• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.2
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• pp.41-50
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• 2003

In this paper, nonlinear parallel structural analyses are introduced by using the parallel multifrontal solver and damage localization for 2D and 3D crack models is presented as the application of nonlinear parallel computation. The parallel algorithms related with nonliear reduce the amount of memory used is carried out because many variables should be utilized for this highly nonlinear damage analysis. Also, Riks' continuation method is parallelized to search the solution when strain softening occurs due to damage evolution. For damage localization problem, several computational models having up to around 1-million degree of freedoms are used. The parallel performance in this nonlinear parallel algorithm is shown through these examples and the local variation of damage at crack tip is compared among the models with different degree of freedoms.

• Structural Engineering and Mechanics
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• v.49 no.4
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• pp.427-448
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• 2014

At present, the time of easy oil and gas is over. Now, the largest part of fossil fuels is concentrated in the deepest levels of tectonic structures and in the sea shelves. One of the most cumbersome operations of their extraction is the bore-hole drilling. In connection with austere tectonic and climate conditions, their drivage every so often is associated with great and diversified technological difficulties causing emergencies on frequent occasions. As a rule, they are linked with drill string accidents. A key role in prediction of these situations should play methods of theoretical modelling. For this reason, there is a growing need for development and implementation of new numerical methods for computer simulation of critical and post-critical behavior of drill strings (DSs). In this paper, the processes of non-linear deforming of a DS in cylindrical cavity of a deep bore-hole are considered. On the basis of the theory of curvilinear flexible rods, non-linear constitutive differential equations are deduced. The effects of the longitudinal non-uniform preloading, action of torque and interaction between the DS and the bore-hole surface are taken into account. Owing to the use of curvilinear coordinates in the constraining cylindrical surface and a specially chosen concomitant reference frame, it became possible to separate the desired variables and to reduce the total order of the equation system. To solve it, the method of continuation the solution by parameter and the transfer matrix technique are applied. As a result of the completed numerical analysis, the critical states of the DS loading in the cylindrical channels of inclined bore-holes are found. It is shown that the modes of the post-critical deforming of the DS are associated with its irregular spiral curving prevailing in the zone of bottom-hole-assembly. The possibility of invariant state generation during post-critical deforming is established, condition of its bifurcation is formulated. It is shown that infinite variety of loads can correspond to one geometrical configuration of the DS. They differ each from other by contact force functions.

• Korean Journal of Childcare and Education
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• v.6 no.3
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• pp.65-84
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• 2010

This study examined poor custodial grandparents' life story and care-giving experiences of their grandchildren. 8 grandparents were selected and in-depth interview and participant observation method were used. They showed a miserable life from the birth and discriminative experience of the deprivation of educational opportunities as childhood nadir experiences. They showed the regret for their inability as youth/midlife low point and financial difficulty as old life nadir experiences. In terms of care-giving experiences of their grandchildren, they showed non-voluntary care-giving, anxiety for the generational continuation of hardship, and lack of familial assistance. Poor custodial grandparents also used family-centered value, community-based social assistance, and self-assurance through their sacrifice as their adjustment strategy. Several research themes such as the importance of basic trust in childhood, the experience of financial difficulties, the importance of community-based social assistance, and self-assurance through their sacrifice were suggested for further research.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.692-697
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• 2006

The importance about the maintenance consideration of the building has a great impact and regarding the life continuation of the building the many interest is becoming intensively. The housing lot of the heart of urban at the capital region has insufficient recently and the construction of the ground complex building in solution for the insufficiency is increasing at the rapid pace. The ground complex building is brings the maximization of land use from inside the site, but maintenance consideration phase is caused by administration cost share and administration bound limit where person is concerned for a many problem point it contains. The objective of the present paper is that the building is maintain an efficiency initially and is improve in order to develop guide line for a maintenance consideration improvement from design phase. According as literature research and question research is enforce, the paper is escape problem point the maintenance consideration and is bring up guide line for the architectural plan field and the maintenance consideration improvement of the building. Result of the study is expected a help in maintenance consideration improvement during life cycle of the building

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.159-160
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• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.

• Journal of the Korean Home Economics Association
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• v.46 no.8
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• pp.55-72
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• 2008

The purpose of this study was to analyze the state of Goryoin housing in Uzbekistan and Korea. Using ethnographic methodologies, it was examined that 20 Goryoin households in Korea in relation to their usage of housing space firstly and also tried 20 Goryoin households in Uzbekistan with the same method. The following conclusion were established; 1). The majority of households in both areas preferred separated kitchen and living room areas. 2). Most households in both areas had a washing machine in bathroom and they regarded bathtub and the drain hole of the bathroom as very necessary. They all preferred separate bathroom and toilet areas in order to allow simultaneous use. 3). Their preferred seating style was chairs on sleeping and eating especially but they treated large family and guest without chairs in both areas. 4). All of them were took their shoes off and wore slippers at home usually and also had a preference for designated shoes space at the entrance to the house. 5) All of households in Uzbekistan and half of them in Korea had a carpet or mat in the bedroom or living room, both for keeping warm and aesthetic reasons. 6). The heating system of apartment in Uzbekistan was radiator and most of private houses had a modified Ondol with radiator but their preferred heating system was modified Ondol in both areas. 7). They all considered the living room as the most important housing space for family and guest in both areas.

