• Journal of Radiation Protection and Research
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• v.44 no.4
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• pp.128-148
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• 2019

Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2-3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.2
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• pp.242-254
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• 2000

Accurate impression is very important to achieve desirable prosthesis and there are many factors in taking a good impression. For example, types of impression material, types of impression tray, impression taking methods and so on. Recently individual tooth tray technique is accepted as obtaining good impression that can be applied to multiple abutment impression, heavy salivated patient, to minimize the effect of natural teeth s undercuts and to reduce pain during cord packing procedures. The purpose of this study was to compare the accuracy according to materials and forms of the individual tooth tray which is clinically applied nowadays. Used materials in experiment were divided into 3 types (acrylic resin. $Futar^{(R)}$ occlusion. $Blu-mousse^{(R)}$) and forms were divided into 2 types (forming occlusal vent hole or not and forming marginal vent space or not). Stone master model from impression body and metal master model were measured by $X-PLAN360d^{(R)}$ to compare occlusal surface discrepancy and marginal discrepancy. The results were as follows: 1. In comparison of occlusal surface discrepancy and marginal discrepancy according to materials, groups with three materials showed no statistical difference 2. In comparison of occlusal surface discrepancy and marginal discrepancy according to occlusal vent hole, groups with occlusal vent hole showed significantly less marginal discrepancy than groups with no occlusal vent hole(p<0.05). 3. In comparison of occlusal surface discrepancy and marginal discrepancy according to 0.5mm-marginal-vent-space, groups with no 0.5mm-marginal-vent-space showed significantly less marginal discrepancy than groups with 0.5mm-marginal-vent-space (p<0.05). In summary these results suggest that individual tooth tray made of 3 types of materials with occlusal vent hole and individual tooth tray made of acrylic resin with no marginal vent space showed good accuracy of impression. In addition, individual tooth tray which is made of bite registration materials may be more useful because of advantage in facility and timesaving aspect of fabrication.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.1
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• pp.12-21
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• 2012

IEEE 802.11 MAC protocol standard, DCF(CSMA/CA), is originally designed to ensure the fair channel access between mobile nodes sharing the local wireless channel. It has been, however, revealed that some misbehavior nodes transmit more data than other nodes through artificial means in hot spot area spreaded rapidly. The misbehavior nodes may modify the internal process of their MAC protocol or interrupt the MAC procedure of normal nodes to achieve more data transmission. This problem has been referred to as a selfish node problem and almost literatures has proposed methods of analyzing the MAC procedures of all mobile nodes to detect the selfish nodes. However, these kinds of protocol analysis methods is not effective at detecting all kinds of selfish nodes enough. This paper address this problem of detecting selfish node using Tsallis-Entropy which is a kind of statistical method. Tsallis-Entropy is a criteria which can show how much is the density or deviation of a probability distribution. The proposed algorithm which operates at a AP node of wireless LAN extracts the probability distribution of data interval time for each node, then compares the one with a threshold value to detect the selfish nodes. To evaluate the performance of proposed algorithm, simulation experiments are performed in various wireless LAN environments (congestion level, how selfish node behaviors, threshold level) using ns2. The simulation results show that the proposed algorithm achieves higher successful detection rate.

• Korean Journal of Clinical Pharmacy
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• v.22 no.3
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• pp.251-259
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• 2012

Ulcerative colitis (UC) is characterized by a life-long chronic course with remissions and exacerbations. Use of biological therapies may reduce or delay the surgical procedures in patients with UC. The aim of this study was to determine the impact of infliximab (IFX) use on the rate of remission, surgical interventions, and the effect on quality of life in patients with moderate to severe UC. Literature was searched for studies that investigated the efficacy of IFX on the rate of remission, colectomy and quality of life (QoL) between January 1990 and June 2012 at MEDLINE, January 1988 and June 2012 at EMbase and others. Eleven trials were included in the meta-analysis; divided into placebo controlled 8 trials and intravenous corticosteroid controlled group 3 trials. In comparison to placebo control groups, patients who received IFX had an odds ratio (OR) of 3.712 (95% CI: 2.714, 5.079) for the short-term clinical remission, and 3.053 (95% CI: 2.044, 4.559) for the rate of long-term remission. In colectomy rate and quality of life (QoL), odds ratio were 0.566(95% CI: 0.387, 0.827) and 0.658 (0.505, 0.811) respectively. Any adverse reactions including infections, infusion reaction, rash and arthralgia were equivalent in both groups. Compared with intravenous corticosteroid controlled group, patients who received IFX had lower remission rate with short-term odds ratio 0.227 (95% CI: 0.033, 1.556) and long-term odds ratio 1.054 (95% CI: 0.317, 3.502) respectively. However, statistical significance was not showed with both two analyses. The higher adverse drug reaction (ADR) rates were occurred in the corticosteroid controlled groups. 73.3% of patients treated corticosteroid reported Cushing-like syndrome with moon face. In conclusion, IFX does increase remission rate and decrease the rate of colectomy in patients with UC without elevating any adverse reactions significantly. IFX also improves QoL in moderate to severe UC patients. It would not exceed the efficacy of intravenous corticosteroid, whereas intravenous corticosteroid also reported high rate of adverse reactions.

