• Survey Research
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• v.4 no.2
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• pp.63-86
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• 2003

The objective of this study was to investigate the existence of starting point bias in the bidding game contingent valuation elicitation technique when determining willingness to pay (WTP) for improving the qualify of running water in Seoul and its vicinity. Of all existing contingent techniques, the bidding game most closely mimics the normal price taking behavior in local markets. Three different starting points (low, medium and high) were used to determine WTP and the existence of starting point bias in the meanwhile respectively. The respondents were randomly assigned to the three different starting point groups in order to ensure homogeneity, so that any variation seen in WTP could be attributed to the starting point effects. And a pretested interviewer-administered questionnaire used to elicit WTP. Non-parametric test and the logit model were used to analyze the data for evidence of starting point bias. In this instance, the high starting point group had a high WTP, and low starting point group had a low WTP. This means there exist starting point bias in estimating WTP by bidding game in this instance. This finding might signal that people may actually be making up their minds on the maximum amount they are willing to pay for running water service as a bidding iterating is going on and is influenced by the starting point used in the bidding game. The problem of slaking point bias can be avoided if the respondent is asked directly for the maximum WTP without payment cards or a bidding game. But such a question is perceived as being very difficult to answer and this leads to problems of non-response and being unrealistic.

• Journal of the Korean GEO-environmental Society
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• v.11 no.11
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• pp.55-62
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• 2010

The settlements by liquefaction seldom occur uniformly because of soil homogeneity, however differential settlements are major cause of the damages to structures. From the past researches, author paid attention to the fact that stress history during undrained cyclic shear process affects greatly on the volumetric strains of the post-liquefaction. Therefore, the effect of the residual shear strain in cyclic shear process was examined in this study. The experiment apparatus based on strain control with volumetric strain control device was used for the study to investigate the effect of the residual strain on the relationship between volumetric strain and effective stress of clean and granite sandy soil. It could be seen an insignificant difference in the volumetric strain after liquefaction under various residual shear strain conditions in the case of clean sand. On the other hand, in granite sandy soil, the volumetric strain after liquefaction was small when the lower level of the residual shear strain was applied. And, the residual shear strain during cyclic shear affected the shape of the relation curve between effective stress and volumetric strain as well.

• Polymer(Korea)
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• v.24 no.3
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• pp.389-398
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• 2000

Transparent, abrasion resistant coatings with 4~13 ${\mu}{\textrm}{m}$ thickness were prepared by spin-coating on polycarbonates with organic/inorganic hybrid solutions, followed by UV curing and heat treatment at 12$0^{\circ}C$ for 12 hours. The coating solutions were composed of inorganic phase and organic phase in 0:100, 20:80, 30:70, 50:50, 80:20 wt% ratios, respectively, mixed with photoinitiator, senaitizer and surfactant. The inorganic phase was formed by sol-gel reaction of TEOS and silane coupling agent MPTMS in 1 : 2 or 2 : 1 molar ratios, the organic phase consisted of difunctional urethane acrylate oligomeric resin, multifunctional acrylate TMPTA and HDDA in 4 : 3 : 3 wt% ratio. The coating systems were investigated by FT-IR, $^{29}$ Si-NMR spectra. In addition, TGA/DSC for thermal analysis and SEM, AFM observation for coated surface were examined. Gererally, the homogeneity of phases, the surface smoothness of coating and abrasion resistance were improved with the higher content of inorganic component. Namely, coating system with below 10 $\AA$ surface roughness and T$_{g}$ of 15$0^{\circ}C$ showed only 10% decrease in light transmittance after abrasion test, whereas uncoated polycarbonate substrate exhibited 46% decrease..

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.307-314
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• 2006

Elevation differences within a paddy field relate strongly to plant health, crop homogeneity, and pest control. For precision agriculture (PA), the elevation within a field should be precisely controlled. We analyzed variation in elevation within two rice paddies over one crop cycle. The study took place in two rectangular plots (Field A and Field B, each $50m{\times}30m$). Elevations within the two plots were measured by a laser-equipped surveying instrument, that could determine elevations to precisions of 1 mm. The test fields were divided into grids with 30 squares; elevation was measured at the center of each $5{\times}10-m$ grid square. This study measured elevation during nine observation periods from pre-plowing to post-harvest. Descriptive statistics showed the highest elevations after plowing due to soil disturbance. One-way analysis of variance (ANOVA) revealed significant elevation differences before and after plowing and transplanting, although elevations were similar over the period of crop growth. Comparison of pre-plowing and post-harvest data showed differences in elevations, indicating that elevation changes occurred during plowing, rice transplanting, plant growth, and harvesting. In summary, the above statistical analyses indicated that elevation changes occurred due to plowing but not during the plant growth season or due to harvesting.

