• Ecology and Resilient Infrastructure
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• v.7 no.2
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• pp.90-96
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• 2020

Recently, a method that applies laser scanning (LS) that acquires vegetation information such as the vegetation habitat area and the size of vegetation in a point cloud format has been proposed. When LS is used to investigate the physical shape of vegetation, it has the advantage of more accurate and rapid information acquisition. However, to examine uncertainties that may arise during measurement or post-processing, the process of adjusting the data by the actual data is necessary. Therefore, in this study, the physical structure of stems, branches, and leaves of woody vegetation in an artificially formed river channel was manually investigated. The obtained results then compared with the information acquired using the three-dimensional terrestrial laser scanning (3D TLS) method, which repeatedly scanned the target vegetation in various directions to obtain relevant information with improved precision. The analysis demonstrated a negligible difference between the measurements for the diameters of vegetation and the length of stems; however, in the case of branch length measurement, a relatively more significant difference was observed. It is because the implementation of point cloud information limits the precise differentiation between branches and leaves in the canopy area.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.2
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• pp.252-262
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• 1994

As a means to get a better understanding of the kind of form changes to which is subject the neck of the men, in its aging process, several measurement recordings on a vertical and horizontal sections were carried. Subjects were young, middle aged and elder men (15 in their twenties, 11 in their forties and again 11 in their sixties) 1) The analysis of the meansurement results led us to distinguish 3 types of subjects according to the position of the their Adam's apple with regard to the horizontal plane containing their 7th cervical vertebrae point : clearly above (Type I), next to(Type II), clearly below(Type III). We found that young men correspond to the Type I and II, middle aged men to the Type ll and 111 and elder men only to the Type III. 2) The comparison of the horizontal sectional surface contained in the planes corresponding to the 4 points, shows a larger sectional surface for elder men in the Adam's apple plane, accompanied by a change of position of the Adam's apple forwards. As for the front neck point plane, the body sectiolial surface is larger in depth in elder men, without much change in breadth. And for the acromion point plane, we observed also an increase in depth, but with a decrease in breadth corresponding partially to the atrophy of the thoraric cage in eldermen.

• Journal of Elementary Mathematics Education in Korea
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• v.15 no.1
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• pp.57-75
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• 2011

This research aimed to explore the effects of collaborative writing activities in a mathematical context, specifically pertaining to areas such as numbers and operation, geometrical figure, and measurement in Mathematics: Level 5-b, on their mathematical achievement gain and disposition among Grade 5 students. To do this, out of a total of 62 students selected from two Grade 5 classes of J Elementary School in Dalseo-gu, Daegu City, who were found to be homogenic from the tests of math performance and dispositions, an experimental group(n=31) was designed and compared to a control group (n=31). Over a six week period from October to November in 2009, the experimental group was given collaborative writing lessons in math classes while the control group was given teacher-oriented regular lessons. The results were as follows. First, there was more or less considerable, though not significant, difference in overall mathematical achievement in the students experiencing collaborative writing activities when compared with the students in the control group. However, in terms of numbers and operation, a sub-category of mathematics, there was significant difference between the two groups. Second, the students experiencing collaborative writing activities were more positively affected in all sub-categories of mathematical disposition: confidence, flexibility, determination, curiosity, reflection, and value, than those in the control group. In summing up, the exposure of collaborative writing activities to mathematics learning was found to help students not only to have a concrete and proper grasp of the relevant problem solving process, which was observed from their mathematical achievement gain especially in the sphere of numbers and operation, but also to have their mathematical disposition set towards more positive direction, which was seen in all sub-categories of mathematical disposition measurement.

