• Journal of the Economic Geographical Society of Korea
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• v.25 no.4
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• pp.499-513
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• 2022

This study targets the rechargeable battery industry, which has been rapidly growing recently. The rechargeable battery industry is closely related to the electric vehicle industry. However, other factors also influence it. Currently, rechargeable battery companies show a pattern of restructuring production space by various means. To determine the causes of these production spaces, the factors affecting regional and national scales were thoroughly examined. As a result, the location factors for rechargeable battery-related companies are determined by cooperative relationships with assembled car companies, government policy regulations, and the stability of supply of key materials. And a spatial strategy was implemented to make the most of these circumstances.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.6
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• pp.74-85
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• 2022

Since the late 1990s, the demand for developing green or reduced-toxic storable propellants has been rising to replace the existing toxic propellants. Most of the research activities are focusing on development of new hypergolic fuels and either white fuming nitric acid or hydrogen peroxide is utilized as an oxidizer. The newly-developed hypergolic fuels are classified as three types, catalytic fuel, reactive fuel, and ionic fuel. In the present study, recent R&D trend of ionic liquid propellants is described and the main results in the previous studies are analyzed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.997-1005
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• 2013

Since the cross-sectional shape of the Nakdong river is compound type, the water stage rises up to the top of the flood plane, as the flow discharge increases during the extreme rain storm in summer. The recent increase of rainfall intensity and flood frequency results in the immersions of parks and hydrophilic facilities located in the flood plain. Therefore it is necessary to analyze the hydraulic characteristics evolved by the extreme rain storm in the flood plain. The study reach ranging from the Gangjeong Goryeong Weir and the Dalseong Weir, where several hydraulic facilities are located along the channel, was selected and numerical simulations were conducted for 42 hours including the peak flood of the typhoon Sanba. The 2-D transient model, FaSTMECH was employed and the accuracy of the model was assessed by comparing the water level between the simulation results and the measured ones at a gauging station. It showed a high correlation with $R^2$ of 0.990, AME of 0.195, and RMSE of 0.252. In addition, the inundation time, the inundation depth, the inundation velocity, and the shear stress variation in the flood plain facilities were analyzed.

• Journal of Korea Technology Innovation Society
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• v.17 no.3
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• pp.563-583
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• 2014

We classified collaboration types of Government-supported Research Institutes (GRIs) in Korea to make a creation knowledge with the openness and the diversity. The openness is described to collaboration dependence and leading intensity, and the diversity is expressed to collaboration diversity and collaboration concentration. We suggest four taxonomy models explained in terms of the openness and the diversity with country level and institute level. This study uses 39,507 papers in SCOUPS DB that include author(s) affiliated to 26 GRIs. It concludes that many GRIs is classified to the type of multilateral collaboration follower in institute level and to the type of global network player in country level from the perspective of openness. In the aspect of diversity, many GRIs is concentrated to the collaboration type of picky eater or monophagous in institute level and to the multinatioal asymmetry type or non-multinational asymmetry type in country level. It is necessary for GRIs to lead collaboration and to transfer inhouse R&D institutes with high performance to be competitive institutes which make high quality knowledge.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.197-210
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• 2022

Entomopathogenic fungi can be used to control a variety of sucking and chewing insects, with little effect on beneficial insects and natural enemies. Approximately 170 entomopathogenic fungal insecticides have been registered and used worldwide, with the recent focus being on the mode of action and mechanism of insect-fungal interactions. During the initial period of research and development, the industrialization of entomopathogenic fungi focused on the selection of strains with high virulence. However, improvement in productivity, including securing resistance to environmental stressors, is a major issue that needs to be solved. Although conidia are the primary application propagules, efforts are being made to overcome the limitations of blastospores to improve the economic feasibility of the production procedure. Fungal transformation is also being conducted to enhance insecticidal activity, and molecular biology is being used to investigate functions of various genes. In the fungi-based pest management market, global companies are setting up cooperative platforms with specialized biological companies in the form of M&As or partnerships with the aim of implementing a tank-mix strategy by combining chemical pesticides and entomopathogenic fungi. In this regard, understanding insect ecology in the field helps in providing more effective fungal applications in pest management, which can be used complementary to chemicals. In the future, when fungal applications are combined with digital farming technology, above-ground applications to control leaf-dwelling pests will be more effective. Therefore, for practical industrialization, it is necessary to secure clear research data on intellectual property rights.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3486-3491
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• 2012

