• Geomechanics and Engineering
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• v.16 no.6
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• pp.589-597
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• 2018

Centrifuge model tests were used to simulate pile-raft composite foundation and pile-geogrid composite foundation with different pile spacing for researching the time effect of negative skin friction of rigid piles in high-speed railways. The research results show that the negative skin friction has a significant impact on the bearing capacity of composite foundation. Pile-raft composite foundation has higher bearing capacity compared to pile-geogrid composite foundation to reduce the effect of negative skin friction on piles. Both the foundation settlement and negative skin friction have significant time effect. The distribution of skin friction can be simplified as a triangle along the pile. The neutral point position moves deeper in the postconstruction stage at larger pile spacing. For pile-geogrid composite foundation, the setting of pile-cap affects the position of neutral point in the post-construction stage. Reinforced cushion with geotextile may promote the better performance of cushion for transmitting the loads to piles and surrounding soils. Arching effect in the cushion of the composite foundation is a progressive process. The compression of the rigid piles contributes less than 20% to 25% of the total settlement while the penetration of the piles and the compression of the bearing stratum below the pile tips contribute more than 70% of the total settlement. Some effective measures to reduce the settlement of soils need to be taken into consideration to improve the bearing capacity of pile foundation.

• Journal of the Korean Geotechnical Society
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• v.22 no.10
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• pp.47-54
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• 2006

H-pile can be more easily driven than pipe pile by pile driver and shows high skin friction and plugging effect. This experimental study was devoted to investigate skin friction of H group piles in granite soil under laboratory test. Pile arrangements $(1{\times}2,\;1{\times}3,\;2{\times}2,\;2{\times}3,\;3{\times}3)$, pile space (2D,4D,6D), and soil density $(D_r=40%,\;80%)$ were tested. The main results obtained from the model tests can be summarized as follows. Distribution ratio of skin friction for total load decreased by $48{\sim}39%$ (dense soil), $32{sim}27%$ (loose soil) as piles space ratio increases in case of $3{\times}3$ group piles. And the distribution ratio of skin friction by pile settlements under loose soil decreased by about $58{\sim}33.2%$ in $2{\times}2$ group piles and about $65{\sim}38%$ in $3{\times}3$ group piles respectively.

• Journal of the Korean Geotechnical Society
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• v.39 no.6
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• pp.21-30
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• 2023

One of the methods for calculating unit skin friction of soft-rock-socket parts for cast-in-place piles involves the roughness measurement of the parts. The measurements are conducted during the excavation stage. A roughness measuring device is installed in the excavation hole and the unit skin friction is calculated from the measured surface roughness of the rock socket. Herein, the results of roughness measurement of rock-socket parts in cast-in-place piles and that of load transfer tests are analyzed and compared. The unit skin friction from the roughness measurements can be converted into unit skin friction corresponding to the displacement of a pile generated in a load transfer test. A reduction factor is given as R_f = -0.14n + 1.48.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.7189-7193
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• 2015

Background: Cancer is a leading cause of death throughout the world. Increasing life expectancy and aging population are important factors for increasing cancer incidences in developing countries. National programs are essential for prevention and control of cancer in any society. This study aimed to investigate cancer epidemiology and trends in the province of Hamadan, located in Northwest Iran. Materials and Methods: This analytical study was carried out based on cancer registry data from 2004 to 2009 in the province of Hamadan, analyzed using STATA (version 12) software for descriptive tests and Join point 4.1.1.1 software for analytical tests. Results: There were 7,767 registered cases of cancer during the 6 years studied. Of the total cases registered, 59.1% (4,592 cases) involved men and 40.9% (3,175 cases) occurred in women. Age-standardized incidence rates (ASR) increased from 72.9 to 132.0 in males and 48.2 to 115.0 in females during the 6 years of the study (p<0.001). The most common cancers were skin, stomach, breast, bladder, and leukemia. In women, teh most common were breast, skin, stomach, colorectal, and leukemia, in that order, and in men skin, stomach, bladder, leukemia, and prostate cancers. Conclusions: The cancer incidence is greater in men that women in this region but with increasing trends in both sexes. Planning regarding education in prevention of exposure to risk factors and control strategies is required to decrease the incident cases. Screening programs for common cancers in older age groups might be helpful to reduce the disease impact.

