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It has been reported that Internet Protocol (IP) packet traffic exhibits self‐similarity or long range dependence (LRD) and causes the degradation of switch performance. Therefore, it is crucial for an appropriate buffer design of a switch. In this paper, we investigate delay behavior of the switch under self‐similar variable length packet traffic by modeling it as MMPP/M/1/K queueing system wherein MMPP (Markov‐Modulated Poisson Process) is fitted by equating the variance of MMPP and that of self‐similar traffic. MMPP model is already validated one to emulate the self‐similar characteristics. Voids that will occur because of variability in packet length is considered. We investigate mean delay against system parameters, traffic parameters and fitting parameters. Numerical results show that analysis presented in this paper is useful in dimensioning the switch.

In this paper we review cosmic ray effects on the performance and reliability of microelectronic systems and human health as well as the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in ground-based, atmospheric flight, and space flight environments. Ground based test methods applied to microelectronic components and systems are used in combination with radiation transport and reaction codes to predict the performance of microelectronic systems in their operating environments. Similar radiation transport codes are an important tool for evaluating possible human health effects of cosmic ray. Finally, the limitations on human space operations beyond low-Earth orbit imposed by long term exposure to galactic cosmic rays are discussed.

Numerical models serve an important role in eddy current non-destructive evaluation applications. The results of computational models provide meaningful insight into the underlying physics, help theoretically visualize the field/sample interaction and help optimize sensor design and assist algorithms developing for interpreting the measured signals. However, three dimensional computational models can be time consuming. This paper presents a fast and efficient GPU based numerical model for simulating eddy current testing techniques. The model, based on boundary integral method, uses novel matrix compression techniques to optimize the solver performance on GPU architectures. Validation results of model predictions for a number of sample geometries are presented.

This paper presents an automatic segmentation method for delineation of the clinically significant contours of the equine larynx from an endoscopic image. These contours are used to diagnose the most common disease of horse larynx laryngeal hemiplegia. In this study, hierarchal structured contour map is obtained by the state-of-the-art segmentation algorithm, gPb-OWT-UCM. The conic-shaped outer boundary of equine larynx is extracted based on Pascal's theorem. Lastly, Hough Transformation method is applied to detect lines related to the edges of vocal folds. The experimental results show that the proposed approach has better performance in extracting the targeted contours of equine larynx than the results of using only the gPb-OWT-UCM method.

The trend of decreasing device size and increasing chip densities involving several hundred millions of transistors per chip has resulted in tremendous increase in design complexity. Low power SRAMs are essential in today's demand as they are preferred as on chip memories with read write stability. This paper presents a method based on multi-Vt to increase read, write stability and reduce the total leakage power dissipation of SRAMs while maintaining their performance. The proposed method is based on the observation that read and write delays of a memory cell in an SRAM block depend on the physical distance of the cell from the sense amplifier and it is also depend on Vt.

There is growing interest in memristive devices following their recent nanoscale fabrication. This paper describes initial consideration of the implementation of artificial intelligence within predominantly memristive hardware. In particular, versions of Alan Turing’s discrete dynamical network formalism — the unorganised machine — are used as the knowledge representation scheme and a population-based search technique is used to design appropriate networks. Issues including memristor count and global network synchrony are compared for two memristive logic implementations (NAND and IMP) on a well-known simulated robotics benchmark task. It is shown that IMP networks are harder to design than NAND, but are simpler to implement and require fewer processor cycles.

Search Engine gives an ordered list of web search results in response to a user query, wherein the important pages are usually displayed at the top with less important ones afterwards. It may be possible that the user may have to look for many screen results to get the required documents. In literatures, many page ranking algorithms has been given to find the page rank of a page. For example PageRank is considered in this work. This algorithm treats all the links equally when distributing rank scores. That's why this algorithm some time gives equal importance to all the pages. But in real this can not be happen because, if two pages have same rank then how we can judge which page is more important then other. So this paper proposes another idea to organize the search results and describe which page is more important when confliction of same rank is produced by the PageRank. So that the user can get more relevant and important results easily and in a short span of time.

