• Journal of Environmental Science International
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• v.19 no.11
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• pp.1337-1353
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• 2010

This study intended to investigate environmental factors including soil and vegetation in order to understand the environmental and ecological characteristics of 12 different habitats of Iris odaesanensis. These habitats, according to investigations, are mostly located at elevation of 280 m to 1,555 m with angles of inclination ranging from 2 degree to 30 degrees. A total of 273 vascular plants are identified in 23 quadrates of 12 habitats. Dominant species of woody plants in 12 habitats are represented as Quercus mongolica in the tree layer (T1) and the subtree (T2) layer, and Lespedeza maximowiczii, Lindera obtusiloba, Rhododendron schlippenbachii in the shrub (S) layer. The importance value of Iris odaesanensis is 9.65%, as regards the herbaceous layer, and 6 highly ranked species such as Carex siderosticta (3.92%), Meehania urticifolia (2.67%), Spodiopogon cotulifer (2.58%), Aconitum pseudolaeve (2.51%), Carex bostrychostigma (2.28%) and Disporum smilacinum (2.09%) are considered to be an affinity with Iris odaesanensis in their habitats. The degree of their average species diversity is 1.32, and that of dominance and evenness are 0.08 and 0.89, respectively. The type of soil is sandy loam and loam, and the average field capacity of soil is 28.31%. Their average organic matter is 16.71%, soil pH 5.29, and available phosphorus is 9.29%. Correlation coefficients analysis based on environmental factors, vegetation and soil analysis shows that the coverage of Iris odaesanensis is correlated with pH and dominance, and species richness is positive related with species diversity.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1452-1457
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• 2004

In this paper, a method of measuring the length of defects on the wall and restructuring the defect image is proposed based on the estimation algorithm of a camera orientation which uses the declination angle of a laser slit beam. The estimation algorithm of the horizontally inclined angle of CCD camera adopts a 3-dimensional coordinate transformation of the image plane where both the laser beam and the original image of the defects exist. The estimation equation is obtained by using the information of the beam projected on the wall and the parameters of this equation are experimentally obtained. With this algorithm, the original image of the defect can be reconstructed to an image normal to the wall. From the result of a series of experiments, the measuring accuracy of the defect is measured within 0.5% error bound of real defect size under 30 degree of the horizontally inclined angle. The proposed algorithm provides the method of reconstructing the image taken at any arbitrary horizontally inclined angle to the image normal to the wall and thus, it enables the accurate measurement of the defect lengths only by using a single camera and a laser slit beam.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.2
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• pp.153-162
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• 1997

In this study, the wet surface heat transfer coefficients and friction factors of the heat exchanger with slit-wavy fin were measured. Four sample cores of two or three row with fins of 12 fpi or 16 fpi were tested. Tests were conducted in a closed loop wind tunnel, where the heat exchanger was mounted at 45 degree inclination angle. The wet surface heat transfer coefficient was reduced following the procedure given in ARI 420-81. During the course, new definitions of the $\varepsilon$-NTU applicable to enthalpy driving system were introduced. The wet surface heat transfer coefficients were approximately equal to the dry surface values. However, the friction factors were approximately 120% to 170% higher than those of the dry surface. Both the heat transfer coefficient and the friction factor of the wet surface increased as the relative humidity increased, fin pitch decreased, and the number of row decreased, although the difference was not large.

• Journal of Korean Neurosurgical Society
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• v.56 no.5
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• pp.400-404
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• 2014

Objective : Clip artifacts limit the visualization of intracranial structures in CT scans from patients after aneurysmal clipping with cobalt alloy clips. This study is to analyze the parameters influencing the degree of clip artifacts. Methods : Postoperative CT scans of 60 patients with straight cobalt alloy-clipped aneurysms were analyzed for the maximal diameter of white artifacts and the angle and number of streak artifacts in axial images, and the maximal diameter of artifacts in three-dimensional (3-D) volume-rendered images. The correlation coefficient (CC) was determined between each clip artifact type and the clip blade length and clip orientation to the CT scan (angle a, lateral clip inclination in axial images; angle b, clip gradient to scan plane in lateral scout images). Results : Angle b correlated negatively with white artifacts (r=-0.589, p<0.001) and positively with the angle (r=0.636, p<0.001) and number (r=0.505, p<0.001) of streak artifacts. Artifacts in 3-D images correlated with clip blade length (r=0.454, p=0.004). Multiple linear regression analysis revealed that angle b was the major parameter influencing white artifacts and the angle and number of streak artifacts in axial images (p<0.001), whereas clip blade length was a major factor in 3-D images (p=0.034). Conclusion : Use of a clip orientation perpendicular to the scan gantry angle decreased the amount of white artifacts and allowed better visualization of the clip site.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.111-115
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• 2016

Background: The scattered photons cause reduction of the contrast of radiographic image and it results in the degradation of the quality of the image. In order to acquire better quality image, an anti-scattering x-ray gird should be equipped in radiography system. Materials and Methods: The X-ray anti-scattering grid of the inclined type based on the hybrid concept for that of parallel and focused type was tested by MCNP code. The MCNPX 2.7.0 was used for the simulation based test. The geometry for the test was based on the IEC 60627 which was an international standard for diagnostic X-ray imaging equipment-Characteristics of general purpose and mammographic anti-scatter grids. Results and Discussion: The performance of grids with four inclined shielding material types was compared with that of the parallel type. The grid with completely tapered type the best performance where there were little performance difference according to the degree of inclination. Conclusion: It was shown that the grid of inclined type had better performance than that of parallel one.

