• Journal of the Korean Society of Clothing and Textiles
• /
• v.23 no.7
• /
• pp.965-970
• /
• 1999

This study was conducted to investigate the thermoregulatory characteristics of feet and legs by comparing with the physiological responses according to the covering parts of lower limbs. Five healthy female subjects wore three types of clothing-covered legs and feet(LF-C) with long trousers and socks exposed the legs(L-E) with half trousers and socks and exposed the legs and feet(LF-E) with only half trousers-when the subjects rested at $25^{\circ}C$ and were exposed to 18$^{\circ}C$ for 90 min. Rectal temperatures (Tre) were maintained higher in LF-E than L-E and LF-C at both environments. Decreases of The after exposure to 18$^{\circ}C$ were significantly smaller in LF-E than L-E and LF-C and almost same in L-E and LF-C Heat production in both environments increases of heat production and weight loss after exposure to 18$^{\circ}C$ were not significant among three types of clothing. From these findings it would be suggested that the legs would play the little role of voluntary thermoregulation as vasoconstriction and the role of the legs depend on thermal conditions of feet while the feet play the positive role of voluntary thermoregulation in terms of heat conservation in cool environment.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.16 no.4
• /
• pp.27-36
• /
• 2014

Lower body type of middle-aged(40 to 59) women was analyzed to develop body type-specific slacks. The analysis has four factors. Factor one is hip and leg type. Factor two is lower body height and length. Factor three is waist type, and factor four is hip length. By conducting a cluster analysis with scores of four factors, it came to have three types of classifications. Type one is a rectangular-shaped slim type. Women of this type have a high and lengthy lower body and middle-length hip. They have thin and small legs, their lower body is the longest, and the smallest with small curve among three types. Type two is the diamond-shaped obese type. They have a high and long lower body and legs are medium they are the most obese type. Type three is the large, trapezoidal-shaped, slightly overweight type. They have the longest and the biggest leg and hip. But the length and height of the lower body is the shortest among the three, and the hip is small. Legs are the thickest and shortest. The hip is big compared with the waist and is the longest. They have big hips and thick legs.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.883-889
• /
• 2005

Micro robots have been developed for many applications: medical, industrial, military, and so on. A small mobile robot was built and it has three legs made of bimorph piezoelectric actuators. It proceeds by vibrating the rear leg and it rotates by vibrating one of the front legs. The locomotion of the robot is described by relative position of mass center and the friction between the legs and the floor. This paper describes the principles of locomotion and modeling of the robot Modeling was simulated to investigate the dynamics of its mobility. The simulation results verified the modeling by showing similar movement of the robot as measured. It remained, however, several problems through experiments such as crooked direction of forward movement and proceeding speed.

• Journal of Species Research
• /
• v.10 no.3
• /
• pp.287-300
• /
• 2021

Three new species of Myzomolgus are described as associates of sipunculans from a tidal flat in Phuket, Thailand. As diagnostic features, Myzomolgus leptocercosus n. sp. has elongate caudal rami which are 10.7 times longer than wide, 5 setae and a conical process on the first antennular segment, an armature formula 1, 0, 1+sucker, and 6 of antenna, and an inner coxal seta on all swimming legs. Myzomolgus spatulatus n. sp. lacks a rostrum, but bears 4 setae and a spatulate process on the first antennular segment, an armature formula 0, 0, 2+sucker, and 6 of the antenna, the inner coxal seta on legs 1-3, and 5 armture elements on the third endopodal segment of legs 1-3. Myzomolgus cucullatus n. sp. has short caudal rami which are 1.60 times longer than wide, a broad, hood-like tergite of fouth pedigerous somite, 4 setae only on the first antennular segment, the armature formula 0. 0. 2+sucker, and 6 of the antenna, and no iiner coxal seta on the swimming legs.

• Journal of the Korean Society of Physical Medicine
• /
• v.12 no.3
• /
• pp.73-77
• /
• 2017

PURPOSE: The present study aimed to measure muscle activities in the pectoralis major, the erector spinae, and the quadriceps femoris according to support surface states of arms and legs during plank exercise. METHODS: The subjects of this study were 21 healthy males in their 20s and their muscle activities at three states were measured as follows: The first state was where the support surface of arms and legs was stable. The second state was where only arms were unstable, and the third state was where only legs were unstable. Electromyography (EMG) was used to measure muscle activities. Pectoralis major, quadriceps femoris, and elector spinae were measured for muscle activities. RESULTS: The muscle activities in the pectoralis major were statistically high when arms were unstable. The muscle activities in the quadriceps femoris were statistically high when legs were unstable. The muscle activities in the erector spinae were higher when arms and legs were unstable compared to that at the stable support surface. No significant difference was revealed statistically when arms and legs were unstable. CONCLUSION: If the instability of arms and legs is employed during plank exercise, exercise on the upper and lower bodies or the erector spinae is expected to be more effective.

