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1.
This paper presents fault-tolerant protocols for fast packet switch networks withconvergence routing. The objective is to provide fast reconfiguration and continuous host-to-host communication after a link or a node (switch) failure,Convergence routingcan be viewed as a variant ofdeflection routing,which combines, in a dynamic fashion, the on-line routing decision with the traffic load inside the network. Unlike other deflection techniques, convergence routing operates withglobal sense of directionand guarantees that packets will reach or converge to their destinations. Global sense of direction is achieved by embedding of virtual rings to obtain a linear ordering of the nodes. We consider virtual ring embeddings over (i) a single spanning tree, and (ii) over two edge-disjoint spanning trees. Thus, the fault-tolerant solution is based on spanning trees and designed for a switch-based (i.e., arbitrary topology) architecture called MetaNet. In this work, the original MetaNet's convergence routing scheme has been modified in order to facilitate the property that the packet header need not be recomputed after a failure and/or a reconfiguration. This is achieved by having, at the network interface, a translator that maps the unique destination address to a virtual address. It is argued that virtual rings embedded over two-edge disjoint spanning trees increase the fault tolerance for both node and link faults and provides continuous host-to-host communication.  相似文献   
2.
Eosinophil count in peripheral blood, nasal secretion and nasal mucosa were studied in 20 controls and 38 patients with different patterns of allergic rhinits. Secretion and tissue eosinophilia were pathologically high in a greater number of patients than peripheral blood eosinophilia. This trend was seen in all patterns of allergic rhinitis but was more evident in seasonal allergic rhinitis. The conclusion was reached that examination of local site and local secretions for eosinophilia is helpful in the diagnosis and differential diagnosis of allergic rhinitis.  相似文献   
3.
Foamability and foam stability of dairy-based emulsions, as a function of emulsion droplet size ranging from micron- to nanometre-scale, were investigated. Fat phase (10 % w/w of anhydrous milk fat, stearin or olein fraction) was mixed with 2 % w/w protein solution (sodium caseinate or whey protein concentrate) and homogenised at 3, 10 and 35 MPa to obtain emulsions having particle sizes of about 1.20, 0.60 and 0.20 μm, respectively. The emulsions were cooled down and aged at 4 °C for 48 h to promote crystallisation. No fat coalescence was observed in any of the emulsions, as particle size distribution remained the same upon aging and whipping. It was shown that the smaller the particle size, the higher was the apparent viscosity and the lower was the solid fat content. Higher solid fat content tended to yield better foamability and foam stability. Destabilisation of air cells happened fastest with nanosized fat particles, resulting in shorter half-life of foam.  相似文献   
4.
Improvements of melting resistance and quality by modification of pork-skin jelly through enzymatic cross-linking were studied, and the mechanism of quality improvement was discussed in this work. Gel strength, springiness and chewiness of modified gel increased significantly (P < 0.05). Transglutaminase (TGase) also improved the viscoelasticity, stability and melting resistance of gel system, as proved by rheological analysis. Sensory evaluation showed that increase in texture need to be moderate and the utilisation of 0.6% TGase was the most appropriate for pork-skin jelly. Significant effects of TGase on inducing protein cross-link and aggregation were confirmed by determining rheology during enzyme treatment and cross-linking extent of pork-skin soup. Correlation analysis showed TGase could improve melting temperature and texture by facilitating cross-linking. Covalent interaction based on ε-(γ-glutamyl)-lysine induced by TGase could play the main role in these improvements. This study suggested that TGase could be applied to design gelatin-based food for tailored quality properties through enzymatic cross-linking.  相似文献   
5.
6.
Levitation and free‐flight techniques applied to investigate the drying kinetics and morphology of single drops containing dissolved solids and suspensions are reviewed. A review of works related to receding interface model proposed to quantify the drying kinetics of single drops along with techniques to measure the kinetic parameters such as moisture diffusivity, thermal conductivity and specific heat capacity is presented. Problems associated with spray drying of sugar‐rich compounds are briefly discussed and possible links of stickiness and flavor retention with glass transition temperature (Tg), temperature history, drying rate and morphological changes including skin formation, as monitored through single drop experiments, are explored.  相似文献   
7.
