• International Journal of Vascular Biomedical Engineering
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• 제3권2호
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• pp.1-9
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• 2005

Flow-induced dilation of blood vessel is the result of a series of bioreaction in vascular endothelial cells(VEC). Shear stress change by blood flow in human artery or vein is sensed by the mechanoreceptor and responsible for such a chain reaction. The inositol(1,4,5)-triphophate($IP_3$) is produced in the first stage to elevate permeability of the intercellular membrane to calcium ions by which the cytosolic calcium concentration is consequently increased. This intracellular calcium transient triggers synthesis of EDRF and prostacyclin. The mathematical model of this VEC calcium dynamics is reproduced from the literature. We then use the Computational Fluid Dynamics(CFD) technique to investigate the blood stream dictating the VEC calcium dynamics. The pulsatile blood flow in a stenosed blood vessel is considered here as a part of study on thrombogenesis. We calculate the pulsating shear stress (thus its temporal change) distributed over the stenosed artery that is implemented to the VEC calcium dynamics model. It has been found that the pulsatile shear stress induces larger intracellular $Ca^{2+}$ transient plus much higher amount of EDRF and prostacyclin release in comparison with the steady shear stress case. It is concluded that pulsatility of the physiological shear stress is important to keep the vasodilation function in the stenosed part of the blood vessel.

• 과학기술학연구
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• 제8권1호
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• pp.55-95
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• 2008

본 연구는 2000년부터 2002까지 진행된 세포응용연구사업단 설립과정을 토대로 배아줄기세포 연구를 둘러싼 기대역학구조를 분석하고자 시도되었다. 기대역학은 기대구성-재원확보-연구의무이행-기대구성의 과정이 반복적으로 나타나면서 구조화된다. 일반적으로 연구자들은 해당 연구결과에 대해 매우 신중하고 중립적인 태도를 보인다. 하지만 일부 관련 연구자들의 경우 과도한 전망을 제시하며 기대구성에 적극적인 모습을 보이는데 이는 재원확보와 윤리적 논쟁방어를 위한 역학창출이라는 전략적 관점에서 이해될 수 있다. 거대규모의 재원과 인력이 소요되는 생명공학연구개발의 경우 기대역학창출은 연구개발의 성패에 결정적인 요인으로 작용하기 때문에 이러한 전략구사는 더욱 중요한 의미를 갖게 된다. (배아)줄기세포를 둘러싼 연결망을 '기대역학'이라는 개념틀을 이용해 분석하게 되면 국내 (배아)줄기세포 연구자의 정체성이 좀 더 분명하게 드러나게 되고 정책담당자나 대중의 의사결정과정에 도움이 될 만한 의미 있는 결론에 도달할 수 있다.

• IMMUNE NETWORK
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• 제13권2호
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• pp.55-62
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• 2013

Swiprosin-1 exhibits the highest expression in $CD8^+$ T cells and immature B cells and has been proposed to play a role in lymphocyte biology through actin remodeling. However, regulation of swiprosin-1 gene expression is poorly understood. Here we report that swiprosin-1 is up-regulated in T cells by PKC pathway. Targeted inhibition of the specific protein kinase C (PKC) isotypes by siRNA revealed that $PKC-{\theta}$ is involved in the expression of swiprosin-1 in the human T cells. In contrast, down-regulation of swiprosin-1 by A23187 or ionomycin suggests that calcium-signaling plays a negative role. Interestingly, swiprosin-1 expression is only reduced by treatment with $NF-{\kappa}B$ inhibitors but not by NF-AT inhibitor, suggesting that the $NF-{\kappa}B$ pathway is critical for regulation of swiprosin-1 expression. Collectively, these results suggest that swiprosin-1 is a $PKC-{\theta}$-inducible gene and that it may modulate the late phase of T cell activation after antigen challenge.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.146-153
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• 2007

A mathematical competition model between normal flora and an invading pathogen was devised to allow analysis of bacterial infections in a host. The normal flora includes the various microorganisms that live on or within the host and act as a primary human immune system. Despite the important role of the normal flora, no mathematical study has been undertaken on models of the interaction between it and invading pathogens against a background of antibiotic treatment. To quantify key elements of bacterial behavior in a host, pairs of nonlinear differential equations were used to describe three categories of human health conditions, namely, healthy, latent infection, and active infection. In addition, a cutoff value was proposed to represent the minimum population level required for survival. The recovery of normal flora after antibiotic treatment was also included in the simulation because of its relation to human health recovery. The significance of each simulation parameter for the bacterial growth model was investigated. The devised simulation showed that bacterial proliferation rate, carrying capacity, initial population levels, and competition intensity have a significant effect on bacterial behavior. Consequently, a model was established to describe competition between normal flora and an infiltrating pathogen. Unlike other population models, the recovery process described by the devised model can describe the human health recovery mechanism.

