muffler, dual muffler and active intelligence exhaust system unit. Improvement in engine performance and fuel consumption rate demand information of pressure fraction and heat characteristics. To be able to determine these factor for we experiment on each case of exhaust system unit. In this study, how back pressure is distributed in flow-through in exhaust system and how to design exhaust system flexibleness, efficiency and combustion charateristics influenced by back pressure. This study furnish basic data for engineers, technicians.

• Journal of Preventive Medicine and Public Health
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• 제44권1호
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• pp.41-47
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• 2011

Objectives: This study assessed the factors that have an influence on the residents exposed to heavy metals, and we utilized the findings to establish the proper management of abandoned metal mines in the future. Methods: For a total of 258 residents who lived close to abandoned mines in Gangwon-province and Gyeonggi-province, the exposure factors and biomarkers in their blood and urine were comparatively analyzed via multiple regression analysis. Results: The blood levels of lead and mercury and the cadmium levels in urine were found to be higher in the study group than that in the average Korean. For the blood levels of heavy metals according to each exposure factor, all of them were found to be significantly higher in both of the group residing for a longer period of time and the group living closer to the source of pollutants. Multiple regression analysis disclosed that all the heavy metals, except lead, in their blood were significantly reduced in proportion to the increased distance of inhabitancy from the mines. Their other biomarkers were within the normal ranges. Conclusions: We found that the distance between the residential village and the mines was a factor that affects the blood level of heavy metals in the villagers. This finding could be an important factor when developing a management model for the areas that surround abandoned metal mines. (ED note: I much like this important study.)