• Journal of Ocean Engineering and Technology
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• v.28 no.4
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• pp.268-273
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• 2014

To investigate the turbulence characteristics within the boundary layer over a flat plate, an experimental study was performed using a PIV technique in a circular water channel. For two water velocities, 0.92 and 1.99 m/s, the water velocity profiles were taken and analyzed to determine turbulent characteristics such as the Reynolds stress, Taylor micro-length scale, and Kolmogorov length scale within the defect law region of the boundary layer. These analysis methods may be applied to research on the friction drag reduction technology using micro-bubbles or an air sheet over the surface of a ship's hull, because the physical reason for the friction drag reduction could be found by understanding the variation of the turbulence characteristics and structures in the boundary layer.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.2
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• pp.277-288
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• 2003

The purpose of this study was to provide information on how to improve the current sizing system of infant coveralls through analysis of the present system. In order to compile the information about dissatisfaction with the appropriateness of the fit of infant coveralls, a questionnaire was administered to mothers of 241 infants (aged under 36 months) living in Seoul, and analyzed using the SPSS WIN.10.0 program. Also, the manufacturers'basic body sizes were investigated. The results of this study were as follows : 1. The results of the comparison between the manufacturers'basic body sizes and the body measurement values obtained as the physical standard of the nation(1997) show that in terms of length and hip circumference, the manufacturers'body sizes were larger. On the other hand, in the waist circumference, the manufacturers'body sizes were smaller than the national average. 2. Research on the production sizing system of domestic and international brands, showed that the sizing interval of domestic brands were 6 months, whereas the international brands were 3 months f3r infants under 12 months. 3. Concerning fit, the areas causing most dissatisfaction were: the trunk length, sleeve length, inside leg length, and neck depth. The results showed that dissatisfaction with the suitability of the sizing of current infant coveralls according to the body part differed among the groups according to the month of age.

• Journal of muscle and joint health
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• v.19 no.2
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• pp.184-196
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• 2012

Purpose: This study aimed to investigate the degree of discomfort and to identify factors related with discomfort in patients wearing thigh-length compression stockings after orthopedic surgery. Methods: The participants were 105 patients wearing thigh-length compression stockings after orthopedic surgery at two hospitals in B city. Data were collected by the scale of discomfort in wearing compression stockings from July 5 to October 20, 2011. Results: Mean score of discomfort on wearing compression stockings was significantly higher at post-op. day 3 than day 1 (t=-2.30, p=.004). Discomfort scores for 'itching skin' and 'tightened leg' items were higher than others. There was significant difference in discomfort at post-op. day 1 according to surgical regions. The total score of discomfort at post-op. day 3 was positively related with the body mass index (r=.20, p=.041). Conclusion: Wearing thigh-length compression stockings to prevent deep vein thrombosis may cause physical and psychological discomfort for orthopedic surgical patients. To reduce discomfort in wearing compression stockings, nurses need to intervene discomfort and problems related to the stockings post-operatively.

• Advances in Computational Design
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• v.2 no.4
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• pp.257-271
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• 2017

There are many plain concrete arch bridges in Iran that have been used as railway bridges for more than seventy years. Owe to the fact that these bridges have not been designed seismically, and even may be loaded under high-speed trains, evaluation of fundamental frequencies of the bridges against earthquake and high-speed train vibrations is necessary for considering dynamics effects. To evaluate complex behavior of these bridges, results of field tests are useful. Since it is not possible to perform field tests for all arch bridges, these structures should be simulated correctly by computers for structural assessment. Several parameters are employed to describe the bridges, such as number of spans, length of spans, geometrical and material properties. In this study, results of field tests are used for modal analysis and adapted for 64 three dimensional finite element models with various physical parameters. Computer simulations show length of spans has important effect on fundamental frequencies of plain concrete arch bridge and modal deformations of bridges is in longitudinal and transverse directions. Also, these results demonstrate that fundamental frequencies of bridges decrease after increasing span length and number of spans. Plus, some relations based in the number of spans (n) and span length (l) are proposed for calculation of fundamental frequencies of plain concrete arch bridge.

• KCID journal
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• v.21 no.1
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• pp.118-126
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• 2014

In this study, the use of the spur of riverbank technique is being investigated. The spur of the riverbank typically reduces the velocity of flow and protects the embankments by increasing friction along the water and the banks. This also has an effect in the rise of water level upstream. It is also used for the rectification of riverside line and restoration of the waterway through sedimentation near the spur of the riverbank. In this study, physical-scaled experiments are conducted to investigate the process of creating a mild meandering channel using the spur of the riverbank with varying water flows and sedimentation functions. The hydraulics observations are taken with respect to the varying heights and length of the riverbank's spurs and the distance between each spur for the formation of the mild meandering channel. It is observed that for 1.06 times of the meander length, it requires 2 times of the interval with each spur of river width. Similarly, 1.25L times of the meander length, it requires 0.5 times of the interval with each spur of river width. The sand accumulation is induced by the spur of riverbank when the spur of riverbank's heights are more than 40% of water depth and the length of the spur of riverbank needs under than 20% of river width for avoid exaggerated sand accumulation in the center of channel.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.4 s.334
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• pp.21-28
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• 2005

SC-FDE (Single Carrier with Frequency-Domain Equalization), one of physical layers of IEEE802.16, is less sensitive to nonlinear power amplifiers than OFDM while its complexity and performance is comparable. The guard interval length in SC-FDE should be greater than the maximal delay spread. While a delay spread is small in most wireless communication environments, a very large delay spread can be possibly encountered in the mountain areas or due to the repeaters. This paper proposes SC-FDE with variable-length guard intervals. In the proposed method the guard interval length can be determined per each cell or per each subscriber stations.