• The Journal of Korean Association of Computer Education
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• v.10 no.4
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• pp.27-37
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• 2007

Recently, robot programming education are suggested for elementary students. However, the degree of class participation of female students was low because of the failure of the recognition of female students' inclination when they chose contents and instructional strategies. Thus, this paper analyzed the gender differences of interests of elementary students have in robot programming through questionnaire and suggested the robot programming instructional strategies considered gender differences through reviewing literature in such areas as gender differences in computer learning and programming learning, and effective instructional strategies. Furthermore, the validity of the instructional strategies which are suggested was verified by experts. Through this research, the researcher expects for the researcher findings to be bases for a more active participation of female students in computer field.

• Tunnel and Underground Space
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• v.1 no.2
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• pp.181-203
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• 1991

The effects of geologic structures such as rock joins and bedding planes on the thermal conductivity of a discontinuous rock mass are studied. The expressions for the equivalent thermal conductivities of jointed rock masses are derived and found to be anisotropic. The degree of anisotropy depends primarily on the thermal properties contrast between the joint phase and surrounding intact rock, the joint density expressed as volume fraction and the inclination angle of the joint. Within the context of 2-dimensional finite element heat transfer scheme, the isotherms around a circular hole are analyzed for both the isotropic and anisotropic rock masses in 3 different thermal boundary conditions. i.e. temperature, heat flux and convection boundary conditions. The temperature in the stratified anisotripic rock mass is greatly influenced by the thermal properties of the rock formation in contact with the heat source. Using the excavation-temperature coupled elastic plastic finite element method, analyzed is the thermo-mechanical stability of a circular opening subjected to 10$0^{\circ}C$ at a depth of 527m. It is found that the thermal stress concentration was enough to deteriorate the stability and form a plastic yield zone around the opening, in contrast to the safety factor greater than 2 resulted form the excavation-only analysis.

• Physical Therapy Korea
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• v.6 no.3
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• pp.51-58
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• 1999

In general, sitting balance is decreased in subjects with spinal cord injury. The purpose of this study was to evaluate the inter- and intra-rater reliability of the Functional Reach Test (FRT) which is used to measure sitting balance. The subjects of this study were 26 persons with spinal cord injury, and they were divided into three groups according to their injury level. Group I, II and III consisted of the following $C_5{\sim}C_8$ quadriplegics, $T_1{\sim}T_4$, and $T_9{\sim}T_12$ paraplegics, respectively. Subjects sat on a mat table that was set at an 80 degree inclination. During three sessions, the length subjects could reach in the FRT test was measured by three physical therapists, and compared to each other. The results showed that intraclass correlation coefficients (2,1) were above 0.97 and inter-rater difference was not statistically significant. The one-way ANOVA demonstrated that reach differed between groups with lower thoracic lesion and the other test groups. In conclusion, we think modified FRT is useful and reliable method to measure the sitting balance in subjects with spinal cord injury.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.1
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• pp.37-45
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• 2002

A method of measuring the length of defects on the wall and restructuring the defect image is proposed based on the estimation algorithm of a camera orientation, which uses the declination angle of a laser slit beam. The estimation algorithm of the horizontally inclined angle of CCD camera adopts a 3-dimensional coordinate transformation of the image plane where both the laser beam and the original image of the defects exist. The estimation equation is obtained by using the information of the beam projected on the wall and the parameters of this equation are experimentally obtained. With this algorithm, the original image of the defect can be reconstructed as an image normal to the wall. From the result of a series of experiments, the measuring accuracy of the defect is measured within 0.5% error bound of real defect size under 30 degree of the horizontally inclined angle. The proposed algorithm provides the method of reconstructing the image taken at any arbitrary horizontally inclined angle as the image normal as the wall and thus, it enables the accurate measurement of the defect lengths by using a single camera and a laser slit beam.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.381-385
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• 1997

A long-term prediction algorithm of geostationary orbit was developed using the analytical method. The perturbation force models include geopotential upto fifth order and degree and luni-solar gravitation, and solar radiation pressure. All of the perturbation effects were analyzed by secular variations, short-period variations, and long-period variations for equinoctial elements such as the semi-major axis, eccentricity vector, inclination vector, and mean longitude of the satellite. Result of the analytical orbit propagator was compared with that of the cowell orbit propagator for the KOREASAT. The comparison indicated that the analytical solution could predict the semi-major axis with an accuracy of better than $pm35$ meters over a period of 3 month.