• The Journal of Engineering Geology
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• v.33 no.2
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• pp.307-322
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• 2023

Rock-mass grouting plays a crucial role in the construction of dams and deep caverns, effectively preventing seepage in the foundations, enhancing stability, and mitigating hazards. Most rock grouting is affected by hydrogeological and rock engineering indices such as rock quality designation (RQD), rock mass quality (Q-value), geological strength index (GSI), joint spacing (Js), joint aperture (Ap), lugeon value (Lu), secondary permeability index (SPI), and coefficient of permeability (K). Therefore, accurate geological analysis of basic rock properties and guidelines for grouting construction are essential for ensuring safe and effective grouting design and construction. Such analysis has been applied in dam construction sites, with a particular focus on the geological characteristics of bedrock and the development of prediction methods for grout take. In South Korea, many studies have focused on grout injection materials and construction management techniques. However, there is a notable lack of research on the analysis of hydrogeological and rock engineering information for rock masses, which are essential for the development of appropriate rock grouting plans. This paper reviews the current state of research into the correlation between the grout take with important hydrogeological and rock engineering indices. Based on these findings, future directions for the development of rock grouting research in South Korea are discussed.

• Tunnel and Underground Space
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• v.33 no.6
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• pp.574-593
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• 2023

In this study, the effectiveness and applicability of a newly designed Compact CNS shear box for conducting direct shear tests on jointed rock specimens were investigated. CNS joint shear tests were conducted on jointed rocks with Artificially generated roughness while varying the fracture surface roughness coefficient and initial normal stress conditions. In addition, displacement data were validated by Digital image correlation analysis, fracture patterns were observed, and comparative analysis was conducted with previously studied shear behavior prediction models. Furthermore, the accuracy of the displacement data was confirmed through DIC analysis, the fracture patterns were observed, and the shear properties obtained from the tests were compared with existing models that predict shear behavior. The findings exhibited a strong correlation with specific established empirical models for predicting shear behavior. Furthermore, the potential linkage between the characteristics of shear behavior and fracture patterns was deliberated. In conclusion, the CNS shear box was shown to be applicable and effective in providing data on the shear characteristics of the joint.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.6
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• pp.45-52
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• 2019

Steel corrosion due to carbonation in RC (Reinforced Concrete) structures easily occurs in urban cities with high CO₂ concentration. RC structures are always subjected to external loading with various boundary conditions. The induced stress level causes changes in diffusion of harmful ion like CO₂. In this work, a quantification of carbonation progress with stress level is carried out and carbonation prediction is derived through the relations. Determining the design parameters like cover depth, CO₂ diffusion coefficient, carbonatable materials, and exterior CO₂ concentration as random variables, service lifes under carbonation with design parameter's variation are obtained through MCS(Monte Carlo Simulation). Additionally the service life with different stress level is derived and the results are compared with those from deterministic method. Cover depth and cement hydrates are evaluated to be very effective to resist carbonation, and the proposed method which can consider the effect of stress on service life can be applied to maintenance priority determination.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.185-193
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• 2012

In this study, an estimation equation was proposed to predict the shear strength of RC interior beam-column connections. The proposed equation considered the effect of both truss and arch mechanisms, while the existing equations in the ACI and AIJ design codes consider only arch mechanism. In addition, the proposed equation estimates the shear strength of RC joints by considering the contribution of the vertical and horizontal steel bars on the effective compressive strength of concrete. The shear strength of RC joints calculated by the proposed equation was compared with the test results of 54 RC joints, which failed in shear before plastic hinges developed at the end of the adjacent beams. The comparison study showed that the proposed equation estimated the strength of the 54 specimens with a mean value of 1.14 and the coefficient of variation of 20%. The proposed equation provides improved prediction compared to those obtained from the equations in the ACI and AIJ design codes.

