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991.
Currently, two motivators are effecting change in power systems education. First, the industry's transition to a more competitive environment is requiring changes in the content and pedagogy of power systems education. Second, engineering education as a whole is seeking to modify its curriculum to reflect a better balance between science and education in order to better meet the needs of industry. These curricular changes are largely a result of revised Accreditation Board for Engineering and Technology (ABET) accreditation requirements. In response to these changes, new curriculum and analysis tools were developed for a power systems capstone design course. The project integrates market economics and socio-political considerations with transient stability analysis and transmission planning. A power systems analysis package and an economic analysis tool were developed for use with this project. Student evaluations of the course in which the project was implemented indicate that the curriculum successfully addresses a broad range of ABET accreditation criteria. 相似文献
992.
S. O. Shiryaeva A. I. Grigor’ev V. A. Koromyslov A. S. Golovanov 《Technical Physics Letters》2002,28(1):41-43
A dispersion equation for the capillary oscillations of a charged drop of incompressible liquid possessing a finite electric
conductivity is derived with an allowance for the energy lost as a result of the electromagnetic wave emission. The magnitude
of the electromagnetic radiation losses of the oscillating drop linearly increases with the electric conductivity and the
surface mobility of charge carriers. 相似文献
993.
V. V. Skurat N. M. Shiryaeva N. K. Myshkina A. A. Gvozdev G. Z. Serebryanyi N. B. Golikova 《Journal of Engineering Physics and Thermophysics》2002,75(5):1200-1206
Unsatisfactory conditions of storage of decontamination waste (DW) in the storages formed in the territory of Belarus after the Chernobyl accident require the evaluation of the level of protection of the environment and population. The potential hazard of the decontamination waste burial grounds (DWBGs) has been evaluated based on the use of a generalized multichamber model that was verified by comparing the calculation results and the results obtained by the American (GW SCREEN) model. The characteristics of the 24 largest and most hazardous DWBGs are given and the evaluations of their safety are presented. The zones of influence of these storages, whose size varies from 100 to 330 m, have been determined. The reliability of the prediction evaluation of a possible hazardous radioactive contamination of water near the storages has been verified using the Dudichi DWBG as an example. 相似文献
994.
V. G. Gorobets 《Journal of Engineering Physics and Thermophysics》2002,75(5):1130-1138
A mathematical model of heat transfer has been developed and numerical calculations for a vertical surface with discrete fins arranged in staggered order have been carried out. The model accounts for the influence of the heat-conduction properties of the finning material and of the fin size on the conditions of heat transfer. A comparison of the results obtained with the existing numerical and experimental data has been made. This comparison shows that the discretization intensifies the heat-transfer process by 50–70%, and neglect of the heat-conduction properties of the fins leads to overstated values of the removed heat fluxes. 相似文献
995.
996.
The paper presents investigations of the solution infiltration depth in porous materials measured using changes in the velocity of the longitudinal ultrasonic wave versus penetration depth. 相似文献
997.
The concept of optical burst switching (OBS) aims to allow access to optical bandwidth in dense wavelength division multiplexed (DWDM) networks at fractions of the optical line rate to improve bandwidth utilization efficiency. This paper studies an alternative network architecture combining OBS with dynamic wavelength allocation under fast circuit switching to provide a scalable optical architecture with a guaranteed QoS in the presence of dynamic and bursty traffic loads. In the proposed architecture, all processing and buffering are concentrated at the network edge and bursts are routed over an optical transport core using dynamic wavelength assignment. It is assumed that there are no buffers or wavelength conversion in core nodes and that fast tuneable laser sources are used in the edge routers. This eliminates the forwarding bottleneck of electronic routers in DWDM networks for terabit-per-second throughput and guarantees forwarding with predefined delay at the edge and latency due only to propagation time in the core. The edge burst aggregation mechanisms are evaluated for a range of traffic statistics to identify their impact on the allowable burst lengths, required buffer size and achievable edge delays. Bandwidth utilization and wavelength reuse are introduced as new parameters characterizing the network performance in the case of dynamic wavelength allocation. Based on an analytical model, upper bounds for these parameters are derived to quantify the advantages of wavelength channel reuse, including the influence of the signaling round-trip time required for lightpath reservation. The results allow to quantify the operational gain achievable with fast wavelength switching compared to quasistatic wavelength-routed optical networks and can be applied to the design of future optical network architectures 相似文献
998.
We formulate the inverse problem of scattering of electromagnetic fields by thin defects and analyze numerical algorithms used for its solution. It is shown that, in the two-dimensional case, the shape of a thin defect is completely determined by the scattered field given on a certain curve for a fixed value of the wave number. For the solution of the inverse scattering problem, we propose to use the procedure of iterative regularization based on the gradient methods. We deduce expressions for the Fréchet derivative of the operator of direct scattering problem with Dirichlet conditions imposed on the surface of a scatterer. 相似文献
999.
1000.