• Journal of radiological science and technology
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• v.37 no.3
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• pp.177-185
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• 2014

This study focused on effects of patient exposure dose reduction with AEC (Auto Exposure Control) marker that is designed for showing location of AEC in X-ray Chest radiography. It included 880 adults who have to use Chest X-ray Digital Radiography system (DRS, LISTEM, Korea). AEC (Ion chambers are posited in top of both sides) are used to every adult and set X-ray system as Field size $17{\times}17inch$, 120kVp, FFD 180cm. 440 people of control group are posited on detector to include both sides of lung field and the other 440 people of experimental group are set to contact their lung directly to Ion chamber (making marker to shows location). Then, measured every DAP and, estimated patient effective dose by using PCXMC 2.0. The average age of control group (M:F=245:195) is 53.9 and the average BMI is 23.4. BMI ranges from under weight: 35, normal range: 279, over weight: 106 to obese: 20 and average DAP is 223.56mGycm2, Mean effective dose is 0.045mSv. The average age of experimental group (M:F=197:243) is 53.7 and the average BMI is 22.7. BMI ranges from under weight: 34, normal range: 315, over weight: 85 to obese: 6 and average DAP is 207.36mGycm2, Mean effective dose is 0.041mSv. Experimental group shows less Mean effective dose as 0.004mSv (9.7%) than control group. Also, patient numbers who got over exposure more than 0.056mSv (limit point to know efficiency of AEC marker) is 65 in control group (14.7%), 19 in experimental group (4.3%) and take statistics with t-Test. The statistical difference between two groups is 0.006. In order to use proper amount of X-ray in auto exposure controlled chest X-ray system, matching location between ion chamber and body part is needed, and using AEC marker (designed for showing location of ion chamber) is a way to reduce unnecessary patient exposure dose.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.245-251
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• 1994

The initial growth and herbicidal responses of Scirpus planiculmis were examined under both laboratory and greenhouse condition. Initial growth of S. planiculmis at two different soils(soil A and B), was compared with the growth at normal paddy soil, and growth rates at two soils were 32% and 86% as compared to the growth rates at normal paddy soil. Two different soils were soil A(rice-uncultivable) and soil B(rice-cultivable). Transplanted(2.5 leaf stage) and direct seeded rice(Dongjinbyeo) could not grow at soil A. The growth of transplanted rice at soil B was almost same as the growth at normal paddy soil, but the growth of direct seeded rice was 50% of the growth at normal paddy soil. S. planiculmis among the perennial weeds was most tolerant to NaCl, and Cyperus serotinus, Eleocharis kuroguwai, Sagittaria pygmaea, Sagittaria trifolia, Potamogeton distinctus were followed. The intial growth rate of S. planiculmis was more rapid than C. serotinus. Cutting types and times of corm reduced 20-40% of the initial growth of S. planiculmis. During the initial growth of S. planiculmis, the growth of S. planiculmis was severly inhibited by the earlier removal of corm from seedlings, and it represents that the corm plays an important role in the initial growth of this species. Bentazone among 14 commercialized herbicides showed the best safety on direct seeded rice and the highest control effect agaist S. planiculmis.

• Radiation Oncology Journal
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• v.26 no.3
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• pp.181-188
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• 2008

Purpose: In order to enhance the efficiency of respiratory gated 4-dimensional radiation therapy for more regular and stable respiratory period and amplitude, a respiration training system was designed, and its efficacy was evaluated. Materials and Methods: The experiment was designed to measure the difference in respiration regularity following the use of a training system. A total of 11 subjects (9 volunteers and 2 patients) were included in the experiments. Three different breathing signals, including free breathing (free-breathing), guided breathing that followed training software (guided-breathing), and free breathing after the guided-breathing (post guided-breathing), were consecutively recorded in each subject. The peak-to-peak (PTP) period of the breathing signal, standard deviation (SD), peak-amplitude and its SD, area of the one cycle of the breathing wave form, and its root mean square (RMS) were measured and computed. Results: The temporal regularity was significantly improved in guided-breathing since the SD of breathing period reduced (free-breathing 0.568 vs guided-breathing 0.344, p=0.0013). The SD of the breathing period representing the post guided-breathing was also reduced, but the difference was not statistically significant (free-breathing 0.568 vs. guided-breathing 0.512, p=ns). Also the SD of measured amplitude was reduced in guided-breathing (free-breathing 1.317 vs. guided-breathing 1.068, p=0.187), although not significant. This indicated that the tidal volume for each breath was kept more even in guided-breathing compared to free-breathing. There was no change in breathing pattern between free-breathing and guided-breathing. The average area of breathing wave form and its RMS in postguided-breathing, however, was reduced by 7% and 5.9%, respectively. Conclusion: The guided-breathing was more stable and regular than the other forms of breathing data. Therefore, the developed respiratory training system was effective in improving the temporal regularity and maintaining a more even tidal volume.

