• Title/Summary/Keyword: Endurance

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Effects of Ginseng Saponins in Energy Metabolism, Memory, and Anti-neurotoxicity

  • Wang Lawrence C.H.;Lee Tze-fun
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.55-65
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    • 2002
  • Ginseng has been used as a key constituent in traditional medicine prescriptions for centuries. Other than its well-known anti-stress and adaptogenic properties, ginseng has also been shown to be very effective in treating age-related deterioration in metabolic and memory functions. Although it is generally believed that the saponin (GS) fraction of the ginseng root accounts for the bioactivity of ginseng, a direct demonstration on which ginsenoside does what is still generally lacking. In the past decade, our laboratory has endeavored to identify the active GS components involved in energy metabolism, memory, and anti-neurotoxicity. To examine the ergogenic effects of GS in enhancing aerobic capacity, rats were subjected to either severe cold ($40^{\circ}C$ under helium-oxygen, two hours) or exercise workload $(70\%\;VO_{2}max,$ to exhaustion). Acute systemic injection (i.p.) of ginseng GS (5-20 mg/kg) significantly elevated both the total and maximum heat production in rats and improved their cold tolerance. However, pretreating the animal with the optimal dose (10 mg/kg) of GS devoid of $Rg_1\;and\;Rb_1$ failed to elicit any beneficial effects in improving cold tolerance. This indicates that either $Rb_1\;and/or\;Rg_1$ may be essential in exemplifying the thermogenic effect of GS. Further studies showed that only pretreating the animals with $Rb_1(2.5-5\;mg/kg),\;but\;not\;Rg_l,$ resulted in an increase in thermogenesis and cold tolerance. In contrast to the acute effect of GS on cold tolerance, enhancement of exercise performance in rats was only observed after chronic treatment (4 days). Further, we were able to demonstrate that both $Rb_1\;and\;Rg_1$ are effective in enhancing aerobic endurance by exercise. To illustrate the beneficial effects of GS in learning and memory, a passive avoidance paradigm (shock prod) was used. Our results indicated that the scopolamineinduced amnesia can be significantly reversed by chronically treating (4 days) the rats with either $Rb_1\;or\;Rg_1$ (1.25 - 2.5 mg/kg). To further examine its underlying mechanisms, the effects of various GS on ${\beta}-amyloid-modulated$ acetylcholine (ACh) release from the hippocampal slices were examined. It was found that inclusion of $Rb_1$ (0.1 ${\mu}M$), but not $Rg_1$, can attenuate ${\beta}-amyloid-suppressed$ ACh release from the hippocampal slices. Our results demonstrated that $Rb_1\;and\;Rg_1$ are the key components involved in various beneficial effects of GS but they may elicit their effects through different mechanisms.

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A Study on the Flight Safety Test of Drones for the Establishment of Toy Drone Safety Standards (완구용 드론 안전기준 재정을 위한 드론의 비행 안전성 테스트 연구)

  • Jin, Jung-Hoi;Kim, Gyou-Beom;Jin, Sae-Young
    • Journal of Convergence for Information Technology
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    • v.9 no.12
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    • pp.141-146
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    • 2019
  • Economic analysis predicts that the drone market will grow, and the growth of the toy and hobby drone market is expected to gradually expand. Drone expectations are rising due to the net economic function of drone market growth, but accidents due to improper management and operations are also increasing. The difference in toy drone performance is incomparably small compared to industrial drone performance, but the ordinary buyer can not know whether the difference can cause an accident during use. The toy drones used in this study were obtained from KC and CE certification, and 20 kinds of drones were used. The flight time ranged from a minimum of 3 minutes to a maximum of 12 minutes, and the control distance ranged from a minimum of 20m to a maximum of 380m. Therefore, it is necessary to secure product safety through sampling inspection of the radio wave output of toy drones, and it is also necessary to mount an algorithm that automatically lowers the altitude or hover when exceeding the limit flight distance. For future research, we will build data to establish toy drone safety standards through a altitude testing and impact testing of toy drone.

K-means clustering analysis and differential protection policy according to 3D NAND flash memory error rate to improve SSD reliability

  • Son, Seung-Woo;Kim, Jae-Ho
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.11
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    • pp.1-9
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    • 2021
  • 3D-NAND flash memory provides high capacity per unit area by stacking 2D-NAND cells having a planar structure. However, due to the nature of the lamination process, there is a problem that the frequency of error occurrence may vary depending on each layer or physical cell location. This phenomenon becomes more pronounced as the number of write/erase(P/E) operations of the flash memory increases. Most flash-based storage devices such as SSDs use ECC for error correction. Since this method provides a fixed strength of data protection for all flash memory pages, it has limitations in 3D NAND flash memory, where the error rate varies depending on the physical location. Therefore, in this paper, pages and layers with different error rates are classified into clusters through the K-means machine learning algorithm, and differentiated data protection strength is applied to each cluster. We classify pages and layers based on the number of errors measured after endurance test, where the error rate varies significantly for each page and layer, and add parity data to stripes for areas vulnerable to errors to provides differentiate data protection strength. We show the possibility that this differentiated data protection policy can contribute to the improvement of reliability and lifespan of 3D NAND flash memory compared to the protection techniques using RAID-like or ECC alone.

