对称矩阵表达式的极秩及其应用

设对称四元数矩阵表示f1,（X）=A—BXB^＊和f2（X）=A-BX-X^＊B^＊,这里A是埃尔米特或斜埃尔米特矩阵。本文研究了表达式f1（X）1,f2（X）的极大秩和极小秩,这里X满足CXC^＊=D。应用主要结果得到了一四元数矩阵方程组有埃尔米特解的充分必要条件,并给出了四元数矩阵A和B共同的斜埃尔米特广义逆。     

Riesz乘积空间的有关性质

设 { Ei∶i∈I}是一族 Riesz空间且 E= i∈ I　Ei 是 Riesz乘积空间 .关于 Riesz子空间、理想、带、(主 )投影性质、正算子和 Riesz同态 ,指出 E与每一个因子空间 Ei 之间的一些关系 .当 E=C(X)和 Ei=C(Xi) (X和 Xi 为实紧空间 )时 ,还得到 E上 Riesz同态和极大理想的表示形式     

论短跑训练中的最大力量训练与快速力量训练

在短跑的力量训练中目前更多采用快速力量训练法,对最大力量训练法,由于存在认识上的差异,训练中选用较少。最大力量训练法是发展绝对力量和提高肌肉协调力最直接有效的方法。对短跑运动员来说合理运用最大力量训练法,在发展最大力量基础上进而发展快速力量和肌肉协调性,对提高短跑能力和运动成绩是一种经济实用的方法。     

Development and field validation of an omni-domain power-duration model

ABSTRACT

Purpose: To validate and compare a novel model based on the critical power (CP) concept that describes the entire domain of maximal mean power (MMP) data from cyclists.

Methods: An omni-domain power-duration (OmPD) model was derived whereby the rate of W? expenditure is bound by maximum sprint power and the power at prolonged durations declines from CP log-linearly. The three-parameter CP (3CP) and exponential (Exp) models were likewise extended with the log-linear decay function (Om3CP and OmExp). Each model bounds W? using a different nonconstant function, W?eff (effective W?). Models were fit to MMP data from nine cyclists who also completed four time-trials (TTs).

Results: The OmPD and Om3CP residuals (4 ± 1%) were smaller than the OmExp residuals (6 ± 2%; P < 0.001). W?eff predicted by the OmPD model was stable between 120–1,800 s, whereas it varied for the Om3CP and OmExp models. TT prediction errors were not different between models (7 ± 5%, 8 ± 5%, 7 ± 6%; P = 0.914).

Conclusion: The OmPD offers similar or superior goodness-of-fit and better theoretical properties compared to the other models, such that it best extends the CP concept to short-sprint and prolonged-endurance performance.     

有氧代谢能力的应用及机制

从多层次、不同途径较系统地研究影响最大有氧代谢能力的生理学因素及最大摄氧量在运动训练中的应用。结果发现:少年运动员的最大摄氧量与疲劳主观感觉有关,其最大摄氧量负荷时的R.P.E值低于成年人;不同负荷形式测定的最大摄氧量值有较大的差异,按其大小排列顺序为:固定跑台、功率自行车、台阶;耐力训练可提高有氧代谢水平,特别是无氧阈值或最大摄氧量利用率;在白、黄、黑肤色人种中,最大摄氧量值无种族差异;在力竭性运动中,线粒体钙聚积抑制细胞呼吸,可造成有氧代射能力下降。     

我国优秀女子短跑道速滑运动员最大有氧能力及通气阈的追踪研究

最大摄氧量和通气阀作为衡量运动员耐力水平的指标已被广泛地应用于运动实践。对1987～1990年我国短跑道女子速滑运动员各个训练时期的最大摄氧量和通气阈进行了追踪研究。发现1987年的陆地训练能明显提高了运动员的有氧代谢能力。而且我国选手的最大摄氧量也高于国内外一些速度滑冰选手;通气阈在各个训练时期有训练均有明显的提高,所以,通气阈是评定短跑道速度滑冰运动员耐力水平的一个重要指标,通气阈的训练是提高耐力能力的重要训练手段,它优于最大摄氧最的训练。     

关于环的Herstein猜测

本文讨论了结合环的Herstein猜测,得到了Herstein猜测成立的若干条件。     

Bernoulli方程的一个极大类型

给出形如dydx=P(x)M(y) +Q(x)N(y)的微分方程的线性化条件 ,讨论了Bernoulli方程、Riccati方程的线性化问题 ,从而将Bernoulli方程扩大到一个极大类型     

Pr阶循环群的整群环的极大Z-序

对pr阶循环群讨论了它们的整群环ZG在QG中的极大的Z-序Γ,给出了Γ的具体表达式。     

Creatine co-ingestion with carbohydrate or cinnamon extract provides no added benefit to anaerobic performance

The insulin response following carbohydrate ingestion enhances creatine transport into muscle. Cinnamon extract is promoted to have insulin-like effects, therefore this study examined if creatine co-ingestion with carbohydrates or cinnamon extract improved anaerobic capacity, muscular strength, and muscular endurance. Active young males (n?=?25; 23.7?±?2.5?y) were stratified into 3 groups: (1) creatine only (CRE); (2) creatine+ 70?g carbohydrate (CHO); or (3) creatine+ 500?mg cinnamon extract (CIN), based on anaerobic capacity (peak power·kg^?1) and muscular strength at baseline. Three weeks of supplementation consisted of a 5?d loading phase (20?g/d) and a 16?d maintenance phase (5?g/d). Pre- and post-supplementation measures included a 30-s Wingate and a 30-s maximal running test (on a self-propelled treadmill) for anaerobic capacity. Muscular strength was measured as the one-repetition maximum 1-RM for chest, back, quadriceps, hamstrings, and leg press. Additional sets of the number of repetitions performed at 60% 1-RM until fatigue measured muscular endurance. All three groups significantly improved Wingate relative peak power (CRE: 15.4% P?=?.004; CHO: 14.6% P?=?.004; CIN: 15.7%, P?=?.003), and muscular strength for chest (CRE: 6.6% P?P?P?P?P?P?P?=?.013; CHO: 10.0% P?=?.007; CIN: 17.3% P?P?=?.021) and CIN (15.5%, P?相似文献