• The Korean Journal of Ecology
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• 제18권4호
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• pp.451-462
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• 1995

A comparative study on the minimal areas and the community structures in pine IPinus densiflora) and oak (Quercus mongolica) frests was carried out. Basic tools used in the present study were species diversity and classical ayntaxonomy (Z.-M. School) of the phytocoenosis. Total 120 nest-quadrats in 40 stands situated at the syngeographical region of the Lindero-Quercion mongolicae were investigated. Each stand was classified on the basis of species combination, and species abundance was computed with net contribution degree (NCD). Composition ratio of plant-from and rate of actual species diversity (ASD) to syntaxa were computed for better interpretation of the minimal areas. Four syntaxa were structured: Saso-Quercetum mongolicae, Viola albida-Quercus mongolica community, Carex hummilis-Pinus densiflora community and Juniperus rigida-Pinus densiflora community. Their minimal areas were determined as 305, 196, 169, and 81 ㎡, respectively. Aconsistent regularity between species composition ratio and community structure in the multi-layered plant community was hardly found. The minimal areas increased linearly with increasing rate of ASD, and a phytocoenosis developed by diverse arboreta in the understory and shrub-layer should be investigated with larger sampling sizes.

• 한국초등과학교육학회지:초등과학교육
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• 제30권4호
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• pp.562-573
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• 2011

The purpose of this study was to examine the effects of teaching-learning programs from the perspective of brain-based learning science. Four units in 5th grade elementary science programs of the Revised 2007 National Curriculum were selected as contents to study. As the brain-based learning science analysis method, equations of the brain compatibleness index (BCI) and contribution degree on the brain compatibleness index (BCICRE) were applied to them. This study showed that there were qualitative and quantitative differences among the analyzed teaching-learning programs through the unit and curriculum. The results showed that hands-on activities like experiments or open inquiry activities improved their evaluation of the teaching-learning programs. From the analyzing, teachers can judge whether each teaching-learning program made considered the brain of the learners. Furthermore, this study can provide useful information to consult of various science teaching-learning programs brain-based learning.

• 한국경영과학회지
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• 제40권4호
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• pp.1-18
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• 2015

This paper proposes relational capability as a main driver of constructing inter-organizational collaboration networks. Based on social network theory and relational view literature, three components of relational capability are constructed and implemented by an agent-based model. The components include organizational capability, structural capability, and trust between a partner and a focal firm. These three components are updated by two micro mechanisms: structural mechanism and relational mechanism. Structural mechanism is a feedback loop in which the relational capability increases structural capability and vice versa. Relational mechanism is a learning-by-doing process in which a focal firm experiences success or failure of collaboration and the experience increases or decreases cumulative trust in a partner firm. Result of agent-based simulation shows that a collaboration network emerges through interactions of firm's relational capabilities and the characteristics of emerged networks vary with the contribution of structural capability and trust to relational capability. Specifically, in case structural capability contributes more to relational capability, the average degree centrality and collaboration proportion increases as time passes and enters into an equilibrium state. In that case, almost every firms participated in the network collaborates each other so that the emerged network becomes highly cohesive. In case trust contributes more to relational capability, the results are reversed. In an equilibrium state, the balance of contribution between structural capability and trust makes an emerged network larger and maximizes average degree centrality of the network.

• 한국경영과학회지
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• 제28권4호
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• pp.155-189
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• 2003

In this research, the comprehensive evaluation model of IS(information systems) for public sectors is theoretically constructed through reviewing and integrating previous IS evaluation-related research. This model is hypothesized to consist of five sectors(System Sector, User Sector, Organization and Management Sector, Resource Management Sector and Strategic Contribution Sector), ten evaluation items belonging to these five evaluation sectors, and sixty two evaluation indices for these ten evaluation items. The results of empirical analyses to test the validity of the research model show that the evaluation sectors turn out to be the same ones as proposed in the hypothetical model. The evaluation items(System Quality, Information Quality, Service Quality) in System Sector proves to be consistent with the hypothetical model. However, in case of User Sector, two evaluation items(Perceived Usefulness and User Satisfaction) which are included in the hypothetical model are found to be merged into one item(User Satisfaction). And, it is shown that four evaluation items such as the Efficiency of Internal Process, Customer Satisfaction, Organizational Innovation, and the Degree of Informatization competence improvement are included in Organization and Management Sector, differently from the research model in which the items, Organizational innovation and the Degree of Informatization competence improvement, are not divided. As a final result, sixty two evaluation indices that comprise all the evaluation items belonging to five sectors are found to be reduced to fifty seven ones through factor analyses, criterion-related validity tests and reliability analyses.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1576-1584
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• 2008