• The Korean Journal of Nuclear Medicine
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• v.24 no.1
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• pp.29-36
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• 1990

Most of the diagnostic methods currently used for the detection of neoplastic masses provide indirect evidence. To obtain greater specificity in the interpretation of neoplasias by in vivo methods, the immunological approach appears to be most promising. Two problems that interfered with progress in this field were the lack of tumor specific antigen and the lack of well-defined and reproducible antibodies. To improve the sensitivity and specificity of radioimmunoscintigraphy as a technique for tumor localization, the use of monoclonal antibodies, fragments of antibodies and single photon emission computerized tomography (SPECT) are reasonable. The obvious advantages of monoclonal antibodies are their homogeneity, their specificity for the immunizing antigen and the reaction with a single determinant-thus no large immunecomplexes with antigen are formed. Monoclonal antibody technique has recently provided an opportunity to reevaluate the role of nuclear medicine for the diagnosis of malignant diseases by using the immunological approach. Out first results by means of radioimmunoscintigraphy of CEA and CA 19-9 producing tumors using a cocktail of fragments F $(ab')_2$, of mocolonal antibodies to CA 19-9 and CEA labeled with $^{131}I$ (IMACIS-1) are reported. The aims of this investigation was to evaluate the role of immunoscintigraphy in patients with colorectal and other cancers for diagnosis of local recurrences and metastasis. This report contains results of the first 8 colorectal and pancreas cancer patients with the elevation of the level of serum CEA and/or CA 19-9. IMACIS-1 was injected intravenously during 30 minutes in 100 ml saline solution after skin test. Planar scintigrams were recorded 3, 5 and 7 days after the injection of the IMACIS-1. Anterior, lateral and posterior views of the liver as well as anterior and posterior views of the pelvis were obtained in each patients as an $^{131}I-antibody$ image. We were able to localize exactly the malignant process with the double-nuclide double-compound $^{99m}Tc\;^{131}I$ (Tc+l) scintigrams. In Tc & I double-nuclide scintigraphy, computer subtraction display provided more clear localization of the tumor. We compared the results of radioimmunoscintigraphy with CT, ultrasonograms, conventional scintigrams. The results were as follows: 1) The sensitivity and specificity of radioimmunoscintigraphy using the fragments $F(ab')_2$ of the cocktails of CEA and CA 19-9 monoclonal antibodies were 80% and 100% respectively. 2) Tumor detection rate was not proportionated to the level of serum tumor markets. 3) Second tracer technique was essential for tumor localization as an anatomic landmark using double-nuclide scintigraphy. 4) A slow infusion of the antibodies was necessary to prevent the formation of large immune complexes. 5) Tumor/non-tumor radioactivity was most elevated at 7 days delayed imaging. 6) Using planar scintigraphic technique of $^{131}I$ labeled monoclonal antibodies are possible for imaging most of the tumors.

• Journal of Family Relations
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• v.22 no.4
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• pp.181-204
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• 2018

Objectives: The aim of this study is to integrate the results of the previous studies from 1900 to 2016 according to the types of dependent variables individually and statistically to obtain the results of the overall level of the marital education program I need to figure it out. In other words, the general and valid study on the overall effectiveness of the marriage education program will lead to more concluded conclusions and draw up an integrated and holistic conclusion about the effectiveness of the marriage education program. Method: The purpose of this study was to investigate the effect of married couples' education program on married couples' education program. The results of this study are as follows. First, Comprehensive Meta-Analysis. In other words, funnel plot, forest plot, and trim & fill were used to analyze all the variables related to the education of the couple, and homogeneity test After choosing an analytical model for the analysis, we calculated the 'standardized mean difference' effect size (d) that can compare different individual studies through the analytical model. The results of this study are as follows. Results: The purpose of this study was to investigate the overall effect size of domestic couples education programs after 1990, and to investigate the effect sizes of dependent variable types and program - related variables. First, the total effect size of the domestic marriage education program was close to the level of the large effect size and had a substantial and preventive effect. Self-esteem, communication, marital adjustment, emotion, and self control have a substantial and prophylactically significant change depending on the type of subordinate variables related to the marital education program But there was no change in origin family and life satisfaction. Third, as a result of the categorization of the dependent variable categorization of the Korean couple education program, it was found that the marital relations of the participant in the individual inner and the marital relations The effect was significant enough to change. Fourth, Korean couple education program was most effective when mixed age couples were participated in various family life cycle. Conclusions: Based on the results of this study, it is necessary to study more deeply about marital education program effect of marriage education for various special groups such as married couples who are in a crisis of divorce, . It also means that the results of the research for the last 30 years from 1900 to 2016 were comprehensively and systematically summarized through meta - analysis. The results of this study provide information on how to provide the most effective couples education programs for practitioners in the field. The result of this study will be the data of judgment about how to organize the marital education program for people of any ages and characteristics in the future.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.234-242
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• 2021

The purpose of this study was to examine the effectiveness of drama therapy in Korea by using method of meta-analysis. For the purpose of this study, master's theses, doctoral dissertations, and journal articles published in Korea up to June, 2021 were systematically reviewed. As a result, a total of 18 studies were eligible for the inclusion criteria. The mean effect sizes and test for homogeneity of effect size(Q-statistic) were analyzed by using Comprehensive Meta-Analysis Software 2.0. The main findings of the study were as follows. First, the average effect sizes for drama therapy were ES=1.325 of self-esteem, ES= -1.230 of depression and anxiety, ES= 1.025 of stress, ES=1.018 of sociability, Es=0.907 of emotional intelligence, ES= 0.897 of psychological wellbeing. Second, by analysing the moderate variables of the effect size for drama therapy, 'adult', 'the number of session' 'performance based drama therapy' of self esteem were statistically significant. Based on this study results, the drama therapy research and practice implications in Korea were discussed.

