• Korean journal of applied entomology
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• v.42 no.3
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• pp.249-255
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• 2003

These studies were carried out to investigate fumigant, contact toxicity and repellency effects of 34 terpenes against acaricide susceptible the two-spotted spider mite, Tetranychus urticae. In addition, the efficacy was also tested against two acaricide-resistant strains. Two terpenes, isosafrole and safrole showed fumigant toxicity of 98.4%, at 10${\mu}\ell$/1 (air) concentration. LD$\_$50/ values of these two terpenes were 2.6${\mu}\ell$/1 and 4.3${\mu}\ell$l/1, respectively. Most terpenes showed low or no contact toxicity, except isosafrole showing 60.2% mortality against eggs. Hexanoic acid and limonene showed repellency effects of 79.1%, 87.8%, respectively, to the susceptible strain at concentration of 1,000 ppm in the lab conditions. Hexanoic acid (1,000 ppm) showed repellency effected of 77.8% and 83.3% to fenpropathrin and pyridaben resistant strains, respectively. However, limonene showed no repellency to the two resistant strains.

• Journal of Korean Society of Steel Construction
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• v.19 no.1
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• pp.29-41
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• 2007

Structural design, like other complex decision problems, involves many trade-offs among competing criteria. Although mathematical programming models are becoming increasingly realistic, they often have design limitations, that is, there are often relevant issues that cannot be easily captured. From the understanding of these limitations, a decision-support system is developed that can generate some useful alternatives as well as a single optimum value in the optimization of steel frame structures. The alternatives produced using this system are "good" with respect to modeled objectives, and yet are "different," and are often better, with respect to interesting objectives not present in the model. In this study, we created a decision-support system for designing the most cost-effective moment-resisting steel frame structures for resisting lateral loads without compromising overall stability. The proposed approach considers the cost of steel products and the cost of connections within the design process. This system makes use of an optimization formulation, which was modified to generate alternatives of optimum value, which is the result of the trade-off between the number of moment connections and total cost. This trade-off was achieved by reducing the number of moment connections and rearranging them, using the combination of analysis based on the LRFD code and optimization scheme based on genetic algorithms. To evaluate the usefulness of this system, the alternatives were examined with respect to various design aspects.

• Journal of Korean Society of Steel Construction
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• v.19 no.1
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• pp.15-27
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• 2007

Over the past decade, labor costs have increased relative to the cost of material hardware according to analysts in the construction industry. Therefore, the minimum weight design, which has been widely adopted in the literature for the optimal design of steel structures, is no longer the most economical construction approach. Presently, although connection- related costs is crucial in determining the most cost-effective steel structures, most studies on this subject focused on minimum-weight design or engaged in higher analysis. Therefore, in this study, we proposed a fabrication scheme for the most cost-effective moment-resisting steel frame structures that resist lateral loads without compromising overall stability. The proposed approach considers the cost of steel products, fabrication, and connections within the design process. The optimal design considered construction realities, with the optimal trade-off between the number of moment connections and total cost was achieved by reducing the number of moment connections and rearranging them using the combination of analysis that includes shear, displacement and interaction value based on the LRFD code and optimization scheme based on genetic algorithms. In this study, we have shown the applicability and efficiency in the examples that considered actual loading conditions.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.117-127
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• 2018

When we face an unexpected challenge, should we stick to the original plan and persevere through the series of challenges? Or shall we pivot and transform our original plan into something new by taking into account the newly acquired information? This perennial question of perseverance versus pivot as two competing problem-solving strategies has puzzled our every day lives. In this study, based on the large-scale, nation-wide survey on entrepreneurship, I found that individual entrepreneurial orientation, which consists of innovativeness, risk-taking, and proactiveness, promotes an individual's tendency to choose new problems to solve. Perseverance strategy was found to positively moderates the relationship between innovativeness and the tendency to choose new problems to solve, whereas the relationship between risk-taking and the tendency to choose new problems to solve was found to be negatively moderated by perseverance strategy. Pivot strategy, on the other hand, was found to be positively moderates the relationship between proactiveness and the tendency to choose new problems to solve. These findings contributes to the stream of individual entrepreneurial orientation research by empirically testing two competing problem-solving strategies of perseverance and pivot to show their interaction effects with entrepreneurial orientation. Also the findings of this study expand the potential outcome of entrepreneurial orientation by adding an individual's tendency to choose new problems to solve rather than what he or she has already experienced before.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.5
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• pp.543-561
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• 2020

This paper is the result of the study on the effect of the support structure of the tunnel steel rib. In tunnel excavation, the top and bottom half excavation methods result in subsidence of steel rib reinforcement due to insufficient support of steel rib reinforcement when the ground is poor after excavation. The foundation of the steel rib installed in the upper half excavates the bottom part of the base, causing the subsidence to occur due to various effects such as internal load and lateral pressure. As a result, the tunnel is difficult to maintain and its safety is problematic. To solve these problems, steel rib support structures have been developed. For the purpose of verification, the behavior of the supporting structure is verified by model experiments reduced to shotcrete and steel rib material similarity, the numerical analysis of ΔP and ΔP generated by bottom excavation by Terzaghi theoretical equation. As a result, it was found that the support structure of 20.100~198.423 kN is required for the 10~40 m section of the depth for each soil of weathered soil~soft rock. In addition, as a result of the reduced model experiment, a fixed level of 50% steel rib deposit of steel rib support structure was installed. The study shows that the installation of steel rib support structures will compensate for uncertainties and various problems during construction. It is also thought that the installation of steel rib support structure will have many effects such as stability, economy, and air reduction.