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.35-40
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• 2008

A distillation tower is one of the important facilities which separates and refines a crude oil stream according to certain boiling points. Its operation efficiency can affect the productivity of a refinery substantially. The objective of this study is to elucidate some operational information on the internal conditions of a distillation tower from a measurement of density profile by using a sealed gamma-ray source and a radiation detector. Gamma radiation counts were measured by a BGO detector positioned diametrically outside the tower-wall, opposite to the gamma source(Co-60) as the detector and the source were lowered concurrently. From the results, structural abnormality of the trays was not found inside the tower. Considering the flow distribution patterns, however, a vapor phase was dominantly formed at the upper part of the tower and a liquid phase at the lower part. From the gamma scanning of the distillation tower, it is anticipated that the gamma absorption technique can be used as an important tool for confirming the structural soundness of trays and investigating flow distribution in refinery facilities.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.71-80
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• 1992

The Seakeeping committee of Korea Towing Tank Conference executed the cooperative experimental study on deck wetting phenomena using S-175 contatiner model ships. Two members, Korea Research Institute of Ships and Ocean Engineering(KRISO) and Hyundai Maritime Research Institute(HMRI) participated in the study. This study was initiated by the ITTC(International Towing Tank Conference) Seakeeping Committee as the cooperative study of the 19th ITTC aiming at the establishement of the model test procedure on the deck wetting phenomena. Special emphasis was made on the determination of reliable record length for experimental measurement on rarely occurring events(such as deck wetness, slamming etc). Comparisons were made on both the test results and the test procedrues in this research. The measured frequencies of deck wetting show remarkable deviations between the runs. This fart implies that sufficiently long record length is required in the deck wetness measurement compared to the conventional ship motion tests. Careful considerations were made on the physical interpretation of the deck wetting phenomena, the correlation between the measured relative motion at stemhead and the measured deck wetness, and the estimation of deck wetting frequencies by Poisson process.

• Journal of Adhesion and Interface
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• v.2 no.1
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• pp.9-17
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• 2001

Curing behavior and interfacial properties were evaluated using electrical resistance measurement and tensile/compressive fragmentation test. Electrical resistivity difference (${\Delta}R$) during curing process was not observed in a bare carbon fiber. On the other hand, ${\Delta}R$ appeared due to the matrix contraction in single-carbon fiber/epoxy composite. Logarithmic electrical resistivity of the untreated single-carbon fiber composite increased suddenly to the infinity when the fiber fracture occurred under tensile loading, whereas that of the ED composite reached relatively broadly up to the infinity. Comparing to the untreated case, interfacial shear strength (IFSS) of the ED treated composite increased significantly in both tensile fragmentation and compressive Broutman test. Microfailure modes of the untreated and the ED treated fiber composite showed the debonding and the cone shapes in tensile test, respectively. For compressive test, fractures of diagonal slippage were observed in both untreated and the ED treated composite. Sharp-end shape fractures exhibited in the untreated composite, whereas relatively dull fractures showed in the ED Heated composite. It is proved that ED treatments affected differently on the interfacial adhesion and microfailure mechanism under tensile/compressive tests.

• Journal of Korea Technology Innovation Society
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• v.13 no.4
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• pp.638-655
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• 2010

The importance of international science and technology cooperation is growing more and more, but we do not know much about what criteria could be used to choose a science or a technology that needs international cooperation first and foremost among many kinds of competing sciences and technologies. Moreover, this selection process is affected by evaluators' or science/technology experts' perception, but we do not quite know what they actually see when they evaluate the needs of international cooperation. This study investigates the conditions that international science and technology cooperation is encouraged by scholars and researchers in various areas. Based on theoretical arguments of Transaction Cost Economics, Measurement View, and Knowledge-Based View, we drew hypotheses on when experts perceive greater needs of international cooperation. Using the classification categories of 10 major sciences and technologies, we collected data from 151 respondents from scientists in research institutions and colleges. As a result, we found that experts in science and technology areas perceive strong needs of international cooperation when the importance of focal science or technology is high and the relative national level of focal science or technology is low. Also, we found that the importance and relative level of focal science and technology have positive moderating effects each other. Lastly, we found that when experts evaluate their own major areas, the strength of positive relationship between the importance of science and technology and needs of international cooperation is diminished.

