Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacit...Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacity of elite Congolese karate athletes, as well as their haemodynamic and blood lactate concentrations responses changes during Ruffier test and stimulated competition. Methods: Twelve karate athletes (6 seniors and 6 juniors) took part in the study. These karate athletes were selected within the national karate teams (senior and junior) of Congo-Brazzaville. Anthropometric, bioenergetic and haemodynamic (HR, SBP, DBP) parameters and blood lactate [La] concentrations were measured at rest, immediately after the end of Ruffier test and each fight (n = 3). Results: Peak aerobic power (PAP) and maximum oxygen uptake (VO2 max) values averaged 437 ± 23 watts and 57.61 ± 2.2 ml/kg/mn, values varying as function as age division (senior vs junior). The recovery index was 5.4 ± 3.4 for juniors and 6.8 ± 3.2 for seniors. SBP, HR and [La] concentrations increased significantly during fights, compared to the resting values. HRmax was 182.3 ± 1.6 bpm (89% theoretical HRmax) for seniors and 182.0 ± 13.5 bpm (86% theoretical HRmax) for juniors. Peak [La] concentrations were 10.3 ± 1.5 mmol/l for seniors and 10.8 ± 1.2 mmol/l for juniors. Conclusion: Congolese karate athletes call upon high levels of the anaerobic and aerobic capacities. The karate training program in Congo should emphasize more gold improvising lower body anaerobic power and endurance.展开更多
Current climate challenges and energy concerns have urged scientists, researchers, and governments to take action in order to reduce carbon footprint and energy consumption. Considering the growing need for energy sup...Current climate challenges and energy concerns have urged scientists, researchers, and governments to take action in order to reduce carbon footprint and energy consumption. Considering the growing need for energy supplies, the reliability and sustainability of power plants are another area of concern for communities. Since building is among the major consumers of electricity (almost 40%), the energy management strategies have been substantially focused on demand side management and building operation system. Energy efficiency, peak-load management, and demand response are among the most outstanding and widespread practices in order to reduce building energy consumption and peak demand. Smart grids and smart meters are considerably gaining the attention of policy makers in most developed and developing countries. This paper will revolve around these outstanding energy management strategies and technologies and their merits and drawbacks in the journey of current communities towards sustainability.展开更多
Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected ...Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes. μLaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of μLaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes.展开更多
For rate control (RC) of hierarchical structure coding, an independent rate-quantization (R-Q) model was proposed based on mean absolute differences (MADs) in different temporal levels (TLs). In the proposed R-Q model...For rate control (RC) of hierarchical structure coding, an independent rate-quantization (R-Q) model was proposed based on mean absolute differences (MADs) in different temporal levels (TLs). In the proposed R-Q model, a novel MAD model was developed according to the hierarchical structure. The experimental results demonstrate that the proposed algorithm provides better performance, in terms of average peak signal-to-noise ratio (PSNR) and quality smoothness, than the H.264 reference model, JM14.2, under various sequences.展开更多
颗粒混凝土材料在建筑结构中应用比较常见,但其冲击下的动力学性能研究欠缺.为得到颗粒混凝土的动力学特性,借助MTS实验机得出其静力学强度,其后使用直径为75 mm SHPB系统对颗粒混凝土试样做了多种加载速度下的冲击试验.结果表明,颗粒...颗粒混凝土材料在建筑结构中应用比较常见,但其冲击下的动力学性能研究欠缺.为得到颗粒混凝土的动力学特性,借助MTS实验机得出其静力学强度,其后使用直径为75 mm SHPB系统对颗粒混凝土试样做了多种加载速度下的冲击试验.结果表明,颗粒混凝土试样的毁坏模式是非脆性碎裂,呈现出延性特点;随着冲击速度的增大,破坏后的形状由试样被压扁(形态基本完整,表现出明显的可压缩性)过渡到絮状.应变率在103.88~464.71 s^(-1)时,试样的峰值应力随着应变率的变大而增大,表现出明显的应变率效应.根据实验现象和实验数据进行分析,推导建立了颗粒混凝土峰值应力前和峰值应力后应力-应变的等效本构方程,将实验数据与拟合数据进行对比,具有较为明显的一致性,验证了本构方程的准确性.展开更多
文摘Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacity of elite Congolese karate athletes, as well as their haemodynamic and blood lactate concentrations responses changes during Ruffier test and stimulated competition. Methods: Twelve karate athletes (6 seniors and 6 juniors) took part in the study. These karate athletes were selected within the national karate teams (senior and junior) of Congo-Brazzaville. Anthropometric, bioenergetic and haemodynamic (HR, SBP, DBP) parameters and blood lactate [La] concentrations were measured at rest, immediately after the end of Ruffier test and each fight (n = 3). Results: Peak aerobic power (PAP) and maximum oxygen uptake (VO2 max) values averaged 437 ± 23 watts and 57.61 ± 2.2 ml/kg/mn, values varying as function as age division (senior vs junior). The recovery index was 5.4 ± 3.4 for juniors and 6.8 ± 3.2 for seniors. SBP, HR and [La] concentrations increased significantly during fights, compared to the resting values. HRmax was 182.3 ± 1.6 bpm (89% theoretical HRmax) for seniors and 182.0 ± 13.5 bpm (86% theoretical HRmax) for juniors. Peak [La] concentrations were 10.3 ± 1.5 mmol/l for seniors and 10.8 ± 1.2 mmol/l for juniors. Conclusion: Congolese karate athletes call upon high levels of the anaerobic and aerobic capacities. The karate training program in Congo should emphasize more gold improvising lower body anaerobic power and endurance.
