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31.
The current work presents a pilot scale study in which the effect of in pack thermal preservation processes in a retort system on particular carrot quality aspects, more specifically nutritional and textural characteristics, was investigated. Pasteurization as well as sterilization processes with different intensities were included. The carrot hardness, analyzed by a compression test, and the β-carotene bio-accessibility, analyzed by an in vitro digestion method, were the main quality markers. As a main conclusion, it can be stated that the results of this pilot scale study are a good validation of results obtained during previous laboratory scale experiments on carrot nutritional and textural characteristics. The processes applied in this study only resulted in limited conversion of all-trans-β-carotene to its cis-isomers. Furthermore, it was shown that intense thermal processing is required to observe a significant increase in the β-carotene bio-accessibility. However, this was accompanied with a clear degradation of the hardness. When thermal processing was preceded by low temperature blanching, a technique to improve texture retention of thermally processed plant-based foods, a lower β-carotene bio-accessibility was observed. Both observations clearly illustrated the inverse correlation between textural and nutritional characteristics of (processed) carrots. Statistical analyses confirmed the trends observed. For process design, the choice of the process intensity was identified to be crucial: the required product safety needs to be achieved, while still reaching an acceptable structural and nutritional quality. Exploring strategies to enhance the β-carotene bio-accessibility while ensuring an acceptable carrot texture can therefore be useful.  相似文献   
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33.
In this paper, we investigate band-structure effects on the transport properties of ultrascaled silicon nanowire FETs operating under quantum-ballistic conditions. More specifically, we expand the dispersion relationship epsiv(kappa) in a power series up to the third order in kappa2 and generate the corresponding higher order operator to be used within the single-electron Hamiltonian for the solution of the Schrodinger equation. We work out a hierarchy of nonparabolic models accounting for the following: 1) the shift of the subband edges and the change in the transport effective masses; 2) the higher order Hamiltonian operator; and 3) the splitting of the fourfold unprimed subbands in nanometer-size FETs. We then compute the device turn-on characteristics, the threshold shift versus diameter, and the subthreshold slope (SS) versus gate length. By compensating for the different threshold voltages, i.e., by reducing the turn- on characteristics to the same leakage current at zero gate bias, it turns out that the current discrepancies between the most general model and the bulk-parabolic model are contained within 20%. Finally, it turns out that the nonparabolic band structure gives an improved SS at the lowest gate lengths due to a reduced source-drain tunneling, reaching up to 30% enhancement.  相似文献   
34.
The authors investigated the differences between 8-year-olds (n = 80) and adults (n = 80) in recognition of felt versus faked enjoyment smiles by using a newly developed picture set that is based on the Facial Action Coding System. The authors tested the effect of different facial action units (AUs) on judgments of smile authenticity. Multiple regression showed that children base their judgment on AU intensity of both mouth and eyes, with relatively little distinction between the Duchenne marker (AU6 or "cheek raiser") and a different voluntary muscle that has a similar effect on eye aperture (AU7 or "lid tightener"). Adults discriminate well between AU6 and AU7 and seem to use eye-mouth discrepancy as a major cue of authenticity. Bared-teeth smiles (involving AU25) are particularly salient to both groups. The authors propose and discuss an initial developmental model of the smile recognition process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
In this article, we present a detailed performance evaluation of a hybrid optical switching (HOS) architecture called Overspill Routing in Optical Networks (ORION). The ORION architecture combines (optical) wavelength and (electronic) packet switching, so as to obtain the individual advantages of both switching paradigms. In particular, ORION exploits the possible idle periods of established lightpaths to transmit packets destined to the next common node, or even directly to their common end-destination. Depending on whether all lightpaths are allowed to simultaneously carry and terminate overspill traffic or overspill is restricted to a sub-set of wavelengths, the architecture limits itself to constrained or un-constrained ORION. To evaluate both cases, we developed an extensive network simulator where the basic features of the ORION architecture were modeled, including suitable edge/core node switches and load-varying sources to simulate overloading traffic conditions. Further, we have assessed various aspects of the ORION architecture including two basic routing/forwarding policies and various buffering schemes. The complete network study shows that ORION can absorb temporal traffic overloads, as intended, provided sufficient buffering is present. We also demonstrate that the restriction of simultaneous packet insertions/extractions, to reduce the necessary interfaces, do not deteriorate performance and thus the use of traffic concentrators assure ORION’s economic viability.  相似文献   
36.
