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31.
Importance-performance analysis (IPA) is a decision-support tool used in prioritizing quality improvements of products/services. Recently, back-propagation neural network (BPNN)-based approaches have been proposed to deal with the problem of asymmetric effects in customer satisfaction formation. Though reliability of IPA is increased by the integration of BPNN, shortcomings of the analytical framework remain that (a) it does not provide insight into forms and degrees of these asymmetric effects, (b) it does not account for differences between the relevance and determinance of quality attributes, and (c) it neglects the competitor dimension in attribute-prioritization. Since all these issues have important managerial implications, the authors of this study propose an extended BPNN-based IPA that uses a multidimensional operationalization of attribute-importance, and that considers competitive performance levels. Using data from an airline satisfaction survey, an empirical test reveals that the proposed approach significantly outperforms conventional BPNN-based IPA. In particular, conventional BPNN-IPA would mislead managerial action with regard to 3 out of 8 quality components (37.5%).  相似文献   
32.
Mitochondrial DNA (mtDNA) fragmentation was assessed in acidified foods. Using quantitative polymerase chain reaction, Ct values measured from fresh, fermented, pasteurized, and stored cucumber mtDNA were determined to be significantly different (P > 0.05) based on processing and shelf‐life. This indicated that the combination of lower temperature thermal processes (hot‐fill at 75 °C for 15 min) and acidified conditions (pH = 3.8) was sufficient to cause mtDNA fragmentation. In studies modeling high acid juices, pasteurization (96 °C, 0 to 24 min) of tomato serum produced Ct values which had high correlation to time‐temperature treatment. Primers producing longer amplicons (approximately 1 kb) targeting the same mitochondrial gene gave greater sensitivity in correlating time‐temperature treatments to Ct values. Lab‐scale pasteurization studies using Ct values derived from the longer amplicon differentiated between heat treatments of tomato serum (95 °C for <2 min). MtDNA fragmentation was shown to be a potential new tool to characterize low temperature (<100 °C) high acid processes (pH < 4.6), nonthermal processes such as vegetable fermentation and holding times of acidified, plant‐derived products.  相似文献   
33.
The organization and circuit design of a 1.0 GHz integer processor built in 0.25 μm CMOS technology are presented, a microarchitecture emphasizing parallel computation with a single late select per cycle, structured control logic implemented by read-only-memories and programmable logic arrays, and a delayed reset dynamic circuit style enabling complex functions to be implemented in a few levels of logic are among the key design choices described. A means for at-speed scan testing of this high-frequency processor by a low-speed tester is also presented  相似文献   
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Genetic analyses and association mapping were performed on a winter wheat core collection of 96 accessions sampled from a variety of geographic origins. Twenty-four agronomic traits were evaluated over 3 years under fully irrigated, rainfed and drought treatments. Grain yield was the most sensitive trait to water deficit and was highly correlated with above-ground biomass per plant and number of kernels per m(2). The germplasm was structured into four subpopulations. The association of 46 SSR loci distributed throughout the wheat genome with yield and agronomic traits was analyzed using a general linear model, where subpopulation information was used to control false-positive or spurious marker-trait associations (MTAs). A total of 26, 21 and 29 significant (P < 0.001) MTAs were identified in irrigated, rainfed and drought treatments, respectively. The marker effects ranged from 14.0 to 50.8%. Combined across all treatments, 34 significant (P < 0.001) MTAs were identified with nine markers, and R(2) ranged from 14.5 to 50.2%. Marker psp3200 (6DS) and particularly gwm484 (2DS) were associated with many significant MTAs in each treatment and explained the greatest proportion of phenotypic variation. Although we were not able to recognize any marker related to grain yield under drought stress, a number of MTAs associated with developmental and agronomic traits highly correlated with grain yield under drought were identified.  相似文献   
36.
Continuous microwave processing to produce shelf-stable acidified vegetables with moderate to high salt contents poses challenges in pasteurization due to reduced microwave penetration depths and non-uniform heating. Cups of sweetpotato, red bell pepper, and broccoli acidified to pH 3.8 with citric acid solution containing 0-1% NaCl were placed on a conveyor belt and passed through a microwave tunnel operating at 915 MHz and 4 kW with a 4 min residence time. The time-temperature profiles of vegetable pieces at 5 locations in the package were measured using fiber optic temperature sensors. Addition of 1% NaCl to the cover solution lowered microwave penetration into vegetable pieces and decreased the mean temperature in cups of acidified vegetables from 84 to 73 °C. Soaking blanched vegetables for 24 h in a solution with NaCl and citric acid prior to processing improved microwave heating. Heating was non-uniform in all packages with a cold spot of approximately 60 °C at a point in the container farthest from the incident microwaves. More uniform heating was achieved by implementation of a two-stage rotation apparatus to rotate vegetable cups 180° during processing. Rotating the cups resulted in more uniform heating and a temperature of 77 °C at the cold spot. This is above the industrial standard of 74 °C for in-pack pasteurization of acidified vegetables. The effective treatment involved blanching, soaking for 24 h in a NaCl and citric acid solution, and 180° rotation. This work has contributed to a better understanding of the influence of salt addition and distribution during dielectric heating of acidified vegetables using a 915 MHz continuous microwave system.  相似文献   
37.
Antisense peptide technology (APT) is based on a useful heuristic algorithm for rational peptide design. It was deduced from empirical observations that peptides consisting of complementary (sense and antisense) amino acids interact with higher probability and affinity than the randomly selected ones. This phenomenon is closely related to the structure of the standard genetic code table, and at the same time, is unrelated to the direction of its codon sequence translation. The concept of complementary peptide interaction is discussed, and its possible applications to diagnostic tests and bioengineering research are summarized. Problems and difficulties that may arise using APT are discussed, and possible solutions are proposed. The methodology was tested on the example of SARS-CoV-2. It is shown that the CABS-dock server accurately predicts the binding of antisense peptides to the SARS-CoV-2 receptor binding domain without requiring predefinition of the binding site. It is concluded that the benefits of APT outweigh the costs of random peptide screening and could lead to considerable savings in time and resources, especially if combined with other computational and immunochemical methods.  相似文献   
38.
We present a method to optimize the epitaxial layer structure of an InGaAs/InP uni-traveling-carrier photo-diode (UTC-PD) for continuous THz-wave generation. The design approach used is general in that it can be applied for any target frequency while this study focuses on 340 GHz. The photodiode epitaxy is modeled and optimized using a TCAD software implementing the hydrodynamic semiconductor equations. This physical device model was found to be in good agreement with reported experimental results. It is shown that the UTC-PD can generate ~1 mW at 340 GHz by choosing the optimum absorption layer and collection layer thicknesses.  相似文献   
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This paper presents dynamical properties of an unmanned aerial vehicle (UAV), called spincopter. The vehicle structure is based on two wings that are forced in rotation (spinning) by propulsion system formed of two propellers. Based on devised dynamical model, that reveals inherent stability of the vehicle, composition of control algorithms for vertical and horizontal movement is proposed. Due to the specific configuration of the propulsion system, movement in horizontal direction is produced by pulsations in rotational speed of propulsion motors. An analysis of influence that such a configuration has on the vehicle dynamics is given. Finally, design recommendations for rotational wings are elaborated, based on extensive simulations of spincopter by using X-Plane® software package.  相似文献   
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