Byung-Jin Choi - Academia.edu (original) (raw)
Papers by Byung-Jin Choi
Applied Microscopy, 2018
Immunoelectron microscopy using an antigen-antibody reaction in an electron microscope is a very ... more Immunoelectron microscopy using an antigen-antibody reaction in an electron microscope is a very useful tool to identify the components of a tissue in an electron microscope. Many researchers also use immunoelectron microscopy. Nonetheless, immunoelectron microscopy is rarely introduced systematically, and immunoelectron microscopy can be carried out without fully understanding the principles, and cases of poor understanding can often be seen in the vicinity. Therefore, in order to make it easier to understand, we will first introduce the principles of immunoelectron microscopy and describe practical methods.
Morphological Comparison of Spermatozoa in the Korean Greater Horseshoe Bat (Rhinolophus ferrumequinum korai) and Long-Fingered Bat (Miniopterus schreibersi fuliginosus)
Applied Microscopy, 1999
The aim of the present study was to investigate with transmission electron misroscope the compara... more The aim of the present study was to investigate with transmission electron misroscope the comparative morphology of epididymal spermatozoa in two species of the Korean insectivorous bats belonging to 'prolonged sperm storage' type (Rhinolophus ferrumequinum korai) and 'delayed implantation' type (Miniopterus schreibersi fuliginosus). Sperm head of the R. ferrumequinum korai was bullet shaped and that of M. schreibersi fuliginosus was spatula shaped. The nuclei of the sperm head of the R. ferrumequinum korai and M. schreibersi fuliginosus occupied two-third and a half of it, respectively. The segmented columns of R. ferrumequinum korai were about 12 to 14 in number, and those of the M. schreibersi fuligincsus were about 10 to 12. Particularly, a pile of the satellite fibers in middle piece of R. ferrumequinum korai remained the inner aspect of the outer dense fibers, but those of the M. schreibersi fuliginosus were not.
국내 플라워샵 판매현황에 관한 연구 －품목별 판매율이 높은 화훼상품과 성수기를 중심으로－
Journal of People, Plants, and Environment, 2020
Background and objective: This study was conducted to investigate the effect of an agro-healing p... more Background and objective: This study was conducted to investigate the effect of an agro-healing program on the relationship satisfaction and emotional change between parents and children. Methods: We sent an official letter to D Office of Education with information and recruitment for the agro-healing program. Then D Office of Education has sent the official letter to elementary schools under the jurisdiction to recruit parents who were willing to participate in the programs with their children. The subjects were recruited by order of application, and 27 families participated, but 20 parent-child teams who attended all sessions and fully participated in the program were ultimately selected. From October 12 to November 16, 2019, a total of 6 sessions of the programs were held once a week at a care farm in Gyeongsangbuk-do. In the morning, they participated in a program that utilizes the resources of plants and animals in the care farm, and later participated in an indoor horticultural program in the afternoon. Results: In the parent-child relationship satisfaction test, it was found that communication was significantly increased after participating in the agro-healing program (p = .047). There were no statistically significant changes in the sentence completion tests written by the children, but their potential perception or attitude towards their parents changed more positively than before according to the content of the sentences. Conclusion: The agro-healing program could strengthen the relationship between parent and child by improving the parent-child relationship satisfaction and children's emotional attitude towards their parent.
Korean Journal of Nature Conservation, 2016
We investigated the mammals in Mt. Yeonin, Gyeonggi-do. A total of 20 species belongings 11 Famil... more We investigated the mammals in Mt. Yeonin, Gyeonggi-do. A total of 20 species belongings 11 Familes, 6 Oders, were identified in the survey area. The confirmed mammal is Erinaceus amurensis,
Korean Journal of Nature Conservation, 2011
This study was conducted to identify the distribution characteristics of small village wetlands i... more This study was conducted to identify the distribution characteristics of small village wetlands in Geumsan County, an inland mountain zone, and comparing with Seocheon County, a coastal plain area with different ecological environment characteristics. Using Arc-GIS (v10.1) the village wetland code was extracted to derive the possible location of the village wetland, and the final distribution of the village was obtained by performing indoor judging work based on satellite images, aerial photographs, topographical maps, Korea Land Information System (KLIS), land use level, land cover degree (division), and land use status by local surveying and indoor analyzing. Although Geumsan County (576.66km2) is more than 60% larger than Seocheon County (358.04km2), 607 villages in Geumsan County and 570 villages in Seocheon County are capable of making similar levels of 106.5% of wetlands, but only a fraction of those in Seocheon County were found to be 67.6%. The density of the village wetlands was much lower than that of Seocheon County, a coastal plain area, because there were many mountainous areas in Geumsan County, and most of the wetlands temporarily created for water supply were removed during the analysis phase of the Jeongsa Image, so the actual wetlands of the village were judged to be only two-thirds different from those of Seocheon County.
