• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.260-270
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• 1996

Structure and dynamics of Pinus densiflora community in Mt. Kaya were studied to provide the information needed for management of Pinus densiflora forest in the southern inland of Korea. Stratification structure of Pinus densiflora community in the lower and middle slope consisted of tree layer(10~15m), subtree layer(4~10m), shrub layer(1~4m), and herb layer(below 1m), while in the rock zone of ridge and top area consisted of tree layer(7~10m), subtree layer(2~7m), shrub layer(1~2m), and herb layer(below 1m). According to the diameter distribution of tree species in Pinus densiflora community, secondary Pinus densiflora forest will gradually decline. Its forest may be replaced by Quercus mongolica, Quercus serrata, Carpinus laxiflora, C. cordata, and Fraxinus rhychophylla in the lower slope, and by Quercus mongolica in the middle slope. Pinus densiflora forest has its seedlings and saplings in ridge and top area, so it may be sustained. By taking cores from Pinus densiflora trees in research area, it could be obtained that in the lower and middle slope, age of Pinus densiflora forest was about 80~90 years old. When the age of its trees was about 72~80 years old, withering trees of standing dead occurred. Disturbance regime of Pinus densiflora community in Mt. Kaya consisted of standing dead, uprooting and limbfall, these were 70.6%, 17.6% and 11.8% respectively. It takes about 100~110 years for advance growth of Pinus densiflora in ridge and top area to reach tree layer. During the period, it has twice chances of disturbance in standing dead. Annual diameter growth of Pinus densiflora was 2.45~2.9mm in the lower and middle slope, while it was 1.75mm in ridge and top region, by measuring cores.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.295-303
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• 2014

This study has tried to find the gap of health promoting behavior and the lower level-health responsibility, physical activity, self-actualization, stress management and self-efficacy-between new freshmen and other university students in dormitories who have taken health education as an elective course through health education. With 105 students conducted self-answering survey. It was conducted from June 12 to June 13 of the year 2013. Analysis has been conducted into 5-point scale in every parts of health promoting behavior, 4-point scale in self-efficacy. As a result of the study, after health education, the increasing level of the score was bigger than general university students in preceding research before education; from this, we could interpret that the peers who live together lead positive competition. For before-and-after affects of education, after-education score increased statistically significantly higher from before-education score for both freshmen and other students on every item of the survey. Especially, self-efficacy and stress management, which are the lower level of health promoting behavior, have shown statistic significance of health education. When comparing freshmen and other students, the item that showed significant difference was 'self-efficacy,' and for both before and after health education, other students had higher score than freshmen. Based on the result of the analysis, for those who live together with group of people such as in-dorm students, group education is preferred to personal education; in addition, when selecting health education recipients, better achievement of education will be expected by primarily educating students who have lower level of self-efficacy and stress, especially freshmen who have lower self-efficacy level than other students in university.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.3
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• pp.40-46
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• 2001

In this paper, a novel low power full adder circuit comprising only 10 transistors is proposed. The circuit is based on the six -transistor CMOS XOR circuit, which generates both XOR and XNOR signals and pass transistors. This adder circuit provides a good low power characteristics due to the smaller number of transistors and the elimination of short circuit current paths. Layouts have been carried out using a 0.65 ${\mu}m$ ASIC design rule for evaluation purposes. The physical design has been evaluated using HSPICE at 25MHz to 50MHz. The proposed circuit has been used to build 2bit and 8bit ripple carry adders, which are used for evaluation of power consumption, time delay and rise and fall time. The proposed circuit shows substantially improved power consumption characteristics, about 70% lower than transmission gate full adder (TFA), and 60% lower than a design using 14 transistors (TR14). Delay and signal rise and fall time are also far shorter than other conventional designs such as TFA and TR14.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.8
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• pp.1-6
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• 2010

We report on the electrical properties of Ti/Al/Ni/Au (20 nm/ 150 nm/ 30 nm/ 100 nm) Ohmic contacts and the anisotropic conductivity of n-type ${\alpha}$-plane ([11-20]) GaN grown on $\gamma$-plane ([1-102]) sapphire substrates. The Ti/Al/Ni/Au Ohmic contacts and their sheet resistances are characterized by using the transfer length method (TLM) as a function of azimuthal angles. It is found that the specific contact resistance does not depend on the axis orientation and there are significant electrical anisotropy in ${\alpha}$-plane GaN films on $\gamma$-plane sapphire substrates, and the sheet resistance varies with azimuthal angles. The sheet resistance values in the direction parallel to m-axis [1-100] are 25% ~ 75% lower than those parallel to c-axis [0001] directions. Thus, Basal stacking faults (BSFs) are offered as a feasible source of the anisotropic mobility in defected m-axis direction because the band-edge discontinuities owing to the differential band gap structure.

