• Title/Summary/Keyword: internal stability

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A Study on Necessity and Possibility of Specialized Research Institute for Local Education Autonomy (지방교육자치 전문연구기관의 설립 필요성과 가능성 탐색)

  • Rah, MinJoo;Park, Soo-Jung;Ha, BongWoon;Cha, JiCheol
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.141-150
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    • 2019
  • The purpose of this study is to explore the necessity and possibility of establishing a research institute for local educational autonomy where the importance and necessity of institution establishment and operation are increasing with the decentralization and educational autonomy. The necessity of establishing a local educational autonomous research institute was examined in terms of both external and internal necessities, and the possibility of establishment in terms of the form of establishment, financial resources, and legal basis. In order to effectively cope with common issues by leading the nation's educational autonomy policy and legal agenda, and to support regional policy research and development by linking and cooperating with regional educational policy research institutes, local educational autonomous research institutes are established. This is an urgent point. Considering the publicity, professionalism, economic feasibility, and stability of specialized research institutes, the form of foundation corporation seems to be appropriate, and, like the case of specialized research institutes in general local autonomy, legal grounds for the establishment of special law should be prepared. In the future, it is necessary to conduct collaborative discussions and academic discussions with the Ministry of Education and the National Council for Superintendents of Education.

A COMPARATIVE STUDY OF THE 1-PIECE AND 2-PIECE CONICAL ABUTMENT JOINT: THE STRENGTH AND THE FATIGUE RESISTANCE

  • Kwon, Taek-Ka;Yang, Jae-Ho;Kim, Sung-Hun;Han, Jung-Suk;Lee, Jai-Bong
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.6
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    • pp.780-786
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    • 2007
  • Statement of problem. The performance and maintenance of implant-supported prostheses are primarily dependent upon load transmission both at the bone-to-implant interface and within the implant-abutment-prosthesis complex. The design of the interface between components has been shown to have a profound influence on the stability of screw joints. Purpose. The Purpose of this study was to compare the strength and the fatigue resistance of 1-piece and 2-piece abutment connected to oral implant, utilizing an internal conical interface. Material and methods. Twenty $Implatium^{(R)}$ tapered implants were embedded to the top of the fixture in acrylic resin blocks. Ten $Combi^{(R)}$(1-piece) and $Dual^{(R)}$(2-piece) abutments of the same dimension were assembled to the implant, respectively. The assembled units were mounted in a testing machine. A load was applied perpendicular to the long axis of the assemblies and the loading points was at the distance of 7mm from the block surface. Half of 1-piece and 2-piece abutment-implant units were tested for the evaluation of the bending strength, and the others were cyclically loaded for the evaluation of the fatigue resistance until plastic deformation occurred. Nonparametric statistical analysis was performed for the results. Results. Mean plastic and maximum bending moment were $1,900{\pm}18Nmm,\;3,609{\pm}106Nmm$ for the 1-piece abutment, and $1,250{\pm}31Nmm,\;2,688{\pm}166Nmm$ for the 2-piece abutment, respectively. Mean cycles and standard deviation when implant-abutment joint showed a first plastic deformation were $238,610{\pm}44,891$. cycles for the 1-piece abutment and $9,476{\pm}3,541$ cycles for the 2-piece abutment. A 1-piece abutment showed significantly higher value than a 2-piece abutment in the first plastic bending moment (p<.05), maximum bending moment (p<.05) and fatigue strength (p<.05). Conclusion. Both 1-piece and 2-piece conical abutment had high strength and fatigue resistance and this suggests long-term durability without mechanical complication. However, the 1-piece conical abutment was more stable than the 2-piece conical abutment in the strength and the fatigue resistance.

A Case Study on the Reinforcement of Existing Damaged Geogrid Reinforced Soil Wall Using Numerical Analyses (수치해석을 이용한 기존 피해 보강토 옹벽의 보강에 관한 사례 연구)

