• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.358-364
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• 2011

To examine the possibility of natural regeneration of six Acer species in broadleaved mixed forest in Korean peninsula, samples of six Acer species' samaras were collected at several seed sources from September to October 2009 and 2010, and seed morphological characteristics and viability were studied using cutting method. Inflorescense type of Acer mandshuricum(AM), A. pseudosieboldianum(APS) and A. palmatum(AP) is corymb, that of A. pictum subsp. mono(APSM) and A. okamotoanum(AO) is flat-topped panicle, and that of A. ukurunduense(AU) is raceme. Number of seed-set per inflorescense proves the highest value 38.5 sets in AU and the lowest value 2.4 sets in APS. Diameter of the seeds proves highest value 13.5mm in AO, and the lowest value 4.7mm in APS. Angles between the wings proves the highest values $130.05^{\circ}$ in APS, and the lowest value $48.60^{\circ}$ in AU. Air dry weight of 20 seed-sets proves highest value 3,900mg, in AO, and the lowest value 404mg in AU. Viable seed ratio of AP proves 50%, and that of AU does 43.2%. Those of other four species ranges 8.6~22.2%. Considering postdispersal seed predators and disturbance of litter, viable seeds of APSM, AO, AM, and APS supplied in the natural forest in Korea might be insufficient for seedling establishment. This study showed that sound viable seed supply might be key factors of natural regeneration of major Acer species in Korea. The openings made by insect pests were observed on the seed-coat of APSM, AM, AU, and APS samara, and Bradybatus sharpi were observed in the samaras of APSM and AO. Further study on the seed insect fauna, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.10
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• pp.937-945
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• 2014

As various services requiring high data rate are supported by introducing LTE/LTE-adv., mobile traffic increases rapidly. To cope with the continuous growth of traffic demand, small cell technology is considered as one of the most promising one. Small cell can increase system capacity by increasing the number of base stations with reduced cell radius. In this paper, we analyze the effect of cell densification with small cells in terms of SINR and average UE throughput considering cell split and the number of UE per unit area. As the cell becomes smaller, SINR degradation arises from high ICI(Inter Cell Interference) and we evaluate the effect of interference mitigation scheme in small cell environment where the proper interference mitigation technique is applied.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4D
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• pp.323-333
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• 2012

This paper is aimed to recognize trends of various social groups about multiple transportation policies such as the crosswalk restoration by eliminating the pedestrian overpasses and the improvement or continuous extension of existing pedestrian overpasses, currently implemented in Busan, following the globally prevailing pedestrian-oriented transportation environment. Also, this paper utilizes Contingent Valuation Method (CVM) to evaluate the efficiency of individual alternatives in terms of respondent's willingness-to-pay (WTP). Consequently, survey participants preferred the crosswalk or improvement of the pedestrian overpasses rather than depending on the existing pedestrian overpasses. In addition, the WTP value for the crosswalk restoration is approximately 42,452 won per household per year, and, on the other hand, the WTP value for the improvement of existing pedestrian overpasses is approximately 36,793 won per household per year, implicating that the transportation policy makers are suggested to place more priorities on crosswalk restoration than the improvement of the existing pedestrian overpasses.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.3 s.73
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• pp.223-231
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• 2006

This study deals with behavior characteristics of laminated composite folded structures according to ratio of folded length based on a higher-order shear deformation theory. Well-known mixed finite element method using Lagrangian and Hermite shape interpolation functions is a little complex and have some difficulties applying to a triangular element. However, a higher-order shear deformation theory using only Lagrangian shape interpolation functions avoids those problems. In this paper, a drilling degree of freedom is appended for more accurate analysis and computational simplicity of folded plates. There are ten degrees of freedom per node, and four nodes per element. Journal on folded plates for effects of length variations is not expressed. Many results in this study are carried out according to ratio of folded length. The rational design is possible through analyses of complex and unpredictable laminated composite folded structures.