The Wireless network can be employed to connect wired network to the wireless network. Wireless local area networks (WLAN) are more bandwidth limited as compared to the wired networks because they rely on an inexpensive, but error prone, physical medium (air). Hence it is important to evaluate their performance. This paper presents a study of IEEE 802.11b wireless LAN (WLAN). The performance evaluation has been presented via a series of test with different parameters such as data rate, different number of nodes and physical characteristics. The different qualities of service parameter are chosen to be throughput, media access delay and dropped data packets. The simulation results show that an IEEE 802.11b WLAN can support up to 60 clients with modest throughput. Finally the results are compared to evaluate the performance of wireless local networks.

In this paper we present a concept for an Intelligent System for Radiogram Analysis (ISAR) for welds quality inspection. Both, hardware and software solutions have been introduced in the system. The software operates with variety of scanner standards. It contains preliminary image processing (linear and nonlinear filtering algorithms) and some specialized functions, like Sauvola’s tresholding or IQI detection. The aim of the ISAR system is to support a radiologist in his work.

A newly developed three‐dimensional direct simulation Monte Carlo (DSMC) simulation package, named GRASP (“Generalized Rarefied gAs Simulation Package”), is reported in this paper. This package utilizes the concept of simulation engine, many C++ features and software design patterns. The package has an open architecture which can benefit further development and maintenance of the code. In order to reduce the engineering time for three‐dimensional models, a hybrid grid scheme, combined with a flexible data structure compiled by C++ language, are implemented in this package. This scheme utilizes a local data structure based on the computational cell to achieve high performance on workstation processors. This data structure allows the DSMC algorithm to be very efficiently parallelized with domain decomposition and it provides much flexibility in terms of grid types. This package can utilize traditional structured, unstructured or hybrid grids within the framework of a single code to model arbitrarily complex...

This paper proposes a VLSI circuit implementing a low power, high‐resolution spiking neural network (SNN) with STDP synapses, inspired by mammalian olfactory systems. By representing mitral cell action potential by a step function, the power consumption and the chip area can be reduced. By cooperating sub‐threshold oscillation and inhibition, the network outputs can be distinct. This circuit was fabricated using the TSMC 0.18 μm 1P6M CMOS process. Post‐layout simulation results are reported.

Resistive switching memory (also known as RRAM for resistive random access memory) is considered a promising candidate for the next‐generation nonvolatile memories. This paper summarizes the electrical characterization methodologies for RRAM performance evaluation and the investigation of resistive switching mechanisms. Some unique issues in RRAM measurements are discussed, including polarity, forming, and switching control. Product‐oriented RRAM characterization needs to consider yield, failure mechanisms, and reliability issues, which has only began to be addressed by the RRAM research community.

Fermi National Accelerator Laboratory is constructing a superconducting 1.3 GHz cryomodule test facility located at the New Muon Lab building. The facility will be used for testing and validating cryomodule designs as well as support systems. For the initial phase of the project, a single Type III plus 1.3 GHz cryomodule will be cooled and tested using a single Tevatron style standalone refrigerator. Subsequent phases involve testing as many as two full RF units consisting of up to six 1.3 GHz cryomodules with the addition of a new cryogenic plant. The cryogenic infrastructure consists of the refrigerator system, cryogenic distribution system as well as an ambient temperature pumping system to achieve 2 K operations with supporting purification systems. A discussion of the available capacity for the various phases versus the proposed heat loads is included as well as commissioning results and testing schedule. This paper describes the plans, status and challenges of this initial phase of the New Muon Lab cryogenic system., 8 pp. Cryogenic Engineering Conference and International Cryogenic Materials Conference 28 Jun - 2 Jul 2009. Tucson, Arizona

In this paper, a health monitoring problem for the electrical network of more electric aircraft is addressed. To undertake the health monitoring task, the multi‐model detection technique is applied. Multi‐model based approach associates to each health status a corresponding linear time invariant model which is derived by adjusting appropriately the non‐faulty system model to a particular fault situation. The original health monitoring problem can be therefore formulated as a model detection problem. Besides the introduction of the theoretical preliminary of multi‐model based approach, the computer‐aided design process, right‐sized modelling and realtime simulation based validation for residual generator with Dymola and Matlab are also discussed. Health monitoring for an input filter of an DC motor drive serves as an application case to illustrate the proposed scheme. The designed residual generators are validated on the original nonlinear system with time‐domain simulation.

