high price increase due to the immobilization of the fuel in the waste fuel nuclear reactor pools.docx

1、high price increase due to the immobilization of the fuel in the waste fuel nuclear reactor poolsvelocity, and current density. Mathematically the model forms a system of differential-algebraic equations (DAEs), which is solved computationally. The model is designed with process-control applications

2、 in mind, although it can certainly be applied more widely. Although the physical model is computationally efficient, it is still too costly for incorporation directly into real-time process control. Therefore, system-identification techniques are used to develop reduced-order, locally linear models

3、 that can be incorporated directly into advanced control methodologies, such as model predictive control (MPC). The paper illustrates the physical model and the reduced-order linear state-space model with examples.Article OutlineNomenclature1. Introduction2. Model development 2.1. Fuel flow, overall

4、 mass continuity2.2. Fuel flow, species continuity equations2.3. Fuel flow, thermal energy2.4. Anode bi-layer model2.5. MEA energy balance2.6. Cathode air conservation equations2.7. Electrochemistry3. Implementation4. Example model results 4.1. Steady-state results4.2. Transient simulations5. Linear

5、 identification of the SOFC stack 5.1. Subspace system identification5.2. Illustration of linear system identification6. ConclusionReferences937Recent advances in nuclear powered electric propulsion for space explorationOriginal Research ArticleEnergy Conversion and Management, Volume 49, Issue 3, M

6、arch 2008, Pages 412-435R. Joseph Cassady, Robert H. Frisbee, James H. Gilland, Michael G. Houts, Michael R. LaPointe, Colleen M. Maresse-Reading, Steven R. Oleson, James E. Polk, Derrek Russell, Anita SenguptaClose preview| Related articles|Related reference work articles AbstractAbstract | Figures

7、/TablesFigures/Tables | ReferencesReferences AbstractNuclear and radioisotope powered electric thrusters are being developed as primary in space propulsion systems for potential future robotic and piloted space missions. Possible applications for high-power nuclear electric propulsion include orbit

8、raising and maneuvering of large space platforms, lunar and Mars cargo transport, asteroid rendezvous and sample return, and robotic and piloted planetary missions, while lower power radioisotope electric propulsion could significantly enhance or enable some future robotic deep space science mission

9、s. This paper provides an overview of recent US high-power electric thruster research programs, describing the operating principles, challenges, and status of each technology. Mission analysis is presented that compares the benefits and performance of each thruster type for high priority NASA missio

10、ns. The status of space nuclear power systems for high-power electric propulsion is presented. The paper concludes with a discussion of power and thruster development strategies for future radioisotope electric propulsion systems.Article OutlineNomenclature1. Introduction2. Electric propulsion funda

11、mentals 2.1. EP figures of merit2.2. Categories of electric propulsion 2.2.1. Electrothermal thrusters2.2.2. Electrostatic thrusters2.2.3. Electromagnetic thrusters2.2.4. Advanced thruster concepts3. Nuclear electric propulsion systems 3.1. NEP component technologies 3.1.1. Reactor3.1.2. Power conve

12、rsion3.1.3. Heat rejection3.1.4. Power management and distribution4. Recent advances in high-power electric propulsion 4.1. Ion thruster technology development for the Jupiter Icy Moons Orbiter project 4.1.1. JIMO technology challenges for ion propulsion4.1.2. JIMO ion thruster development4.1.3. Hig

13、h voltage propellant isolators and insulators4.1.4. Ion engine life modeling and testing4.1.5. Radiation hardened materials and components4.1.6. Gridded ion power processing units4.1.7. Propellant management4.2. Very high Isp thruster with anode layer (VHITAL) 4.2.1. Systems engineering advantages4.

14、2.2. VHITAL two-stage technology4.2.3. VHITAL technology assessment and status4.3. Advanced lithium-fed applied-field Lorentz force accelerator (ALFA2) 4.3.1. Advantages of lithium-fed MPD thrusters4.3.2. ALFA2 thruster design4.3.3. Lithium vaporizor and feed system4.3.4. ALFA2 vehicle study4.4. Nuc

15、lear electric pulsed inductive thruster (NuPIT) 4.4.1. NuPIT experimental development4.4.2. NuPIT mission analysis4.4.3. NuPIT numerical modeling5. Nuclear electric propulsion missions analysis6. Status of nuclear space power systems7. Radioisotope electric propulsion 7.1. REP power systems 7.1.1. D

