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覆膜机新型加热辊有限元分析
The Research and Analysis of Heating Method of Laminating Machine Based on Finite Element
 [PDF]

, 郭楠, 杨培克, 王岩, 王晓华, 赵世英
Instrumentation and Equipments (IaE) , 2014, DOI: 10.12677/IaE.2014.21001
Abstract:

覆膜机是通过在承印材料上压上一层薄膜来提高产品的美观及保护效果的印后设备。加热系统是覆膜设备重要的功能单元之一,选择合适的温度及系统的补温性能对覆膜效果影响很大。目前,市场上覆膜机加热方式多种多样,其中最常用的方式之一为导热油循环系统,但流体性质容易变化,导致加热效果不稳定,结果很难预测。提出了热力学分析及计算方法,通过有限元分析,建立不同温度下导热油加热系统的模型,通过分析求解,得到热辊表面的温度变化规律曲线,提出了一种新型的加热方式,并对其做了相应的热力学分析。
Laminating machine is a kind of post-print equipment that presses a thin film on printing materials to improve the aesthetic and protective effect of product. The heating system is one of the important functional units of laminating machine. It has a great effect on laminating effect to select the appropriate temperature and the complement temperature performance of the system. Currently, there is a variety of heating methods of laminating machine in the market, the most common one of which is conducting oil circulation system, but the fluid properties easily change; that leads to the instability heating effects, therefore, it’s difficult to predict the results. This paper establishes the different temperature model of oil heating system, analyses and solves the surface temperature variation of heating cylinder by the finite element. In addition, it also proposes a new type of heating method, and then it makes the corresponding thermodynamic analysis.

非煤矿山采空区失稳机理及稳定性数值模拟分析
段瑜,赵培,,赵云
安全与环境工程 , 2014,
Abstract: 地下开采形成的采空区而引起的灾害已成为地下矿山主要灾害之一。本文从非煤矿山采空区顶板(连续性结构岩体层状顶板、非连续性碎裂结构岩体)和矿柱两个关键影响要素对采空区失稳机理进行了研究,同时结合工程实例,采用FLAC3D软件对采空区稳定性进行了数值模拟计算与分析。结果表明采空区围岩受力及变形导致的失稳状况与理论计算相吻合,并在工程上得到了很好的验证和应用。
小流域堰塞湖对山洪泥石流的调控模式探讨
陈宁生,胡桂,宪阳,,苏立
人民长江 , 2015,
Abstract: ?通过对我国青藏高原东缘小流域堰塞湖系统调查与分析,选择金沙江一级支流巧家县的海子沟、岷江一级支流茂县的宗渠沟和岷江二级支流理县的古城沟作为典型案例,进行小流域堰塞湖对山洪泥石流的调控模式研究。研究得出,小流域堰塞湖调节作用下山洪泥石流的相互转换模式主要有3类:①淤积与再侵蚀产生泥石流模式;②淤积与清水出流模式;③侵蚀规模放大模式。基于小流域堰塞湖对山洪泥石流调控特征分析,揭示不同特征的小流域堰塞湖成灾风险,并提出针对性的处理措施。
基于TMS320VC5410的声信号采集与实时回放系统
An Audio Signal Acquisition and Real-Time Playing System Based on TMS320C5410
 [PDF]

