• 제목/요약/키워드: intensity control

검색결과 2,292건 처리시간 0.027초

Oligomerized polyphenols in lychee fruit extract supplements may improve high-intensity exercise performance in male athletes: a pilot study

  • Kawamura, Aki;Hashimoto, Shun;Suzuki, Miho;Ueno, Hiromasa;Sugita, Masaaki
    • 운동영양학회지
    • /
    • 제25권3호
    • /
    • pp.8-15
    • /
    • 2021
  • [Purpose] Excessive reactive oxygen species (ROS) induced by prolonged high-intensity exercise can cause structural and functional damage. Antioxidant polyphenol supplementation, which reduces ROS levels, may improve high-intensity exercise performance. We evaluated the effect of lychee fruit extract, which contains high levels of low-molecular-weight oligomerized polyphenols, on high-intensity exercise performance. [Methods] Ten male athletes were included in an open-label trial that consisted of control and intervention phases, with a 7-day washout period between phases. The participants were administered oligomerized lychee fruit extract for seven days, whereas no intervention was given in the control phase. High-intensity intermittent exercise and the Wingate test were performed. The power output, blood lactate levels, reactive oxygen metabolite levels, biological antioxidant potential, heart rate, and rate of perceived exertion were measured. [Results] The average power output was significantly higher in the intervention phase than in the control phase (P < 0.01), while the change in blood lactate levels was significantly lower in the intervention phase than in the control phase (P < 0.05). The average heart rate was significantly higher in the intervention phase than in the control phase (P < 0.05), without changing the rate of perceived exertion. Although there was no difference in reactive oxygen metabolite levels between the phase, the change in biological antioxidant potential was larger in the intervention phase than in the control phase (P = 0.06). The Wingate test showed no significant differences between the phase. [Conclusion] Short-term loading with oligomerized lychee fruit extract may increase performance during high-intensity intermittent exercise by improving metabolism.

빔셰이퍼 마스크를 이용한 레이저 빔의 강도 분포 제어 (Control of Intensity Distribution Profile of Laser Beam using Beam Shaping Mask with Random Array Slits)

  • 오재용;박덕수;신보성
    • 한국레이저가공학회지
    • /
    • 제15권2호
    • /
    • pp.11-14
    • /
    • 2012
  • In this paper, we have made a proposal concerning the beam shaping mask(BSM) using random-array slits to control intensity distribution profile of laser beam and demonstrated its proprieties experimentally. When a lot of slits are set out irregularly, diffraction patterns of light does not appear but granularity patterns as a bundle of fibers appear. Intensity distribution profile is controlled by densities distribution of circular slits arrayed randomly because the number of slits and its area means amount of light energy through BSM. Namely as the number of slits in high intensity area is increased and that in low intensity area decreased, amount of light energy is same over all local parts. So gaussian intensity distribution could be changed to flat-top.

  • PDF

Effects of High-intensity Intermittent Training and Moderate-intensity Training on Cardiopulmonary Capacity in Canoe and Kayak Paddlers during 8 Weeks

  • Kim, Ah-Ram;Shin, Won-Seob
    • 대한물리의학회지
    • /
    • 제9권3호
    • /
    • pp.307-314
    • /
    • 2014
  • PURPOSE: The purpose of this study was to investigate the effects of high intensity intermittent training on cardiopulmonary capacity in canoe and kayak paddlers. METHODS: A total of 16 canoe and kayak paddlers were participated in this study. Experimental group(n=8) was performed high-intensity intermittent training and control group(n=8) was moderate intensity training. All subjects performed a treadmill test in order to compare the difference before and after the intervention. Finishing the test, all subjects were measured to their heart rate(HR), forced vital capacity(FVC), forced expiratory volume in one second (FEV1) and forced expiratory ratio(FEV1/FVC). Recovery of heart rate(RHR) was calculated using the HR. HR and pulmonary flow values was measured before and during the intervention period per 2, 4, 6 and 8 weeks. To compare the differences over time between experimental group and the control group, used(time${\times}$group) two-way repeated measures ANOVA. One-way repeated ANOVA was performed to determine where differences over time within-group. RESULTS: One-way repeated ANOVA revealed a significant difference in the experimental and control group. In experimental group, %RHR3min and FEV1 were significantly increased after 4 weeks(p<.05). Also, %RHR1min, FVC and FEV1/FVC were significantly increased after 6 weeks(p<.05). In control group, %RHR1min, %RHR3min, FVC, FEV1 and FEV1/FVC were significantly increased after 6 weeks(p<.05). CONCLUSION: Not only moderate training but also high-intensity intermittent training contributes to cardiopulmonary capacity in canoe and kayak paddlers. Although high-intensity intermittent training is very short time, the training has high degree of efficiency. Therefore, developed this training in the future, it will be better to improve the cardiopulmonary capacity for athletes and healthy people.