• Earthquakes and Structures
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• v.14 no.3
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• pp.249-259
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• 2018

This paper aims to assess the seismic risk of a plane moment-resisting frames (MRFs) consisting of concrete-filled double skin steel tube (CFDST) columns and I-section steel beams. Firstly, three typical limit performance levels of CFDST structures are determined in accordance with the cyclic tests of seven CFDST joint specimens with 1/2-scaled and the limits stipulated in FEMA 356. Then, finite element (FE) models of the test specimens are built by considering with material degradation, nonlinear behavior of beam-column connections and panel zones. The mechanical behavior of the concrete material are modeled in compression stressed condition in trip-direction based on unified strength theory, and such numerical model were verified by tests. Besides, numerical models on 3, 6 and 9-story CFDST frames are established. Furthermore, the seismic responses of these models to earthquake excitations are investigated using nonlinear time-history analyses (NTHA), and the limits capacities are determined from incremental dynamic analyses (IDA). In addition, fragility curves are developed for these models associated with 10%/50yr and 2%/50yr events as defined in SAC project for the region on Los Angeles in the Unite State. Lastly, the annual probabilities of each limits and the collapse probabilities in 50 years for these models are calculated and compared. Such results provide risk information for the CFDST-MRFs based on the probabilistic risk assessment method.

• The Journal of the Korea Contents Association
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• v.8 no.8
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• pp.111-118
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• 2008

Nowadays, people get images from various media like TV, magazines, newspaper, internet. Such images directly influence people's thoughts and lives, either consciously or unconsciously. In the past, reproduction devices have been mainly used in reproducing an original scene accurately. Lately, the cognitive preference became a key value in the scene reproduction, and it was affected by the surrounding media. Recently, the most commonly used device in reproducing an original scene is the camera. The core of an image is the light, in other words, the exposure. Most digital cameras are set to adjust exposure automatically in order to reproduce a scene physically as identical as possible. However, physically right exposure does not always give images that people prefers. Numbers of tests were done to find the exposure value that makes an image cognitively more preferred. Skin tones which are highly sensitive to color and changes in density has been used in the tests. A male and a female model have been used to classify changes in cognitive preference due to gender differences.

• Journal of Convergence for Information Technology
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• v.10 no.7
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• pp.240-248
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• 2020

This study compares and analyzes the tasks and evaluation methods of national technically qualified Skin Esthetic through systematic literature review of prior studies on qualification tests for Skin Esthetic qualification and process evaluation types that have been reorganized based on NCS. The national technical qualification is based on the ability to work through memorization-oriented theoretical tests and simple repetition of functions, and the Qualified qualification is relatively short in the period of test execution, and the reliability of its internal evaluation at the enforcement agency continues to be reduced. In the future, national technical qualification require innovation in the qualification system to reflect skilled demand at industrial sites, and course-based qualification for require supplementation and improvement of education and training courses so that they can learn skilled skills at the site.

• The Journal of Korean Medicine
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• v.30 no.1
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• pp.83-94
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• 2009