, 马朝
Journal of Electrical Engineering (JEE) , 2013, DOI: 10.12677/jee.2013.12014
Abstract: 本文介绍了一种基于TMS320VC5410的实时语音信号采集与实时回放系统。介绍了整个系统的总体设计方案和软、硬件的设计。通过软件编程实现音频信号的采集与回放,并通过对一个实例效果分析,证明了本系统所采集的信号具有高保真度。
This paper puts forward an audio signal acquisition and real-time playing system based on TMS320C5410. It introduces the designing methods of the whole system, the software and the hardware. The audio signal acquisition and the real-time playing are completed with the software program. The result proves that the signals have high fidelity by analyzing a sample.
转录因子DREB1A基因和Bar基因双价植物表达载体的构建及对马铃薯遗传转化的研究
贾小霞,恩芳,王一航,文国宏,龚成文,王红梅,李建武,,胡新
草业学报 , 2014, DOI: 10.11686/cyxb20140312
Abstract: 马铃薯在生长发育过程中受各种生物和非生物胁迫的影响,干旱是其中最常见和危害最严重的非生物胁迫因素之一,常常导致单产不高,总产不稳,严重影响着马铃薯产业的发展。本研究以改善马铃薯抗旱性为目的,采用PCR方法从拟南芥中克隆了转录因子DREB1A基因和诱导型启动子rd29A。利用DNA重组技术成功构建了诱导型启动子rd29A驱动转录因子DREB1A基因和CaMV35S启动子驱动Bar基因的双价植物表达载体pBI121-rd29-BDR,并通过农杆菌介导法对马铃薯进行遗传转化,PPT筛选得到22株抗性苗,PCR和RT-PCR检测证明DREB1A基因已整合到陇薯10号马铃薯基因组中并在转基因植株中转录表达,有望提高转基因马铃薯的抗旱性。目前,作者正在进行转基因马铃薯的抗旱性分析研究。
激光汽化术与前列腺电切术治疗良性前列腺增生疗效的Meta分析*
张晓波,陈明泉,陈雄,,观南,董超,白耀,谭新骥,谷杰,,李东杰
- , 2017, DOI: 10.3969/j.issn.1007-1989.2017.07.004
Abstract: 摘要: 目的??系统评价经尿道980nm激光汽化术与前列腺电切术(TURP)治疗良性前列腺增生(BPH)的疗效。方法?收集国内外关于经尿道980nm激光汽化术与TURP治疗BPH的文献,采用Revman 5.3软件进行Meta分析。结果?筛选后共6篇文献符合纳入标准,总计839例,其中包括980nm激光治疗组450例和TURP组389例。Meta结果显示:和TURP组相比,980nm激光组手术时间差异无统计学意义[标准化均数差(SMD)=0.11,95%CI(-0.52,0.74),P >0.05],住院时间较短[SMD=-1.95,95%CI(-3.42,-0.48),P <0.05]及术后尿管留置时间较短[SMD=-2.64,95%CI(-3.92,-1.36),P <0.05]。980 nm激光组和TURP组在术后国际前列腺症状评分(IPSS)差异无统计学意义[加权均数差(WMD)=0.12,95%CI(-0.27,0.51),P >0.05],术后生活质量评分(QOL)评分差异无统计学意义[SMD=0.00,95%CI(-0.57,0.57),P >0.05],术后最大尿流率(Qmax)差异无统计学意义[SMD=0.06,95%CI(-0.26,0.37),P >0.05]。结论?980nm激光治疗良性BPH与经典的TURP术式相比,在住院时间和术后尿管留置时间方面有优势,远期效果无明显差异。
Abstract: Objective?To systematically review and evaluate the perioperative indicators and surgical curative effect of 980 nm diode laser vaporization of prostate and transurethral resesction of prostate (TURP) in treating benign prostatic hyperplasia (BPH).?Methods?Retrieved published comparative studies 980 nm diode laser vaporization of prostate versus transurethral resesction of prostate in treating benign prostatic hyperplasia, and pooled the data from eligible studies. The statistical analysis was performed using Revman 5.3 software.?Results?Six trials including 839 patients were eligible to the criteria (450 in 980 nm diode laser group and 389 in TURP group). The baseline of patients characteristics were comparable in all the studies. Meta analysis showed that: the operative time was not significantly different between the 980 nm diode laser group and TURP group [SMD = 0.11, 95 ~ CI (-0.52, 0.74), P > 0.05]; Compared with TURP group, 980 nm diode laser group has shorter hospital stays [SMD = -1.95, 95%CI (-3.42, -0.48), P < 0.05], and shorter catheterization time [SMD = -2.64, 95%CI (-3.92, -1.36), P < 0.05]. There was no significant difference between IPSS [WMD = 0.12, 95%CI (-0.27, 0.51), P > 0.05], QOL [SMD = 0.00, 95%CI (-0.57, 0.57), P > 0.05] and Qmax [SMD = 0.06, 95%CI (-0.26, 0.37), P > 0.05].?Conclusion?980 nm diode laser vaporization of prostate is safe and effective in treating benign prostatic hyperplasia, and compared with TURP, it has advantages in shorter hospital stays and shorter catheterization time.
拟南芥诱导型启动子rd29A的克隆及其功能鉴定
恩芳,贾小霞,,文国宏,胡新,龚成文,王一航,李建武
- , 2015, DOI: 10.7606/j.issn.1000-7601.2015.04.43
Abstract: 以改善作物抗旱性为目的,采用PCR方法从拟南芥中克隆了诱导型启动子rd29A,序列分析发现克隆的rd29A启动子与已发表的rd29A启动子序列(D13044)的同源性为99.47%。利用DNA重组技术成功构建了rd29A启动子驱动GUS基因的植物表达载体pBI121-rd29-GUS,并通过农杆菌介导法转化烟草,转基因烟草叶片中GUS酶活性的组织化学检测结果表明,rd29A启动子能驱动目的基因的有效表达。因此,可以在后续的马铃薯抗旱转基因研究中直接应用。
某工程单层球面网壳结构的稳定性研究

