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101.
This paper describes an algorithm and a computer program which solves numerically (virtually exactly) equations of the restricted open-shell Hartree-Fock and Hartree-Fock-Slater model for diatomic molecules 相似文献
102.
This paper sets out the results of mathematical modeling and numerical simulations of the off-design (part-load) operation of the solid oxide fuel cell hybrid system (SOFC-HS). 相似文献
103.
Metadata requirements for digital museum environments 总被引:1,自引:0,他引:1
Manjula Patel Martin White Nicholaos Mourkoussis Krzysztof Walczak Rafal Wojciechowski Jacek Chmielewski 《International Journal on Digital Libraries》2005,5(3):179-192
We describe a system which addresses all the processes involved in digitally acquiring, modelling, storing, manipulating and creating virtual exhibitions from 3D museum artefacts. More specifically, we examine the significance of metadata in enabling and supporting all of these processes and describe the extensive facilities provided for authoring, maintaining and managing metadata. The development of the system has been heavily influenced by factors relating to interoperability, standards, museum best practice and feedback from two museum pilot sites. Finally, we briefly consider the system in the wider context of applications such as virtual learning environments and distributed repositories of archives. 相似文献
104.
Jacek M. Czaplicki 《Microelectronics Reliability》1985,25(4):695-698
In the paper the model of reliability diagnostic of renewal objects which exploitation process can be described as the interrupting renewal process with the finite time of repair is discussed. The essential relationships between reliability of object and diagnostic parameters are presented. 相似文献
105.
Air-coupled ultrasonic sources are relatively inefficient because the high impedance mismatch at the air/solid boundary means that most of the input energy (in air) is reflected at this boundary. The objective of this research is to increase efficiency—specifically an increase in ultrasonic signal amplitude—by designing and building a focused, 2D-array of electrostatic transducers (individual diameters of 38 mm). The operating frequency of this array is in the range of 50–100 kHz; this range is selected for civil infrastructure applications. Numerical simulations are used to design an array by modeling the pressure field in air, and then optimizing an array consisting of 20 transducers to create a line-source. An array is then built (following this design) and the emitted pressure field (in air) of the as built array is measured with a microphone and compared to the pressure field predicted by the numerical model. Finally, the as built focused array is used as an ultrasonic source, and its robustness is verified by comparing the numerical simulation of a transient line-load on an elastic half-space with (completely non-contact) experimentally measured values. There is excellent agreement between these two representations, which confirms the possibility of developing a completely non-contact, scanning ultrasonic system in the 50–100 kHz range. 相似文献
106.
In this paper we present a computational model of electrical conductivity processes via variable range hopping of electrons between localized states (‘sites’) in quasi one-dimensional disordered systems. For two, slightly different models, the temperature dependence of the conductivity of parallel connected systems of filaments and of quasi-infinite, single filaments are discussed and compared with theoretical and experimental results. 相似文献
107.
Jacek A. Michalski 《化学工程与技术》1995,18(6):434-439
A theoretical analysis is presented for the time-dependent vertical motion of spherical particles in a gas stream. Laminar, transitional and turbulent flows are considered, and equations are developed to predict particle velocity and distance travelled as functions of time in both stagnant and slowly-moving gases. In both cases the equations are shown not to be universally applicable, and algorithms for estimating the limits within which they remain valid are briefly presented. 相似文献
108.
This paper describes two ideas and sample simulation results of a heuristic reinforcement-learning system and its application to the problem of digital computer control of a simple nuclear plant model. The idea of the system is interconnection between the well known reactor control heuristic rules [8,9], and the reinforcement learning algorithms [4,5]. The control signal is proposed as a vector depending on complex physical properties of the plant. Such an approach is far more flexible than deterministic or stochastic techniques when dealing with unknown processes and novel control situations. 相似文献
109.
110.
Jacek Chroscielewski Zbigniew Cywinski Ireneusz Kreja Stanislaw Uminski 《Computers & Structures》1983,17(1):37-44
Computer aided finite element analysis has been applied to evaluate the structural behavior of a solid plate representing statically certain box-type construction of a dry dock gate. Possible comparison of particular results following from different procedures, valid for constant plate stiffness and rigid supports, has been performed and the distribution of reactions for variable plate stiffness, within two different numerical accuracies, has been studied. For practical requirements the nonlinear elastic flexibility of dock gate packing has been taken into account and an adequate numerical step-by-step approach, satisfying the considered material characteristics, developed. For last case the deflections, reactions, and internal forces have been examined in detail and a comparison with those for rigid supports presented. 相似文献