• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.9B
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• pp.563-568
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• 2007

This paper proposes a routing establishment method for improving path stability in mobile ad-hoc networks. In mobile ad-hoc networks, the network topology is highly dynamic due to the node mobility unlike wired networks. Since the existing methods are based on the shortest path algorithm with the minimum hop count regardless of the path stability, it could lead to packet loss and path disconnection in mobile ad-hoc networks. In particular, if control packets and critical data are transmitted on the unstable path, it causes serious problems. Therefore, this paper proposes one approach in order to minimize packet loss and path disconnection by considering the node mobility. After the destination node receives multiple RREQ messages, it selects the stable path through the proposed MinMax algorithm according to the node speed.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.303-311
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• 2015

The purpose of this study was to investigate the relationship between environment problem recognition, eco-friendly attitude, and eco-friendly nursing practice. A self-reported questionnaire was completed by 191 hospital nurses from October to November, 2012. The data were analyzed through t-test, one way ANOVA, Pearson correlation analysis, and multiple regression analysis. There was a positive correlation between environment problem recognition (r=.46, p<.001), eco-friendly attitude (r=.36, p<.001), and eco-friendly health care in the hospital nurses. The explanatory power of the variables accounted for 35.0%. This study indicated that it is necessary to promote the awareness towards environment problem and eco-friendly attitude in the hospital nurses in Korea.

• Journal of Engineering Education Research
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• v.11 no.3
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• pp.70-77
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• 2008

This study investigates the level of the construction student's familiarity and interest in sustainability, their attitude toward sustainability, and the factors for bringing student's attitude toward sustainability. To accomplish the main objectives, this study employes a survey instrument created and developed by the authors. This is a descriptive and correlation study using responses from construction students at the Building Construction department at Virginia Polytechnic Institute and State University in Virginia. The results of descriptive statistics and multiple regression using SPSS version 16 present the following findings. Construction students perceive that they have a relatively high level of familiarity with sustainable construction and sustainability. Secondly, student's attitude toward sustainability is changed based on several factors such as sustainable construction courses, a professor who is interested in sustainability, their interest in the construction industry, university initiative, and the level of sustainability for student's learning facilities. Finally, the construction student's attitude toward sustainability can be improved by offering sustainable construction courses in construction programs, having professors who teach and research sustainability, and adopting sustainable initiatives at the university level such as campus recycling and various sustainable programs.

• Korean Journal of Ecology and Environment
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• v.41 no.3
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• pp.275-282
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• 2008

Water hardness is a significant parameter as related to aquatic toxicity of some heavy metals. Hardness dependent metals include cadmium, copper, chromium (III), nickel, lead, zinc and silver. Developed countries have applied the hardness correction procedure to derive the water quality criteria for protecting the aquatic organisms. In the present study, we investigated the hardness correction algorithms used in United States of America, European Union, Australia/New Zealand, and Canada, and analyzed the details associated with those algorithms. Toxicity values of heavy metals were definitely different after hardness correction for all of algorithms analyzed. We found that the hardness corrected toxicity values followed by the algorithms of USA and Australia/New Zealand were very similar or same, however they were slightly different for cadmium at the hardness less than 30 mg $CaCO_3\;L^{-1}$. Among the hardness correction algorithms studied, the algorithm used in Australia/New Zealand appears to be a good choice to apply in Korean situation due to its simplicity compared to the algorithm of USA.

• Culinary science and hospitality research
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• v.21 no.4
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• pp.192-206
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• 2015

A study was conducted on dietitians in the Gyeonggido area to analyze the effect of purchase decision and attitude related factors regarding environmental-friendly agricultural products. The results of the factor analysis, correlation analysis and a multiple regression analysis are as follows. Many dieticians prefer environmental-friendly agricultural products, but they are reluctant to pay more money to purchase them. It was found that purchasing decision factors were 'loyalty' at 0.920, 'perceived quality' at 0.791, 'awareness' at 0.862, and 'brand' at 0.801. To conclude, the research result shows a statistically very close and positive correlation between the dieticians' attitude on environmental-friendly agricultural products and purchase decision. Other factors of quality(r=.296, p<.01), brand(r=.350, p<.01), loyalty(r=.558, p<.01), and awareness (r=.496, p<.01) acted as the most meaningful and significant variables. In short, of the dieticians surveyed in Gyeonggido province, the more favorably disposed to organic products, the more likely they are to purchase them. Accordingly, it is necessary for dieticians to be educated so that they may have greater awareness of environmental-friendly agricultural products. Furthermore, there is a need for more follow-up studies in order to gain an understanding of how to improve dieticians' attitudes on using organic products.