工业建筑 , 2001, DOI: 10.13204/j.gyjz200102016
Abstract: 采用自编结构非线性分析程序,对某工程肋环形单层球面网壳结构就两种主要工况(竖向静力荷载组合作用及风荷载组合作用)进行了失稳全过程分析,得到结构多条失稳路径。结果表明,结构的几何缺陷将严重影响结构的失稳形式,从而影响结构的极限承载能力。
免疫多向二进制粒子群优化算法
Immune Multi-Direction Binary Particle Swarm Optimization Algorithm
 [PDF]

, 张进秋, 岳杰, 马朝
Computer Science and Application (CSA) , 2013, DOI: 10.12677/CSA.2013.38058
Abstract:
提出了一种新的BPSO改进算法——免疫多向二进制粒子群优化算法(IMBPSO),算法中引入了免疫算法的克隆选择算子和免疫系统的免疫记忆特性,保证了算法寻优的快速性以及群体的多样性。此外,通过修改速度更新公式,把粒子群的搜索方向从单向变为多向,从而克服了BPSO算法中易陷入局部最优,进化后期收敛速度慢和精度不高等缺点。通过几个标准函数进行测试与评价,证明了IMBPSO算法具有良好的寻优性能。
>A novel algorithm of BPSO is presented, which is named immune multi-direction binary particle swarm op- timization algorithm (IMBPSO). Operators including immune memory and clone selection of immune algorithm are introduced into BPSO in order to ensure the algorithm to find the best solution quickly and the diversity of colony. Fur- thermore, by modifying the formula of renewal of speed, the particle is translated from single direction into multi-di- rection. So it overcomes the disadvantages of BPSO algorithm, including falling into local best easily, low convergence speed as well as low quality in evolution evening. By testing and estimating with some standard functions, IMBPSO algorithm’s ability in finding the best solution is proved.
装备故障预测与健康管理体系结构及其关键技术研究
Research on Architecture and Key Technology of Fault Prognostics and Health Management for Equipment
 [PDF]

, 张进秋, 马朝
Artificial Intelligence and Robotics Research (AIRR) , 2013, DOI: 10.12677/AIRR.2013.24018
Abstract:
故障预测和健康管理(PHM)技术是复杂的装备系统采用的便于测试和维修诊断的一种革新方案,是实现其经济可承受性的关键技术,本文结合PHM技术在降低装备保障维修费用方面的明显优势,在深入探讨了PHM技术的概念和内涵的基础上,建立了PHM系统的开放式体系结构框架,并对框架中包含的七个模块进行了分析;概述了PHM技术的研究和应用现状,重点研究了实现装备故障预测与健康管理的关键技术和主要实现方法,包括传感器与信号处理技术、故障诊断与状态监测技术、健康性能评估技术、状态预测技术和智能决策和健康管理技术等,最后总结了PHM技术的特点和发展趋势。
>Fault prognostics and health management (PHM) technology is an innovative solution for the complex equipment system which is convenient to test and repair in the diagnosis and it is the key technology to achieve economic affordability. Combining the advantage of PHM technology in reducing equipment maintenance costs, on the basis of discussing the concept and connotation of PHM technology, this paper establishes and analyzes open architecture framework which contains seven modules for PHM system. Also, PHM technology research and application are summarized with the focus on the implementation method and key technology for equipment PHM, including the sensor and signal processing technology, fault diagnosis, condition monitoring technology, health & performance evaluation technology, condition forecasting technology, intelligent decision technology and health management technology, etc. Finally, the characteristics and development trend of PHM technology are summarized.
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