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51.
气流式加速度传感器的敏感机理 总被引:2,自引:0,他引:2
介绍了在研制气流式加速度传感器过程中,为对气流式加速度传感器进行建模,作者对气流式加速度传感器的工作机理进行了理论性探讨。在分析过程中以流体力学、传热学和惯性理论为基础并结合实验结果,建立了适合于气流式加速度传感器的气体运动方程和能量方程。同时还讨论了热线测量加速度的方法及根据实验分析了输入加速度对腔体内温度及传感器输出电压的影响,从而为进一步研究一系列气流式传感器的工作机理提供了方法。 相似文献
52.
We examined the molecular mechanism of metronidazole resistance by constructing a lambda-Zap II phagemid expression library with genomic DNA from a metronidazole-resistance strain of Helicobacter pylori. Twenty-two clones were found to have elevated MTZ resistances in XLOLR strain of E. coli. Phagemids belonging to the twenty two clones were extracted and then retransformed into the XLOLR strain of E. coli. After MTZ selection, five clones could confer metronidazole resistance consistently. According to Southern hybridization and DNA sequencing, the five clones contained a same locus, recA. In addition, transforming the five clones into BL21 strain of E. coli produced a higher resistance to MTZ. Interestingly, electroporation of one of the five phagemid clones into two MTZ sensitive H. pylori yielded MTZ resistant strains. Comparing amino acid sequence in MTZ resistant with sensitive isolates revealed two point mutations at this locus. Above results suggest that mutation in recA may be associated with metronidazole resistance of H. pylori. 相似文献
53.
Jun-Hee Hong Jong-Keun Park 《Power Systems, IEEE Transactions on》1995,10(4):1789-1797
This paper presents a method of obtaining transmission network equivalents from the network's response to a pulse excitation signal. The proposed method is based on modal decomposition representation for the large-scale interconnected system. In this framework we use Prony analysis to identify the network function of the system and to decompose the large system into a parallel combination of simple first-order systems. As a result the network function of the transmission network can be identified easily, and a Thevenin-type of discrete-time filter model can be generated. It can reproduce the driving-point impedance characteristic of the network. Furthermore, the proposed model can be implemented into the EMTP in a direct manner. The simulation results with the full system representation and the developed equivalent system showed a good agreement 相似文献
54.
55.
Cluster analysis in industrial market segmentation through artificial neural network 总被引:6,自引:0,他引:6
Market segmentation has commonly applied cluster analysis. This study intends to make the comparison of conventional two-stage method with proposed two-stage method through the simulated data. The proposed two-stage method is the combination of self-organizing feature maps and K-means method. The simulation results show that the proposed scheme is better than the conventional two-stage method based on the rate of misclassification. 相似文献
56.
Buffer analysis has traditionally relied heavily on the use of traffic models with short range (exponentially decaying) autocorrelation, e.g. Poisson and Markov modulated Poisson processes. Recent literature has suggested the presence of traffic with slowly (hyperbolically) decaying autocorrelation functions; these sources collectively and individually seem to be exhibiting the phenomenon of long range dependence (LRD). Furthermore, it has been claimed that this sort of traffic may exhibit behaviour, when buffered, that is advantageous in that a smaller buffer may be required than would be the case with non-LRD traffic. This phenomenon has been named the crossover effect, and the authors quantify its relevance to ATM networking, using simulation studies of a homogenous mix of chaotic sources. These show that there is a crossover effect, but the key finding is that this effect is much nearer to a buffer length of zero than was predicted by previous theoretical studies, actually occurring at a value so low that it has no practical significance 相似文献
57.
Cheol-Min Park Byung-Hyuk Min Jae-Hong Jun Juhn-Suk Yoo Min-Koo Han 《Electron Device Letters, IEEE》1997,18(1):16-18
We have fabricated a self-aligned offset-gated poly-Si thin film transistor (TFT) by employing a novel photoresist reflow process. The gate structure of the new device is consisted of two unique patterns: A main-gate and a sub-gate. The new fabrication method extends the gate-oxide over the offset region. With the assistance of the sub-gate and reflowed photoresist a self-aligned offset region is successfully obtained due to the offset oxide acting as an implantation mask. The poly-Si TFT with symmetrical offsets is easily fabricated and the new method does not require any additional offset mask step. Compared with the misaligned offset gated poly-Si TFTs, excellent symmetric electrical characteristics are obtained 相似文献
58.
Kwang Soo Lee In Soo Park & Dong Sun Lee 《International Journal of Food Science & Technology》1996,31(1):7-13
The aim of this study was to design a modified atmosphere package for a mixed vegetable salad consisting of 75 g of cut carrot, 55 g of cut cucumber, 20 g of sliced garlic and 50 g of whole green pepper. Respiration data of all the components were combined with film permeability data to predict package atmospheres and design optimal packages for experimental testing for improved shelf-life of the produce. The optimal package avoided minimum O2 and maximum CO2 tolerance limits, and chilling injury temperatures for any component. A pouch form package made of 27 mm low density polyethylene developed a modified atmosphere of 2.0–2.1% O2 and 5.5–5.7% CO2 , which was beneficial for all components and provided better quality retention than other test packages. 相似文献
59.
本文对CIMS装配线和拆卸线的可靠性问题进行研究。文中分析了它们的运行状况,求出了两种生产线的稳态可用度,并用一个例子加以说明。 相似文献
60.
Ovarian mucinous cystadenocarcinoma with mural nodules of anaplastic carcinoma: report of a case and review of the literature 总被引:1,自引:0,他引:1
A decline of cytosol protein kinase C activity was observed in rat myocardial cells at 4 and 8 h after endotoxin administration, and membrane-associated protein kinase C activity rose at the same time. The activity of membrane protein kinase C in aortic smooth muscle cells at 0.5 and 4 h after endotoxin injection was higher than that in control, while cytosol protein kinase C activity was lower. The results indicate that protein kinase C was activated in myocardial cells and aortic smooth muscle cells during various phases of endotoxemia. 相似文献