• Title/Summary/Keyword: endurance time method

Search Result 81, Processing Time 0.023 seconds

Influence of Clothing Weight on the Motor Ability -Focusing on the Kindergartners- (착의량이 운동능력에 미치는 영향에 관한 연구 - 유치원 아동을 중심으로-)

  • Song Myung-kyun;Choi Jeong-wha
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.12 no.1 s.26
    • /
    • pp.13-26
    • /
    • 1988
  • As the culture develops, the body of children nowadays improves, but their physical fitness is weaker than that of children in the past. If physical fitness strengthens through clothing, this must be the easiest and the most efficient long-range training method. To find out the solutions on the above mentioned problems through clothing, this study was made for the analysis of the correlations of clothing weight and physical fitness. The children's endurance upon cold can be explained by the physical fitness, and has relation with the clothing insulation. Therefore, motor ability was measured as an index of physical fitness and clothing weight was measured as an index of insulation. This observation was made in Spring and Fall, 1985, in which 339 kindergartners and their mothers were the subject. The results of the study were as follows: Physical fitness of children decreased in proportion to the clothing weight, and especially this can be seen in boys rather than in girls, and in Fall rather than in Spring. In case of the children who spent more time outdoors rather than indoors, who played in larger space, and who didn't have meat frequently, it turned out that their clothing weight was surprisingly lessened and their physical fitness was highly food.

  • PDF

A Review on VDT Syndrome of Work-Related Musculoskeletal Disorders (작업성 근골격계질환의 VDT 증후군에 관한 고찰)

  • Yang, Young-Ae;Hur, Jin-Gang;Kim, Hyun-Hee;Lee, Gyu-Chang;Lee, Ju-Sang;Jung, Shin-Ho;Ahn, Chang-Sik;Shim, Jae-Hun
    • Journal of Korean Physical Therapy Science
    • /
    • v.11 no.4
    • /
    • pp.20-28
    • /
    • 2004
  • The studys purpose were the effects of work posture, treatment method and prevention for Video Display Terminal(VDT) workers in Work-Related Musculoskeletal Disorders(WMSD) The results were as follows: 1. The prevalence rate of VDT workers in WMSD was $20{\sim}40%$. The complaint was mostly shoulder, neck, and hack area pain 2. VDT worker used to forward flexed posture and then affect of increase of muscle fatigue and pain 3. When exercise therapy PT and ADL training, were used workers decrease in pain, muscle strength, balance training, endurance strength and relief of psychiatricIn conclusion, VDT worker need good health and posture to rest and exercise with time space and treatment. It is best to prevent WMSD. VDT workers need health management by itself and systemic rehabilitation program by speciality therapist.

  • PDF

Optimal switching method of SI-Thyristor using internal impedance evaluation (SI-Thyristor의 내부 임피던스 계산을 통한 최적 스위칭 제어)

  • Ju, Heung-Jin;Kim, Bong-Seok;Hwang, Hwui-Dong;Park, Jeong-Ho;Ko, Kwang-Cheol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2010.06a
    • /
    • pp.122-122
    • /
    • 2010
  • A Static Induction Thyristor (SI-Thyristor) has a great potential as power semiconductor switch for pulsed power or high voltage applications with fast turn-on switching time and high switching stress endurance (di/dt, dV/dt). However, due to direct commutation between gate driver and SI-Thyristor, it is difficult to design optimal gate driver at the aspect of impedance matching for fast gate current driving into internal SI-Thyristor. Thus, to penetrate fast positive gate current into steady off state of the SI-Thyristor, it is proposed and proceeded the internal impedance calculation of the SI-Thyristor at steady off state with the gate driver while switching conditions that are indicated applied gate voltage, $V_{GK}$ and applied high voltage across anode and cathode, $V_{AK}$.