The purpose of this study was to examine the variables of success in the national dental hygienist licence examination at D college. The subjects in this study were 120 dental hygiene juniors at D college located in Gangwon Province. The collected data were analyzed by the statistical package SPSS WIN 13.0 and a R2.13.2 program, and $x^2$(Chi-square) test, regression analysis, multiple linear regression analysis and logistic regression analysis were utilized. The findings of the study were as follows: 1. There was a tendency that the pass rate was higher among the students who were more satisfied with their major, whose academic standing was higher and who scored higher in trial examinations. 2. There was a positive correlation between academic standing and trial exam scores. 3. When their academic standing and satisfaction level with major were the same, an increase of one point in trial exams led to a 1.141-fold rise in the probability of passing the national exam. In this study, trial exam scores were identified as the variable to exert the largest influence on success in the national dental hygienist qualification exam. Therefore more intensive guidance should be provided for students who make a preparation for the national exam yet score low in trial exams.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.704-712
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• 2008

Purpose : A prospective, controlled trial was conducted to evaluate growth, efficacy, safety and nutritional status for very low birth weight infants fed with human milk fortified with Maeil human milk fortifier (Maeil $HMF^{(R)}$; Maeil Dairies Co., Ltd.). Methods : We enrolled 45 premature infants with a birth weight <1,500 g and gestational age <33 weeks, who were born at Dong-A University Hospital from October, 2006 through December, 2007. They were divided into 2 groups: infants in one group were fed with human milk fortified with $HMF^{(R)}$, and the second were fed with preterm formula. Growth, biochemical indices, feeding tolerance, and other adverse events in each group were assessed serially and compared relatively. Follow-up data were also collected after discharge at 1, 3, and 6 months corrected age. Results : Characteristics of the 2 groups including average gestational age, birth weight, sex, respiratory distress syndrome, patent ductus arteriosus, and other adverse events (sepsis, retinopathy of prematurity, and intraventricular hemorrhage) showed no significant difference. Average feeding start day ($8.00{\pm}3.27d$ vs. $8.86{\pm}5.37d$) (P=0.99) and the number of days required to reach full feeding after start feeding ($41.78{\pm}20.47d$ vs $36.86{\pm}20.63d$) (P=0.55) were not significantly different in the group fed human milk fortified with $HMF^{(R)}$ when compared with the group that was fed preterm formula. The duration of total parenteral nutrition and the incidence of feeding intolerance also showed no differences between the 2 groups. Although infants fed with human milk fortified with $HMF^{(R)}$ showed faster weight gain than those fed with preterm formula at the end stage of the admission period, other growth indices of the two groups showed no significant difference. No significant correlations were found between the 2 groups with regard to weight gain velocity, height gain velocity, head circumference velocity, and post-discharge follow up growth indices. Conclusion : Premature infants fed human milk fortified with $HMF^{(R)}$ showed no significant difference compared with those fed preterm formula in growth, biochemical indices, and adverse events. Using human milk fortifier can be an alternative choice for very low birth weight infants, who need high levels nutritional support even after discharge from NICU.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.408-417
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• 2016

The frequent regional torrential or heavy rain and typhoon mostly caused by climate change has resulted in sediment disasters particularly in mountainous or hilly areas. More than 65% of South Korea is mountainous and development and rapid urbanization has brought lots of steep sloping industrial complexes, which are adjacent to cities. Such continuous urbanization and industrialization can result in an increase in serious damage to those places. Korea has very high population density so sediment disaster could result in a tremendous loss of property and life. A recent 10-year (2001~2010) study of the average annual loss shows 68 casualties and property loss of 1.7044 trillion Won(?), which indicates a 20% and 25% decrease for both life and property, respectively, but urban areas are experiencing increasing damage. In this paper, a comprehensive simulator composed by references, analyses, and the recent technologies was applied to visualize the scale of the damaged Woomyeon-san (Mt.) and verify the performance of the simulator.

