Recently, there has been an interest in making electronic cash protocols more practical for electronic commerce by developing e-cash which is divisible (e.g., a coin which can be spent incrementally but total purchases are limited to the monetary value of the coin). In Crypto`95, T. Okamoto presented the first practical divisible, untraceable, off-line e-cash scheme, which requires only O(log N) computations for each of the withdrawal, payment and deposit procedures, where N = (total coin value)/(smallest divisible unit). However, Okamoto`s set-up procedure is quite inefficient (on the order of 4,000 multi-exponentiations and depending on the size of the RSA modulus). The authors formalize the notion of range-bounded commitment, originally used in Okamoto`s account establishment protocol, and present a very efficient instantiation which allows one to construct the first truly efficient divisible e-cash system. The scheme only requires the equivalent of one (1) exponentiation for set-up, less than 2 exponentiations for withdrawal and around 20 for payment, while the size of the coin remains about 300 Bytes. Hence, the withdrawal protocol is 3 orders of magnitude faster than Okamoto`s, while the rest of the system remains equally efficient, allowing for implementation in smart-cards. Similar to Okamoto`s, the scheme is based on …

We consider a Two Higgs Doublet Model with Flavor Changing Scalar Neutral Currents arising at the tree level. All the most important constraints are taken into account and the compatibility with the present Electroweak measurements is examined. The Flavor Changing couplings involving the third family are not constrained to be very small and this allows us to predict some interesting signals of new physics.

This report describes the system designed and fabricated for the National Center for Advanced Information Component Manufacturing (NCAICM) project number 9322-135. The system is a device capable of simultaneously aligning two glass plates and sealing them together with glass frit. The process development was divided into two phases. The first was thermal sealing in an ambient environment. The second was sealing a controlled environment in a vacuum.

The Imaging and Detection Program (IDP) within Laser Programs at Lawrence Livermore National Laboratory (LLNL) in cooperation with the Hughes Aircraft Company has developed a versatile, high performance, airborne experimental test-bed (AETB) capability. The test-bed has been developed for a wide range of research and development experimental applications including radar and radiometry plus, with additional aircraft modifications, optical systems. The airborne test-bed capability has been developed within a Douglas EA-3B Skywarrior jet aircraft provided and flown by Hughes Aircraft Company. The current test-bed payload consists of an X-band radar system, a high-speed data acquisition, and a real-time processing capability. The medium power radar system is configured to operate in a high resolution, synthetic aperture radar (SAR) mode and is highly configurable in terms of waveforrns, PRF, bandwidth, etc. Antennas are mounted on a 2-axis gimbal in the belly radome of the aircraft which provides pointing and stabilization. Aircraft position and antenna attitude are derived from a dedicated navigational system and provided to the real-time SAR image processor for instant image reconstruction and analysis. This paper presents a further description of the test-bed and payload subsystems plus preliminary results of SAR imagery.

It is argued that the principles of classical physics are inimical to the development of an adequate science of consciousness. The problem is that insofar as the classical principles are valid consciousness can have no effect on the behavior, and hence on the survival prospects, of the organisms in which it inheres. Thus within the classical framework it is not possible to explain in natural terms the development of consciousness to the high-level form found in human beings. In quantum theory, on the other hand, consciousness can be dynamically efficacious: quantum theory does allow consciousness to influence behavior, and thence to evolve in accordance with the principles of natural selection. However, this evolutionary requirement places important constraints upon the details of the formulation of the quantum dynamical principles.

The Hanford Site was founded in early 1943 for the top secret government mission of producing plutonium for the world`s first atomic weapons. A great deal of land was needed, both to separate various Site facilities from each other, and to provide buffer zones for safety and security purposes. In total, 640 square miles were occupied by the original Hanford Site and its buffer zones. Much of this land had been earmarked for inclusion in the Columbia Basin Irrigation Project (CBP). After World War II ended, a series of national decisions led to a long-term mission for the Hanford Site, and area residents learned that the Site lands they had hoped to farm would be withheld from agricultural production for the foreseeable future. A long set of negotiations commenced between the federal management agency responsible for Hanford (the Atomic Energy Commission -- AEC), and the Bureau of Reclamation (BOR), Department of the Interior that managed the CBP. Some lands were turned back to agriculture, and other compromises made, in the Site`s far northern buffer lands known as the Wahluke Slope, during the 1950s. In the mid-1960s, further negotiations were about to allow farming on lands just north of the Columbia …

This demonstration project uses modern simulation techniques to illustrate the important technologies and design variables that an auto-designer would consider in production a high efficiency, low emissions vehicle. Simulation and modeling techniques use the idea of capturing the relationships between real components of the systems with mathematical equations. These equations are then solved on a computer to simulate the behavior or performance of the system under various conditions. In the current demonstration project, we focus on many variations of a hydrogen-powered vehicle.

