• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.462-471
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• 1996

This study was conducted to investigate the effects of meteorological changes on tree growth due to the reservoir construction. First, climatic normals were estimated before and after the reservoir construction at the area of Imha, through the topoclimatological relationships. Secondly, the amount of meteorological changes was quantified based on the difference analysis of the climatic normals. Thirdly, the diameter increments of Pinus densiflora around Imha area were measured with increment borer. Sample trees were taken on the 6 points of 30m, 100m, 500m, 1km, 3km, and 5km from the reservoir, respectively. Finally, effects of meteorological changes on tree growth were investigated based on the analysis of tree ring increment patterns. Results showed that the growth of trees within the range of 1km from the reservoir had been increased, but the growth of ones out of 1km range had no relationship with meteorological changes after the reservoir construction. It seems that the diameter increment of trees grown near reservoir has been increased mainly due to the increased solar radiation in spring and the increased total amount of precipitation during growing season, compared with those before the reservoir construction. It is supposed, however, that the changes of monthly mean temperature has little effect on the tree growth because of its small amount of changes.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.444-454
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• 2016

This study was designed to examine the characteristics of sawdust and cocopeat bedding materials, including physicochemical properties (Exp. I) and on-farm trial (Exp. II). In Exp. I, the proportion of particle size was in the order of sawdust>cocopeat India>cocopeat Vietnam (p<0.05), and cocopeat contained higher proportion of small particles ($250{\mu}m$+below $250{\mu}m$) than sawdust, causing a dust production problem. Bulk density was cocopeat India>cocopeat Vietnam>sawdust (p<0.05), thus cocopeat treatments showed 4.4 times higher bedding cost than sawdust. The water absorption rates were 702.0% in cocopeat India, 678.3% in cocopeat Vietnam, and 444.0% in sawdust, showing cocopeat had approximately 1.5 times higher water absorption rate than sawdust. Moisture evaporation rates after 12 h of air blowing (2.00 m/s) were higher (p<0.05) in cocopeat Vietnam (80.4%) than sawdust (71.2%) and cocopeat India (72.8%). In vitro ammonia emissions were higher (p<0.05) in sawdust ($2.71mg/m^2/h$) than cocopeat India ($1.59mg/m^2/h$) and Vietnam ($1.22mg/m^2/h$), and total ammonia emissions were higher (p<0.05) in sawdust ($37.02mg/m^2$) than cocopeat India ($22.51mg/m^2$) and Vietnam ($13.60mg/m^2$). In Exp. II, an on-farm trial was conducted with 48 Hanwoo cattle in 16 pens using the same bedding materials as in Exp. I, with fan (blowing 2.00 m/s) and no fan treatments, and feed bunk side (FB) and water supply side (WS) within a pen (4.5 m, $width{\times}9.0m$, length). Beddings were replaced with fresh bedding materials when moisture concentrations were over 65%. No interactions among treatments were detected for moisture concentration and increment rates, and ammonia concentrations, but a significant effect was observed (p<0.01) for each of the treatments. Both concentrations and increment rate of moisture were higher (p<0.01) in the beddings without fan than with fan. Moisture concentrations and increment rate within a pen were also higher (p<0.01) in FB than WS. Thus, the whole no-fan-FB and sawdust-fan-FB were replaced with fresh bedding material between 4 to 5 experimental weeks. The ammonia concentrations and pH of beddings were not significantly different among treatments. Therefore, using cocopeat bedding with a blowing fan can extend twice the bedding utilization period, and WS within a pen showed twice the bedding-life compared to FB. Despite the outstanding characteristics of cocopeat compared with sawdust, using cocopeat as an alternative for sawdust bedding is not recommended for cattle management, considering it has 4.4 times higher bedding cost and a dust production problem.

• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.146-155
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• 1992

The natural mixed stand in Jindong-Ri, according to a recent study, showed the possibility of selection cutting as a silvicultural system based on the stand structure such as DBH distribution and height distribution. However, volume structure per DBH class of this stand had not a mature stand of selection cutting. In this study, wherefore, the rate of increment for DBH and volume was used to predict the future stand structure including volume distribution per DBH class. The possibility of selection cutting was then discussed using the future stand structure. From the prediction of future stand structure for 30 years per every 10 years, it could be concluded that the stand will be induced to selection cutting forest because of enough number of trees in objective DBH class and above, total volume per hectare, and the volume of large DBH class which can be harvested every year. However, this stand still did not show the structure of typical selection cutting which has the rate of 1 : 2 : 7 in the number of trees per hectare and the volume rate of 5 : 3 : 2 for large, medium, and small DBH class. This problem could be improved by appropriate silvicultural treatments.