• Journal of muscle and joint health
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• v.6 no.2
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• pp.211-225
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• 1999

This descriptive correlational study was carried to identify the relationship among social support, compliance, and psychosocial adjustment of patients with rheumatoid arthritis. The study was done with 100 rheumatoid arthritic patients who were visited in Outpatient clinic of university hospital in Taegu, Korea from the 23rd of February to the 20th of March in 1998. The Data were collected through person to person interviews which were performed by five researchers. The instruments used for this study were Yu's social support scale(1996), Cho's compliance scale(1987), and Kim's psychosocial adjustment scale(1997). The data was analyzed by using a t-test, Pearson correlation coefficient, ANOVA, and Tukey test with the SAS Program. The results of this study were as follows ; 1. The mean score of social support was 2.76 for 4 full marks, compliance was 3.20 for 5 full marks, and psychosocial adjustment was 2.26 for 4 full marks. 2. Hypothesis 1 : "The higher the social support degree, the higher the compliance degree of the rheumatoid arthritis patient". It was supported(r=0.54, p<0.001). Hypothesis 2 : "The higher the compliance degree, the higher the psychosocial adjustment degree of the rheumatoid arthritis patient". It was supported(r=0.34, p<0.001). Hypothesis 3 : "The higher the social support degree, the higher the psychosocial adjustment degree of the rheumatoid arthritis patient". It was supported(r=0.24, p<0.05). 3. In general, the spouse group compared to other groups was demonstrated as the most dependable group for patients to trust and expect support. And the sons and daughters group was shown higher than other groups in terms of social support(F=4.19, p=0.01). There was no difference in terms of compliance in degree. In the degree of psychosocial adjustment the highly educated group(more than high school) is a little higher than the lowly educated group(F=3.08, p=0.03). In the costs of medical care, the group that could afford was significant higher than the group which could not afford results in terms of the psychosocial adjustment degree(F=3.99, p=0.01). The outcome of this study is that the social support that related rheumatoid arthritic patients had an effect on the following compliance, and the following compliance helps psychosocial adjustment of patients. It also shows that social support related psychosocial adjustment. Therefore, to increase the level of psychosocial adjustment of rheumatoid arthritic patients, it will be effective in supportive nursing intervention to improve social support and compliance.

• Journal of muscle and joint health
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• v.3 no.1
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• pp.63-89
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• 1996

This study has been done for the purpose of determining whether the positive association between social support and depression is attributable to an overall beneficial effect of support(direct effect) or to a process of support protecting persons from adverse effects of stressors such as life events, pain or physical disability (buffering effect). The sample consisted of 214 patients who were identified as the rheumatoid arthritis. The instruments used in this study were Depression Scale(CES-D), Perceived Social Support Scale, Life Events Questionnaire, AIMS Pain Scale, and Physical Disability Scale. The data were analysed by the use of t-test, ANOVA, Pearson Correlation Coefficient and Stepwise Multiple Regression. The results of this study are summerized as follows : 1. The 1st hypothesis, "The higher the life events degree, the higher the depression degree" was supported(r=.49, P=.0001). 2. The 2nd hypothesis, "The higher the pain degree, the higher the depression degree" was supported(r=.44, P=.0001). 3. The 3rd hypothesis, "The higher the physical disability degree, the higher the depression degree" was supported (r=.46, P=.0001). 4. The 4th hypothesis, "The higher the social support degree, the lower the depression degree" was supported(F=84.52, P=.0001). 5. The 5th hypothesis, "There will be different in the relationship between the degrees of life events and depression according to social support degree" was rejected (F=.29, P=.5928). 6. The 6th hypothesis, "There will be different in the relationship between the degrees of pain and depression according to social support degree" was supported (F=3.19, P=.0755). 7. The 7th hypothesis, "There will be different in the relationship between the degrees of physical disability and depression according to social support degree" was supported(F=5.69, P=.018). 8. The predictive variables for depression were the degrees for social support, life events, pain, and physical disability. 9. The depression degree showed a inverse correlation with social support degree (r=-.56, p=.0001). The social support degree showed a inverse correlation with the degrees of life events(r=-.22, p=.0007), pain(r=-.18, p=.0069) and physical disability(r=-.15, p=.0293). 10. The depression degree showed significant differences in the variables of sex (t=2.26, p=.025), educational level(r=.189, P=.006) and the number of treatment method (r=.201, P=.003). In conclusion, it was found that social support had the direct effect on depression and the buffering effect in each relationship between degrees of pain or physical disability and depression in patients with rheumatoid arthritis. So the researcher thinks that it is effective that nurses should provide these patients with social support to reduce depression in cases of having severe pain or physical disability.

