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81.
基于DSP的电力数据采集平台的设计与研究   总被引:1,自引:0,他引:1  
介绍了一种用于电力系统的数据采集系统.该系统采用数字信号处理器(DSP)和复杂可编程逻辑器件(CPLD)作为核心芯片,给出了主要部分的电路及其原理、功能,系统中使用CPLD实现基本逻辑,使系统有足够的冗余和灵活性,具有可靠性高、可升级等优点.  相似文献   
82.
基于DTW算法的语音识别系统实现   总被引:10,自引:0,他引:10  
动态时间归整(DTW)算法的实现简单有效,在孤立词语音识别系统中得到了广泛的应用.介绍了将DTW算法移植到TMS320VC5402上实现孤立词语音识别的原理、系统硬件组成和软件设计.研究结果表明,系统能满足实时性能要求,识别效果良好.  相似文献   
83.
Total conceptual cost estimates and the assessment of the quality of these estimates are critical in the early stages of a building construction project. In this study, the support vector machine (SVM) model for assessing the quality of conceptual cost estimates is proposed, and the application of SVM in construction areas is investigated. The results show that the SVM model assessed the quality of conceptual cost estimates slightly more accurately than the discriminant analysis model. This shows that using the SVM has potential in construction areas. In addition, the SVM model can assist clients in their evaluation of the quality of the estimated cost and the probability of exceeding the target cost, and in their decision on whether or not it is necessary to seek a more accurate estimate in the early stages of a project.  相似文献   
84.
钛合金植入物材料的表面改性研究进展   总被引:1,自引:0,他引:1  
简介了钛合金植入物材料的开发及表面改性技术。  相似文献   
85.
根据双点后方交会的图形特点和已知条件,列出了方程组,推导出了双点后方交会直接计算座标的简便公式,同时求出了精度计算公式,以供测量人员参考  相似文献   
86.
Rh/Lil/SnR4 is an effective catalyst system for the conversion of methyl formate to acetic acid under carbon monoxide pressure. The effects of solvent and initial CO partial pressure on the turnover rate of the reaction were investigated. The possibility of replacing some of the iodide promoters by tin compounds has been probed.  相似文献   
87.
HYDRODYNAMIC FORCE ON SMOOTH HORIZONTAL CYLINDER IN UNIFORM OSCILLATORY FLOWHYDRODYNAMICFORCEONSMOOTHHORIZONTALCYLINDERINUNIF...  相似文献   
88.
The present study determined tumorigenicity, tumor classification and DNA damage induced in infant mice by benzo[a]pyrene (B[a]P) or Manufactured Gas Plant (MGP) residues after a single exposure. Male and female B6C3F1 mice were exposed to B[a]P or MGP residue from a single environmental site (MGP-4) and males were also exposed to MGP residue composite from seven different sites (MGP-M7). At 26, 39 and 52 weeks after exposure tumorigenesis was assessed in lung, forestomach and liver. Formation and persistence of DNA adducts were quantified by 32P-postlabeling. Exposure of males to B[a]P induced liver tumors in a dose and time dependent manner. MGP induced more advanced tumors than B[a]P. Only a single liver tumor was found in MGP-4 treated females. No forestomach and few pulmonary adenomas were induced in males or females. MGP-4, MGP-M7 or B[a]P induced DNA adducts in males and females. Adducts in liver, lung and forestomach peaked on different days and decreased at different rates. At 24 h post-exposure, no significant differences in initial DNA adduct levels occurred in males and females exposed to MGP-4 or B[a]P. Lack of DNA damage (adducted DNA) did not account for non-responsiveness of lung and forestomach in B6C3F1 genders as well as in liver in females. MGP tumorigenicity could not be accounted for solely by B[a]P content nor did it reflect additivity of B[a]P and other carcinogenic polycyclic aromatic hydrocarbons (PAHs) in MGP. Synergy among MGP-PAHs, presence of unidentified carcinogens and/or promoters in MGP may account for MGP potency. The B6C3F1 infant male model is a convenient and rapid assay for assessing MGP liver tumorigenicity and potency.  相似文献   
89.
A boron-doped diamond field emitter diode with ultralow turn-on voltage and high emission current is reported. The diamond field emitter diode structure with a built-in cap was fabricated using molds and electrostatic bonding techniques. The emission current versus anode voltage of the capped diamond emitter diode with boron doping, sp2 content, and vacuum thermal electric (VTE) treatment shows a very low turn-on voltage of 2 V. A high emission current of 1 μA at an anode voltage of less than 10 V can be obtained from a single diamond tip. The turn-on voltage is significantly lower than comparable silicon field emitters  相似文献   
90.
BACKGROUND: The deteriorating cardiac function of patients with chronic anemia may be improved with transfusion. The effect of transfusion on cardiac function was evaluated in patients with chronic anemia. STUDY DESIGN AND METHODS: In a prospective study, ejection fraction (EF) was determined before and after transfusion in 41 patients with chronic anemia. The results were compared and analyzed. RESULTS: The volume of red cells transfused and the levels of pretransfusion hemoglobin, hematocrit, and red cell, white cell, and platelet counts did not affect the posttransfusion EF, whereas the pretransfusion EF of the right or left ventricle inversely affected the posttransfusion change in EF in the respective ventricle (p < 0.001 and r = -0.5022; p = 0.01 and -0.3917, respectively). There was no significant difference in the change in EF in the right and left ventricles. CONCLUSION: Transfusion produced little immediate effect on cardiac function, but did change the EF to an extent that aided cardiac function in chronic anemia patients. The pretransfusion EF itself, but not the degree of anemia or volume of red cells transfused, affected the posttransfusion change in EF.  相似文献   
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