• Journal of the Society of Naval Architects of Korea
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• 제33권1호
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• pp.27-39
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• 1996

The effects of free surface and a strut on the lifting characteristics on a fin attached at the mid-chord of the strut are investigated experimentally in a circulating water channel. Variation of lift force on the fin is investigated with respect to free stream velocity(V), angle of attack of the fin(${\alpha}$) and ratio of the submergence depth of the fin to the chord of the fin(H/C). Attentions are focused on the lifting characteristics of the fin at shallow depths of submergence. Visualization of the free surface deformation along the strut and of the streamline about the fin is made in order to examine the inflow angle to the fin. Lift force on the fin alone i.e. in absence of the strut is also measured to investigate the difference in lifting characteristics of the fin caused by the strut. The results show that lift forces over the fin are largely affected by a free surface in the case of small submergence ratios(HiC<3.0). For HiC>5.0, the effects of the free surface are negligibly small. The inflow angle to the fin is significantly influenced by the strut and flow speed at the shallow depths of submergence. The deformation of the free surface is largely governed by the waves generated by the strut. However, for small submergence depths, the effects of the fin are found also significant.

• The Journal of Fisheries Business Administration
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• 제45권2호
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• pp.39-59
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• 2014

Recently the rapid changes of the social environment make both university and every each department should have to renovate and adjust all of the educational components. The most dominant and issuable change of business administration education is the Business Education Accreditation which was certified by the KABEA(Korean Association of Business Education Accreditation). And the only two department of fisheries business administration which in Gyeongsang National University and Pukyong National University has been accredited recently. Though The department of fisheries business administration in Korea has been influenced by that Accreditation, there is few research and analysis on educational change. So it is very important that research on the curricular constitution and change of the curriculum for considering the its own effect and influence. This paper aims to explore the curricular constitution, change and course fulfillment of fisheries business administration after the business education accreditation based on the case of the department of fisheries business administration in Gyeongsang National University. The analysis of fisheries business administration change will help develop sustainable curriculum and give more guideline for identifying the core of fisheries business administration. The method of analysing that in this research has adopt the social network analysis(SNA) and automated software tool which is the most dominant technique in contents analysis including the Krkwics and Pajek. The SNA is evaluated that most popular, rigorous and firm methodology for analyzing, examining and revising some concepts or objects in the context of semantics. The result of this study shows that the ratio of fisheries business administration class has been decreased but still the most fulfilled course. And English mediated class has been avoided though that sort of the class has been increased. In the view point of course fulfillment, it has been potential and inefficient problems that some classes that including financial related and accounting related class would not been accomplished appropriately. The findings of a graduate depth interview which has been done about 4 years for understanding that student show that there's some recognition gap of fisheries business administration in staffs of human resource management. And the level of job satisfaction in fisheries business still somewhat low and even worse the chance of recruitment also unsteady.

• Journal of agricultural medicine and community health
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• 제40권2호
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• pp.80-92
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• 2015

Objectives: To clarify the association between dust from large construction sites and allergic and respiratory conditions among residents in Sejong city. Methods: We included 379 individuals older than 50 years from three areas of Sejong city; two areas near construction sites and one area for a comparison. Prevalence of self-reported allergic and respiratory conditions was compared across the three areas using logistic regression to adjust for covariates including age, gender, smoking, and educational attainment. A total of 16 individuals were interviewed to take details of the residents' experiences of construction work. Results: Those living in the nearby areas around construction sites were generally found to have the increased prevalence for all allergic and respiratory conditions. Odds Ratio(OR)s for cough and sneezing among the six symptoms and allergic rhinitis among the three diagnosed diseases reached statistical significance but only OR for cough remained significant after adjustment: adjusted OR for cough was 2.63 (95% CI, 1.07-6.46). Two relevant themes emerged from semi-structured interview were; 1) most residents from the affected area reported a considerable level of exposure to construction dust, 2) about half of them noted that construction dust influences allergic- and respiratory health. Conclusions: General pattern provides suggestive evidence that living close to construction sites may be positively associated with elevated risks of allergic and respiratory conditions. Efforts should be made to establish preventive measures and a comprehensive in-depth health impact assessment on this issue.

