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61.
A sequential fixed-lag smoothing algorithm is derived here for linear systems, when it is assumed that the measurements contain the sum of signals with known time delays and are corrupted by coloured noise. The innovations approach is used to derive the algorithm that is suitable for online computations.  相似文献   
62.
63.
Thermal decomposition of powdered ammonium perchlorate (AP), polystyrene (PS) and APPS propellant, catalysed by freshly-prepared CuCr2O4 and mixtures of CuCr2O4 and CuO, has been studied with a low concentration (1% by mass) of the catalysts. It appears that decomposition is increased due to heterogeneous catalysis. The kinetics of thermal decomposition of AP in the presence of CuCr2O4 in the orthorhombic region of AP have also been studied.  相似文献   
64.
This paper presents a M6800 microprocessor based hardware monitor for measuring certain selected parameters of the EC-1030 computer system. The motivation for this work was to get an insight into the operation of the system under the present work load and use these results towards improvement and design studies. The three main classes of quantitative indices of computer system performance/productivity, responsiveness and use have been measured using hardware and software tools. This paper describes the hardware monitor design and discusses the measurements made.  相似文献   
65.
Neural Computing and Applications - Marston’s load theory is commonly used for understanding the soil–conduit interaction. However, there are no practical methods available which can...  相似文献   
66.
Arching in Soils Applied to Inclined Mine Stopes   总被引:3,自引:0,他引:3  
Determination of stress distribution, giving due consideration to arching mechanism within minefill stopes, is of great importance because of its influence on the ground stability, ore recovery, and cost effectiveness. Most of the past studies on the stress determination have been applied to vertical stopes, and there is a lack of research study, especially analytical work, on inclined stopes. This study provides an analytical expression for the vertical stress at any depth within the inclined backfilled stopes by incorporating an arching effect within the backfill. Comparatively, the results obtained from this study agree well with other limited analytical and numerical results reported in the literature. A parametric study is undertaken to investigate the effect of various parameters involved in the proposed analytical expression. The results obtained reveal that stope geometry, fill properties, and stope inclination are critical factors in predicting the stress distribution in mine stopes.  相似文献   
67.
A sophisticated micro-pulse lidar (MPL) has been designed and developed for the study of the atmospheric boundary layer (ABL) and clouds. The developed MPL uses a low energy pico-second pulsed Nd:YAG laser at 532 nm. The conventional receiver optic is used along with a photomultiplier tube in single photon detection mode. Stanford Research Systems' multi-channel scalar (MCS) is used with a personal computer for data acquisition. Due to the short laser pulse and a fast MCS, a spatial resolution of 0.75 m has been achieved. The control circuit has been designed to sense telescope cover status (open or closed) to avoid any mistakes in dark count and background data acquisition. The complete control software and Graphical User Interface (GUI) has been developed in Visual Basic. The lidar system has been tested both for its functionality to detect the variation in ABL and cloud height and also for its capability to acquire continuous night-time data without user interaction. In this article the design details and some preliminary results are discussed.  相似文献   
68.
In this work, we report electronic structure calculations aimed at computing the linear optical absorption spectrum and static dipole polarizablity of a newly proposed boron-based planar aromatic compound borozene (B 12 H 6). For the purpose, we use the semiempirical INDO model Hamiltonian, accompanied by large-scale correlation calculations using the multi-reference singles-doubles configuration-interaction (MRSDCI) approach. We present detailed predictions about the energetics, polarization properties, and the nature of many-particle states contributing to various peaks in the linear absorption spectrum. Our results can be used to characterize this material in future optical absorption experiments. We also argue that one can deduce the aromaticity of the cluster from the optical absorption and static polarizability results.  相似文献   
69.
As resources of electricity generation in India are not sufficient, this paper analyses the potential of electricity import from neighboring countries to meet the future electricity requirements of India. Based on the data of electricity generation, consumption, and future generation potential, we work out projected electricity generation/ demand of India and its neighboring countries by 2050 to identify the possibility of India’s cross-border electricity trading with its neighboring countries, more particularly the electricity import potential.  相似文献   
70.
An improved form of the Peng-Robinson cubic equation of state has been proposed. The temperature dependence of the attractive term has been modified so as to accurately represent vapor pressures of several fluids with large acentric factors from triple point to close to the critical point. The prediction of saturated liquid volume is also improved by introducing volume translation term in the equation of state. Comparisons of theoretical results with experimental data are made for the vapor/liquid phase equilibria of 44 pure fluids including nonpolar, polar and associating fluids. Our results show that the modified Peng-Robinson equation of state can represent accurately saturated vapor pressures of the fluids investigated in this paper, and it is more accurate than the Peng-Robinson equation of state and its earlier modifications due to Stryjek and Vera (1986) and Twu et al. (1995rpar;. Incorporation of the volume translation term in the equation of state has been found to improve the accuracy of saturated liquid volume significantly.  相似文献   
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