• Journal of the Korean Geotechnical Society
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• v.22 no.7
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• pp.73-83
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• 2006

The behaviour characteristics of Granular Compaction Pile (GCP) are mainly governed by the lateral confining pressure mobilized in the soft soil matrix to restrain the bulging failure of the granular compaction pile. The GCP method is most effective in soft soil with undrained shear strength ranging $15{\sim}50kPa$. However, the efficiency of this method reduces the more compressible soil conditions, which does not provide sufficient lateral confinement. In the present study, the GCP method reinforced with uniformly graded permeable concrete is suggested for the extension of application to the soft ground. Also, large triaxial compression tests are conducted on composite-reinforced soil samples for verification of availability of the suggested method and the settlement estimation method of the reinforced GCP is proposed. Furthermore, for the verification of the proposed method, predicted settlements by the proposed method are compared with results of 3-dimensional numerical analyses. In addition, parametric studies are performed together with detailed analyses of relevant design parameters.

• 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.

• The Korean Journal of Franchise Management
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• v.8 no.4
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• pp.7-19
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• 2017

Purpose - The purpose of this study is to investigate the effect of model attractiveness on brand attitude and purchase intention, and examine whether product-model match-up plays a moderating role in the relationship between model attractiveness and brand attitude and purchase intention. The model attractiveness is consist of psychological and physical attractiveness of the model. The authors investigate how product-model match-up influence the strength of the relationship between model attractiveness - brand attitude and purchase intention. The purpose of this is to test whether product-model match-up influence the form and effectiveness of a model attractiveness on brand attitude and purchase intention and suggest the effective and efficient methods in the model selection strategies to increase advertising effectiveness based on the results of this study. Research design, data, and methodology - The experimental design for this study was the between subject design based on 2 group of the psychological attractiveness(high vs. low) × product-model match-up(high vs low) and 2 group of the physical attractiveness(high vs. low) × product-model match-up(high vs low). And a preliminary investigation was conducted to develop experimental stimuli through manipulation check to enhance the external validity of experimental research. The attractiveness of the model and product-model match-up are independent variables and manipulative variables in presentation of experimental stimuli. The self-administered methode experiment was conducted on 300 subjects in four groups constructed according to the independent variables. Result - The findings provide partial support for a moderator for product-model match-up on the model attractiveness - brand attitude and purchase intention. First, the influence of psychological attractiveness and physical attractiveness on brand attitude and purchase intention was shown significant. Also, it was found that the average value of brand attitude and purchase intention according to psychological attractiveness was significantly higher than the average value of brand attitude and purchase intention according to physical attractiveness in additional analysis. Second, the average value of brand attitude and purchase intention were higher when product - model match-up was high in both high and low psychological attractiveness and physical attractiveness of the model. However, in the case of psychological attractiveness, the correlation effect with product - model match-up was significant, but in the case of physical attractiveness, it was not significant. Conclusions - The results of this study suggest that the attractiveness factor should be considered in selecting the ad model by verifying the effect of the attractiveness of the model on the advertising effect. In particular, this study has great significance both academically and practically in terms of suggesting such implications that the advertising effect of psychological attractiveness and physical attractiveness may be different depending on the product type by additional analysis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.2
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• pp.25-32
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• 2023

In this study, a double wall system is introduced, which was invented to simplify the complicated manufacturing process of the existing precast concrete (PC) double wall systems and to remove defects such as laitance that may occur during the production of concrete panels. An experimental study was conducted to investigate the tensile resisting capacity of the steel tube which is embedded in the precast concrete panel to keep the spacing between PC panels and to prevent damage of the PC panels during transportation and casting concrete onsite. The experiment was planned to determine the detail of effective steel tube connection considering the steel plate treatment method according to the formation of the opening, the presence of embedded concrete, and the reinforcement welding for additional dowel action as key variables. As a result, the ultimate tensile strength increased by 20-30% compared to the control specimen (ST) except for the steel tube specimen (ST_CP) which has steel plates bent inward at the end part of the steel tube. Since the specimen (ST_CON) filled with concrete inside the control specimen has no additional process and cost for the steel tube connections compared to the control specimen during the production of the developed double wall system, it is determined to be the appropriate detail of steel tube connection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6C
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• pp.321-329
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• 2008

