固定收费路网条件下交通分配的延迟加载算法

路径收费措施是影响道路网络交通分配的重要因素.受出行时间、道路收费及交通拥堵等多种因素的影响,道路使用者会根据自身习惯、偏好及掌握的信息选择不同的出行路径.综合考虑了路径选择过程中确定性因素和随机性因素对时间感知价值的影响,建立了交通分配的变分不等式模型,设计了求解该模型的延迟加载算法,并叙述了该算法的求解过程.算例结...     

深入研究Java的类加载机制

Java类的动态装载机制是Java虚拟机的一项核心技术,可以在运行时刻动态地加载或替换系统的某些功能模块,而不影响系统其它功能模块的正常运行。介绍了Java虚拟机中类的动态装载机制的原理、实现及应用,分析了类装载器的结构、用途,阐述了利用自定义类装载器装载并执行Java类的过程。     

项目导入法在“工程造价”课程教学中的应用研究

根据＂工程造价＂课程实践性较强的特点,教学中引入项目导入法,分析了项目导入法引入的基本条件,详细阐述了项目导入法教学的具体实施步骤,最后总结了运用该教学法应注意的问题。     

The ‘worn-out athlete’: A clinical approach to chronic fatigue in athletes

Chronic fatigue in the athletic population is a common but difficult diagnostic challenge for the sports physician. While a degree of fatigue may be normal for any athlete during periods of high-volume training, the clinician must be able to differentiate between this physiological fatigue and more prolonged, severe fatigue which may be due to a pathological condition. As chronic fatigue can be the presenting symptom of many curable and harmful diseases, medical conditions which cause chronic fatigue have to be excluded. The clinician must then be able to differentiate between chronic fatigue associated with training or chronic fatigue from other medical causes, and also between the chronic fatigue syndrome and the overtraining syndrome. Once the clinician has excluded all of the above medical conditions which cause chronic fatigue in athletes, a significant proportion of fatigued athletes remain without a diagnosis. Novel data indicate that skeletal muscle disorders may play a role in the development of symptoms experienced by the athlete with chronic fatigue. The histological findings from muscle biopsies of athletes suffering from the ‘fatigued athlete myopathic syndrome’ are presented. We have designed a clinical approach to the diagnosis and work-up of the athlete presenting with chronic fatigue. The strength of this approach is that it hinges on the participation of a multidisciplinary team in the diagnosis and management of the athlete with chronic fatigue. The athlete, coach, dietician, exercise physiologist and sport psychologist all play an important role in enabling the physician to make the correct diagnosis.     

红毛五加多糖对解除运动后大鼠骨骼肌疲劳作用的组织化学研究

探讨中药红毛五加多糖对解除骨骼肌疲劳的作用。采用组织化学技术形态定量对运动疲劳大鼠股四头肌不同类型肌纤维的成分进行定量分析。经服中药组恢复后的三种肌纤维类型的糖原含量、琥珀酸脱氢酶(SDH)的活性明显高于疲劳组(P<0.01)。提示红毛五加多糖对解除骨骼肌的疲劳、促进有氧代谢,提高有氧耐力训练水平有重要作用。     

运动、多巴胺与中枢疲劳

该文简要介绍多巴胺递质系统及其主要功能,综述不同负荷运动对中枢多巴胺水平的不同影响作用,认为长时间运动后中枢多巴胺水平的明显降低可能是导致运动性疲劳的重要原因,并就中枢多巴胺水平的变化与运动性疲劳产生的内在机制试作探讨.     