文摘Current climate challenges and energy concerns have urged scientists, researchers, and governments to take action in order to reduce carbon footprint and energy consumption. Considering the growing need for energy supplies, the reliability and sustainability of power plants are another area of concern for communities. Since building is among the major consumers of electricity (almost 40%), the energy management strategies have been substantially focused on demand side management and building operation system. Energy efficiency, peak-load management, and demand response are among the most outstanding and widespread practices in order to reduce building energy consumption and peak demand. Smart grids and smart meters are considerably gaining the attention of policy makers in most developed and developing countries. This paper will revolve around these outstanding energy management strategies and technologies and their merits and drawbacks in the journey of current communities towards sustainability.
文摘Peak to Average Power Ratio (PAPR) is defined as the instantaneous power (maximum value) to the average power ratio. PAPR is considered to be a major problem in OFDM systems. This problem can cause radical unexpected behavior of the signal fluctuation. This fluctuation is constituted by a large number of power states. The enormous number of these states leads to an additional complexity of ADCs and DACs. This research addresses the previous problem in OFDM systems utilizing Turbo Codes. μLaCP technique is employed for the purpose of decreasing PAPR. Moreover, our OFDM system was simulated in the presence of an AWGN channel with four types of codes (without the presence of ADCs and DACs). These were constituted of PCCC (typical and new), SCCC, and Convolutional Codes. Our Turbo Coded OFDM exhibited unchanged BER performance before and after the use of μLaCP technique. This was accomplished by modifying our previous PAPR reduction technique without sacrificing greatly its attributes.
基金National Natural Science Foundations of China (No. 60972035,No. 61074009)Natural Science Foundation Program of Shanghai,China ( No. 10ZR1432800)
文摘For rate control (RC) of hierarchical structure coding, an independent rate-quantization (R-Q) model was proposed based on mean absolute differences (MADs) in different temporal levels (TLs). In the proposed R-Q model, a novel MAD model was developed according to the hierarchical structure. The experimental results demonstrate that the proposed algorithm provides better performance, in terms of average peak signal-to-noise ratio (PSNR) and quality smoothness, than the H.264 reference model, JM14.2, under various sequences.
文摘颗粒混凝土材料在建筑结构中应用比较常见,但其冲击下的动力学性能研究欠缺.为得到颗粒混凝土的动力学特性,借助MTS实验机得出其静力学强度,其后使用直径为75 mm SHPB系统对颗粒混凝土试样做了多种加载速度下的冲击试验.结果表明,颗粒混凝土试样的毁坏模式是非脆性碎裂,呈现出延性特点;随着冲击速度的增大,破坏后的形状由试样被压扁(形态基本完整,表现出明显的可压缩性)过渡到絮状.应变率在103.88~464.71 s^(-1)时,试样的峰值应力随着应变率的变大而增大,表现出明显的应变率效应.根据实验现象和实验数据进行分析,推导建立了颗粒混凝土峰值应力前和峰值应力后应力-应变的等效本构方程,将实验数据与拟合数据进行对比,具有较为明显的一致性,验证了本构方程的准确性.
