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101.
This paper presents the development of a reliable heat index (HI) measurement system for evaluating the thermal comfort of a particular building or a particular area. The HI is an index that combines air temperature and relative humidity (RH) to determine the human-perceived equivalent temperature. To measure the air temperature and RH, temperature to digital converter and RH to voltage converter is used. HI is calculated online with the help of embedded firmware of the microcontroller. This calculated value is then transferred to the computer through standard RS 232 serial port. The same sensor node is tested with the RS 485 network standard by changing the transceiver of the node. The system is calibrated using four standard saturated binary salt solutions. 相似文献
102.
103.
The Drosophila hook gene encodes a novel component of the endocytic compartment. Previously identified hook alleles, which still expressed truncated Hook proteins, affected the accumulation of internalized transmembrane ligands into multivesicular bodies (MVBs). To determine the hook null phenotype, we isolated nine new hook alleles on the basis of their characteristic hooked-bristle phenotype. At least one of these alleles, hk11, is a complete loss-of-function allele. Flies carrying the hk11 allele are viable and fertile but neither transmembrane ligands nor soluble ligands accumulate in MVBs. This effect on endocytosed ligands can be mimicked by the expression of Hook proteins truncated for the N- and C-terminal domains flanking the central coiled-coil region. The importance of all three domains for Hook function was confirmed by their conservation between two Drosophila and two human Hook proteins. 相似文献
104.
A new catalyst WO3/ZrO2–Ce0.6Zr0.4O2 (15 wt % WO3/ZrO2:Ce0.6Zr0.4O2 = 50:50) has been developed for the selective catalytic reduction of NO with NH3. The redox component Ce0.6Zr0.4O2 was dispersed on the surface of acidic WO3/ZrO2 by the solution combustion method showing the best NO x reduction efficiency among the catalysts prepared by various modes of mixing of the components. The catalyst has been characterized by XRD, Raman spectroscopy and NH3-TPD. A NO x reduction efficiency of more than 90 % was obtained between 300 and 500 °C at α = NH3,in/NO x,in = 1. The catalyst showed stable NO x reduction efficiency after hydrothermal ageing at 700 °C. Sulfur poisoning promoted the NO x reduction efficiency at high temperatures at the expense of a reduced activity at lower temperatures, but the catalyst could be fully regenerated by heating in O2 at 650 °C. 相似文献
105.
L. Král M. Šimandl 《International Journal of Adaptive Control and Signal Processing》2011,25(11):949-964
The article deals with a challenging problem of adaptive control design for multivariable stochastic systems with a functional uncertainty. Model of the system is based on multi‐layered perceptron neural networks where both the unknown parameters and the structure are found in real time without a necessity of any off‐line training process. The unknown parameters are estimated by a global estimation method, the Gaussian sum filter, and the structure of the neural network model is optimized by a proposed pruning method. The control law is based on a bicriterial approach to the suboptimal dual control. Two individual criteria are designed and used to introduce conflicting efforts between the estimation and control; probing and caution. A comparison of the proposed dual control and its alternative with an implementation of the pruning algorithm is shown in a numerical example. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
106.
An objective of the study was to identify leaf morphophysiological characteristics indicative of high aboveground woody biomass production of Salix clones growing in the vegetation filter of a wastewater purification system. It was hypothesized, that in these extra irrigated stands, the characteristics of photosynthesis are stronger determinants of the production than the characteristics of leaf water relations. The biomass production of the clones was correlated with numerous characteristics of leaf water relations and photosynthesis. Significant correlation was found between the biomass production and the following characteristics of top foliage leaves: daily decrease in water potential, stomatal conductance, stomatal sensitivity to increase in light intensity, and hydraulic conductance (positive); daily minimum and maximum water potentials, instantaneous water use efficiency, and stomatal sensitivity to decrease in leaf water potential (negative); maximum rate of photosynthetic electron transport, chlorophyll content, and the partitioning coefficient for leaf nitrogen into bioenergetics associated with electron transport (positive). In the most productive clones, the vertical gradient (through foliage) of values of almost all the characteristics was the smallest. The biomass correlated more strongly with the characteristics of photosynthesis light stage than with the characteristics of water relations. We conclude that the characteristics of photosynthesis light stage – high maximum rate of photosynthetic electron transport, high chlorophyll content, and also flat vertical gradient (through foliage) in values of the characteristics could be the strongest indicators of high biomass production of Salix clones growing in vegetation filter. 相似文献
107.
Avdhesh Kr. Sharma 《Solar Energy》2008,82(10):918-928
The thermodynamic and kinetic modeling of char reduction reactions in a downdraft (biomass) gasifier has been presented. Mass and energy balance are coupled with equilibrium relations or kinetic rate parameters (using varying char reactivity factor) in order to predict status of un-converted char in addition to gas composition, calorific value, conversion efficiency, exit gas temperature, endothermic heat absorption rate and gasifier power output. Both modeling predictions are compared against experimental data for their validity. The influence of char bed length and reaction temperature in reduction zone has been examined. CO and H2 component, calorific value of product gas and the endothermic heat absorption rate in reduction zone are found to be sensitive with reaction temperature, while char bed length is less sensitive to equilibrium predictions. For present case, all char conversion takes place at critical reaction temperature of 932 K for equilibrium, while for kinetic modeling critical reaction temperature and critical char bed length of 950 K and ~25 cm have been identified, comparing the predictions. The critical reaction temperatures and critical char bed length also depend on inlet components composition and initial temperature supplied to the reduction reaction zone model. 相似文献
108.
Optimum Shape of Packings for Columns Packings, dumped and orderly arranged as well, are applied in an increasing amount for mass transfer processes for waste water and off gas purification in the field of technological environmental protection. The choice of suitable column internals is an important prerequisite for optimum operation of those plants. Based on the performance characteristics of modern packing internals the criteria will be discussed, which are decisive for optimum column choice. 相似文献
109.
The authors draw attention to their favourable results of disconnection in haemorrhage of oesophageal varices. This favourable result applies to immediate results as well as long-term results. They emphasize in particular the fact that disconnection can be used also when other methods are not feasible for various reasons. This fact is demonstrated by the authors on three patients whose complicated history and general condition were such that disconnection was the only solution of the situation. 相似文献
110.
X-ray diffraction measurements were carried out on powdered single crystals of nearly stoichiometric Fe3Si. The experimental data obtained in the temperature range from room temperature up to 750‡ C in terms of long-range order,
thermal expansion, phase transition and Debye temperature (together with values of the Curie temperature) support the existence
of two modifications of the DO3 structure for Fe-26 at% Si alloys and a phase transition in the DO3 structure field at 595‡ C. The high-temperature modification has a smaller thermal expansion coefficient, a higher Curie
temperature and a higher Debye temperature. 相似文献