The evolution of the scrape-off layer (SOL) during a disruption in the DIII-D tokamak is modeled using the 2-D UEDGE transport code. The focus is on the thermal quench phase when most of the energy content of the discharge is rapidly transported across the magnetic separatrix where it then flows to material surfaces or is radiated. Comparisons between the simulation and an experiment on the DIII-D tokamak are made with the heat flux to the divertor plate, and temperature and density profiles at the SOL midplane. The temporal response of the separate electron and ion heat-flux components to the divertor plate is calculated. The sensitivity of the solution to assumptions of electron heat-flux models and impurity radiation is investigated.

In a 2 X 2 TeV {mu}{sup +}{mu}{sup -} Collider almost 15 MW of power is deposited in the machine and detector components due to the unavoidable {mu}{r_arrow}{ital e{nu}{nu}{anti {nu}}} decays. The resulting heat load to the cryogenic systems and the background levels in the collider detectors significantly exceed those in any existing or designed hadron and {ital e}{sup +}{ital e}{sup -} colliders. This paper shows that by carefully designing the final focus system, by embedding shielding and by taking other protective measures the heat load and backgrounds can be mitigated by several orders of magnitude.

The TBNLC collider design uses Relativistic Klystron Two-Beam Accelerator (RK-TBA) units as the rf power source for a NLC-type linac at 11.4 GHz. In this paper we report on a simple analysis using RK-TBA units as a rf power source for a CLIC-type linac at 30 GHz. The desired rf macropulse duration is less than 50 ns with a repetition rate of 600 Hz. We propose to use magnetic pulse compression units driving ferrite core induction cells for this system. Many elements of the TBNLC remain the same for a collider design at this higher frequency.

With its portability, ease to add built-in functions and objects in C, and fast array facility among many other features, Python proved to be an excellent language for creating programmable scientific applications. In addition to the two modules presented, there are also other progresses at LLNL in using Python. For example, Python interfaces are being developed for at least three graphics packages, and Python interpreter and applications have been built on distributed platforms such as meiko and Cray T3D.

We present results of molecular dynamics simulation studies of Cu segregation to the {Sigma}11{l_angle}1{bar 1}0{r_angle}/(113)(113) grain boundary (GB) in Al. Simulations were performed with EAM potentials for Al and Al-Cu. Results predict that Cu atoms tend to order along either side of the interface even in the pure symmetrical tilt boundary, forming alternating chains along the {l_angle}{bar 3}{bar 3}2{r_angle} direction. Nucleation of the chains is driven by a change in the local atomic level stress induced by the pre-existing Cu atoms at the GB.

A prototype rf power source based on the Relativistic Klystron Two- Beam Accelerator (RK-TBA) concept is being constructed at LBNL to study physics, engineering, and costing issues. The prototype, called RTA, is described and compared to a full scale design appropriate for driving the Next Linear Collider. Specific details of the induction core test and pulsed power system are presented. Details of the 1-MeV, 1.2-kA induction gun currently under construction are described.

Consider mapping a regular i x j quadrilateral mesh of a rectangle onto a surface. The quality of the mapped mesh of the surface depends heavily on which vertices of the surface correspond to corners of the rectangle. The authors problem is, given an n-sided surface, chose as corners four vertices such that the surface resembles a rectangle with corners at those vertices. Note that n could be quite large, and the length and width of the rectangle, i and j, are not prespecified. In general, there is either a goal number or a prescribed number of mesh edges for each bounding curve of the surface. The goals affect the quality of the mesh, and the prescribed edges may make finding a feasible set of corners difficult. The algorithm need only work for surfaces that are roughly rectangular, particular those without large reflex angles, as otherwise an unstructured meshing algorithm is used instead. The authors report on the theory and implementation of algorithms for this problem. They also given an overview of a solution to a related problem called interval assignment: given a complex of surfaces sharing curves, globally assign the number of mesh edges or intervals for each curve …

This paper presents an overview of an approach to address complexity issues and real-life problems in large, urban transportation systems. In this context we discuss the fundamental problem of designing a metropolitan transportation system which is both efficient and controllable.