• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.279-286
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• 2013

BACKGROUND: Soil incorporation of green manure crop(GMC) is one of the methods for reducing continuous cropping injury and increasing yield of carrot. The purpose of this study was to evaluate the effects of green manure crops on growth and yield of carrot for reduction of continuous cropping injury of carrot through crop rotation. METHODS AND RESULTS: To reduce the injury by continuous cropping system(CCS) of carrot cultivation, GMCs such as crotalaria and sudangrass were applied, which GMC was sowed in latter-June and returned to soil in latter-October. Nutrient contributions of N, $P_2O_5$, $K_2O$, CaO, and MgO in crotalaria were 8.3, 7.5, 4.4, 7.8, and 2.1 kg/10a, respectively. Nutrient contributions of N, $P_2O_5$, $K_2O$, CaO, and MgO in sudangrass were 8.4, 8.6, 26.8, 0.3, and 2.7 kg/10a, respectively. After incorporation of GMCs into soil, bulk density in soil with GMCs was lower than that in soil without GMCs(control). In soil after incorporation of GMCs, pH was not different in all treatment conditions, and ranged from 6.37~6.64. EC in soil after incorporation of GMCs was lower than that in soil without GMCs. The OM, T-N, and avail. $P_2O_5$ contents in soil with GMCs were higher than those in soil without GMCs. The growth and yields were increased as 39.2%(6,226 kg/10a) in the rotational cropping system(RCS) as compared to continuous cropping system(control and without NPK) of 4,473 kg/10a. Crotalaria cultivation were the most effective crop for reducing the injury of continuous cropping of carrot. CONCLUSION(S): This study suggest that the RCS using GMCs showed lower disease outbreak density in soil for carrot cultivation as compared to CCS without GMCs. Especially, the GMCs good effect for reduction of continuous cropping injury of carrot.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.1
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• pp.207-244
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• 2015

Aviation safety is the stage in which the risk of harm to persons or of property damage is reduced to, and maintained at or below, an acceptable level through a continuing process of hazard identification and risk management. Many accidents and incidents have been taking place since 2014, while there had been relatively safer skies before 2014. International civil aviation community has been exerting great efforts to deal with these emerging issues, thus enhancing and ensuring safety throughout the world over the years. The Preamble of the Chicago Convention emphasizes safety and order of international air transport, and so many Articles in the Convention are related to the safety. Furthermore, most of the Annexes to the Convention are International Standards and Recommended Practices pertaining to the safety. In particular, Annex 19, which was promulgated in Nov. 2013, dealing with safety management system. ICAO, as law-making body, has Air Navigation Commission, Council, Assembly to deliberate and make decisions regarding safety issues. It is also implementing USOAP and USAP to supervise safety functions of member States. After MH 370 disappeared in 2014, ICAO is developing Global Tracking System whereby there should be no loophole in tracking the location of aircraft anywhere in world with the information provided by many stakeholders concerned. MH 17 accident drove ICAO to install web-based repository where information relating to the operation in conflict zones is provided and shared. In addition, ICAO has been initiating various solutions to emerging issues such as ebola outbreak and operation under extreme meteorological conditions. Considering the necessity of protection and sharing of safety data and information to enhance safety level, ICAO is now suggesting enhanced provisions to do so, and getting feedback from member States. It has been observed that ICAO has been approaching issues towards problem-solving from four different dimensions. First regarding time, it analyses past experiences and best practices, and make solutions in short, mid and long terms. Second, from space perspective, ICAO covers States, region and the world as a whole. Third, regarding stakeholders it consults with and hear from as many entities as it could, including airlines, airports, community, consumers, manufacturers, air traffic control centers, air navigation service providers, industry and insurers. Last not but least, in terms of regulatory changes, it identifies best practices, guidance materials and provisions which could become standards and recommended practices.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.7-13
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• 2006