• Management & Information Systems Review
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• v.38 no.4
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• pp.95-111
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• 2019

This study aims to measure effects of cause-related marketing by using consumer's preference of cause-related marketing product as a dependent variable. One of main factors influence on preference of cause-related marketing product is a product type. Previous research has shown that hedonic product is more effective for cause-related marketing than utilitarian product. The result was largely explained by the logic of guilt. However, there were conflicting results. In addition, the level of guilt may vary depending on the consumer characteristics or the market environment. Therefore, this study focuses on the impact of product type on the effect of cause-related marketing. For the Korean and Chinese markets, this study examines the effect of interactions between countries and product type. The result was significant. Specifically, there was a difference in preference of cause-related marketing product between Korean and Chinese consumers by product type. Based on the findings, implications and limitations of this study and future research directions were presented.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.99-104
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• 1993

생산자동화기술을 도입하여 도입성과를 향상시키려면 자동화기술을 도입하고 활용함에 있어서 성공요인들을 문헌과 현장의 사례들을 통하여 충실히 검토하고 종합적으로 분석한 후에 이를 생산시스템에 적용할 때에는 자동화기술의 상반관계(trade-off)에 있는 성과변수를 동시에 향상시켜 경쟁력을 갖게 될 것이다. 기업전략과 생산전략을 수립하고 그 틀 안에서, 생산자동화기술 추진전략을 세워 전략사이의 적합성이 높을 때 자동화기술 도입성과는 크게 향상될 것임을 유념해야 한다. 따라서 본 연구에서 제시한 생산자동화기술 성공요인이 자동화기술 도입성과에 영향을 미치므로 자동화기술 추진전략이 기업의 능력범위 안에서 이들 요인을 잘 반영하고 있는지를 검토하고, 분석한 후에 종합적으로 판단하여야 한다. 이러한 과정을 거쳐 자동화기술이 도입되고 운영될 때 자동화기술 도입효과는 극대화될 수 있다.

• Knowledge Management Research
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• v.18 no.4
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• pp.119-136
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• 2017

This paper focuses on proactive personality as one of the main personality traits relevant to knowledge sharing and examines how this personal trait influences knowledge sharing behavior. Moreover, in order to consider the interactive effect between proactive personality and a contextual factor, this study utilized the construct of LMXSC which can reveal restoration of resource losses due to knowledge sharing. Because LMXSC can have opposite directions depending on used theories, this study investigates how LMXSC moderates the relationship between proactive personality and knowledge sharing behavior by using conservation of resources theory and trait activation theory. This study tests hypotheses with the data of supervisor-employee dyads in various industries. An empirical results showed that proactive personality increased knowledge sharing behavior and LMXSC strengthened the positive relationship between proactive personality and knowledge sharing behavior as conservation of resources theory predicts. Based on these theoretical arguments and empirical findings, this study suggests theoretical and practical implications, limitations, and the directions of future research.

• Knowledge Management Research
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• v.12 no.5
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• pp.11-23
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• 2011

The objective of this study was to analyze the two contrary effects of usage habits on the acceptance of a new IT. The one is a positive one which may be caused by expertise from the repetitive usages of a current system while the other is a negative one which would be due to lock-in. For this purpose, this study suggested three hypotheses which account for not only the negative effect of the habit in current system on the intention of using a new system but also the positive moderation effects on both relationships of perceived usefulness and perceived ease of use with the intention of a new system. For the empirical tests of the hypotheses, this study surveyed acceptance of Google Docs for the users who have a habitual used word processor. The analysis by partial least square approach showed that the hypotheses were statistically supported.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.41-46
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• 1997

TiN 코팅은 마모에 대한 저항성 및 고체 윤활 효과가 매우 우수하여 내마모성 및 저마찰이 요구되는 절삭공구나 피스톤 베어링 및 각종 축계의 코팅막으로 사용이 증가되고 있다. 일반적으로 재료의 경도와 인성은 서로 상반 관계를 갖고 있어 공학적으로 경도와 인성을 모두 요구하는 표면을 얻기 위해 연질 모재 위의 세라믹 코팅은 그 요구를 만족시킬 수 있는 가장 각광받는 표면처리 방법중의 하나이다. 그러나, TiN과 같은 경질 박막의 공학적 적용시 가장 요구되는 마모수명은 모재의 조도나 경도, 증착 방법, 접촉 상태, 코팅막의 두께 및 마모의 발생 기구 등에 따라 마찰 및 마모 메커니즘의 현저한 차이를 나타내기 때문에 예측이 거의 불가능한 실정이고, 아직까지 이러한 마모수명 비교 평가방법에 대한 기준 설정 및 정량적 정립이 이루어지지 않고 있다. 본 연구에서는 모재의 경도, 조도, 코팅 두께가 다른 TiN 경질 박막에 압입시험과 스크래치시험시 발생되는 균열 발생 메커니즘과 미끄럼 시험시 발생되는 마모 메커니즘의 연계성을 밝히고 압입 및 스크래치 시험시 코팅막이 손상되는 임계하중과 미끄럼 시험시 접촉하중 변화에 따른 마모수명의 정량적 연관성을 찾아보고자 한다.