Background and Objectives: The skin barrier protects skin against a harmful environment. Its function includes an antimicrobial barrier as well as a physical barrier. Stress is harmful to the skin barrier and there are many studies on this, but there are few about the effect of stress during pregnancy on the skin barrier of offspring. The aim of this study was to investigate the effect of stress during pregnancy on the skin barrier of offspring by examination with the naked eye, cortisol, weight, TEWL and histologic tests. Materials and Methods: Male hairless mice ten weeks old were coupled with females for three days. After twelve days the females were divided into two groups. We stressed one group and not the other group. The offspring from the non-stressed (N group) and stressed (S group) grew up until four weeks. The S group was exposed to chronic mild stress using the chronic stress model protocol modified method of Wilner and Towell for a week. We made examinations with the naked eye, assessment of cortisol, weight, TEWL, and histologic test to contrast the S group with the N group. Statistical analysis was performed by using Mann-Whitney and Friedman test. Statistical significance was achieved if the probability was less than 5% (p<0.05). Results: 1. By making an examination with the naked eye, S group showed papules, creases and dryness on their skin, but N showed no change compared with normal skin. 2. There was no statistically significant difference between S group and N group in cortisol (p>0.05). 3. There was no statistically significant difference between S group and N group in weight. N group had less weight than S group (p<0.05). 4. There was no statistically significant difference between S group and N group in TEWL (p>0.05). 5. There was no statistically significant difference between S group and N group in TEWL recovery (p>0.05). 6. In TEWL and TEWL recovery, there was statistically significant difference by time between S group and N group (p<0.005). Histologically, S group showed a thicker epidermis and epidermal crest than N group. Conclusions: We found that stress during pregnancy has negative effects on the skin barrier of offspring. Though there were no statistically significant differences between S group and N group in TEWL recovery, we found evidence that the recovery of skin barrier function is interrupted by stress during pregnancy by examination with both the naked eye and histology.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.4 no.2
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• pp.319-336
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• 1997

This study was done to identify the reality in doing the intradermal skin test of injectional antibiotics and to serve a basis to the clinical and educational situations. For the study, the survey was done to the staff nurses who are working at one of the selected 39 hospitals in the capital area, from January 6 to Feburary 8 in 1997. The data analysis was done by mean, standard deviation, Fisher's exact test, t-test, ANOVA through running SAS computer program. The results of the study were as follows : 1. The dilution ratio of the antibiotics was mostly 1 : 10 regardless of what kind of antibitics. Making the contrast was done only for the suspended to the antibiotics. Mostly the reaction was detected after 15 to 20 minutes from its diameter of redness and wheals. Most of the respondents answered they do the intradermal skin test only once for the same antibiotics. 2. In the education on the skin test the 66.7% from the respondents had exposed to the education mostly through the new nurses orientation. The 85,4% from them answered the need of the continuous education which had a significant difference in the number of beds(p=.046). The had experiences of detecting positive reactions(98.3%), and of anaphylaxis(49.5%) which had a significant difference in experience(p=.002) and in their age groups(p=.000). 3. The averge score of the confidence on the intradermal skin test was 3.32 form 4-point scale. Also it had a significant difference from the number of beds(p=.010), the year of experiences(p=.016), and their age groups(p=.046). 4. From the general characteristics of respondents, the injection methods had a significant difference in the amounts of injection, whether adopting the contrast pairing, and the repeatable skin tests for the same antibiotics. 5. Only 15 from 39 hospitals had their protocol about the intradermal skin test provided by nursing department which differs in its contents from that provided by the medical information center. From the results of the study, it is suggested that the continuous education on the intradermal skin test and its unified protocol should be provided. Also it is recomended that the drug manufacturer should notice about its anaphylactic cautions and pack its extra skin test use.

• Journal of the Korean Geotechnical Society
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• v.38 no.3
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• pp.5-16
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• 2022

Ground in extremely cold and hot regions can sink by various environmental factors. Ground settlement can generate the negative skin friction to pile shaft, increase the base load of pile, and cut the stability of the pile. This study proposed a member responding ground deformation which can be inserted inside the pile. The member slightly compresses according to the ground settlement to reduce the negative skin friction. As the member materials, this study considered spring and spring-dashpot. To assess the ability of the member, the present research performed model tests for piles with or without the member within settled ground. In the model tests, the base load, total shaft resistance, and horizontal earth pressure were monitored and analyzed. Experimental results show that the pile with spring member can reduce the negative skin friction under small settlement conditions whereas it acts similar to the pile without the member under large settlement conditions as the spring was no longer compressed. However, the pile with the spring-dashpot member can reduce the negative skin friction continuously upon the ground settlement as the dashpot delays the load transfer to the spring and locates friction force on the unloading path.