• Journal of the Korean Geosynthetics Society
• /
• v.16 no.4
• /
• pp.241-249
• /
• 2017

In a reinforced soil structure, the interaction between soil and an reinforcement occurs due to the frictional resistance on the contact surface between them or the pullout resistance of the reinforcement. Generally, a pullout test is conducted to measure pullout parameters of extensible geogrids. The factors affecting the pullout parameters in a pullout test include a density of backfill, shape of reinforcements, overburden pressure, length of spread reinforcements, and so on. The purpose of this study is to suggest a length of the spreading of an extensible reinforcement that can be used in estimating suitable pullout parameters of a pullout test. To this end, a pullout test was carried out. For the test, the length of spreading of an extensible reinforcement was set as 32 cm, 52 cm, 72 cm, and 100 cm, and effects of the lengths on pullout parameters were analyzed. As a result of the pullout test, it was confirmed that the frictional resistance between the soil and the reinforcement increases with the increase of the length of the reinforcement.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.4
• /
• pp.1699-1705
• /
• 2012

This study was conducted to examine the differences of the quality of chest compression between 10 cm higher position of rescuer's knee from the bottom and its bottom position during implementation of CPR. It selected randomly subjects out of 66 students who attend the Dept. of Emergency Medical Technology in G college, G metropolitan city as the first grader and divided them into 31 experimental group and 32 control group from Nov. 8 to 9, 2011. Mattress was spread 10 cm higher from the bottom(material: B4 Copy Paper) and on the bottom(material: PVC, size: $185{\times}125{\times}0.65cm$) and only chest compression was conducted for 2 minutes. Experiment was conducted with 1 Resusci Anne mannequin and the results of experiment were recorded with Laerdal PC Skill Reporting System. Data collected were analyzed with $x^2$-test and Fisher's exact probability test using SPSS 14.0 for Window, Mann-Whitney U-test, and Wilcoxon signed rank test. As a result of the study, it was found that 10 cm higher position of rescuer knee from the bottom than the bottom position and group below 170 cm in their height and 65 kg in their weight were more effective in proper depth of chest compression and average chest compression depth.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.48 no.6
• /
• pp.436-441
• /
• 1999

Joule heating effect in EM(Electromigration) test were performed on a bend test structure. EM test is done under high current densities(1.0-2.5MA/cm2), which leads to joule heating. Since joule heating is added to the controlled oven(stress) temperature, themetal line temperature is higher than the stress temperature. The increase in the stress temperature due to joule heating is important because EM phenomena and metal line failure are related to the stress temperature. In this paper, metal line was stressed with a current density of 1.0 MA/$cm^2$, 1.5MA/$cm^2$, 2.0MA/$cm^2$, 2.5MA/$cm^2$, for 1200 sec and temperature increase due to joule heating was less than $10^{\circ}C$. Also it took 30 minutes for the metal line to equalized with oven temperature. Recommendations are given for the EM test to determine the initial resistance of EM test structure under stress temperature and current density.

• Journal of Korean Society of Water and Wastewater
• /
• v.10 no.3
• /
• pp.83-91
• /
• 1996

The pulverized wastes originated from kitchen garbage grinder cause an additional load in sewage treatment plant and water environment. Therefore, several problems occur in sewer, such as microbial corrosion, odor, psychoda and fly interrupting flow of sewage etc. by their precipitation with earth and sand. This study was conducted on two experiments: hydrogen sulfide gas generation from sediments in sewer and anaerobic batch test. In anaerobic batch test, gas generation was increased when organic compounds were increased in concentration. Sulfide was decreased upon decreasing in sulfate concentration. In $H_2S$ gas generation test along the depth of sediments there were two different sampling sites which are apart from about 50 cm each other in a menhole. The one has the thickness of 55 cm from the surface, the other, of 60 cm. The hydrogen sulfide gas production rates were measured based on ranges from 0 to 10 cm, 10 to 20 cm, 20 to 30 cm for two samples. The results obtained were 1.08, between 0 to 10 cm in depth for the sample thickness of 55 cm and 3.07, 5.36, $5.42{\mu}g/g-VS{\cdot}hr$ in order of depth for the sample thickness of 60 cm, respectively.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2000.03b
• /
• pp.338-345
• /
• 2000

In this study, applicability of PMT in domestic area and test procedure were studied. At six test holes of three construction sites in Pusan, PMT using Elastometer-200 type was done. The problems during test were investigated and the test results were analysed. Limit pressure, p$\sub$ι/ could be determined by p- Δv/v method. Using PMT results, marine soil in Pusan could be classified approximately. Net limit pressure value was in the range of 6.4 ∼ 22.5 kg/$\textrm{cm}^2$ in clay, 2.2 ∼ 30.0 kg/$\textrm{cm}^2$ in sand, 13.0 ∼ 58.0 kg/$\textrm{cm}^2$ in weathered soil and 47.0 ∼ 190.0 kg/$\textrm{cm}^2$ in weathered rock. Also, E$\sub$m//p$\sub$ι/ value was in the range of 2.4 ∼ 7.0 in clay, 2.6 ∼ 12.1 in sand, 6.8 ∼ 17.1 in weathered soil and 7.2 ∼ 29.6 in weathered rock.

