• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.251-256
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• 2003

The capability of pilot injection with small fuel quantity at all engine operating conditions is one of the main feature of the common rail system. The purpose of the pilot injection is to lower the engine noise and to reduce the NOx emissions. This study describes the pilot spray structure characteristics of the common-rail diesel injectors, solenoid-driven and piezo-driven type, with different electric driving characteristics So, three common-rail injectors with different electric current wave were used in this study. The pilot spray characteristics such as spray speed, spray tip penetration, and spray angle were obtained by spray images, which is measured by the back diffusion light illumination method with optical system for high-speed temporal photography. Also the CFD analysis was carried out for fuel behavior under high pressure in between needle and nozzle of solenoid-driven injector to know the condition of initial injection at experiment test. It was found that pilot injection of common-rail system was effected by rate of injection and temperature of injected fuel and electrical characteristic of the driven injector.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.387-392
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• 2009

As Our society's environmental awareness and concern the significant increases, the importance of the legal system for environmental conservation such as the Prior Environmental Review System, Environmental Impact Assessment is growing increasingly. but, still critical issues are present such as reliability. Though there could be various causes such as the system or procedures etc. Above all, basically the environmental data problem is the critical cause. Therefore, this study was trying to improve the environmental data accuracy using the high-resolution color aerial photography, LiDAR data and Object Oriented Classification method. And in this study, classification based on coverage percentage of a particular species was attempted through the multi-resolution segmentation and multi-level classification method. The classification result was verified by comparison with 11 points local survey data. All 11 points were classified correctly. And even though the exact coverage percentage of the particular species did not be measured, It was confirmed that the species was occupied similar portion. It is important that the environmental data which can be used for the conservation value assessment could be acquired.

• Journal of Fashion Business
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• v.8 no.5
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• pp.75-84
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• 2004

Fashion Illustration has become a key method in expressing Fashion, and is being applied in various fields of the modern world, where changes are so rapid that prescribing trends are meaningless. Fashion Illustration was stimulated through progress of wood block printing and development of printing techniques, and grew with fashion magazines. Fashion Illustration advanced along with the appearance of newspapers and magazines that were emerged due to historical demands such as development of printing techniques, spacial spread of human life, obliteration of traditional societies, diffusion of education systems, progress in postal systems, and appearance of commercial broadcast. Fashion Illustration showed growth and decline along with the influence of mass media such as magazines and photography, and the general publics demand. In this study, the author reviews Le Nouvau Mercure Galant, the magazine that first dealt with Fashion Illustrations. The author analyses the magazine in six stages of formation, growth, revolution, golden-age, decline, and reconstruction, to develope a theoretical analysis of Fashion Illustration and to give direction of use of Fashion Illustration in the future.

• Journal of Fashion Business
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• v.15 no.2
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• pp.23-38
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• 2011

This research is to examine the formative of patterns and characteristics of expression in Danzhai Miao batik of Guizhou China and to reveal the cultural factors and characteristics of artistic expression inherent to it. As the research methodology, theoretical study was done by utilizing the preceding research data, literature data at home and abroad, photo data, and Internet data, and as the empirical research, field trip was made to Guizhou China and investigation and experiment of dyeing techniques, purchase of dyeing craftworks, photography shooting, and interviews were conducted. The results of this research showed that ancient Chinese batik began in Miao in the Jinhan era and the three types of Miao's traditional batik, i.e. Danzhai batik, Huangping batik, Anshun batik. Danzhai Miao batik obtained indigo blue white patterns through traditional production techniques and natural dyeing batik and represented Miao batik of Guizhou. In the expression of Danzhai Miao batik, based on the cultural backgrounds, the formative such as symbolic of patterns, tradition, primitive, reality, abstract, and decorative of dress designs and high dignity of artistry of creative batik patterns be found from the aspect of expressing magnanimous nationality.

• Journal of radiological science and technology
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• v.23 no.1
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• pp.55-61
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• 2000

This report was the results of an investigation based on the status of the mammography in the 45 medical facilities in the areas of Seoul and Kyong-Gi Do. In regard to mammography we were able to understand the rectification method of the generator, the functions, the radiographic techniques, the patient exposure dose, etc. Recently, the occurrence of breast cancer has rapidly increased and has lead to increased interest in the early discovery of breast cancer. However, mammography has not kept up with the publics interests and its demand. The main problem is thought to be a wide great difference in the quality of the facilities, especially in the techniques of radiograpic and the capabilities of the generator, which would have a major effect on the grade management of the image quality. In order to be ready and keep up with the high rate of increase of breast cancer, the standardization of mammography and the grade management is urgently required as a solution to the problems in the increase of image qualify and the decrease of dose. It is regarded that the basic guide of the techniques of photography in the mammography, which is being used in all developed countries due to the influence of the USA, should be presented, especially in Korea, and for this, more active and enthusiastic education and enlightenment should be needed.