Reduction Effect Analyses of Particulate Matter Emissions from Buildings by Fuel Cell Systems Combined with Absorption Chiller-Heaters
Journal of The Korean Society of Living Environmental System, 2018
Computational Intelligence and Neuroscience, 2020
We propose three quality control (QC) techniques using machine learning that depend on the type o... more We propose three quality control (QC) techniques using machine learning that depend on the type of input data used for training. These include QC based on time series of a single weather element, QC based on time series in conjunction with other weather elements, and QC using spatiotemporal characteristics. We performed machine learning-based QC on each weather element of atmospheric data, such as temperature, acquired from seven types of IoT sensors and applied machine learning algorithms, such as support vector regression, on data with errors to make meaningful estimates from them. By using the root mean squared error (RMSE), we evaluated the performance of the proposed techniques. As a result, the QC done in conjunction with other weather elements had 0.14% lower RMSE on average than QC conducted with only a single weather element. In the case of QC with spatiotemporal characteristic considerations, the QC done via training with AWS data showed performance with 17% lower RMSE tha...
Journal of Korea Society for Plants People and Environment, 2017
The purpose of this study is to look into the effect of a horticultural activity program on caree... more The purpose of this study is to look into the effect of a horticultural activity program on career women's job satisfaction. As the research subject, this study set 37 career women of 6 occupational clusters, such as elementary school teachers, nurses, social workers, care teachers, and police officers in 'P' city, and financiers in 'D'city. The horticultural activity program was applied for about 10 months from June 2013 to April 2014, and for each job group the program was executed once a week and a total of 8 sessions. As a result of the analysis of job satisfaction by conducting horticultural activity by 6 occupational cluster, occupational clusters like an elementary school teacher, and social worker showed a significant improvement in job satisfaction immediately after horticultural activity was conducted, and in 4 weeks after that, all 5 occupational clusters but a care teacher cluster were found not to show a significant difference. It is expected that various horticultural activity programs would provide emotional stability to working women and consequently improve their overall quality of life. As a result of the above research, this study confirmed that improvement in job satisfaction is more effective when a person steadily participates in gardening activity rather than doing gardening activity temporarily. In addition, this study confirmed that gardening activity could be an alternative remedy which provides a positive change to a career woman's job satisfaction.
Study on the contribution ratios of particulate matter emissions in differential provinces concerning condensable particulate matter
Energy & Environment, 2019
This study attempted to reanalyze the emission property of particulate matter and set up the stra... more This study attempted to reanalyze the emission property of particulate matter and set up the strategy on the emission reduction of particulate matter by considering the condensable particulate matter additionally as the total particulate matter together with filterable particulate matter. For this, total suspended particles and particulate matter 2.5 emitted in 2013 were selected as pollutants. Fuel classifications were divided into major and minor categories, and the sources were divided into major, medium, and minor categories. Three provinces were set as administrative areas: Gyeonggi-do, Chungcheongnam-do, and Jeollanam-do. The condensable particulate matter emission factors used were obtained from National Institute of Environmental Research. The condensable particulate matter emission factors of liquefied natural gas, diesel, and bunker C oil were measured in boilers with no preventive facilities, and the coal power plant emission factor was obtained at the end of the prevention facility. The condensable particulate matter emissions were calculated by multiplying the particulate matter 2.5 filterable particulate matter emissions by the ratio of the condensable particulate matter emissions to the filterable particulate matter of the National Institute of Environmental Research data. Different patterns of emission sources were observed for each province depending on the consideration of condensable particulate matters. Considering only the filterable particulate matters, the proportion of mobile pollutants was high. On the other hand, considering the condensable particulate matters, the contribution of the nonindustrial combustion category emissions using gaseous fuels, such as city gas, increased in the metropolitan area, whereas the contributions of the manufacturing combustion category emissions increased in the nonmetropolitan areas. Therefore, in the case of collecting energy facilities and the manufacturing burning facilities planned in the local cities in Korea, it is necessary to consider the filterable particulate matter, and condensable particulate matter emission amount.
