• The Mathematical Education
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• v.24 no.2
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• pp.48-73
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• 1986

Though the tradition of Korean mathematics since the ancient time up to the 'Enlightenment Period' in the late 19th century had been under the influence of the Chinese mathematics, it strove to develop its own independent of Chinese. However, the fact that it couldn't succeed to form the independent Korean mathematics in spite of many chances under the reign of Kings Sejong, Youngjo, and Joungjo was mainly due to the use of Chinese characters by Koreans. Han-gul (Korean characters) invented by King Sejong had not been used widely as it was called and despised Un-mun and Koreans still used Chinese characters as the only 'true letters' (Jin-suh). The correlation between characters and culture was such that, if Koreans used Han-gul as their official letters, we may have different picture of Korean mathematics. It is quite interesting to note that the mathematics in the 'Enlightenment Period' changed rather smoothly into the Western mathematics at the time when Han-gul was used officially with Chinese characters. In Koryo, the mathematics existed only as a part of the Confucian refinement, not as the object of sincere study. The mathematics in Koryo inherited that of the Unified Shilla without any remarkable development of its own, and the mathematicians were the Inner Officials isolated from the outside world who maintained their positions as specialists amid the turbulence of political changes. They formed a kind of Guild, their posts becoming patrimony. The mathematics in Koryo significant in that they paved the way for that of Chosun through a few books of mathematics such as 'Sanhak-Kyemong', 'Yanghwi-Sanpup' and 'Sangmyung-Sanpup'. King Sejong was quite phenomenal in his policy of promotion of mathematics. King himself was deeply interested in the study, createing an atmosphere in which all the high ranking officials and scholars highly valued mathematics. The sudden development of mathematic culture was mainly due to the personality and capacity of king who took anyone with the mathematic talent into government service regardless of his birth and against the strong opposition of the conservative officials. However, King's view of mathematics never resulted in the true development of mathematics perse and he used it only as an official technique in the tradition way. Korean mathematics in King Sejong's reign was based upon both the natural philosophy in China and the unique geo-political reality of Korean peninsula. The reason why the mathematic culture failed to develop continually against those social background was that the mathematicians were not allowed to play the vital role in that culture, they being only the instrument for the personality or politics of the king. While the learned scholar class sometimes played the important role for the development of the mathematic culture, they often as not became an adamant barrier to it. As the society in Chosun needed the function of mathematics acutely, the mathematicians formed the settled class called Jung-in (Middle-Man). Jung-in was a unique class in Chosun and we can't find its equivalent in China or Japan. These Jung-in mathematician officials lacked tendency to publish their study, since their society was strictly exclusive and their knowledge was very limited. Though they were relatively low class, these mathematicians played very important role in Chosun society. In 'Sil-Hak (the Practical Learning) period' which began in the late 16th century, especially in the reigns of Kings Youngjo and Jungjo, which was called the Renaissance of Chosun, the ambitious policy for the development of science and technology called for. the rapid increase of he number of such technocrats as mathematics, astronomy and medicine. Amid these social changes, the Jung-in mathematicians inevitably became quite ambitious and proud. They tried to explore deeply into mathematics perse beyond the narrow limit of knowledge required for their office. Thus, in this period the mathematics developed rapidly, undergoing very important changes. The characteristic features of the mathematics in this period were: Jung-in mathematicians' active study an publication, the mathematic studies by the renowned scholars of Sil-Hak, joint works by these two classes, their approach to the Western mathematics and their effort to develop Korean mathematics. Toward the 'Enlightenment Period' in the late 19th century, the Western mathematics experienced great difficulty to take its roots in the Peninsula which had been under the strong influence of Confucian ideology and traditional Korean mathematic system. However, with King Kojong's ordinance in 1895, the traditional Korean mathematics influenced by Chinese disappeared from the history of Korean mathematics, as the school system was hanged into the Western style and the Western mathematics was adopted as the only mathematics to be taught at the Schools of various levels. Thus the 'Enlightenment Period' is the period in which Korean mathematics shifted from Chinese into European.

