• Journal of the Korean Wood Science and Technology
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• v.41 no.5
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• pp.432-439
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• 2013

The aim of this study was to investigate the processes for evaluating the allowable bending stress. The confidence levels and the size-adjustment in standards were reviewed with experimental data. The results show that, (1) KS F 2152 was more strict than others overseas standards due to the higher confidence level. The 5% NTL of bending strengths by a method in KS F 2152 were lower than the overseas standards and more specimens were required for evaluating the structural properties according to KS F 2152. (2) Due to the absence of size-adjustment method in domestic standards, the specified size and the exponential parameters on the size-adjustment equation were reviewed by size factors. The specified size (width: 286 mm, length: 6096 mm), and the exponential parameters (w: 0.29, l: 0.14) will be suitable for developing the allowable bending stress in domestic standard. (3) The size adjusted allowable bending stresses of No. 2 grade Korean pine were lower than the allowable stresses tabulated in KBC even though less strict method (75% confidence level) to calculate 5% value was used. The allowable stresses tabulated in KBC are needed to be reviewed by continuous experimental data.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.549-552
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• 2004

This paper investigated the drying and autogenous shrinkage of high performance concrete(HPC) with mixture adjustment under various specimen size. For fresh concrete properties, HPC with mixture adjustment need a higher dosage of SP agent due to fluidity reduction, and a larger dosage of AE agent due to the reduction of air content. HPC with mixture adjustment exhibited a smaller strength development than control HPC. For drying shrinkage, an increase in specimen size occurred with small expansion during water curing and at air curing, less drying shrinkage was observed. Autogenous shrinkage was not affected by specimen size. Autogenous shrinkage of HPC with mixture adjustment exhibited less than half of control HPC.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.854-863
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• 2008

A high attention has been paid on the running safety of Korean high-speed train, KTX. In running of KTX on bridge, the running unsafety problem issued from a resonance phenomenon of bridge, which was usually caused by the periodic wheel-loads of train. Therefore, many researches on this running safety of train on bridge have been conducted by domestic or foreign researchers. In this paper, for PSC box-girder bridge which is the representative high-speed railway bridge type, some numerical analyses on the dynamic characteristics of bridge with the non-periodic wheel-loads through vehicle size adjustment were performed. These numerical analyses shows the fact that the resonance phenomenon on bridge was mitigated through vehicle size adjustment. Additional numerical analyses on the vibration reduction of bridge in accordance with the location of size-adjusted vehicle were performed. From these results, it was represented that the adjustment of vehicle size has an effect on the running safety of train as well as the ride comfort.

• Journal of the Korean Home Economics Association
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• v.38 no.3
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• pp.25-42
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• 2000

To examine toddlers’adjustment in child care centers according to the quality of child care environment, the followings were asked; 1. Are toddlers’adjustment in child care centers different by toddlers’individual characterisitcs, caregiyer’s individual characteristics, and/or care center variabless\ulcorner 2. Are the quality of child care center different by caregiver’s individual characteristics and child care center variables\ulcorner 3. Are toddlers’adjustment in child care centers different according to the quality of child care center\ulcorner Forty caregivers and 108 toddlers in 40 child care centers in Inchon were randomly selected. After 2 hours of observation in each child care center, the quality of child care environment were rated using Infant/Toddler Environment Rating Scate(ITERS) by 2 observers and toddlers’adjustment in child care centers were rated by caregivers using the Preschool Adjustment Questionnaire(PAQ). Toddlers’adjustment in centers were different by toddlers’gender, caregiver’s age, caregiver’s educational level, group size, and the adult/child ratio. The quality of child care environment of child care centers was different by caregiver’s age, caregiver’s career level, the length of working time, group size, and the adult/child ratio. Finally, toddler’s adjustment in child care centers were significantly different by the quality of child care environment of child care centers.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05b
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• pp.67-68
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• 2010

Recently, there were not enough studies regarding the mix adjustment and changes of normal physical properties of slump flow type concrete in domestically. Therefore in this paper, it is aimed securing the fundamental data about flow its mix design method by experimental research. The experiment includes the adjustment of the way for slump flow type concrete by the variation of size of coarse aggregate. In the result, it is advisable raising the ratio of fine aggregate and unit water amount by considering the specific surface when increasing the Gmax size.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.35-53
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• 2018

