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51.
There are two major difficulties in real‐time multicast connection setup. One is the design of an efficient distributed routing algorithm which optimizes the network cost of routing trees under the real‐time constraints. The other is the integration of routing with admission control into one single phase of operations. This paper presents a real‐time multicast connection setup mechanism, which integrates multicast routing with real‐time admission control. The proposed mechanism performs the real‐time admission tests on a cost optimal tree (COT) and a shortest path tree (SPT) in parallel, aiming at optimizing network cost of the routing tree under real‐time constraints. It has the following important features: (1) it is fully distributed; (2) it achieves sub‐optimal network cost of routing trees; (3) it takes less time and less network messages for a connection setup. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
52.
Biopreservation is defined as using microbes, their constituents, or both to control spoilage while satisfying consumer demand for clean-label products. The study objective was to investigate the efficacy of bacterial cultures in biopreserving cottage cheese against postprocessing fungal contamination. Cottage cheese curd and dressing were sourced from a manufacturer in New York State. Dressing was inoculated with 3 different commercial protective cultures—PC1 (mix of Lacticaseibacillus spp. and Lactiplantibacillus spp.), PC2 (Lacticaseibacillus rhamnosus), and PC3 (Lactic. rhamnosus)—following the manufacturer recommended dosage and then mixed with curd. A control with no protective culture was included. Nine species of yeast (Candida zeylanoides, Clavispora lusitaniae, Debaryomyces hansenii, Debaryomyces prosopidis, Kluyveromyces marxianus, Meyerozyma guilliermondii, Pichia fermentans, Rhodotorula mucilaginosa, and Torulaspora delbrueckii) and 11 species of mold (Aspergillus cibarius, Aureobasidium pullulans, Penicillium chrysogenum, Penicillium citrinum, Penicillium commune, Penicillium decumbens, Penicillium roqueforti, Mucor genevensis, Mucor racemosus, Phoma dimorpha, and Trichoderma amazonicum) were included in the study. Fungi strains were previously isolated from dairy processing environments and were inoculated onto the cheese surface at a rate of 20 cfu/g. Cheese was stored at 6 ± 2°C. Yeast levels were enumerated at 0, 7, 14, and 21 d postinoculation. Mold growth was visually observed on a weekly basis through d 42 of storage and imaged. Overall, the protective cultures were limited in their ability to delay the outgrowth in cottage cheese, with only 8 of the 20 fungal strains showing an effect of the cultures compared with the control. The protective cultures were not very effective against yeast, with only PC1 able to delay the outgrowth of 3 strains: D. hansenii, Tor. delbrueckii, and Mey. guilliermondii. The efficacy of these protective cultures against molds in cottage cheese was more promising, with all protective cultures showing the ability to delay spoilage of at least 1 mold strain. Both PC1 and PC2 were able to delay Pen. chrysogenum and Pho. dimorpha outgrowth, and PC1 also delayed Pen. commune, Pen. decumbens, and Pen. roqueforti to different extents compared with the controls. This study demonstrates that commercial lactic acid bacteria cultures vary in their performance to delay mold and yeast outgrowth, and thus each protective culture should be evaluated against the specific strains of fungi of concern within each specific dairy facility.  相似文献   
53.
The problem of robust stabilization of nonlinear systems with feedback linearizable nominal part and norm-bounded nonlinear uncertainties is investigated. Necessary and sufficient conditions are obtained for robust stabilization of such systems. A design procedure is developed which combines feedback linearization technique and quadratic stabilization via linear feedback to achieve robust global asymptotic stability. © 1997 by John Wiley & Sons, Ltd.  相似文献   
54.