Acute effects of aerobic exercise performed with different volumes on strength performance and neuromuscular parameters

The aim of the present study was to investigate the acute effect of the aerobic exercise volume on maximum strength and strength-endurance performance; and possible causes of strength decrements (i.e. central and peripheral fatigue). Twenty-one moderately trained men were submitted to a maximal incremental test to determine anaerobic threshold (AnT) and maximum dynamic strength (1RM) and strength-endurance (i.e. total volume load [TV]) tests to determine their baseline strength performance. Following, subjects performed six experimental sessions: aerobic exercise sessions (continuous running at 90% AnT) with different volumes (3?km, 5?km or 7?km) followed by 1RM or strength-endurance test in the 45° leg press exercise. Maximum voluntary isometric contraction (MVIC), voluntary activation (VA) level, contractile properties, and electromyographic activity (root mean square [RMS]) of the knee extensor muscles were assessed before and after aerobic exercises and after strength tests. TV was lower after 5?km and 7?km runs than in the control condition (12% and 22%, respectively). Additionally, TV was lower after 7?km than 3?km (14%) and 5?km (12%) runs. MVIC, VA, RMS, and contractile properties were reduced after all aerobic exercise volumes (～8%, ～5%, ～11% and ～6–14%, respectively). Additionally, MVIC, VA, and contractile properties were lower after strength tests (～15%, ～6%, ～9–26%, respectively). In conclusion, strength-endurance performance is impaired when performed after aerobic exercise and the magnitude of this interference is dependent on the aerobic exercise volume; and peripheral and central fatigue indices could not explain the different TV observed.     

The effect of physical contact on changes in fatigue markers following rugby union field-based training

Repeated physical contact in rugby union is thought to contribute to post-match fatigue; however, no evidence exists on the effect of contact activity during field-based training on fatigue responses. Therefore, the purpose of this study was to examine the effect of contact during training on fatigue markers in rugby union players. Twenty academy rugby union players participated in the cross-over study. The magnitude of change in upper- and lower-body neuromuscular function (NMF), whole blood creatine kinase concentration [CK] and perception of well-being was assessed pre-training (baseline), immediately and 24?h post-training following contact and non-contact, field-based training. Training load was measured using mean heart rate, session rating of perceived exertion (sRPE) and microtechnology (Catapult Optimeye S5). The inclusion of contact during field-based training almost certainly increased mean heart rate (9.7; ±3.9%) and sRPE (42; ±29.2%) and resulted in likely and very likely greater decreases in upper-body NMF (?7.3; ±4.7% versus 2.7; ±5.9%) and perception of well-being (?8.0; ±4.8% versus ?3.4; ±2.2%) 24?h post-training, respectively, and almost certainly greater elevations in [CK] (88.2; ±40.7% versus 3.7; ±8%). The exclusion of contact from field-based training almost certainly increased running intensity (19.8; ±5%) and distance (27.5; ±5.3%), resulting in possibly greater decreases in lower-body NMF (?5.6; ±5.2% versus 2.3; ±2.4%). Practitioners should be aware of the different demands and fatigue responses of contact and non-contact, field-based training and can use this information to appropriately schedule such training in the weekly microcycle.     

城市经济综合评价的一个统计方法

利用统计资料 ,对影响各地经济发展的十一项指标进行主成分因子分析 ,用较少的变量来综合代替多个评价指标 ,使较少的变量之间相互独立 ,然后建立经济增长主要依赖指标的线性模型 ,从而对各地区的经济状况进行科学合理的综合评价 .     

肘关节屈伸肌群等速肌力的测定与分析

对27名青年大学生志愿者肘关节进行等速向心测试,探讨肘关节屈、伸肌群在不同运动速度下的峰力矩（PT）、峰力矩比（F／E）、疲劳指数（WF）及其变化情况和性别差异,为今后运动医学、临床医学、康复医学的实践提供参考。结果表明：随速度增加,肘关节屈、伸肌群的PT值皆明显下降,F／E值显著提高;男性在不同测试速度下,肘关节屈伸肌群PT值指标均明显高于女性;不同性别的肘关节F／E值,在慢速测试时,不存在显著性差异,但快速测试中,差异却极显著;男女肘关节屈伸肌群的WF值皆存在差异,但差异不显著。