External Magnetic Field of Journal Bearing with Twined Solenoid

  • Zhang, Yanjuan;Wang, Jianmei;Li, Decai
    • Journal of Magnetics
    • /
    • 제22권2호
    • /
    • pp.291-298
    • /
    • 2017
  • In this paper, the distribution of internal magnetic induction intensity of oil-film bearing twined solenoids was proposed. The magnetic field was generated by solenoids and magnetized bearing. The magnetized bearing was simplified as solenoid model. The mathematical model of magnetic induction intensity at any point of finite solenoid was deduced. Through experiment method, the distribution of the internal magnetic induction intensity of oil-film bearing and the magnetizing current formula of bearing was obtained. Further, the magnetic induction intensity distribution of magnetization bearing was solved successfully. The results showed that the magnetic induction was a second-degree parabola with open upwards along the axial plane and the distribution of magnetic induction intensity was opposite to the rule of magnetic induction intensity generated by solenoids. In addition, the magnetic flux density increased linearly with the increase of current.

The Three-year Effect of Thinning Intensity on Biomass in Larix kaempferi and Pinus koraiensis Plantation

  • Chhorn, Vireak;Seo, Yeongwan;Lee, Daesung;Choi, Jungkee
    • Journal of Forest and Environmental Science
    • /
    • 제36권1호
    • /
    • pp.17-24
    • /
    • 2020
  • This study aimed to figure out and compare the increment of biomass by thinning intensity focused on the plantation of the two major coniferous species (Larix kaempferi and Pinus koraiensis) of South Korea. The inventory interval was three years under the effects of three types of thinning treatments; control (no thinning), light (20% thinning) and heavy (40% thinning). The results showed standing biomass increment of both species decreased as thinning intensity increased (heavylight>control). Meanwhile, the lowest of on-site biomass changes occurred in the control plot, and the greatest was in the heavy thinning plot because thinning was involved with leaving the felling residual biomass (leaves, branches and roots) on the site. According to the results from this short-term study, unthinned stands is preferable for maximizing standing biomass as well as carbon sequestration. However long-term investigation should be considered in order to see more clear results.

High Cell Density Culture of Anabaena variabilis with Controlled Light Intensity and Nutrient Supply

  • Yoon, Jong-Hyun;Shin, Jong-Hwan;Ahn, Eun-Kyung;Park, Tai-Hyun
    • Journal of Microbiology and Biotechnology
    • /
    • 제18권5호
    • /
    • pp.918-925
    • /
    • 2008
  • Controlling the light energy and major nutrients is important for high cell density culture of cyanobacterial cells. The growth phase of Anabaena variabilis can be divided into an exponential growth phase and a deceleration phase. In this study, the cell growth in the deceleration phase showed a linear growth pattern. Both the period of the exponential growth phase and the average cell growth rate in the deceleration phase increased by controlling the light intensity. To control the light intensity, the specific irradiation rate was maintained above $10\;{\mu}mol/s/g$ dry cell by increasing the incident light intensity stepwise. The final cell density increased by controlling the nutrient supply. For the control of the nutrient supply, nitrate, phosphate, and sulfate were intermittently added based on the growth yield, along with the combined control of light intensity and nutrient concentration. Under these control conditions, both final cell concentration and cell productivity increased, to 8.2 g/l and 1.9 g/l/day, respectively.

저강도 복합운동프로그램이 여성노인의 일상생활체력과 낙상효능감에 미치는 영향 (Effect of a Low-Intensity Combined Exercise Program using Props on the Daily Living Fitness and Quality of Life of Elderly Women)

  • 이홍균;김은정
    • 대한물리의학회지
    • /
    • 제19권1호
    • /
    • pp.119-129
    • /
    • 2024
  • PURPOSE: The purpose of this study was to examine the effectiveness of a low-intensity combined exercise program on daily physical fitness parameters such as balance, flexibility, muscle strength, and fear of falling of elderly women in the community. METHODS: This study assigned 30 elderly women randomly into two groups: The control and experimental groups. The control group (n = 15) underwent routine gait. The experimental group (n = 15) underwent the low-intensity combined exercise. The exercise program in this study comprising combined exercise, including balance, flexibility, muscle strength training, and the exercise program using props was conducted twice a week for 8 weeks. RESULTS: The average age of the control and experimental groups was 77.27 years and 78.33 years, respectively. There were significant differences in static balance (t = -4.167, p < .001), dynamic balance (t = 2.463, p < .001), (t = -3.870, p < .001), (t = -2.262, p < .001), (t = -5.732, p < .001), (t = -6.573, p < .001), and fear of falling (t = -5.129, p < .001). CONCLUSION: The results show that low-intensity combined exercise is an effective intervention that improves physical health fear of falling in older women. The combined exercise program was found to be more effective in terms of physical function and fall-related psychological function compared to the control group that only walked.