  • Won, Myoung-Soo;Langcuyan, Christine P.;Choi, Jeong-Ho;Ha, Yang-Seong
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.1
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    • pp.75-82
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    • 2020
  • There have been often cases of collapse for geogrid reinforced soil (GRS) retaining wall. Hence, social interest in the reinforcement and restoration of the collapsed GRS wall is increasing day by day. However, there are only few researches. For this reason, a series of numerical analyses using the Plaxis 2D program was conducted in this study to analyze the suitable reinforcement methods that can be applied on the existing damaged GRS wall caused by overturning of the modular blocks facing and the surface settlement at the backfill as the results from the design failure. The restoration plan used in this study is composed of two cases: (Case 1) soil nailing reinforcement and reinforced concrete (RC) wall facing construction on the existing damaged GRS wall; and (Case 2) removal of the entire damaged GRS wall and then reconstruction. The results on the internal stability of the GRS wall show that Case 1 obtained a greater safety factor than Case 2 for tensile force while Case 2 had a greater safety factor than Case 1 for pullout failures. Case 1 was found to be more stable than Case 2 in terms of the global slope safety by shear strength reduction method and the external deformation behavior by numerical analysis. In this study, the existing damaged GRS wall which was reinforced using Case 1 method shows more stable external behavior.

Thermal Analysis of Vegetable Insulation Oil for Hermetically Sealed Wind Turbine Transformer (풍력발전기용 밀폐형 변압기의 식물성 절연유에 대한 열적특성 연구)

  • Lee, Sung-Won;Lee, Joon-Yeob;Kim, Jun-Su;Woo, Jae-Hi;Kim, Dong-Hae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.1
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    • pp.97-102
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    • 2012
  • A hermetically sealed oil transformer is designed by applying expanding function of the tank due to the volume changes of the insulation oil according to the temperature rises. When the insulation oil expands, an increase in the volume of the corrugated fin prevents a pressure rise of the transformer. For a wind turbine transformer, a vegetable-oil-immersed transformer has the advantages of excellent biodegradation and fire-resistant properties like an exceptionally high fire point. When vegetable oil is substituted for mineral oil, however, the maximum winding temperature rises because of the decrease in the internal circulation flow rate resulting from the variations of the oil's physical characteristics, such as density and viscosity. The purpose of this study is to develop a hermetically sealed vegetable oil transformer that can be applied in a wind turbine and to analyze the thermal stability of the active part of the transformer to deal with pressure variations due to the temperature changes. In addition, thermal tests for the vegetable oil transformer have been performed, and the measured values are compared with the analysis results.

Rheological Changes of Dough and Breadmaking Qualities of Wheat Flour with Additions of Soy Flour (대두혼합식빵 제조시 대두첨가량에 따른 반죽과 식빵의 물성 변화)

  • 김인호;하상철;이인구
    • Food Science and Preservation
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    • v.9 no.4
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    • pp.418-424
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    • 2002
  • This study was undertaken to develop the optimum baking formular and process in making the improved soy-wheat composite breads furtified with soy flour, which has been known for a source of biologically active phytochemicals and for more vegetable proteins as well. The effects of the addition of soy flour on a rheological properties of dough, on the sensory characteristics of breads, and on the possibilities of commercialization of these functional breads were investigated. As the added amount of soy flour increased, water absorption, development time and the weakness value of dough were increased, but dough stability were decreased in the farinograph. In the extensograph, the more soy flour was added, the less the extensibility and the resistance to extention were shown. As the amount of soy flour increased, gelatinazation point was increased in the amylograph, but the maxium viscosity was decreased. As the added amount of soy flour was increased, b value(yellowness) was obviously increased, L value(lightness) was slightly decreased. However, a value(redness) was not nearly changed in the color of cut loaves. In sensory evaluation, the more soy flour was added, the less the external, the internal characteristics and the eating qualities were shown. Accorting to the addition of soy flour, the toughness and the brittleness tended to be increased proportionally. The dough of 10% soy-wheat composite flour(SF10) was the most favorable on the baking performance.

A Literary Review of Human Being by Nursing Aspects - As the Theory Development in Nursing - (인간에 대한 간호학적인 해석에 관한 고찰 -간호이론발달을 통해서 -)