In this study, canonical correlation analysis (CCA) was applied to estimate the relationship between three different sexual maturity traits (X set: days to first egg (DFE), weight of the first egg (WFE), body weight at first egg (BWFE)) and level of nutrient intake (Y set: energy (EI) and protein intake (PI)) or the egg production traits at two different periods (Z set: number of egg (NE1 and NET) and weight of egg (WE1 and WET) from 22 to 25 (Wfirst) and 22 to 33 wk of age (Wall), respectively), which were measured from 64 egg-type pullets (Isa Brown) manipulated for time of access to energy and protein sources to onset of egg production. Partial CCA (PCCA) was used to eliminate the contribution of differences in the levels of nutrient intake to canonical variables for X and Z sets at the first production period. Estimated canonical correlation coefficients between X set and Y set (0.429, p = 0.042), X set and Z set (0.390, p = 0.007 for Wfirst) and within Z set (between Wfirst and Wall; 0.780, p<0.001), and partial canonical correlation coefficient between X set and Z set (0.415, p = 0.009) were significant. Canonical weights and loadings from CCA indicated that the BWFE had the largest contribution compared to the DFE and WFE to variation of egg number produced at two different periods. The results from PCCA indicated that the contribution of PI and EI to the degree of the correlation between canonical variables for X and Z sets were unfavourable. In conclusion, the effect of body weight at sexual maturity upon the availability of nutrients can have a higher contribution to variation of egg production in pullets if the contribution of differences in nutrient intakes to onset of egg production were eliminated.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.13-14
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• 2014

Ultra high performance concrete (UHPC) consists of cement, silica fume (SF), sand, fibers, water and superplasticizer. Typical water/binder-ratios are 0.15-0.20 with 20-30% of silica fume. The development off properties of hardening UHPC relates with both hydration of cement and pozzolanic reaction of silicafume. In this paper, by considering the production of calcium hydroxide in cement hydration and its consumption in the pozzolanic reaction, a numerical model is proposed to simulate the hydration of UHPC. The degree of hydration of cement and degree of reaction of silica fume are obtained as accompanied results from the proposed hydration model. The properties of hardening UHPC, such as degree of hydration of cement, calcium hydroxide contents, and compressive strength, are predicted from the contribution of cement hydration and pozzolanic reaction. The proposed model is verified through experimental data on concrete with different water-to-binder ratios and silica fume substitution ratios.

• Journal of Information Science Theory and Practice
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• 제7권3호
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• pp.31-39
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• 2019

Nowadays, recommender systems suggest lists of items to users considering not only accuracy but also diversity and novelty. However, suggesting the most diverse list of items to all users is not always acceptable, since different users prefer and/or tolerate different degree of diversity. Hence suggesting a personalized list with a diversity degree considering each user preference would improve the efficiency of recommender systems. The main contribution and novelty of this study is to tune the diversity degree of the recommendation list based on the users' variety-seeking feature, which ultimately leads to users' satisfaction. The proposed approach considers the similarity of users' desire diversity as a new parameter in addition to the usual similarity of users in the state-of-the-art collaborative filtering algorithm. Experimental results show that the proposed approach improves the personal diversity criterion comparing to the closest method in the literature, without decreasing accuracy.

• Geomechanics and Engineering
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• 제28권1호
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• pp.35-48
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• 2022

The effect of discrete polypropylene fibre reinforcement on shear strength parameters, tensile properties and isotropic index of stabilized compacted residual subgrade was investigated. Composites of compacted subgrade were developed from polypropylene fibre dosage of 0%, 1%, 2.5% and 4% and 3% cement binder. Saturated compacted soil benefited from incremental fibre dosage, the mobilized friction coefficient increased to a maximum at 2.5% fibre dosage from 0.41 to 0.58 and the contribution due to further increase in fibre dosage was marginal. Binder stabilization increased the degree of isotropy for unreinforced soil at lower fibre dosage of 1% and then decreased with higher fibre dosage. Saturation of 3% binder stabilized soil decreased the soil friction angle and the degree of isotropy for both unstabilized and binder stabilized soil increased with fibre dosage. The maximum tensile stress of 3% binder stabilized fibre reinforced residual soil was 3-fold that of 3% binder stabilized unreinforced soil. The difference in computed and measured maximum tensile and tangential stress decreased with increase in fibre dosage and degree of stabilization and polypropylene fibre reinforced soil met local and international criteria for road construction subgrade.

