• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.82-89
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• 2004

To secure stability and availability of Rammed Aggregate Pier method as the foundation of a structure, the shear strength characteristics according to the area replacement ratio of RAP and the relative density of in-situ ground was studied through soil laboratory tests and large direct shear tests in a model ground. As a result, the internal friction angle tends to increase in proportion to in-situ relative density(Very Loose, Loose, Medium) in composite ground formed by the same area replacement ratio of RAP and also increase in proportion to increasing the area replacement ratio(30, 40, 50%) of RAP in the same ground condition. Furthermore, the comparative analysis between the experimental value and theoretical value of the shear strength is carried out.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.1
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• pp.161-173
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• 1999

This study was performed to compare the bone mineral densities measured at mandibular premolar area by copper-equivalent image and hydroxyapatite phantom with those measured at radius by dual energy absorptiometry and to evaluate the clinical usefulness of Digital system with slide scanner, copper-equivalent image, and hydroxyapatite phantom. For experiment. intraoral radiograms of 15 normal subjects ranged from 20 years old to 67 old were taken with copper-step wedge at mandibular premolar area and bone mineral densities calculated by conversion equation to bone mineral density of hydroxyapatite were compared with those measured at radius distal 1/3 area by Hologic QDR-1000. Obtained results as follows: 1) The conversion equation was Y=5.97X-0.25 and its determination coefficient was 0.9967. The coefficient of variation in the measurement of copper-equivalent value ranged from 4％ to 8％ and showed high reproducibility. 2) The coefficient of variation in the measurement of bone mineral density by the equation ranged from 7％ to 8％ and showed high reproducibility. 3) The bone mineral densities ranged from 0.35 to 0.79g/cm2 at mandibular premolararea. 4) The correlation coefficient between bone mineral densities at mandibular premolar area and those at radius distal 1/3 area was 0.8965. As summary, digital image analyzing system using copper-equivalent image and hydroxyapatite phantom appeared to be clinically useful to measure the bone mineral density at dental area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.5
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• pp.43-49
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• 2014

Fairy Pittas use the forest around the valley and Gotjawal as breeding places. This survey was conducted to investigate the characteristic of earthworms, specifically its population density, body size around the breeding site in Gotjawal and the forest around the valley areas from the middle of July to the end of July 2013. A total of 405 individual earthworms were collected in the 100 small established quadrats, in which 315 were found in Gotjawal and 90 were found in the forest around the valley area. The density of earthworms in Gotjawal was significantly higher compared to that forest around the valley area. It was also observed that the body size of earthworms was significantly different between Gotjawal and the forest around the valley area. Proportion of number of individuals which are larger than 7cm in body size was 43%(n=135) in Gotjawal and 84%(n=76) in the forest around the valley area, respectively. Soil area was not important factor to the density of earthworms. We suggest that Gotjawal can be considered as a suitable breeding site for Fairy Pitta because of the richness of its primary food in this area.

• Korean Journal of Community Nutrition
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• v.13 no.1
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• pp.125-133
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• 2008

This study was carried out to compare bone density risk factors affecting women's BMD, and to examine the relationship age, lifestyle and dietary habits for bone health by physical measurement and questionnaires. The subjects of this study were 194 women living in the Seoul area. When the subjects were divided into normal and risk groups, BMD, height, weight, BMI, total body water, soft lean mass, fat free mass, protein, mineral, body-fat of normal group were much higher than those of the risk group. The breakfast eating rate of the normal group was much higher than that of the risk group, walking time was significantly longer and exercise was more (p < 0.05). The normal group had more frequent intakes of tunas, squid, radishes, the green parts of radish, cucumbers, carrots and Iucchinis, tomatoes, and grapes than the risk group (p < 0.01 or p < 0.05). In conclusion, breakfast eating, exercise, intakes of some foods such as anchovies, radishes, carrots, zucchinis and tomatoes were significantly important factor to prevent bone density risk.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.4
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• pp.231-240
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• 2017

This paper aims to study a method to estimate precise carbon absorption by quantification of forest information that uses accurate LiDAR data, hyperspectral image. To estimate precise carbon absorption value by using spatial data, a problem was found out of carbon absorption value estimation method with statistical method, which is already existed method, and then offered optimized carbon absorption estimation method with spatial information by analyzing with methods of compare digital aerial photogrammetry and LiDAR data. It turned out possible Precise classification and quantification in case of using LiDAR and hyperspectral image. Various classification of tree species was possible with use of LiDAR and hyperspectral image. Classification of hyperspectral image was matched in general with field survey and Mahalanobis distance classification method. Precise forest resources could be extracted using high density LiDAR data. Compared with existing method, 19.7% in forest area, 19.2% in total carbon absorption, 0.9% in absorption per unit area of difference created, and improvement was found out to be estimated precisely in international code.

