• The Journal of Korean Society for Radiation Therapy
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• v.18 no.2
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• pp.81-87
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• 2006

Purpose: Few researches have been peformed on the dose distribution of the moving organ for radiotherapy so far. In order to simulate the organ motion caused by respiratory function, multipurpose phantom and moving device was used and dosimetric measurements for dose distribution of the moving organs were conducted in this study. The purpose of our study was to evaluate how dose distributions are changed due to respiratory motion. Materials and Methods: A multipurpose phantom and a moving device were developed for the measurement of the dose distribution of the moving organ due to respiratory function. Acryl chosen design of the phantom was considered the most obvious choice for phantom material. For construction of the phantom, we used acryl and cork with density of $1.14g/cm^3,\;0.32g/cm^3$ respectively. Acryl and cork slab in the phantom were used to simulate the normal organ and lung respectively. The moving phantom system was composed of moving device, moving control system, and acryl and cork phantom. Gafchromic film and EDR2 film were used to measure dose ditrbutions. The moving device system may be driven by two directional step motors and able to perform 2 dimensional movements (x, z axis), but only 1 dimensional movement(z axis) was used for this study. Results: Larger penumbra was shown in the cork phantom than in the acryl phantom. The dose profile and isodose curve of Gafchromic EBT film were not uniform since the film has small optical density responding to the dose. As the organ motion was increased, the blurrings in penumbra, flatness, and symmetry were increased. Most of measurements of dose distrbutions, Gafchromic EBT film has poor flatness and symmetry than EDR2 film, but both penumbra distributions were more or less comparable. Conclusion: The Gafchromic EBT film is more useful as it does not need development and more radiation dose could be exposed than EDR2 film without losing film characteristics. But as response of the optical density of Gafchromic EBT film to dose is low, beam profiles have more fluctuation at Gafchromic EBT. If the multipurpose phantom and moving device are used for treatment Q.A, and its corrections are made, treatment quality should be improved for the moving organs.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.2 no.2
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• pp.68-73
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• 2009

Purpose: We retrospectively studied the outcomes of the shoulder impingement syndrome for the treatment of the ultrasound-guided subacromial bursal steroid injection. Materials and Methods: Sixty-six shoulders of sixty-two patients with shoulder impingement syndrome treated from March, 2006 to April, 2009 were involved in this study. All cases underwent standardized, nonoperative treatment protocol consisting of 5~12 MHz high resolution ultrasound-guided local steroid injection into the subacromial bursa in modified Crass position. The shoulder range of motion, VAS score and impingement signs were evaluated during the initial and 1year visits. After injection, shoulder elevation exercise was encouraged. Statistical analysis with ANOVA model and Tukey's post-hoc test with the significance level at 5% were performed using SAS program. Results: All cases showed improved range of motion without limitation of shoulder function at immediate post-injection, 6-week, 3-month and 1year visits. The average VAS score at one year follow-up decreased to 2.85 from 6.47 before injection. In all cases the impingement signs became negative immediate after injection. However, 6 cases showed positive impingement signs after 6-week, which became negative after reinjection. The range of motion and VAS score were improved at one-year follow-up compared to initial visit (p<0.0001). No complication was noted at all follow-up period. Conclusion: Ultrasound-guided subacromial steroid injection alleviated the need of surgery, because it was successful in all our cases to improve pain and function of the shoulders until one year follow-up period.

• Journal of environmental and Sanitary engineering
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• v.18 no.1
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• pp.51-57
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• 2003

Indoor air quality(IAQ) in workplace and residential environments has been concern of people. Recently, Ministry of Environment in Korea has recognized the potential risk on the healthy effect related to indoor air pollution at home. Therefore, the purpose of this study was performed to measure the indoor air pollutants of IAQ at different homes and investigate to compare the perception of IAQ recognition at home from questionnaire survey in Seoul. We estimated the IAQ of selected 6 homes based on site region and housing type. The indoor air pollutants and parameters such as temperature, relative humidity, respirable suspended particulate matter($PM_{10}$), formaldehyde(HCHO), total bacteria counts, carbon monooxide(CO) and carbon dioxide($CO_2$) were monitored for summer and winter. In monitoring results, the respirable suspended particulate matter(($PM_{10}$) and indoor airborne bacteria level of home 5 and 6 were higher than the standard of the public $150{\;}{\mu}g/m^3$ and $500{\;}{\mu}g/m^3$, the level formaldehyde(HCHO) was exceed 0.1 ppm of the standard of Korea at all monitored homes. In statistics analysis, we could find a correlation between the building age and the concentration of CO, TBC were significant at 0.01 level and Relative Humidity was significant at 0.05 level for summer. Finally, the important air pollutants of IAQ in home were HCHO and total bacteria counts(TBC). And we performed a questionnaire survey of 500 people about their awareness for the importance of IAQ in our home during same period. In results, all most response of occupant has recognized the importance of IAQ at home. Therefore, it can be concluded that the IAQ of selected 6 home studied was perceived as acceptable, it is recommended that the government related IAQ was suggested the guideline and control of IAQ problems, and the occupants need to be effort to reduce the exposure of sources to undesirable pollutants.