• Child Health Nursing Research
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• v.4 no.2
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• pp.193-206
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• 1998

The purpose of this study was to examine the stressors and stress coping styles of 6th grade el ementary school children and to explore the relationship between stressful life events and health symptoms and the effects of coping style which is theoretically considered to mediate the relationship between stress and health symptoms. The study subjects consisted of 329 in 6th grade elementary school children in Cheong-Ju city. Of the 329 subjects, 171 were boys and 158 were girls. For this study, three kinds of questionnaires were adopted as follows ; 1) Feel Bad Scale (FBS) by Lewis et al., 2) lazarus-Folkman's Way of coping questionnaire 3) Hee Sun Shin's Health Symptom questionnaire (HSQ) The researcher visited the school and collected data in the class using the questionnaire method after an explanation of the purpose and procedures was given to the children. Data collection was done for 10 days (from 5th to 15th of July 1997) . The data were analyzed by descriptive statistics, correlation analysis, multiple regression analysis using the SAS statistical program. The results of this study were as follows : 1. The mean score for the FBS was 211.37(range : 77-427), The most severe stressors perceived by children were parental divorce and other's smash or steal of my things. The most frequently experienced stressful life events were conflict with siblings and being scolded for other's fault. 2. The most frequently used stress coping style was the active coping (M=17.85), followed by passive (M=13.64) and magical one (M=13.42). 3. The mean score for the HSQ was 23.30(range : 0-72) The most frequently complained health symptoms were headache and having much worry about everything. 4. There was a significant relationship between stressful life events and health symptoms (r=.60, p<.001). Also, stressful life events were positively related with passive coping(r=.27, p<.001) and magical coping (r=.38, p<.001). Health symptoms were positively correlated with passive coping(r=.33, p<.001) and magical coping (r=.41, p<.001). 5. Stepwise multiple regression analysis revealed that the most powerful predictor was the variable of stressful life events. Health concerns, magical coping style, passive coping style and active coping style accounted for 49.15% of the variance in health symptoms. This study revealed that stressful life events correlated with health symptoms in 6th grade elementary school children and passive coping and magical coping had mediating effects on this relationship. The implication for nursing is that there is a need to develop supportive interventions for high risk population to decrease health problems due to stress.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.464-469
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• 2011

Introduction: As dental implant surgery is becoming increasingly popular, it has become one of the causes for the hypesthesia of the inferior alveolar nerve, along with other surgical procedures, such as a third molar extraction. In addition, it tends to cause legal problems between the operator and patient. Therefore, there must be a proper method that is reliable, objective and economical to assess the nerve impairment. For this reason, an attempt was made to use an Electric Pulp Tester to assess inferior alveolar nerve block anesthesia. Materials and Methods: Thirty patients were tested. Electric pulp testing of the lower jaw skin was performed at the three different times, before anesthesia, at the onset of sensory changes and after 15 minutes waiting from the onset, and on the 10 points of the chin, which produced 10 sections on the skin area. Results: Twenty seven patients (90%) could feel the electric stimulus on the chin at all 10 points before local anesthesia and the scores represent the statistical differences between the right and left points except R4 and L4. After anesthesia, the difference between the right and left points (L3-R3, L4-R4, L5-R5) increased significantly with time but two points (L2, R2) showed no significant difference. The scores on the left chin (L3, L4, L5) increased, whereas the other points (R1-R5, L1, L2) showed no significant differences. Conclusion: This study highlights the potential clinical use of an electric pulp tester for an assessment of inferior alveolar nerve impairment.