• Journal of the Korean Geosynthetics Society
• /
• v.14 no.4
• /
• pp.45-58
• /
• 2015

Even though the plate bearing test (PBT) to evaluate the load baring capacity and the field density test to evaluate the relative density are mainly used for quality control of soil compaction in Korea, use of the dynamic cone penetrometer test (DCPT) and the dynamic plate bearing test (DPBT) considering economic feasibility, rapidity, and suitability for field conditions increase to use for quality control of soil compaction. In this study, bearing capacity and relative density of subgrade with thickness of 20 cm, 30 cm, and 40 cm are estimated using PBT, DCPT, DPBT and field density test in three field compaction tests, and the relationship among various compaction evaluation methods is analyzed and discussed.

• International Journal of Highway Engineering
• /
• v.4 no.4 s.14
• /
• pp.41-52
• /
• 2002

This study dealt with analysis of size effect of testing apparatus for Kim test which measures rut resistance characteristics of asphalt mixture under static loading. Two columns in different diameter with each column having different radios of round cut (Curvature) at the bottom were used for testing asphalt mixture. Deformation load ($P_{max}$) and deformation strength ($K_D$) were found to have relatively high correlation with rut depth and dynamic stability of asphalt concrete. Diameter of specimen was not a significant factor in this test. From the statistical correlation analysis with rutting properties, the radius of curvature and diameter of loading column were found to be important factor affecting the results of the test. Among the radios (r) of curvatures, r=0.5cm and 1.0cm showed much higher correlation than the column without curvature, and r=1.0cm being better between the two. The column with diameter of 4cm showed better correlation than diameter of 3cm. Therefore, the column of 4cm diameter with r=1.0cm was found to be the best among various apparatus sizes. Prediction models for rut depth and dynamic stability were developed for each aggregate mixture based on Kim test variables using SAS STEPWISE procedure. Therefore, if this test method is validated through further study, Kim test can be used for selecting asphalt mixture with the highest resistance against permanent deformation.

• Journal of the Korean Geosynthetics Society
• /
• v.14 no.4
• /
• pp.117-127
• /
• 2015

Recently, there has been a string of negligent accidents for the retaining wall and slope. In order to measure the ground deformation for the MSE wall, the authors carried out the model test to assess behavioral characteristics of geogrid MSE walls in active failure state with different conditions of geogrid reinforcement. The models are built in the soil container box having dimension, 100 cm long, 90 cm height, and 10 cm wide. The reinforcement used in the model test is geogrid (polyvinyl chloride, PVC). Three geogrids are sized by $30cm{\times}60cm$, $30cm{\times}70cm$, $30cm{\times}80cm$ (width ${\times}$ length) respectively. In this study, the laboratory model tests represented for several conditions of the MSE wall, and then its results were compared to 2D FE analysis.

• Journal of the Korean Society of Costume
• /
• v.51 no.7
• /
• pp.147-165
• /
• 2001

The objective of this study was to develop the Jeogori Pattern for 9 to 10 year-old boys To determine the measurement items for the Jeogori Pattern making, applied factor analysis, correlation analysis and regression analysis to the 37 measurement items of the 9 to 10 year-old boys classified as a standard somatotype. To understand the shape and variation of the body surface, analyzed the replica of the upper body surface that was obtained by the method of using surgical tape. Be based on the results of the above studies, designed the Jeogori Pattern. The designed pattern was evaluated by the sensory test. The drafting methods of Jeogori Pattern obtained are as follows. $\circled1$ The measurement items are Bust Girth, Center Back Waist Length, Neck Width, and Hwajang Length. $\circled2$ Jeogori Length Center Back Waist Length$\times$4/3 $\circled3$ Front Body Girth(1/2) : B/2 + 1.5cm Back Body Girth(1/2) : B/2 + 3.5cm $\circled4$ Jin-Dong : B/4 + 3cm $\circled5$ Back Godae Width(1/2) : Neck Width/2 + 1.7cm Front Godae Width(l/2) : Back Godae Width(1/2) - 2cm $\circled6$Back Godae Point is 1.5cm higher than shoulder line, and Front Godae Point is 1.5cm lower than shoulder line. $\circled7$ Back Godae Depth: 1.2cm + 1.5cm = 2.7cm The Jeogori Pattern designed by the above method Is as (fig. 8) The results of the sensory test of the new pattern are as fellows. Except for 2 items, every mark of 24 test items has over 5.0 point and a total average mark is 5.25 point. Witch is a good mark. Therefore the new pattern is valid. Especially, the parts of Git, sleeves and back face have a high mark, so the appearances of those parts are excellent.

• Journal of Korean Society of Water and Wastewater
• /
• v.13 no.1
• /
• pp.72-80
• /
• 1999

Separation of VOCs(Volatile Organic Compounds) in Water Using Activated Carbon is known to be effective. Activated Carbon has been and will be employed in many water treatment plants. Simplified plug flow homogeneous surface diffusion model(PFHSDM) has been used to predict adsorption of organic matter. Finite Element Method(FEM) was used to analyze the model. Out of water quality control substances, benzene, toluene and tetrachloroethylene were used in the small column test. Film diffusion coefficients and surface diffusion coefficients were obtained from the column test, and were compared with the modeling results. Mc Cune, Williamson, William and Kataoka model, were compared with film diffusion coefficients obtained in the test. McCune model was fitted best for those VOCs used in this experiment. Film diffusion coefficients of VOCs obtained were benzene 0.265 cm/min, toluene 0.348 cm/min and tetrachloroethylene 0.298 cm/min. Surface diffusion coefficients of VOCs obtained were benzene $6.36{\times}10^{-8}cm^2/min$, toluene $3.20{\times}10-8cm2/min$, and tetrachloruethylene $4.94{\times}10^{-8}cm^2/min$.