• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.4
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• pp.280-292
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• 2017

Hail is not a frequently occurring weather event, and there are even fewer reports of hail damages to forest stands. Since the 2000s, an increase in hail incidence has been documented in Europe and the United States. In Korea, severe hails occurred in Jeollanam-do province on May 31 and in Gyeongsangbuk-do province on June 1, 2017. Hail size was ranged from 0.5 to 5.0 cm in diameter in Jeollanam-do, and from 1.5 to 3.0 cm in Gyeongsangbuk-do. This study was aimed to analyze the hail damages to forests by species and topography based on damage-categorized maps created by using drones and aerial photographs, and to analyze relationships of the damages with meteorological factors. The total damaged forest area was 1,163.1ha in Jeollanam-do, and 2,942.3ha in Gyeongsangbuk-do. Among the 'severe' damaged area 326.7ha, 91% was distributed in Jeollanam-do, and concentrated in the city of Hwasun which covers 57.2% of the total 'severe' damaged area. The most heavily damaged species was Korean red pine(Pinus densiflora S. & Z.) followed by P. rigida. Most broad-leaved trees species including oaks were recovered without any dead trees found. Liliodendron tulipifera was the most severely damaged in terms of the rate of 'severe' degree individuals which are needed to be checked whether they will die or be recovered. Cause of the death of pines was considered as the combination of physical damage caused by the hail and long-lasting drought with high air temperature that occurred before and after the hail event. No pathogens and insects were found which might have affected to tree deaths. We suggested a dieback mechanism of the pine trees damaged by hail and drought.

• Korean Security Journal
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• no.61
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• pp.255-283
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• 2019

This study conducted a survey of 315 facility security workers in Daejeon, South Chungcheong Province and Gyeonggi Province for about a week from August 7 to August 13, 2019 to identify the impact of work environment and job stress on job satisfaction, and finally collected 293 of the total 315 parts of the data, excluding non-response and inappropriate responses. The STATA 14.2 Statistical Package Program was used for analysis of the collected data, frequency analysis was performed to determine the distribution ratio of the subjects, and reliability analysis and correlation analysis were performed with respect to the established key variables. Next, t-test and one-way ANOVA were conducted to verify differences in work environment, task stress and task satisfaction factors according to demographic characteristics, and the results were as follows: There were differences in work environment, job stress and job satisfaction recognition depending on demographic characteristics. In detail, the factors for the work environment indicated significant differences in age, academic background, number of years of service, wages and types of service in the recognition of the work environment. Job stress factors indicated significant differences in age, education, wages and types of service in job stress recognition. In job satisfaction factors, age, academic background, number of years of service and wages (monthly benefits) showed significant differences in job satisfaction recognition. In addition, the results of multiple regression analyses to identify the working environment, job stress, and job satisfaction are as follows. The working environment has had a positive impact on job satisfaction, and the better the job environment, promotion and organizational characteristics, the higher the job satisfaction. It has been shown that job stress has had a negative impact on job satisfaction, conflict of relationship (promoting colleagues). job autonomy increases job satisfaction, and job satisfaction decreases when job requirements and job insecurity increase. In terms of the impact of work environment on job satisfaction, the higher the work promotion, job environment and organizational characteristics, the higher the job satisfaction level, the report showed. According to these studies, the better the working environment, the lower the job stress, and the lower the job stress, the higher the job satisfaction. In addition, the better the working environment, the more satisfied the job was found to be, and the empirical research result was verified that improvement of the working environment of security workers can reduce job stress and improve job satisfaction through improvement of the working environment.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.35-44
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• 2006

Acceleration and deceleration curves have been used for design purposes worldwide. The curve in design level has been regarded as an single deterministic curve to be used for design of climb lanes. It should be noted that the curve was originally made using ideal driving truck and that the curve is applied during design based on the assumption of no difference between ideal and real driving conditions. However. observations show that aged vehicles and lazy behavioring drivers nay make lower performance of vehicles than the ideal performance. The present paper provides the results of truck speeds at climbing lanes then probabilistic variation of acceleration and deceleration corves. For these purposes. a study about identification of vehicle makers, and weights for trucks at freeway toll gates and then observation of vehicle-following speed were performed. The 85%ile results obtained were compared with the deterministic performance curves of 180, 200, and 220 Ib/hp. It was identified that the performance of 85%ile results obtained from vehicle-following-speed observations were lower than one from deterministic performance curves. From these results, it may be concluded that at the beginning Point of climbing lanes additional $16.19{\sim}67.94m$ is necessary and that at the end point of climbing lanes $53.12{\sim}103.24m$ of extension is necessary.

