• Journal of the Korean earth science society
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• v.36 no.7
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• pp.661-673
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• 2015

UBVI CCD photometry of the intermediate age open cluster NGC 7790 has been obtained using AZT-22 1.5 m telescope (f/7.74) at the Maidanak Astronomical Observatory in Uzbekistan. NGC 7790 contains three ${\delta}$ Cep variable stars including CEa Cas, CEb Cas, and CF Cas. PSF photometry was carried out using IRAF/DAOPHOT for all observations. The total number of stars observed both in V and I filter was 1008 and the limiting magnitude was $V{\approx}22$. To determine atmospheric extinction coefficients and photometric zero points, many blue and red standard stars as well as the standard stars in the celestial equator under various airmass were observed. Photometric data were transformed into the standard Johnson-Cousins' UBVI standard system. From the analysis of UBVI color-magnitude diagram and color-color diagram, the color excess in V and I filter [$E(B-V)=0.58{\pm}0.02$], the selective extinction ratio in V and I filter [$R_V{\equiv}A_V/E(B-V)=3.02{\pm}0.09$] and distance modulus ($V_0-M_V=12.65{\pm}0.10$) of the cluster were determined. The age of the cluster was estimated to be log $age=8.05{\pm}0.05$ [yr] based on the position of these three Cepheid variables in the color-magnitude diagram, the isochrone of the Geneva group ($Ekstr{\ddot{o}}m$ et al., 2012-Z=0.019), and the isochrone of the Padova group (Bressan et al., 2012-Z=0.014) were used to compare each other. Of them, the Geneva models that considered stellar rotation well described the position of ${\delta}$ Cepheid variables in the blue loop. Although they were well consistent with standard period-luminosity relation of ${\delta}$ Cepheid variables, three Cepheid variables in NGC 7790 were, on average, brighter by about 0.5 mag than the absolute magnitude estimated from the mean period-luminosity relation at a given period.

• Journal of radiological science and technology
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• v.37 no.2
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• pp.125-134
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• 2014

This study is to provide basic information regarding photoneutron doses in terms of radiation treatment techniques and the number of portals in intensity-modulated radiation therapy (IMRT) by measuring the photoneutron doses. Subjects of experiment were 10 patients who were diagnosed with prostate cancer and have received radiation treatment for 5 months from September 2013 to January 2014 in the department of radiation oncology in S hospital located in Seoul. Thus, radiation treatment plans were created for 3-Dimensional Conformal Radiotherapy (3D-CRT), Volumetric-Modulated Arc Radiotherapy (VMAT), IMRT 5, 7, and 9 portals. The average difference of photoneutron dose was compared through descriptive statistics and variance analysis, and analyzed influence factors through correlation analysis and regression analysis. In summarized results, 3D-CRT showed the lowest average photoneutron dose, while IMRT caused the highest dose with statistically significance (p <.01). The photoneutron dose by number of portals of IMRT was $4.37{\pm}1.08mSv$ in average and statistically showed very significant difference among the number of portals (p <.01). Number of portals and photoneutron dose are shown that the correlation coefficient is 0.570, highly statistically significant positive correlation (p <.01). As a result of the linear regression analysis of number of portals and photoneutron dose, it showed that photoneutron dose significantly increased by 0.373 times in average as the number of portals increased by 1 stage. In conclusion, this study can be expected to be used as a quantitative basic data to select an appropriate IMRT plans regarding photoneutron dose in radiation treatment for prostate cancer.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.16-24
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• 1998

