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This study has development of a 6-DoF force/torque sensor for the robot arm, including the design, analysis, implementation and test verification of the sensing structure, digital multi-axis read circuit and nonlinear calibration module. We has build-up a multi-axis force/torque platform to test the 6-DoF force/torque sensor which we developed. The test results show that the force/torque range of the 6-DoF force/torque sensor can reach Fx/Fy/Fz=±980N/±980N/±980N and Tx/Ty/Tz=±156Nm/±156Nm/±156Nm respectively, while the maximum nonlinearity is 0.67%, the maximum hysteresis is 0.48%, and the maximum Crosstalk is 1.08. %.

While the role of microalloying elements on precipitation strengthening in ferrite matrix during austenite/ferrite transformation is quite clear, some uncertainty still exists concerning the variability of the microhardness distribution of ferrite grains in the isothermal holding condition. The objective of the present study was to clarify the intrinsic characteristics of carbide precipitation morphology in the ferrite matrix under different processing temperatures and times and to correlate it with austenite decomposition kinetics to elucidate why a large microhardness distribution occurs at low isothermal holding temperature. Better understanding of carbide precipitation behavior can help researchers to determine the root cause of variation in microhardness distribution, which would allow metallurgists to produce high quality steels. Measurement with a Vickers hardness indenter revealed that, in specimens isothermally held at 625 °C, the range of Vickers hardness distribution was 240–420 after 5 min of isothermal holding, and 270–340 after 60 min. For specimens isothermally held at 725 °C, the range of Vickers hardness distribution was 200–330 for 5 min of isothermal holding, and 200–250 for 60 min. Therefore, the average microhardness decreased with the isothermal holding temperature and time, and a larger range of distribution occurred with short isothermal holding times. Transmission electron microscopy (TEM) images showed that interface precipitation and random precipitation can occur within the same ferrite grain. The reason is that the austenite decomposition rate varies with transformation temperature and time. An excessively fast austenite/ferrite interface movement velocity, which usually happens in small ferrite grains, would cause these ferrite grains with microalloying elements to exceed their solubility. Furthermore, these microalloying elements will be precipitated randomly after isothermal holding at longer times. Consequently, a large microhardness distribution can usually be detected in specimens with tiny ferrites because some ferrite grains are in a fresh state, without carbides, due to high austenite/ferrite interface movement velocities. Furthermore, one important technological limit that should be kept in mind is the difficulty of developing only one type of precipitation morphology (i.e., interface precipitation or random precipitation) within every ferrite grain.

Heat-killed lactic acid bacteria (LAB) has advantages over live LAB in that it has a long shelf‐life and is therefore easy to store and transport. From four LAB strains selected by immunomodulatory activity and adherent properties, we prepared the heat-killed multispecies combination of LAB (MLAB) and the cell walls from MLAB under two conditions (100 °C for 30 min and 121 °C for 15 min). Different effects on the adherent properties of these four LAB strains were observed, depending on the heating conditions. With mouse macrophage cells, the two heat-killed MLABs (HMLABs) showed significantly higher induction activities on the production of interleukin 12 (IL-12) than their individual strains did. Heat-killed MLABs and cell‐wall preparations were able to reduce the Salmonella invasion of Caco-2 and mouse macrophage cells. Feeding mice with HMLAB could inhibit the Salmonella invasion of mice significantly. For these mice, the expression level of pro-inflammatory cytokines, such as TNF-α and IL-6, in mouse serum was reduced while that of the anti-inflammatory cytokine, i.e. IL-10, was enhanced. The HMLABs developed in this study showed higher protective effect against Salmonella invasion either of Caco-2 cells or of mice, relative to the heat-killed lactobacilli, which consisted of Lactobacillus acidophilus strains selected at random. In conclusion, the HMLABs were potentially useful for the protection of mice against Salmonella infection and the induced inflammation.

An innovative design for capacitive wide bandwidth vibration sensor is proposed and verified by experiments in this work. Three-dimensional and high-g vibration motions can be individually detected by the proposed vibration sensor such that the other-axis effect can be reduced and the sensitivity can be enhanced. The shock absorb mechanisms, i.e., fixed-fixed beam stopper and cantilever beam stopper, are employed against the external shock acceleration so that the damage and stiction can be prevented. In addition, the readout circuit calibrated the gain and offset of the output signal which can improve the signal to noise ratio. By a series of experiments, the width and height of fabricated element are 2.45mm and 2.55mm, respectively. The bandwidths are about 15kHz/15kHz/ 10kHz with respect to X-/Y-/Z-axis, respectively. The element sensitivities of the sensor are about 0.113fF/g, 0.113fF/g and 0.095fF/g, respectively. Furthermore, the 10kG shock acceleration can be successfully absorbed by the proposed shock absorb mechanisms.

