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91.
Vijay S. Tripathi 《Computers & Geosciences》1979,5(2):251-268
Computer-generated random numbers form the basis of most Monte-Carlo simulations and similar work. A FORTRAN program—RANTEST—was written that performs various statistical and empirical tests of randomness on uniform (0, 1) pseudorandom numbers. 相似文献
92.
A sixty-six year old diabetic male had a draining sinus tract from the lateral portion of a fourteen year old left herniorrhaphy scar. The diagnosis of sigmoidovesicocutaneous fistula was confirmed by a sinogram and the patient was treated in one stage with left hemicolectomy and resection of the fistula site from the dome of the bladder. To our knowledge this is the first report of a sigmoidovesicocutaneous fistula. 相似文献
93.
PtFe/NaY was characterized by Mössbauer spectroscopy after pretreatments in O2 and H2 at 700 K. Comparison of room-temperature spectra with those for standard Fe/NaY gave evidence for interaction between Pt and Fe. This result is discussed with respect to the phenomenon of chemical anchoring of Pt in zeolites. 相似文献
94.
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96.
Gyulassy A Natarajan V Pascucci V Hamann B 《IEEE transactions on visualization and computer graphics》2007,13(6):1440-1447
The Morse-Smale complex is an efficient representation of the gradient behavior of a scalar function, and critical points paired by the complex identify topological features and their importance. We present an algorithm that constructs the Morse-Smale complex in a series of sweeps through the data, identifying various components of the complex in a consistent manner. All components of the complex, both geometric and topological, are computed, providing a complete decomposition of the domain. Efficiency is maintained by representing the geometry of the complex in terms of point sets. 相似文献
97.
It is necessary to have excipients with excellent functional properties to compensate for the poor mechanical properties and low aqueous solubility of the emerging active ingredients. Therefore, around 80% of the current drugs are not suitable for direct compression and more advanced excipients are required. Further, conventional grades of excipients cannot accommodate the technologically advanced high speed rotary tablet presses which require a powder with excellent flow, good compressibility, compactibility, particle size distribution and homogeneity of the ingredients. Co-processed excipients have been created to enhance the functional properties of the excipients and reduce their drawbacks. Co-processing is defined as the combination of two or more excipients by a physical process. Co-processed excipients are adequate for direct compression since they become multifunctional and thus, their dilution potential is high eliminating the need for many excipients in a formulation. In some cases, they are able to hold up to 50% of the drug in a formulation rendering compacts of good tableting properties. This study describes and discusses the functionality enhancement of commercial and investigational excipients through co-processing. 相似文献
98.
In recent research, link stability is getting tremendous attention in mobile adhoc networks (MANETs), because of several impediments that occur in a reliable and robust network. Link stability metric is used to improve network performance in terms of end-to-end delay, data success delivery ratio (DSDR) and available route time (ART). Energy consumption, bandwidth and communication delay of major concern in ad hoc networks. A high mobility of MANET nodes reduces the reliability of network communication. In a dynamic networks, high mobility of the nodes makes it very difficult to predict the dynamic routing topology and hence cause route/link failures. Multicast in MANETs is an emerging trend that effectively improves the performance while lowering the energy consumption and bandwidth usage. Multicast routing protocol transmits a packet to multicast a group at a given time instant to achieve a better utilization of resources. In this paper, node mobility is considered to map better their movement in the network. So, the links with long active duration time can be identified as a stable link for route construction. Variation in signal strength is used to identify whether the direction of the node is towards or away from estimating node. We consider signal strength as QoS metric to calculate link stability for route construction. Efforts are made to identify the link with highly probable longer lifetime as the best suitable link between two consecutive nodes. We predict the movement time of nodes that define the route path to the node destination. Exata/cyber simulator is used for network simulation. The simulation results of the proposed routing protocol are compared with on-demand multicast routing protocol and E-ODMRP, which works on minimum hop count path. Analysis of our simulation results has shown improvement of various routing performance metrics such as DSDR, ART, routing overhead and packet drop ratio. 相似文献
99.
Nucleate boiling at high heat fluxes has been studied numerically by solving the equations governing conservation of mass, momentum and energy in the liquid and vapor phases. The interface is captured by using the level set method based on a sharp-interface representation. The evaporative heat flux from the liquid microlayer is incorporated in the analysis. The effects of wall superheat, number density of nucleation sites and waiting period on the bubble dynamics and heat transfer in nucleate boiling are investigated. The heat fluxes obtained from the present numerical simulations are compared with the experimental data reported in the literature. 相似文献
100.
In this paper, an optimal control technique for n-phase permanent-magnet (PM) machines under various open circuit faults is presented. Under the fault conditions, the currents in the healthy phases are controlled to compensate phase loss and to produce the required output torque. The proposed control technique ensures continuous operation of the machines while producing minimum torque ripples and minimum stator ohmic loss. The control technique is based on the instantaneous power balance theory. To set the summation of the phase currents equal to zero, a constraint is incorporated in the derivation of the control technique. A five-phase PM machine is considered to demonstrate the proposed open circuit fault-tolerant control strategy. Simulation and experimental results are provided for validation. 相似文献