  • PDF

A Study on the Actual Condition Analysis and Improvement of Rebar Work in Korean Building Construction (국내 철근공사 실태분석 및 개선방안에 관한 연구)

  • Park, U-Yeol;Kim, Gwang-Hui;Gang, Gyeong-In
    • Journal of the Korea Institute of Building Construction
    • /
    • v.4 no.3
    • /
    • pp.83-91
    • /
    • 2004
  • With labor shortage and high-wage era, the construction cost is rising and the construction business is dull, demanding the construction environment of Korea to raise profitability through major cost savings and rationalization of construction management. However, although reinforcing bar(rebar) work, which greatly effects the building's safety, endurance, and construction time, is an important phase in construction, it holds serious problem of quality and productivity deterioration due to its characteristic of intensive-labor and maintaining of old work methods resulting in poor management, and costs increase. Therefor in this study to investigate current situation and problems of rebar work and to find methods of betterment, a survey was conducted to site engineers and individuals in division of cost estimate of domestic construction company. The survey questions were on the subjects of (1) calculating rebar quantity, (2) ordering and procurement, (3) rebar cutting and bending, and (4) rebar work management. Method of improvement was sought by analyzing the results of the survey

Characteristics of wastewater from unit systems of automative process for manufacture of paper mulberry pulp fibers (닥 펄프 제조공정 자동화에 따른 단위공정 폐수의 특성)

  • Hwang, Ji-Hyun;Hwang, Sung-Jun;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.47 no.3
    • /
    • pp.55-62
    • /
    • 2015
  • Paper mulberry fibers have been used as fibrous raw materials for manufacturing traditional handmade paper, hanji for a long time. Compared to wood pulp fibers, pulp fibers from mulberry bast tissue have some benefits in physical and chemical properties due to their high D.P (degree of polymerization), M.W (molecule weight) and long fiber length. Specially, Korean handmade hanji shows outstanding characteristics in mechanical tensile strength, folding endurance, flexibility and long sustainable conservation properties. Therefore, hanji is widely applied to daily supplies, hygienic goods, medical supplies, clothing industries and so on. Recently, the potential demand of mulberry pulp fibers is more and more increased on the strength of high application fields. This study was focused on the possibility of wastewater recycling in unit operation systems for the development of automated mass production line. The properties and environmental loads of wastewater from debarking, cooking, bleaching and screening process were analyzed by means of COD, conductivity, turbidity and solid materials. The wastewater from debarking and cooking process was comparatively high in pollution load, and would be treated by additional approaches of chemico-physical method.

A Study on Strengthening of PSC Beam by Fatigue Experiment (피로 실험에 의한 PSC 부재의 성능개선기법에 관한 연구)

  • Kim, Hyun-Ho;Song, Jae-Pil;Kim, Ki-Bong;Chung, Young-Soo
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.7 no.1
    • /
    • pp.165-172
    • /
    • 2003
  • The fatigue problem of Prestressed Concrete(PSC) bridges are more serious than the other type of concrete bridges, because the cross sectional area and self weight of PSC bridges are smaller. The endurance of strengthening methods for PSC bridges are tested in this study. Glass fiber sheeting and external post-tensioning methods were applied. 1/5 scale PSC beams were made for fatigue test, same as static test. The range of repeated load is from 10% to 80% of yielding load with sine curve. The experimental results show that the failure cycle of strengthened members are increased compare to non-strengthened members. The members strengthened with glass fiber show better enhancement in fatigue problem than the members strengthened with external post-tensioning method, though the adhesion of glass fiber and concrete is failed, as increase of crack. With these experimental results, it can be said that the strengthening methods used in this study are efficient at extending the life time of aged PSC bridges.

The Analysis for Flow Circulation System in HANARO Flow Simulation Facility (하나로 유동 모의 설비의 유체순환계통 해석)

  • Park, Yong-Chul
    • The KSFM Journal of Fluid Machinery
    • /
    • v.7 no.1 s.22
    • /
    • pp.30-35
    • /
    • 2004
  • The HANARO, a multi-purpose research reactor of 30 MWth open-tank-in-pool type, has been under normal operation since its initial criticality in February, 1995. Many experiments should be safely performed to activate the utilization of the HANARO. HANARO flow simulation facility is being developed for the endurance test of reactivity control units for extended life time and the verification of structural integrity of those experimental equipments prior to loading in the HANARO. This facility is composed of three major parts; a half-core structure assembly, a flow circulation system and a support system. The flow circulation system is composed of a circulation pump, a core flow piping, a core bypass flow piping and instruments. The system is to be filled with de-mineralized water and the flow should be met the design requirements to simulate a similar flow characteristics in the core channel of the half-core structure assembly to the HANARO. This paper, therefore, presents an analytical analysis to study the flow behavior of the system. Computational flow analysis has been performed for the verification of system pressure variation through the three-dimensional analysis program with the standard $k-{\epsilon}$ turbulence model and for the verification of the structural piping integrity through the finite element method. According to the analysis results, it could be said that the design requirements and the structural piping integrity of the flow circulation system are satisfied.