• Journal of Korea Technology Innovation Society
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• v.21 no.2
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• pp.636-662
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• 2018

Recently, the Moon administration established the Ministry of Small and Medium-sized Enterprises (SMEs) and Startups, as part of its national strategy for start-up and innovation growth led by small and medium-sized venture companies. In a slowing economy, as venture companies with excellent internal competencies are seen to be favorable to growth, the government funding for technology development is becoming increasingly important. Previous studies examine the internal competence factors that can strengthen competitiveness through self-efforts and the influence structure of growth stage, which is an important factor in industrial environment, on business performance. As the government support for venture firms has been strengthened, the effect of government funding on the management performance and technological innovation performance of venture firms have been recently discussed in various ways. However, there is a lack of precedent research on the moderating effect of the utilization of government funding on the existing influence structure in which firm's internal competence and growth stages affects business performance. Therefore, this study examined whether the internal competencies of the venture firms and the stage of growth have direct effects on business performance and analyzed the moderating effect in connection with government funding utilization under these influence structures. The results of the study are as follows. First, the utilization of government funding in the venture firms whose R&D personnel ratio is relatively low, not to have own brands and showed an increase of employees has a significantly positive influence on business performance. Second, the moderating effects of the government funding utilization at the high growth stage of the venture firms are shown significantly. These results suggest that the venture policy linked to the job creation of the present government requires not only the support considering R&D personnel but also the necessity of supporting human resources policy to a greater extent and further study on the effectiveness of venture firms in the high growth stage.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.424-434
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• 2009

Statement of problem: Problems such as loosening and fractures of retained screws and fracture of implant fixture have been frequently reported in implant prosthesis. Purpose: Implant has weak mechanical properties against lateral loading compared to vertical occlusal loading, and therefore, stress analysis of implant fixture depending on its material and geometric features is needed. Material and methods: Total 28 of external hexed implants were divided into 7 of 4 groups; Group A (3i, FULL $OSSEOTITE^{(R)}$Implant), Group B (Nobelbiocare, $Br{\aa}nemark$ $System^{(R)}$Mk III Groovy RP), Group C (Neobiotec, $SinusQuick^{TM}$ EB), Group D (Osstem, US-II). The type III gold alloy prostheses were fabricated using adequate UCLA gold abutments. Fixture, abutment screw, and abutment were connected and cross-sectioned vertically. Hardness test was conducted using MXT-$\alpha$. For fatigue fracture test, with MTS 810, the specimens were loaded to the extent of 60-600 N until fracture occurred. The fracture pattern of abutment screw and fixture was observed under scanning electron microscope. A comparative study of stress distribution and fracture area of abutment screw and fixture was carried out through finite element analysis Results: 1. In Vicker's hardness test of abutment screw, the highest value was measured in group A and lowest value was measured in group D. 2. In all implant groups, implant fixture fractures occurred mainly at the 3-4th fixture thread valley where tensile stress was concentrated. When the fatigue life was compared, significant difference was found between the group A, B, C and D (P<.05). 3. The fracture patterns of group B and group D showed complex failure type, a fracture behavior including transverse and longitudinal failure patterns in both fixture and abutment screw. In Group A and C, however, the transverse failure of fixture was only observed. 4. The finite element analysis infers that a fatigue crack started at the fixture surface. Conclusion: The maximum tensile stress was found in the implant fixture at the level of cortical bone. The fatigue fracture occurred when the dead space of implant fixture coincides with jig surface where the maximum tensile stress was generated. To increase implant durability, prevention of surrounding bone resorption is important. However, if the bone resorption progresses to the level of dead space, the frequency of implant fracture would increase. Thus, proper management is needed.