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1083-1093
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• 1997

Background : So far, there have been numerous reports on organ damage due to cryptococcosis, however, cases of lung localization have been infrequently reported. Recently pulmonary cryptococcosis has been reported more frequently than before due to enhanced diagnostic techniques and increased underlying diseases. Method : The author, therefore, analyzed the clinical manifestations of 5 cryptococcosis cases that we experienced at Hanyang University Hospital from 1985 to 1996 and 9 cases reported in Korea from 1984 and 1996 retrospectively. The following results were obtained. Results : Cryptococcosis occurred frequently over sixth decade and the male to female ratio was 3.6 : 1. Underlying diseases included acute rejection after kidney transplantation, rheumatoid arthritis, autoimmune hepatitis, diabetes mellitus and state of bilateral adrenalectomy. Remaining 8 cases had no evidence of an underlying disease. Because the symptoms were subacute & nonspecific, and not improved by conventional antibiotics, 6 patients of 14 pulmonary cryptococcosis patients were treated as pulmonary tuberculosis before correct diagnosis was made. There were three asymptomatic cases. According to the results of CXR, solitary alveolar consolidation was the most common finding(8 cases) followed by diffuse infiltration(5 cases). It also showed pleural effusion, hilar lymphadenopathy and cavity formation that was rarely reported in world literature. The diagnasis was made through fine needle aspiration biopsy in 10 cases, open thoracotomy in 2 cases, transbronchial lung biopsy in 1 case. and thoracentesis with pleural biopsy in 1 case. Only one case showed positive result in sputum stain and culture, serum latex agglutination test for cryptococcus neoformans. Treatment modalities were various such as fluconazole, amphotericin B, flucytosine, ketoconazole, surgery and it's combination. After 1990 year, there was a trend that fluconazole or ketoconazole are more used than other therapeutic modalities. Conclusion : Because the symptoms are subacute & nonspecific and not improved by conventional antibiotics, pulmonary cryptococcosis is likely to misdiagnosis as pulmonary tuberculosis in Korea. Because the diagnosic yield of sputum stain, culture and serologic test for pulmonary cryptococcosis is low, histologic diagnosis is need in most pulmonary cryptococcosis.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.899-906
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• 1997

Background : The percutaneous pleural needle biopsy have been regarded as cornerstone in the diagnosis of lymphocyte dominant pleural effusions of which acid fast bacilli smear and cytologic exam was negative. However, the complications of percutaneous pleural needle biopsy is not rare and its diagnostic efficacy is not always satisfactory. Recently, pleural fluid adenosine deaminase (ADA) and carcinoembryonic antigen (CEA) are widely accepted as markers of tuberculous pleurisy and malignant pleural effusion respectively. We designed this study to re-evaluate the role of percutaneous pleural needle biopsy in the diagnosis of lymphocyte dominant exudative pleural effusions whose AFB smear, cytologic exam was negative. Method : Retrospective analysis of 73 cases of percutaneous pleural needle biopsy in case of lymphocyte dominant exudative pleural effusions whose AFB smear and cytoloic exam was negative from Jan 1994 to Feb 1996 was done. Result : In 35 cases, specific diagnosis was obtained(all cases were tuberculous pleurisy), and in 30 cases specific diagnosis was not obtained in spite of getting adequate pleural tissues, and in the other 8 cases, percutaneous pleural biopsy failed to get pleural tissues. In 9 cases, complications were combined including pneuomothorax and hemothorax. All 49 cases of pleural effusions whose ADA value was higher than 40IU/L and satisfying other categories were finally diagnosed as tuberculous pleurisy, however, the pleural biopsy confirmed only 28 cases as tuberculous pleurisy. In 6 cases of pleural effusions of which CEA value is higher than 10ng/ml, the pleural biopsy made specific diagnosis in no case. Final diagnosis of above 6 cases consisted of 4 malignant effusions, 1 malignancy associated effusion and 1 tuberculous pleurisy. Conclusion : In the diagnosis of 73 cases of lymphocyte dominant pleural effusions of which acid fast bacilli smear and cytologic exam was negative, percutaneous pleural biopsy diagnosed only in 35 cases. In the diagnosis of tuberculous pleurisy, the positive predictive value of higher ADA than 40 IU/L in lymphocyte dominant pleural effusion with negative AFB smear and negative cytologic exam was 100%. And the diagnostic efficacy of pleural biopsy was 57%. In cases of effusions with high CEA than 10ng/ml 83% and 0% respectively. Finally, we concluded that percutaneous pleural needle biopsy in the diagnosis of AFB smear negative and cytologic exam negative lymphocyte dominant exudative pleural effusion was not obligatory. especially in effusions with high ADA and low CEA value.

• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.17-26
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• 2002

Background : The detection and early elimination of the causes for acute respiratory distress syndrome(ARDS) at the initial stage can result in a more favorable prognosis. Miliary tuberculosis as a cause of the ARDS is quite rare. A diagnosis of miliary tuberculosis is difficult due to the diversity of radiological patterns and non-specific clinical finfings, and low sensitivity of sputum examinations for acid-fast bacilli(AFBs). An analysis of the clinical data is the first step in diagnosing these unusual, rare cases. Materials and Methods : In this study the clinical features, laboratory data, radiological findings and diagnostic methods were analyzed in 9 cases with an initial presentation of ARDS due to miliary tuberculosis. The ARDS was defined by the definition of the American-Europian consensus conference 1992. Results : The mean age of the patients was $67{\pm}18$ years (F:M=7:2). The chief complaints were dyspnea(5/9), coughing (3/9) and fever(5/9). On a physical examination, fine or coarse crackles were noted(6/9). The ARDS developed on average 6.7 days after the initial respiratory symptoms. The mean $PaO_2/FiO_2$ of the patients was $133.5{\pm}53.4$, the number of cases with a WBC<5000/$mm^3$ was 4 out of 9 cases. A platelet count<70,000/$mm^3$ was observed in 2 out of 9 cases, and the serum albumin level was $2.6{\pm}0.6$ g/dL. The initial simple chest PA showed ground glass appearances and consolidation in all cases, However, the miliary nodular densities were observed in only 4 out of the 9 cases. HRCT revealed alveolar densities and a consolidation in 5 out of 6 cases, and miliary nodules in 5 out of 6 cases, The diagnosis of tuberculosis was made by a liver biopsy (4/4, 100% sensitivity), a bone marrow biopsy (1/2, 50% sensitivity), and an open lung biopsy (1/1), the sputum AFB was positive in only 2 out of 9 cases. The patient was treated with INH, RFP, EMB, PZA, and steroids. The survival rate was 55.5%. Conclusion : Miliary tuberculosis should be considered as one of the causes for ARDS in areas where there is a high prevalence of tuberculosis. The chief complaints of the patients on admission are dyspnea, fever and coughing without any specific riskfactors. A liver biopsy is particularly useful in ARDS patients with mechanical ventilation to determine the causes of the ARDS if miliary tuberculosis is suspected as being the underlying disease.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.411-418
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• 2004

Background : Cigarette smoking is the single biggest avoidable cause of death and disability in most countries. Effective prevention of cigarette Smoking and help for those wishing to quit can therefore yield enormous health benefits for populations and individuals. Although most of smokers try to stop smoking for themselves, the success rate of quitting smoking is very low. Promoting and supporting smoking cessation should be an important health policy priority for healthcare professionals in all clinical settings. In this study, we tried to evaluate the effect of the educational program for smoking cessation of our hospital, the smoking pattern, and characteristics of adult smokers enrolled in the program. Methods : We enrolled 640 smokers, who has visited the '5 day stop smoking school' for smoking cessation from Jan 1998 to 2001. we evaluated the characteristics of the smokers based on the self report questionnaire at the beginning of the program and we also checked 100 smokers, enrolled in Inpatient Smoking Cessation Educational program, their smoking behavior and the cessation rate with postal questionnaire after finishing this program from Nov 2002 to Jan 2003. Results : The health was most common motivation for smoking cessation. The stress was the most important motivation of smoking. The overall smoking cessation rate of the smokers enrolled in inpatient smoking cessation school was 60%. The age of starting smoking and the kind of occupation have a significant difference between the success group and failure group of smoking cessation. Conclusion : The inpatient smoking cessation program was effective smoking cessation intervention in the adult smokers who enrolled in '5 day stop smoking school'.