In this paper, we present an implementation of Advanced Encryption Standard (AES) cryptographic algorithm using state‐of‐the‐art Virtex‐5 Field Programmable Gate Array (FPGA). The design is coded in Very High Speed Integrated Circuit Hardware Description Language (VHDL). Timing simulation is performed to verify the functionality of the designed circuit. Performance evaluation is also done in terms of throughput and area. The design implemented on Virtex‐5 (XC5VLX50FFG676‐3) FPGA achieves a maximum throughput of 4.34 Gbps utilizing a total of 399 slices.

Digital holographic systems are a class of two step, opto‐numerical, three‐dimensional imaging techniques which permit nanometric resolution of in‐vivo objects. The linear canonical transform (LCT) describes the paraxial propagation of a scalar wave field through any system comprising of lenses and free space. There are a great many different recording architectures used in holography. The interaction of these with the limitations of the recording device is poorly understood. Use of the LCT as a propagation model provides a unified description of the optical systems, facilitating direct comparison. We demonstrate how to use phase space diagrams to compare different digital holographic recording set‐ups, analyze the effects of the digital camera, and compare the sampling requirements of different numerical reconstruction algorithms. The results presented in this paper will allow digital holography practitioners to select an optical system to maximize the quality of their reconstructed image using a priori knowledge of the camera and object.

In this paper we illustrate the features and study the applicability of transactional memory ™ as an efficient and easy‐to‐use alternative for handling memory conflicts in multi‐theaded physics simulations that use shared memory. The tool used for our preliminary analysis of this novel construct is IBM’s freely available Software Transactional Memory (STM) system. Instead of attempting to apply it to a production grade simulation code, we developed a much simpler test code that exhibits most of the salient features of modern unstructured mesh algorithms, but without the complicated physical models. We apply STM to two frequently used algorithms in realistic multi‐physics codes. Our computational experiments indicate a good fit between these application scenarios and the TM features.

In this paper, we provide the performance analysis of fiber‐optic CDMA system using the Perfect Difference Codes. We have designed the FO‐CDMA system & by changing the various parameter of the system, analyze the performance of perfect difference codes in term of BER. The main parameters of the system which can affect the performance are data rate, number of users & length of fiber optics. As the data rate increased from 1 Gbps to 5 Gbps, the BER increases from 1.02×10−34 to 1.17×10−17 for a single user at 30 m Km. Similarly as the length of fiber increases BER again increases & quality factor decreases.

The Solid State Devices (SSD) which are increasingly being adopted in today’s data storage Systems, have higher capacity and performance but lower reliability, which leads to more frequent rebuilds and to a higher risk. Although SSD is very energy efficient compared to Hard Disk Drives but Bit Error Rate (BER) of an SSD require expensive erase operations between successive writes. Parity based RAID (for Example RAID4,5,6)provides data integrity using parity information and supports losing of any one (RAID4, 5)or two drives(RAID6), but the parity blocks are updated more often than the data blocks due to random access pattern so SSD devices holding more parity receive more writes and consequently age faster. To address this problem, in this paper we propose a Model based System of hybrid disk array architecture in which we plan to use RAID 4(Stripping with Parity) technique and SSD drives as Data drives while any fastest Hard disk drives of same capacity can be used as dedicated parity drives. By this propo...

This paper proposes the LQ‐Servo controller for AQM (Active Queue Management) routers. The proposed controller structure is made by taking a traditional servo mechanism based on Linear Quadratic approach and by augmenting a new state variable to the feed forward loop. Since the controller structure is consists of a standard optimal feedback regulator and a feed forward controller, it is able to enhance the usefulness of resources and to reduce unnecessary memory reservations such as RAM (Random Access Memory) or SMA (Shared Memory Area) on ordinary router systems, respectively.

This investigation involves the combination of support vector machines (SVM) and k‐means clustering implemented on radar signal. SVM classifier based on k‐means algorithm has an advance for classifying unlabeled data. To classify the vehicle types automatically, the combined method is implemented with radar signals. This paper proposed a classifier training algorithm based on SVM and k‐means clustering as follows (i) using the k‐means algorithm to label the input feature data extracted from radar signal into two subsets, (ii) train SVM with labeled data, and (iii) classify unidentified radar signal into large vehicle or small vehicle with the trained classifier. Training features of radar signal includes (i) signal volume and (ii) sum of signal variations, both in frequency domain. These features are taken as system input, while vehicle types as system output. The proposed algorithm is implemented and demonstrated with real FMCW radar signals. With the numerical experiment, satisfying result is obtained.

