基于光谱触发的基桩破损检测方法研究

老龄基桩中随着外界的侵袭,会出现老化、破损等问题,进而一旦出现触点粘接、触点松动等症状,会出现较大的隐患。为了解决这一问题,提出了基于光谱触发的基桩破损检测方法,将紫外光敏管作为光电传感器,采集信号经过放大电路与滤波电路后代入一种模糊熵算法,利用模糊熵判断基桩的破损程度,完成基桩的破损检测。系统测试证明,基于光谱触发的基桩破损检测方法技术指标优良,具有很强的实用价值,能够保证基桩破损测试的准确性。     

Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes

Abstract

Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D₂ from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D₂) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D₂ increased serum 25(OH)D₂ by 9.9-fold and decreased serum 25(OH)D₃ by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D₂ increased 25(OH)D₂ with a concomitant decrease in 25(OD)D₃, with no effect on muscular function or exercise-induced muscle damage in high school athletes.     

站姿振动对血液粘度的影响

目的:探讨站姿振动和传统力量训练后,血液粘度的变化特征和生理学机制。方法:运动训练专业21名志愿者,在站姿振动或传统训练条件下,负重深蹲训练12周,测试血液粘度4次。结果:实验组的全血低切粘度、高频低振幅组的全血高切粘度、全血相对粘度和全血高切还原粘度明显增高,均与对照组差异显著。结论:站姿振动使血液粘度增大,其中高频低振幅振动的影响更早、更明显,应科学选择振动训练参数和提高医务监督能力。     

论高校在打击假文凭中的作用

假学历、假文凭对社会的危害比之其它犯罪有过之而无不及,破坏了人才市场公平、公正的竞争规则.从高等学校的角度来讲,片面创收导致学位文凭管理混乱.学历、学位文凭管理上出现的种种问题,虽然还不是大面积的,但严重败坏了党风和社会风气,破坏了高等学历、学位的信用.高校通过加强自身的学籍管理工作,建立完善的导师负责制和导师回避制,配合国家建立证书的多方核对系统等形式在打击假文凭的工作中将能发挥更大的作用.     

Structural Damage Detection with Damage InductionVector and Best Achievable Vector

lintroductionWithtiledevelopmentoftilespaceandnuclearilldustrieselc.,thefuturestructureswillbeordersofmagnitudelargerandmorecomplexthantheirpredecessors.Keepingthosestructuressaferequirestjlattheintegrityoftilestructuresbeperiodicallymollitored.However,th…     

基于模态振型和L1正则化的结构损伤识别

考虑到基于2范数的正则化算法存在对结构识别结果过度光滑的效果,提出了基于模态振与L1正则化的损伤识别方法。以—2D简支梁有限元模型为数值算例,比较了使用不同振型数不同损伤程度对损伤识别效果的影响。数值模拟结果表明,对于多损伤工况,当损伤结构的振型数和无损结构的振型数乘积数大于6时,能较好地进行损伤定位,并能对损伤程度给出定性的描述。     

Numerical Modeling of Response and Damage of Masonry Walls to Blast Loading

To model the damage process of masonry walls under blast loading, a dynamic continuum damage material model is constructed for brick and mortar separately. The degradation of both the stiffness and strength are governed by a damage variable. By using the proposed material model, damage and fragmentation of a typical masonry wall under blast loading at different scaled distances is calculated. The hazard level of the masonry wall to blast loading is evaluated by analyzing the numerical results.     

浅析房屋的破坏性装修

本人在多年的房屋安全鉴定工作中，发现房屋的装修对结构的破坏时有发生。本文就此带来的危害及技术管理上如何杜绝这一现象，谈谈个人看法。     

用动力法对混凝土平面框架结构进行损伤诊断

探讨了采用动力法对混凝土平面框架结构进行损伤诊断的理论，提出了用“残余力向量”判定结构损伤部位，并由此定性地判别结构损伤程度．通过钢筋混凝土框架结构试验表明，该方法简便可行．     

论历史学的科学化

自历史学成为一门独立的学科以来，历史学的科学化一直是史学0家们努力追求的目标，然面，历史学的科学化既给历史学带来了声誉，也给历史学带来了不少损害，如何避免其在科学化过程中所带来的负面影响，是史学界目前面临的主要任务。