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141.
一种基于温差测量原理工作的集成型流量传感器􀀂   总被引:1,自引:1,他引:1       下载免费PDF全文
在比较已有的几种低流速流体的流速流量测量方法基础上,提出一种利用与流速相关温差的测量方案,并用芯片集成方法构成流量传感器加以验证,实验结果与理论预期基本相符.该传感器的主要优点是在低流量条件下具有高灵敏度.  相似文献   
142.
通过对感应同步器位移测量方法的研究,提出了一种以感应同步器为传感器,将软件与硬件有机结合的位移-数字转换新方法。该方法将位移测量功能合理分配,在硬件设计上采用功能强的大规模集成电路,简化系统结构;对于占用硬件资源多而软件上又易实现的功能则直接由软件实现。研究与应用结果表明:利用该方法所设计的宽度测控系统具有测量精度高、结构简单、适应性强等特点,对位移测控系统具有一定的推广价值。  相似文献   
143.
如何对XML文档进行高效的查询,特别是包含查询处理,越来越受到研究界的关注。一种好的XML文档树编码方案可以很好地支持在XML文档上进行包含查询。为了加快XML数据的处理,利用完全二叉树的特性,提出了一种新的编码方案BTC。与区间编码和前缀编码相比,该编码具有简单和长度短的优点,实践证明该编码是有效的。  相似文献   
144.
WDM是Windows平台下新一代的驱动程序模型.本文介绍了用Numega DriverStudio开发WDM设备驱动程序的流程和步骤,简述了驱动程序的生成,调试和安装的方法.针对基于ISA总线的时统卡,详细介绍了WDM驱动程序的开发过程.  相似文献   
145.
利用衰减全反射(ATR)方法进行角度探测,通过改进传统传感器只用单层金属膜激发表面等离子波(SPR)进行探测的结构设计,利用金属包覆波导代替原来的单层的金属膜结构,并从理论上分析了和计算了金属包覆多层ATR生物传感器的检测机理,从而为研制高灵敏度、高解析力的ATR生物传感器提供了理论依据.  相似文献   
146.
粉末溅射有制靶简单、掺杂容易的特点,并有掺杂稳定的优点.利用反溅,发展了粉末溅射,制备了酒敏微型平面薄膜.对薄膜的相关特性进行了研究,给出了薄膜最佳掺杂范围、最佳灵敏度的膜厚以及响应时间与恢复时间随膜厚变化的规律,总结了最优参数.又测试了器件性能,通过实验对影响灵敏度测试的条件如测试电压和湿度影响灵敏度的规律进行了分析和讨论.结论认为,所研制的粉末溅射微型薄膜酒敏器件性能可靠、灵敏度高、稳定性好.  相似文献   
147.
Time between events (TBE) charts are used in high-yield processes where the rate of occurrences is very low. In the current article, we propose a triple exponentially weighted moving average control chart to monitor TBE (regarded as triple exponentially weighted moving average TEWMA-TBE chart) modeled by a gamma distribution. One- and two-sided schemes of the proposed chart are designed and compared with the double EWMA DEWMA-TBE and EWMA-TBE charts. It is shown that the lower- and two-sided TEWMA-TBE charts outperform its competitors, especially for small to moderate downward shifts, while the upper-sided TEWMA-TBE chart has very good detection ability for small shifts. We also study the robustness of the proposed chart when the true distribution is a Weibull or a lognormal and it is found that the TEWMA-TBE chart has better robustness properties than its competitors, especially for small shifts. Two illustrative examples from airplane accidents and earthquakes are also provided to display the application of the proposed chart.  相似文献   
148.
149.
Water-insoluble camptothecin (CPT) congeners are rapidly establishing themselves as promising anticancer drugs. In vitro, they have exhibited: (a) insensitivity to elevated levels of P-glycoprotein that confers multidrug resistance; (b) selective killing of malignant cells traversing the S-phase of the cell cycle, while leaving viable normal cells, which either are arrested at the S-G2 boundary or continue to divide; (c) no cross-resistance with several other anticancer drugs; and (d) potentiation or enhancement of cytotoxicity when appropriately used in combination with tumor necrosis factor, ionizing radiation, and hyperthermia. In addition, development of cell resistance to water-insoluble CPT congeners in vitro is accompanied by increased sensitivity to other anticancer drugs. Furthermore, water-insoluble CPT congeners have exhibited an unprecedented activity against a wide variety of human tumors xenografted in nude mice by inhibiting growth and inducing regression of carcinomas of the lung, breast, ovary, colon, stomach, pancreas, and prostate, as well as malignant melanoma, lymphoma, and leukemia. More importantly, oral administration of the water-insoluble CPT congeners in clinical studies with cancer patients makes other route(s) of administration unnecessary.  相似文献   
150.
In cell or tissue engineering, it is essential to develop a support for cell-to-cell adhesion, which leads to the generation of cell sheets connected by extracellular matrix. Such supports must be hydrophobic and should result in a detachable cell sheet. A thermoresponsive support that enables the cultured cell sheet to detach using only a change in temperature could be an interesting alternative in regenerative medicine. The aim of this study was to evaluate plates covered with thermoresponsive polymers as supports for the formation of fibroblast sheets and to develop a damage-free procedure for cell sheet transfer with the use of membranes as transfer tools. Human skin fibroblasts were seeded on supports coated with a thermoresponsive polymer: commercial UpCell? dishes (NUNC?) coated with thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and dishes coated with thermoresponsive poly(tri(ethylene glycol) monoethyl ether methacrylate) (P(TEGMA-EE)). Confluent fibroblast sheets were effectively cultured and harvested from both commercial PNIPAM-coated dishes and laboratory P(TEGMA-EE)-coated dishes. To transfer a detached cell sheet, two membranes, Immobilon-P® and SUPRATHEL®, were examined. The use of SUPRATHEL for relocating the cell sheets opens a new possibility for the clinical treatment of wounds. This study established the background for implementing thermoresponsive supports for transplanting in vitro cultured fibroblasts.  相似文献   
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