• Structural Engineering and Mechanics
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• v.24 no.6
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• pp.709-725
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• 2006

In this paper the buckling and post-buckling behavior of slender bars under self-weight are studied. In order to study the post-buckling behavior of the bar, a geometrically exact formulation for the non-linear analysis of uni-directional structural elements is presented, considering arbitrary load distribution and boundary conditions. From this formulation one obtains a set of first-order coupled nonlinear equations which, together with the boundary conditions at the bar ends, form a two-point boundary value problem. This problem is solved by the simultaneous use of the Runge-Kutta integration scheme and the Newton-Raphson method. By virtue of a continuation algorithm, accurate solutions can be obtained for a variety of stability problems exhibiting either limit point or bifurcational-type buckling. Using this formulation, a detailed parametric analysis is conducted in order to study the buckling and post-buckling behavior of slender bars under self-weight, including the influence of boundary conditions on the stability and large deflection behavior of the bar. In order to evaluate the quality and accuracy of the results, an experimental analysis was conducted considering a clamped-free thin-walled metal bar. As this kind of structure presents a high index of slenderness, its answers could be affected by the introduction of conventional sensors. In this paper, an experimental methodology was developed, allowing the measurement of static or dynamic displacements without making contact with the structure, using digital image processing techniques. The proposed experimental procedure can be used to a wide class of problems involving large deflections and deformations. The experimental buckling and post-buckling behavior compared favorably with the theoretical and numerical results.

• Journal of Korean Academy of Rural Health Nursing
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• v.4 no.1
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• pp.31-40
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• 2009

Purpose: This research was done do identify and analyze the beginnings of the community health practitioner system in the Republic of Korea (ROK) around 1980. Method: Primary sources were collected and analyzed, mainly newspapers around 1980, the act for health service for rural areas, and other relative publications. Results: The government of the ROK was trying to solve the problem of doctorless villages and regarded the introduction of primary health care (PHC) services using registered nurses (RNs) to be an economic solution to this problem. The Korean Nurses' Association presented 'a plan for community health service' to the government party and medical association in 1976. In this plan, RNs would provide primary care at the sub-county (myun) level, and hospital would provide secondary care. The Korean Public Health Development Research Center was awarded the project 'RNs and nurse aids as CHP for primary care service and their training'. In 1977, 25 RNs began to work as PHC in 3 areas, and interim findings showed that RNs were very capable of doing PHC. The Ministry of Health and Welfare announced long term plans for health and welfare administration including a tertiary health care delivery system. RNs after training were posted to rural areas with no medical services to do medical treatment for mild cases. The Act for health services for rural areas was enacted on December 31, 1980. Enforcement Ordinance and Enforcement Regulations were enacted in 1981. In 1981, 257 CHP were selected, trained, and deployed. In 1983, the president of the ROK announced continuation of the CHP system for residents of medically vulnerable areas. The number of CHP increased from 257 in 1981 to 2038 in 1989.

• Convergence Security Journal
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• v.19 no.2
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• pp.129-136
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• 2019

The main tasks of commander and staffs in ground operations are a continuation performing the process of making decisions in various situations. Since the current decision-making process is largely dependent on qualitative methods, it is difficult to integrate with the decision-making tools associated with the 4th Industrial Revolution. The purpose of this study is to suggest the process of deriving the relative importance of the evaluation factors using the AHP with focusing on assessing the avenues of approach in IPB related to the ground operation plan. The most important aspect of IPB is the evaluation of the avenues of approach. Evaluation factors include target accessibility, observation and seasons, concealment and cover-up, ease of maneuverability, and ease of transition to adjacent access roads. The existing methods are the comparison method with evaluation factors and the analysis with the advantages and disadvantages. However, it has been criticized that they regard evaluation factors as equal importance. The results show that target accessibility has the highest score related with priority when considering the criteria.

• Journal of the Korean Society for information Management
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• v.38 no.1
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• pp.87-112
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• 2021

Volunteers in public libraries are recognized only as internal manpower, so their sustainability and effectiveness are limited because the motivation for volunteering is hardly considered. This study aims to explore the motivation for volunteering in public libraries and the factors to continuation of the volunteering, and to analyze how these factors affect volunteer satisfaction and marketing intentions. To this end, the variables in this studies including satisfaction and motivation was defined operationally based on the related research and a pilot study with several in-depth interviews. A questionnaire survey was executed with the defined variables and the survey data were analyzed statistically. The results showed that the factors of emotional and psychological motivation influenced the satisfaction and marketing intention rather than the managerial factors such as remuneration. The results indicate the need for a change in volunteer management to a relationship-oriented management method. This study is meaningful in that it expands the value of volunteers in public libraries from as managerial to as marketing resources for public libraries.