Journal of People Plants and Environment, 2017
As a result of inquiring into the analysis consequent on a symptom by research subject, it was fo... more As a result of inquiring into the analysis consequent on a symptom by research subject, it was found that there were 1 paper (1.5%) which did research for the purpose of rehabilitation of the general public, 26 papers (38.8%) targeting diagnosis-related groups (DRG), and 40 papers (59.7%) targeting social consideration subject. Also, as a result of the inquiry about the frequency & number of times of horticultural therapy program implementation, it was found that 49 papers (73.1%) implemented one time a week, and 45 papers (67.2%) were surveyed as the highest by conducting a total of 11~20 sessions of horticultural therapy programs, In the analysis of horticultural therapy activities by type, plant cultivation activity was found to be the most 506 times, accounting for 41.5%, followed by 297 time crafts activity (24.4%), 213 time floral decoration activity (17.5%), and 203time others activities (16.7%). In cultivation activity, soil-using cultivation activity (25.1%) was found to be lower than the proportion (74.9%) of soiless cultivation (16.4%), crafts activity (24.4%), floral decoration activity (17.5%) and other activities (16.7%). The most used plants in a restricted place like a hospital were found to be in the order of Hedera helix, Chamaedorea elegans, Succulent plant, Syngonium podophyllum, Neofinetia falcata HU, Hoya carnosa (L.f.) R.Br.), Rosmarinus officinalis, and Spathiphyllum spp.
Tuberculosis and Respiratory Diseases, 2009
Pulmonary papillomas are rare benign epithelial neoplasms arising in bronchial surface epithelium... more Pulmonary papillomas are rare benign epithelial neoplasms arising in bronchial surface epithelium. They are categorized by a variety of cell types including squamous, glandular, and mixed squamous and glandular type. Among them, glandular papilloma is extremely rare and has not been reported in Korea. The patient was a 52 year-old man presenting with a 4-months' history of recurrent hemoptysis. Bronchofiberoscopy revealed a whitish, glistening, and polypoid mass lesion at the proximal bronchus in the basal segment of the left lower lung. Bronchoscopic biopsy was performed; papillary fronds lined by ciliated or nonciliated pseudostratified columnar epithelium were noted on histologic findings. We present the first case of glandular papilloma in Korea. Two years later, the patient visited our hospital again due to hemoptysis. On follow-up bronchoscopy, a mass that had been found previously showed an increase in size.
P-23: Design Parameters for Using Charging Technique for TFT-LCDs
SID Symposium Digest of Technical Papers, 2007
In case of charging a large capacitor in a short time, We use a well-known pre charging technique... more In case of charging a large capacitor in a short time, We use a well-known pre charging technique(1), which is a method of charging a pixel two times at an interval of one gate pulse width. But there is a side effect of a pattern looking like out of focus. This phenomenon is caused directly by a different quantity of charging being introduced into two pixels which are two pixels apart vertically with each other. To remove this side efeect, we optimize the charging design parameter; Cst+Clc, Ion condition from TFT device. with the pre charging technique, A 120Hz 32″ WXGA TFT-LCD which has three times of Cst + Clc as compared to conventional IPS structure has been developed.
During the last 10 years, there have been many efforts in some areas of Natural Language Processi... more During the last 10 years, there have been many efforts in some areas of Natural Language Processing to encode the normal text or documents into machine readable form. If we encode written data using a canonical form which can be recognized by a computer, we can extract needed information and process and utilize it for another purposes. From this point of view, we present an account of the encoding of a printed dictionary. The construction of a lexicon is very time-consuming and expensive work and the application of the lexicon is restricted. In this paper, we describe a logical structure for Korean printed dictionaries as a general lexical representation based on SDML, which can be transformed into another representation for different application requirements.
