Modeling experts' consensual judgments for new product entry timing

This paper presents a modeling technique that extracts judgments and decisions from experts to derive a consensual model for decision support. The proposed approach is applied to build a decision support system for the new product entry timing decision. Experience learned from the proposed methodology suggests that it is possible to: 1) capture consensual knowledge from a group of experts, 2) model simultaneous relationships among interacting factors, and 3) offer a robust decision support tool     

Existence of partial discharges in low-voltage induction machinessupplied by PWM drives

When standard low voltage induction motors are supplied by pulse-width modulated (PWM) adjustable speed drives, some of the traditional sinusoidal system concepts cannot be applied. This paper reports the results of an investigation of the effect of PWM drives on the insulation of the stator winding. The characteristics of the employed dielectric material and the magnitude of the applied voltages led to the hypothesis of the possible existence of partial discharges within the insulation. Practical experiments were carried out and high frequency signals which could be associated with such a phenomenon were observed. These measurements also showed that the interturn insulation undergoes some high electrical stresses and that the nominal rotation speed (50 Hz) appears to be a point of high disturbance in the working of the motor. Further work is required, since most of the points identified here need to be understood fully     

Enzymatic characterization of immunopurified prohormone convertase 2: potent inhibition by a 7B2 peptide fragment

Prohormone convertase (PCs) are thought to mediate the controlled proteolysis of prohormones and neuropeptide precursors. While recombinant PC1 and furin are currently available, thus far it has not been possible to produce recombinant PC2. We have used conditioned medium obtained from the mouse insulinoma cell line beta TC3 to generate a working preparation of enzymatically active PC2 through immunopurification. Immunopurified PC2 cleaved the fluorogenic substrate Cbz-Arg-Ser-Lys-Arg-AMC in a time- and calcium-dependent manner. It was half-maximally stimulated at 75 microM Ca2+, had an optimum pH of 5, and exhibited PCMS and EDTA sensitivity similar to that reported for furin and PC1. The tight-binding inhibitor 27 kDa 7B2 was used to calculate the Kd for this inhibitor and the active enzyme concentration. The Kd was 7.3 +/- 1.7 nM, and the turnover rate of PC2 was 5.2 molecules substrate per enzyme molecule per minute. The specific activity was 4.9 nmol/micrograms/h (assuming a molecular mass for PC2 of 64 kDa). The enzyme preparation was able to cleave recombinant proenkephalin at at least four of the expected paired basic sites in the absence, but not in the presence, of 27 kDa 7B2. Since 21 kDa 7B2 is functionally inactive as a proteinase inhibitor, we examined the inhibitory activity of the carboxy-terminal portion of 27 kDa 7B2 (7B2 CT-peptide). Synthetic peptides were used to demonstrate that the 7B2 CT-peptide (a) represents a potent inhibitor of PC2 (Ki = 57 nM), (b) can block the conversion of proPC2 to PC2, and (c) can block the PC2-mediated conversion of proenkephalin to smaller peptide fragments.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of carbonaceous materials on electrochemical properties of nano-sized Fe2O3-loaded carbon as a lithium battery negative electrode

Nano-sized Fe₂O₃-loaded carbon material was prepared by loading Fe₂O₃ on carbon using various carbonaceous materials. Carbonaceous materials strongly affected the electrochemical behavior of nano-sized Fe₂O₃-loaded carbon. Among the carbons used, nano-carbons such as acetylene black (AB), tubular carbon nanofibers (CNF), and platelet CNF provided larger capacities than other carbons. This may be due to the greater surface area of nano-carbon, which gives a greater distribution of nano-sized Fe₂O₃ particles than other carbons and delivers a greater capacity than other carbons. Investigation of the first-cycle materials by X-ray photoelectron spectroscopy (XPS) revealed that Fe₂O₃ was reduced to Fe metal in the charge process (reduction of Fe₂O₃), and, conversely, Fe metal was not completely oxidized to Fe₂O₃ during discharge (oxidation of Fe). This result may be due to the covering of non-conductive Li₂O formed during charging.     

Basic tuning of hydrogen powered car and artificial intelligent prediction of hydrogen engine characteristics

Many studies of renewable energy have shown hydrogen is one of the major green energy in the future. This has lead to the development of many automotive application of using hydrogen as a fuel especially in internal combustion engine. Nonetheless, there has been a slow growth and less knowledge details in building up the prototype and control methodology of the hydrogen internal combustion engine [1]. In this paper, The Toyota Corolla 4 cylinder, 1.8l engine running on petrol was systematically modified in such a way that it could be operated on either gasoline or hydrogen at the choice of the driver. Within the scope of this project, several ancillary instruments such as a new inlet manifold, hydrogen fuel injection, storage system and leak detection safety system were implemented. Attention is directed towards special characteristics related to the basic tuning of hydrogen engine such as: air to fuel ratio operating conditions, ignition timing and injection timing in terms of different engine speed and throttle position. Based on the experimental data, a suite of neural network models were tested to accurately predict the effect of different engine operating conditions (speed and throttle position) on the hydrogen powered car engine characteristics. Predictions were found to be ±3% to the experimental values for all of case studies. This work provided better understanding of the effect of hydrogen engine characteristic parameters on different engine operating conditions.     

Thermophilic bio-energy process study on hydrogen fermentation with vegetable kitchen waste

An intermittent-continuous stirred tank reactor (I-CSTR) was evaluated for thermophilic anaerobic hydrogen fermentation with vegetable kitchen waste (VKW). The seeding sludge was enriched from kitchen waste compost. Because of different seasonal dietary habits, the quality of vegetable kitchen waste was unstable, and all variations of composition were in the range from 20 to 40%. The I-CSTR process was conducted under different volumetric loading rates (VLR) with different VKW-diluted concentrations. The hydrogen production rate and yield in Run 2 (VLR as 28 g-COD L⁻¹ day⁻¹) were 1.0 L-H₂ L⁻¹ day⁻¹ and 1.7 mmol-H₂ g-COD⁻¹, which were higher than those in Run1 (VLR as 19 g-COD/L-day). The hydrolysis efficiency of organic solids (VSS) was about 45% in Run 1 better than the 32% in Run 2. The carbohydrate component of VKW was clearly degraded with the accumulation of butyrate, while the organic nitrogen component was converted to ammonia. The vegetable cellulose was degraded from 3.2 g L⁻¹ and 3.6–1.8 and 3.2 g L⁻¹ in Runs 1 and 2, respectively. In addition, the high concentration of lactate from the acidified VKW could be degraded completely both in Runs 1 and 2. According to the results of the time series profile in day 59, oil and grease were not degraded significantly. The removal of oil and grease was superficially caused by stacking on the wall, pipe, and propeller of the reactor, or by floating on the liquid surface. The 16S rDNA cloning library and sequence were applied for analyzing microbial communities. The dominant OTU was closely affiliated to Thermoanaerobacterium thermosaccharolyticum, which is considered as the predominant hydrogen-producing bacteria. The OTUs closely related to Moorella thermoacetica and Clostridiaceae bacterium FH052 were considered as acetogenic bacterium and hydrogen-producing bacteria in the I-CSTR system.