Plastichouse cultivation for crops and vegetables in the winter has been widely popularized in Korea. In the vinylhouse Ultraviolet B penetration is lower than in the field, and so some problems, as plant overgrowth and outbreak of disease, occurred frequently. The effect of artificial supplement ultraviolet B $(UV-B:280{\sim}320nm)$ radiation on the physiological responses and yield of perilla (perilla frutescens) was investigated UV-B ray was radiated on perilla with the 10th leaf stage at the distance of 90, 120 and 150 cm from the plant canopy for 30 days after planting in the vinylhouse. The production of fresh perilla leaves was high in the order of plastic house, ambient+50% of supplemental UV-B, ambient ambient+100% of supplemental UV-B. Enhanced UV-B radiation affected the intensity of thirty-three proteins in 2-dimensional electrophoretic analysis of proteins and ten proteins out of them seemed to be responsive to UV-B : a protein was, ATP synthase CF1 alpha chain, down regulated and nine proteins (Chlorophyll a/b bindng protein type I, Chlorophyll a/b binding protein type II precursor, Photosystem I P700 chlorophyll a apoprotein A2, DNA recombination and repair protein recF, Galactinol synthase, S-adenosyl-L-methionine, Heat shock protein 21, Calcium-dependent protein kinase(CDPK)-like, Catalase) were up-regulated.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.394-400
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• 2006

Purpose : This study was design and performed for evaluations of resent clinical pattern of bronchiolitis caused by RSV infection with children under 2 year of age for 5 years, who were admitted to pediatric ward. Methods : The inclusion criteria of the patients were children under 24 month-of-age, clinical manifestations of lower respiratory tract infection, and RSV antigen that was detected by a direct immunofluorescence test from the nasal secretions. The additional laboratory and simple chest X-ray findings were reviewed from the medical records of children who were admitted Wonkwang university hospital from Jan. 1999 to Dec. 2003. Results : In the 5 year study duration, 127 patients were enrolled and outbreak of RSV bronchiolitis took place in 2001. The 80 cases(63 percent) of RSV infection were concentrated in later autumn and winter. Number of the cases show coughing were 120(94.5 percent), but rale was audible in 78 cases(61.4 percent). Dyspnea, wheezing, and intercostal retraction were noticed in 27(21.3 percent), 21(16.5 percent), and 4(3 percent) cases respectively. The most common chest X-ray finding was hyperinflation of the lung that was noticed in 110 cases(86.6 percent). Care with mechanical ventilator for more than 2 days required in 5 cases. Conclusion : Lower respiratory tract infection by RSV was common in late autumn and winter season but year-round infection was noticed. The severity of RSV respiratory tract infectiontakes in some degree a grave course. So we suggest that population-based surveillance of acute respiratory infection due to RSV is necessary for assessment of prevalence and epidemiology of this disease.

• Pediatric Infection and Vaccine
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• v.23 no.3
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• pp.172-179
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• 2016

Purpose: Bacillus cereus has been reported as the cause of nosocomial infections in cancer patients. In our pediatric cancer ward, a sudden rise in the number of patients with B. cereus bacteremia was observed in 2013 to 2014. This study was performed to investigate the molecular epidemiology of increased B. cereus bacteremia cases in our center. Methods: Pediatric cancer patients who developed B. cereus bacteremia were identified from January 2001 to June 2014. The B. cereus bacteremia in this study was defined as a case in which at least one B. cereus identified in blood cultures, regardless of true bacteremia. Available isolates were further tested by multilocus sequence typing (MLST) analysis. A retrospective chart review was performed. Results: Nineteen patients developed B. cereus bacteremia during the study period. However, in 2013, a sudden increase in the number of patients with B. cereus bacteremia was observed. In addition, three patients developed B. cereus bacteremia within 1 week in July and the other three patients within 1 week in October, respectively, during emergency room renovation. However, MLST analysis revealed different sequence types without consistent patterns. Before 2013, five tested isolates were ST18, ST26, ST177, and ST147-like type, and ST219-like type. Isolates from 2013 were ST18, ST73, ST90, ST427, ST784, ST34-like type, and ST130-like type. Conclusions: MLST analyses showed variable ST distribution of B. cereus isolates. Based on this study, there was no significant evidence suggesting a true outbreak caused by a single ST among patients who developed B. cereus bacteremia.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.170-175
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• 1997