• International Commerce and Information Review
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• v.14 no.4
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• pp.49-59
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• 2012

The development of green IT for business will open up exciting opportunities for finding new and efficient way of doing businesses. This study is to contribute to a better understanding of green IT by carrying out the survey among IT users on the factors of green IT and IT users' perception to the GIT. Based on the literature study, a conceptual framework of green IT will be developed to investigate the relationship between green IT and the user's intention to use GIT.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.79-80
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• 2023

본 연구에서는 자율운항선박이 복잡한 항계 내에서 다양한 해상 객체와의 충돌을 회피하기 위하여 계층적 경로 생성 기법을 연계하는 프레임워크를 제안한다. 항계 내에는 항로를 항행하는 선박 외에도 정박 영역 내 정박 또는 묘박 중인 선박뿐만 아니라 항로 표지나 부표와 같은 정적 객체들이 다양하게 분포되어 있다. 자율운항선박의 효율적 운항을 위해서는 운항 중에 조우하게 되는 객체의 정적/동적 속성에 따라 경로 생성 기법이 달리 적용되어야 한다. 본 연구에서 제안한 경로 생성 프레임워크는 항계 내의 정적 객체나 항행 가항 영역 및 항행 불가항 영역 등에 대한 위치 정보들은 사전적 정보로 활용 가능하므로, 샘플링 기반의 전역 경로 생성 기법을 적용하여, 초기 출발지에서 최종 목적지까지의 예상 경로를 생성한다. 그리고 생성된 전역 경로를 추종하며 운항하는 과정에서 조우하게 되는 동적 객체들과의 조우 상황별 국제해상 충돌예방규칙(COLREGs)을 고려한 지역 경로를 생성한다. 샘플링 기반의 전역 경로와 국소 영역에서의 충돌 회피를 위한 지역 경로를 연계하기 위한 계층적 경로 생성 프레임워크를 설계하고, 수치 시뮬레이션을 통해 제안한 프레임워크의 유용성을 검증하였다.

• Journal of Forest and Environmental Science
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• v.8 no.1
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• pp.21-33
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• 1992

This study was performed to investigate the hardness of wood related to the wood surface, sap and heartwood, early and latewood, specific gravity, annual ring width and moisture content on major Korean tree species such as Pinus koraiensis, Abies holophylla, Larix leptolepis and Quercus valiabilis. The results were summarized as follows: 1. The arithmetic mean values of wood hardness on cross section were respectively $8.0kg/mm^2$ on Quercus valiabilis, $7.4kg/mm^2$ on Larix leptolepis, $5.1kg/mm^2$ on Pinus koraiensis and $4.7kg/mm^2$ on Abies hollophylla. 2. Generally hardness of wood on cross section was greater than the others and the proportion of cross section hardness to radial was respectively 2.8 on Quercus valiabilis, 2.6 on Larix leptolepis, 3.8 on Pinus koraiensis, and 4.1 on Abies holophylla and that proportion was tend to be decrease as specific gravity increased. 3. It was recognized that the hardness of sap and heartwood was different from each of the tree species and generally heartwood hardness was somewhat greater than sapwood. 4. Generally latewood hardness with in a ring was greater than earlywood and the proportion of earlywood hardness to latewood decreased as specific gravity increased. 5. The relations between hardness of wood and specific gravity show a high positive correlation on all sample tree species. 6. The values of hardness decreased with increasing annual ring width. 7. Hardness of wood on Abies holophylla was greatest in oven dried wood and it was decreased as moisture content increased, but not changed with moisture content abve F.S.P.. The proportion of oven dried wood hardness to green are respectively 3.0 on cross, 2.4 on radial and 1.9 on tangential section.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.114-119
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• 2013

The superiority and safety of eco-friendly agricultural products are well-known. The purpose of this study is to provide fundamental data for creating a safe food culture, to improve the quality of school food services, and to increase student satisfaction with school food services. We compared the perception of eco-friendly agricultural products and food service satisfaction between students with and without exposure to a dedicated event for learning about eco-friendly products (an Eco-friendly Food Service Day) in elementary and middle school. When students were asked to define eco-friendly products, "organic products" was a highly frequent response in schools with an Eco-friendly Food Service Day, while "pesticide-free products" was a highly frequent response in school without this event. For most students, a factor in choosing eco-friendly products was a quality certification mark. Students from elementary schools with an Eco-friendly Food Service Day had a higher frequency of using eco-friendly agricultural products at home compared to students from schools without the event (p<0.01). In addition, the satisfaction with school food service was higher in schools with an Eco-friendly Food Service Day (p<0.05). These results suggest it is important to promote the use of superior and safe eco-friendly agricultural products while developing a variety of menus considering students' preferences.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.6 s.324
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• pp.49-58
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• 2004

The existing route re-establishment methods which intend to extend the lifetime of the network attempt to find a new route in order not to overly consume energy of certain nodes. These methods outperforms other routing algorithms in the network lifetime aspect because that they try to consume energy evenly for the entire network. However, these algorithms involve heavy signaling overheads because they find new routes based on flooding method and route re-establishment occurs often. Because of the overhead they often can not achieve the level of performance they intend to. In this paper, we propose a new route selection algorithm which takes into account costs for the packet transmission and the route re-establishment. Since the proposed algerian considers future route re-establishment costs when it first find the route, it spends less energy to transmit given amount of data while evenly consuming energy as much as possible. Simulation results show that the proposed algorithm outperforms the existing route re-establishment methods in that after simulation it has the largest network energy which is the total summation of remaining energy of each node, the smallest energy consumed for route re-establishment, and the smallest energy needed for maintaining a session.