• Korean Parent-Child Health Journal
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• v.6 no.2
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• pp.127-146
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• 2003

The purpose of this study is to investigate the seven-hour sexuality education program for senior high school girl students and apply it to them to find out how this program affects their sex-related knowledge, sexual attitudes, and the self-efficacy of sexual behavior practice. The ultimate goal of this study is that high school girl students are to prevent unwanted pregnancy, STD and AIDS, after attending this sexuality education program. A non-equivalent control group pretest-post test design was used for this study. The number of experimental group consisted of 80 girl students and the control group was composed of 80 girls, too. A total of 160 freshmen from two commercial girls' high schools were selected by a convenience sampling method. This study was carried out in commercial high schools located in Daejeon, Korea from July 15th to October 31st, 2002. To discover the need for sexuality education, the researcher surveyed with a pre-designed questionnaire to 160 girls from the two different commercial high schools. The sex education curriculum was developed on the basis of the need of high school girl students for sex education survey results and literature review and a teaching-learning planning model and health belief model. The experimental group was taught the sexuality education program for seven hours from October 19th to 23rd, 2002 and each period continued for 50 minutes. The SPSS(10.0) Windows statistics software was used to analyze the data, along with frequency, percentage, $X^2$-test, t-test, and paired t-test. The instruments' internal consistencies were tested by Cronbach's alpha coefficient. The results of this study were as follows: 1. The increment of sex-related knowledge score after seven hour sexuality education was significantly higher in experimental group (t=-10.88, p=.000). 2. The increment of sex-related attitude score after seven hour sexuality education was significantly higher in experimental group (t=-2.67, p=.009). 3. The increment of the practice of self-efficacy of sexual behavior score after seven hour sexuality education was significantly higher in experimental group(t=-4.95, p=.000). In conclusion, sexuality education programs based on high girl students' educational desire, characteristics of development, a teaching learning planning model, a health belief model were effective to improve sex-related knowledge, sexual attitudes and the self-efficacy of sexual behavior practice of commercial high school girl students. This result can contribute to expand the school nurse's role in the sex education area and to develop theory-based school health nursing.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2119-2123
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• 2007

This study deals with performance characteristics of heat pipe combined with a solid-liquid phase change material(PCM). The outer diameter of the heat pipe was 9.5 mm and the total length was 600 mm, where the evaporator, the adiabatic section and the condenser lengths were equally 200 mm. A paraffin wax having a melting point of 58.5$^{\circ}C$ was used as PCM. The paraffin container was attached to the adiabatic section of the heat pipe. The paraffin container had outer diameter of 18 mm, wall thickness of 1.2 mm and the total length of 100 mm. The heat pipe was tested with tilt angle of horizontal degree and favorite angle 10 degree, with evaporator lower position to provide stable operation of the heat pipe. Input thermal load was varied from 40 W, with increment of 40 W, to above 100 W until the maximum temperature of the heat pipe wall reached 200$^{\circ}C$. Test results of the PCM heat pipe were presented in comparison with conventional heat pipe of the same basic dimensions. The performance was analyzed in terms of temperature distribution, thermal resistance and heat transport capability.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2226-2229
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• 2003

A new method is presented to construct a classifier. This was accomplished by combining a generalized regression neural network (GRNN) and a genetic algorithm (GA). The classifier constructed in this way is referred to as a GA-GRNN. The GA played a role of controlling training factors simultaneously. In GA optimization, neuron spreads were represented in a chromosome. The proposed optimization method was applied to a data set, consisted of 4 different promoter sequences. The training and test data were composed of 115 and 58 sequence patterns, respectively. The range of neuron spreads was experimentally varied from 0.4 to 1.4 with an increment of 0.1. The GA-GRNN was compared to a conventional GRNN. The classifier performance was investigated in terms of the classification sensitivity and prediction accuracy. The GA-GRNN significantly improved the total classification sensitivity compared to the conventional GRNN. Also, the GA-GRNN demonstrated an improvement of about 10.1% in the total prediction accuracy. As a result, the proposed GA-GRNN illustrated improved classification sensitivity and prediction accuracy over the conventional GRNN.

