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121.
Carrot (Daucus carota) can be highly perishable and difficult to preserve fresh for long periods at ambient temperature and humidity. Studies on grated carrots were carried out for the development of a shelf‐stable moist‐preservation process based on infusion of additives using hurdle technology. Additives comprising 3.0% sodium chloride (to reduce water activity [Aw] to 0.94), 0.9% citric acid (to reduce pH to below 4.5), 1.0% sodium citrate and 0.2% sodium benzoate (as antimicrobial agents) were followed by partial dehydration. The product was stored in flexible polymeric pouches. The physical, chemical and pathological stability was monitored during storage at ambient temperatures (19–33C). The partially dehydrated grated carrots (moisture 66.2%) were acceptable for more than six months at ambient temperature with the retention of carotenoid up to 82.5%. The product was microbiologically safe throughout the study.  相似文献   
122.
During the course of development of Mechanical Engineering, a large number of mechanisms (that is, linkages to perform various types of tasks) have been conceived and developed. Quite a few atlases and catalogues were prepared by the designers of machines and mechanical systems. However, often it is felt that a clustering technique for handling the list of large number of mechanisms can be very useful, if it is developed based on a scientific principle. In this paper, it has been shown that the concept of fuzzy sets can be conveniently used for this purpose, if an adequate number of properly chosen attributes (also called characteristics) are identified. Using two clustering techniques, the mechanisms have been classified in the present work and in future, it may be extended to develop an expert system, which can automate type synthesis phase of mechanical design. To the best of the authors?? knowledge, this type of clustering of mechanisms has not been attempted before. Thus, this is the first attempt to cluster the mechanisms based on some quantitative measures. It may help the engineers to carry out type synthesis of the mechanisms.  相似文献   
123.
The effects of time delays on collocated as well as non-collocated point control of classically damped discrete dynamic systems have been examined. Controllers of PID type nave been considered. Analytical estimates of time delays to maintain/obtain stability for small gains have been given. Several new results dealing with the effect of time delays on collocated and non-collocated control designs are obtained. It is shown that undamped structural systems cannot be stabilized with pure velocity (or integral) feedback without time delays while using a controller that is not collocated with the sensor, when the mass matrix is diagonal. However, with the appropriate choice of time delays, for certain classes of commonly occurring structural systems, stable non-collocated control can be achieved. Analytical results providing the upper bound on the controller's gain necessary for stability have been presented. The theoretical results obtained are illustrated and verified with numerical examples.  相似文献   
124.
The selection of parts and machines poses an important problem in the design and planning phases of cellular manufacturing and flexible manufacturing systems. In most real-life situations, this grouping invariably leads to 'bottleneck’ parts and machines. This paper discusses a method of identifying the minimal number of bottle-neck cells (machines or parts) which, when dealt with through either duplication of machines or subcontracting of parts, will result in perfect part-machine groupings with no overlap. The polynomially bounded algorithms used in the analysis are oriented towards finding minimal cut-nodes in either partition of the bipartite part-machine graph.

  相似文献   
125.
By extending the minimum spanning tree (MST) clusterization algorithm for the binding energy cut, the isospin asymmetry dependence of directed flow for isospin sensitive isobar pairs (neutrons-protons, 3H-3He) is studied from low towards high incident energies. The modified clusterization method (MSTB) has the advantage to identify the fragments at quite early time. It enhances (reduces) the production of free nucleons (fragments) over MST method. The directed flow of isobaric pair 3H-3He is more sensitive towards isospin asymmetry caused by MSTB than isobaric pair n-p. This sensitivity becomes quite strong towards the high incident energy and neutron-rich reaction system. In conclusion, the inclusion of binding energy in clusterization method for the flow studies has been uniquely important for understanding the isospin physics, especially for high density behavior of symmetry energy.  相似文献   
126.
Abstract

The SNePS inference engine is optimized for deductive efficiency, i.e. all beliefs acquired via inference are added to the agent's beliefs so that future queries may be answered by a retrieval rather than rederivation. An assumption-based truth maintenance system keeps track of the derivation histories of derived beliefs. We show how such an architecture simplifies the ontology of prepositional representations of plans; acts; preconditions, and effects of actions. In addition, the deductive efficiency of the basic system automatically extends itself to efficient search of plans, and hierarchical plan decompositions.  相似文献   
127.
The aim of this paper is to investigate the effect of sintering temperature and time on the properties of Fe–Al2O3 composite (5 wt% Al2O3; 95 wt% Fe) prepared by powder metallurgy process. X-ray diffraction, microstructure, density, hardness and compressive strength of prepared samples have been investigated. XRD studies show the presence of Fe and Al2O3 along with iron aluminate phase. Iron aluminate is formed as a result of reactive sintering between iron and alumina particles. Microstructural examination of the specimen showed a dense structure with nanosize dispersion of the reinforcement of ceramic phase. Density as well as hardness of specimens depend on the formation of iron aluminate phase, which in turn depends on sintering temperature and time.  相似文献   
128.
This paper presents experimental results for cold testing of a gyrotron open resonator. Experiments were carried out to measure resonant frequency and their particular quality factor for TE mode at the frequency 42 GHz. The perturbation technique was used to determine the axial, radial and azimuthal electric field profile for identification of TE031 mode at operating frequency 42 GHz. The good agreement between experimental results and theoretical studies was found. The results verify the design and fabrication of the specific gyrotron cavity.  相似文献   
129.
130.
Hopfield networks are a class of neural network models where non-linear graded response neurons organized into networks with effectively symmetric synaptic connections are able to implement interesting algorithms, thereby introducing the concept of information storage in the stable states of dynamical systems. In addition to opening up the possibility of using system dynamics as a vehicle to gain potentially useful insights into the behaviour of such networks, especially in the field or nonelectrical engineering, we study the dynamics of the state-space trajectory as well as time domain evolution of sensitivities of the states with respect to circuit parameters.  相似文献   
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