Fabrication and Properties of Flexible OLEDs on Polyimide-Graphene Composite Film Substrate
Molecular Crystals and Liquid Crystals, 2013
ABSTRACT
Journal of the European Ceramic Society, 1992
C3H 8 was added in order to obtain stoichiometric ~3-SiC in the MTS + H 2 CVD system. The experim... more C3H 8 was added in order to obtain stoichiometric ~3-SiC in the MTS + H 2 CVD system. The experiments were carried out by using a cold-wall reactor under atmospheric pressure in the temperature range 1100-1500C. XRD, Vickers microhardness tester and SEM were used in characterizing the stoichiometry and morphology, hi the absence of C3H s the tenlperature required jor the deposition ()[" stoichiometric SiC was above 1500 ° C, otherwise excess Si was codeposited with SiC. With C3H8 addition, however. stoichiometric SiC could be obtained even at temperatures as low as 1200C and the pr¢lerred orientation was changedJi'om (220) to (111). The mierostructure and har~hless value were related to the pre/'erred orientation and stoichiometrv of the coathTg layers, re,v~ectively.
Journal of the American Ceramic Society, 2005
The effects of microstructure and residual stress on the mechanical properties of Si 3 N 4-based ... more The effects of microstructure and residual stress on the mechanical properties of Si 3 N 4-based three-layer composite materials were investigated. The microstructure of each layer was controlled by the addition of two differently sized silicon carbides: fine SiC nanoparticles (∼200 nm) or relatively large SiC platelets (∼20 µm). When the SiC nanoparticles were added, the average grain size of Si 3 N 4 was reduced because of the inhibition of grain growth by the particles. On the other hand, when the SiC platelets were added, the microstructure of Si 3 N 4 was not much changed because of the large size of the platelets. Three-layer composites were fabricated by placing the Si 3 N 4 /SiCnanoparticle layers on the surface of the Si 3 N 4 /SiC-platelet layer. The residual stress was controlled by varying the amount of SiC added. The mechanical properties of threelayer composites with various combinations of microstructure and residual stress level were investigated.
Journal of the American Ceramic Society, 2005
Si 3 N 4 ceramics reinforced with SiC platelets were fabricated by hot pressing at 1800°C. The mi... more Si 3 N 4 ceramics reinforced with SiC platelets were fabricated by hot pressing at 1800°C. The microstructure of the Si 3 N 4 matrix itself was the same with or without the addition of the SiC platelets. However, the mechanical properties of the Si 3 N 4 were changed remarkably by the SiC addition. The fracture toughness and the crack resistance with crack propagation (R-curve behavior) were improved while the fracture strength was decreased slightly by the platelets. Improvement in crack resistance was attributed to the extensive interaction of cracks with the platelets. The reduction in strength, on the other hand, is believed to be due to cracks associated with weak platelet-matrix interfaces.
Growth of silicon carbide by chemical vapour deposition
Journal of Materials Science Letters, 1991
Silicon carbide (SIC) has some oustanding properties such as high hardness, chemical inertness an... more Silicon carbide (SIC) has some oustanding properties such as high hardness, chemical inertness and thermal stability. These properties have attracted great interest in its structural and device use, especially at high temperature. Since Pring and Fielding [1] synthesized SiC by chemical vapour deposition (CVD) using C6H 6 and SiC14 as a precursor, many efforts [2-5] have been made to investigate the precursors of Si and C. Recently methyltrichlorosilane (MTS; CH3SiC13)has been the most frequently used precursor [6-8], because MTS contains the same number of Si and C atoms and thus can easily produce stoichiometric SiC. From thermodynamic calculations on the CVD of SiC in the MTS + H2 system, Kingon et al. [9] developed CVD phase diagrams and reported that only SiC single phase can be deposited in a wide range of temperature and MTS molar fraction. However, in experimental works by others it has been reported that excess Si [10] or excess C [11] is codeposited with SiC under some conditions, and relatively strict control in the deposition conditions is required for the stoichiometric growth of SiC. In this work we examined the stoichiometric growth of SiC in the MTS + H2 system, and obtained SiC films without Si or excess C phases at a temperature of 1500 °C, but excess Si phase was always observed at <1500 °C. For the deposition experiment we used a conventional horizontal cold-walled reactor which consisted of a quartz tube (inside diameter 26 mm) and a SiC-coated graphite susceptor heated by r.f. induction. The MTS vapour was carried by H2 from an MTS container which was maintained at 0 °C. The molar fraction of MTS was controlled by adjusting the flow rate of carrier gas. The temperature of the substrate, located on a tilted susceptor, was measured with an optical pyrometer calibrated with SiC emissivity [12]. The detailed experimental conditions are listed in Table I. The film thickness was measured by gravimetry and identified by optical
Original Articles : Ecology of Otters and Utilization of Artificial Holts in the Ecosystem Conservation Region of the Seomjin River
환경생물학회지(환경생물), 2006
Applied Microscopy, 2018
Immunoelectron microscopy using an antigen-antibody reaction in an electron microscope is a very ... more Immunoelectron microscopy using an antigen-antibody reaction in an electron microscope is a very useful tool to identify the components of a tissue in an electron microscope. Many researchers also use immunoelectron microscopy. Nonetheless, immunoelectron microscopy is rarely introduced systematically, and immunoelectron microscopy can be carried out without fully understanding the principles, and cases of poor understanding can often be seen in the vicinity. Therefore, in order to make it easier to understand, we will first introduce the principles of immunoelectron microscopy and describe practical methods.
