铝合金材质在汽车轻量化中的应用及其成形技术探析

本文简要介绍了汽车轻量化的趋势和铝合金材料的特点,并针对目前汽车生产中的节能减排,降低能耗的的技术要求,探讨了铝合金材质在汽车轻量化中的应用。着重分析了汽车用铝合金零件的铸造成形、压力加工成形,半固态成形以及挤压铸造成形技术。     

强度折减法与极限平衡法对比分析——以安康市一边坡为例

本文通过ABAQUS6.10有限元分析软件,以安康市一边坡治理工程为例,采用有限元强度折减法,求解该边坡稳定性系数,并与极限平衡法进行对比分析.结果表明:边坡在天然工况下,采用有限元强度折减法计算的稳定系数为Fs=1.25～1.59,边坡稳定;采用极限平衡法计算的稳定系数为Fs=1.239～1.578,边坡稳定.     

常用日本钓钩浅析

日本鱼钩的主要特点有三：一是强度高、弹性好;二是钩尖锐利且耐磨;三是防锈性能好。进人我国大陆市场的大部分厂家在日本都有几十年甚至百年历史,制造工艺先进,鱼钩的质量堪称世界一流。但各个厂家对鱼钩的质量侧重点有所不同。由于强度与锐度是相互矛盾的,故有的厂家重视锐度,牺牲一些强度;有的厂家强调强度,可能损失了一些锐度。我们知道相同物质的物体强度是由其截面积所决定的,截面积越大其强度也就越大。以直径0．70毫米的钢丝为例,若直径减少0．03毫米则截面积减少8％左右,强度也随之大幅度减少,故若在材质与制造工艺相…     

伊拉克内燃动车组MAG焊技术研究

本文通过对伊拉克内燃动车组用Q345C钢板进行MAG焊Y型坡口焊接裂纹、拉伸、弯曲、金相等工艺评定试验,选择合适的焊接材料,确定合适的焊接工艺参数及工艺措施,保证焊接质量和接头性能,为制定伊拉克内燃动车组转向架构架的生产制造工艺要求提供试验数据支持。     

伊拉克内燃动车转向架TIG焊技术研究

本文通过对伊拉克内燃动车组用Q345C钢板进行TIG焊Y型坡口焊接裂纹、拉伸、弯曲、金相等工艺评定试验,选择合适的焊接材料,确定合适的焊接工艺参数及工艺措施,保证焊接质量和接头性能,为制定伊拉克内燃动车组转向架构架的生产制造工艺要求提供试验数据支持。     

玩意

①K·SWISS篮球鞋本款以纯白鞋身配以金色五线,中底采用减震功能材料,大底应用超耐磨材质,堪称功能与流行的完美结合。     

建筑模型设计与制作的美学探讨

本文就如何设计与制作出赏心悦目的建筑模型问题,分别从影响建筑模型设计与制作中的几个美学要素;形态、比例要素,材质肌理要素,色彩要素,技艺、环境要素及形式美要素等方面进行了有益的探讨.     

天才设计

设计说明:鞋面由耐磨透气材料和漆皮构成,内有加速鞋带系统,脚踝处采用柔软材料,有效保护脚踝。鞋底有人字纹路分布在受力点上,隐藏前脚掌有碳纤维板,有效支持鞋底,中底采用全长纤维包覆的Phylon材质,形成弹性中底,外底采用磨防滑材料,后脚掌设有lcon魔球系统。     

岛式地铁车站结构地震响应分析

本文针对典型岛式地铁车站结构,建立土-结构动力相互作用有限元计算模型,采用时程分析方法,对车站结构的地震响应及影响因素进行了研究,为同类结构抗震设计提供了参考.     