To determine the optimum application of fertilizers for the cultivation of Chinese cabbage in plastic film house, twenty soils which contain different salts contents were taken from 4 different area of plastic film house cultivation, Youngdong. Boeun county, Cheongweon county, and Cheongju city. The dry weight and the amount of N. P, and K uptakes of Chinese cabbage in the plot of no fertilization were considered as the factors representing the fertility of the soil. And a difference of dry weight and the amounts of N, P, and K uptakes of plants between the plot of fertilization and no fertilization were considered as the factors representing the total effect of fertilizer and fertilizer N, P, and K effects. respectively. These factors of soil fertility and fertilizer effects were estimated by correlation and regression with soil tests in order to find the critical levels and recommended method for optimum fertilization of Chinese cabbage. Chinese cabbage transplanted in two soils, having the electrical conductivity of 9.3 and 15.2 dS/m, were not able to root due to the salts toxicity. The content of inorganic N, the electrical conductivity, and CEC were founded to have significant correlation with the factors of both the soil fertility and fertilizer effects for the cultivation of Chinese cabbage. To determine the weighting degree for the productivity and the fertilizer effects, the standardized partial regression coefficient was analyzed by regression among the factors of fertility, the fertilizer effects, and the soil tests. The coefficient for inorganic N($NH_4-N$ and $NO_3-N$) was obtained as the absolute value of 756-1871 and this value was extremely higher than those of other soil tests which was 0.07-4.11. These results suggested that the content of inorganic N is the best tests for the estimation of the productivity and the fertilizer effects for the cultivation of Chinese cabbage in plastic film house. The critical level of inorganic N($NH_4-N+NO_3-N$) estimated by Cate-Nelson split method for maximum productivity and zero point of fertilizer effect was 220 mg/kg for all the factors of estimation. These results suggested that no application of fertilizer N. P, and K is required at the critical level of inorganic N of soil. Consequently the optimum application of fertilizer N, P, and K for the cultivation of Chinese cabbage in plastic film house was possible to determine by the critical level of inorganic N of soil. The critical level of electrical conductivity was estimated as 2.8 dS/m by the same method.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.1
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• pp.63-71
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• 2020

Objectives : The aim of this study was to investigate the impact of clinical and psychological factors on the parental stress of children and adolescents with epilepsy. Methods : Children and adolescents with epilepsy (n=90, age range=6-17 years) completed questionnaires on epilepsy-related variables, children's depressive symptoms (Children's Depression Inventory, CDI), children's anxiety (Revised Children's Manifest Anxiety Scale, RCMAS) and performed the scale for children's intelligence (IQ). Parents who have children and adolescents with epilepsy completed questionnaires on parental stress (Questionnaire on Resources and stress, QRS), parental anxiety (State-Trait Anxiety Inventory, STAI), children's attention problems (Abbreviated Conners Parent Rating Scale Revised, CPRS), and children's behavioral problems (Korean Child Behavior Checklist, K-CBCL). Stepwise regression analysis was performed to determine the significant predictive variables that affect parental stress. Results : In the correlational analysis, duration of seizure treatment (r=0.253, p=0.016), children's IQ (r=-0.544, p<0.001), children's attention problems (r=0.602, p<0.001), children's depressive symptoms (r=0.335, p=0.002), children's anxiety (r=0.306, p=0.004), children's behavioral problems (r=0.618, p<0.001), and parental anxiety (r=0.478, p<0.001), showed a significant correlation with parental stress. Children's behavioral problem (β=0.241, p=0.010), children's IQ (β=-0.472, p<0.001), and parental anxiety (β=0.426, p<0.001) were significantly related to the parental stress (Adjusted R²=0.619). Conclusions : Clinicians should pay attention to children's intelligence and behavioral problems and parental anxiety, which affect parental stress with children and adolescents with epilepsy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.6
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• pp.1309-1320
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• 2015

This study made an attempt to analyse the relationship between operation environment and fleet size per route which represents the level of service for inner-city bus service. Regression analysis method has been adopted as main analysis tool and 98 routes of bus operation status in Ulsan city as of 2013 has also been selected for analysis target. Correlation analysis was performed to identify the relationship between dependent and independent variables. There are three types of model for whole sample, type operation, and bus route operation system. These are the results of the current study. 1. The model developed for whole sample of 98 routes is as follows. Y(Fleet Size)=$-4.532+0.00002877*X_1$(Revenue). This model shows that it is necessary to have more than 140 passengers per day to increase fleet size of each bus route in Ulsan. 2. Models developed by type of operation (which are standard, express, and middle sized) are shown below. Stand Bus : Y(Fleet Size)=$-10.954+0.00004283*X_1$(Revenue). It is identified that more than 153 passengers need to use standard bus to increase fleet size per each standard bus, Middle Sized Bus : Y(Fleet Size)=-0.859+0.00001438*X1(Revenue). For middle sized bus, at least 52 daily passengers are needed to increase number of bus in each route. 3. Models developed for each route operation systems are as belows. Joint Operation Group : Y(Fleet Size)=$-4.786+0.00003028*X_1$(Revenue). Individual Operation Group : Y(Fleet Size)=$-2.339+0.00002030*X_1$(Revenue). These model provide similar result which 140 people is the minimum number of passenger to raise the number of vehicles in each route. This result shows that the route operation systems does not affect the raise number of cars significantly.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.398-410
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• 1982