In this paper we present a low‐cost 3D tracking system which we have developed and tested in order to move away from traditional 2D interaction techniques (keyboard and mouse) in an attempt to improve user’s experience while using a CVE. Such a tracking system is used to implement 3D interaction techniques that augment user experience, promote user’s sense of transportation in the virtual world as well as user’s awareness of their partners. The tracking system is a passive optical tracking system using stereoscopy a technique allowing the reconstruction of three‐dimensional information from a couple of images. We have currently deployed our 3D tracking system on a collaborative research platform for investigating 3D interaction techniques in CVEs.

This paper proposes a Web Service for the digital photogrammetry softcopy workstation based on Service Oriented Web Architecture. The integration of the web service with the capability of the digital photogrammetry workstation results in distributed programming sharing and processing of remotely sensed digital images. In the proposed approach, the data exchange and the service sharing are performed platform independently. The developed tools show the interoperability of the remotely coded photogrammetry applications on the remotely stored digital images in the field of digital photogrammetry.

This paper describes a new circuit that minimizes the number of operations needed to execute the Census transform on 256 grey‐level images. The proposed architecture is modular and easily scalable. It can elaborate images with different resolutions and allows regular slice‐based layouts to be achieved, thus ensuring also a low design complexity. When realized by using a XILINX VIRTEX4 XC4VLX15 device, the circuit proposed here occupies only 936 slices and reaches a running frequency of about 333 MHz.

In this paper, we analyze and compare four image‐based visual servoing control laws. Three of them are classical while a new one is proposed. This new control law is based on a behavior controller to adjust the movement of the camera. It can also be used to switch between the classical methods. An analytical study of all control schemes when translational motion along and rotational motion around the optical axis is also presented. Finally, simulation and experimental results show that the new control law with a behavior controller has a wider range of success than the other control schemes and can be used to avoid local minima and singularities.

The correction of the stereoscopic images is a task which consists in replacing acquired images by other images having the same properties but which are simpler to use in the other stages of stereovision. The use of the pre‐calculated tables, built during an off line calibration step, made it possible to carry out the off line stereoscopic images rectification. An improvement of the built tables made it possible to carry out the real time rectification.In this paper, we describe an improvement of the real time correction approach so it can be exploited for a possible implementation on an FPGA component. This improvement holds in account the real time aspect of the correction and the available resources that can offer the FPGA Type Stratix 1S40F780C5.

Over the years, medical imaging has become very common and data intensive. New technology is needed to help visualize and analyze these large, complex data sets, especially in an acute care situation where time is of the essence. Also it is very important to present the data in an efficient and simple manner to aid the clinical decision making processes. There is a need for a clinical workstation that handles data from different modalities and performs the necessary post‐ processing operations on the data in order to enhance the image quality and improve the reliability of diagnosis. This paper briefly explains clinical workstation, emphasizing the requirements and challenges in design and architecture for the development of such systems.

In this paper, a simulation‐based optimization method for the design of antenna pattern applied for mobile broadcasting and the 802.11a WLAN is presented. Based on genetic algorithm (GA), numerical simulation, and unified optimization framework, the optimization methodology is proposed for the antenna design automation. A Z‐shaped antenna is optimized with respect to the return loss by our method. Inspired by the scenario of GA for optical proximity correction in our earlier work, we firstly partition the edges of the antenna into segments, and then adjust the movements of each segment to construct the geometry of new antenna. The external simulator is then called to simulate and evaluate the performance of the new antenna. If the simulated results meet the specific constraints, we output the optimized antenna. Otherwise, the evolutionary algorithms will enable us to search solution again. Our preliminary results confirm the robustness and efficiency of the proposed simulation‐based optimization method.

Arc welding is a widely used technology in almost all sectors of industrial production. Many tasks are automatically performed by robots. This paper presents a flexible vision based quality management system to detect defects online during the weld process.