• Radiation Oncology Journal
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• v.20 no.3
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• pp.193-198
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• 2002

Purpose : Oligodendrogliomas (ODG) are a rare, slow growing, tumor in the brain, which can be cured by complete surgical resection, but as yet it is not known if postoperative adjuvant radiation therapy (RT) is essential, We analyzed the treatment results of patients with irradiated ODG to investigate the efficacy of RT in terms of survival rates and other influencing prognostic factors. Methods and Materials : Between March 1983 and December 1997, 42 patients with ODG were treated with RT at our hospital. The RT was peformed dally at a dose of $1.8\~2.0\;Gy$, at 5 fractions per week, to a total dose of between 39.6 Gy and 64.8 Gy (mean 53.3 Gy). The ages of the patients ranged between 5 and 62 years, with a median age of 39 years. The mean follow-up period was 63.4 months (8-152 months). The Kaplan-Meier method was used to assess the survival, and 5 year survival rates (5-YSR). Log rank tests and Cox regression analyses were used to define the significance of prognostic factors. Results : The majority of ODG in this study were located in the cerebral hemisphere $(83.3\%)$. ODG are slightly more common in men than women, and commonly occurs in middle age, between the 3rd and 4th decades. It has been recommended that RT is commenced within 4 weeks following surgery (5-YSR; $86\%\;vs.\;49\%;\;p<0.03$). Histologically well differentiated, as opposed to poorly differentiated, tumors were found to have a more favorable prognosis (p<0.02). The actuarial 5-YSR was $65.3\%$ (median survival 90 months). 5-YSR for the various extents of surgical excision, followed by external RT, was superior to that of biopsy only followed by external RT $(69.9\%\;vs.\;25.6\%,\;p<0.01)$. Tumor size and location, overall elapsed irradiation days, age, sex, whole brain irradiation as a course of treatment and chemotherapy, had no influence on the 5-YSR (p>0.05). Conclusion : A local involved field irradiation with conventional fractionation, commencing within 4 weeks following surgical excision of the tumor, was beneficial for the 5-YSR, but a total radiation dose exceeding 60 Gy did not improve the 5-YSR.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.517-529
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• 1998

Purpose : Although many studies have investigated the dosimetric aspects of stereotactic radiosurgery in terms of target volume, the absorbed doses at extracranial sites: especially the lens or thyroid - which are sensitive to radiation for deterministic or stochastic effect -have infrequently been reported. The aim of this study is to evaluate what effects the parameters of radiosurgery have on the absorbed doses of the lens and thyroid in patients treated by stereotactic radiosurgery, using a systematic plan in a humanoid phantom. Materials and Methods : Six isocenters were selected and radiosurgery was planned using the stereotactic radiosurgery system which the Department of Therapeutic Radiology at Seoul National University College of Medicine developed. The experimental radiosurgery plan consisted of 6 arc planes per one isocenter, 100 degrees for each arc range and an accessory collimator diameter size of 2 cm. After 250 cGy of irradiation from each arc, the doses absorbed at the lens and thyroid were measured by thermoluminescence dosimetry. Results : The lens dose was 0.23$\pm$0.08$\%$ of the maximum dose for each isocenter when the exit beam did not pass through the lens and was 0.76$\pm$0.12$\%$ of the maximum dose for each isocenter when the exit beam passed through the lens. The thyroid dose was 0.18$\pm$0.05$\%$ of the maximum dose for each isocenter when the exit beam did not pass through the thyroid and was 0.41$\pm$0.04$\%$ of the maximum dose for each isocenter when the exit beam Passed through the thyroid. The passing of the exit beam is the most significant factor of organ dose and the absorbed dose by an arc crossing organ decides 80$\%$ of the total dose. The absorbed doses of the lens and thyroid were larger as the isocenter sites and arc planes were closer to each organ. There were no differences in the doses at the surface and 5 mm depth from the surface in the eyelid and thyroid areas. Conclusion : As the isocenter and arc plane were placed closer to the lens and thyroid, the doses increased. Whether the exit beams passed through the lens or thyroid greatly influenced the lens and thyroid dose. The surface dose of the lens and thyroid consistently represent the tissue dose. Even when the exit beam passes through the lens and thyroid, the doses are less than 1$\%$ of the maximum dose and therefore, are too low to evoke late complications, but nevertheless, we should try to minimize the thyroid dose in children, whenever possible.

