• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.6
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• pp.644-653
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• 2013

In this paper, a formulation for obliquely incident electromagnetic wave has been presented for an analysis of highpower electromagnetic pulse penetration into multilayered dispersive media. Based on generalized models of measured dielectric constants and propagation channels reflecting the Earth's general features, the propagation phenomenon of the obliquely incident early-time(E1) high altitude electromagnetic pulse(HEMP) is analyzed. In addition, the polarization and critical angle are also considered. It is found that the total reflection occurs at an incident angle of about 38 degrees at the soil-rock interface, and that the parallel-polarized E1 HEMP penetrates better than the perpendicular-polarized one. The peak level of the penetrating electric field is found to be 5.6 kV/m at normal incidence, regardless of the type of polarization, and E1 HEMP is greatly reduced near the critical angle. Moreover, the penetrating E1 HEMP is analyzed as a variation of moisture content and depth of materials, resulting E1 HEMP could be useful in determining the levels of shielding required for buried facilities.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.478-490
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• 2017

Objectives: The association of air pollution levels and land-use types with changes in the prevalence of allergic diseases (allergic conjunctivitis, allergic rhinitis, asthma, and atopic dermatitis) was investigated for seven metropolitan cities in Korea Methods: Data on daily hospital visits and admissions (of those under 19 years old) for 2003-2012 were obtained from the National Health Insurance Cooperation. Meteorological data on daily mean temperature, humidity, and air pressure were obtained from the Korea Meteorological Administration. Daily mean or maximum concentration data for five pollutants ($PM_{10}$, $O_3$, $NO_2$, $SO_2$, and CO) as measured at air quality monitoring sites operated by the Ministry of Environment were used. We estimated excess risk and 95% confidence intervals for the increasing interquatile range (IQR) of each air pollutant using Generalized Additive Models (GAM) appropriate for time series analysis. Results: In this study, we observed a significant association between the IQR increases of air pollutants and the prevalence risk of allergic diseases (allergic conjunctivitis, allergic rhinitis, asthma, and atopic dermatitis) in all metropolitan cities after adjusting for temperature, humidity, and air pressure at sea level. Among the air pollutants, $NO_2$ and $PM_{10}$ were associated with the prevalence of asthma, and $O_3$ was associated with only allergic conjunctivitis in regression analysis. However, in GAM analysis considering land-use, $O_3$ and $SO_2$ were associated with allergic conjunctivitis, PM10, O3, NO2, and CO were associated with allergic rhinitis, and $PM_{10}$, $O_3$ and $NO_2$ were associated with asthma in industrial area. Conclusion: This study found a significant association between air pollution and the prevalence of allergic related diseases in industrial areas. More detailed research considering mixed traffic-related air pollution (TRAP) and conducting meta-analyses combining data of the all cities is required.

• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.77-87
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• 2004

In this paper a back-propagation neural network model is developed to estimate the preconsolidation pressure of Korean soft soils based on 176 oedometer tests and 63 piezocone test results, which were compiled from 11 sites - western and southern parts of Korea. Only 147 data were used for the training of the neural network and 29 data, which were not used during the training phase, were used for the verification of trained network. Empirical and theoretical models were compared with the developed neural network model. A simple 4-4-9-1 multi-layered neural network has been developed. The cone tip resistance $q_T$ penetration pore pressure $u_2$, total overburden pressure $\sigma_{vo}$ and effective overburden pressure $\sigma'_{vo}$ were selected as input variables. The developed neural network model was validated by comparing the prediction results of the proposed neural network model for the new data which were not used for the training of the model with the measured preconsolidation pressures. It can also predict more precise and reliable preconsolidation pressures than the analytical and empirical model. Furthermore, it can be carefully concluded that neural network model can be used as a generalized model for prediction of preconsolidation pressure throughout Korea since developed model shows good performance for the new data which were not used in both training and testing data.

• The Journal of Korean Academy of Prosthodontics
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• v.20 no.1
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• pp.51-66
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• 1982