• The Research Journal of the Costume Culture
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• v.18 no.3
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• pp.541-549
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• 2010

The purposes of this study were to examine the slacks purchases and wearing satisfaction among old-aged women who were highly dissatisfied with their bodies and fit due to physical changes and to provide some basic data needed to develop slacks patterns to meet their needs. A survey was taken among 223 old-aged women aged 60~79 living in Seoul. Using the SPSS 12.0 program, the collected data were analyzed in descriptive statistics, t-test, and crosstab. The result were as follows: the most used place for them to shop slacks was a market(including the Dongdaemun and Namdaemun market), which was followed by a department store and a discount store in the order. As for their preference for slacks according to age, those who were in their sixties most preferred straight-line slacks, while those who were in their seventies semistraight-type slacks. As for fit for each body part according to age, there were significant differences only in crotch length. Those who were in their seventies were more dissatisfied with crotch length than those who were in their sixties, feeling that crotch length was short. As for their experiences of repair after purchasing a pair of slacks, 82.5% said they had such an experience. Most of the repairs with length, waist and slacks width involved in size reduction.

• Child Health Nursing Research
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• v.8 no.2
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• pp.204-216
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• 2002

The purpose of this study was to investigate the effect of massage therapy on weight gain, length and head circumference in instituted infants. This study utilized nonequivalent control group with repeated measuring by quasi experimental design. Fifty eight instituted infants in Daejeon city were selected for the study. Fifty eight infants were randomly assigned two groups, one served as the control group and the other was experimental group to whom massage therapy was given. For the experimental group, massage protocol(developed by Field, 1986) was applied 2 times a day, mid-morning and early evening, for 4 weeks for each infants by researcher and trained research assistants. As a weight weighing instrument, electronic indicator scale (Cas Co., Korea) was used. The result of this study were summarized as follows; 1.A repeated measures ANOVA identified a significant group by time effect over the four weeks of intervention(F=14.69, p < .0001). Infants assigned to experimental group gained more weight than control group infants. 2. T-test identified that significant differences in length(t=2.60, P=.013) and head circumference(t=4.27, P=.000). Infants assigned to experimental group had more length and head circumference than control group infants. In conclusion, Massage therapy improved weight gain, length and head circumference of instituted infants. Therefore, it is recommended to utilize massage therapy as a nursing intervention for instituted infants.

• Geomechanics and Engineering
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• v.34 no.6
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• pp.623-636
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• 2023

This study utilized small-scale physical model tests to investigate the impact of different types of geosynthetics, including geocell, planar geotextile, and wraparound geotextile, on the behaviour of strip footings placed on 0.8 m thick soil fills and backfills with a slope angle of 70°. Bearing capacity and settlement of the footing and failure mechanisms are discussed and evaluated. The results revealed that the bearing capacity of footings situated on both unreinforced and reinforced slopes increased with a greater embedment depth of the footing. For settlement ratios below 4%, the geocell reinforcement exhibited significantly higher stiffness, carrying greater loads and experiencing less settlement compared to the planar and wraparound geotextile reinforcements. However, the performance of geocell reinforcement was influenced by the number and length of the geocell layers. Increasing the geocell back length ratio from 0.44 to 0.84 significantly improved the bearing capacity of the footing located at the crest of the reinforced slope. Adequate reinforcement length, particularly for geocell, enhanced the bearing pressure of the footing and increased the stiffness of the slope, resulting in reduced deflections. Increasing the length of reinforcement also led to improved performance of the footing located on wraparound geotextile reinforced slopes. In all reinforcement cases, reducing the vertical spacing between reinforcement layers from 100 mm to 75 mm allowed the slope to withstand much greater loads.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.2 s.110
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• pp.78-86
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• 2005

Hwaseonji(Korean traditional paper) used for writing and painting has been made from the mulberry bast-fiber and the short-length fiber pulps, wood pulps. However, besides wood pulps, other short-length fiber pulps also can be used instead of wood pulps. Hence, this research was carried out to make the various Hwaseonjis with the different properties, using the five kinds of short-length fiber pulps respectively. The short-length fiber pulps used in this research were softwood bleached kraft pulp(SwBKP) hardwood bleached kraft pulp(HwBKP), rice-straw bleached sulfite pulp(RsBSP), bamboo bleached kraft pulp(BbBKP) and recycled pulp from vellem paper(RP). And, the mixture ratios of the mulberry bast-fiber pulp and short-length fiber pulps were 100:0, 80:20, 60:40, 40:60 and 20:80. After various Hwaseonjis were made from different mixtures mentioned above with hand-made method, physical properties and chinese ink blot property of each paper were measured. The strengthes were the highest in the Hwaseonji made from the mixture of the mulberry bast-fiber pulp and SwBKP. However, chinese ink blot property and smoothness were better when RsBSP, BbBKP or RP were mixed into the mulberry bast-fiber pulp. As a result, the various kinds of Hwaseonjis which the users can choose based on their needs were made.