• Human Ecology Research
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• 제62권2호
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• pp.233-248
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• 2024

The purpose of this study was to describe the family life and relationships of national family center users in 2023. A sample of 1,086 adults was recruited from 48 family centers across South Korea. Participants, both online and offline, reported on various aspects of family life, including satisfaction, gender equality, work-home-life balance, family leisure, and internet usage for family and household purposes. Additionally, family relationships were explored in terms of dynamics with a spouse, children, and adult children. Data were analyzed using descriptive statistics and t-tests. In the family life domain, center users reported a high level of satisfaction, with women exhibiting greater awareness of gender equality and higher engagement in household chores than men. Furthermore, although a moderate balance among work, home, and life was reported, time emerged as a significant challenge for family leisure. Regarding technology, center users frequently utilized the internet for family communication, leisure, shopping, and household management. In the family relationships domain, men were more satisfied with spousal relationships than women. Center users reported high satisfaction with parent-child relationships. Parents of school-aged children perceived economic burdens, while those with adult children frequently provided psychological and instrumental support. These findings suggest the need for program modification and the development of new initiatives within national family centers to better support the diverse needs of families in terms of life satisfaction and relationship dynamics.

• Nuclear Engineering and Technology
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• 제43권4호
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• pp.375-382
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• 2011

The prospects for growth of the nuclear power industry in Korea have improved remarkably as the demand for energy increases in stride with economic development. Meanwhile, as nuclear energy development is enhanced, nuclear technology has also improved evolutionarily and innovatively in the areas of reactor design and safety measures. As nuclear technology development in Korea advances, more human resources are required. Accordingly, the need for a well-managed program of human resource development (HRD) aimed at assuring needed capacities, skills, and knowledge and maintaining valuable human resources through education and training in various nuclear-related fields has been recognized. A well-defined and object-oriented human resource development and management (HRD&M) is to be developed in order to balance between the dynamics of supply and demand of the workforce in the nuclear industry. The HRD&M schemes include a broad base of disciplines, education, sciences, and technologies within a framework of national sustainable development goals, which are generally considered to include economics, environment, and social concerns. In this study, the projection methodology considering a variety of economic, social, and environmental factors was developed. Using the developed methodology, medium- and long-term nuclear human resources projections up to 2030 were conducted in compliance with the national nuclear technology development programmes and plans.

• 한국멀티미디어학회논문지
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• 제13권12호
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• pp.1778-1785
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• 2010

This paper proposes a new video-based method of analyzing human gait which is a highly variable dynamic process. It captures a human gait of varying directions as a trajectory in the phase space. The proposed method includes two options of a stochastic process model and a self-organizing feature map as the tool of feature space representation and analysis. Test results show that the model is highly intuitive and we believe it can contribute to our understanding of human activity as well as gait behavior.

• 로봇학회논문지
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• 제2권4호
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• pp.341-345
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• 2007

This paper proposes an emotional interaction model between human and robot using an android. An android is a sort of humanoid robot that the outward shape of robot is almost the same as that of human. The android is a robot platform to implement and test emotional expressions and human interaction. In order to behave for the android like human, a structure of internal emotion system is very important. In our research, we propose a novel emotional model of android based on biological hormone and emotion space. Proposed emotion model has an advantage that it can represent emotion change as time by hormone dynamics.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.181.1-181
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• 2001

Human dummies are essential tools in the development of such sensible products as vehicles. Dummies are actively used not only in reach and view field tests, major ergonomic evaluations, but also in impact tests and perception evaluations. This study attempts to obtain possible correlations of human body segments from Korean anthropometric data. The investigation is focused on the description of human and dummy geometric and inertial properties. The modeling approach suggested is based on rigid body dynamics using fifteen individual body segments connected by joints. The segments are joined at locations representing the physical joints of the human body and have the mass of the body between body joints. For visualization, a three-dimension graphic technique is used ...

• International Journal of Human Ecology
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• 제7권2호
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• pp.97-110
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• 2006

A conceptual framework, based on a curriculum model of family life education content, and on a schema for analyzing explicit use of theory, was developed to discern the substantive themes of programs and the role of theories in publications on programs for families in the Korean family studies literature. Seventy two journal articles published between 1990 and 2002 were analyzed. The results revealed that the Korean family life education programs dealt with the breadth of topics, but most particularly internal family dynamics and interpersonal relationships, and utilized theoretical concepts as input and output in a different level: explicit, implicit, or no use of theories. Implications for future research and practice in Korean family life education are discussed, including gaps in the substantive foci of programs, and aligning programs more closely with theory.