• Journal of Families and Better Life
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• v.2 no.1
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• pp.165-177
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• 1984

The purpose of this study was to investigate satisfaction with the function of interior space of apartment and factor which influence it, and then to provide housing practitioners with basic data for more desirable apartment interior environment. On the basis of the review of literature, questionnaire was developed. The sample was classified into type of unit floor plan and house size of 17 districts in Seoul. 139 households were selected in three districts which were the first three regions of high apartment density. Data were analyzed by computer using frequency, percentage, mean, standard deviation, F-test, Duncans multiple range test, η2 , person's product moment correlation coefficient. the results are as follows: Factors which influence satisfaction with the functionality of interior were household size and family life cycle as sociodemographic variable, and type of unit floor plan as physical variable. It was shown that the satisfaction with the functionality of interior was related to satisfaction with the external environment. More specifically, (1)the smaller a household size was the more the owner became satisfied. (2)households were in the stage of establishment in the family life cycle and households with C type of unit floor plan showed higher degree of satisfaction. (3) satisfaction with the functionality of interior had positibly related to satisfaction with the external environment.

• Journal of the Korean Society of Safety
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• v.10 no.2
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• pp.24-31
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• 1995

This paper shows the fatigue durability test method for vehicle suspension systems. Durability should be assured for the safe driving during vehicle life cycle. A computer simulation for the vehicle dynamics was used to obtain dynamic loads that were required for the fatigue durability test. Durability tests were done for an Important load-carrying component of the suspension system. Stress analyses using stresscoat and strain gages were also done for the component. This study demonstrated an effective method for the fatigue durability test.

• Journal of the Korean Electrochemical Society
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• v.6 no.4
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• pp.242-249
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• 2003

Zn electrode was widely used as an anode material in alkaline battery systems in highly concentrated KOH electrolyte, however it was well known that its cycle life is significantly shortened by growth of dendrite due to the high dissolution of $Zn(OH)_2$ and rapid electrochemical reaction. In this study when by the additives such as $Ca(OH)_2$, Citrate, tartrate and Gluconate were added to $40\%$ KOH electrolyte at solution temperature of $25^{\circ}C$ and the amount of $5wt\%\;Pb_3O_4$ was mixed to Zn electrode and then the effect of $Pb_3O_4$ and additives on the electrochemical behavior of Zn electrode was investigated by Potentiodynamic Polarization Curves, Cyclic Voltammetry, Accelerated Life Cycle lest, and SEM image analyses. The addition of $Pb_3O_4$ reduced the corrosion rate of Zn electrode. The corrosion potential of Zn electrode with $Pb_3O_4$ was higher or lower than that of pure Zn electrode however was not influenced practically to the open circuit voltage. And the addition of 4 type additives had an important role in improving both cycle life in accelerated cycle life test and corrosion resistance. Furthermore the additive of Tartrate indicated comparatively a good effect to corrosion resistance as well as charging-discharging property Improvement among those four type additives.

• Journal of Family Resource Management and Policy Review
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• v.28 no.1
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• pp.13-25
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• 2024

The rate of single-person households has been increasing all over the world, and there has been a particularly rapid increase in them in Korea. Single-person households show unique and various characteristics related to the reasons for becoming a single-person household, gender, life cycle, and so on. Thus, research needs to focus on the specific groups of single-person households in order to provide tailored policies and programs. This study segmented single-person households in three groups based on life cycle: young, middle-aged, and older adults. Differences in the level of healthy lifestyle, as well as factors affecting that, were investigated according to the groups. The data were collected in 2022, with 237 respondents from single-person households in Kimpo. Descriptive statistics, t-test, ANOVA, and multiple regression analysis were conducted. The overall level of healthy lifestyle was found to be significantly higher for young adults compared to older adults. Results from multiple regression show that significant factors related to the healthy lifestyle of single-person households were gender, educational attainment, whether becoming a single-person household was voluntary, and whether the respondents had experienced discrimination as a single-person household. Significant factors differed by the sub-categories of the healthy lifestyle scale. This study has implications related to discovering differences in the level of healthy lifestyles of single-person households through examining the factors affecting it according to life cycle.

• Journal of Welding and Joining
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• v.27 no.6
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• pp.49-54
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• 2009

In this study, the numerical analysis model for fatigue life prediction of welded structures are presented. In order to evaluate the structural degradation of welded structures due to fatigue loading, continuum damage mechanics approach is applied. Damage evolution equation of welded structures under arbitrary fatigue loading is constructed as a unified plasticity-damage theory. Moreover, by integration of damage evolution equation regarding to stress amplitude and number of cycles, the simplified fatigue life prediction model is derived. The proposed model is compared with fatigue test results of T-joint welded structures to obtain its validation and usefulness. It is confirmed that the predicted fatigue life of T-joint welded structures are coincided well with the fatigue test results.