新农村聚落建筑材质设计的案例研究

在当今经济快速发展、环境危机突出、传统文化流失的大背景下,本文提出了当下新农村聚落建筑设计中材质的运用问题,通过深入的分析研究得出,新农村聚落建筑材质的运用应遵循“就地取材”、“因地制宜”的原则,并在此基础上打造本土氛围,保留和传承其乡土文化。通过一段时间的走访调研和阅读大量文献资料,发现其研究交集上的理论空白和研究价值。本文对新农村聚落建筑设计中材质的运用进行了分析研究,结合农村聚落建筑景观建设的典型案例,归纳总结出聚落建筑材质的类型以及农村聚落建筑材质运用的方法、手段;总结国外新农村聚落建筑材质的运用对我国新农村聚落建筑景观建设的借鉴意义,为我国新农村聚落建筑景观建设指引方向,提供参考。     

Carbohydrate ingestion improves endurance performance during a 1h simulated cycling time trial

This study examined the effect of carbohydrate ingestion on metabolic and performance-related responses during and after a simulated 1h cycling time trial. Eight trained male cyclists (VO 2 peak = 66.5ml kg -1 min -1 ) rode their own bicycles mounted on a windload simulator to imitate real riding conditions. At a self-selected maximal pace, the cyclists performed two 1h rides (separated by 7 days) and were fed either an 8% carbohydrate or placebo solution. The beverages were administered 25 min before (4.5ml kg -1 ) and at the end (4.5ml kg -1 ) of the ride. With carbohydrate feeding, plasma glucose tended (P = 0.21) to rise before the time trial. Compared with rest, the plasma glucose concentration decreased significantly (P < 0.05) at the end of both rides, with no statistically significant difference being observed between treatments. Thereafter, plasma glucose increased significantly (P < 0.05) at 15 and 30 min into recovery, and was significantly higher at 30 min during the carbohydrate trial compared with the placebo trial. No significant changes in plasma free fatty acids were observed during the ride. However, a significant increase (P < 0.05) in free fatty acids was found at 15 and 30 min into recovery, with no difference between trials. Mean power output was significantly (P < 0.05) greater during the carbohydrate compared with the placebo trial (mean - S.E.: 277-3 and 269-3W, respectively). The greater distance covered in the carbohydrate compared with the placebo trial (41.5-1.06 and 41.0–1.06km, respectively; P < 0.05) was equivalent to a 44s improvement. We conclude that pre-exercise carbohydrate ingestion significantly increases endurance performance in trained cyclists during a 1h simulated time trial. Although the mechanism for this enhancement in performance with carbohydrate ingestion cannot be surmised from the present results, it could be related to a higher rate of carbohydrate oxidation, or to favourable effects of carbohydrate ingestion on the central component of fatigue.     

Science and medicine of rowing: A review

The biology and medicine of rowing are briefly reviewed. Effort in a 2000 -m race is about 70% aerobic. Because the boat (and in some instances a cox) must be propelled, successful competitors are very tall, with a large lean mass and aerobic power. Large hearts may lead to erroneous diagnoses of a cardiomyopathy. Large respiratory minute volumes must be developed by chest muscles that are also involved in rowing. The vital capacity is typically large, and breathing becomes entrained. Expiration cannot be slowed relative to inspiration (as normally occurs at high rates of ventilation) and the limiting flow velocity may be reached, with the potential for airway collapse. Performance is strongly related to the power output at the ‘anaerobic threshold’, and lactate measures provide a guide to an appropriate intensity of endurance training. Peak blood lactate levels are higher in males (commonly 11–19 mmol·l -1 and occasionally as high as 25 mmol·l -1) than in females (9–11 mmol·l -1), probably because males have a greater muscle mass in relation to blood volume. The skeletal muscles are predominantly slow twitch in type, developing an unusual force and power at low contraction velocities. Many rowers have a suboptimal diet, eating excessive amounts of fat. Lightweight rowers also have problems of weight cycling. Aerobic power and muscle endurance often change by 10% over the season, but such fluctuations can be largely avoided by a well-designed winter training programme. Injuries include back and knee problems, tenosynovitis of the wrist and, since the introduction of large blades, fractures of the costae.     