Summer crops grown in uplands are greatly diversified and show a large variation in difference with year and location in Korea. The principal factor for the variation is weather, in which precipitation and temperature play a leading role and such a weather factors as wind, sun lights also influence production of the summer crops. Since artificial control of weather conditions as a main stress factor for crop production is almost impossible, it must be minimized only by an improvement of cultivation techniques and crop improvement. Precipitation plays a role as one of the most important factor for production of the summer crops and it is considered in two aspects, drought and excess moisture. This country, which belongs to monsoon territory, necessarily encounter one of this stress almost every year, even though the level is different. Therefore, the facilities for both drought and excess moisture are required, but actually it is not easy to complete for them. On this account, crops tolerant to drought, excess moisture and pests should be considered for establishing summer crops. For the districts damaged habitually every season, adequate crops should be cultured and appropriate method of planting, drainage and weed control should be applied diversely. Injuries by temperature is mainly attributed to lower temperature particularly in late fall and early spring, although higher temperature often causes some damages depending upon the kind of crops. Sometimes, lower temperature in summer season playa critical role for yield reduction in the summer crops. However, certain crops are prevented to some extent from this kind of stress by improving varieties tolerant to cold, hot weather or early maturing varieties. As is often the case, control of planting time or harvesting is able to be a good management for escaping the stress. Lodging, plant diseases and pests are considered as a direct or indirect damage due to weather stress, but these are characters able to be overcome by means of crop improvement and also controlled by other suitable methods. In addition, polytical supports capable of improving constitution of agriculture into modern industry is urgently required by programming of data for the damages, establishment of damage forecasting and compensation system.

• Journal of Korea Port Economic Association
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• v.37 no.2
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• pp.73-89
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• 2021

The handysize bulk carriers are capable of transporting a variety of cargo that cannot be transported by mid-large size ship, and the spot chartering market is active, and it is a market that is independent of mid-large size market, and is more risky due to market conditions and charterage variability. In this study, Granger causality test, the Impulse Response Function(IRF) and Forecast Error Variance Decomposition(FEVD) were performed using monthly time series data. As a result of Granger causality test, coal price for coke making, Japan steel plate commodity price, hot rolled steel sheet price, fleet volume and bunker price have causality to Baltic Handysize Index(BHSI) and charterage. After confirming the appropriate lag and stability of the Vector Autoregressive model(VAR), IRF and FEVD were analyzed. As a result of IRF, the three variables of coal price for coke making, hot rolled steel sheet price and bunker price were found to have significant at both upper and lower limit of the confidence interval. Among them, the impulse of hot rolled steel sheet price was found to have the most significant effect. As a result of FEVD, the explanatory power that affects BHSI and charterage is the same in the order of hot rolled steel sheet price, coal price for coke making, bunker price, Japan steel plate price, and fleet volume. It was found that it gradually increased, affecting BHSI by 30% and charterage by 26%. In order to differentiate from previous studies and to find out the effect of short term lag, analysis was performed using monthly price data of major cargoes for Handysize bulk carriers, and meaningful results were derived that can predict monthly market conditions. This study can be helpful in predicting the short term market conditions for shipping companies that operate Handysize bulk carriers and concerned parties in the handysize chartering market.

• Korean Journal of Environment and Ecology
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• v.30 no.1
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• pp.118-129
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• 2016