We examined the different personality dimensions between depression and anxiety with Cloninger's seven-factor model of temperament and character. The Temperament and Character Inventory (TCI), which measures four temperament and three character dimensions of Cloninger's personality theory (125-item short version), the Self-rating Depression Scale (SDS), and the State-Trait Anxiety Inventory (STAI) were administered to 223 Japanese students. With hierarchical regression analysis, the SDS score was predicted by scores of Harm-Avoidance, Self-Directedness, and Self-Transcendence, even after controlling for the STAI score. The STAI score was predicted by scores of Self-Directedness and Cooperativeness, even after controlling for the SDS score. More importance should be attached to these dimensions of character because they might contribute to both depression and anxiety.  相似文献   
37.
Colle HA  Reid GB 《Human factors》2003,45(3):424-435
Understanding how spatial knowledge is acquired is important for spatial navigation and for improving the design of 3-D perspective interfaces. Configural spatial knowledge of object locations inside rooms is learned rapidly and easily (Colle & Reid, 1998), possibly because rooms afford local viewing in which objects are directly viewed or, alternatively, because of their structural features. The local viewing hypothesis predicts that the layout of objects outside of rooms also should be rapidly acquired when walls are removed and rooms are sufficiently close that participants can directly view and identify objects. It was evaluated using pointing and sketch map measures of configural knowledge with and without walls by varying distance, lighting levels, and observation instructions. Although within-room spatial knowledge was uniformly good, local viewing was not sufficient for improving spatial knowledge of objects in different rooms. Implications for navigation and 3-D interface design are discussed. Actual or potential applications of this research include the design of user interfaces, especially interfaces with 3-D displays.  相似文献   
38.
Results of oxidation experiments on high-burn-up UO2 are presented where fission-product vaporisation and release rates have been measured by on-line mass spectrometry as a function of time/temperature during thermal annealing treatments in a Knudsen cell under controlled oxygen atmosphere. Fractional release curves of fission gas and other less volatile fission products in the temperature range 800-2000 K were obtained from BWR fuel samples of 65 GWd t−1 burn-up and oxidized to U3O8 at low temperature. The diffusion enthalpy of gaseous fission products and helium in different structures of U3O8 was determined.  相似文献   
39.
The addition of a mobile platform to a 6-DOF arm raises the question of the exploitation of redundancy with respect to needs. The application field concerns assistive robotics for object manipulation tasks. Works deal with the utilisability of a mobile arm, which is a complex system, by a disabled person with reduced motor and perception abilities. In this paper, we present the influence of mobility on manipulability measure. Manipulability is a well-established tool for motion analysis which we use as criterion in control scheme to improve the coordination of two subsystems. We propose a normalized measure to solve problems inherent to the use of different physical units and velocity limits for both components of the system, arm and mobile platform. Simulation results for a 3D positioning task are given to show the effect of nonholonomic constraint on manipulability measure.  相似文献   
40.
IP-based backbone networks are gradually moving to a network model consisting of high-speed routers that are flexibly interconnected by a mesh of light paths set up by an optical transport network that consists of wavelength division multiplexing (WDM) links and optical cross-connects. In such a model, the generalized MPLS protocol suite could provide the IP centric control plane component that will be used to deliver rapid and dynamic circuit provisioning of end-to-end optical light paths between the routers. This is called an automatic switched optical (transport) network (ASON). An ASON enables reconfiguration of the logical IP topology by setting up and tearing down light paths. This allows to up- or downgrade link capacities during a router failure to the capacities needed by the new routing of the affected traffic. Such survivability against (single) IP router failures is cost-effective, as capacity to the IP layer can be provided flexibly when necessary. We present and investigate a logical topology optimization problem that minimizes the total amount or cost of the needed resources (interfaces, wavelengths, WDM line-systems, amplifiers, etc.) in both the IP and the optical layer. A novel optimization aspect in this problem is the possibility, as a result of the ASON, to reuse the physical resources (like interface cards and WDM line-systems) over the different network states (the failure-free and all the router failure scenarios). We devised a simple optimization strategy to investigate the cost of the ASON approach and compare it with other schemes that survive single router failures.  相似文献   
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