• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.270-276
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• 1997

The purpose of this study was to investigate the number of climbing plant species habitated in South Korea. Relationships between their distribution and environmental factors were surveyed. Research sites for vertical distribution were Mt.S rak, Mt.Kwangkyo, Mt. Eoudap and Mt. Chiri. The results of this study are as follows: The number of climbing plants habitated in South Korea was 267 species, 95 genera, 41 families. According as latitude lower, the number of climbing plant species increased. And most areas of Korean peninsula except for alpine regions and the northern part of North Korea seemed to be suited for the growth of climbing plants. The number of climbing plant species decreased with its altitude. And it is confirmed that their distributions were limited to the below of 1,500m sea level which was applicable to the area of Kira's warmth index above 45. The species of climbing plants changed with its plant community although at same altitude. The number of climbing plant species was different from the face of slope, and the species diversity became lower at south slope than that of north slope.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.56-71
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• 2003

Waste landfills have been the center of environmental problems and they must be restored due to environmental pollution, disgusting landscape, and cost of management. It is suggested that they be recycled urban space as cities expand. Specially, nonsanitary waste landfills which have no pollution prevention facilities cause serious problems. Restoring the landfills as parks and golf courses, so on makes more benefits because of cheap use land, closeness to urban area, flat topography applicable to parks and golf courses, and high land values after restoration and the changes to local recreation sites. Restoration of waste landfills is a complex, costly, and interdisciplinary work. But, the waste landfill is a manmade ecosystem. Control, restoration and postmanagement of waste landfills are very important problems. The role of vegetation prevents soil erosion, reduces soil water storage, and obstructs leachate seepage. Early restoration makes derelict lands into man park artificially geared to soil, vegetation, landforms and hydrology. But, Ideal restoration is to make stable ecosystem nature-friendly and compatible with surrounding landscape without more management. Landscape is structured hierarchically with patches and stands as small components and forms forest as large components. Therefore, landscape formation of the waste landfills needs much restoration process. There are many ecological restoration techniques for the waste landfills. Those are divided into artificial and natural methods. The artificial method is anthropogenic plantings while the natural method is to trigger and use succession processes. The most important thing in the restoration of waste landfills is to consider the final restoration objectives of each waste landfill. According to these objectives, the depth of covering layer, planting degree, and structural design should be determined. The effective restoration methods should be selected of artificial and natural options.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.4
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• pp.336-350
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• 2001

The purpose of this study was to investigate corrosion tendency and to compare corrosion resistance of three dental magnetic attachments and its keeper alloy by coercive, electrochemical method. By using petentiodynamic polarization technique, magnetic elements and its keeper alloy of Magfit EX600 system(MF, MFK), Dyna ES regular system(DN, DNK) and Shiner SR magnet system(SR, SRK) were corroded electrochemically in 0.9% NaCl electrolytic solution. Open-circuit potential and anodic polarization curve was measured with Potentiostat(model 273 EG&E) and polarization curve was created by current density per square area following scanning of increased series of voltage in the rate of 1.0mV per second. Before and after electrochemical corrosion, the surface roughness test was done. Thereafter the change of mean surface roughness value(Ra) and mean peak value(Rt) of surface roughness was compared one another. In order to observe the corroded surface of each specimen, metallurgical light microscopic(${\times}37.5$) and scanning electron microscopic view(SEM ${\times}100$) was taken and compared one another. Conclusion is followings. 1. All of six covering metal of dental magnetic attachments and its keeper alloy were corroded in various degree after electrochemical corrosion. 2. The corrosion resistance of which used in this experiment is the following in high order; DNK, MFK, DN, MF, SRK and SR. 3. Especially Shiner magnet system and its keeper alloy were more severely corroded after electrochemical corrosion and the change of Ra Rt value were more increased than others. 4 Metallurgical and scanning electron microscopic view showed the pitting corrosion tendency of all experimental alloy but DNK and SR. 5. Covering metal of magnet was more corroded than its keeper alloy.

• Steel and Composite Structures
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• v.22 no.1
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• pp.63-77
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• 2016

Top-down construction is a construction technique in which pit excavation and structure construction are conducted simultaneously. Reducing construction time and minimizing noise and vibration which affect neighboring structures, the technique is widely employed in constructing downtown structures. While H-steel columns have been commonly used as core columns, concrete filled steel tube (CFT) columns are at the center of attention because the latter have less axial directionality and greater cross-sectional efficiency than the former. When compared with circular CFT columns, square CFT columns are more easily connected to the floor structure and the area of percussion rotary drilling (PRD) is smaller. For this reason, square CFT columns are used as core columns of concrete encased and filled square (CET) columns in underground floors. However, studies on the structural behavior and concrete stress transfer of CET columns have not been conducted. Since concrete is cast according to construction sequence, checking the stress of concrete inside the core columns and the stress of covering concrete is essential. This paper presents the results of structural tests and analyses conducted to evaluate the usability and safety of CET columns in top-down construction where CFT columns are used as core columns. Parameters in the tests are loading condition, concrete strength and covering depth. The compressive load capacity and failure behavior of specimens are evaluated. In addition, 2 cases of field application of CET columns in underground floors are analyzed.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.1
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• pp.29-35
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• 2006

A guideline for decision of dispersants use zone was developed at the twelve local sea areas covering the whole Korean sea. In this study, the water depths and damage to sensitive resources were considered as the conditions of the decision of whether or not to use dispersants. According to the conditions of the decision, three kinds of zones were specified as following; 1) dispersants usable zone, 2) dispersants use approvable zone, 3) dispersants use restrictive zone. As the result, dispersants use zone at the twelve local sea areas covering the whole Korean sea are suggested.

