Parameter identification of simplified common‐mode equivalent circuit for inverter‐fed motor drive systems by applying computer‐aided optimization software

This paper deals with common‐mode (CM) electromagnetic interference (EMI) in an inverter‐fed motor drive system. A simplified CM equivalent circuit including π‐type equivalent circuit for the motor winding is proposed by using the waveform of the common‐mode current flowing in the ground conductor. Moreover, a parameter identification method applying the computer‐aided software modeFRONTIER is proposed to decide objectively the circuit parameters of the proposed simplified equivalent circuit. Validity and effectiveness of the proposed equivalent circuit are confirmed by comparing the measured impedance characteristics with the calculated ones. Finally, the possibility of a nonlinear phenomenon is discussed in this system. It is shown that the accuracy of simulation result can be improved by introducing the nonlinear element. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Interspecies comparison of hepatic metabolism of six newly synthesized retinoid X receptor agonistic compounds possessing a 6-[N-ethyl-N-(alkoxyisopropylphenyl)amino]nicotinic acid skeleton in rat and human liver microsomes

Objective: The hepatic metabolism of six compounds newly synthesized as retinoid X receptor agonists was characterized in rat and human liver microsomes to examine the relationship between their hepatic metabolism profiles and side chain structures, considering the interspecies difference.

Materials and methods: The compounds used have a 6-[N-ethyl-N-(3-alkoxy-4-isopropylphenyl)amino]nicotinic or 6-[N-ethyl-N-(4-alkoxy-3-isopropylphenyl)amino]nicotinic acid skeleton, in which the isopropoxy, isobutoxy or cyclopropylmethoxy group is employed for the alkoxy group. These compounds were incubated with the microsomes, and their Michaelis--Menten parameters were determined. The incubation study was also performed with various cytochrome P450 (CYP) inhibitors to examine their susceptibilities to the inhibitors. In addition, a molecular docking simulation was conducted to assess the compound’s spatial configuration with the CYP isoform when necessary.

Results: The Michaelis--Menten parameters determined are comparable between rats and humans for the compounds having 3-isobutoxy, 4-isobutoxy, 4-isopropoxy and 4-cyclopropylmethoxy groups. However, it was indicated that all compounds except that having the 3-isobutoxy group are metabolized in a different manner between rats and humans. That is, the extent of the contribution of each CYP isozyme is different between those two species. A molecular docking simulation showed that the spatial configuration of the compound to be associated with CYP2D6 markedly changes depending on whether the isobutoxy group is situated at the 3- or 4-position.

Conclusion: A slight difference in the side chain structures markedly alters the compound’s metabolic profile, which amplifies the interspecies difference regarding the profile, increasing the difficulty in characterizing the profile in humans with the structural-property relationship and interspecies extrapolation.     

Multi-modal Gesture Recognition using Integrated Model of Motion,Audio and Video

Gesture recognition is used in many practical applications such as human-robot interaction, medical rehabilitation and sign language. With increasing motion sensor development, multiple data sources ha...     

Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (peanuts)

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.     

Sensorless IPMSM position estimation based on multi SVPWM with elimination of inverter nonlinear effects

This paper presents a position‐sensorless interior permanent magnet synchronous motor (IPMSM) control system at low and zero speed based on a multi‐space‐vector pulse‐width modulation (MSVPWM) pattern with the elimination of nonlinear inverter effects. In conventional sensorless methods based on the MSVPWM pattern, the high‐frequency (HF) components of voltage and current are used to estimate the rotor position information. However, the inverter nonlinear effects, such as forward voltage drops and deadtime, distort the HF components of the voltage and current so that an error occurs in the position estimation. Therefore, an improved position estimation scheme is developed in this paper. The compensated HF components of the voltage taking account of the inverter nonlinear effects can be used to decrease the estimation error. The proposed method can be implemented without increasing any hardware cost. Experimental results confirm the effectiveness of the proposed method. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Targeted proteome analysis of microalgae under high-light conditions by optimized protein extraction of photosynthetic organisms

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Fabrication of a Gradient Nano-/Micro-structured Surface Layer on an Al–Si Casting Alloy by Means of Ultrasonic–Electropulsing Coupling Rolling Process

By using a novel surface modification technique named ultrasonic–electropulsing coupling rolling(UECR) process on an Al–Si casting alloy rod, the surface of material was smoothened significantly. Meanwhile, a strengthened layer with a gradient change in hardness was obtained in the outer surface, corresponding to a homogeneous gradient nano-/microstructure. The thickness of nanometer-thick laminated structures was at least 40 μm, which was much thicker than conventional ultrasonic rolling process. During UECR, the formation of the well-defined nanocrystalline structure was attributed to the high strain rate and simultaneous annealing process realized by ultrasonic impact and electropulsing treatment.     

Co2+-Substitution Effect in Ce-TZP/La M-type Hexaferrite Composites

A Ce-TZP/platelike La(Co(Fe_0.9Al_0.1)₁₁)O₁₉ composite was synthesized in situ while sintering from a mixture of Ce-TZP, La(Fe_0.9Al_0.1)O₃, Fe₂O₃, Al₂O₃, and CoO powders. Platelike La(Co(Fe_0.9Al_0.1)₁₁)O₁₉ crystals were grown in a dense Ce-TZP matrix after sintering at temperatures of 1200°–1350°C. The temperature range for sintering Ce-TZP/La(Fe,Al)₁₂O₁₉ composites was expanded widely by substituting Co²⁺ ions for Fe²⁺ ions in its structure. The highest value of the bending strength of the Ce-TZP/La(Co(Fe_0.9Al_0.1)₁₁)O₁₉ composites was 880 MPa, which was higher than that of the Ce-TZP/La(Fe,Al)₁₂O₁₉ composite (780 MPa) and Ce-TZP (513 MPa). The saturation magnetization of the Ce-TZP/La(Co(Fe_0.9Al_0.1)₁₁)O₁₉ composite was a constant value of 7.7 emu/g after the composite was sintered at 1200°–1350°C.     

Safety assessment of genetically engineered potatoes with designed soybean glycinin: compositional analyses of the potato tubers and digestibility of the newly expressed protein in transgenic potatoes

The compositions of transgenic potatoes with intact and modified genes for soybean glycinin were compared with those of control potatoes; non-transgenic or transgenic ones with a vector. The expression levels of glycinin proteins in the transgenic potato tubers were approximately 12–31 mg g⁻¹-total soluble protein. With reference to six major components, moisture, protein, lipid, fiber, ash and carbohydrate, there were no significant differences between transgenic and control potatoes. The levels of glycoalkaloids in transgenic potato tubers, as well as in transgenic controls, increased in comparison with those in non-transgenic ones, though the level was within the permitted limit. The modified glycinin expressed in the transgenic potato tuber was digested under the simulated gastric conditions. From these results, the transgenic potatoes with intact and modified glycinin genes are considered to be as safety utilization for food as non-transgenic potatoes. © 1999 Society of Chemical Industry