• Atmosphere
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• v.28 no.1
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• pp.1-13
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• 2018

Characteristics of wind resources of offshore and coastal regions were compared using wind data obtained from HeMOSU-1 (Herald of Meteorological and Oceanographic Special Unit-1) meteorological mast located at Southwestern Sea, and ground-based LiDAR (Light Detection And Ranging) at Gochang observation site near it. The analysis includes comparison of basic wind statistics such as mean wind speed, wind direction, power law exponent and their temporal variability as well as site assessment items for the wind power plant such as turbulence intensity and wind power density at the two observation sites. It was found that the wind at HeMOSU-1 site has lower diurnal and seasonal variability than that at Gochang site, which lead to smaller turbulence intensity. Overall, the results of the comparative analysis show that the wind resource at HeMOSU-1 site located offshore has more favorable condition for wind power generation than the wind resource at Gochang which shows nature of coastal area.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.41-47
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• 1972

Comparative study on dynamic change of canopy structure during ripening period were carried out by using newly bred high yield rice cultivar (IR 667-Suwon 213) and a commercial variety, Jinhung in relation to nitrogen nutrition. The results were as follows. 1. Canopy structure pattern (vertical distribution of dry matter density at heading)was vertical type for Jinhung and horizontal type for IR 667. 2. The vertical distribution pattern of leaf area density (or weight) in the canopy was central dominant type for IR 667 while apical dominant type for Jinhung. 3. Canopy conservation pattern and percent distribution pattern of leaf area density followed the vertical distribution pattern of leaf area density. 4. Canopy persistence was weaker in IR 667, thus they have smaller canopy conservation ratio indicating faster senescence. 5. Slow supply of nitrogen (sulfur coated urea) showed a trend to change the apical dominant pattern into the central dominant pattern by the conservation of central portion, and it-resulted in higher yield though nitrogen nutrition did little affect canopy pattern. 6. The central and apical dominant pattern appeared to be well matched to the upper leaf-dependent type and the lower leaf-dependent type of grain yield, respectively.

• International Journal of Contents
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• v.5 no.4
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• pp.35-39
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• 2009

The purpose of this study was to evaluate the changes in skeletal muscle architecture and qualitative properties by muscle contraction force when neuromuscular electrical stimulation (NMES) of 50% MVIC was applied. Sixteen subjects (8 male, 8 female) without neuromuscular disease volunteered to participate in the study. All subjects were divided into two subgroups: control (no electrical stimulation) group and 50% maximal voluntary isometric contraction (MVIC) group. NMES training program was performed in the calf muscle three times a week for 10 weeks. Before and after the experiments, the MVIC of ankle plantar flexor was measured by the use of dynamometer, and the ultrasonography in the gastrocnemius medialis muscle was measured. The following results were obtained; MVIC was significantly increased in the electrical stimulation groups. Pennation angle, muscle density, and white area index also considerably changed in the electrical stimulation groups. In conclusion, the NMES training of 50% MVIC, comparative low level, improved the skeletal muscle architecture and the qualitative properties as well as the muscle contraction force.

• Journal of Environmental Impact Assessment
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• v.22 no.5
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• pp.439-454
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• 2013

UN-REDD (United Nations programme on Reducing Emissions from Deforestation and forest Degradation) is currently being emerged as one of important mechanism to reduce carbon dioxide in relation to the deforestation. Although administrative boundary has already gained world-wide recognition as a typical method of monitoring unit in the process of GHG (Greenhouse Gas) reduction project, this approach did not provide a realistic evidence in the carbon sequestering monitoring in terms of UN-REDD; the meaningful comparison of land use patterns among watershed boundaries, interpretation for distribution trends of carbon density, calculation of opportunity cost, leakage management, etc. This research proposes a comparative evaluation framework in a more objective and quantitative way for carbon sequestering monitoring between administrative and watershed boundary approaches. Mt. Geumgang of North Korea was selected as a survey objective and an exhaustive and realistic comparison of carbon sequestration between the two approaches was conducted, based on change detection using TM satellite images. It was possible for drainage boundary approach to identify more detailed area-wide patterns of carbon distribution than traditional administrative one, such as estimations of state and trends, including historical trends, of land use / land cover and carbon density in the Mt. Geumgang. The distinctive changing trends in terms of carbon sequestration were specifically identified over the watershed boundary from 4.0% to 34.8% while less than 1% difference was observed in the administrative boundaries, which were resulting in almost 21-22%. It is anticipated that this research output could be used as a valuable reference to support more scientific and objective decision-making in introducing watershed boundary as carbon sequestering monitoring unit.

• Imaging Science in Dentistry
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• v.31 no.3
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• pp.129-133
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• 2001

Purpose: To compare the copper equivalent values measured at premolar and molar areas in the copper equivalent images of panoramic and intraoral radiographs and to evaluate the possibility of the copper equivalent images of panorama for the assessment the bone density. Materials and Methods : Intraoral radiograms at mandibular premolar and molar area and panoramas of 6 human dry skulls were taken with copper-step wedge by Heliodent MD (Siemens Co., Germany) and by Planmeca (PM 2002 CC, Planmeca, Helsinki, Finland) were used for experiment. The copper equivalent values measured at premolar and molar areas in the copper equivalent im ages of panorama and intraoral film were compared. Results: The copper equivalent values were ranged 0.20 mmCu-0.44 mmCu at the molar areas, 0.05 mmCu-0.31 mmCu at the premolar areas on panoramic images. There were no significant differences (p>0.5) between the copper equivalent values on intraoral images and those on panoramic images measured at premolar areas and molar areas respectively. The correlation coefficient between the copper equivalent values on intraoral images and those on panoramic images was respectively 0.8495 at molar areas and 0.6184 at premolar areas. Conclusions : The copper equivalent images of panorama for the assessment the bone density appeared to be significant at molar area compared with the one of intraoral radiograph.