• Korean Journal of Social Welfare
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• v.52
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• pp.89-115
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• 2003

While many social work studies has focused on the development of practice intervention and demonstration of the efficacy, little attention has been given to the way how the results can be disseminated and utilized in practice area. But attempts to bridge the research-practice gap empathize importance of dissemination and utilization including knowledge utilization, innovation diffusion, information dissemination, program replication, and technology transfer etc. In this recognition, this study that focused on the process after development of program tried to search and analyze the real disseminating process and utilization state with applying Growing-up Skills Program(GUSP) developed and disseminated by this researcher. For the purpose, theories and models for program diffusion were reviewed, and dissemination & utilization of GUSP was analyzed on the 'Herie & Martin's model' with retrospective perspectives. Through this tracer study, these were confirmed or founded as problems of GUSP in disseminating process : lack of specific strategy for the dissemination ; unplanned coping due to little preparation ; and unclear and insufficient understanding of the target system in the beginning stage of dissemination. And followings are suggested for the improvement of social work program dissemination & utilization in the field: to conduct diffusion process on the basis of a proper model; to consider integrative relationship between D&D and dissemination & utilization ; to endeavor for collecting feed back from the field ; and to reinforce social work education and study related to innovation diffusion. These results showed importance of dissemination & utilization in social work and utility of GUSP despite of several limitations. More concerns of dissemination & utilization are needed for the integration of research and practice in Korean social work.

• Journal of the Korean Geographical Society
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• v.48 no.6
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• pp.879-896
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• 2013

The assessed land values and housing prices have been widely utilized as a basic information for the land and house trades and for evaluating governmental and local taxes. However, there exists a price difference in actual markets between the assessment level and assessed land values or housing prices. This paper emphasizes the spatial mismatch between the assessed land values and housing market prices and particularly addresses the following two aspects by focusing on spatial effects of the modifiable areal units, which would substantially affect the estimation of the assessed land values and housing prices. First, we examine the spatial distributions of the assessed land values and housing market prices, and the gap between those prices, on the basis of the aggregated spatial units(i.e., aggregation districts). Second, we explore the scale effect of the MAUP(modifiable areal unit problem) generally embedded in estimating the prices of the sampled standard lands and houses, and calibrating the correction index for the land values and housing prices for the individuals. For the application, we analysed the land values and housing prices in Seoul utilizing GIS and statistical software. As a result, some spatial clusters that the housing market prices are significantly higher than the assessed land values were identified at a finer geographic level. Also, it was empirically revealed that the statistical results from the regression of regional variables on the assessed land values for the individuals are significantly affected by the aggregation levels of the spatial units.

• Korean Journal of Health Education and Promotion
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• v.17 no.2
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• pp.17-33
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• 2000

The aim of this study is having the status, knowledge and attitude of the high school attendees toward smoking be analyzed, helping to make effective health education methods to diminish adolescent smoking habits. The field self-questionnaire investigation has been performed from Oct 10th through 23rd in 1999. The whole 427 cases were distributed to 1st and 2nd grade students of randomly selected men's high school in Seoul. And 414 cases (97%) were finally selected for analysis after exclusion of cases with insufficient information. The main contents of questionnaire are composed of several sectors; the general characteristics of the interviewees, the relationship with parents, the life style and the peer relationship in school. And smoking-related characteristics are taken into consideration, too. The major findings of the study are as follows: The smoking/non-smoking related factors are, in socio-demographical terms, the grade, average spending per month of the interviewees. And the degree of satisfactory relationship with parents is significant on smoking behavior. The higher, the degree of satisfaction on school life and relationship with designated teacher, the more chances of non-smoking habit. Poor academic grades and peer group dependability of interviewees cause higher smoking habit rate in other way. The self-interviewees grade and cohabitation with parents are also significant on both the attitude toward smoking habit and the knowledge on smoking statistically. The academic history and vocations of the parents and the academic grades of interviewees are also effective variables, but don't make any gap between groups knowledge on smoking. Smoking groups used to have positive attitude toward smoking habit. Both the attitude and knowledge on smoking by the consideration of Quit-smoking have statistically significance. The groups which have negative attitude and high knowledge on smoking quit-smoking into consideration. And the primary cause of quit-smoking is on health by smoking. Depression, stress, adult smoking in the house, peer group pressure, cigarettes advertisements on papers and magazines and smoking scenes on TV have positive correlation on forming smoking habit (p〈0.001) But the knowledge on diseases triggered by smoking has negative correlation on forming smoking habit. (p〈0.05, p〈0.001). Social factors as monthly spending, relationship and communication with parents, the degree of satisfaction in school life, academic grades and student-teacher relationship have crucial negative correlation on smoking habit. That is to say, the higher, the monthly spending is, the worse, the relationship with parents and teachers is, the lower, the academic grades of the student is, the percentage of the interviewees who have smoking habit seems to get higher.