• Journal of the Korean Wood Science and Technology
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• v.48 no.3
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• pp.271-282
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• 2020

Sewage treatment plants are social infrastructure of cities. The sewage distribution rate in Korea is reaching 94% based on the sewage statistics based in the year of 2017. In Korean sewage treatment plants, use of PAC (Poly Aluminum Chloride) accounts for 58%. It contains a large amount of impurities (heavy metal) according to the quality standards, however, there have been insufficient efforts to reinforce the standards or technically improve the quality, which resulted in secondary pollution problems from injecting excessive coagulant. Also, the increase in the use of chemicals is leading to the increases in the annual amount of sewage sludge generated in 2017 and the need to reuse sludge. As such, this study aims to verify the possibility of reusing sludge by evaluating the stability of heavy metals based on the injection of coagulant mixture during water treatment which uses the torrefield wood powder and natural materials, and evaluating the sedimentation and heating value of sewage sludge. As a result of analyzing heavy metals (Cr, Fe, Zn, Cu, Cd, As, Pb, and Ni) from the coagulant mixture and PAC (10%), Cr, Cd, Pb, Ni, and Hg were not detected. As for Zn, while its concentration notified in the quality standards for drinking water is 3 mg/L, only a small amount of 0.007 mg/L was detected in the coagulant mixture. Maximum amounts of over double amounts of Fe, Cu, and As were found with PAC (10%) compared to the coagulant mixture. Also, an analysis of sludge sedimentation found that the coagulant mixture showed a better performance of up to double the speed of the conventional coagulant, PAC (10%). The dry-basis lower heating value of sewage sludge produced by injecting the coagulant mixture was 3,378 kcal/kg, while that of sewage sludge generated due to PAC (10%) was 3,171 kcal/kg; although both coagulants met the requirements to be used as auxiliary fuel at thermal power plants, the coagulant mixture developed in this study could secure heating values 200 kal/kg higher than the counterpart. Therefore, utilization of the coagulant mixture for water treatment rather than PAC (10%) is expected to be more environmentally stable and effective, as it helps generating sludge with better stability against heavy metals, having a faster sludge sedimentation, and higher heating value.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.381-386
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• 2010

Background: Sternal wound infection (SWI) is an important complication after cardiac surgery. The aim of this study was to investigate the predictors affecting sternal wound infection and preventive factors including short term Vancomycin therapy in patients who underwent coronary artery bypass grafting (CABG). Material and Method: A retrospective study was done using data collected from January 2001 through December 2007. This included 219 patients who had isolated CABG. The definition of SWI was documentation from a microbiological study and a requirement for simple closure or other surgical revision. Result: The overall incidence of SWI was 7.8% (n=17). The causative organisms were methicillin resistant Staphylococcus aureus (MRSA, n=13), methicillin resistant Staphylococcus epidermidis (n=2), Pseudomonas aeruginosa (n=1), and Candida albicans (n=1). Ten cases had deep sternal wound infection with mediastinitis; 7 cases had a superficial wound infection. Infection-related mortality was low (1/17; 6%). Diabetes mellitus (p=0.006) and smoking history (p=0.020) were factors that predicted high risk. Short term use of vancomycin decreased the incidence of MRSA-associated SWI (p=0.009). For treatment, curettage and rewiring or flap were needed in most cases (88%, n=14). Conclusion: Patients who had diabetes mellitus and a smoking history need careful management. Short term use of vancomycin is effective for prevention of SWI with MRSA.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.364-374
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• 2010

