• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.444-451
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• 2020

This study was conducted to develop the hydraulic brake assembly for MUAV(Medium-altitude Unmanned Aerial Vehicle). The brake assembly has the self-gap adjuster which performs to maintain a constant gap between the piston and the disk, even if the friction pad wore down. The function of adjuster helps to keep the brake-reaction speed constant and prevent the unnecessary abrasion of the wear pad during the life of the brake assembly. The development of the aircraft hydraulic brake assembly with the self-gap-adjuster in this paper is the first ever in South Korea. The concept of the mechanism was defined and the formula which is necessary to calculate the friction force was set up in the paper. The tester was invented for the functional test and the proper operation of the self-gap-adjuster was confirmed through the test. Dynamo tests and flight tests were also carried out to verify the braking performance of the brake assembly.

• IMMUNE NETWORK
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• v.19 no.1
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• pp.1.1-1.13
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• 2019

Systemic lupus erythematosus (SLE) is the prototypic systemic autoimmune disease characterized by production of autoantibodies to various nuclear antigens and overexpression of genes regulated by IFN-I called IFN signature. Genetic studies on SLE patients and mutational analyses of mouse models demonstrate crucial roles of nucleic acid (NA) sensors in development of SLE. Although NA sensors are involved in induction of antimicrobial immune responses by recognizing microbial NAs, recognition of self NAs by NA sensors induces production of autoantibodies to NAs in B cells and production of IFN-I in plasmacytoid dendritic cells. Among various NA sensors, the endosomal RNA sensor TLR7 plays an essential role in development of SLE at least in mouse models. CD72 is an inhibitory B cell co-receptor containing an immunoreceptor tyrosine-based inhibition motif (ITIM) in the cytoplasmic region and a C-type lectin like-domain (CTLD) in the extracellular region. CD72 is known to regulate development of SLE because CD72 polymorphisms associate with SLE in both human and mice and CD72^-/- mice develop relatively severe lupus-like disease. CD72 specifically recognizes the RNA-containing endogenous TLR7 ligand Sm/RNP by its extracellular CTLD, and inhibits B cell responses to Sm/RNP by ITIM-mediated signal inhibition. These findings indicate that CD72 inhibits development of SLE by suppressing TLR7-dependent B cell response to self NAs. CD72 is thus involved in discrimination of self-NAs from microbial NAs by specifically suppressing autoimmune responses to self-NAs.

• Journal of Agricultural Extension & Community Development
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• v.1 no.1
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• pp.15-28
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• 1994

The ideas of Agricultural Copperatives as self-organization are to facilitate its life and development and to improve economic and social status. Its works are to improve agricultural productivity to have extension through self-help, self-reliance, cooperative. The purpose of this study presents direction of agricultural extension after U.R.

• Journal of Families and Better Life
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• v.10 no.1 s.19
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• pp.15-25
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• 1992

This article introduces the conceptual framework of self-efficacy and reviewes recent research articles which are related to development of self-efficacy in children. Self-efficacy means personal judgement about one's capability to organize his behavior in a specific situation. Perceived efficacy can have diverse effects on behavior, thought patterns and affective arousal. People acquire their efficacy information from their performance accomplishments, vicarious experiences, verbal persuasion and their physiological states. In this paper, I argue that two factors, psychological and environmental factor, contribute to the development of children's self-efficacy. Specifically reward, attributional feedback, social comparision and goal setting are classified to psychological factor and home environment, school environment and social environment belong to environmental factor. Since not many studies have been done in this area, in this paper I also suggest some directions for future research.

• International Journal of Computer Science & Network Security
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• v.21 no.12spc
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• pp.415-426
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• 2021

The implementation of iris biometrics on smartphone devices has recently become an emerging research topic. As the use of iris biometrics on smartphone devices becomes more widely adopted, it is to be expected that there will be similar efforts in the research community to beat the biometric by exploring new spoofing methods and this will drive a corresponding requirement for new liveness detection methods. In this paper we addresses the problem of presentation attacks (Spoofing) against the Iris Recognition System on mobile devices and propose novel Presentation Attack Detection (PAD) method which suitable for mobile environment.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.2
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• pp.297-308
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• 2008

This study developed career education program applying cooperative learning structures (Kagan, 1993, 1995, 1997), and tested its effect on elementary school children's career development. Sixth grade students of 2 classes were divided into experimental and control group, and 14 sessions of the program were applied to the experimental group for 8 weeks. Career development test(Lee, 2005) were performed before and after the program. Students in both groups were retested 3 months after the post-test to test continuing effects of the program. Score tendencies and their differences between experimental group and control group of children in 3 career development areas - self-awareness, educational and occupational exploration, and career planing - were tested and the results are as follows: development of 3 areas of self-awareness, educational and occupational exploration, and career planing were consistently increasing along the experimental sequence in experimental group, while the development of 3 areas showed no changes or declining tendencies in control group. Self-awareness and educational and occupational exploration did not show the statistically significant differences between the groups. Meanwhile, the career plaining showed statistically significant difference between the groups in post-test, meaning that the career education program with cooperative structure has positive effects on the career planing in 6th grade students.