• Journal of Korean Medicine Rehabilitation
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• v.26 no.4
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• pp.97-105
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• 2016

Objectives The purpose of this study is to investigate traffic accident patients who were admitted to Korean and Western medicine hospital. Methods According to the medicine record from Dong-eui university, 908 traffic accident patients who were admitted to Korean medicine hospital and Western medicine hospital from 1st January 2011 to 31th July 2016 were analyzed. We classified the patients' sex, age, classification of diseases, hospitalization. Results 1. According to age and sex, the rate of male was 35.4%, and that of female was 64.6% in Korean medicine hospital. However, the rate of male was 46.6%, and that of female was 53.4% in Western medicine hospital. 2. According to admission procedures, the most patients (93.3%) went through out-patient department in Korean medicine hospital and 53.5% of patients went through emergency room in Western medicine hospital. 3. According to principal diagnosis, 'sprain and strain of neck level' was 65.4 percentage Korean medicine hospital and 'intracranial injury' was 63.2 percentage in Western medicine hospital. 4. There was no statistical significant in hospitalization periods between male and female in Korean medicine hospital. However, hospitalization periods of female were longer than that of male in Western medicine hospital. 5. There was no correlation between age and hospitalization period in both Korean and Western medicine hospital. 6. Average hospitalization period of Korean medicine hospital patients were shorter than that of Western medicine hospital patients. 7. According to automobile insurance review organization, hospitalization periods were not significantly different in both Korean and Western medicine hospital. Conclusions It is concluded that there is difference of characteristics between inpatients who were admitted to Korean and Western medicine hospital due to traffic accident.

• Journal of Gifted/Talented Education
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• v.13 no.3
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• pp.19-44
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• 2003

On the basis of Sternberg's the theory of mental self-government, this study investigated the differences in students' thinking styles between gifted and average students and the differences in teachers' thinking styles by school quality (gifted school/ average school), sex, professional teaching experience (as measured by duration), and subject of teaching. The subjects were consisted of 191 gifted high school freshmen, 245 average high school freshmen, and 73 teachers. The results of this study were as follows: First, there were statistical differences in many of thinking styles between gifted and average student school. Gifted students scored higher on the legislative, executive, judicial, global, and hierarchic, internal thinking styles. Second, there were no differences in teachers' thinking styles by school quality (gifted school/ average school). Third, teachers with more professional teaching experience (as measured by duration) tended to score higher on the executive, local, and conservative thinking styles. Fourth, there were no differences in teachers' thinking styles by sex and by subject of teaching. To conclude, the thinking styles of students and teachers can play an important role in teaching and learning in schools. Therefore, we need the cognition of thinking styles of students and teachers for the ideal gifted identification and instructional procedures.

• Korean Journal of Head & Neck Oncology
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• v.14 no.1
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• pp.46-53
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• 1998

Background: Hypopharyngeal cancer represents about one-third the incidence of laryngeal cancer which is the most common cancer in head and neck area. Although there have been numerous reports regarding its clinical and statistical characteristics, more precise and ample data should be collected and analyzed in this country. Objectives: This study was designed to evaluate the pattern and patient's profile of the hypopharyngeal cancer, and we reviewed the treatment outcomes to search for an index of treatment modalities. Materials and Methods: The authors retrospectively analyzed 73 cases of hypopharyngeal cancer treated at Yonsei Medical Center during the 10-year period from 1985 to 1994. Five-year survival rate was calculated according to the primary site, clinical stage and treatment modality. Results: The incidence was predominated in male by 9 to 1 and peak incidence was 6th and 7th decades. Pyriform sinus was the main primary site(80.8%) followed by posterior hypopharyngeal wall(13.7%) and postcricoid area(5.5%). Advanced stage cancers(87.7%) were more common than early stage cancers. Radiotherapy(60.3%) was the most commonly used as primary treatment modality. Neck node metastasis was early occurred even in early stage cancers(61.5%), and overall rate of neck node metastasis was 69.9%. All surgical cases received procedures more than total laryngectomy and partial pharyngectomy. The most common cause of death was primary failure(81.5%) and it was highest in radiotherapy group. Five-year survival rate was significantly high in surgery group(90.9%). The overall 5-year survival rate of hypopharyngeal cancer was 30.3%. Conclusion: High index of suspicion should be required for early diagnosis. Also, surgery may be recommended for the primary treatment modality in advanced stage cancers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.531-538
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• 2017

In the case of hydraulic pressure type fuse, we accept or reject certain product lots by considering the number of defective products in the operating pressure test. Generally, this procedure, known as 'The inspection by attributes', has been most commonly used in the field of quality assurance of products. However, the method of inspection by attributes suffers because it tests more samples than inspection by variables. Even though the quality of the products has remained stable in the process condition, the same number of samples is required for every lot, which wastes time and money. This paper suggests that the lot acceptance procedure is changed from inspection by attributes to inspection by variables. We can calculate the statistical tolerance percent of defectives and compare this to the Acceptable Quality Level (AQL) in order to save money and time. It is also easier to monitor and control the quality of products by using the process capability index and x-bar charts. In conclusion, the procedure delivers mutual benefit to both the customer and the producer by securing high quality products and reference data.