BASIS RESEARCH ON NOISE CONTROL OF HEAD-FEEDING TYPE COMBINE HARVESTER USING SOUND INTENSITY METHOD

  • Sasao, A.;Iwasa, M.
    • 한국농업기계학회:학술대회논문집
    • /
    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
    • /
    • pp.752-760
    • /
    • 1993
  • We research ed on the noise control of a head feeding type combine harvester. It is a kind of combine harvester developed in Japan. And at present, it is used by most Japanese farmer. For a head-feeding type combine harvester it is very difficult to determine the sources of noise because it is a combination of reapers and automatic , threshers and several running parts. However we succeeded in finding out the sound sources of combine harvesters and analyzing their sound by the using sound intensity method. The sound intensity Method is a very up-to-date method to measure and analyze Sound Intensity Levels and sound directions at several measuring point sin a specified area. In this research, first a conventional sound level measurement method is used and secondly the sound intensity method. The first method shows a rather great limitation in allowed exposure duration. The second method shows pin-points the engine itself as being the main source of noise, causing sound flows a ross the operator's seat.

  • PDF

고정자극 전침과 변동자극 전침의 정상인 스트레스에 대한 심박변이도 변화 연구 (Effects of Fixed-intensity and Varied-intensity Electroacupuncture on Heart Rate Variability in Healthy People with Stress Task)

  • 임성근;이동화;권유정;이정찬;정창진;김용석;박경모;이상훈
    • Journal of Acupuncture Research
    • /
    • 제28권2호
    • /
    • pp.107-116
    • /
    • 2011
  • Objectives : This study was performed to investigate the effects of fixed-intensity and varied-intensity electroacupuncture on heart rate variability in healthy people with stress task. Methods : Forty healthy subjects were randomly assigned to either group A or group B or C. Group A received fixed-intensity electroacupuncture(F-EA) at $ST_{36}$ and $ST_{37}$. After 1 week wash out period to prevent overlapping residual effects, they received varied-intensity electroacupuncture(V-EA) in which the intensity was changed every two minutes based on individual heart rate variability at the same points. Group B received the treatments in reverse order. Group C received no intervention as a control group. Results : Control group showed a significant increase of LF and LF/HF during the 2nd working memory task, while both F-EA and V-EA did not. In addition, V-EA showed a significant increase of HF during 2nd rest while F-EA did not. Conclusions : These results suggest that F-EA and V-EA can inhibit sympathetic activation more than control group and that V-EA can enhance parasympathetic activation more than F-EA.

데이터 누적을 이용한 반사도 지역 지도 생성과 반사도 지도 기반 정밀 차량 위치 추정 (Intensity Local Map Generation Using Data Accumulation and Precise Vehicle Localization Based on Intensity Map)

  • 김규원;이병현;임준혁;지규인
    • 제어로봇시스템학회논문지
    • /
    • 제22권12호
    • /
    • pp.1046-1052
    • /
    • 2016
  • For the safe driving of autonomous vehicles, accurate position estimation is required. Generally, position error must be less than 1m because of lane keeping. However, GPS positioning error is more than 1m. Therefore, we must correct this error and a map matching algorithm is generally used. Especially, road marking intensity map have been used in many studies. In previous work, 3D LIDAR with many vertical layers was used to generate a local intensity map. Because it can be obtained sufficient longitudinal information for map matching. However, it is expensive and sufficient road marking information cannot be obtained in rush hour situations. In this paper, we propose a localization algorithm using an accumulated intensity local map. An accumulated intensity local map can be generated with sufficient longitudinal information using 3D LIDAR with a few vertical layers. Using this algorithm, we can also obtain sufficient intensity information in rush hour situations. Thus, it is possible to increase the reliability of the map matching and get accurate position estimation result. In the experimental result, the lateral RMS position error is about 0.12m and the longitudinal RMS error is about 0.19m.