• Wind and Structures
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• v.14 no.5
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• pp.435-447
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• 2011

A Computational Fluid Dynamics model is presented in this study for the simulation of the complex fluid flows with free surfaces inside the Tuned Liquid Column Dampers in horizontal motion. The characteristics of the fluid model of the TLCD in horizontal motion include the free surface of the multiphase flow and the horizontal moving frame. In this study, the time depend unsteady Standard ${\kappa}-{\varepsilon}$ turbulent model based on Navier-Stokes equations is chosen. The volume of fluid (VOF) method and sliding mesh technique are adopted to track the free surface of water inside the vertical columns of TLCD and treat the moving boundary of the walls of TLCD in horizontal motion. Several model solution parameters comprising different time steps, mesh sizes, convergence criteria and discretization schemes are examined to establish model parametric independency results. The simulation results are compared with the experimental data in the dimensionless amplitude of the water column in four different configured groups of TLCDs with four different orifice areas. The predicted natural frequencies and the head loss coefficient of TLCDs from CFD model are also compared with the experimental data. The predicted numerical results agree well with the available experimental data.

• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.44-54
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• 2014

This paper suggests two kinds of reaction control system command generation methods for upper stage attitude control of launch vehicles. The reaction control system is assumed to consist of two sets of three nozzles. One operation technology is based on mixed attitude error functions, and the other is based on command mixing functions. Both are compared via simulations. The simulation results show that the latter is comparatively preferable in terms of interference among control axes, independency of controller design and analysis among axes, and prediction of flight performance of each control axis.

• Journal of the Korean Home Economics Association
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• v.37 no.10
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• pp.123-133
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• 1999

The purpose of the study was to develop the parenting style scale which is reflecting cultural background of Korean parent's parenting for their children. The instalment was designed based on the literature reviews and on the Baumrind's parenting style. A total of three hundred and sixty two mothers whose children from first and second grade in elementary school completed the Questionnaires. The questionnaires consisted with the items addressing different types of parenting style which include love and care, encouragement of independence, enjoyment in parenting, communication, control, control of aggressiveness, strategies of control , request of maturity. Factor of analysis was applied to examine validity of Korean parenting style scale. Based on the factor analysis, 33 items selected for final questionnaire and two factors discovered. The first factor which named 'warmth'included 20 items such as love and care toward their children, communication, enjoyment in parenting, encouragement toward independency. The second factor which named'control'included 13 items such as control of children's behavior and discipline of children. Warmth factor accounted for 46% of variance and control factor accounted for 18% of variance. Internal consistency was also checked. Although warmth and control factor represented a moderate internal consistency, control factor showed lower correlations then warmth factor. The reliability estimates (Cronbach alpha) were. 87 and 71 for warmth and control factor respectively. Korean parenting style scale can be used to address the appropriateness of Baumrind's theoretical assumptions in parenting style as well as to examine parenting style for Korean population. However, this instalment was developed with Korean mothers only. Further analysis need to be addressed with fathers.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.528-531
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• 2004

This paper presents the design and implementation of a QoS based IrDA in mobile phones. The IrDA standards have arised from the need to connect various mobile devices together. But currently, we have a difficult to connecting various mobile devices together. The difficult thing is to adjust the minimum turn around time. The minimum turn around time in IrDA deals with the time needed for a receiver circuit to recover following saturation by transmissions from the same device (turn around latency). This parameter corresponds to the required time delay between the last byte of the last frames sent by a station and the point at which it is ready the first byte of a frame from another station. This parameter comes into play when the link is turned around and is negotiated independency for each station. We solve this matter by using the Dynamic Adjustment Algorithm (DAA). The dynamic adjustment algorithm adjusts the minimum turn around time according to the numbers of devices. We apply our direct adjustment algorithm to our QoS based IrDA in mobile phones and show the improved performance of connection with various mobile phones together.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.12
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• pp.3317-3328
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• 1995