• Journal of Forest and Environmental Science
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• v.28 no.3
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• pp.144-151
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• 2012

Deforestation is a major and very critical problem faced by many tropical countries including Malaysia. Sabah is the second largest state in Malaysia and its deforestation rate has been accelerating. This study was conducted to monitor the deforestation in Sabah in the last two decades with Landsat images of 1990, 2000 and 2008. Supervised classification with maximum likelihood algorithm was conducted using the Landsat data for monitoring deforestation. In total, between 1990 and 2008, Sabah lost half of its intact forest, or more than 1.85 million ha in less than two decades. Overall, the deforestation rate for all forest types combined for the last two decades was 1.6% per year. Deforestation seemed to be accelerating because the deforestation rate between 1990 and 2000 was 0.9% per year and it had increased to 2.7% per year between 2000 and 2008. The deforestation trend seemed to follow a negative exponential from 1990 to 2008. In contrast, the agricultural areas increased rapidly with a total of increment more than 1 million ha. This confirmed that agriculture especially establishment of commercial plantation was the major factor of deforestation in Sabah for the last two decades.

• The Korean Journal of Ecology
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• v.18 no.2
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• pp.243-253
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• 1995

Seral changes in environmental factors and recovery of soil fertility during abandoned field succession after shifting cultivation were investigated in eastern Kangwon-Do, Korea. Relative light intensity of herb and shrub layer decreased gradually until 50 years and increased slightly thereafter. Amount of litter and nutrients derived from it were depicted as a parabola form showing the gradual increment during the first 50 years and slight decrease thereafter. Organic matter, pH value, total-N and Mg of soil were plotted as an early depletion-mid pinnacle form showing the extrems depletion during the first 10 years, abrupt increase in about 20 or 50 years and gradual decrease thereafter. Ca, Al, Mn and Na of soil were depicted as a pinnacle form showing the peak in about 20 or 50 years. Thickness and field capacity of soil increased gradually, but K and total-P did not show any tendency as succession proceeded. The soil fertility, overall capacity of soil nutrients and water for plant growth, was plotted as the early depletion-mid pinnacle form.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.4
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• pp.94-102
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• 1998

This paper aims at developing the prediction technique of the deformation for the embankment such as sea dike and shore protection relevant to reclamation project along the southern coast of the Korean Peninsula. Generally total deformation of a sea dike over clayey foundation are composed of immediate settlement, plastic deformation and consolidation settlement. Plastic deformation occurs when the ultimate bearing capacity is less than overburden pressure containing the stress increment due to the construction of an embankment. The reliable prediction of total settlement is very important since deformed final geometry of sea dike is directly connected for analysing the safety of the long-term slope failure and piping. During this study, plastic deformation, major part of deformation was analysed using the program developed by authors, whereas immediate settlement and consolidation settlement were predicted by Mochinaka and Sena's method and Terzaghi's 1-dimensional theory of consolidation respectively. In order to validate the prediction technique for the deformation, a case study of Koheung Bay reclamation works was carried out. A good agreement was obtained between observation and prediction, which means the applicability of the technique.

• The Korean Nurse
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• v.36 no.4
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• pp.100-109
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• 1997

This study examined effect of preceptorship on clinical education of 39 senior nursing students. Competency scores and satisfaction with preceptors scores were investigated. Competency scores of the students before the clinical education (pre-competency scores) were compared with the competency scores after the clinical education (post-competency scores), and satisfactory scores were also examined after the clinical education. Study results showed that the total post-competency scores were increased compared to the total pre-competency scores, and this increment was statistically significant. However, analyzing sub-domains of the competency scores indicated only the nursing-skill domain scores were increased while the scores of interpersonal domain and management domain were increased but statistically insignificant. Satisfaction with preceptors scores were also more than the average scores reflecting the students were satisfied with their preceptors generally. The students, However, grade low in the preceptors' intellectual ability while their professional and interpersonal ability were rather satisfied. This study indicated preceptors should make more efforts to teach interpersonal and management skill and increase their intellectual ability. This study recommended a systematic reward system for the preceptors to increase the motivation to teach students is needed.