The purpose of this study was primarily to determine the relationship between temporomandibular joint mobility and generalized benign joint hypermobility. The subjects were 85 men and 76 women, who were students of dental and dental hygiene schools, aged 18 to 30 years old. They had no disturbances or complaints of movement of temporomandibular joints and other joints in the body. The joint mobility was measured by a test which is a modification of a method developed originally by Carter and Wilkinson (1964). The mandibular mobility was measured during active and passive maximal opening, laterotrusion, protrusion, and retrusion by Ingervall's method (1970). The obtained results were as follows: 1. The distribution of joint hypermobility disclosed was 4.8% in men and 19.7% in women, and 11.8% of total subjects. 2. The joint mobility index was a mean of 0.37 for men and 0.51 for women in total subjects, and 0.80 for men and 0.73 for women in hypermobile subjects. 3. The angle of passive dorsiflexion of the little finger was greater in the left than in the right hand for both sexes and in hypermobile subjects than in total subjects. 4. There was a positive correlation between the joint mobility index and the angle of passive dorsiflexion of the little finger in total subjects. 5. The joint mobility was greater in women than in men, and in the left than in the right hand. 6. In the active maximal mandibular movements of total subjects, the mean values for the opening capacity was 56.01 mm and 52.04mm, the laterotrusion mean 8.07 and 8.08, the protrusion mean 8.72 and 8.24, and the retrusion mean 0.48 and 0.49 for men and women respectively. 7. In the passive maximal mandibular movements of total subjects, the mean values for the opening capacity was 59.07mm and 54.85mm, the laterotrusion mean 8.90 and 9.12, the protrusion mean 10.03 and 10.00, and the retrusion mean 0.69 and 0.72 in men and women respectively. The active and passive maximal opening capacity was larger in men than in women but in the other movements there were no significant differences between men and women. 8. The range of active and passive maximal mandibular movements of hypermobile subjects tended to be larger in men but no significant difference in women compared with that of total subjects. 9. The range of maximal mandibular movements was increased more in passive than in active.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.2
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• pp.251-255
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• 2000

The strict meaning of the term retarded eruption is that tooth eruption is delayed compared to its developmental stage. The etiological factors for it may be local, systemic or genetic. Its pathogenic mechanism is unknown in most cases. In cases of generalized retarded eruption without any clear reason, the general growth and development seems normal in all aspects and the teeth usually keep the normal eruption sequence. Usually the primary teeth may often be extracted hoping to provoke the eruption of the retarded teeth, only to be proved a failure. Consequently, the patient will be without teeth for many years, with loss of esthetics, loss of occlusal height and resorption of alveolar process. The primary goal in the treatment may therefore be to keep and maintain the primary teeth in good condition until they are naturally shed. This observation was done on 10 year 1 month old patient who were diagnosed as idiopathic retarded eruption through both radiographic and systemic examination and follow-up observation was done for 11 month.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.4
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• pp.328-334
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• 2014

Gingival fibromatosis is a rare oral condition that is characterized by proliferative fibrous overgrowth of the attached gingiva, the marginal gingiva, and the interdental papilla, typically presenting in the growth period. A case of a 27-month-old girl with a generalized severe gingival overgrowth is described herein. The patient had no known systemic disease, but enlarged gingival tissue had gradually covered her teeth. The excess gingival tissue was removed by conventional gingivectomy, which involved extraction of the retentive primary teeth under general anesthesia when she was 5 years old. Post surgical follow-up at 18 months after the surgery demonstrated no recurrence. Resectional surgery of the enlarged gingival tissue is the treatment choice for gingival fibromatosis, although there is a high risk of recurrence. More frequent professional follow-ups and oral hygiene instruction might be required. A delay in the surgical treatment may have significant consequences for the patient, such as primary dentition retention and consequent delay in the eruption of the permanent teeth, difficulties in mastication and phonation, malpositioning of the teeth, and psychological problems. Early surgical treatment should be performed according to the severity of enlargement.

• Culinary science and hospitality research
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• v.10 no.3
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• pp.97-118
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• 2004

As the economy grows rapidly and the national income level increases, the service industry has become more important and its size gets larger. Especially, the food industry undertakes a continuing growth of consumer expenditures through no nationalization of food, consumers varying patterns of eating out, and individualization. However, it includes many problems with improving service quality towards customers owing to the absence of systems and philosophy to realize customer satisfaction management Therefore, this study conducted a study with Korean traditional restaurant customers to measure their perceived service quality, to verify what factors most influence consumer satisfaction, and to suggest ways to meet the costumer needs by integrating the study results and developing high service quality. To sum up the results of this study, Korean traditional restaurant visitors evaluated three dimensions of service quality overall favorably. Interestingly, background music received a lower level of satisfaction. This implies that the Korean traditional restaurant managers do not do a fine performance in managing music as an ambient element to evoke the atmosphere of the restaurant. Customers showed a lower satisfaction with menu price among the factors measuring product quality. As a result of this study, several suggestions have been made as follows: First, it is necessary for the Korean traditional restaurants to provide systematic employee training to instigate a service culture of customer focus. Secondly, it is important to develop traditional foods using ingredients produced in the region based on a literature review of food in Gyeongju, Silla. Thirdly, it is an urgent task to develop regional menus to revitalize the restaurant business. Fourthly, it is important to provide safety food through systematic sanitary administration. Lastly, it is necessary to limit the number of menu items and attempt specialization of them. Such an attempt with specialized menu items will help their food taste and quality improve and thereby reduce inventory burdens. However, this study has a few limitations. Since this study conducted a survey of the restaurants which provides only Korean traditional food in Gyeongju, not all the restaurants in it, there is a limitation in measuring customer satisfaction with service quality. Therefore, the study results cannot be generalized to all the restaurants in Gyeongju and the nation. Finally, this study suggests that studies on the relationships between customer satisfaction and menu price and customer value system or further customer satisfaction studies with Korean traditional restaurants should be continued.