Recently, there is a growing interest in housing policy to prepare for the aging society. The purpose of this study is exploring the factors that explain housing consumption and adjustment of pre-retirees after retirement. 1,351 samples were collected from A bank and analyzed. There categories of housing consumption adjustment were considered including downsizing, maintain, and upsizing. Gender, educational level, housing size, housing type, asset size, and willingness to work after retirement were examined to see if they can explain the housing consumption adjustment of pre-retirees using orderd- probit model. The finding of this study is that housing size, asset size, and willingness to work after retirement statistically significantly explain the housing consumption adjustment. At specific, firstly, if the current size of the housing is relatively large, it is highly likely to downsize housing after retirement. Second, pre-retiree whose assets exceeded 1 billion won were more likely to scale up housing than assets of over 300 million to less than 500 million won. Lastly, unless there is absolutely no willingness to work after retirement, it is indicated that it intends to up-sizing consumption rather than down-sizing adjustment. The results of this study can provide useful information for the housing policy in order to prepare for the (post) aged society.

• Journal of the Korean Statistical Society
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• v.30 no.2
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• pp.281-290
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• 2001

Symmetric estimation and recursive mean adjustment are considered to construct tests for the doble unit root hypothesis for both parametric and semiparametric time series models. It is shown that simultaneous application of symmetric estimation and recursive mean adjustment yields the most powerful test. Moreover, size property of the semiparametric test based on the simultaneous application is bet among all semiparametric tests.

• Management & Information Systems Review
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• v.22
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• pp.1-23
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• 2007

This paper investigates the relationships between exports, firm size, and firm dynamics. It is based on a longitudinal data covering listed firms in the Korean manufacturing industry. We found the stylized fact that the probability that a firm is exporter increases with firm size. A regression model for the determinant of export/sales ratio including dynamic adjustment process is tested on a cross-section sample for the year 2001. Empirical findings suggest that there is a positive and inversely U-shaped relationship between firm size and export/sales ratio, just for basic material and capital good industry. Except for firm size, the hypotheses concerning human capital intensity, physical capital intensity, R&D intensity, and patent are rejected. Using Granger causality test, we found that the rate of growth of total sales influences the change of the export/sales ratio with time lag for medium-sized firms. Finally, some policy implications are presented.

• Communications for Statistical Applications and Methods
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• v.22 no.5
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• pp.519-530
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• 2015

The geometric chart has proven more effective than Shewhart p or np charts to monitor the proportion nonconforming in high-quality processes. Implementing a geometric chart commonly requires the assumption that the in-control proportion nonconforming is known or accurately estimated. However, accurate parameter estimation is very difficult and may require a larger sample size than that available in practice in high-quality process where the proportion of nonconforming items is very small. Thus, the error in the parameter estimation increases and may lead to deterioration in the performance of the control chart if a sample size is inadequate. We suggest adjusting the control limits in order to improve the performance when a sample size is insufficient to estimate the parameter. We propose a linear function for the adjustment constant, which is a function of the sample size, the number of nonconforming items in a sample, and the false alarm rate. We also compare the performance of the geometric charts without and with adjustment using the expected value of the average run length (ARL) and the standard deviation of the ARL (SDARL).

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.401-406
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• 2005

According to the ubiquitous times that is new important topic, the miniature is demanded in the industry at large. The high accuracy and accumulation make the assembly equipment and the production equipment huge from the size of view. The huge equipment brings about the expensive price of the equipment, a low flexibleness and a low productivity. It makes the manufacturing equipment huge that the accuracy only depends on the mechanism stiffness. The position of two assembled parts is transformed with the global coordinate system whose datum is machine coordinate system. The purpose of this research is invention of the module that can adjust one part to the order part automatically. The module that has a function of self adjustment only takes a stiffness in assemble direction and can be moved freely in the other direction so this function makes a self adjustment. The self adjustment module reduces the tact time and also diminishes the inferior goods and makes reconfigurable machine in $\mu-part$ assembly.