• Journal of the Korean Geotechnical Society
• /
• v.23 no.3
• /
• pp.61-75
• /
• 2007

Deep foundations have been popularly installed in hard stratum such as gravels or rocks in Korea. However, it is necessary to consider sand or sandy gravel layers that locate at the mid-depths as the bearing stratum of piles in the thick Nakdong River deltaic deposits, as done in the Chaophraya (Bangkok) and Mississippi River deltas. This study was focused on the finding of suitable methods for estimating bearing capacity when driving prestressed high-strength concrete (PHC) piles to a required depth in the deltaic area. Ground investigation was performed at five locations of two sites in the deltaic area. Bearing capacity of the driven piles has been computed using a number of proposed methods such as CPT-based and other analytical methods, based on the ground investigation and comparison one another other. Five PDA (pile driving analyzer) tests were systematically carried out at the whole depths of embedded piles, which is a well-blown useful technique for the purposes. As the results, the bearing capacities calculated by various methods were compared with the PDA and static load testing results. It was found that the shaft resistance is significantly governed by set-up effects and then the long-term value agrees well with that of the $\beta$ method. Also, the design methods for toe resistance were determined based on the SLT result, rather than PDA results that led to underestimation. Moreover, using the CPT results, appropriate methods were proposed for calculating the bearing capacity of the piles in the area.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.51 no.5
• /
• pp.1-12
• /
• 2023

This study evaluated the overturning stability of portable tripod ladders used for high-altitude work such as tree management and pruning work in landscaping construction and management. Portable tripod ladders, which are included in general mobile or portable ladders frequently used in industrial sites, are supported in a triangular support structure, not a 4-point support like common A-type Ladders. In addition, since the working height is more than twice that of a mobile or portable ladder, the possibility of an overturning accident that threatens the safety of workers with a fall accident is high. Therefore, based on the overturning stability test specified in ANSI-ASC A14.7 and EN 131-Part 7, which are related standards for about 130 types of portable tripod ladders sold and used in Korea. An equation to calculate each moment according to working height was derived. Then, each calculated moment was compared to evaluate the safety factor for overturning and stability. As a result of the overturning stability evaluation according to each standard, when the provisions of EN 131-Part 7 were applied, portable tripod ladders with 8 steps in the rear direction and 6 steps or more in the side direction were evaluated as unstable against overturning, but according to ANSI-ASC A14.7 regulations. It was evaluated that the stability against overturning was secured in all directions and number of steps.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.52 no.3
• /
• pp.76-88
• /
• 2024

A significant cause of fall or overturning accidents in the construction industry, including landscaping construction and management, is work at heights using portable ladders. Portable ladders are classified as A-type or triangular support ladders depending on the number of supporting leg and support conditions. The tripod mobile ladder, which supports itself with only three supporting legs, is unstable and more prone to overturning compared to the A type ladders. Therefore, using the specifications of the tripod mobile ladder and the stability regulations of EN131-Part 7, overturning and resistance moment calculation formulas were derived for all directions in which overturning could occur. The moments calculated using these equations, and the overturning stability in each direction were evaluated. According to the calculation results, although there are differences depending on the direction, most are unstable for overturning at 8 or more steps. Based on these results, this study proposed measures to increase the moment of resistance by changing the weight, depth, and width, and using outriggers to ensure stability against the overturning of ladder. However, when changing the specifications of these measures, the size increases are excessive and the applicability is insufficient. On the other hand, outriggers are an applicable measure as they can ensure stability against overturning with only a minimum expansion length.

• Journal of Digital Convergence
• /
• v.13 no.11
• /
• pp.365-371
• /
• 2015

This experimental research explores the effect of the movie that can be classified as non-news media on viewers' political and social attitude on the theoretical basis of priming effect, focused on the movie 'cart' that deals with non-regular workers' labor movement. For this experimental research, one group of subjects composed of university students were exposed to movie 'cart', and the other not to the movie. After watching a movie, each group of subjects responded to questions that are designed to measure the seriousness of non-regular workers' problem, the necessity of labor movement, support of opposition party, support of the current government. This research found that subjects exposed to the movie 'cart' consider non-regular workers' problem more serious and supports opposition party more positively than subjects not exposed to movie 'cart.' However hypotheses that expected the positive support of treated subjects on labor union and less positive support of treated subjects on current government were rejected.