The purpose of this study was to offer the preliminary data for the development of forest therapy program. This exploratory study is about the development of forest healing program by identifying what is the forest healing program preferences of potential consumers and would be an important basis for the operation. The survey of interests and needs of 620 people on the forest therapy was analyzed. Using SPSS 21.0 program, statistical analysis, frequency analysis, T-test, One-way ANOVA, we looked at the differences in forest healing program preferences according to gender, age, occupation. Forest therapy program preference was found to vary depending on sex, age and job. First, according to gender, men preferred athletic in the forest and camping compared to women, and women showed a higher preference than men in the overall program. Second, depending on age, as compared to other age, for 20s; stress assessment & diagnosis, cooking in the forest, photo therapy in the forest, for 30s; walking in the forest, counseling, listening to lectures(stress-related or interpersonal relationships-related), communication-related lectures and vision quest, for 40s; meditation, viewing the forest, forest bathing wind bathing sun bathing, walking on barefoot in the forest, for 50s; breathing breathing exercises, yoga, mountaineering, climbing in silence, eating wild food, respectively, each of those programs were especially favored. Third, the forest healing program preference in accordance with the job is as follows. For students; stress assessment & diagnosis, cooking in the forest, etc., for teachers; walking in the forest, mountaineering, reading in the forest, viewing the forest, forest bathing wind bathing sun bathing, camping etc., for housewives; yoga, listening to the sound of water flowing, drinking herbal tea, eating wild food, for specialist researcher; breathing breathing exercises, climbing in silence, meditation, sleeping in the forest, respectively, each of those programs were especially favored. We expect the results of this study to be utilized as basic data for the development of forest therapy program targeting on adults.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.87-92
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• 2010

Purpose: In 2003, we decided to buy a PET/CT, at the time, it was the latest cancer diagnostic medical equipment. Equipment company was offered the marketing of collaboration operation because the highly cost of PET/CT. However, this hospital's choice was own purchase way. In this study we evaluated the collaboration operation way by post-mortem analysis to the current situation. Materials and Methods: From 2004 until 2008, five years, we investigate the revenue analysis the number of PET/CT cases about own purchase way and collaboration operation way according (ABC costing). Results: The year 2004, own purchase way is 4 billion 9 thousand 2 hundred million won in deficit, the collaboration operation way is 1 billion 1 thousand 7 hundred million won in deficit. The year 2005, own purchase way is 1 billion 5 hundred million won in deficit, collaboration operation way is 8 thousand 7 hundred million won in deficit. However, the year 2006, own purchase way is 5 billion 1thousand 3 hundred million won in surplus, collaboration operation way is 9 thousand 9 hundred million won in deficits. The year 2007 and 2008, revenue of own purchase way is more increased but the collaboration operation way is more decreased. From the year 2004 to 2008, subtotal of own purchase way is 10 billion 8 thousand 8 hundred won in surplus, sub-total of collaboration operation way is 6 billion 7 thousand million won in deficit. Conclusion: Own purchase way has been a big benefit occurs and to reflect the equipment price, the collaboration operation way became to deficit continues. In other words, the problem of collaboration operation way showed us. When you buy the high cost Equipment, consideration will be risk and economic analysis of variance, the appropriate of the initial investment cost, clinical diagnostic needs and etc.

• Journal of Yeungnam Medical Science
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• v.6 no.2
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• pp.173-181
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• 1989

The effect of interpregnancy interval on birthweight of the subsequent child was investigated for the 1,347 womens of 25 to 40 years old age who visited OBGY and Pediatric department of the general hospital in Taegu city. Questions in designed questionnaire were asked by student interviewers who were trained in nursing school. Mean birth weight by interpregnancy intervals were compared by the intervals of 6 months. Mean birth weight increased from 3,250 grams for intervals of 6 months to 3,357 grams for intervals of 25-30 months, hut the difference was not statistically significant(=0.47). Correlations between the continuous variables which were suspected as con founders and interpregnancy interval and birth weight were investigated. The coefficient of correlation between maternal age and interpregnancy interval was 0.39, between gestational period and birth weight 0.30 and between prepregnant weight and birth weight 0.16 and between birth weight of first baby and birth weight(of second baby) 0.44. But maternal age, gestational period and prepregnant weight were not considered as confounder, because they were not correlated simultaneously with birth interval and birth weight. Associations between the discrete variables which were suspected as confounders, and interpregnancy interval were investigated by Chi-square test. Associations between interpregnancy interval and educational level of mothers, types of husband's occupation, types of medical security, sex were not significant(P-values were 0.59, 0.75, 0.75, 0.82 respectively), so we did not considered these variables as confounding variables. In multiple regression analysis of birth weight, significant variables were birth weight of first baby, gestational period, sex of neonate and prepregnancy body weight of mother. Of the 1,347 births, the rate of low birth weight was 2% (27 birth). The rate for interpregnancy interval 7-12 months was highest as 3.6% and that for 13-18 months was lowest as 0.6%, but there was no regular tendency related with interpregnancy interval.