• 대한공업교육학회지
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• v.33 no.2
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• pp.26-43
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• 2008

The purpose of this study is to survey of specialists cognition to authorize credits for the same subjects in entering a department of the same area in college among technical high school graduates. Today with generalized college education, about 80% of technical high school graduates enter college. Therefore, authorization of credits for the same subjects is necessary to reduce educational waste in terms of articulation among technical high schools, junior colleges and universities. In this study, a survey was conducted with 100 specialists in technical education, including technical high school teachers, researchers, and professors at junior college or technical college in university, getting answers from 84 subjects (81.25%). The results of this research can be summarized as follows: First, it is valid to authorize credits for all practical subjects completed in technical high school when technical high school graduates enter the same department at college but most of junior college professor unsuitable response. Second, it is valid to authorize credits through its own prescribed test for the same subjects when technical high school graduates enter the same department of engineering at junior college or technical college in university but opposed 62.5% of junior college professor. Third, it is most of respondent valid to authorize credits for the same subjects if results of its own examination for authorization by university are at a fixed level or higher when technical high school graduates are admitted as a junior at the same department in technical college of university after graduation from the same department at junior college.

• 대한공업교육학회지
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• v.34 no.1
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• pp.19-43
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• 2009

An ideology what a modern society seeks is lifelong employment through lifelong learning. The single word which draws the attainment is lifelong vocational competency development. This study is designed for exploring its possibility and limit of a redesign of it, and tries to propose efficiently a redesign idea of a vocational educational path. To this end, it was analyzed by a subject for a national human resource foundation plan and a lifelong bocational competency development foundation plan. In addition to that, it was covered a structure and content analysis of main laws and regulations which are a base of policy making. An educational path could be divided into an area of formal education system, an area of workplace for labors, and an area of lifelong vocational competency development. And the insights were drawn by pulling apart an operational situation of main organizations and a recurrent process of the educational path. The redesign plan of a vocational education path we did analyze to activate lifelong vocational competency development system is deduced as following. Firstly, it should be re-organized with a direction towards an effective manpower training to be linked with skills and demands required by an industry. Secondly, it should be generalized for a model of recurrence between work and learning and its alternation for lifelong vocational competency development. Thirdly, it should create a cluster in the region for lifelong vocational competency development so that it is to form an efficient network to have a division of labor and its liaison with cooperative relationship.

• Anxiety and mood
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• v.10 no.2
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• pp.176-181
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• 2014

Objective : Despite high prevalence and effective treatments of panic disorder, lots of patients are not properly treated due to lack of awareness of the disorder. This study summarizes and presents the results from Public Awareness Survey of Panic Disorder during the Mental Health Exposition held in Seoul in April, 2014. Methods : A total of 401 participants who visited the booth of the Korean Academy of Anxiety Disorder agreed and completed the survey. The questionnaires comprised of three sections; first, after given a case of patient with panic disorder, participants were asked to choose a diagnosis and treatment options. Second, participants were asked to differentiate the symptoms of panic disorder from those of other mental disorders and answer where they acquired the knowledge of the disorder. Third, visual analogue scales were used to get more detailed information for several issues about panic disorder. The incidence and ratio for each question were provided and compared. Results : Among the participants, 78% reported a patient within the case need treatment, and 30% accurately recognized it was panic disorder. As for treatment needed, 40% selected psychotherapy by psychiatrists, 28% chose counseling by psychologist, 23% said that they can overcome it by self-care. Only 2% of participants selected the pharmacotherapy as treatment needed. Approximately 40% of participants have encountered information about the disorder from gossips of celebrities, 32% from mass-media, and merely 6% from medical professionals. About 80% of participants could discriminate the symptom of panic disorder from those of depression, schizophrenia, or generalized anxiety disorder. Conclusion : Our results suggest that substantial proportions of participants have the awareness of panic disorder, while as for treatment they were strongly biased against pharmacologic treatments. Most of their source of the awareness was not relied upon professional information. Efforts for giving correct information and increasing public awareness of panic disorder are needed to bridge a gap between professionals and general public.