• Korean Journal of Plant Resources
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• v.31 no.1
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• pp.77-85
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• 2018

The cultivation area of rapeseed (Brassica napus L.) has been increased for oil production and landscaping purpose in Korea. However, as the color of rapeseed flower is very simple, diversified flower color is necessary to improve landscape effect. Interspecific and intergeneric crosses between rapeseed (Brassica napus) and three Cruciferae crops were performed in order to grow diverse flower color of rapeseed. The silique formation rate of interspecific cross rapeseed with cabbage (B. oleracea L) was relatively high (65.8%) and higher than intergeneric cross with rapeseed and radish (Raphanus sativus L.), rapeseed and Orychophragmus, respectively. During silique developing period after artificial pollination, there were many siliques without seeds due to the failure of fertilization. The average number of seed per silique obtained from cross rapeseed and cabbage, rapeseed and radish, rapeseed and O. violaceus were 0.12, 0.4 and 0.12, respectively. The phenotypes of $F_1$ hybrid plants from cross rapeseed and Cruciferae crops were mostly similar to maternal line, but leaf length and leaf width were increased. The interspecific cross of rapeseed and cabbage generated ivory color of flower which is the medium color of parents, and intergeneric cross of rapeseed and O. violaceus created entities with larger flowers which seems to enhance landscape effect. The fatty acid composition of most hybrid seeds intermediated of the two parents for oleic acid, linoleic acid and linolenic acid, content. Whereas hybrid of rapeseed and radish produced less erucic acid than radish parent.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.411-418
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• 2014

This study, in order to establish the effect of three exercise groups on the static and dynamic balancing abilities and the muscular activity, targeting adult males aged 20-29, assigned 15 men to each aquatic exercise group, trunk stabilization exercise group, and balance exercise group. The study was conducted from June, 2013 to August, 2013, and measured and compared the balancing ability and the muscle activity(tibialis anterior and gastrocnemius muscle) of the participants after performing intervention for 30 minutes a day, 3 days a week, for 6 weeks. As a result, on the comparison between before and after the intervention, there were significant differences in changes of the surface area and the whole path length in all the three groups(p<.05)(p<.01), and also on the dynamic balance, there was a significant difference in change of limited of stability(p<.05)(p<.01). On change of the muscle activity of tibialis anterior, both left and right sides showed statistically significant differences in all the three groups(p<.05)(p<.01), and gastrocnemius muscle showed a statistically significant difference in all the three groups except for the left side of the trunk stabilization exercise group(p<.05)(p<.01). It could be established that aquatic exercise is effective for improvement of the balancing ability and increase of the muscular activity, and we intend to propose specific aquatic exercise program development by conducting a study to determine the objective effect of aquatic exercise on the elderly or patients who have a poor balancing ability.

• Korean Journal of Environment and Ecology
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• v.34 no.4
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• pp.294-303
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• 2020

This study aimed to examine was conducted to the ability of microclimate control in old pine forests by surveying pine forest in Buddhist temples, where the pine forest are stably growing through active protection in the Gyeongnam region, and comparing variation characteristics of microclimate characteristics (temperature and humidity) and distribution of vegetation type. The study sites were pine forests protected well by Buddhist temples (Haein-sa, Beomeo-sa, Tongdo-sa, and Bulguk-sa) in the southeast region of Korea and thus known for stably growing young pine trees. According to the vegetation distribution status analysis, these pine forests did not have a high ratio of pine trees. Except for Tongdo-sa, the ratio of deciduous forest and mixed (deciduous and pine trees) forest had a much larger presence than that of pine forest. Measured data of microclimate showed that the Tongdo-sa area had significantly different characteristics compared to the other three areas. Tongdo-sa area showed a significantly higher diurnal range of temperatures and humidity than the other three areas, in both spring and summer. It is due to the difference in vegetation management. The forests around Tongdo-sa are mostly pine forests, except for the developed areas, while those in the other three areas have a dominant ratio of deciduous brad-leaved forests. Intensive control of pine forest is not effective in mitigating microclimate, i.e., temperature and air humidity. Stress caused by rising temperatures and decreasing air humidity is blamed for the decline of pine forests. Thus, the current active management of pine forests, such as the Tongdo-sa case, has been found to have a greater negative impact on the temperature and humidity stress. Therefore, we believe that a new change in forest management is necessary to increase the effect of mitigating the microclimate of pine forests.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.4
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• pp.1-10
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• 2017