Morphological Comparison of Spermatozoa in the Korean Greater Horseshoe Bat (Rhinolophus ferrumequinum korai) and Long-Fingered Bat (Miniopterus schreibersi fuliginosus)
Applied Microscopy, 1999
The aim of the present study was to investigate with transmission electron misroscope the compara... more The aim of the present study was to investigate with transmission electron misroscope the comparative morphology of epididymal spermatozoa in two species of the Korean insectivorous bats belonging to 'prolonged sperm storage' type (Rhinolophus ferrumequinum korai) and 'delayed implantation' type (Miniopterus schreibersi fuliginosus). Sperm head of the R. ferrumequinum korai was bullet shaped and that of M. schreibersi fuliginosus was spatula shaped. The nuclei of the sperm head of the R. ferrumequinum korai and M. schreibersi fuliginosus occupied two-third and a half of it, respectively. The segmented columns of R. ferrumequinum korai were about 12 to 14 in number, and those of the M. schreibersi fuligincsus were about 10 to 12. Particularly, a pile of the satellite fibers in middle piece of R. ferrumequinum korai remained the inner aspect of the outer dense fibers, but those of the M. schreibersi fuliginosus were not.
국내 플라워샵 판매현황에 관한 연구 －품목별 판매율이 높은 화훼상품과 성수기를 중심으로－
Journal of People, Plants, and Environment, 2020
Background and objective: This study was conducted to investigate the effect of an agro-healing p... more Background and objective: This study was conducted to investigate the effect of an agro-healing program on the relationship satisfaction and emotional change between parents and children. Methods: We sent an official letter to D Office of Education with information and recruitment for the agro-healing program. Then D Office of Education has sent the official letter to elementary schools under the jurisdiction to recruit parents who were willing to participate in the programs with their children. The subjects were recruited by order of application, and 27 families participated, but 20 parent-child teams who attended all sessions and fully participated in the program were ultimately selected. From October 12 to November 16, 2019, a total of 6 sessions of the programs were held once a week at a care farm in Gyeongsangbuk-do. In the morning, they participated in a program that utilizes the resources of plants and animals in the care farm, and later participated in an indoor horticultural program in the afternoon. Results: In the parent-child relationship satisfaction test, it was found that communication was significantly increased after participating in the agro-healing program (p = .047). There were no statistically significant changes in the sentence completion tests written by the children, but their potential perception or attitude towards their parents changed more positively than before according to the content of the sentences. Conclusion: The agro-healing program could strengthen the relationship between parent and child by improving the parent-child relationship satisfaction and children's emotional attitude towards their parent.
Korean Journal of Nature Conservation, 2016
We investigated the mammals in Mt. Yeonin, Gyeonggi-do. A total of 20 species belongings 11 Famil... more We investigated the mammals in Mt. Yeonin, Gyeonggi-do. A total of 20 species belongings 11 Familes, 6 Oders, were identified in the survey area. The confirmed mammal is Erinaceus amurensis,
Korean Journal of Nature Conservation, 2011
This study was conducted to identify the distribution characteristics of small village wetlands i... more This study was conducted to identify the distribution characteristics of small village wetlands in Geumsan County, an inland mountain zone, and comparing with Seocheon County, a coastal plain area with different ecological environment characteristics. Using Arc-GIS (v10.1) the village wetland code was extracted to derive the possible location of the village wetland, and the final distribution of the village was obtained by performing indoor judging work based on satellite images, aerial photographs, topographical maps, Korea Land Information System (KLIS), land use level, land cover degree (division), and land use status by local surveying and indoor analyzing. Although Geumsan County (576.66km2) is more than 60% larger than Seocheon County (358.04km2), 607 villages in Geumsan County and 570 villages in Seocheon County are capable of making similar levels of 106.5% of wetlands, but only a fraction of those in Seocheon County were found to be 67.6%. The density of the village wetlands was much lower than that of Seocheon County, a coastal plain area, because there were many mountainous areas in Geumsan County, and most of the wetlands temporarily created for water supply were removed during the analysis phase of the Jeongsa Image, so the actual wetlands of the village were judged to be only two-thirds different from those of Seocheon County.