Food products, such as milk and meat products including cheese, milk powder, fermented milk, sausage, etc. are susceptible to the contamination by pathogenic and deteriorative bacteria. These bacteria include Listeria monocytogens, Staphylococcus aureus, Enterobacter sakazakii, Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Streptococcus agalactiae and Pseudomonas fluorescens, etc. Traditional methods for the detection of these microorganisms are laborious and time consuming. Therefore, rapid and accurate diagnostic methods are needed. In this study, we designed the DNA probes and PCR primers for the detection of aforementioned microorganisms. By using two sets of multiplex PCR, followed by a chromogenic macroarray system, these organisms in milk or other food products could be simultaneously detected. When the system was used for the inspection of milk or meat homogenate containing 10(0) target cells per milliliter or gram of the sample, all these bacterial species could be identified after an 8h pre-enrichment step. The system consisting of a multiplex PCR step followed by macroarray allowed us to detect multiple target bacterial species simultaneously without the use of agarose gel electrophoresis. Compared to the commonly used multiplex PCR method, this approach has the additional advantage of detecting more bacterial strains because some bacterial strains generate PCR products with the same molecular sizes which can be differentiated by macroarray but not by electrophoresis.

Streptococcus agalactiae, Streptococcus uberis, and Streptococcus bovis are three of the major pathogens which cause mastitis in dairy herds. Since conventional methods for the detection of these mastitis pathogens are laborious and time-consuming, rapid methods are needed. With an attempt to know if heat shock protein (HSP) genes other than HSP60 gene, could be used for PCR primer designing, in this study, we tried to design PCR primers based on the heat shock protein genes hsp70, hsp40, and hsp10 for the specific detection of S. agalactiae, S. uberis, and S. bovis, respectively. Using these primers, all the randomly selected target strains could be specifically detected. Bacterial species other than the target organisms, including strains of other Streptococcus spp., and strains of non-Streptococcus spp., would not generate any false positive results. As these PCR primers were used for direct detection of mastitis pathogens, the detection limit was N (N=1-9) x 10(3)CFU/ml of cell dilutions. If a 10h pre-enrichment step was performed, the detection limit was N x 10(0)CFU/ml. Thus, these primers could be used for the specific and sensitive detection of bovine mastitis bacteria.

The purpose of this study was to characterize differentially expressed transcripts associated with varying rates of egg production in Taiwan country chickens. Ovarian follicles were isolated from two strains of chicken which showed low (B) or high (L2) rates of egg production, then processed for RNA extraction and cDNA library construction. Three thousand and eight forty clones were randomly selected from the cDNA library and amplified by PCR, then used in microarray analysis. Differentially expressed transcripts (P0.05, log(2)or = 1.75) were sequenced, and aligned using GenBank. This analysis revealed 20 non-redundant sequences which corresponded to known transcripts. Eight transcripts were expressed at a higher level in ovarian tissue prepared from chicken strain B, and 12 transcripts were expressed at a higher level in L2 birds. These differential patterns of expression were confirmed by semi-quantitative RT-PCR. We show that transcripts of cyclin B2 (cycB2), ferritin heavy polypeptide 1 (FTH1), Gag-Pol polyprotein, thymosin beta4 (TB4) and elongation factor 1 alpha1 (EEF1A1) were enriched in B strain ovarian follicles. In contrast, thioredoxin (TXN), acetyl-CoA dehydrogenase long chain (ACADL), inhibitor of growth family member 4 (ING4) and annexin II (ANXA2) were expressed in at higher levels in the L2 strain. We suggest that our approach may lead to the isolation of effective molecular markers that can be used in selection programs in Taiwan country chickens.

We propose and solve an optimal robust performance problem (ORPP), attempting minimal cost of feedback (i.e. sensor noise and control effort) in achieving the prescribed performance tolerance, and thereby minimizing the conservatism involved in a robust performance design. To solve the ORPP, a conservative solution to the robust performance problem (RPP) is obtained as an initial design using the µ-synthesis, then the Q-parameterization is applied to arrive at a suboptimal solution to the ORPP. The present design methodology is applied to an ill-conditioned plant for comparison with existing methods.