• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.480-485
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• 1994

Growth and wood quality characters such as height, DBH, specific gravity, traceried length and width were measured for 16-year-old open-pollinated progenies of 38 selected plus trees of Abies holophylla Max. The results were as follows ; 1) The superior families in growth and wood quality characters were Chonbuk 4(498.2cm) and Kyonggi 9(485.7cm) for height, Kyonggi 12(9.2cm) and 9(9.1cm) for DBH, Kaongbuk 2(0.480) and Kangwon 7(0.473) for specific gravity, Kyonggi 9(2.77mm) and Kangwon 11(2.71mm) for tracheid length and Kyonggi 9(0.039mm), Kangwon 11, 12 and Kyunggi 7(0.036mm) for tracheid width, respectively. 2) There were significant differences among the families in height and specific gravity at 1% and 5% level. 3) There were high significant negative correlations between specific gravity and other characters such as height, DBH, tracheid length and width at 1% level($r=-0.242^{**}{\sim}-0.635^{**}$) 4) The heritabilities were 0.55 for height, 0.25 for DBH, 0.44 for specific gravity, and 0.24 for tracheid width.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.181-188
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• 2003

Frequencies of each size class, annual change of tuber state and above ground/belowground rate in sect. Pes-gallinaceua group of Corydalis (Fumariaceae) were studied to clarify spring ephemeral´s growth characteristics from 1999 to 2000 in Namhansansung area. Shoot grew from the tuber corresponding with soil thawing in the early growth season, and the deeper tuber was located in soil, the later shoot germinated. Shoot appeared in middle March and died early in May, and the period of total growth season was 45 days. Frequencies were 40% (in total dry weight) or 53% (in tuber´ dry weight) in the smallest size class, and 93% (in total dry weight) or 96% (in tuber´ dry weight) below medium size, therefore, almost all of plants were small. Specific gravity of tuber (SGT) gradually decreased from late growth season to the time that leaf unfolded in next year. At this time, the value of SGT was 0.14. Thereafter, SGT increased to 0.42 at withering time of aboveground part. During growth season, the SGT of flowering plants was lower than that of non-flowering plants. And SGT difference between flowering plants and non-flowering plants was significant at 1% level. In the late growth season, SGT decreased along the increase of tuber volume. The tuber volume roughly increased along the leaf area but there was no a conspicuous trend. Shoot/tuber rate had nothing to do with tuber volume. SGT decreased and leaf area increased along the tuber dry weight, and tendencies of increase or decrease were conspicuous. Therefore, the smaller the plants were, the larger organic matter accumulated in tuber during a growth season. Shoot/tuber rates were various along each plant.

• Journal of The Korean Association For Science Education
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• v.36 no.5
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• pp.717-727
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• 2016

Using TIMSS survey data, we analyzed whether there were any significant changes in the learning environment of middle school science classes over the last 10 years. Our study selected questions from teachers and school principals' questionnaires and divided them by category: science class, teacher professional development, and school environment. The science class components were subdivided into three categories: science learning activities, evaluation, and homework. Within teacher professional development, the sub-categories included teacher training, collaboration to improve teaching, and teacher evaluation. School environment subdivided into two aspects, these being school characteristics and school system. Our research confirmed that there has been a positive change overall in learning environments. However, most classes are teacher-conducted and also teacher-oriented; the proportion of science investigation activities has declined compared against the prior ten years. Our study show that students do not engage in a range of inquiry-related activities. The questions on tests and examinations involve mostly knowledge application and understanding, although recent methods of evaluation show improvement. As for the science teachers, they participate in many professional development programs but focus on science content, science curriculum, and pedagogy. In addition, teachers do not have many opportunities to participate in the training to integrate information technology into science, science assessment, or improving students' critical thinking or inquiry skills. The teachers are satisfied with their profession, and the shortage of science resources does not seem to affect instruction.

• Korean Journal of Construction Engineering and Management
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• v.11 no.1
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• pp.59-69
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• 2010

Although international construction market gradually takes a important position among the export industries, the previous studies about international construction entry strategy have just focussed on trend investigation or suggestion for revitalization. Moreover, in order to prepare the market uncertainty such as world financial crisis and to plan the long term strategy, specific strategy studies based on corporate level are required. Therefore, this study estimates the nine strategic index and four financial index of 31 companies that performed 1920 international projects from 1993 to 2007 and evaluate the performance as three periods by multi-regression analysis. Also, this study analyze dynamic correlation between these index and the performance considering times. this study verifies that market diversification, product diversification, localization and decrease of debt to asset ratio make a good effect on the international order as long term strategy and shows that collaborated entry with domestic corporations, alliance entry with host country's company, alliance entry with third country's company, portion of labor cost and portion of management expense differently make a influence on the performance as times. these results will be helpful for the construction companies to plan the international entry strategy reasonably and specifically.

• Management & Information Systems Review
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• v.31 no.4
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• pp.33-56
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• 2012

The purposes of this paper are analysed the relationship between environmental regulation and financial performance in Korea. The financial performance of listed companies and Outside Auditing firms was evaluated by logistic regression. First, R&D investment is proportionally correlated with the ability to comply with environmental regulations. It can be explained increase of investment in R&D causes enhancement of compliance of environmental regulations with development of environmental technology. Second, statistical significance is not observed between financial aspects such as current ratio, debt-to-equity ratio, cash flow, and operating profit margin and the ability to comply with environmental regulations. It indicates high financial performance could not directly lead investment for the ability of that. Third, in terms of structural aspects, firm size and employees have a reliable correlation with compliance with environmental regulations due to high attention of larger firms for PR, and IR, while capital intensity and gravity, and exports do not. Finally, violation of environmental regulations is not affect by the controlling shareholder ownership.