The objective of the present study is to predict the characteristics of heat and mass transfer around an evaporative condenser. Numerical calculations have been performed using multi-zone method to investigate heat transfer rate and evaporation rate with the variation of inlet condition(velocity, relative humidity and temperature) of the moist air, the flow rate of the cooling water and the shape of the condenser tube. From the results it is found that the profile of heat flux is the same as that of evaporation rate since heat transfer along the gas-liquid interface is dominated by the transport of latent heat in association with the vaporization(evaporation) of the liquid film. The evaporation rate and heat transfer rate is increased as mass flow rate increases or relative humidity and temperature decrease respectively. But the flow rate of the cooling water hardly affect the evaporation rate and heat flux along the gas-liquid interface. The elliptic tube which the ratio of semi-minor axis to semi-major axis is 0.8 is more effective than the circular tube because the pressure drop is decreased. But the evaporation rate and heat flux shown independency on the tube shape.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.33-41
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• 2007

Service-Oriented Architecture(SOA) define the interaction method between two computing entities that one entity performs a unit task instead of another entity. This, unit task, is called "Service" and interaction of these services should have independency and loosely coupled task. The effect of SOA's main functions such as loosely coupled task and independent interoperability with influence the possibility of flexible message communication between different way and different users. In this article, we analyzed the performance about system stabilization between general web service and SOA based application that implemented through WCF based messaging framework using .NET Framework and integrated data presentation method. As the result of test, we confirmed that SOA environment using WCF have more advantages.

• Journal of the Korean housing association
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• v.21 no.2
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• pp.77-86
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• 2010

Korean population is now aging at an unprecedented rate. Fertility decline together with rapid improvements in life expectancy is the dominant demographic trend. As human life and housing environment are inseparably related to each other, the importance of conditions of housing environment for active aging among seniors has been received considerable attention as vital ones to expand the independency period of seniors. The purpose of this case study is to identify relationships between environmental affordance and perceived holistic health of the active elderly living in a retirement community located in Seoul. With spending time personally in the community to observe their lives, the researcher could be in close rapport with the residents. After the period of getting familiar with each other, in-depth individual interview and focus group interview were conducted and then, qualitative analysis was completed. As a result, general evidences showed that perceived seniors' health on the whole was improved physically, socially, and mentally by moving into the community providing appropriate environment affordance with the older adults. The study presents that retirement relocation into an improper environment may be a negative challenge, however, it may positively influence on the health and well-being of those who live there if the environment properly supports seniors‘ needs physically and socially

• Health Policy and Management
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• v.17 no.1
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• pp.75-93
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• 2007

This research purposed to analyse the diversity of the long-term care system based on the dependency/independency of the aged. For this purpose, we divided the long-term care systems to three components; form of benefit, generosity of benefit and delivery system. Form of benefit is whether the benefit is cash or in-kind, and the generosity of benefit is related to the level and coverage of benefit. The last concerned to focus on provider and user selection. According to this, we tried to make an ideal type of long-term care in the perspective of citizenship and consumerism. As a result, we established four types of long-term care system; active citizen type, passive citizen type, latent citizen type, and family dependent type. And we investigated Austria, Sweden, Germany and Korea for each type empirically.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.300-307
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• 2002

Partial penetration welding joint is defined as groove welds welded from one side, without steel backing or groove welds welded from both sides but without back gouging. So it has an unwelded portion at the root of the weld. Study of partial penetration weldment fracture behavior includes residual stress analysis and fracture analysis. The J-integral loses its path independency in residual stress field. Therefore, it is necessary to introduce a new J-integral, J, which is defined including the effect of plastic deformation and thermal strain. In this study, theoretical formulation and program were developed for the evaluation of J-integral for the crack tip located in the weldment. Evaluations of fracture behavior were performed for partial penetration multi-pass weldment of 25.4mm thick plate by J-integral. From a point of fracture in partial penetration multi-pass welding, it seemed to be better to control root face smaller than 6.35mm.

• The KIPS Transactions:PartD
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• v.10D no.4
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• pp.735-744
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• 2003

This paper presents details of the design and implementation of a report generator, Moonlight, which supports to design the report form from DB or data sources and print it to the printer. Also this paper defines the detailed model of the report system, the architecture and behavior of MoonLight, and the components of the report form, and also shows algorithms to make the report template and print the report bound to the data source. Moonlight takes advantage of XML language for the report template form. And also it is implemented by Jana language to take the advantage of platform independency. This paper also shows the results of run-time performance of Moonlight which is measured with the time to construct page objects of a report and the time to render the page objects to the print images, respectively.