V. Truong    B.R. Bhandari    T. Howes    B. Adhikari 《Journal of food science》2002,67(8):3011-3018
ABSTRACT: Physical aging of amorphous anhydrous fructose at temperature 5 °C and at 22 °C was studied using differential scanning calorimetry (DSC). The dynamic glass transition temperature, Tg0 for unaged samples was 16 °C and 13.3 °C for heating rate of 10 °C/min and 1 °C/min, respectively. The fictive temperature, Tf0 for unaged samples calculated by Richardson and Savill method was 12 °C, which is close to the dynamic value obtained from the lower DSC heating rate. The fictive temperature Tf of the aged fructose glasses at temperatures both below and above the transition region was fitted well by a non-exponential decay function (Williams-Watts form). Aging above the transition region (22 °C) for 18 d increased both the dynamic glass transition temperature Tg and the fictive temperature Tf. However, aging below the transition region (5 °C) for 1 d increased the dynamic glass transition temperature Tg but decreased the fictive temperature Tf.  相似文献   
8.
Static light scattering (SLS) was applied to monitor the rehydration process of milk protein concentrate (MPC) powder. The size distribution and volume concentration of the suspended powder particles were measured to quantify the dissolution kinetics of MPC powder. The results obtained showed that the low solubility index reported for MPC85 (85% protein) powder at room temperature was the consequence of slow dissolution kinetics rather than the presence of a large amount of insoluble material in the rehydrated powder. The rehydration process of MPC85 powder occurs in two overlapping steps: the disruption of agglomerated particles into primary powder particles and, simultaneously, the release of material from the powder particles into the surrounding aqueous phase. The latter process appeared to be the rate-limiting step of dissolution of MPC85 and was accelerated by an increase of the solvent temperature.  相似文献   
9.
Effects of chop length (shorter = 10 mm or longer = 19 mm) of alfalfa silage and corn silage were determined in 16 midlactation Holstein cows using a 4 × 4 Latin square design with a 2 × 2 arrangement of treatments. Experimental periods were 21 d long and consisted of 14 d of adaptation and 7 d of sampling. Cows received total mixed ration containing (dry matter basis) 44.0% barley grain-based energy supplement, 12.6% protein supplement, and 21.7% longer chop or shorter chop alfalfa silage and 21.7% longer chop or shorter chop corn silage. Reducing the chop length of alfalfa silage and corn silage reduced the average geometric particle length from 14.4 to 11.0 mm and from 14.2 to 10.4 mm, respectively. Reducing the chop length of both silages reduced the proportion of the diets retained by the 8-and 19-mm screen of the Penn State Particle Separator from 55.0 to 46.0% of dry matter. Reducing the alfalfa chop length increased total rumen volatile fatty acids at 4 to 5 h after feeding but did not affect rumen pH at 4 to 5 h after feeding, feed intake, and milk production. Reducing the corn silage chop length increased dry matter intake from 22.3 to 23.2 kg/d, increased rumen pH at 4 to 5 h after feeding from 6.12 to 6.20, but did not alter rumen volatile fatty acids at 4 to 5 h after feeding or milk production. Daily milk yield, milk fat percentage, and milk protein percentage averaged 38.2 kg/d, 2.62%, and 3.29%, respectively, across all diets. The low milk fat percentages suggest that all diets induced subacute ruminal acidosis (SARA), whereas the rumen pH did not indicate SARA. This discrepancy could be due to a difference in the time of rumen pH measurement and the time of the lowest rumen pH. Hence, the pH data need to be interpreted with caution. Diets could have induced SARA, because for all experimental diets the content of forage neutral detergent fiber was lower than recommended for barley grain-based diets.  相似文献   
10.
This study examined the retrogradation and digestibility relationship of fresh and stale cooked rice of three rice varieties: glutinous (TDK11) and non-glutinous (Doongara and floating rice). The effect of rice variety, degree of milling and retrogradation (staling) of cooked rice on the estimated glycaemic index was determined. Although high-glycaemic index values were obtained for fresh cooked rice of all varieties, staling rice at 4oC for 24 h showed positive effect on floating rice only, yielding intermediate-glycaemic index. The effect of staling on retrogradation rates was corroborated by changes in x-ray diffraction peaks. The thermal and textural properties of rice samples showed higher pasting temperature, final viscosity, and hardness, and lower peak viscosity and adhesiveness for fresh cooked non-glutinous varieties, which were also significantly affected by degree of milling, in terms of hardness, after retrogradation.  相似文献   
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