• 경영정보학연구
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• 제6권2호
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• pp.113-135
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• 2004

본 연구는 조직구성원의 지식기여도를 객관적으로 측정하기 위한 평가항목 및 각 항목의 가중치를 개발하고자 하는 연구이다. 평가항목의 개발을 위해 연역적 방법과 가중치 개발을 위해 델파이 기법이 각각 사용되었다. 평가항목의 도출을 위해 우선 '지식기여'에 대하여 정의를 내리는 것으로 출발하였다. 도출된 정의를 기초로, 지식기여의 형태는 크게 형식적 기여와 암묵적 기여로 구분되었다. 형식적 기여는 기여하는 지식의 내용에 따라 사실지와 방법지로 구분되었다. 사실지는 구체적으로 방법지 산출물과 기타 사실지로, 방법지는 방법지 매뉴얼과 체득된 방법지로 구분되었다. 암묵적 기여는 암묵성 정도에 따라 대리, 시범, 질의응답(Q&A) 세가지로 구분되었다. 7가지 지식기여 요소에 대한 평가는 양적 측면과질적 측면에서 이루어졌다. 본 연구는 조직구성원의 지식기여의 활동결과는 지식관리시스템(KMS)에 저장되는 것을 전제로 하고 있다. 지식관리시스템 상에서의 형식적 기여의 경우 양적인 평가에서는 게시건수 혹은 수행건수로, 질적인 평가에서의 평가는 조회건수나 만족도 평가, 요청 받은 건수 등으로 측정하였다. 이상과 같이 연역적 방법에 의해 평가요소 및 평가항목들을 개발하고 각 평가항목들에 대한 가중치분석을 위해 전체를 100으로 하였을 때의 각 항목의 가중치를 정하기 위해 전문가들의 의견을 조합하는 델파이기법이 사용되었다. 델파이 결과, 형식적 기여 차원과 암묵적 기여 차원에 동일한 가중치가 부여되었으며, 형식적 기여차원에서는 사실지 보다는 방법지에 가중치가 좀더 부여되었고, 암묵지 기여 차원에서는 질의응답 - 시범 - 대리의 순으로 가중치가 부여되었다. 이를 통해 '타인의 지식 획득과 활용에 도움을 주는 지식기여행위가 되기 위해서는 어떤 형태로든 지식 제공자와 지식 수여자간의 밀접한 상호작용이 높아야 하며, 제공자의 지식이 타인에게 빠르게 그리고 잘 전달될 수록 지식기여도가 높다'라는 결론이 도출되었다. 본 연구는 지식기여 활동에 대한 평가 지표를 마련하였다는 점에서 의의가 크다 하겠으나, 업종별이나 산업별로 세분화된 평가 지표 마련에는 미흡하였다. 또한 항후 지식 경영을 도입하여 시행한 연수에 비추어서 평가 항목별 가중치를 부여를 할 수 있다면 보다 정교한 평가도구의 제공이 될 수 있을 것으로 보인다.

• Membrane and Water Treatment
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• 제9권6호
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• pp.435-445
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• 2018

In this work, desalination experiments were performed on vacuum membrane distillation (VMD). Process parameters such as feed flow rate, vacuum degree on permeate side, feed bulk temperature and feed salt concentration were optimized using sensitivity analysis and Taguchi method. The optimum values of process parameters were found to be 2 lpm of feed flow rate, $60^{\circ}C$ of feed bulk temperature, 5.5 kPa of permeate-side pressure and 5000 ppm of salt concentration. The permeate flux at these conditions was obtained as $26.6kg/m^2{\cdot}hr$. The rejection of salt in permeate was found to be 99.7%. The percent contribution of various process parameters using ANOVA results indicated that the most important parameter is feed bulk temperature with its contribution of 95%. The ANOVA results indicate that the percent contribution of permeate pressure gets increased to 5.384% in the range of 2 to 7 kPa as compared to 0.045% in the range of 5.5 to 7 kPa.