• The korean journal of orthodontics
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• 제27권4호
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• pp.523-538
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• 1997

In order to investigate TMD prevalence in malocclusion patients and to study its relationship with occlusal factors, 205 malocclusion patients (M67, F138, 6Y1M-46Y8M) were examined. The following examinations were carried out, Questionnaire personal history, TMD symptoms, and the associated factors Clinical examination : TMJ sound and maximum mouth opening Orthopantomogram : condyle abnormalities, length of Co'-Inc' and Co'-Go', ratio Co'- Inc'/ Co'-Go', and depth of antegonial notch Transcranial view limitation of anterior movement of condyle Model Angle classification, overjet, overbite, midline discrepancy, missing of posterior teeth, posterior crossbite, attrition of palatal cusp of maxillary molars, crowding/spacing The results could be summarized as follows, 1. The prevalence of TMD showed that Helkimo Anamestic Inder(Ai) 0 was $46.8\%$, Ai I was $22.0\%$, Ai II was $31.2\%$ and subjective symptoms increased with aging (p<0.001) and were frequent in females (p<0.05). 2. Flattening ($4.4\%$) was the most frequent condyle abnormality on Orthopantomogram, and $8.3\%$ of subjects showed some abnormalities on Orthopantomogram. 3. The cases with neck and shoulder pain (p<0.001), clenching, lip biting (p<0.01), and headache (p<0.05) showed higher scores of Ai. 4. Angle class II showed high frequency of condylar abnormalities on Orthopantomogram, and subjects whose palatal cusp of maxillary molars had been attrided had the tendency to show high hi scores (p<0.05). The other occlusal factors had nothing to do with the symptoms of TMD. 5. In the cases that 1)the value of Co'-Inc', Co'-Go' or Co'-Inc'/Co'-Go' were low or 2)the differences of Co'-Go' or Co'-Inc'/Co'-Go' between the right and the left were large, condylar abnormalities were frequently obserbed on Orthopantomogram.

• Journal of the Korean Institute of Gas
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• 제16권2호
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• pp.18-24
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• 2012

This research seeks to evaluate damage on type II gas cylinder by an acoustic emission test when executing 20000 cycles fatigue test and thereafter burst test. Used gas cylinders in the experimental are three types as follows; one is sound cylinder, others are cylinders which contain longitudinal and transverse artificial defect. The size of artificial defect is a depth of 3 mm, width of 3 mm and length of 50 mm. In the case of the cylinder which artificial defect, unlike the expectation that it will burst in low pressure, the burst pressure of the cylinder did not differ much according to whether or not there were defects. However, when there was longitudinal defect, the location of burst was near the location of defect. This leads to the effect in which the thickness of the composite material becomes thinner according to the length of the longitudinal defect and this is judged to have an effect on the location of initiation and growth of crack in the liner. Also, for the acoustic emission signal, when there is longitudinal defect, the ratio of an event occurring at defect position among overall hits is more than 50 %, and the source location also accords very precisely with defect position.

• Journal of Environmental Health Sciences
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• 제40권5호
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• pp.413-424
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• 2014

Objectives: The purpose of this study was to seek measures for improvement and management of farm work safety and health by conducting questionnaire surveys and on-site investigations to ascertain the present state of occurrence of safety accidents and safety and health management levels among swine farmers. In particular, the purpose of this study is to provide basic data for the establishment of measures for the management of safety and health suitable to the characteristics of related working environments. Methods: Questionnaire surveys were conducted among 223 farmers engaged in swine farming in 14 regions, and 10 farms were visited in order to implement multilateral methods, including in-depth interviews, along with field surveys. Results: The surveys indicated that 26.2% of all respondents experienced farm-work related safety accidents and body-reaction related accidents showed a high ratio at 31.1% of all respondents. With regard to cause materials of safety accidents, work other than that directly related to swine raising showed high ratios of safety accidents, with pigsty facility related accidents at 26.6%. Although most workers recognized the dangers latent in the working environments, their behavior and responses to the prevention of safety accidents were still insufficient due to a lack of understanding of safety and health management. In the survey on the present state of personal hygiene and wearing of protective equipment, workers were found to have been exposed to dangerous and harmful environments both inside and outside pigsties, but the actual states of their wearing protective safety equipment were very poor. Conclusion: Given the results of this study, swine farmers well recognize problems in their control of safety accidents and management of safety and health, but their knowledge about safety and health education and management guidelines was insufficient. Therefore, safety and health education, public relations, and customized personal protective equipment suitable for swine raising work should be developed in order to address the foregoing problem.

