• Title/Summary/Keyword: runners

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Impact of Runner Development of Mother Plants during Seedling Strawberries on Daughter Plants Growth and Development during Phase of First Cluster (딸기 육묘과정 중 모주의 런너발생수가 자묘 소질과 1화방 수확기 생장에 미치는 영향)

  • Park, Gab-Soon;Ann, Seoung-Won
    • Journal of Environmental Science International
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    • v.25 no.1
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    • pp.147-153
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    • 2016
  • To investigate the impact of the number of runners developed from daughter plants during seedling on sapling growth and development during phase of first cluster, we examined four treatment groups that had 3-4, 5-6, 7-8, and 9-10 runners. As of June $5^{th}$, the group with 9-10 runners showed the highest number of saplings with more than 2 leaves, followed by groups with 7-8, 5-6, and 3-4 runners. Although observation on June $25^{th}$ and July $15^{th}$ showed a similar tendency for sapling numbers, no significant difference was detected between groups with 7-8 and 9-10 runners. The length of runners in the treated groups was similar to that in groups with 3-4 and 5-6 runners, with lengths of 49.4 mm and 48.0 mm, respectively, but runner length was significantly shorter in the group with 7-8 runners. Both the thickness and the weight of runners were highest in the group with 3-4 runners. The growth and development of daughter plants and root weight were similar between the groups with 3-4 and 5-6 runners, whereas both values were lower in groups with 7-8 and 9-10 runners. While stem crown thickness values were 8-7 mm and 8.5 mm in groups with 3-4 and 5-6 runners, respectively, groups with 7-8 and 9-10 runners had thinner stems of 7.1 mm and 6.2 mm, respectively. The fresh weight of saplings decreased as the number of runners increased. From the phase first cluster, leaf area and fresh weight were remarkably low in groups with 7-8 and 9-10 runners. Taken together, these results can be used to increase the production of high-quality saplings by providing a foundation for studies to investigate the impact of the number of runners developed from daughter plants on growth and development during the seedling period and the phase first cluster.

Comparison of Physical Characteristics and Lower Extremity Biomechanics of Elderly and Young Adult Runners (노인 러너의 신체특성과 하지관절의 생체역학적 비교)

  • Kim, Jong-Bin;Ha, Sunghe;Park, Sangheon;Yoon, Sukhoon;Ryu, Ji-seon;Park, Sang-Kyoon
    • Korean Journal of Applied Biomechanics
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    • v.29 no.3
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    • pp.145-155
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    • 2019
  • Objective: The purpose of this study was to compare the physical characteristics (bone mineral density, joint muscle strength) and running biomechanics between older adults and young adult runners to understand the changes of running strategy by aging. Method: Bone mineral density (Dual Energy X-ray Absorptiometry, USA) of lower lower extremity and muscle strength (Cybex Humac Norm [DEXA], CSMI, USA) were measured to identify the physical characteristics of 10 elderly (age: $67.70{\pm}3.30yrs$, height: $1.68{\pm}0.04m$, mass: $67.70{\pm}3.80kg$) and 10 young adults (age: $21.20{\pm}0.42yrs$, height: $1.73{\pm}0.06m$, mass: $72.11{\pm}4.15kg$). Running data was collected by using an instrumented treadmill (Bertec, USA) and 7 infrared cameras (Oqus 300, Qualisys, Sweden). Two-way repeated ANOVA analysis was used to analyze results at a significant level of .05 with Bonferroni post hoc analysis. Results: Compared to the young adult group, the elderly group showed statistically significant difference in physical characteristics and in running characteristics. Elderly runners showed lower BMD and muscle strength compared with young runners (p<.05). In the running parameters, elderly runners tend to show shorter contact time and stride length compared with young runners (p<.05). In the joint angles, elderly runners showed smaller range of ankle motion compared with young runners (p<.05). Finally, elderly runners showed lower level of joint moment, joint power, and GRF compared with young runners in each running speed (p<.05). Conclusion: The running behavior of the elderly performed periodic running was similar to many variables of young adults. However, there were noticeable differences found in the ankle joints and most kinetic variables compared with young adult runners. This discrepancy may propose that elderly runners should consider appropriate running distance and intensity in the program.