The Effects of a 12-Week Walking Exercise Program on the Body Composition and Physical Fitness in Obese College Women (걷기운동이 비만 여대생의 신체조성과 체력에 미치는 효과)

  • Choi, In-Hee;Lee, Mi-Wha
    • Journal of Korean Public Health Nursing
    • /
    • v.22 no.1
    • /
    • pp.74-83
    • /
    • 2008
  • Purpose: To identify the effect of walking exercise on the body composition and physical fitness in obese college women. Method: The research design was a nonequivalent control group pretest posttest. Thirty-seven subjects were surveyed using a structured questionnaire, and measured for body composition and physical fitness. Twenty persons in the experimental group among the total sample participated in a 12-week walking program. The data were analyzed by $x^2$-test, and t-test with SPSS 10.1 program. Results: 1) BMI, body fat mass and percentage of body fat in body composition were significantly decreased in the experimental group compared to the control. However, there was no significant difference in skeletal muscle mass between the two groups. 2) Power among physical fitness was significantly increased in the experimental group. However, there was no significant difference in muscular strength (back strength), flexibility (sit and reach), muscular endurance (abdomen curl), power (standing high jump) or agility (trunk reaction time) between the two groups. Conclusion: The above results, confirmed the effectiveness of walking exercise as an effective nursing intervention in order to improve body composition.

  • PDF

Experiences of hospitalization among pregnant women with preterm labor in Korea: a phenomenological study

  • Lee, Joon-Young;Song, Yeoungsuk
    • Women's Health Nursing
    • /
    • v.27 no.3
    • /
    • pp.209-219
    • /
    • 2021
  • Purpose: The purpose of this study was to describe pregnant women's lived experiences of hospitalization due to preterm labor in Korea. Methods: This qualitative study adopted a phenomenological approach. Individual in-depth interviews were conducted with nine participants, over the age of 20 years, who had been hospitalized for more than 1 week after being diagnosed with preterm labor. All interviews were audio-taped and verbatim transcripts were made for analysis. The data were analyzed following Colaizzi's phenomenological method. Results: The participants' ages ranged from 26 to 36 years, and all were married women. They were hospitalized for 13.1 days on average. Five thematic clusters emerged from the analysis. 'Withstanding hospitalization for the fetus's well-being' describes women's feelings during preterm labor and their endurance during their prolonged hospitalization, rooted in their conviction that the fetus comes first. 'Endless frustration in the hospital' encompasses women's emotions while lying in bed and quietly thinking to themselves. 'Unmet physiological needs' describes participants' awareness of their inability to independently handle human physiological needs given the need for careful and limited movement. 'Gratitude for the support around oneself' reflects the support from family and medical staff. 'Shifting perceptions and accepting one's circumstances' describes accepting hospitalization and making efforts to spend their remaining time in the hospital in a meaningful way. Conclusion: The findings in this study provide a deeper understanding and insights into the experiences of Korean women with preterm labor during hospitalization, underscoring the need to develop interventions for these patients.

Load and Safety Analysis for Plow Operation in Dry Fields (건답에서 쟁기작업의 부하특성 및 안전도 분석)

  • Lee, Ju-Yeon;Nam, Ju-Seok
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.18 no.6
    • /
    • pp.9-18
    • /
    • 2019
  • This study derives load characteristics and analyzes the safety of plowshares operating in dry fields. We mounted a three-blade, reversible plow on a 23.7 kW tractor and measured the plow's tractive force as well as the torque from the engine output shaft on the rear axle under various working speeds (L4, M1, M2, M3). We chose a Korean test site of Seomyeon, Chuncheon with sandy soil texture, as determined using the USDA method. We constructed the load spectrum for torque and tractive force using measured data and derived the fatigue life of the plowshare from a stress-cycle (S-N) curve of the plow material. Our results show that the M3 gear maximizes the driving shaft torque loads and, applying the tractive force load spectrum, creates a cumulative damage sum of $4.14{\times}10^{-5}$. Considering sampling time, we estimate a fatigue life of 805 hours while using the M3 gear. When using the other working speeds, however, all of the stress levels fell within the endurance limits and, therefore, our model predicts infinite plowshare lifetimes. For this analysis, we used a yield strength of 1,079 MPa for the plowshare and static safety factors, analyzed using the maximum stress, between 6.83 and 8.63 under each working speed.