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91.
The main topics discussed in this paper include sensor integration, data extraction, data processing, monitoring the cutting tool, safety of the tool machinery, and quality of the components in processing. The detection method used in this paper is to extract the workload of a spindle motor from a CNC controller, and then transmit the data via a I/O card for further processing. The computer is connected to the CNC by DNC and is able to detect abnormal conditions and transmit, through DNC, to CNC the NC program to stop the machine or to replace the cutting tool. The systematic architectural instrument develops tools with object-oriented professional software and establishes software structure using a visual component library. The software component structure is made easy for maintaining and extending programs and for the operating system with its graphics user interface.  相似文献   
92.
Coxsackievirus A16 (CA16) is one of the major causative agents of hand, foot, and mouth disease (HFMD). Children aged <5 years are the most affected by CA16 HFMD globally. Although clinical symptoms of CA16 infections are usually mild, severe complications, such as aseptic meningitis or even death, have been recorded. Currently, no vaccine or antiviral therapy for CA16 infection exists. Single-chain variable fragment (scFv) antibodies significantly inhibit viral infection and could be a potential treatment for controlling the infection. In this study, scFv phage display libraries were constructed from splenocytes of a laying hen immunized with CA16-infected lysate. The pComb3X vector containing the scFv genes was introduced into ER2738 Escherichia coli and rescued by helper phages to express scFv molecules. After screening with five cycles of bio-panning, an effective scFv antibody showing favorable binding activity to proteins in CA16-infected lysate on ELISA plates was selected. Importantly, the selected scFv clone showed a neutralizing capability against the CA16 virus and cross-reacted with viral proteins in EV71-infected lysate. Intriguingly, polyclonal IgY antibody not only showed binding specificity against proteins in CA16-infected lysate but also showed significant neutralization activities. Nevertheless, IgY-binding protein did not cross-react with proteins in EV71-infected lysate. These results suggest that the IgY- and scFv-binding protein antibodies provide protection against CA16 viral infection in in vitro assays and may be potential candidates for treating CA16 infection in vulnerable young children.  相似文献   
93.
Cerium (Ce)-substituted diopsides (CaMgSi2O6) with enhanced mechanical strength and bioactivity were fabricated by precipitation method, followed by annealing at 1000 °C for 4 h. The mineralogical, morphological, in vitro biomineralization, degradation, and mechanical properties were investigated in order to assess the factors and mechanisms affecting the resultant properties. The X-ray diffractometer results showed that the onset of substitutional solid solubility in 0.25 mol Ce would result in new phase formation (cerium dioxide [CeO2], and magnesium silicate [MgSiO3]) further causing lattice instability. With increasing Ce dopant levels to 1.00 mol, the initial CaMgSi2O6 phase was completely replaced by new phases. The field-emission scanning electron microscopy results indicated that the 0.25 mol Ce had the best biomineralization performance in vitro, while less hydroxyapatite precipitates were found with further increasing Ce dopant levels, suggesting the new phases led to the hindrance of precipitates. The weight loss values indicated that the high dissolution rate of ions in the matrix was observed in the pure sample, while the high readsorption rate of ions in the simulated body fluid (SBF) occurred with increasing Ce dopant levels. The pH value and the inductively coupled plasma-mass spectrometer results suggested that the release of Ca and Mg ions controlled the pH value. The mechanical strength of matrices before SBF immersion was related to the phase transformation, the elastic modulus of CeO2 and CaMgSi2O6, and the release of Mg ions, while the mechanical strength of matrices after SBF immersion was dominated by the structure of matrices.  相似文献   
94.
The heat transfer and flow characteristics of a photoelectrochemical (PEC) hydrogen generation reactor are investigated numerically. Four different reactor designs are considered in this study. The solar irradiation is separated into short and long wavelength parts depending on the energy band gap of the photoelectrode used. While short wavelength part is used to generate electron and hole pairs, the long wavelength part is used to heat the system. Because the energy required for splitting water decreases as temperature is increased, heating the reactor by using the long wave energy increases the system efficiency. Thus, how the long wavelength energy is absorbed by the reactor is very important.The results show that more long wavelength energy kept inside the reactor can increase the solar-to-hydrogen efficiency, ηSH. For Fe2O3 photoelectrode, careful reactor design can increase ηSH by 11.0%. For design D under 4000 W/m2 irradiation and a quantum efficiency of 30%, ηSH is found to be 14.1% and the hydrogen volume production rate is 166 L/m2 h for Fe2O3. Effects of several parameters on the PEC hydrogen reactor are also discussed.  相似文献   
95.