In this study, a series of column test as a way in order to make up for the weakness point of the conventional acceleration method were conducted to both propose the suction board drain method and grapes the specific improvement character of this method as a result of a sort of plastic drain board and a phase of vacuum pressure conditions. On this occasion, the study focused on computing the effective factors of the fittest Suction board drain method affected by each condition through confirming the settlement generated during the test, the water content reduction and stress increase effect occurred arising from the test, and the ratio of consolidation related to the improvement period. In accordance with the shape of core and that whether the core is attached to the filter(pocket or adhesion), the castle type of adhesion and the column type of pocket are more efficient than the others as a consequence of the test to find out the improvement effect depending on each drainage such as a castle type, coil type, harmonica type, column type of pocket and a castle of the adhesion. In case of the step suction pressure, the shorter the period of $-0.8\;kg/cm^2$ as a final step of the suction pressure is, the better the improvement is. In addition, the correlation between degree of consolidation per each suction pressure level and duration of application was drawn as a curve and the point of inflection on this curve was provided to determine the duration period to maximize the consolidation.

• 한국노년학
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• v.29 no.1
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• pp.37-50
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• 2009

The purpose of the present study was to develop a community-based intensive health care program for the community dwelling elderly to strength their functional status and to verify the effect on their geriatric syndrome. A one-group pretest-posttest design was used for the study. A total of 69 frail elderly, who lived in the area within 20 minutes by car, were committed themselves to the day care center(Sangikjae), and had the ability of verbal communication were selected from G city in Kyunggi province. The participants completed a set of questionnaires to measure the sub-score of frailty, fall, urinary incontinence, malnutrition, and mild cognitive disorder domain, using the Otasha-Kensin through the physical examinations and interviews. After 4 weeks of intervention, the outcome was measured to evaluate the effects of the program, and the data obtained were analyzed using descriptive statistics, paired t-test and McNemar test. The results showed that the sub-score of frailty, fall, urinary incontinence, and malnutrition domain were statistically significantly decreased after intervention except those of urinary incontinence and mild cognitive disorder domain, implying that the risk of frailty, fall, and malnutrition was decreased. These findings indicated that community-based the intensive health care program is effective for relieving geriatric syndrome of the community dwelling elderly.

• Earthquakes and Structures
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• v.23 no.4
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• pp.373-384
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• 2022

To improve the seismic performance of suspended ceiling structures, various vibration-damping devices have been developed. However, the devices made of metals have a limit in that they cause large deformation and seriously damages the exterior of the suspended ceiling structure from the wall. As a results, their strengthening effect of the suspended ceiling structure was minimal. Thus, this study employed a spring and vibration-proof rubber effectively controlled vibrations without increasing horizontal seismic loads on the ceiling to enhance the seismic resistance of suspended ceiling structures. The objective of the study is to examine the dynamic properties of a seismic damping-isolation unit (SDI) with various details developed. The developed SDI was composed of a spring, embossed rubbers, and prestressed bolts, which were the main factors enhancing the damping effect. The shaking table tests were performed on eight SDI specimens produced with the number of layers of embossed rubber (n_s), presence or absence of a spring, prestressed force magnitude introduced in bolts (f_ps), and mass weight (W_m) as the main parameters. To identify the enhancement effect of the SDI, the dynamic properties of the control specimen with a conventional hanger bolt were compared to those of the SDI specimens. The SDI specimens were effective in reducing the maximum acceleration (A_{c max}), acceleration amplification factor (α_p), relative displacement (δ_R), and increasing the damping ratio (ξ) when compared to the control specimen. The A_{c max}, α_p, and δ_R of the SDI specimens with two rubbers, spring, and f_ps of 0.1f_by, where f_by is the yielding strength of the screw bolt were 57.8%, 58.0%, and 61.9% lower than those of the conventional hanger bolt specimens, respectively, resulting in the highest ξ (=0.127). In addition, the α_p of the SDI specimens was 50.8% lower than those specified in ASCE 7 and FEMA 356. Consequently, to accurately estimate the α_p of the SDI specimens, a simple model was proposed based on the functions of f_ps, stiffness constant of the spring (K), W_m, and n_s.