The present study proposes that affiliation motivation plays a key role in driving Snapchat use. Constructs from the technology acceptance and relational maintenance literature were incorporated to examine the normative and interpersonal goals associated with Snapchat use. It was hypothesized that these two models and their associated constructs illustrate behavioral and cognitive phenomena that are tied to and fueled by the innate human desire to affiliate with others. The study was conducted using an online survey at a large, Midwestern university with a final student sample of 236. Perceived playfulness, subjective norm, trust, and critical mass (TAM constructs), as well as assurances and positivity (RM behaviors), were all found to be significantly and positively correlated with Snapchat use. This study highlights the interpersonal value of Snapchat and adds to the existing literature examining various information and communication technologies (ICTs) as tools for relational maintenance.  相似文献   
55.
During the past years, various principal component analysis algorithms have been developed. In this paper, a new approach for local nonlinear principal component analysis is proposed which is applied to capture voice conversion (VC). A new structure of autoassociative neural network is designed which not only performs data partitioning but also extracts nonlinear principal components of the clusters. Performance of the proposed method is evaluated by means of two experiments that illustrate its efficiency; at first, performance of the network is described by means of an artificial dataset and then, the developed method is applied to perform VC.  相似文献   
56.
We present a new method for testing digital CMOS integrated circuits. The new method is based on the following premise: monitor the switching behavior of a circuit as opposed to the output logic state. We use the transient power supply current as a window of observability into the circuit switching behavior. A method for isolating normal switching transients from those which result from defects is introduced. The feasibility of this new testing approach is investigated by conducting several experiments involving the design of integrated circuits with built-in defects, fabrication, and physical testing. The results of these experiments show this new test method to be a promising one for detecting defects that can escape stuck-at testing andI DDQ testing.  相似文献   
57.
Wireless networks suffer from battery discharging specially in cooperative communications when multiple relays have an important role but they are energy constrained. To overcome this problem, energy harvesting from radio frequency signals is applied to charge the node battery. These intermediate nodes have the ability to harvest energy from the source signal and use the energy harvested to transmit information to the destination. In fact, the node tries to harvest energy and then transmit the data to destination. Division of energy harvesting and data transmission can be done in two algorithms: time-switching-based relaying protocol and power-splitting-based relaying protocol. These two algorithms also can be applied in delay-limited and delay-tolerant transmission systems. The previous works have assumed a single relay for energy harvesting, but in this article, the proposed method is concentrated on improving the outage probability and throughput by using multiple antennas in each relay node instead of using single antenna. According to our simulation results, when using multi-antenna relays, ability of energy harvesting is increased and thus system performance will be improved to great extent. Maximum ratio combining scheme has been used when the destination chooses the best signal of relays and antennas satisfying the required signal-to-noise ratio.  相似文献   
58.
59.
Fabrication of Ge-based thermocouple on polyethylene-terephthalate (PET) plastic substrates is reported. The amorphous Ge film, deposited using electron beam evaporation, is post treated to form a polycrystalline film. The annealing process has been performed at temperatures ranging from 120/spl deg/C to 175/spl deg/C and study of physical characteristics of Ge films using XRD and SEM confirms its crystallinity. A value of 100 /spl mu/V//spl deg/C is extracted for the Ge-Al junctions. The thermocouple fabrication and its response to flow are reported. A novel approach is described to perform the micromachining of PET substrates for the formation of craters and membranes. Di-methyl-formamide (DMF) is used as the solvent of the PET substrate, masked with a Ge/Cu multilayer. An average chemical etch rate of 12 /spl mu/m/h is achieved in the presence of 6.5 mW/cm/sup 2/ of 360-nm UV at ambient temperature.  相似文献   
60.
Makki S  Wang Z  Leger JR 《Applied optics》1997,36(20):4749-4755
A diffractive optical element is used to relay complex laser beam profiles by phase conjugation. It has the advantage over a conventional afocal system of avoiding light concentration at the intermediate focal point. Theoretical and experimental results show that the image quality is a function of alignment errors and mode-size changes. When the optical system is within the calculated tolerances, the diffractive optic reproduces images of high quality.  相似文献   
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