• Spatial Information Research
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• v.23 no.5
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• pp.31-40
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• 2015

The purpose of this paper is to propose a data transformation method for visualizing the statistical information based on the grid system which has regular shape and size. Grid is better solution than administrator boundary or census block to check the distribution of the statistical information and be able to use as a spatial unit on the map flexibly. On the other hand, we need the additional process to convert the various statistical information to grid if we use the current method which is areal interpolation. Therefore, this paper proposes the 3 steps to convert the various statistical information to grid. 1)Geocoding the statistical information, 2)Converting the spatial information through the defining the spatial relationship, 3)Attribute transformation considering the data scale measurement. This method applies to the population density of Seoul to convert to the grid. Especially, spatial autocorrelation is performed to check the consistency of grid display if the reference data is different for same statistic information. As a result, both distribution of grid are similar to each other when the population density data which is represented by census block and building is converted to grid. Through the result of implementation, it is demonstrated to be able to perform the consistent data conversion based on the proposed method.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1375-1387
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• 2016

The purpose of this study was to evaluate the effect of exercise on cognitive function in the elderly through a systematic literature review and meta-analysis. For the study purpose, 14 studies were selected through a systematic process of using several databases and 11 studies were used to estimate the effect size of exercise on cognitive function. Meta-analysis was performed using a random effects model, and the effect size on cognitive function was calculated. The effect size for cognitive function of exercise intervention was Hedges' g=1.05 (95% CI: 0.61~1.50), indicating a large effect size. For heterogeneity, moderator analysis was performed using intervention, number of times per week, intervention duration, and cognitive function measurement. Cognitive function measurement was statistically significant, the other moderators did not significant difference. Results support that exercise has significant positive effects on cognitive function in elderly in korea. It also provided a basis that can be applied to exercise intervention design for cognitive function.

• Korean Journal of Health Education and Promotion
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• v.15 no.1
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• pp.179-194
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• 1998

This study focused on the body composition of Korean Basketball Players in Dual X -ray Absorptiometry. The principal subjects of this study were 10 Basketball Players who participated in the process of Dual Energy X -ray Absorptiometry at K.H. University Hospital for 8 months from Sept. 1. 1996 to April, 30. 1997. On the basis of the these measurements, the authors calculated physical indices and total fat percent. On the results of bone densitometry, the author analyzed body fat weight, body composition according to body position, bone mineral density and discerned the difference between the fatness which was calculated indirectly and which gained from the bone densitometry. 1. General Characteristics The mean age of the subjects was 20.4$\times$1.35 year. 2. Physical. Measurement The mean physical growth and development of the subjects were superior to standard value of the average Koreans 3. Body Fat by Physical Measurement Body surface area was 2.019$\times$0.111$m^2$, body volume was 74.4$\times$7.2$\ell$, body density was 1.041$\times$0.007$\ell$/kg, and body fat percent was 24.9$\times$2.9%. 4. Body Fat by Bone Densitometry Total body fat percent was 15.17$\times$2.19% and according to body position that of upper limb was 1.62%, that of lower limb was 5.55%, that of trunk was 7.06% and that of head was 1.05%. There was significant difference between the amounts of body fat from the methods used in this study; that from physical measurements and from bone densitometry method could be said most desirable. 5. Body composition According to Body Position Trunk was highest at 46.7%, lower limb was 36.0%, upper limb was 10.6%, and head was 6.7% in order. 6. Bone Mineral Content and Bone Density In bone mineral amount by body position, that of upper limb was 466.9$\times$46.4g, that of lower limb was 1,424.1$\times$154.0g, that of trunk was 1,343.0$\times$150.3g, and total bone mineral content was 3,786.8$\times$348.4g(4.78$\times$0.13%). Bone mineral density by body position, that of upper limb was 0.758$\times$0.072g/$\textrm{cm}^2$, that of lower limb was 1,342$\times$0.095g/$\textrm{cm}^2$, that of trunk was 1,169$\textrm{cm}^2$0.082g/$\textrm{cm}^2$, that of head was 1,742$\times$0.154g/$\textrm{cm}^2$ and total bone mineral density was 1,204$\times$0.077g/$\textrm{cm}^2$.