共查询到20条相似文献，搜索用时 62 毫秒
1.
2.
3.
4.
5.
6.
陈飞翔;林金星;潘宁 《设备管理与维修》2020,(17):156-157
结合某电厂风机振动信号干扰现象,分析干扰产生的原因,阐述解决风机振动信号干扰问题的整改过程,为同类型机组风机信号干扰诊断、整改提供参考。 相似文献
7.
8.
对硫酸根的测定,干扰物质的消除都是采用将样品酸化并加热除去样品中的碳酸盐。本文提出样品酸化加热时,采用样品煮沸后用消耗样品的体积来进行控制消除碳酸盐的干扰程度,克服了用煮沸时间进行控制消除干扰存在的缺点,保证测定分析成果的准确性和可靠性。 相似文献
9.
一台RZU630型液压薄板拉伸机（合肥锻压机床厂生产）,使用BTL5－E17－M0600－P－S32型微脉冲位移传感器（巴鲁夫公司生产）检测液压垫位置,传感器输出模拟信号通过A／D转换反馈给工控机系统,控制液压垫运行,液压垫行程由工控机软件自由设定,设定升起高度为350mm。 相似文献
10.
11.
高压比往复式压缩机运行质量分析研究 总被引：1，自引：0，他引：1
周凤山 《石油工业技术监督》2008,24(11):25-27
针对温米油田高压缩比、多级往复式压缩机试运行过程中出现的十字头严重烧结等质量问题进行了分析探讨．通过技术改进,解决了机组非正常情况下停机出现的零部件损伤、十子头烧结现象,也为今后机组选型提供了一定的参考。 相似文献
12.
13.
基于隔离机制的竞合效益——以Nike等3组企业为样本的跨案例研究 总被引：1，自引：0，他引：1
本文试图在竞合理论而非竞争理论的范畴内重新解读与进一步研究隔离机制。通过深入案例样本,考察隔离机制的竞合效益在企业经营实践中的存在现象与实际效果,提炼理论观点并据此构建理论模型。在系统的理论推演基础上,深入挖掘隔离机制的竞合效益在垂直竞争维度与水平竞争维度的生成机理,析出与归纳基于差别优势的隔离机制效果——树立纵向障碍的产业保护、获取横向竞争优势与嵌入优势、做强做大产业与市场,并最终实现竞合共生。基于上述研究结论,本文比较分析并指出了隔离机制论与现有竞合理论的根性差异。 相似文献
14.
本文针对计算机绘图中截面交线法这种图形处理方法,在分析计算及消隐理论的基础上提出改进措施,使之不仅具有运算速度快、占用内存少的特点,而且克服了计算机绘图中常见的消隐不彻底的问题,较好地反映了三维立体曲面的图形。并且从不同方位进行动态观察曲面形体的尝试成为可能。 相似文献
15.
16.
17.
A central focus of empirical research in strategic management has been to understand the relationships associated with the structure–strategy–performance paradigm. To examine these relationships, investigators have relied extensively on cross‐sectional methods that embody the implicit assumption that model parameters are stable across firms and over time. Yet, many of the theoretical constructs used in strategic management have clear firm‐ and time‐specific components. Hence, it might be expected that the parameters of the relationships investigated empirically will vary across firms and over time. Whereas recent research has raised concerns about the use of cross‐sectional analysis when parameters vary over time, little attention has been given to the issue of parameter variability across firms. Given the focus of strategy researchers on firm‐level effects and the predominant reliance on cross‐sectional analysis, accounting for across‐firm variability is a significant methodological issue. Failure to account for such variability can lead to biased parameter estimates and incorrect inferences. This paper argues for the adoption of alternative methods that can overcome the limitations of a cross‐sectional analysis and it offers guidance on how researchers can proceed to use these alternative methods to explicitly incorporate or test for variation in model parameters across firms or over time. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
18.
数据包络分析(Data Envelopment Analysis,简称DEA)是评价具有相同类型的多投入和多产出的决策单元是否有效的一种非常有效、简便的方法,已经应用于许多研究领域,如供应商的选择、金融投资等等.但是目前还没有学者将其应用于对投资环境评价中.因此,本文在构造投资环境评价指标体系的基础上,运用DEA方法对区域投资环境进行综合评价.由于投资环境的评价指标众多,直接运用传统DEA方法不能有效区分各个评价地区的投资环境,因此本文运用中性交叉效率DEA模型,从而有效区分各个地区投资环境.最后以沿海9省为例,验证了DEA方法在投资环境评价上的可行性. 相似文献
19.
When designing handling and conveying equipment for combustible dusts, it is crucial to properly implement protective measures (e.g., deflagration venting, suppression, and isolation) capable of mitigating the potential consequences in the event the dust is ignited. Generally speaking, dust processing, storage, and collection equipment, such as cyclones, mills, baghouses, dryers, and silos are typically connected via pipes, pneumatic conveyors, and dust extraction or aspiration lines. If a fire or dust explosion occurs in one vessel, or the interconnecting piping, the flame front or pressure can quickly propagate through these conduits to other parts of the plant and potentially escalate to even worse consequences than the original event. Improper design of isolation devices can be costly, as illustrated by this case study on the fire and explosion in a baghouse that occurred on April 26, 2014 at a plywood manufacturing facility in Texas. More specifically, numerous deficiencies in the system design were identified, which included (1) required air stream flow rates; (2) proper isolation designs; (3) exclusion zones in the anticipated path of a vented deflagration; and (4) impeding deflagration vents. The root cause analysis identified that had a dust hazard analysis been properly performed, these deficiencies would have been identified and the explosion in the baghouse could have been avoided. © 2019 American Institute of Chemical Engineers Process Saf Prog: e12036 2019 相似文献
20.
分离苏云金芽孢杆菌(Bt)晶体蛋白常用的方法有液体双相法、密度梯度法、沉淀法、生物-物理分离法等,但这几种方法各有优缺点。从分离成本、仪器设备、纯度、产量、活性等方面考虑,在超声波处理、悬液制备和紫外线辐射3个方面进行了改进,提出了一种新的分离Bt晶体蛋白的方法,产品纯度可达90％以上,产率从原来的20％提高到28％。... 相似文献