• Journal of Korean Clinical Nursing Research
• /
• v.26 no.3
• /
• pp.385-394
• /
• 2020

Purpose: This experimental study with nonequivalent control group and pre/post-tests aims to investigate the effects of a complex leg exercise program on severity of restless legs syndrome, sleep quality, depression, and physical performance in patients with maintenance hemodialysis. Methods: Patients in the experimental group were provided with the leg exercise program three times a week for eight weeks, a total of 24times, through watching videos during hemodialysis from August 1, 2017 to October 25. The experimental group and control group consisted of 22 people each. Data were analyzed using descriptive statistics, χ2 test, Fisher's exact test, and independent t-test utilizing SPSS/WIN 22.0. Results: After providing with the leg exercise program, these were level of restless legs syndrome and depression were significantly decreased in the experimental group (t=2.79, p=.032; t=0.53, p=.036, respectively). However, sleep quality and physical performance did not have significant difference between the two groups (t=0.02, p=.947; t=1.74, p=.957, respectively). Conclusion: A complex leg exercise program appears to be beneficial in improving restless legs syndrome and depression in maintenance hemodialysis patients with restless legs syndrome.

• Journal of Power Electronics
• /
• v.13 no.2
• /
• pp.223-231
• /
• 2013

A modular three-phase multilevel inverter especially suitable for electrical drive applications has been previously presented. This topology is based on series connection of power cells in which each cell comprised of two inverter legs in series. In this paper, in order to generate the maximum number of voltage levels with reduced number of switches, three algorithms are proposed for determination of the magnitudes of dc voltage sources. In addition, a new hybrid multilevel inverter is proposed that is composed of series connection of the previously presented multilevel inverter and some H-bridges. The proposed topology has been compared with some other presented multilevel inverters. The performance of the proposed multilevel inverter has been verified by simulation and experimental results of a single-phase 39-level multilevel inverter.

• Journal of Power Electronics
• /
• v.19 no.6
• /
• pp.1337-1350
• /
• 2019

This paper proposes a Phase-Shift Triple Full-Bridge (PSTB) Zero-Voltage Zero-Current-Switching (ZVZCS) converter with a high switching frequency and high efficiency. In the proposed converter, all three bridge legs are shared leading-legs, and all three transformers work in the Discontinuous Conduction Mode (DCM). Thus, all of the switches and diodes in the PSTB ZVZCS can be soft switched. Moreover, since all of the transformers can pass energy from the primary-side to the secondary-side when their primary-side currents are not zero, there is no circulating current. As a result, the PSTB ZVZCS converter can achieve a high efficiency at high operating frequencies. A theoretical analysis and the characteristics of the proposed converter are presented and verified on a 1MHz 200~300V/24V 1.2kW hardware prototype. The proposed converter can reach a peak efficiency of 96.6%.

• Journal of the Korean Society of Mechanical Technology
• /
• v.20 no.6
• /
• pp.912-916
• /
• 2018

Crawling robots are advantageous in overcoming obstacles. These robots have characteristics such as light weight and outstanding mobility. In case of large robots, they have difficulties passing narrow gaps or entering the cave. In this paper, we propose a milli-scale hexapedal robot using 4-bar linkages. Two conditions are necessary to enable efficient walking. In short, the trajectory of the foot must be elliptical, and the lowest point of the foot should be the same. These conditions are satisfied with a novel leg design. The robot has a pair of three legs and the legs are coupled to operate simultaneously. Each set of the legs are installed to robot's both sides and the legs satisfy the equal lowest foot point and elliptical trajectory. As a result, this hexapedal robot can crawl with 0.56m/s speed.

• Korean Journal of Applied Biomechanics
• /
• v.21 no.2
• /
• pp.173-179
• /
• 2011

This study aims to analyse difference in biomechanical factors between dominant legs and recessive ones according to muscular imbalance during drop landing targeting talented children in sports. The subjects of the study were ten primary students who are attending to Sports Program for Talented Children organized by C university (age: $12.28{\pm}0.70$ year, height: $1.52{\pm}0.11$ m, and weight: $45.2{\pm}4.9$ kg). Strength legs were classified into dominant side and strengthless legs were classified into non-dominant legs. For three-dimensional analyses of the data collected, 6 video cameras(MotionMaster200, Visol, Korea) were used. To analyse ground reaction force, two force platforms(AMTI ORG-6, MA) were used and to analyse electromyograghy a 8-channeled wireless Noraxon Myoresearch made in USA was used at 1000 Hz for sampling. As a result, it was discovered that the dominants legs controlled knee bending motions more stably than strengthless legs as the maximum vertical ground reaction force was significantly high in dominant legs(p<.05), and joint moment of knee joints of the dominant legs was high(p<.05). Therefore, this study suggested that injury prevention program focusing on muscular balance as well as the existing sports programs for talented children should be developed based on results of the study and it is expected that the results will be useful for improvement of sports programs for talented children.