• Tuberculosis and Respiratory Diseases
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• v.64 no.2
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• pp.109-124
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• 2008

Background: The incidence of chronic obstructive pulmonary disease (COPD) is increasing and the disease is becoming an important cause of morbidity and mortality worldwide. It is important to implement evidence-based guidelines by primary care physicians (PCPs) to establish qualified management of COPD patients. The aim of this survey is to investigate the pattern of COPD management among PCPs and to apply it to the development of Korean COPD guidelines. Methods: A web-based questionnaire was prepared that consisted of 25 questions on the pattern of COPD management. A total of 217 PCPs participated in the survey from June 2006 to May 2007. Results: Many PCPs (61.8%) possessed a spirometer, but the application rate was relatively low (35.8%) and more than half of the COPD patients (57%) did not receive a diagnosis based on spirometry. Administration of oral medication was preferred than the administration of inhaled medication for both stable COPD and acutely exacerbated COPD. More than 90% of the PCPs endorsed educational measures to quit smoking and vaccinate against influenza. It was noted that 56.7% of the PCPs were aware of the GOLD guidelines, but only 7.3% tended to fully implement the recommendations of the guidelines in daily practice. Conclusion: The results of the survey indicate that despite the high awareness rate of the current COPD guidelines, deficits exist among the PCPs with respect to the diagnosis and treatment of COPD. The results of this survey should be applied for the development of new COPD guidelines in order to decrease the discrepancy between the guidelines and the daily practice of the PCPs.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.358-363
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• 2014

BACKGROUND: Many strawberry growers are utilizing daylength extension by using incandescent bulb or fluorescent lamp to break dormancy of strawberry induced by low temperature and short day conditions. Conventional incandescent bulb and fluorescent lamp consume a lot of electricity and have short longevity. Red light known for most efficient wavelength for daylength extension light of short-day plant and long-day plant. This study was conducted to verify the effects of red light to enhance growth and to increase production of strawberry (Fragaria ${\times}$ ananassa Duch. cvs. "Seolhyang") METHODS AND RESULTS: Three red light (660nm) of 0.70, 0.87, and $1.05{\mu}mol/m^2/s$ (PAR) and conventional incandescent bulb of 40 Lux were treated respectively under the pot experiment. All treatment irradiated from 18:00 to 24:00 for 6 hours. Red light treatment tend to increase leaf stem number, flower stem number, weight of flower stem, crown weight, root weight, and leaf area of strawberry then incandescent bulb treatment. In field experiment, red light of $0.7{\mu}mol/m^2/s$ (PAR) and conventional incandescent bulb of 40 Lux were irradiated respectively. Field experiment showed that the leaf number, leaf weight, and crown weight of strawberry increased than those of incandescent bulb control with red LED of $0.7{\mu}mol/m^2/s$ (PAR). Red LED treatment increased the fruit number over 15g than incandescent bulb. Furthermore, red LED treatment decreased fruit number below 15g of strawberry than incandescent bulb treatment. Therefore, We believed that red LED treatment increased marketable fruit number by increment of weight of each fruit. Consequently, marketable fruit number, fruit weight, and fruit production of strawberry were increased than those of incandescent bulb by 5 %, 2.9 %, and 8.5 % respectively, but not showed significantly differences. CONCLUSION: These results presumably due to directly enhanced photosynthesis of strawberry leaves and activated action of Pfr phytochrome form by red light. In conclusion, red LED of 660nm could be used for daylength extension light source to enhance production of strawberry.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.327-333
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• 2014

BACKGROUND: Rabbiteye blueberry(Vaccinium ashei) is one of the most widely grown blueberry types in the world, together with Northern and Southern highbush blueberry(Vaccinium corymbosum). Rabbiteye blueberry have higher soil adaptability and fruit productivity but less cold tolerance to low temperature than highbush blueberry. The objective of this study is to investigate freezing tolerance of floral buds and establish a cultivation zone for rabbiteye blueberry cultivars. METHODS AND RESULTS: Bearing branches which have similar thickness and same number of floral buds were collected in the early January at the blueberry germplasm preservation plot located in Namhae Sub-station, National Institute of Horticultural and Herbal Science in Gyeongsangnamdo. Cold response of bearing branches were investigated by electrolyte leakage and freezing tolerance of floral buds were determined by ovary browning ratio of 50%($LT_{50}$). Cultivation zone was established based on mean annual extreme minimum temperature for 30 years, from 1981 to 2010. The electrolyte leakage of bearing branches in rabbiteye blueberry increased as temperature decreased and was lowest in 'Brightwell' but highest in 'Bluegem' when they were kept in $-5^{\circ}C$. Besides, the electrolyte leakage increased in 'Brightblue', 'Brightwell', 'Climax', 'Delite', 'Gardenblue', 'Southland' and 'Woodard' in $-20^{\circ}C$. Freezing tolerance($LT_{50}$) was lowest in 'Bluegem' and 'Homebell'($-13.3^{\circ}C$), and highest in 'Tifblue'($-25^{\circ}C$) among different rabbiteye blueberry cultivars. $LT_{50}$ of 'Southland' was from -15.0 to $-16.7^{\circ}C$, that of 'Delite', 'Brightwell',' Austin' and 'Climax' was $-18.3^{\circ}C$, and that of 'Bluebelle', 'Woodard' and 'Powderblue' was $-20^{\circ}C$. CONCLUSION: This study indicate that The hardiness zones of rabbiteye blueberry were classified into Six cultivation zones and cultivation zones of most cultivars were the south of Jeollanam-do and Gyeongdangnam-do, except for 'Tifblue.'