• Health Policy and Management
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• v.33 no.3
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• pp.311-324
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• 2023

Background: Long-term care insurance for the elderly has been stably established along with the quantitative expansion of long-term care facilities. Indeed, the need for a paradigm about human rights-based service approach is being raised throughout society from a service perspective. Therefore, this study aimed to analyze the association between elderly human rights awareness and quality of service by considering human rights education as a moderate variable. Methods: This study conducted surveys with 138 caregivers working in long-term care facilities located in Seoul and Gangwon. General characteristics, awareness of human rights, and the level of service quality were examined using descriptive statistics, frequency analysis, and correlation analysis. And multi-variable linear regression with a hierarchical framework was employed. These analyses were performed using IBM SPSS ver. 25.0. Results: Of the 138 caregivers, 97.1% were female, 87.7% were more than 50 years old, and most of their education level was high-school graduates. Their length of employment ranged from more than 5 years to less than 10 years. The level of awareness regarding elderly human rights of the elderly was below normal (mean=2.21), but the quality of service was high (mean=4.21), and the need for human rights education was also high (mean=4.28). Among the general characteristics, the length of employment was significantly associated with awareness of elderly human rights. Moreover, political rights awareness, included as sub-domains of human rights, was positively associated with quality of service. However, the moderating variable, human rights education, was not significantly associated with the quality of service. Conclusion: In this study, human rights education, as a moderating variable, did not have a statistically significant effect on caregivers' human rights awareness in relation to service quality. This finding is inconsistent with previous research results. These results can be explained by the fact that the frequency of education in long-term care facilities was a significant factor in the practice of protecting the human rights of the elderly. Therefore ongoing encouragement for the frequency of current human rights education and improvements in the educational approach appear to be necessary. In addition, these findings reveal the need for strength of education policies and effective in-depth research about human rights and quality of service to respect the human rights of the elderly.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.161-168
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• 2023

Converter slag is a by-product generated by refining the pig iron produced into molten steel in the blast furnace, occupying about 15 % of the weight of steel production. It has a high free-CaO content that can generate expansion cracks when used for concrete aggregate. This is the main reason to make it difficult to recycle. To solve this problem, government guideline requires that converter slag has to be aged in an open yard for 90 days. However, aging can not be perfectly performed because it entails time and cost. In this study, we tried to investigate the applicability of converter slag as a cementitious material rather than an aggregate by mixing converter slag with mortar formulations. According to the EDS results of the converter slag in the experiment, we found that screening in the aggregate phase was more effective than that in the powder phase. When the particles separated by a magnet in the aggregate state were pulverized and used for concrete up to a 15 % replacement ratio, various engineering characteristics, such as flow, length change, and compressive strength, showed engineering characteristics similar to those of the control mix.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.51-60
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• 2023

Purpose : The purpose of this study was to determine the effect of pelvic floor muscle exercise (PFME) on an unstable support surface on maximal inspiratory pressure (MIP), maximum expiratory pressure (MEP), and abdominal muscle thickness as a method for effective PFME. Methods : This study was performed on 22 subjects. They were matched and divided into two groups based on body mass index; the experimental group (EG) performed PFME on a foam roller (n= 11), the control group (CG) performed PFME on a stable support surface (n= 11). Kegel exercise was performed with 10 seconds of contraction, 10 seconds of relaxation, and 4 sets of 10 reps per set. Both of group executed the exercise 3 times a week for 2 weeks. MIP and MEP was measured using a spirometer. Abdominal muscle thickness was measured using ultrasound. The paired t-test was used to compare difference on each group and the comparison between groups was analyzed using the independent t-test. A significance level of α= .05 was used to verify statistical significance. Results : The EG showed a significant increase in the MEP (p<.05). The CG showed a significant increase in the MEP (p<.05). There was no significant difference in the two groups (p>.05). The EG showed a significant increase in the external oblique, internal oblique and transverse abdominis (p<.05). The CG showed a significant increase in the internal oblique (p<.05). There was no significant difference in the two groups (p>.05). Conclusion : Based on the results of this study, additional research should be conducted to correct the limitations of this study to confirm that PFME performed on a foam roller has a positive effect on respiratory muscle strength and abdominal muscle thickness.