Background: We assessed the early and mid-term results of the modified Norwood procedure for first-stage palliation of hypoplastic left heart syndrome (HLHS) and its variants to identify the risk factors for hospital mortality. Material and Method: Between March, 2003, and December, 2009, 23 patients (18 males and 5 females) with HLHS or variants underwent the modified Norwood procedure. The age at operation ranged from 3 to 60 days (mean, $11.7{\pm}13.2days$) and weight at operation ranged from 2.2 to 4.8 kg (mean, $3.17{\pm}0.52kg$). We used a modified technique that spared the anterior wall of the main pulmonary artery in 20 patients. The sources of pulmonary blood flow were RV-PA conduit in 15 patients (group I) and RMBTS in 8 (group II). Follow-up was completed in 19 patients (19/20, 95%) in our hospital (mean $26.0{\pm}22.8months$). Result: Early death occurred in 3 patients (3/23, 13%), of whom 2 had TAPVC. Fourteen patients underwent subsequent bidirectional cavopulmonary connection (BCPC, stage 2) and seven underwent the Fontan operation (stage 3). Three patients died between stages, 2 before stage 2 and one before stage 3. The estimated 1-year and 5-year survival rates were 78% and 69%, respectively. On multivariate regression analysis, aberrant right subclavian artery (RSCA) and associated total anomalous pulmonary venous connection (TAPVC) were risk factors for hospital mortality after stage 1 Norwood procedure. Conclusion: HLHS and its variants can be palliated by the modified Norwood procedure with low operative mortality. Total anomalous pulmonary venous connection adversely affects the survival after a stage 1 Norwood procedure, and interstage mortality rates need to be improved.

• Radiation Oncology Journal
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• v.27 no.1
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• pp.42-48
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• 2009

Purpose: The introduction of image guided radiation therapy/four-dimensional radiation therapy (IGRT/4DRT) potentially increases the accumulated dose to patients from imaging and verification processes as compared to conventional practice. It is therefore essential to investigate the level of the imaging dose to patients when IGRT/4DRT devices are installed. The imaging dose level was monitored and was compared with the use of pre-IGRT practice. Materials and Methods: A four-dimensional CT (4DCT) unit (GE, Ultra Light Speed 16), a simulator (Varian Acuity) and Varian IX unit with an on-board imager (OBI) and cone beam CT (CBCT) were installed. The surface doses to a RANDO phantom (The Phantom Laboratory, Salem, NY USA) were measured with the newly installed devices and with pre-existing devices including a single slice CT scanner (GE, Light Speed), a simulator (Varian Ximatron) and L-gram linear accelerator (Varian, 2100C Linac). The surface doses were measured using thermo luminescent dosimeters (TLDs) at eight sites-the brain, eye, thyroid, chest, abdomen, ovary, prostate and pelvis. Results: Compared to imaging with the use of single slice non-gated CT, the use of 4DCT imaging increased the dose to the chest and abdomen approximately ten-fold ($1.74{\pm}0.34$ cGy versus $23.23{\pm}3.67$cGy). Imaging doses with the use of the Acuity simulator were smaller than doses with the use of the Ximatron simulator, which were $0.91{\pm}0.89$ cGy versus $6.77{\pm}3.56$ cGy, respectively. The dose with the use of the electronic portal imaging device (EPID; Varian IX unit) was approximately 50% of the dose with the use of the L-gram linear accelerator ($1.83{\pm}0.36$ cGy versus $3.80{\pm}1.67$ cGy). The dose from the OBI for fluoroscopy and low-dose mode CBCT were $0.97{\pm}0.34$ cGy and $2.3{\pm}0.67$ cGy, respectively. Conclusion: The use of 4DCT is the major source of an increase of the radiation (imaging) dose to patients. OBI and CBCT doses were small, but the accumulated dose associated with everyday verification need to be considered.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.95-111
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• 2004