Reduction Effect Analyses of Particulate Matter Emissions from Buildings by Fuel Cell Systems Combined with Absorption Chiller-Heaters
Journal of The Korean Society of Living Environmental System, 2018
Computational Intelligence and Neuroscience, 2020
We propose three quality control (QC) techniques using machine learning that depend on the type o... more We propose three quality control (QC) techniques using machine learning that depend on the type of input data used for training. These include QC based on time series of a single weather element, QC based on time series in conjunction with other weather elements, and QC using spatiotemporal characteristics. We performed machine learning-based QC on each weather element of atmospheric data, such as temperature, acquired from seven types of IoT sensors and applied machine learning algorithms, such as support vector regression, on data with errors to make meaningful estimates from them. By using the root mean squared error (RMSE), we evaluated the performance of the proposed techniques. As a result, the QC done in conjunction with other weather elements had 0.14% lower RMSE on average than QC conducted with only a single weather element. In the case of QC with spatiotemporal characteristic considerations, the QC done via training with AWS data showed performance with 17% lower RMSE tha...
Journal of Korea Society for Plants People and Environment, 2017
The purpose of this study is to look into the effect of a horticultural activity program on caree... more The purpose of this study is to look into the effect of a horticultural activity program on career women's job satisfaction. As the research subject, this study set 37 career women of 6 occupational clusters, such as elementary school teachers, nurses, social workers, care teachers, and police officers in 'P' city, and financiers in 'D'city. The horticultural activity program was applied for about 10 months from June 2013 to April 2014, and for each job group the program was executed once a week and a total of 8 sessions. As a result of the analysis of job satisfaction by conducting horticultural activity by 6 occupational cluster, occupational clusters like an elementary school teacher, and social worker showed a significant improvement in job satisfaction immediately after horticultural activity was conducted, and in 4 weeks after that, all 5 occupational clusters but a care teacher cluster were found not to show a significant difference. It is expected that various horticultural activity programs would provide emotional stability to working women and consequently improve their overall quality of life. As a result of the above research, this study confirmed that improvement in job satisfaction is more effective when a person steadily participates in gardening activity rather than doing gardening activity temporarily. In addition, this study confirmed that gardening activity could be an alternative remedy which provides a positive change to a career woman's job satisfaction.
Study on the contribution ratios of particulate matter emissions in differential provinces concerning condensable particulate matter
Energy & Environment, 2019
This study attempted to reanalyze the emission property of particulate matter and set up the stra... more This study attempted to reanalyze the emission property of particulate matter and set up the strategy on the emission reduction of particulate matter by considering the condensable particulate matter additionally as the total particulate matter together with filterable particulate matter. For this, total suspended particles and particulate matter 2.5 emitted in 2013 were selected as pollutants. Fuel classifications were divided into major and minor categories, and the sources were divided into major, medium, and minor categories. Three provinces were set as administrative areas: Gyeonggi-do, Chungcheongnam-do, and Jeollanam-do. The condensable particulate matter emission factors used were obtained from National Institute of Environmental Research. The condensable particulate matter emission factors of liquefied natural gas, diesel, and bunker C oil were measured in boilers with no preventive facilities, and the coal power plant emission factor was obtained at the end of the prevention facility. The condensable particulate matter emissions were calculated by multiplying the particulate matter 2.5 filterable particulate matter emissions by the ratio of the condensable particulate matter emissions to the filterable particulate matter of the National Institute of Environmental Research data. Different patterns of emission sources were observed for each province depending on the consideration of condensable particulate matters. Considering only the filterable particulate matters, the proportion of mobile pollutants was high. On the other hand, considering the condensable particulate matters, the contribution of the nonindustrial combustion category emissions using gaseous fuels, such as city gas, increased in the metropolitan area, whereas the contributions of the manufacturing combustion category emissions increased in the nonmetropolitan areas. Therefore, in the case of collecting energy facilities and the manufacturing burning facilities planned in the local cities in Korea, it is necessary to consider the filterable particulate matter, and condensable particulate matter emission amount.