• Clinical and Experimental Pediatrics
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• v.50 no.12
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• pp.1165-1172
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• 2007

Self/non-self discrimination and unresponsiveness to self is the fundamental properties of the immune system. Self-tolerance is a state in which the individual is incapable of developing an immune response to an individual's own antigens and it underlies the ability to remain tolerant of individual's own tissue components. Several mechanisms have been postulated to explain the tolerant state. They can be broadly classified into two groups: central tolerance and peripheral tolerance. Several mechanisms exist, some of which are shared between T cells and B cells. In central tolerance, the recognition of self-antigen by lymphocytes in bone marrow or thymus during development is required, resulting in receptor editing (revision), clonal deletion, anergy or generation of regulatory T cells. Not all self-reactive B or T cells are centrally purged from the repertoire. Additional mechanisms of peripheral tolerance are required, such as anergy, suppression, deletion or clonal ignorance. Tolerance is antigen specific. Generating and maintaining the self-tolerance for T cells and B cells are complex. Failure of self-tolerance results in immune responses against self-antigens. Such reactions are called autoimmunity and may give rise to autoimmune diseases. Development of autoimmune disease is affected by properties of the genes of the individual and the environment, both infectious and non-infectious. The host's genes affect its susceptibility to autoimmunity and the environmental factors promote the activation of self-reactive lymphocytes, developing the autoimmunity. The changes in participating antigens (epitope spreading), cells, cytokines or other inflammatory mediators contribute to the progress from initial activation to a chronic state of autoimmune diseases.

• Journal of Families and Better Life
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• v.28 no.3
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• pp.139-150
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• 2010

The main purpose of this study was to examine pathways from maternal parenting behavior to externalizing problem behavior through deviant peer affiliation and self-concept. A sample of 405 high school students (184 boys and 221girls) in the Gyeonggi-do region of South Korea completed questionnaires focusing on maternal monitoring and adolescent deviant peer affiliation, self-concept, and externalizing problem behavior. Data were analyzed by structural equation modeling. The results demonstrated that maternal monitoring indirectly influences adolescent externalizing problem behavior through deviant peer affiliation and/or self-concept. When maternal monitoring was perceived as low by adolescents, they were more involved with deviant peers. This was followed by a more negative self-concept. Finally, negative self-concept resulted in more externalizing problem behavior by adolescents. The results emphasize that deviant peer affiliation plays a crucial role in increasing adolescent externalizing problem behavior.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.246-248
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• 2017

Self-driving cars have three main functions. The first recognizes the surrounding environment, judge the risk, and lastly plans the drive path. Therefore, the driving operation is minimized. And it refers to a human friendly car capable of safe driving on its own. The reason for the need for self-driving car was to reduce traffic jams on limited roads and to reduce carbon dioxide emissions. Driving ahead of these self-driving car businesses can be expected to attract and expand the existing business and expand the new business and create new business opportunities for ICT firms. It is urgent for the concerned agencies to establish legal and institutional basis for self-driving cars. By doing so, new services could be provided to consumers. Therefore, this paper introduces the technological development trends for self-driving cars.

• Journal of the Korea Society of Computer and Information
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• v.27 no.5
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• pp.205-213
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• 2022

This study is to analyze the relationship among potential variables of self-development, social development, learning readiness, and academic ability using data from the Panel Study on Korean Children, which was surveyed in 2014, and to find factors affecting the academic ability of preschool children will be. The subjects of this study were 6-year-old children of 1113 households among 2150 households in the 7th Panel Study on Korean Children(2014) data, excluding non-responders and system-missing 1037 households. As a result of analyzing the path effect of the research model, it was found that, between self-development and academic skills, self-development had a direct effect on academic skills and also had a significant indirect effect through social development and learning readiness as a medium. In addition, it was found that learning readiness had the greatest influence among self-development, social development, and learning readiness on academic skills. As a result, the academic skills of preschool-age children should be treated with great importance in order to develop them into talents with creativity and problem-solving ability.