The change of the Pre-Post a maximal exercise on the Physiological Variable in the athletics children runners (소년체전 육상선수들의 최대 운동부하 전.후 혈중 생리적 변인 변화에 관한 연구)

  • Koo, Sung-Wan;Park, Han-Su
    • Journal of Korean Physical Therapy Science
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    • v.11 no.1
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    • pp.5-13
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    • 2004
  • The purpose of this study was to the Pre-Post maximal exercise for analyze the Physiological Variable(Lactate, LDH, Glucose) in the runners. The subjects were 12 volunteers 6 sprinters and 6 distance runners who agreed to intention of this study. Subjects performed until possible all-out trials. Blood samples were taken from a median cubital vein Pre-Post exercise and every rest 5min during the all-out trial. The results obtained were summarized as follow ; 1) Lactate of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, but showed significant in sprinters and distance respectively 2) LDH of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and that showed no significant in sprinters and distance respectively 3) Glucose of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and showed no significant in distance, but showed significant in sprinters therefor, since the runners has an intermittent characteristic which includes a frequent momentary change, it needs the fitness training that being consisted of various training, in the training method, it needs the training process which is from the whole fitness to specific fitness to improve general physical ability.

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Enhanced functional and structural properties of high-density lipoproteins from runners and wrestlers compared to throwers and lifters

  • Lee, Hwa-Hyung;Park, Jeong-Euy;Choi, In-Ho;Cho, Kyung-Hyun
    • BMB Reports
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    • v.42 no.9
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    • pp.605-610
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    • 2009
  • Plasma high-density lipoprotein cholesterol (HDL-C) levels are inversely correlated with the risk of cardiovascular disease, and are known to increase with repetitive exercise. In the current study, HDL fractions from athletes' sera were isolated and compared as a function of the type of sport (runners [n = 10], throwers [n = 10], wrestlers [n = 10], and weight lifters [n = 8]), and as an age- and gender-matched reference group (n = 14). Among athletes, HDL from runners had the strongest antioxidant activity. Immunodetection showed that runners and wrestlers had the highest levels of apoA-I and lowest levels of apoA-II in their HDL. Electron microscopy also revealed that HDL2 of runners and wrestlers were the largest in size. In conclusion, although all athlete groups had significantly better serum lipid/lipoprotein profiles than the reference group, runners and wrestlers had the most desirable lipoprotein function and structure, including antioxidant activity, HDL-associated enzyme activities and increased particle size.

Vibration Behavior and Dynamic Stress of Runners of Very High Head Reversible Pump-turbines

  • Tanaka, Hiroshi
    • International Journal of Fluid Machinery and Systems
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    • v.4 no.2
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    • pp.289-306
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    • 2011
  • In the development of very high head pumped storage projects, one of the critical problems is the strength of pumpturbine runners. Data obtained by stress measurements of high head pump-turbine runners indicated that dynamic stress due to the vibration of runner might be detrimental, possibly to cause fatigue failure, if the runner were designed without proper consideration on its dynamic behaviour. Numerous field stress measurements of runners and model tests conducted with hydrodynamic similarity revealed that the hydraulic excitation force developed by the interference of rotating runner blades with guide vane wakes sometimes would induce such heavy vibration of runner. Theoretical and experimental investigations on both the hydraulic excitation force and the natural frequencies of runner have been conducted to explore this forced vibration problem.

Comparative Analysis of the Pre-Post a Treadmill Exercise on the Blood Lactate, LDH and Glucose in the Runners (육상선수들의 트래드밀운동 전 ${\cdot}$ 후 Blood Lactate, LDH, Glucose의 비교 분석)

  • Park, Han-Su;Shin, Byung-Cheul;Chae, Jeong-Ryong;Jo, Sung-Cho;Jeon, Hee-Young;Kim, Hyunng-Jun;Kim, Mo-Kyung
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.5
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    • pp.1254-1260
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    • 2006
  • The purpose of this study was to the Pre-Post submaximal exercise for analyze the Blood Lactate, LDH(Lactate Dehydrogenase) and Glucose in the runners. The subjects were 12 volunteers 6 sprinters and 6 distance runners who agreed to intention of this study. Subjects peformed until possible all-out trials. Blood samples were taken from a Ante cubital vein Pre-Post exercise and every rest 5min during the all-out trial. The results obtained were summarized as follow; 1) Blood Lactate of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, but showed significant in sprinters and distance respectively. 2) Serum LDH of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and that showed no significant in sprinters and distance respectively. 3) Blood Glucose of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and showed no significant in distance, but showed significant in sprinters. These data indicate first that the value of 4mmol/${\ell}$, commonly referred to as OBLA(Onset of Blood Lactate),may often underestimate the upper limit of tolerance to lactate during a maximal endurance peformance test until all-out. second, our date suggested that the sprinters exercise decreases serum LDH activities and the distance increases serum LDH activities. therefore serum LDH concentration changed following a different exercise. Third. for the concentration of the glucose in blood the sprinters was show to be higher. However it needs more studies to find out the relationship between this result and the fitness factor. therefor, since the runners has an intermittent characteristic which includes a frequent momentary change, it needs the fitness training that being consisted of various training. in the training method, it needs the training process which is from the whole fitness to specific fitness to improve general physical ability.