Journal of People Plants and Environment, 2017
As a result of inquiring into the analysis consequent on a symptom by research subject, it was fo... more As a result of inquiring into the analysis consequent on a symptom by research subject, it was found that there were 1 paper (1.5%) which did research for the purpose of rehabilitation of the general public, 26 papers (38.8%) targeting diagnosis-related groups (DRG), and 40 papers (59.7%) targeting social consideration subject. Also, as a result of the inquiry about the frequency & number of times of horticultural therapy program implementation, it was found that 49 papers (73.1%) implemented one time a week, and 45 papers (67.2%) were surveyed as the highest by conducting a total of 11~20 sessions of horticultural therapy programs, In the analysis of horticultural therapy activities by type, plant cultivation activity was found to be the most 506 times, accounting for 41.5%, followed by 297 time crafts activity (24.4%), 213 time floral decoration activity (17.5%), and 203time others activities (16.7%). In cultivation activity, soil-using cultivation activity (25.1%) was found to be lower than the proportion (74.9%) of soiless cultivation (16.4%), crafts activity (24.4%), floral decoration activity (17.5%) and other activities (16.7%). The most used plants in a restricted place like a hospital were found to be in the order of Hedera helix, Chamaedorea elegans, Succulent plant, Syngonium podophyllum, Neofinetia falcata HU, Hoya carnosa (L.f.) R.Br.), Rosmarinus officinalis, and Spathiphyllum spp.
Tuberculosis and Respiratory Diseases, 2009
Pulmonary papillomas are rare benign epithelial neoplasms arising in bronchial surface epithelium... more Pulmonary papillomas are rare benign epithelial neoplasms arising in bronchial surface epithelium. They are categorized by a variety of cell types including squamous, glandular, and mixed squamous and glandular type. Among them, glandular papilloma is extremely rare and has not been reported in Korea. The patient was a 52 year-old man presenting with a 4-months' history of recurrent hemoptysis. Bronchofiberoscopy revealed a whitish, glistening, and polypoid mass lesion at the proximal bronchus in the basal segment of the left lower lung. Bronchoscopic biopsy was performed; papillary fronds lined by ciliated or nonciliated pseudostratified columnar epithelium were noted on histologic findings. We present the first case of glandular papilloma in Korea. Two years later, the patient visited our hospital again due to hemoptysis. On follow-up bronchoscopy, a mass that had been found previously showed an increase in size.
P-23: Design Parameters for Using Charging Technique for TFT-LCDs
SID Symposium Digest of Technical Papers, 2007
In case of charging a large capacitor in a short time, We use a well-known pre charging technique... more In case of charging a large capacitor in a short time, We use a well-known pre charging technique(1), which is a method of charging a pixel two times at an interval of one gate pulse width. But there is a side effect of a pattern looking like out of focus. This phenomenon is caused directly by a different quantity of charging being introduced into two pixels which are two pixels apart vertically with each other. To remove this side efeect, we optimize the charging design parameter; Cst+Clc, Ion condition from TFT device. with the pre charging technique, A 120Hz 32″ WXGA TFT-LCD which has three times of Cst + Clc as compared to conventional IPS structure has been developed.
During the last 10 years, there have been many efforts in some areas of Natural Language Processi... more During the last 10 years, there have been many efforts in some areas of Natural Language Processing to encode the normal text or documents into machine readable form. If we encode written data using a canonical form which can be recognized by a computer, we can extract needed information and process and utilize it for another purposes. From this point of view, we present an account of the encoding of a printed dictionary. The construction of a lexicon is very time-consuming and expensive work and the application of the lexicon is restricted. In this paper, we describe a logical structure for Korean printed dictionaries as a general lexical representation based on SDML, which can be transformed into another representation for different application requirements.
Fabrication and Properties of Flexible OLEDs on Polyimide-Graphene Composite Film Substrate
Molecular Crystals and Liquid Crystals, 2013
ABSTRACT
Journal of the European Ceramic Society, 1992
C3H 8 was added in order to obtain stoichiometric ~3-SiC in the MTS + H 2 CVD system. The experim... more C3H 8 was added in order to obtain stoichiometric ~3-SiC in the MTS + H 2 CVD system. The experiments were carried out by using a cold-wall reactor under atmospheric pressure in the temperature range 1100-1500C. XRD, Vickers microhardness tester and SEM were used in characterizing the stoichiometry and morphology, hi the absence of C3H s the tenlperature required jor the deposition ()[" stoichiometric SiC was above 1500 ° C, otherwise excess Si was codeposited with SiC. With C3H8 addition, however. stoichiometric SiC could be obtained even at temperatures as low as 1200C and the pr¢lerred orientation was changedJi'om (220) to (111). The mierostructure and har~hless value were related to the pre/'erred orientation and stoichiometrv of the coathTg layers, re,v~ectively.