• Economic and Environmental Geology
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• v.29 no.4
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• pp.429-437
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• 1996

The purpose of this study is to correct the nodule abundance of FFG (Free Fall Grab) sampler on KODOS (Korea Deep Ocean Study) area in North-East Pacific Ocean. The image analysis of sea-floor photography was carried out for correcting the abundance of nodules, and the image enhancement techniques and edge detection method were used to discriminate between nodules and sediments. The trace of nodules on sediments was detected to reduce the fractionation effect in calculating the coverage of nodules. The three methods, using the coverage of nodules, using the volume density, and using corrected volume density, were utilized for the correction of the nodule abundance. The method using the coverage of nodules was more convenient and available for the correction of nodule abundance than the other two methods. The method using the corrected volume density had the highest confidence level compared with the other methods.

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.220-227
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• 1997

The purpose of our study is to evaluate the ability of nickel-titanium(NiTi) files in maintaining the original curvature of a curved root canal during canal preparation. Curved canals on translucent resin blocks were prepared with NiTi and stainless steel files, and they were placed at the platform which can reproduce the same position. The unprepared and prepared canal forms were accurately compared by double exposure technique of photography. By finite element methods we also analyzed stress distributions of NiTi and stainless steel files in a curved canal. The results were as follows : 1. NiTi files were excellent in maintaining the original curvature of a curved canal than stainless steel files after canal preparation. 2. The results of canal preparation with these files were well verified by the analysis of stress distributions using finite element methods.

• International Journal of Aeronautical and Space Sciences
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• v.4 no.1
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• pp.26-33
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• 2003

Recess is a geometrical configuration shape that the exit surface of an inner injector is located at a certain length inward from that of an outer injector. It is known to have the characteristics that it can augment mixing efficiency and flame stabilization through internal mixing of propellant in it. So, various experiments, such as backlit stroboscopic photography, phase Doppler particle analyzer(PDPA) and mechanical patternator, were performed at several recess lengths to grasp its effect on the spray characteristics of spray angle, breakup length, atomization and' mixing. Recess length was normalized to dimensionless recess number and two principal mechanisms of impingement and swirl recovery were introduced to explain its influence on the spray characteristics. The effect of recess on SMD doesn't appear significantly near the recess number where mixing efficiency attains to the maximum, whereas mass distribution and mixing efficiency are changed considerably. Thus, it can be inferred that a certain optimum recess number exists, where mixing efficiency becomes the maximum.

• Journal of Internet Computing and Services
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• v.21 no.5
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• pp.31-37
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• 2020

Last year's Goseong-Sokcho forest fires have highlighted the limitations of extinguishing work for night-time forest fire and the importance of quick identification for information on the spread of forest fire. However, it is not easy to find services that take into account the characteristics of forest fires, as most existing disaster-related mobile applications and research assume various disaster situations rather than just forest fire situations. Therefore, a system that can provide information quickly is needed, taking into account the characteristics of forest fires and the limitations of extinguishing work. In this paper, we propose evacuation route guidance services that bypass areas where fire has already spread, supplement existing methods of extinguishing work, and provide general information on forest fire situations in real time, by putting drones into forest fire situations. It has been implemented to automate image analysis using the Rekognition service of Amazon Web Service (AWS), and the results of fire detection and the T Map API guide the evacuation path. It is expected that the results of this paper will allow efficient and rapid rescue and extinguishing work to be carried out, and further reduce the damage of human life caused by forest fires.

• Journal of Fashion Business
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• v.4 no.2
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• pp.95-111
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• 2000

The purpose of this research is to investigate the concept of the photomontage technique, one of the various photographic techniques, and to analyze the photomontage image through the patterns that appeared in 1990's fashions. Moreover, by making clothes using the photomontage image, the intention of this study to apply the technique in real life is achieved. The results of this thesis for making clothes utilizing image of the photomontage are as followings. First, the photomontage expands the variety of materials that can be used, because the clothes using the photomontage image are able to take any photo images. Second, two different eras can co-exist in a piece of work since a photomontage work can uses two images from different eras. Third, it allows greater adaptability by expressing variety and utility in the making of the casual styles using conventional photo materials. The conclusion of this study is that the clothes appearing in the late 20th century using the photomontage image have been developed corresponding to the accelerated development of photography, machinery, and technical skill in civilization. Trends break away from the conventional expressions of art. This is a new trend and direction in art that will effect culture in the 21st century. The photo montage image would show the possibility of a good unification between human being and machines.