Development of Injection Mold for Subminiature Lenses Using Shell Runners Containing Multiple Holes (다공성 박판형 러너를 사용한 초소형 렌즈 사출금형 개발)

  • Yoon, Seung Tak;Park, Keun
    • Journal of the Korean Society for Precision Engineering
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    • v.32 no.11
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    • pp.961-968
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    • 2015
  • This study aims to develop an efficient mold structure for the injection molding of a subminiature lens, using shell-type runners instead of traditional cylindrical runners. While the shell runner has the advantage of shorter cooling time due to its thinner geometry, this smaller thickness causes an increase in injection pressure. In this study, the design of the shell runner was modified to contain multiple holes for the purpose of reducing injection pressure. Numerical analyses were performed for shell runners of various hole-shapes, and the resulting filling and cooling characteristics were discussed; the rhombic hole showed the best result for both filling and cooling characteristics. Subsequently, injection molding experiments were performed using an injection mold fabricated based on the rhombic design. The lens parts were successfully molded with highly-reduced cycle time and without degradation of part quality.

Structural Load Bearing Capacity of Wall System Framed by Studs and Runners using Square Steel Tubes (각형강관을 이용한 스터드-런너 골조형 벽체시스템의 구조내력 성능평가)

  • Kim, Ho Soo;Hong, Seok Il;Lim, Young Do
    • Journal of Korean Society of Steel Construction
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    • v.17 no.3 s.76
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    • pp.253-262
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    • 2005
  • Because the framed wall system using steel studs and runners with square steel tubes as structural elements is reinforced by the horizontal members called runners, it has more strength and load bearing capacity than the steel house wall system. Also, this system improves adiabatic and sound insulation performance by filling up the autoclaved lightweight concrete. We need to evaluate load bearing capacity according to the axial load and lateral load in case this system is applied in the housing system with 3~5 stories through variations in intervals for the runners under the placement effect of autoclaved lightweight concrete. Therefore, this study seeks to analyze axial and shear behavior of the framed wall system according to the placement effect of autoclaved lightweight concrete, and to secure safety for the vertical and lateral loads.

Development of Herbal Drink to Improve Aerobic Capacity in Elite Endurance Runners (건각탕(健脚湯) 섭취가 엘리트 장거리 달리기 선수의 유산소성 능력 향상에 미치는 영향)

  • Lee, Jeong-Pil;Jung, Hee-Jung;Ahn, Kyoo-Seok;Oh, Jae-Keun;Choe, Yeong-Jin
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.3
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    • pp.563-571
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    • 2006
  • The purpose of this study was to identify the effects of oriental herbal drink to improve aerobic capacity in elite endurance runners. 14 male elite college runners were participated and divided into two group; i ) oriental herbal drink group (OG), ii ) placebo group (PG). All subjects were completed treadmill exercise protocol using GXT at before (B) and after (A) experimental treatment of one week. The V02max, anaerobic threshold (AT) were measured by gas analysis and heart rate (HR) were measure by polar system at pre, max, post, post 30 min and post 60 min. Blood samples were collected to analyze blood components. The V02max were significantly increased in OGA compared to OGB whereas the V02max and AT in OGA were significantly higher than PGA. The blood lactate concentration were shown higher decrease rate in OGA compared to Doth OGB and PGA during recovery whereas LDH and Na were significantly increased in OGA compared to both OGB and PGA. The blood concentrations of CI and K were significantly increased in OGA compared to PGA. There were no significant differences were founded in WBC, RBC, Hct, Hb and other components associated with energy sources(glucose, TG, TC, HDL, LDL, creatinine, CPK). These results suggested that this oriental herbal drink can be administrated to improve aerobic capacity in long distance runners.

A two-phase servo motor control circuit for the nut-runners employing the tightening torque control method (자동나사체걸기의 토크제어를 위한 AC 2상서보모터 제어회로 설계)

  • 김기엽;김일환;박찬웅
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10b
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    • pp.312-316
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    • 1987
  • A simple hybrid circuit to control the two-phase AC motor of the nut-runners which employ the tightening torque control system is described in this paper. The circuit has emphasis on the low-cost implementation. The circuit constitutes of the V/F converter using a timer IC, the pulse width modulator using the fastening torque signal and the two-phase logic sequencer.

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