A comprehensive study has been made to explore the role of organic acids on electrocatalytic performances of platinum (Pt) nanoparticles supported on carbon porous materials (CPMs) in proton exchange membrane fuel cells (PEMFCs). In particular, the effects of carboxylic acids (R–COOH), viz. formic acid, acetic acid, propionic acid, and butyric acid on catalytic activity, stability, and durability of anodic Pt/CPM electrocatalyst in direct methanol fuel cells (DMFCs) were investigated. In the presence of doped carboxylic acids, the electrooxidative activity of Pt/CPM follows the trend: HCOOH < CH3COOH < C2H5COOH < C3H7COOH, revealing a consistent increase in the severity of catalyst deactivation with the number of carbons on the alkyl chain of the dopant. The Pt/CPM was found to exhibit electrocatalytic performances and tolerance for poisoning than a commercial Pt/XC-72 catalyst with a similar Pt loading (20 wt%). Moreover, a notable increase in mass activity up to ca. 150% over the spent Pt/CPM catalyst was observed up on removing the organic acid in the feed stream, indicating that catalyst poisoning by deactivation may be revived, even to its “intrinsic” activity.  相似文献   
96.
In this study, the discrete ordinates method (DOM) model is employed to estimate the effect of thermal radiation from multiple heat sources in a natural-convection flow field. It is found that the flow field around the chips can be altered by natural convection as induced by radiative heat transfer. The influence of thermal radiation is higher than 65% when the chipboard is in a vertical orientation. Furthermore, even if the chip surface temperature is only 317 K, the influence of radiative heat transfer is still up to 18%. Therefore, radiative heat transfer cannot be ignored for electronic component computational fluid dynamics simulation under natural convection.  相似文献   
97.
Tseng TF  Liu DC  Chen MT 《Meat science》2000,55(4):30-431
The purpose of this study was to examine the effect of different concentrations of crude pig plasma transglutaminase (TGase) at 0, 0.05, 0.1, 0.2, 0.4 and 1.0% on the quality of low-salt chicken meat-balls. Yield, color, gel strength, microstructure and sensory evaluation were measured. The results showed that both the yield and gel strength of the meat-balls increased as TGase supplement increased (P<0.05) without any obvious effect on color. Scanning electron microscopy (SEM) indicated firmer and more regular gel structures with increasing TGase addition. Texture, juiciness and overall acceptability as judged by sensory evaluation were not statistically affected until the level of TGase reached 1.0% (P<0.05).  相似文献   
98.
We provide a more general and, in our eyes, simpler variant of Prabhakaran, Rosen and Sahai’s (FOCS ’02, pp. 366–375, 2002) analysis of the concurrent zero-knowledge simulation technique of Kilian and Petrank (STOC ’01, pp. 560–569, 2001).  相似文献   
99.
The Orphan Problem in ZigBee Wireless Networks   总被引:2,自引:0,他引:2  
ZigBee is a communication standard which is considered to be suitable for wireless sensor networks. In ZigBee, a device (with a permanent 64-bit MAC address) is said to join a network if it can successfully obtain a 16-bit network address from a parent device. Parent devices calculate addresses for their child devices by a distributed address assignment scheme. This assignment is easy to implement, but it restricts the number of children of a device and the depth of the network. We observe that the ZigBee address assignment policy is too conservative, thus usually making the utilization of the address pool poor. Those devices that cannot receive network addresses will be isolated from the network and become orphan nodes. In this paper, we show that the orphan problem can be divided into two subproblems: the bounded-degree-and-depth tree formation (BDDTF) problem and the end-device maximum matching (EDMM) problem. We then propose algorithms to relieve the orphan problem. Our simulation results show that the proposed schemes can effectively reduce the number of orphan devices compared to the ZigBee strategy.  相似文献   
100.
This paper presents a self-testing and calibration technique for the embedded successive approximation register (SAR) analog-to-digital converter (ADC) in system-on-chip (SoC) designs. We first proposed a low cost design-for-test (DfT) technique that estimates the SAR ADC performance before and after calibration by characterizing its digital-to-analog converter (DAC) capacitor weights (bit weights). Utilizing major carrier transition (MCT) testing, the required analog measurement range is only about 1 LSB; this significantly reduces test circuitry complexity. Then, we develop a fully-digital calibration technique that utilizes the extracted bit weights to correct the non-ideal I/O behavior induced by capacitor mismatch. Simulation results show that (1) the proposed testing technique achieves very high test accuracy even in the presence of large noise, and (2) the proposed calibration technique effectively improves both static and dynamic performances of the SAR ADC.  相似文献   
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