• Journal of the Korean Geotechnical Society
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• v.38 no.12
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• pp.113-123
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• 2022

The required density relationship according to the press pressure of the floating die method and the homogeneity of the density distribution in the buffer block was evaluated to analyze the manufacturing characteristics of engineering scale bentonite-sand buffer blocks. In addition, the thermal conductivity was measured and compared with that of the pure bentonite buffer block to evaluate the level of thermal conductivity performance improvement of the bentonite-sand buffer material. As a result, it was confirmed that the standard deviation of dry density decreased to 0.011 and showed a homogeneous density distribution under the condition of press pressure greater than 400 kg/cm². Furthermore, as a result of the thermal conductivity test, the thermal conductivity of the buffer with optimum moisture content conditions was 1.345 and 1.261 W/(m·K) under the press pressure of 400 and 600 kg/cm², respectively. It increased by 16.1% and 11.0% compared to the pure bentonite buffer material. Based on the results of this study, it is judged that it can be used as fundamental data for manufacturing a homogeneous bentonite-sand buffer block on an engineering scale.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.203-215
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• 2017

Delirium is an acute confused state associated with poor outcomes among hospitalized long-term care hospital elderly patients. This study was conducted to examine the effects of acomfort promotion program based on Kolcaba's comfort theory for prevention of delirium among elderly patients who have been hospitalized in long-term care hospitals. The study used was a quasi-experimental type, with two groups of patients; those who received their usual care plus comfort nursing intervention (n=34) and those who only received usual care methods. Using the IBMSPSS/PC (Version 21), the homogeneity of the control and intervention group wereevaluated by the chi-squared test and an independent t-test, and all collected data wereanalyzed. Hypotheses were tested by independent t-tests and repeated measures of ANOVA. Delirium occurred at a rate of 2.9% (1/34) in the intervention group and 14% (5/34) -in the control group ($x^2=3.98$, p=0.047). The severity of the delirium in theintervention group was lower than that of the control (t=2.27, p=.027). The duration of delirium was 2days in the intervention group and 2-10days in the control group, indicating delirium in the intervention group lasted for a significantly shorter period ($x^2=3.22$, p=0.048). According to the change of time, the intervention group showed improvement in all areas including comfort scores (F=108.85, p<0.001), anxiety scores (F=63.39, p<0.001), depression scores (F=89.78, p<0.001), quality of sleep scores (F=63.63, p<0.001), and pain scores (F=93.64, p<0.001). In conclusion, elderly patients who were admitted to nursing homes were advised to participate in nursing intervention,which effectivelyprevented delirium based on the Kolcaba's comfort theory of physical, psychological, spiritual, social, cultural and environmental approaches to prevent delirium. Therefore, it is necessary to extend the program for prevention of delirium in the physical, psychological, spiritual, social, cultural, and environmental contexts to prevent delirium in geriatric hospitalized elderly patients.

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.53-61
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• 2002

An Aquifer test was carried out on five boreholes to determine the hydrologic anisotropy and the major groundwater flow direction in the aquifer system of the study area. With an assumption of the aquifer's anisotropy and homogeneity, the major transmissivity(T(equation omitted)), the minor transmissivity( $T_{ηη}$ ), and primary tensor direction ($\theta$) for each borehole were determined from the test. Besides the boreholes BH-1, BH-4 and BH-5, the anisotropy transmissivity tensor values of BH-2 and BH-3 did not correspond with the assumption. Thereafter the values were plotted on the polar coordinate, and showed that the tensor values were out of the anisotropy ellipsoid due to the high heterogeneity of BH-2 and BH-3 comparing with the other boreholes. Therefore. the anisotropy of the aquifer was examined from BH-1, BH-4. and BH-5. In BH-1, T(equation omitted) is 171.9 $\m^2$/day. $T_{ηη}$ is $71.01\m^2$/day, and the principal tensor direction is Nl5.39$^{\circ}$E. In BH-4. T(equation omitted) is $268.2 \m^2$/day, $T_{ηη}$ / is $28.75\m^2$/day and the principal tensor direction is N7.55$^{\circ}$E. In BH-5, T(equation omitted) is $168.4\m^2$/day, $T_{ηη}$ is 66.80 $\m^2$/day, and the principal tensor direction is $N76.59^{\circ}$E. On the basis of teleview logging performed on each borehole. the principal fracture directions were revealed as $N0^{\circ}$~4$^{\circ}$E/$30^{\circ}$~$50^{\circ}$SE and $N30^{\circ}$~$80^{\circ}$W/$20^{\circ}$~$50^{\circ}$NE that are the most frequently occurred sets as well as that correspond well with the calculated transmissivity tensor.