Purpose : Hemolytic uremic syndrome(HUS), known as a most common cause of childhood renal failure in western countries, has been a relatively rare disease in Korea. Although the reported cases were not related to any specific cause in Korea, there was an outbreak of HUS with bloody diarrhea in Japan last year. We report here that we experienced the several typical HUS last year. Patients : From Jan.1996 to Dec. 1996, five patients were diagnosed as HUS at Samsung Seoul Medical Center, Dept. Pediatrics. Results : 1) The age of onset was below 3 years in 3 cases and above 9 years in 2 cases. 2) All the cases happened between summer and autumn. Three patients had domestic travel and 4 patients drank well or spring water before the symptoms. 3) The clinical manifestation was generalized edema, oliguria, anuria and hematuria. The bloody diarrhea were present in 5 cases and 1 patient had operation with the impression of appendicitis. 4) There was no bacteria which was isolated from the blood or stool samples. 5) Renal biopsies were performed in 2 cases, because of protracted clinical course. One showed microthrombotic angiopathy and the other cortical necrosis with necrotizing glomeruli. 6) Complete recovery was the outcome in 4 cases and one case progressed to chronic renal failure. Conclusion : In conclusion, typical HUS associated with bloody diarrhea, epidemic and good prognosis can be found in Korea and careful surveillance of the pre-clinical cases will be necessary.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.183-192
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• 1982

The variability of rice productivity during last 2 decades (1961-1980) of ten years before and after the introduction of"Tongil" was reviewed from the epochal, regional and varietal points of view. During that period the cultivated area of paddy rice have remained almost unchanged, while the total rice production have got elevated from 3, 463 million metric tons in 1961 to 6.006 million metric tons in 1977, recording 73.4% increase. This remarkable increase in rice production is considered to be attributable much to the development and release of new high yielding variety, "Tongil", coupled with the amelioration of cultural techniques. However, in 1978 Tongil type varieties experienced the epidemic outbreak of blast disease due to the shifted race population of blast fungus and in 1980 recorded poor rice production as low as in 1960's due to the unfavorable weather stress throughout the rice growing season, giving rise to many problems awaiting solutions for securing the stabilized high production of rice. The rice yield has continued the gradual increase during last two decades but its difference between farmer and research organization have got wider from 79kg/10a during 1960 to 1971 to 101kg/l0a during 1972 to 1980, and also the inter-regional differences have been increased from 50-60kg/10a to 80kg/10a during those periods. Therefore, this proves that we have raised the upper boundary of rice yield by increasing the yield potential of rice variety but have not changed those absolute deviations. Estimates indicate that the increased rice production during that period was indebted 40 percent to the varietal improvement and 13 percent to the ameliorated agro-technologies, and the rest, 47 percent, could be ascribed to the other factors besides varieties and cultural technologies such as the improved agricultural environments, etc. Of course, even though it cannot be expected to unify the cultural environments and the cultural technologies, provided that much efforts are to be endeavored to minimize the yield difference of 20 percent between farmer and research organizations and the inter-regional yield difference of 20 percent, much increased rice production can be expected to be achieved with the current level of cultural technology and the yielding potential of the present rice varieties. In order to expedite the above effects on rice production the followings are to be put into practices consitently and steadfastly. 1. Reinforcement of breeding for varieties with high yielding potential and less susceptible to climatic-stress and pests, and of basic physicoecological studies of rice plant for improving the cultural technologies. 2. Continuous endeavor to secure the stabilized cultural environments by improving the soil fertility and increasing the drainage and irrigation facilities. 3. Political back-up to encourage the farmers' incentives for production 4. Precise surveys for agricultural statistics to facilitate the long-term planninge long-term planning.