  • 이광자
    • Journal of Korean Academy of Nursing
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    • v.9 no.2
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    • pp.49-61
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    • 1979
  • A review of this literature and discussions reveal a development of ideas concerning the elements of nursing models. The elements of a nursing model are the nurses view of the human being, nursing's goal, and nursing activities. It has long been recognized that human beings, at one time or another, require nursing care. Varieties of literature were reviewed in regard to the human being as recipient of nursing care through the theory development in nursing. Florence Nightingale initiated the modern era of nursing and described more clearly man as the recipient of nursing care. She looked at man as responding to the laws of nature whether the person was healthy or sick. Henderson added to Nightingale's concept of man , the recipient of nursing care by emphasizing that man is a whole, complete, and independent being. Her view is further specified by her enumeration of the activities the human being must perform. Johnson has developed a very comprehensive view of man as the recipient of nursing care. Man is a behavioral system which has a tendency to achieve and maintain stability in patterns of functioning. Like Nightingale, Johnson sees that similar patterns occur in both health and illness. Johnson postulates that the whole behavioral system of the human is composed of eight sub-systems: affiliative, achievement, aggressive, dependency, eliminative, ingestive, restorative, sexual. Roger's main contribution to the development of nursing models was her emphasis upon unitary man. She pointed out that man is a unified whole, possessing his own integrity and manifesting characteristics that“are more than and different from the sum of his parts.”Rogers focuses on the life processes of the human and points out that these processes have the following characteristics. Wholeness, openness, unidirectionality, pattern and organization, sentence, and thought. According to Roy, man is a biopsychosocial being in constant interaction with a changing environment. To cope with this changing environment, man has certain innate and acquired mechanisms. Man's ability to respond positively or to adapt, depends upon the degree of the change taking place and the state of the person coping with the change. When she analyzes man as an adaptive organism she further describes man as being composed of four adaptive modes: physiological needs, self-concept, role function, and interdependence. Based on the literary review through the theory development in nursing, general approach by a unified nursing model to a view of the recipient of nursing care may be stated as follows: Man is a unified whole composed of subsystems with a flexible and normal line of defense; his internal regulating mechanisms help him to cope with a changing environment; he functions by the principles of homeodynamics.

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Antimicrobial Active Substances from Entomopathogenic Fungi (Various Applications of Entomopathogenic Fungi)

  • Shin, Tae Young;Woo, Soo Dong;Kim, Jeong Jun
    • 한국균학회소식:학술대회논문집
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    • 2016.05a
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    • pp.13-13
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    • 2016
  • Insects constitute the largest and most diverse group of animals in the world. They also serve as the hosts or nutrient sources for an immense assemblage of pathogens, parasites, and predators. More than 700 fungal species from 100 genera have adopted an entomopathogenic lifestyle. Although entomopathogenic fungi were studied as only biocontrol agents against a variety of pests in various countries, it has been recently focused their additional roles in nature. They are antagonists to/against plant pathogens, endophytes, and possibly even plant growth promoting agents. The potential antimicrobial effect against fungal plant pathogens by an isolate of entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have been reported since late 1990s, but wasn't reported pathogenicity of the isolate against pests. Later, a Canadian Lecanicillium sp. isolate and L. longisporium isolated from Vertalec$^{(R)}$ showed simultaneous control effect against both aphid and cucumber powder mildew. Therefore, the antimicrobial activities of 342 fungi isolates collected from various regions and conditions in Korea were evaluated against plant pathogenic fungus Botrytis cinerea using dual culture technique on agar plate. As a result, 186 isolates (54.4%) shown the antifungal activity against B. cinerea. The culture filtrates of selected fungi completely suppressed the growth of the microorganisms, indicating that suppression was due to the presence of antimicrobial substances in the culture filtrate. Mode of action of these fungi against insect involves the attachment of conidia to the insect cuticle, followed by germination, cuticle penetration, and internal dissemination throughout the insect. During infection process, secreted enzymes, proteinous toxins, and/or secondary metabolites secreted by entomopathogenic fungi can be used to overcome the host immune system, modify host behavior, and defend host resources. Recently, secondary metabolites isolated from entomopathogenic fungi have been reported as potential bioactive substances. Generally, most of bioactive substances produced by entomopathogenic fungi have reported low molecular weight (lower than 1,000 g/mol) as peptide and, in contrast the high molecular weight fungal bioactive substances are rare. Most substances based on entomopathogenic fungi were shown antimicrobial activity with narrow control ranges. In our study we analyzed the antimicrobial substances having antagonistic effects to B. cinerea. Antimicrobial substances in our fungal culture filtrates showed high thermostability, high stability to proteolytic enzymes, and hydrophilicity and their molecular weights were differed from substance. In conclusion, entomopathogenic fungi showed pathogenicity against insect pests and culture filtrate of the fungi also shown to antimicrobial activity. In the future, we can use the entomopathogenic fungi and its secondary metabolites to control both insect pest control and plant pathogenic fungi simultaneously.