我国体育市场管理法规研究

采用调查法和比较法对全国体育市场立法和管理现状进行调查,对部分较早出台并有一定代表性的省市的体育市场管理法规的立法和管理情况进行了研究,提出了体育市场管理立法和管理的原则、基本程序、措施及其一般模式,为规范全国体育市场管理提供参考依据。     

重新认识体育的社会关联

体育与政治之间存在一个悖论，体育的发展与经济实力之间没有直线相关，体育与教育部分重叠，体育与宗教最为近缘，体育可借用科学手段，体育的艺术禀性日益明显，体育与养生反映着两种人生观。     

上海社区体育竞赛参与者的特点探析

本文在专家访谈、问卷调查、数理统计和文献资料分析的基础上,探析了上海社区体育竞赛参与者的特点、参与者对社区体育赛事运作管理的看法等问题。在此基础上从引进社区体育赛事的志愿者、整合社区体育赛事的各种资源、开发社区体育竞赛的无形资产、组建非营利性的专业团队、规范社区体育赛事的服务管理等方面提出了进一步满足上海社区居民日益增长的体育竞赛参赛需求的对策与措施。     

对全面把握游泳训练环节的探讨

从系统观点出发,结合训练实践,对全面把握游泳训练环节进行探讨。认为应强化非智力因素在运动员多年训练中的作用,在育材全过程中不断选材,从整体上把握动态训练的全过程,把培养高水平运动员的整个过程置于一个严格的科学控制之下。     

我国优秀游泳运动员出发技术辅助训练的研究

为改进我国优秀游泳运动员的出发技术,采用观测和实验方法,通过拍摄运动员陆上和水下出发技术录像以及出发计时,对出发技术进行运动生物力学诊断和分析。在此基础上,根据运动员自身特点和不同泳姿提出相应的入水启动方式,并研制出发训练辅助器材,对出发预备姿势、腾起角度以及飞行远度和入水角进行控制。实践证明:这是一种快捷、有效的出发技术辅助训练方法。     

运动性呼吸肌疲劳与耐力性项目的运动能力

影响和限制耐力性运动项目的成绩的生理因素是复杂的和多方面的,取决于训练的强度和运动成绩.大强度持续性运动可导致呼吸肌疲劳.运动性呼吸疲劳可能在决定运动耐量方面起到关键的作用：一方面通过直接影响运动肌力量的生成（外周疲劳）,另一方面,通过肢体用力自感不安反馈引起工作肌运动单位输出功率下降（中枢疲劳）.对呼吸肌进行训练,可能有助于提高耐力性项目的运动成绩.     

Identifying home advantage in international tennis and golf tournaments

A regression analysis of competitors' tournament results in relation to their world rankings was proposed to identify the effect of home advantage in international ‘grand-slam’ tennis and ‘major’ golf tournaments. The results provided little evidence of home advantage in either the grand-slam tennis or the golf tournaments held in 1993. The only possible evidence of home advantage was found in the Wimbledon tennis and the US Open golf championships. Even these findings can be explained, at least partially, by (1) the availability of information concerning the low world rankings of the British tennis players competing at Wimbledon, and (2) selective entry, allowing only the world's top-ranked foreign golfers into the US open golf tournament. In both cases, the lower ranking home competitors have a greater opportunity to perform above their anticipated world rankings. Therefore, provided entry into tennis and golf tournaments is truly ‘open’ to both the host nation's representatives and foreign competitors alike, home advantage does not appear to be a major factor influencing the competitors' performance in such competitions. These findings may be explained by the relatively objective nature of the scoring systems used in tennis and golf, unlike the subjective influence of refereeing decisions on the results of team-games such as soccer.     

对欧洲足球技战术发展趋势的思考

结合欧洲足球技战术的发展特点,就鲁能泰山足球队的体能训练、技术训练、防守阵型、进攻方式、定位球、职业态度、球星培养等诸方面所存在的不足进行了分析,提出相应的改进意见。