• Smart Structures and Systems
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• v.16 no.4
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• pp.743-758
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• 2015

This paper presents an advanced life cycle cost (LCC) analysis of a ground source heat pump (GSHP) system and suggests a smart operation mode with a thermal performance test (TPT) and an energy pile system constructed on the site of the Incheon International Airport (IIA). First, an economic analysis of the GSHP system was conducted for the second passenger terminal of the IIA considering actual influencing factors such as government support and the residual value of the equipment. The analysis results showed that the economic efficiency of the GSHP system could be increased owing to several influential factors. Second, a multiple regression analysis was conducted using different independent variables in order to analyze the influence indices with regard to the LCC results. Every independent index, in this case the initial construction cost, lifespan of the equipment, discount rate and the amount of price inflation can affect the LCC results. Third, a GSHP system using an energy pile was installed on the site of the construction laboratory institute of the IIA. TPTs of W-shape and spiral-coil-type GHEs were conducted in continuous and intermittent operation modes, respectively, prior to system operation of the energy pile. A cooling GSHP system in the energy pile was operated in both the continuous and intermittent modes, and the LCC was calculated. Furthermore, the smart operation mode and LCC were analyzed considering the application of a thermal storage tank.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.4
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• pp.135-147
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• 2018

There has been a recent increase in the interest towards founding companies and in line with the South Korean Government's policy on start-up support, discussions are rife about the effect of entrepreneurship on the management and performances of these companies. To enhance the competitiveness of SMEs, it is expedient to acquire and deploy consistent entrepreneurship, differentiate corporate resources, ensure the appropriate utilization of resources and the integration of such factors in response to the changing environment. This research examines relationships among entrepreneurship, three components of corporate capabilities, dynamic capability and technical performance based on resource-based view and the dynamic capability theory. The authors also investigate the moderating role of corporate life cycle. To test the hypothesis, we conducted a survey on 352 technologies -innovative SMEs located in South Korea via professional research institutes. The findings confirm the hypothesis that SMEs' entrepreneurship has a positive effect on three kinds of corporate capabilities (e.g., marketing, R&D, operations capability), and it had a positive effect on dynamic capability, whiles dynamic capability also had an influence on technical performances. The findings also confirmed the hypothesis that corporate life cycle moderates the relationship between dynamic capability and technical performances respectively. The research implications for both practitioners and academicians are discussed.

• Journal of Korean Society for Quality Management
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• v.41 no.3
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• pp.327-335
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• 2013

Purpose: The purpose of this study is to suggest the modified 'Korean Standard-Quality Excellence Index' model and analyze the improvement effect with survey data by comparing the properness between current and suggested model result. Methods: The collected data through the survey were analyzed using paired t-test and unbalanced ANOVA method for testing the consistency of two customer satisfaction evaluating categories and comparing the current model to suggested model for confirming the improvement of performance. Results: The statistical analysis result shows that adjusted model using prior information improves the consistency between two customer satisfaction in case of short life-cycle product. Also long life-cycle product case, the result shows difference gap decreasing with same direction. Conclusion: Considering statistical model for QEI reflecting the characteristic of product group such as life cycle seems to be meaningful. Since index may be compared yearly base for checking the trend, careful approaching without big change should be considered for application.

• Journal of the Korean Geosynthetics Society
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• v.1 no.1
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• pp.53-61
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• 2002

Even though a lot of laboratory and field tests for asphalt pavements using geosynthetics have been conducted recently, any rational and systematic analysis for the economic efficiency of the asphalt pavement systems reinforced by using geosynthetics has not been proposed yet. In this study, the economic analysis considering the traffic characteristics for the glass fiber sheet reinforced asphalt pavement was performed using the Life Cycle Cost Analysis(LCCA) which is commonly used for the economic analysis technique. The economic efficiency for the glass fiber sheet reinforcement and the traffic characteristics was examined by applying the test results from the literature review to the economic analysis model.

• Journal of Electrical Engineering and Technology
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• v.13 no.4
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• pp.1759-1768
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• 2018

The energy density, power density and ohm resistance of battery change significantly as results of battery aging, which lead to decrease in the accuracy of the equivalent model. A parameter identification method of the equivale6nt circuit model with 3 R-C branches based on the test database of battery life cycle is proposed in this paper. This database is built on the basis of experiments such as updating of available capacity, charging and discharging tests at different rates and relaxation characteristics tests. It can realize regular update and calibration of key parameters like SOH, so as to ensure the reliability of parameters identified. Taking SOH, SOC and T as independent variables, lookup table method is adopted to set initial value for the parameter matrix. Meanwhile, in order to ensure the validity of the model, the least square method based on variable forgetting factor is adopted for optimizing to complete the identification of equivalent model parameters. By comparing the simulation data with measured data for charging and discharging experiments of Li-ion battery, the effectiveness of the full life cycle database and the model are verified.