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.71-79
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• 2014

The goal of this study is to estimate economic benefit of restoring ecological stream of Hong Cheon river. The benefit is determined by estimating willingness-to-pay for the value of Hong Cheon river because it is a non-market good which is difficult to be measured in terms of monetary value. Specifically, the spike model, one of the contingent valuation methods, is used to distinguish respondents having zero willingness-to-pay for Hong Cheon river. The results show that a household located near the Hong Cheon river is willing to pay 3,300~4,628 Korean Won per year, while a household not located near the Hong Cheon river is willing to pay 1,308~2,929 Korean Won per year. Thus, total benefit of restoring ecological stream of Hong Cheon river is estimated as 97.6~216.3 billion Korean Won.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.24-29
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• 2002

The social attention about disaster psychiatry was increased after 911 terror in New York. The role of child psychiatrist and specific consideration for the treatment of child victim in disaster were reviewed. The following were main points. 1) The most single determining factor of prognosis is supporting system and parental attitude to their child victim. So family therapy and parental eucation are needed. 2) Cognitive Behavior Therapy is known to the most effective treatment in many literature. 3) Brief group therapy with fellow victim is cost effective preventive methods and screening tool for more serious victim, 4) Eye Movement Desensitization and Reprocessing(EMDR) could be a very amazing method in reducing repetative horrible traumatic image. 5) Many kinds of drug using in adult are considered with caution.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.447-451
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• 2003

When sowing green peas in the autumn, proper seedling stands and growth quantity should be secured before winter begins. Also, for proper acclimatization, injuries caused by low temperatures, frost or high temperatures in the P.E. film during mulching, should be avoided during the regeneration period; that being early spring. The days required for growth in each stage in Yeosu are shorter than those in Naju because Yeosu has high temperatures during the growth period. Furthermore, in Yoesu, it was observed that there were more effective branches as well as effective and attached node positions on the branches. The first pods on the main stems and effective branches were observed to be higher than those in Naju. The number of pods per plant and the number of seeds per pod in Yoesu was greater than for those in Naju and the pod length was longer as well. Considering the missing plant rate, growth, and green pod yield, the optimum sowing date for the green pea was mid-November in both location. The stable acclimatizing date for the green pea was early March when the highest yield can be acquired due to a lot of effective branches and pods per plant and with the lowest missing plant rate and rate of injury in acclimatization.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.446-449
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• 1998

Dental caries suppression effect and other physiological properties of erythritol were measured in comparison with those of sucrose, xylitol and sorbitol. The susceptibility test for dental caries by using Streptococcus mutans KCTC 3065 and Lactobacillus acidophillus indicated that erythritol was as effective as xylitol in suppressing dental caries. In lactic acid fermentation test, erythritol showed the least growth of bacteria among the tested sweeteners. The tolelerance test by using mice showed that diarrhea began by feeding once 1500 mg erythritol/kg b.w., 1500 mg xylitol/kg b.w. and 1000 mg sorbitol/kg b.w. respectively.

• Journal of Environmental Policy
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• v.9 no.2
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• pp.135-155
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• 2010

The purposes of the paper are to estimate welfare change from water quality degradation by using contingent valuation method in Namdae stream of Gangrung and identify what factors of Namdae stream are important to Gangrun citizens. The study results show their total WTP per year and per household, \117,040 to improve Namdae stream quality from grade 3 to grade 1, including monetary WTP \87,502 plus opportunity cost of volunteering time for protection campaign, \29,538. The amount of total welfare change from water quality degradation based on the total WTP estimated above is calculated to be \27 billion of which the amount, as a sort of damage cost from water quality degraded, is so huge. All projects and policies related to natural environments, therefore, should consider both indirect and direct effects from them because natural environments have the irreversibility once degraded or deteriorated and would ultimately be influential on humans, both current and future generations, with tremendous amounts of time and costs beyond our imagination.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.4
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• pp.667-675
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• 2016

The goal of this study is to be used as baseline data for transportation demand management. At the present time the number of registered car and householding car is increasing, so there is a need to analyze the car ownership pattern through household car hold status. Also, it is necessary to analyze the factor of increasing car. The research is proceeded with classifying as the household which is holding private cars or holding passenger cars and non passenger cars based on the result of the research of the household travel survey data. The result of this study is shown as follows. According to car ownership pattern, there are more households holding passenger cars only when they are holding less than 2 cars. Otherwise there are more households holding passenger car and non passenger car when they are holding more than 3 cars. Using the Ordered Logit Model, there are more differences in factors affects holding cars by variables of housing type and household properties.