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.133-133
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• 2002

Purpose： The purpose of paper is to implement software to visualize brain fiber tract using a 24-bit color coding scheme and to test its feasibility. Materials and Methods： MR imaging was performed on GE 1.5 T Signa scanner. For diffusion tensor image, we used a single shot spin-echo EPI sequence with 7 non-colinear pulsed-field gradient directions： (x, y, z)：(1,1,0),(-1,1,0),(1,0,1),(-1,0,1),(0,1,1),(0,1,-1) and without diffusion gradient. B-factor was 500 sec/$\textrm{mm}^2$. Acquisition parameters are as follows： TUTE=10000ms/99ms, FOV=240mm, matrix=128${\times}$128, slice thickness/gap=6mm/0mm, total slice number=30. Subjects consisted of 10 normal young volunteers (age：21∼26 yrs, 5 men, 5 women). All DTI images were smoothed with Gaussian kernel with the FWHM of 2 pixels. Color coding schemes for visualization of directional information was as follows. HSV(Hue, Saturation, Value) color system is appropriate for assigning RGB(Red, Green, and Blue) value for every different directions because of its volumetric directional expression. Each of HSV are assigned due to (r,$\theta$,${\Phi}$) in spherical coordinate. HSV calculated by this way can be transformed into RGB color system by general HSV to RGB conversion formula. Symmetry schemes： It is natural to code the antipodal direction to be same color(antipodal symmetry). So even with no symmetry scheme, the antipodal symmetry must be included. With no symmetry scheme, we can assign every different colors for every different orientation.(H =${\Phi}$, S=2$\theta$/$\pi$, V=λw, where λw is anisotropy). But that may assign very discontinuous color even between adjacent yokels. On the other hand, Full symmetry or absolute value scheme includes symmetry for 180$^{\circ}$ rotation about xy-plane of color coordinate (rotational symmetry) and for both hemisphere (mirror symmetry). In absolute value scheme, each of RGB value can be expressed as follows. R=λw｜Vx｜, G=λw｜Vy｜, B=λw｜Vz｜, where (Vx, Vy, Vz) is eigenvector corresponding to the largest eigenvalue of diffusion tensor. With applying full symmetry or absolute value scheme, we can get more continuous color coding at the expense of coding same color for symmetric direction. For better visualization of fiber tract directions, Gamma and brightness correction had done. All of these implementations were done on the IDL 5.4 platform.

• Journal of Digital Convergence
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• v.17 no.12
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• pp.45-57
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• 2019

The digital economy has created a new platform-based business model and raised the issue of the international taxation system in line with rapid economic development. Voices of fair taxation have also grown due to tax breaks to countries with low tax rates, problems caused by the gap between traditional and digital companies, and problems of business-oriented taxation systems. As a result, the international movement to lay the foundation for the international taxation system based on the business model suitable for the digital economy has become active. The stances of foreign organizations and countries are different, and the necessity of domestic policy introduction is increasing when cooperation at the international level is needed. This study was conducted to analyze the policy network and to help decision making. The results of the study showed that there were differences among domestic stakeholders depending on the actors. The EU suggested SDP in the long term, Digital Service Tax in the short term, and OECD suggested SEP in the long term. It was found that a careful approach to decision making and an in-depth study of the policy process are necessary.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.2
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• pp.15-20
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• 2010

In this study, AZO (Al: 3 wt%) thin films have been prepared on PES Plastic substrates at various working pressure (5~20 mTorr), $O_2$ gas flow rate(0~3%) and the fixed substrate temperature of 200 f by using the RF magnetron sputtering and their optical and electrical properties have been studied. The XRD measurement shows that AZO thin films exhibit c-axis preferred orientation. From the results of AFM measurements, it is known that the lowest surface roughness (3.49 nm) is obtained for the AZO thin film fabricated at 5 mTorr of working pressure and 3% of $O_2$ gas flow rate. The optical transmittance of AZO thin films is measured as 80% in the visible region. We observe that the energy band gap of AZO thin films increases with decreasing the working pressure and the $O_2$ gas flow rate. This phenomenon is due to the Burstein-Moss effect. Hall measurement shows that the maximum carrier concentration ($2.63\;{\times}\;10^{20}\;cm^{-3}$) and the minimum resistivity ($4.35\;{\times}\;10^{-3}\;{\Omega}cm$) are obtained for the AZO thin film fabricated at 5mTorr of working pressure and 0% of $O_2$ gas flow rate.