• Journal of Environmental Policy
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• v.10 no.2
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• pp.21-44
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• 2011

It is important to consider an equitable allocation framework for domestic GHG emission reduction. First, the study established criteria and indicators for the National Allocation Plan (NAP) based on the principles of cost-efficiency and social-acceptance, and performed a case study of the sectoral effort sharing method, using the effort sharing index. The equity analysis of effort sharing based on sectoral preferences and inter-sectoral equity using a Lorenz Curve are performed. The equitable method is more likely to be suitable than the economic one which considers just reduction potential. Equitable effort sharing reflects a higher level of equity than economic effort sharing. At the same time, the equitable effort sharing method is essential for reflecting equity and establishing criteria for equity because evaluation with the equitable effort sharing method depends in particular on the weight of equity criteria. The result suggests the importance of consideration of equity and the establishment of equity criteria. In conclusion, it is critical to consider not only cost-efficiency but equity in policy decision making in terms of the sectoral effort sharing for national GHG reduction target.

• The KIPS Transactions:PartC
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• v.12C no.3 s.99
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• pp.429-436
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• 2005

A mobile ad hoc network (MANET) is a collection of mobile nodes without any fixed infrastructure or my form of centralized administration such as access points and base stations. The ad hoc on-demand distance vector routing (AODV) protocol is an on-demand routing protocol for MANETs, which is one of the Internet-Drafts submitted to the Internet engineering task force (IETF) MANET working group. This paper proposes a new multipath routing protocol called maximally disjoint multipath AODV (MDAODV), which exploits maximally node- and link-disjoint paths and outperforms the conventional multipath protocol based on AODV as well as the basic AODV protocol. The key idea is to extend only route request (RREQ) message by adding source routing information and to make the destination node select two paths from multiple RREQs received for a predetermined time period. Compared to the conventional multipath routing protocol, the proposed MDAODV provides more reliable and robust routing paths and higher performance. It also makes the destination node determine the maximally node- and link-disjoint paths, reducing the overhead incurred at intermediate nodes. Our extensive simulation study shows that the proposed MDAODV outperforms the conventional multipath routing protocol based on AODV in terms of packet delivery ratio and average end-to-end delay, and reduces routing overhead.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.1
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• pp.369-377
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• 2013

This paper deals with the state of charge(SOC) and life cycle evaluation algorithm for lead-acid battery, which is essential factor of the electric vehicle(EV) and the stabilization of renewable energy in the smart grid. In order to perform the effective operation of the lead-acid battery, SOC and life cycle evaluation algorithm is required. Specific gravity with the change of electrolyte temperature inside battery case should be obtained to evaluate the SOC of lead-acid battery, however it is difficult to measure the electrolyte temperature of sealed type lead-acid battery. To overcome this problem, this paper proposes the equation of thermal transmission to compensate internal temperature of the lead-acid battery. Also, it is difficult to exactly evaluate the life cycle of battery, depending on the operation conditions of lead-acid battery such as charging and discharging state, self discharging rate and environmental issue. In order to solve the problem, this paper presents the concept for gravity accumulation of charge and discharge cycle, which is the value converted at $20^{\circ}C$. By using the proposed algorithm, this paper propose the test device based on the Labview software. The simulation results show that it is a practical tool for the maintenance of lead-acid battery in the field of industry.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.529-536
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• 2021

In this study, nano-silica and nano-titanium were selected to determine the possibility of applying the binder to reactive nano materials. The basic characteristics of the nano material candidate group were reviewed. and the reactivity of nano materials was reviewed through K-value. The reactivity of the nano silicate materials was measured to be high. Therefore, as a final candidate group, nano silicate materials were selected. The finally selected reactive nano material was reviewed for its usability as a construction binder. The mechanical properties and unit weight of cement paste were reviewed using silica fume and blast furnace slag and nano materials. When cement composites with nano silicate materials, it was confirmed that it was effective in improving the mechanical performance and decrease the unit weight of cement composites.

• International Area Studies Review
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• v.15 no.2
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• pp.125-150
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• 2011

As the economy grows, there is a concern that the economic development causes a productivity reduction because of the service intensive growth. However, the economy of developed countries encounter with the productivity growth as their economy grows, which phenomenon called Baumol's paradox. Oulton (1999, 2001) find out the reason of Baumol's paradox in a forward and backward chain effects. So, this paper is aimed at verifying the theory of Oulton (1999, 2001). Moreover, we test the difference effect between a consumer service and producer service input using a dummy variable. We use the Input-Output Table (1990, 1995, 2000, 2005) that is offered by the Bank of Korea to accomplish the purpose of our research that is represented above. We find out that the Korea's intermediate producer service inputs cause a multifactor productivity growth. That result is matched with the Oulton (1999, 2001)'s theory. But, the intermediate consumer service inputs don't have a significant effect on a multifactor productivity. The result of verifying the effect of intermediate producer service inputs among industries shows that the effects on manufacture industries are less than other industries.