This research sought to determine the status of the installation and operation of composting facilities of domestic public resource-making facilities and come up with corresponding improvement measures. The composting facilities were the most extensively installed of related facilities with over a 0.5 ton treated volume per day. The monthly and yearly carry-in volume of food waste were found to stand at 1,101.7 tons per day and 930.9 tons per day, thus falling short of the average planned volume of 1,270.9 tons. Many composting facilities, which were installed in areas for which factory registration were not approved, did not get approvals. Composting facilities underwent operation stoppage mainly due to faulty fermentation and crushing equipment. Mainly metals contained in food waste caused faults to the crushing equipment, thus requiring a facility designing against faults and corrosion. The initial water content was found to stand at 50-60%, thus complying with the requirement. However, since the composting food waste had an appropriate mixture of sawdust, food waste, and returned compost, it should meet the initial conditions. For fermentation facilities, the duration time for fermentation was 15 days, and post-fermentation tanks required 21 days of duration time, thus establishing the minimum criteria. However, some facilities did not meet the requirements, taking more time in decomposition, thus suggesting a need to determine the duration time according to facilities. In composting food waste, microorganism-based thermal oxidizer-operated fermentation tanks should be used to ensure an economic operation. On the contrary, 14 out of 25 survey targets heated fermentation tanks in any form. These thermal facilities contain the growth of bacteria, lowering chemical reaction in composting; thus composting facilities should be basically designed to use microorganism-based thermal oxidizers in drying water. An average daily volume of food waste and supplementary materials that was injected in producing compost was 22.8 tons. This volume produced 7.3 tons of compost per day, decreasing 68%. Properties of produced compost were analyzed by its color, absence or presence of remaining decomposition heat, and smell, to assess the quality. As a result, the composting process was not properly installed nor operated in about 50% of composting facilities. Compost should be produced to be soil-friendly.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3769-3776
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• 2016

Background: Breast cancer is the leading cause of cancer deaths among women worldwide. High breast cancer mortality has been attributed to lack of public awareness of the disease. Little is known about the level of knowledge of breast cancer in Central African Republic. This study aimed to investigate the knowledge of health professionals on breast cancer. Materials and Methods: This cross-sectional study was conducted among 158 health professionals (27 medical; 131 paramedical) in 17 hospitals in Bangui using a self-administered questionnaire. Descriptive statistical analysis, Person's ${\chi}^2$ test and ANOVA were applied to examine associations between variables with p < 0.05 being considered significant. Results: Data analyzed using SPSS version 20 indicates that average knowledge about breast cancer perception of the entire population was 47.6%, diagnosis method 45.5%, treatment 34.3% and risk factors 23.8%. Most respondents (65.8%) agreed that breast cancer is important in Central African Republic and that family history is a risk factor (44.3%). Clinical assessments and mammography were considered most suitable diagnostic methods, and surgery as the best treatment. The knowledge level was significantly higher among medical than paramedical staff with regard to risk factors, diagnosis and treatment. However the trainee group had very high significant differences of knowledge compared with all other groups. Conclusions: There is a very urgent need to update the various training programs for these professionals, with recommendations of retraining. Health authorities must create suitable structures for the overall management of cancer observed as a serious public health problem.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.8 no.1
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• pp.57-69
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• 1997

Objective：At the present time in Korea, for a considerable proportion of children and adolescent, delinquent behavior and violence has become as a way of life in their lives and a major social problem issue as well. The contributing factors to this problem were assumed to be the negative interaction between family environment and character of adolescent. The purpose of this study is to search the relationship between these constructs and juvenile delinquency. Method：Data were collected through questionnaire survey over a period of 2 months. Subjects served for this study consisted of 1,863 adolescents including 657 delinquent adolescents and 1,206 student adolescents in Korea, sampled from Korean student population and delinquent adolescent population confined in juvenile corrective institutions, using proportional stratified random sampling method. Their age ranged between 12 and 18 years. Data were analysed by IBM PC using SAS program. Statistical methods employed were Chi-square and principal component analysis. Results：The results of this study were as follows：Inconsistency by parental child rearing patterns tended to affect delinquent behavior among delinquent adolescents. On the other hand, adolescent students were consistently reared by their parent with democratic, flexible, trusting their children and reward-oriented attitudes. In comparison of both parents in the degree of influence on their children, it was revealed that paternal child rearing pattern was more influential on their children’s behaviors than maternal’s. The psychological instability of family, disharmonious parent-child relationships tended to be contributing to delinquent behavior among delinquent adolescents. Especially, It was an interesting finding that student’s mother is the higher employed than delinquent’s mother. However working mother was more prevalent in the student’ adolescents than in student adolescents in previous studies. The delinquent adolescents have more depressive trend, more complaints of psychosomatic symptoms, the higher degree of need frustration, the more maladaptive and antisocial personality pattern than student adolescents. Conclusion：Recently, many studies on association between family factor, character of adolescent and juvenile delinquent behavior have produced relatively consistent results. This study showed that family environment and character trait of adolescent also were linked with delinquent behavior such as smoking, drinking, runaway and physical assaults etc. The results of this survey may provide impetus for future speculation and study of correlation or reciprocal interaction between family factor, character trait of adolescent and delinquent behavior during adolescence and beyond.