• Radiation Oncology Journal
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• v.19 no.3
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• pp.205-210
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• 2001

Purpose : This study tried to evaluate the effectiveness of combined treatment using radiation therapy and concurrent cisplatin as a radiosensitizer in the management of locally advanced head and neck cancer. Materials and methods : From January 1995 to August 1998, 29 evaluable patients with locally advanced head & neck cancels (AJCC stage $II\~IV$) were received curative radiation therapy $(total\;70\~75.6\;Gy/35\~42\;fractions,\;1.8\~2\;Gy/fraction)$ and concurrent cisplatin chemotherapy ($100\;mg/m^2$, D1, D22, D43). The neck dissections were peformed for residual lymphadenopathy. Follow-up ranged from 5 to 55 months (median 24 months). Results : Twenty-one $(72.4\%)$ patients achieved clinical complete responses. The partial response and minimal response rates were $17.2\%\;and\;10.4\%$, respectively. Locoregional failure rate was $27.6\%$, and included 6 patients with local failures, 4 patients with regional failures, and 2 patients with combined local and regional failures. Four of 29 patients $(13.8\%)$ developed distant metastasis. The disease free survival rate at 3 years was $60\%$. Nasopharyngeal primary tumors or complete responders showed significantly higher disease free survival rate. The grade 3 mucositis and nausea/vomiting was noted in $34.5\%$, respectively. Major prolongation of radiation therapy duration was inevitable in three patients. Twenty-one patients $(72.4\%)$ completed 3 courses of cisplatin and 5 patients received 2 courses of cisplatin. Three patients received only one course of cisplatin due to nephrotoxicity and neurotoxicity, and then changed to 5-FU regimen. Conclusions : Concurrent cisplatin-radiation therapy in locally advanced head and neck cancer showed high response rate, reasonable locoregional control, and survival rate. As expected, acute toxicities were increased, but compliance to treatment was acceptable. Assessment of the effect of the combination in this setting requires further accrual and follow-up.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.441-446
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• 1998

Purpose : The incidence of esophageal carcinoma is increasing. Radical surgery is the treatment of choice, but large proportion of the esophageal cancer patients are with unresectable disease at the time of initial diagnosis, so radiation therapy has been the major treatment modality. We carried out retrospective analysis to see the outcome and prognostic factors of radiation therapy alone for esophageal carcinoma. Methods and Materials : From June of 1979 through December 1992, 289 patients with esophageal carcinoma were treated with radiation therapy alone at Department of Therapeutic Radiology, Seoul National University Hospital. Of these patients, 84 patients were excluded as they were ineligible for the current analyses. Twenty-two patients had distant metastasis other than supraclavicular lymph node metastasis, 52 patients received less than 45 Gy, and 10 patient were lost from follow-up. Therefore 205 patients constituted the base population of this study. According to AJCC s1aging system, there were 2 patients with stage 1, 104 with stage IIA, 26 with stage IIB, 48 with stage III, and 25 with stage IV Radiation dose ranged from 4500 cGy to 6980 cGy with median dose of 5940 cGy. Follow-up period of the alive patients ranged from 77 to 180 months. Results : The Median survival period of all the patients was II months and the 2-, 5-, and 10-year overall survival rates were 22.4$\%$, 10.2$\%$ and 5.3$\%$, respectively. Most of the failures were local recurrences. Of 169 failures, 134 had local failure as a component and 111 had local recurrence only. The Lymph node was most common distant metastatic site and the next was the lung. The stage, T-stage, N-stage, functional status, tumor size, and aim of treatment were statistically significant prognostic factors for survival by univariate analyses. But only tumor size and N-stage were significant by multivariate analyses. Conclusion : We could get 10.2$\%$ of 5 year survival rate and 5.3$\%$ of 10 year survival rate with radiation therapy alone. The size of tumor and N-stage were statistically significant prognostic factors for survival on multivariate analyses.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.41-50
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• 1983