Journal of the American Ceramic Society, 2005
The effects of microstructure and residual stress on the mechanical properties of Si 3 N 4-based ... more The effects of microstructure and residual stress on the mechanical properties of Si 3 N 4-based three-layer composite materials were investigated. The microstructure of each layer was controlled by the addition of two differently sized silicon carbides: fine SiC nanoparticles (∼200 nm) or relatively large SiC platelets (∼20 µm). When the SiC nanoparticles were added, the average grain size of Si 3 N 4 was reduced because of the inhibition of grain growth by the particles. On the other hand, when the SiC platelets were added, the microstructure of Si 3 N 4 was not much changed because of the large size of the platelets. Three-layer composites were fabricated by placing the Si 3 N 4 /SiCnanoparticle layers on the surface of the Si 3 N 4 /SiC-platelet layer. The residual stress was controlled by varying the amount of SiC added. The mechanical properties of threelayer composites with various combinations of microstructure and residual stress level were investigated.
Journal of the American Ceramic Society, 2005
Si 3 N 4 ceramics reinforced with SiC platelets were fabricated by hot pressing at 1800°C. The mi... more Si 3 N 4 ceramics reinforced with SiC platelets were fabricated by hot pressing at 1800°C. The microstructure of the Si 3 N 4 matrix itself was the same with or without the addition of the SiC platelets. However, the mechanical properties of the Si 3 N 4 were changed remarkably by the SiC addition. The fracture toughness and the crack resistance with crack propagation (R-curve behavior) were improved while the fracture strength was decreased slightly by the platelets. Improvement in crack resistance was attributed to the extensive interaction of cracks with the platelets. The reduction in strength, on the other hand, is believed to be due to cracks associated with weak platelet-matrix interfaces.
Growth of silicon carbide by chemical vapour deposition
Journal of Materials Science Letters, 1991
Silicon carbide (SIC) has some oustanding properties such as high hardness, chemical inertness an... more Silicon carbide (SIC) has some oustanding properties such as high hardness, chemical inertness and thermal stability. These properties have attracted great interest in its structural and device use, especially at high temperature. Since Pring and Fielding [1] synthesized SiC by chemical vapour deposition (CVD) using C6H 6 and SiC14 as a precursor, many efforts [2-5] have been made to investigate the precursors of Si and C. Recently methyltrichlorosilane (MTS; CH3SiC13)has been the most frequently used precursor [6-8], because MTS contains the same number of Si and C atoms and thus can easily produce stoichiometric SiC. From thermodynamic calculations on the CVD of SiC in the MTS + H2 system, Kingon et al. [9] developed CVD phase diagrams and reported that only SiC single phase can be deposited in a wide range of temperature and MTS molar fraction. However, in experimental works by others it has been reported that excess Si [10] or excess C [11] is codeposited with SiC under some conditions, and relatively strict control in the deposition conditions is required for the stoichiometric growth of SiC. In this work we examined the stoichiometric growth of SiC in the MTS + H2 system, and obtained SiC films without Si or excess C phases at a temperature of 1500 °C, but excess Si phase was always observed at <1500 °C. For the deposition experiment we used a conventional horizontal cold-walled reactor which consisted of a quartz tube (inside diameter 26 mm) and a SiC-coated graphite susceptor heated by r.f. induction. The MTS vapour was carried by H2 from an MTS container which was maintained at 0 °C. The molar fraction of MTS was controlled by adjusting the flow rate of carrier gas. The temperature of the substrate, located on a tilted susceptor, was measured with an optical pyrometer calibrated with SiC emissivity [12]. The detailed experimental conditions are listed in Table I. The film thickness was measured by gravimetry and identified by optical
Original Articles : Ecology of Otters and Utilization of Artificial Holts in the Ecosystem Conservation Region of the Seomjin River
환경생물학회지(환경생물), 2006