A Study on the Corrosion Prevention of the Integral Series Generator for Military Vehicles (군용차량용 엔진일체형 직렬 발전기 부식 방지에 관한 연구)

  • Kang, Tae-Woo;Kim, Seong-Gon;Shin, Cheol-Ho;Lee, Kye-Sub
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.6
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    • pp.74-79
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    • 2019
  • The military vehicle produces electric power through an engine-integrated serial hybrid generator that is connected to the engine and does not have a separate generator installation space. However, depending on the mechanical characteristics of the connection between the generator and the engine, iron oxide for internal rusting and lubrication grew scattered. The iron oxide is adhered to the starter to deteriorate the starting performance, and there is a problem that the noise of the leg due to wear of the gear is increased. To solve this problem, the connection spline material and the surface treatment of the engine were improved and the shape was changed to a grease sealing type to prevent the generation of iron oxide inside. As the shape of the generator connector composing the shafting system was changed, the integrity of the structure was confirmed through the torsional endurance test. In addition, through the actual vehicle load test, it was verified that no corrosion occurred during the target life span without internal corrosion. It was confirmed that the anti-scattering structure of the grease effectively suppresses the generation of iron oxide, thereby reducing the noise generated from the generator. In this paper, we propose a fundamental solution to the degradation of the starter and the noise generation by preventing the back corrosion caused by the serial hybrid generator installed between the engine and the transmission.

Analysis of Priority Factors and Relative Importance about the Components of Rehabilitation Physical Activity Program (재활체육프로그램 구성요인의 상대적 중요도 및 우선순위 분석)

  • Lee, Dong-Chul
    • 재활복지
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    • v.20 no.4
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    • pp.177-201
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    • 2016
  • The purpose of this study is to develop systematical components and implementation of rehabilitation physical activity by analyzing the relative importance among each factor. To achieve the purpose of this study, 20 participants were selected, and they consisted of instructors and adapted physical activity teachers and professional who have experiences in institutes and hospital where have operate program related to rehabilitation physical activity and adapted physical activity program. Delphi technique was conducted for three times by the participants. For the decision of priorities about improvement factors, AHP was performed. The results were as follows. As the result of this study, the factors of the rehabilitation physical activity consisted of six type of exercise; fitness, psychological exercise, aquatic exercise, sense & perception exercise, ambulatory exercise, and motor skills. Also, 21 sub-factors were also extracted. The result from analyzing the priorities of factors was fitness 33.2%, aquatic exercise 20.6%, psychological exercise 16.3%, sense & perception exercise 11.7%, ambulatory exercise 10.8% and motor skills 8.6%. Also, among results from the weighted state of priority factors, muscular strength and endurance were the most importance factor which had 23.4% weighting, and meditation was the least importance factor which had 0.5% weighting.

Changes in Life Habits of Health Associated with Participation in a Wellness Improvement Program in the Elderly (웰니스 건강 증진 프로그램 참여에 따른 고령자 건강생활습관 변화)

  • Shin, Jeong-Hun
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.2
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    • pp.111-121
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    • 2021
  • This study was conducted with the elderly who used a senior welfare center to help their health improvement. After the status of body composition, senior fitness, life habits, and nutrition levels in the elderly were investigated, a wellness health improvement program was conducted for 12 weeks. Effects before and after the program were examined. The following conclusions were drawn. 1. For the changes of body composition by age associated with sex, while elderly men had a significant difference in BMI, elderly women had a significant difference in B.M.I and body fat percentage. 2. For the changes of senior fitness by age associated with sex, while elderly men had a significant difference in lower body muscle, upper body muscle, upper body flexibility, and transformed general endurance, elderly women had a significant difference in lower body muscle and upper body muscle. 3. For the changes of life habits and nutrition levels by age associated with sex, while elderly men had a significant difference in diet habits and exercise habits, elderly women had a significant difference in exercise habits, stress relief habits, and total nutrition level. Based on the findings, the elderly's participation in the wellness improvement program can enhance lower body muscle which is a risk factor of daily activities and fall and increase upper body muscle which is good to carry and move everyday objects. In addition, it may play a positive role in improving diet habits and changing stress relief and exercise habits, resulting in better health and quality of life of the elderly.