• Spatial Information Research
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• v.11 no.2
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• pp.101-117
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• 2003

High resolution satellite image analysis has been recognized as an effective technique for monitoring local land-cover and atmospheric changes. In this study, a new high resolution map for land-cover was generated using both high-resolution IKONOS image and conventional land-use mapping. Fuzzy classification method was applied to classify land-cover, with minimum operator used as a tool for joint membership functions. In separateness analysis, the values were not great for all bands due to discrepancies in spectral reflectance by seasonal variation. The land-cover map generated in this study revealed that conifer forests and farm land in the ground and tidal flat and beach in the ocean were highly changeable. The kappa coefficient was 0.94% and the overall accuracy of classification was 95.0%, thus suggesting a overall high classification accuracy. Accuracy of classification in each class was generally over 90%, whereas low classification accuracy was obtained for classes of mixed forest, river and reservoir. This may be a result of the changes in classification, e.g. reclassification of paddy field as water area after water storage or mixed use of several classification class due to similar spectral patterns. Seasonal factors should be considered to achieve higher accuracy in classification class. In conclusion, firstly, IKONOS image are used to generated a new improved high resolution land-cover map. Secondly, IKONOS image could serve as useful complementary data for decision making when combined with GIS spatial data to produce land-use map.

• Journal of the Microelectronics and Packaging Society
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• v.30 no.3
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• pp.40-50
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• 2023

Recently, the number of components of smartphones increases rapidly, while the PCB size continuously decreases. Therefore, 3D technology with a stacked PCB has been developed to improve component density in smartphone. For the s tacked PCB, it i s very important to obtain solder bonding quality between PCBs. We investigated the effects of the properties, thickness, and number of layers of interposer PCB and sub PCB on warpage of PCB through experimental and numerical analysis to improve the reliability of the stacked PCB. The warpage of the interposer PCB decreased as the thermal expansion coefficient (CTE) of the prepreg decreased, and decreased as the glass transition temperature (Tg) increased. However, if temperature is 240℃ or higher, the reduction of warpage is not large. As FR-5 was applied, the warpage decreased more compared to FR-4, and the higher the number and thickness of the prepreg, the lower the warpage. For sub PCB, the CTE was more important for warpage than Tg of the prepreg, and increase in prepreg thickness was more effective in reducing the warpage. The shear tests indicated that the dummy pad design increased bonding strength. The tumble tests indicated that crack occurrence rate was greatly reduced with the dummy pad.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.2 no.1
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• pp.67-85
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• 1995

The purpose of this study was to determine the effects of rhythmic movement therapy for adaptation state in mastectomy patients. The quasi-experimental study was designed using nonequivalent control group pretest-posttest design within the framework of Laszarus & Folkman's stress-adaptation model. The subjects of the study were composed thirty-two mastectomy patients, of these fifteen were assigned to the experimental group and seventeen to the control group. Rhythmic movement therapy was carried out twice a week for thirty-five, minutes or forty minutes for six weeks period from August 22 to September 30 in 1994. Data was collected before and after the experimentation. Collected data was analyzed by mens of chi-square test, t-test, two-way ANOVA, Pearson's correlation coefficient with $SPSS/PC^+$. The results were summarized as follows : 1. Physical symptom score in the experimental group and control group was not significant difference. 2. Joint Movement Parameter in the experimental group and control group was significant difference. 3. Depression score in the experimental group and contrl group was significant difference. 4. Body image score in the experimental group and control group was significant difference. 5. Stress perception score in the experimental group and control group was significant difference. 6. Social adjustment score in the experimental group and control group was significant difference. 7. Each adaptational level in the experimental group and control group according to type of Health Locus of Control were partially significant difference. Depression score and social adjustment score between the experimental group and control group according to others Health Locus of control were significant difference. This data suggest that rhythmic movement therapy was more effective in the group of Others health Locus of Control. 8. Each adaptational level between the experimental group and control group according to amount of spouse support were not significant difference. 9. The significant positive correlation between physical symptom score and body image, between body image and social adjustment, were observed. The significant negative correlation between stress perception score and social adjustment, between depression and body image, between depression and social adjustment, were observed. This data suggest that the more physical symptom score increased, the more body image increased and the more body image, the more social adjustment. And then the more stress perception score decreased, the more social adjustment increasded and the more depression score, the more body image and social adjustment. Thus it is concluded that the rhythmic movement therapy was a useful nursing intervention for adaptation of mastectomy patients.