This study investigated indoor temperature and humidity control and PM1 and PM10 mitigation effects of a single green wall (Case 1), two green walls (Case 2), and two green walls plus a waterfall (Case 3) in comparison with a control without either a green wall or waterfall. Experiments were conducted in the office of Chungbuk National University from August to September, 2015. Experiments were carried out sequentially in the order of control, Case 1, Case 2, and Case 3. Data collected from August 17 to August 20, 2015 (Experiment 1), and from August 31 to September 3, 2015 (Experiment 2), when outdoor temperature was relatively constant, were analyzed. Plant volume ratios by indoor landscaping of the control, Case 1, Case 2 and Case 3 were 0.0, 0.6, 1.2, and 1.4%, respectively. Compared to the control, average temperatures of Case 1, Case 2 and Case 3 were decreased by 0.3~0.7, 0.7~0.9 and $1.0^{\circ}C$, respectively, and relative humidity was increased by 1.8~8.7, 9.2~14.6 and 14.8~21.9%, respectively. Three hundred minutes after exposure to mosquito repellent incense particles, the ratio of the remaining PM1 of the control, Case 1, Case 2 and Case 3 were 25.0, 22.0%, 21.2%, 17.3%, respectively, in Experiment 1 and 42.3, 28.9, 23.1, and 30.9%, respectively, in Experiment 2. As indoor greening increased the effect of indoor temperature, PM1 and PM10 mitigation were greater, and temperature and humidity were lower. The greater the relative humidity was, the faster PM1 and PM10 mitigation tended to be.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.2
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• pp.52-61
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• 2018

Urban heat islands occur due to increases in the extent of artificial surfaces such as concrete, asphalt and high-rise buildings. In this regard, research into the use of satellite thermal infrared images for thermal environment analysis of urban areas is being carried out. However, such analysis of the characteristics of individual land cover with low-resolution satellite images suffers from limitations because land cover patterns in urban areas are complicated. Recently, UAV has been widely used, which can compensate for this limitation as it is able to acquire high-resolution images. In this paper, the accuracy of UAV infrared images is verified and the applicability of UAV in urban thermal environment analysis is examined by comparing the results with land surface temperatures from Landsat 8 thermal images. The results show a high positive correlation of temperature values at 0.95, and no statistically significant difference between the two groups. Comparisons of land surface temperature according to land cover showed that the largest difference observed was $4.63^{\circ}C$ in the Used area, and UAV images with small cell units reflected various surface temperatures. Furthermore, it was possible to analyze the surface temperatures of various green spaces such as wetlands and street tree areas, which can lower surface temperatures in urban areas, with street tree shadows reducing surface temperatures by about $4-6^{\circ}C$. UAV can easily and rapidly measure the surface temperature of urban areas and is able to analyze various types of green spaces. Thus, this is an effective tool for thermal environment analysis in urban areas to aid in the design or management of urban green spaces, as it can allow for land cover and the effects of the various green spaces.

• The Korean Journal of Financial Management
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• v.10 no.1
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• pp.249-280
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• 1993

Recent financial theory views insurance policies as financial instruments that are traded in markets and whose prices reflect the forces of supply and demand. This article analyzes individual's insurance purchasing behavior along with capital market investment activities, which will provide a more realistic look at the tradeoff between insurance and investment in the individual's budget constraint. It is shown that the financial economic concept of insurance cost should reflect the opportunity cost of insurance premium. The author demonstrates the importance of riskless and risky financial assets in reaching an equilibrium insurance premium. In addition, the paper also investigates how the investment income could affect the four established theorems on traditional insurance literature. At the present time in Korea, the price deregulation is being debated as the most important current issue in insurance industry. In view of the results of this paper, insurance companies should recognize investment income in pricing their coverage if insurance prices are deregulated. Otherwise. price competition may force insurance companies to restrict coverage or to leave the market.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.263-268
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• 1997

Purpose : Authors designed a customized Small Bowel Displacement System (SBDS) to displace the small bowel from the Pelvic radiation fields and minimize treatment-related bowel morbidities. Materials and Methods : From August 1995 to Mar 1996. 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized styrofoam compression device which can displace the small bowel from the radiation fields and an individualized immobilization abdominal board for easy daily setup in prone position After opacifying the small bowel with Barium3, the patients were laid Prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The areas of the small bowel included in the radiation fields with and without the SBDS were compared. Results : Using the SBDS, the mean small bowel area was reduced by $59\%;on\;PA\;and\;51\%$ on LAT films (P=0.0001). In six Patients (6/55. $11\%$), it was Possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Only $15\%$ (8/55) of patients treated with the SBDS manifested diarrhea requiring medication. Conclusion : The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and reduce the radiation therapy morbidities. Compliance with setup is excellent when the SBDS is used.