The Relationship between Physical Activity Participation, Physical Fitness Level, and Academic Performance in ROTC

  • Jekal, Yoonsuk;Kang, Sang-Min
    • Journal of the Korean Applied Science and Technology
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    • v.39 no.4
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    • pp.568-579
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    • 2022
  • The purpose of this study was to investigate the relationship between physical activity participation habits, physical fitness level, and academic performance among the Reserve Military Training Corps (ROTC). Participants in the current study were 71 ROTCs from J University. Physical activity participation was investigated using the Global Physical Activity Questionnaire (GPAQ), and the level of physical fitness was measured by health-related physical fitness evaluation. For academic performance, university grade data (GPA) was approved by the head of the relevant school district, and the data were collected with the consent of the participants, and each data was analyzed. The correlation between physical activity participation habits, physical fitness level, and GPA was analyzed, and GPA by physical fitness level were compared. This study found that there was no statistically significant correlation between physical activity participation and academic performance. Otherwise, there was a statistically significant correlation between major subjects and total physical fitness score, cardiorespiratory fitness, muscular endurance, flexibility, and body composition. By the level of physical fitness, the ROTCs in the high-physical fitness group showed statistically significantly higher academic performance than the ROTCs in the low-physical fitness group. In addition, low level of physical fitness ROTC group was lower than the other. In conclusion, ROTCs with a high physical fitness level had a positive effect on improving learning ability compared to those who did not. By recommending an autonomous but systematic exercise training program, it is suggested to improve the physical strength of ROTCs and to cultivate excellent future military officers.

Experimental Performance Validation of an Unmanned Surface Vessel System for Wide-Area Sensing and Monitoring of Hazardous and Noxious Substances (HNS 광역 탐지 및 모니터링을 위한 부유식 무인이동체 시스템의 실험적 성능 검증)

  • Jinwook Park;Jinsik Kim;Jinwhan Kim;Yongmyung Kim;Moonjin Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.spc
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    • pp.11-17
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    • 2022
  • In this study, we address the development of a floating platform system based on a unmanned surface vessel for wide-area sensing and monitoring of hazardous and noxious substances (HNSs). For long endurance, a movable floating platform with no mooring lines was used and modified for HNS sensing and monitoring. The floating platform was equipped with various sensors such as optical and thermal imaging cameras, marine radar, and sensors for detecting HNSs in water and air. Additionally, for experiment validation in real outdoor environments, a portable gas-exposure system (PGS) was built and installed on the monitoring system. The software for carrying out the mission was integrated with the Robot Operating System (ROS) framework. The practical feasibility of the developed system was verified through experimental tests conducted in inland water and real-sea environments.

Investigation of Antibody Titers after Inoculation with Commercial Equine Influenza Vaccines in Thoroughbred Yearlings (Thoroughbred 1세말에서 상업용 말 인플루엔자 백신접종 후 항체역가 추적)

  • Yang, J.H.;Park, Y.S.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.20 no.1
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    • pp.89-96
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    • 2018
  • The object of this study was to evaluate the change of antibody titers on virus strains after inoculation with commercial killed equine influenza (EI) vaccines in horses. Serum antibodies of 20 Thoroughbred yearlings were detected using hemagglutination inhibition test for 41 weeks. Second vaccination is inoculated 4 weeks after the initial vaccination. Most of antibody titers were not increased until 4 weeks after first vaccination. The highest titers were detected 6-10 weeks after vaccination. The titers were decreased slowly and maintained for 16 weeks after inoculation. We could barely detect the antibody 41 weeks after vaccination in most cases. Vaccine anergia were appeared in 3 horses (15%) but it depended on virus strains. A/Equine/La Plata/93(H3N8) strain that induce high and durable antibody responses was the most effective among three strains. This study presents the first comprehensive data on the endurance of antibody titers against EI. Our data also suggests that yearlings should be inoculated three times in order to maintaining optimal antibody titers against EI. We speculate the causes of anergia were vaccine break down or individual specificity. Further research is needed to investigate immunological unresponsiveness. This was the first study on strain of equine vaccine in Korea.

Role of Gait Variability and Physical Fitness as a Predictor for Frailty Status in Older Women (여성노인의 허약 상태 예측을 위한 보행변동성 및 체력의 역할 검증)

  • Jin, Youngyun;Park, Jin Kook;Kang, Hyunsik
    • 한국체육학회지인문사회과학편
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    • v.57 no.6
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    • pp.263-272
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    • 2018
  • This study examined the association of gait variability and physical fitness with frailty status in older women. In a cross-sectional design, 168 elderly women, aged 65 years and older (75.07±5.40 years), measured body composition, gait parameters gait variability, physical fitness variables, MMSE-DS and CES-D. Subjects were classified as robust, pre-frail, and frailty based on the Fried et al.(2001) criteria for frailty weight loss, exhaustion, low hand-grip strength, low gait speed, and physical inactivity. Logistic regression analyses were used to determine the odds ratio (ORs) and 95% confidence interval (CI) of frailty status for having gait variability and physical fitness levels. Compared to the robust group (OR=1), the frailty group had significantly higher ORs of having terminal double limb stance (OR=1.48, 95% CI=0.10-2.21, p=.049), step cadence (OR=2.06, 95%CI=1.20-3.43, p=.009) variability, and significantly lower ORs of having upper-strength (OR=0.49, 95%CI=0.31-0.77, p=.002) even after adjusting for age, education, comorbidity, K-IADL, MMSE-KC and CES-D score. The finding of this study suggested that terminal double limb stance, step cadence and upper body muscular strength were independent predictors of frailty.