16、irect drive EP7.2. REP mission benefits8. Concluding remarksAcknowledgementsReferencesPurchase$ 37.95938Simulation of n-qubit quantum systems. II. Separability and entanglementOriginal Research ArticleComputer Physics Communications, Volume 175, Issue 2, 15 July 2006, Pages 145-166T. Radtke, S. Frit

17、zscheClose preview| Related articles|Related reference work articles AbstractAbstract | Figures/TablesFigures/Tables | ReferencesReferences AbstractStudies on the entanglement of n-qubit quantum systems have attracted a lot of interest during recent years. Despite the central role of entanglement in

18、 quantum information theory, however, there are still a number of open problems in the theoretical characterization of entangled systems that make symbolic and numerical simulation on n-qubit quantum registers indispensable for present-day research. To facilitate the investigation of the separabilit

19、y and entanglement properties of n-qubit quantum registers, here we present a revised version of the Feynman program in the framework of the computer algebra system Maple. In addition to all previous capabilities of this Maple code for defining and manipulating quantum registers, the program now pro

20、vides various tools which are necessary for the qualitative and quantitative analysis of entanglement in n-qubit quantum registers. A simple access, in particular, is given to several algebraic separability criteria as well as a number of entanglement measures and related quantities. As in the previ

21、ous version, symbolic and numeric computations are equally supported. Program summaryTitle of program:Feynman Catalogue identifier:ADWE_v2_0 Program summary URL: http:/cpc.cs.qub.ac.uk/summaries/ADWE_v2_0 Program obtainable from: CPC Program Library, Queens University of Belfast, N. Ireland Licensin

22、g provisions:None Computers for which the program is designed: All computers with a license of the computer algebra system Maple Maple is a registered trademark of Waterloo Maple Inc. Operating systems under which the program has been tested: Linux, MS Windows XP Programming language used:Maple 10 T

23、ypical time and memory requirements:Most commands acting on quantum registers with five or less qubits take 10 seconds of processor time (on a Pentium 4 with 2GHz or equivalent) and 520 MB of memory. However, storage and time requirements critically depend on the number of qubits, n, in the quantum

24、registers due to the exponential increase of the associated Hilbert space. No. of lines in distributed program, including test data, etc.:3107 No. of bytes in distributed program, including test data, etc.:13859 Distribution format:tar.gz Reasons for new version:The first program version established

25、 the data structures and commands which are needed to build and manipulate quantum registers. Since the (evolution of) entanglement is a central aspect in quantum information processing the current version adds the capability to analyze separability and entanglement of quantum registers by implement

26、ing algebraic separability criteria and entanglement measures and related quantities. Does this version supersede the previous version: Yes Nature of the physical problem: Entanglement has been identified as an essential resource in virtually all aspects of quantum information theory. Therefore, the

27、 detection and quantification of entanglement is a necessary prerequisite for many applications, such as quantum computation, communications or quantum cryptography. Up to the present, however, the multipartite entanglement of n-qubit systems has remained largely unexplored owing to the exponential

28、growth of complexity with the number of qubits involved. Method of solution: Using the computer algebra system Maple, a set of procedures has been developed which supports the definition and manipulation of n-qubit quantum registers and quantum logic gates T. Radtke, S. Fritzsche, Comput. Phys. Comm

29、. 173 (2005) 91. The provided hierarchy of commands can be used interactively in order to simulate the behavior of n-qubit quantum systems (by applying a number of unitary or non-unitary operations) and to analyze their separability and entanglement properties. Restrictions onto the complexity of th

30、e problem: The present version of the program facilitates the setup and the manipulation of quantum registers by means of (predefined) quantum logic gates; it now also provides the tools for performing a symbolic and/or numeric analysis of the entanglement for the quantum states of such registers. O

31、wing to the rapid increase in the computational complexity of multi-qubit systems, however, the time and memory requirements often grow rapidly, especially for symbolic computations. This increase of complexity limits the application of the program to about 6 or 7 qubits on a standard single process

32、or (Pentium 4 with 2GHz or equivalent) machine with 1GB of memory. Unusual features of the program: The Feynman program has been designed within the framework of Maple for interactive (symbolic or numerical) simulations on n-qubit quantum registers with no other restriction than given by the memory and processor resources of the computer. Whenever possible, both representations of quantum regis