• Journal of Chest Surgery
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• v.36 no.5
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• pp.363-366
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• 2003

Background: Left ventricular rupture after acute myocardial infarction is a serious complication with high mortality. Emergency operation is usually the only available treatment. A 76-year-old female with persistent chest pain and syncopal attacks was admitted. Transthoracic echocardiography showed the pericardial effusion and generalized hypokinesia of the inferolateral wall of left ventricle. Coronary angiography revealed a total occlusion of the first diagonal branch. After percutaneous transluminal coronary angioplasty with coronary stent and insertion of intraaortic balloon pump, emergency operation was performed. Under cardiopulmonary bypass and cardiac arrest with cold blood cardioplegia, coronary artery bypass graft with saphenous vein, pericardial patch covering on the rupture area with 6-0 polypropylene running sutures, and fibrin glue compression under the patch were performed. We present a case of left ventricular (free wall) rupture after acute myocardial infarction.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.10
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• pp.483-488
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• 2016

In this paper, we propose a prototype-based classification learning by using the nearest-neighbor rule. The nearest-neighbor is applied to segment the class area of all the training data with hyperspheres, and a hypersphere must cover the data from the same class. The radius of a hypersphere is computed by the mid point of the two distances to the farthest same class point and the nearest other class point. And we transform the prototype selection problem into a set covering problem in order to determine the smallest set of prototypes that cover all the training data. The proposed prototype selection method is designed by a greedy algorithm and applicable to process a large-scale training set in parallel. The prediction rule is the nearest-neighbor rule and the new training data is the set of prototypes. In experiments, the generalization performance of the proposed method is superior to existing methods.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.192-196
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• 2005

Key part of main equipment in a gas turbine may be likely to be damaged due to operation under high temperature, high pressure, high-speed rotation, etc. Accordingly, the cost for maintenance increases and the damaged parts may cause generation to stop. The number of parts for maintenance also increases, but diagnostics technology fur the maintenance actually does not catch up with the demand. Blades are made of precipitation hardening Ni superalloy IN738 and the like for keeping hot strength. The surface of a blade is thermal-sprayed, using powder with main compositions such as Ni, Cr, Al, etc. in order to inhibit hot oxidation. Conventional regular maintenance of the coating layer of a blade is made by FPI (Fluorescent Penetrant Inspection) and MTP (Magnetic Particle Testing). Such methods, however, are complicated and take long time and also require much cost. In this study, defect diagnostics were tested for the coating layer of an industrial gas turbine blade, using an infraredthermography camera. Since the infrared thermography method can check a temperature distribution on a wide range of area by means of non-contact, it can advantageously save expenses and time as compared to conventional test methods. For the infrared thermography method, however, thermo-load must be applied onto a tested specimen and it is difficult to quantify the measured data. To solve the problems, this essay includes description about producing a specimen of a gas turbine blade (bucket), applying thermo-load onto the produced specimen, photographing thermography images by an infrared thermography camera, analyzing the thermography images, and pre-testing for analyzing defects on the coating layer of the gas turbine blade.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.4
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• pp.83-94
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• 2007

Test application of revegetation measure was made on the roadside slope damaged by Gimcheon-Eomo national road improvement project in a bid to prevent the soil from being washed out as well as to restore the ecological environment, and the survey for assessing the effect of slope revegetation measures was conducted, beginning Sep 7 through Sep 20, 2006. In the wake of comprehensive reviewing and evaluating the surrounding topographic environment, physical and chemical characteristics of soil, germination of revegetation plants, analysis of bio mass, covering ratio and the plants appeared, revegetation measure C was found to have been most effective and desirable for further application in the area. Viewing the specific applicability by the area, revegetation measure C and C-1 appeared to be appropriate for blasting rock slope and ripping rock slope as they are efficient in preventing the slope from being washed out and in early revegetating. And revegetation measure B deemed to be effective to blasting rock slope or ripping rock slope as an alternative. And for cut slope, vegetation measure C-2 was judged to be more effective than measure D or E, while measure C-3 would be appropriateto embankment slope.

• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1825-1838
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• 2016

The detection of skin pigment is crucial in the diagnosis of skin diseases and in the evaluation of medical cosmetics and hairdressing. Accuracy in the detection is a basis for the prompt cure of skin diseases. This study presents a method to recognize and measure human skin pigment using Hemoglobin-Melanin (HM) coordinate. The proposed method extracts the skin area through a Gaussian skin-color model estimated from statistical analysis and decomposes the skin area into two pigments of hemoglobin and melanin using an Independent Component Analysis (ICA) algorithm. Then, we divide the two-dimensional (2D) HM coordinate into rectangular bins and compute the location histograms of hemoglobin and melanin for all the bins. We label the skin pigment of hemoglobin, melanin, and normal skin on all bins according to the Bayesian classifier. These bin-based HM projective histograms can quantify the skin pigment and compute the standard deviation on the total quantification of skin pigments surrounding normal skin. We tested our scheme using images taken under different illumination conditions. Several cosmetic coverings were used to test the performance of the proposed method. The experimental results show that the proposed method can detect skin pigments with more accuracy and evaluate cosmetic covering effects more effectively than conventional methods.