• Korean Journal of Plant Resources
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• v.28 no.2
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• pp.263-270
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• 2015

To reduce the injury by continuous cropping system of tomato cultivation, green manure crops (GMCs) such as hairy vetch and rye were applied, Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in hairy vetch were 26.2, 5.8, 10.2, 6.6, and 1.5 ㎏/10a, respectively. Nutrient contributions of N, P₂O₅, K₂O, CaO, and MgO in rye were 9.1, 4.2, 11.8, 3.8, and 3.1 ㎏/10a, respectively. After incorporation of GMCs into soil, bulk density in soil with GMCs was lower than that in soil without GMCs (control). In soil after incorporation of GMCs, pH was not different in all treatment conditions, and ranged from 6.37~6.52. EC in soil after incorporation of GMCs was lower than that in soil without GMCs. The OM, T-N, and avail. P₂O₅ contents in soil with GMCs were higher than those in soil without GMCs. The tomato growths were increased in the rotational cropping system (RCS) as compared to continuous cropping system (control and without NPK). Also the density of Pseudomonas corrugata in soil with GMCs was lower than that in soil without GMCs (control). This study suggest that the RCS using GMCs showed lower disease outbreak density in soil for tomato cultivation as compared to RCS without GMCs. Especially, the GMCs was good effect for reduction of continuous cropping injury of tomato.

• Journal of Integrative Natural Science
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• v.14 no.1
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• pp.11-20
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• 2021

On November 17, 2019, an infectious disease with symptoms of pneumonia, called the Wuhan virus at the time, occurred in Wuhan, China. Since then, the name has been changed to COVID-19, and the virus has spread all over the world, and the WHO has declared the highest warning level for infectious diseases, "Pandemic". The coronavirus has also caused great confusion in South Korea. This resulted in large infected people.The first confirmed cases occurred on January 20, 2020, and the number of infected patients is steadily increasing after experiencing several waves, and many corona confirmed cases are also occurring in 2021 after the year. As the whole world enters a pandemic, walls are created between people and people, companies and businesses, and countries and countries, and all growth stops or declines, including human relationships, domestic companies and industries, and foreign industries. As a result, society in general is experiencing a lot of stagnation. Among them, small and medium-sized enterprises (SMEs), which are the basis of all growth in Korea, and youth who are trying to contribute to the national development by entering society, are struggling to find jobs. Even before the coronavirus outbreak, the difficulty of job hunting and the prospect of small and medium-sized businesses were not very good. In this situation, as the country's overall economic situation is poor, the vitality of SMEs has decreased a lot, the prospects are not good, so jobs are reduced, and there are many difficulties due to reluctance to hire new employees. In this study, with 2019 before the corona era and 2020 after the corona era, we compare SMEs before and after the corona era and overall job search and job search activities through average difference analysis, and whether they are affecting through correlation analysis. Through this, it suggests a direction to increase job search through corporate and government policies after raising the prospects of SMEs first.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.486-496
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• 2018

Pine wilt disease (PWD) in Gyeonggi province was first detected in Gwangju in 2007, and ever since has caused extensive damage. Insect vector and host tree in Gyeonggi province are Monochamus saltuarius and Pinus koraiensis, respectively, which are different from the southern region that consist of Monochamus alternatus and Pinus densiflora. Consequently, spread and mortality characteristics may be different, but our understanding is limited. In this research, we utilized the spatial data of newly infected trees in Gyeonggi province from 2008 to 2015 to analyze how it is related to various environmental and human factors, such as elevation, forest type, and road network. We also analyzed the minimum distance from newly infected tree to last year's closest infected tree to examine the dispersal characteristics based on new outbreak locations. Annual number of newly infected trees rapidly increased from 2008 to 2013, which then stabilized. Number of administrative districts with infected trees was 5 in 2012, 11 in 2013, and 15 in 2014. Most of the infected trees was Pinus koraiensis, with its proportion close to 90% throughout the survey period. Mean distance to newly infected trees dramatically decreased over time, from 4,111 m from 2012 to 2013, to approximately 600 m from 2013 to 2014 and 2014 to 2015. Most new infections occurred in higher elevation over time. Distance to road from newly infected trees continuously increased, suggesting that natural diffusion dispersal is increasingly occurring compared to human-influenced dispersal over time.