The incidence of sexually transmitted disease, especially gonorrhoea has risen despite the progress in its diagnosis and treatment. For the effective control programs of sexually transmitted disease, it should be required socio-medical approaches. A study on gonorrhoea and penicillinase-producing Neisseria gonorrhoeae(PPNG) was conducted in Jeonju and Kunsan area from March, 1982 through August, 1982. The 221 entertrainers were studied in order to determine the prevalences of gonorhoea and PPNG. Socio-demographic informations of the entertainers were obtained by interviewing them. Gonococci were cultured on Thayer-Martin enrichment media for isolation, and PPNG was confirmed using beta-lactamase reagent ($PADAC^{tm}$ Beta-Lactamase Test Strips, Galbiochem-Behring). The results of the study are summarized as follows; 1. The average age of the entertainers studied was $26.1{\pm}4.7$ years. 2. The average years of working in entertaining business was $2.4{\pm}1.4$ years, and the average income per month was $239,592{\pm}90,480$ won. On the education level, 70.6% of the entertainers were middle or high school graduates 3. 47.5% of the entertainers were using contraceptives. 90.5% have experienced artificial abortion. 4. 37(16.7%) out of 221 entertainers were revealed to gonorrhoea, and 13 (35.1%) of gonorrhoea patients were by PPNG. 5. The prevalence rates of gonorrhoea and the proportion of PPNG by age were not significant statistically. Meanwhile, the colelations between the rates of gonorrhoea and education, frequency of love-making with customers and type of sexual partner were highly significant statistically. 6. 37 strains of gonococci isolated were almostly resistant to several antimicrobial agents, especially amikacin, clindamycin and chloramphenicol. Furthermore PPNG strains were completely resistant to not only above drugs but also penicillin.

• Journal of Preventive Medicine and Public Health
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• v.22 no.4 s.28
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• pp.578-590
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• 1989

This study was conducted to assess the equity in the regional insurance scheme through analysis of the computerized data from one regional insurance society and National Federation of Medical Insurance. We analysed the insurance contribution and benefit by the classes based on total and income-related contribution per household. The major findings of this study are as follows : 1. The average proportion of income-related contribution among the total was 39.2% and the upper classes show higher proportion of the income-related contribution. 2. The upper classes show higher health care utilization rate than the lower classes. It suggests that the lower classes have relatively large unmet medical needs. 3. The analysis through the Lorenz curve reveals that there exists transference of contributions from the upper to lower classes. But the cumulative percentage of insurance benefit is smaller than that of the number of the insured. It implies that regional medical insurance scheme in Korea has still some inequity in the context of social security principles.

• Childhood Kidney Diseases
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• v.10 no.1
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• pp.18-26
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• 2006

Purpose : Empirical antimicrobial treatment is indicated before bacteriological results are available for young children with febrile UTI to minimize renal scarring. To ensure appropriate therapy, knowledge of the prevalence of causative organisms and their susceptibility patterns to antimicrobials is mandatory. We performed a retrospective analysis investigating the local prevalence and resistance patterns of uropathogens, primarily E. coli, isolated from community-acquired UTIs. Methods : A total of 103 positive urine cultures from children with febrile UTI collected at Bundang CHA General Hospital from February 2004 to February 2005 were analyzed. Inclusion criteria were fever higher than $37.5^{\circ}C$, significant bacteriuria with single strain growth of at least 10s colony forming units/mL urine, and leukocyturia >5/HPF. Results : E. coli(89.3%) was the leading uropathogen followed by Enterococcus spp.(3.9%) Klebsiella spp.(2.9%), Citrobctcter spp.(1.9%) and Enterobacter spp.(1.9%). E. coli strains revealed a low proportion of antimicrobial susceptibility to ampicillin(AMP; 27.2%) ampicillinsulbactam(AMS; 34.8%) and trimethoprim-sulfamethoxazole(SXT; 65.2%). Susceptibility patterns to cephalosporins were as follows; cefazolin(1st generation; 91.3%), cefoxitin(2nd; 100%), ceftriaxone(3rd; 97.8%) and cefepime(4th; 97.8%). Three E. coli isolates produced ex tended - spectrum beta-lactamase(ESBL). Conclusion : Empirical treatment with AMP, AMS and SXT, which are commonly used in pediatric clinics, is not recommended for childhood UTI due to high incidence of resistance. The high level of susceptibility to cephalosporins makes these drugs reasonable alternatives. However the emergence of ESBL-producers, even though they are quite few, may have an impact on cephalosporin treatment in the future. (J Korean Soc Pediatr Nephrol 2006;10:18-26)