• Journal of Digital Convergence
• /
• v.16 no.5
• /
• pp.373-383
• /
• 2018

The purpose of this study was to identify menopausal resilience in middle-aged women. The data were collected from 227 middle-aged women who participated in friendship and religious activities in the Jeonbuk province. The data were collected through self-report questionnaires, which were constructed to Self-efficacy, family support, social support, menopausal adaptation, resilience. Data were analyzed using frequencies, means, $X^2$_Test, pearson's correlation coefficient and multiple regression with SPSS/WIN 23. Regular exercise(${\beta}=-.15$, p<.01), self-efficacy(${\beta}=.29$, p=<.001), social support(${\beta}=.29$, p=<.001), menopausal Adaptation(${\beta}=.17$, p<.01) were influencing factors and these variables showed an explanatory power of 35.3% (F=18.65, p<.001). Therefore, it is suggested that middle-aged women in menopause can plan to overcome the menopausal crisis positively through nursing interventions that include self-efficacy and social support.

• Journal of agricultural medicine and community health
• /
• v.43 no.1
• /
• pp.31-40
• /
• 2018

Objectives: The purpose of this study is to examine the moderating effect of social supports on the relationship between grief level and suicidal ideation of the elderly living alone. Methods: We analyzed data from a questionnaire administered to subjects aged 65 years or older living alone for a 2017 community mental health project in Gyeongnam S city. To investigate the moderating effects of variables, we conducted a hierarchial regression analysis and confirmed the change $R^2$. Results: When adjusted for education and economic level, grief level had not a direct impact on suicidal ideation. And it was found that interdependent social support was moderating variables in the relationship of grief level and suicidal ideation of the elderly living alone. Conclusions: There is a need for appropriate programs that reduce suicidal ideation and therefore suicidal action. Moreover, it is especially necessary to enhance interdependent social supports.

• Korean Journal of Social Welfare
• /
• v.65 no.4
• /
• pp.367-393
• /
• 2013

Quality of life(QoL) of older cancer patients have not gained enough attention from researchers even when cancer is the number one cause of death of Korean elderly. Therefore, this study aims at understanding the QoL of older cancer patients and factors related to it, applying Taylor(2012)'s Stress-Coping Process model, and by comparing with older chronic disease patients and middle-aged cancer patients. Results indicated that physical health QoL of older cancer patients was the worst and their mental health QoL was similar with middle aged cancer patients. Multi-group analysis of Structural Equation Modeling indicated that the relation between QoL and the stress coping resources was not statistically different from older cancer patients and older chronic disease group, as well older cancer patients and middle-aged cancer patients. Implications of results to improve the QoL of older cancer patients are discussed.

• Membrane Journal
• /
• v.11 no.2
• /
• pp.83-88
• /
• 2001

A methodology for enhancing the bond strength of a coating layer with a support has been established in preparing low-pressure reverse osmosis mO) hollow fiber which would experience shear badly in flowing feed un it. Prior to coating process, the support membrane, ultrafiltratiun polysulfone(PS) hollow fibers was pretreated with a reaction solution containing glutaraldehyde (GAl which has a good affinity to the suppurt membrane material as well as a reactivity to some of the cunstituents of cuating layer subsequently formed on the support by interfacial polymerization. Therefore, the reactant GA distributed unifonnly over the support layer through the pretreatment could provide a strong adhesive bond between the coating layer and the support, sticking fast to the support membrane through physical bond and, at the same time, connecting its functional group with the coating laycr by chemical bonding. Due to the strong adhesive bond, the resulting hollow fiber membrane showed an excellent long-tcnn stability in pcnneation.

• Membrane Journal
• /
• v.23 no.3
• /
• pp.251-256
• /
• 2013

In this study, acetylated methyl cellulose (AMC) was successfully used as a support layer of thin film composite (TFC) forward osmosis (FO) membrane. A selective polyamide active layer, interfacially polymerized, was coated on top of various substrate layers. The structure and performance of the TFC FO membrane based on the AMC substrate were compared with those of TFC FO membranes with different polymeric support layers. The experimental results showed that the AMC FO membrane performance was better than other FO membranes due to its characteristic morphology and lower back diffusion rate of salts.

• Korean Chemical Engineering Research
• /
• v.47 no.4
• /
• pp.395-402
• /
• 2009

The atomic force microscopy(AFM) has been used, as a powerful tool, to investigate physical properties of supported-lipid layers. Prior to the advent of the AFM, no observation was performed for the physical phenomena at the nanometer-scale. This microscope provides nanometer-scale morphology by scanning surfaces with the cantilever and presents force curve by monitoring the behavior of the cantilever that approaches to surface and retracts from the surface. From the morphology, the structures of the supported lipid layer and the effect of other molecules on the structures have been investigated. From the force curve, the surface properties-electrostatic and mechanical properties-of the supported lipid layers have been studied. In this article, characterization of the structure and surface properties of the supported lipid layer is explained. Future perspectives and direction are also discussed.