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Development of the Self-Report Wisdom Scale for the Elementary Gifted Students (초등 영재아동을 위한 자기보고식 '지혜' 척도 개발)

  • Jun, Byung-Ok;Han, Ki-Soon
    • Journal of Gifted/Talented Education
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    • v.22 no.2
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    • pp.427-450
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    • 2012
  • This study was intended to develop a self-report wisdom scale for the elementary gifted students. For this, related literature was reviewed in depth and open ended questionnaire about the wisdom qualities was conducted. Based on these, a self-report wisdom scale, which was comprised of 42 items in 4 factors such as the situation judgment and problem-solving ability, the communication ability and skills, the emotional stability, the insight and adaptation, was developed. For this preliminary scale, 215 elementary gifted students were surveyed. And for the confirmatory factor analysis, 256 elementary gifted students participated. The results of the study were as follows. The fit of measurement model was found to be ${\chi}^2$=1596.46 (df=813, p=.00), TLI .90, CFI .91, RMSEA .046, indicating most of fit indexes were acceptable. The reliability for each of 42-item by the sub-factors also appeared to be good, showing that internal consistency reliability by the configuration factors was 0.86, .87, .89, .87 each relatively. In addition, to verify the validity of the wisdom scale, the convergent and discriminate validities were obtained through the correlation analysis among the psychological characteristics which were considered to be related to the wisdom. Finally, practical implications of the study were discussed in depth.

Unsaturated Shear Strength Characteristics of Nakdong River Silty Sand (낙동강 실트질 모래의 불포화 전단강도 특성)

  • Jin, Guang-Ri;Shin, Ji-Seop;Park, Sung-Sik;Kim, Ki-Young
    • Journal of the Korean Geotechnical Society
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    • v.29 no.2
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    • pp.47-56
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    • 2013
  • There are many technical problems, which can not be resolved by the concept of saturated soil mechanics. Unsaturated soils show an apparent cohesion due to negative pore pressure and relatively lower permeability due to entrapped air compared to saturated soils. The determination of engineering properties of soils with various moisture content is very important to evaluate shear strength and stability of natural and engineered soils. So various researches should be made on unsaturated soils. Especially, sandy soils are widely distributed near Nakdong river, one of the four rivers where Restoration Projects were carried out. Many structures such as dams, flood control facilities, detention facilities and reservoirs have been built in this area. In this study, unsaturated triaxial compressive tests were conducted on sands or silty sands at Nakdong river in order to provide their fundamental characteristics for design and construction of geotechnical structures. As a result of the tests, the maximum deviator stress increased as the confining stress and matric suction increased. The cohesion increased non-linearly as the matric suction increased, but the angle of internal friction was marginally changed.

A Study on Intensifying Efficiency of Presidential Security Service Organization through the Analysis of Press Media (언론매체 분석을 통한 대통령경호조직의 효율성 제고에 관한 연구)

  • Kim, Il Gon;Ahn, Young Kyu
    • Convergence Security Journal
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    • v.14 no.1
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    • pp.23-32
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    • 2014
  • Quantitative rise and This study carried out qualitative research by utilizing NVivo 10 focusing on the contents of mass media such as newspaper or internet on the presidential security service up to the Park Geun-hye government from the 3rd Republic of Korea, which was established the presidential security service. The aim is to present opinion so that the presidential security organization can strengthen capability and function within the governmental organization down the road based on the contents of categories, which were elicited through this. First, there is a need of solidifying the internal stability with the expansion in the activity sphere of organization and of externally approaching the public with removing sense of difference caused by offering personal protection only to some of the privileged class in the meantime. Second, it is the foundation of a reason related to crime in a cause for Discharge by Authority pertinent to "law on security for president and others" in Article 10 in order to prevent a criminal act of having abused the task characteristic and the position superiority or an external pressure act related to intervention in rights. Third, there is a need of making it recognized as very important organization with putting differentiation from other organizations of the government by providing the disciplinary level more strictly than "disciplinary order on public officials" based on particularity and importance dubbed presidential security service along with correspondingly applying "disciplinary order on public officials" in Article 31 in accordance with "enforcement ordinance of law on security for president and others" in terms of service negligence and false-information report in relation to task performance.