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.395-402
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• 2014

BACKGROUND: Azadirachta indica Extract(AIE) containing azadirachtin as active ingredient have been used worldwide as environment-friendly organic material having pest control properties. However, the extracts prepared with different solvent and from different plant site is very diverse and have different toxicity. METHODS AND RESULTS: In this study, the four week repeated oral dose toxicity test of aqueous AIE in Sprague-Dawley rats was carried out to investigate the toxic effect of liver, main toxicity target organ of AIE. The male and female rats were divided into 4 groups, respectively; control(0 g/Kg bw), low-dose group(0.5 g/Kg bw), middle-dose(1.0 g/Kg bw) and high-dose group(2.0 g/Kg bw). As a results, relative liver weight increased with dose-dependent of AIE(p<0.05). Serum LDH in all AIE-treated groups were significantly lower than the control in male rats(p<0.05). However, serum GOT and GPT were significantly increased in all male AIE-treated groups in male rats(p<0.05) and, in particular, increase of serum GPT in dose-dependent manner raise the possibility of liver damage. Even through serum GLU was increased significantly in high-dose group in male rats compared to control, there were no significant differences of urinary GLU among all groups(p<0.05). In addition, histopathological examination of the liver did not reveal any lesions in all AIE-treated groups. CONCLUSION: In conclusion, 4 weeks of the repeated oral administration of AIE 2.0 g/Kg to rats has resulted no toxic response in liver. Therefore, AIE was no indicated to have any toxic effect in the SD rats, when it was orally administrated below the dosage 2.0 g/Kg/day for 4weeks.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.24-34
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• 2013

BACKGROUND: This study was carried out to compare population size of mudfish (Misgurnus mizolepis) between the agricultural practices and to investigate the causes of its differences. We also provided basic information for sustainable use of mudfish population in paddy fields. METHODS AND RESULTS: Mudfish and benthic invertebrates which are diet of mudifish were investigated from 8 sites of organic and conventional rice paddy fields in South Korea. Total number of mudfish were 1,882 individuals in survey sites. Mudfish population were 2.4 times larger in organic paddy fields (1,333 individuals) than in conventional paddy fields (549 individuals). The population size of mudfish was larger in Mungyeong-si, Gyeongsangbuk-do and Anseong-si, Gyeonggi-do with relatively better environmental conditions than the other 5 sites including Suwon-si, Gyeonggi-do, Cheongyang-gun, Chungcheongnam-do, Gunsan-si, Jeollabuk-do, Gimje-si, Jeollabuk-do, Hwasun-gun, Jeollanam-do, Hamyang-gun, Gyeongsangnam-do. Benthic invertebrates collected from survey sites were 74 species, 68 genera, 46 families, 19 orders, 6 classes and 3 phyla. According to agricultural practices, benthic invertebrates were identified 66 species, 62 genera, 41 families, 17 orders, 6 classes and 3 phyla in organic paddy fields while there were 66 species, 60 genera, 42 families, 18 orders, 6 classes and 3 phyla in conventional paddy fields. Dominant invertebrates were Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. There were no differences in dominant species between organic and conventional paddy fields. Population size of mudfish tended to increase with the population size of Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. But, only population of Chironomidae sp. and Copepoda sp. statistically related to population size of mudfish. The number of individuals of mudfish (Misgurnus mizolepis) was higher at the low rate of urban area than any other surveyed region and was affected by appearance ratio of main preys such as Chironomidae sp. and Ostracoda sp. CONCLUSION(S): The population size of mudfish in rice paddy fields could be affected by environmental conditions and agricultural practices such as organic and conventional methods.