• Journal of Korean Tunnelling and Underground Space Association
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• 제19권2호
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• pp.231-248
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• 2017

Government plans to construct a double-deck tunnel under a portion of Gyeongbu Expressway that will solve traffic problems and could also be used as a flood storage facility. Divergence tunnels connect the main tunnel to the urban areas and their construction effects on adjacent structures at shallow depth need to be analyzed. This study primarily includes the numerical analysis of construction effects of divergence tunnels on utility tunnels. The utility tunnel was analyzed for three cases of volume loss applied to the divergence tunnel and two cases of the angle between main tunnel and divergence tunnel ($36^{\circ}$ and $45^{\circ}$). The results show that the more the volume loss was applied and the shorter the distance was between utility tunnel and divergence tunnel, the more the utility tunnel was affected in terms of induced displacements, angular displacement and stability. The worst scenario was found out to be the one where the angle between main tunnel and divergence tunnel was $36^{\circ}$ and the distance between divergence tunnel and utility tunnel was 10 m, resulting in the largest displacement and differential settlement at the bottom of the utility tunnel. A relationship between the angular displacement and the distance to diameter ratio was also established.

• Journal of the Korean Magnetics Society
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• 제11권3호
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• pp.104-108
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• 2001

The effect of specular electron scattering on natural oxidation of free layer in NiO spin valves have been investigated. The magnetoresistance (MR) ratio and the exchange biasing field ( $H_{ex}$) of NiO(600 $\AA$)Ni$_{81}$$Fe_{19}$(50$\AA$)/Co(7 $\AA$)/Cu(20 $\AA$)/Co(7 $\AA$)Ni$_{81}$$Fe_{19}$(70 $\AA$) spin valves were increased from 4.9 % to 7.3 %, and 110 Oe to 170 Oe after natural oxidation in the atmosphere for 80 days, respectively. The sheet resistivity p decreased from 28$\mu$$\Omega$m to 17$\mu$$\Omega$m, but $\Delta$$\rho$ did not almost change after the oxidation. The spin valves enhanced by the specular electron scattering in the natural]y Co/NiFe/NiFe $O_{x}$ free layer were confirmed from the depth profiles using Auger electron spectroscopy.scopy..

• Korean Journal of Plant Taxonomy
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• 제38권4호
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• pp.573-582
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• 2008

We report a newly found natural habitat of Abeliophyllum distichum in mountainous slope range of Yeongdong-gun, Chungbuk Province. Abeliophyllum distichum Nakai is one of the Korean monotypic endemic species. Natural growth habitats of this species have been recorded from seven sites up to now, and all of the natural habitats are located in middle (Chungbuk Prov.) and middle west (Jeonbuk Prov.) parts of South Korea. Among the previously recorded seven natural habitats, six sites have been designated as Korean national monuments and protected with in situ conservation. New natural habitat of A. distichum is located on northwest slope of stiff hillock area beside the small stream, Seolgye-ri, Yeongdong-eup, Yeongdong-gun, Chungbuk Province. Total growing area is nearly $3,000 m^2$. It is 10-25 cm in soil depth and pH 5.0-6.5 in soil acidity in that area. And many of A. distichum are clustered with 2-5 individuals extended by stoloniferous asexual reproduction. And the total numbers of A. distichum are about 700 individuals with only typical white flowers, and the ratio between pin type and thrum type is 37% and 63%, respectively. The huge population of A. distichum is growing with Quercus mongolica-Fraxinus rhynchophylla association in a mixed forest, and it shows high affinity with Stephanandra incisa, Ligustrum obtusifolium, Euonymus alatus for. ciliatodentatus, and Smilax sieboldi.

• Journal of Digital Convergence
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• 제15권2호
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• pp.475-483
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• 2017

Based on the operating system of the advanced school athletic clubs operated to attempt a new paradigm of athletic culture in the field of school athletics, this study aimed to conduct an in-depth analysis of the student athletes' academic level and seek a solution for the stream of the times and integrated change based on a relative minimum academic achievement standard applied by this system. For Analyzing the difference in academic grades between subjects to which the minimum academic achievement standard by the event is applied, one-way ANOVA and MANOVA were used. First, the grade point average (GPA) of the student athletes by the event did not reach the GPA of most general students. Second, it was predicted that in applying a standard, relative to the general students, as academic grades increased, the probability in which the student athletes do not reach the minimum academic achievement standard would increase. Third, it turned out that, even in the phased application of the current minimum academic achievement standard to the GPA of the student athletes by the event, the ratio of the attainment of the minimum academic achievement was similar.