Super‐Resolution (SR) image reconstruction is the area of research and development which produces one or a set of high‐resolution (HR) images from one or a set of low‐resolution (LR) frames. Nowadays, there is a great number of methods of SR either for fixed or video sequence and for gray, color or hyperspectral images. There is, however, an area where we need still great effort is the 3D data, particularly in medical and biological or in non destructive testing (NDT) imaging systems where very often we may obtain low resolution 3D volumes reconstructed in different contexts (PET, Microscopy, molecular imaging, SAR imaging, holography and 3D TV, etc.) and we would like to reconstruct a HR 3D volume from a few LR ones. In this paper, first we report a few extensions to a recently developed Bayesian SR methods and then propose to extend it to 3D case.

Illumination artifacts systematically occur in 2D cross‐section confocal microscopy imaging . These bias can strongly corrupt an higher level image processing such as a segmentation, a fluorescence evaluation or even a pattern extraction/recognition. This paper presents a new fully automated bias correction methodology based on large image database preprocessing. This method is very appropriate to the High Content Screening (HCS), method dedicated to drugs discovery. Our method assumes that the amount of pictures available is large enough to allow a reliable statistical computation of an average bias image. A relevant segmentation evaluation protocol and experimental results validate our correction algorithm by outperforming object extraction on non corrupted images.

This paper analyzes how erroneous source impedance measurement due to residual errors within a VNA affect the four‐noise parameter determination based on the cold‐source noise measurement procedure and the eight‐term linear model. It shows that although the errors disturb the complex noise characterization of a CMOS transistor at RF, mismatch and finite bandwidth errors seem to be more significant.

Dynamic behavior of a helium liquefier has been studied in detail with a Cryogenic Process REal‐time SimulaTor (C‐PREST) at the National Institute for Fusion Science (NIFS). The C‐PREST is being developed to integrate large‐scale helium cryogenic plant design, operation and maintenance for optimum process establishment. As a first step of simulations of cooldown to 4.5 K with the helium liquefier model is conducted, which provides a plant‐process validation platform. The helium liquefier consists of seven heat exchangers, a liquid‐nitrogen (LN2) precooler, two expansion turbines and a liquid‐helium (LHe) reservoir. Process simulations are fulfilled with sequence programs, which were implemented with C‐PREST based on an existing liquefier operation. The interactions of a JT valve, a JT‐bypass valve and a reservoir‐return valve have been dynamically simulated. The paper discusses various aspects of refrigeration process simulation, including its difficulties such as a balance between complexity of the adopted models and CPU time.

Linear thermoacoustic theory is a powerful tool to understand the working mechanism of many regenerative machines. Based on the theory, the authors have developed a computer code “Thermoacoustic Simulator” for analyzing and designing different regenerative cryocoolers including String refrigerators, Stirling and G-M types of pulse tube refrigerators and G-M cryocoolers. Also, standing-wave and traveling-wave thermoacoustic machines can be simulated, too. This paper will present the philosophy of the “Thermoacoustic Simulator” and some demonstrations of simulation for different types of cryocoolers and thermoacoustic engines.

The Space Based Infrared System-Low (SBIRS-Low) segment is a near-term Air Force program for developing and deploying a constellation of low-earth orbiting observation satellites with gimbaled optics cooled to cryogenic temperatures. The optical system design and requirements present unique challenges that make conventional cooling approaches both complicated and risky. The Cryocooler Interface System (CIS) provides a remote, efficient, and interference-free means of cooling the SBIRS-Low optics. Technology Applications Inc. (TAI), through a two-phase Small Business Innovative Research (SBIR) program with Air Force Research Laboratory (AFRL), has taken the CIS from initial concept feasibility through the design, build, and test of a prototype system. This paper presents the development and demonstration testing of the prototype CIS. Prototype system testing has demonstrated the high efficiency of this cooling approach, making it an attractive option for SBIRS-Low and other sensitive optical and detector systems that require low-impact cryogenic cooling.

The Baikal program provides a superpower generator creation which uses a plasma opening switch for output pulse production. The MOL facility is being developed within the frames of this program to test main units and systems of the planned generator at 4–6 MV, 3 MA and 100 ns. The MOL facility is planned to use 7 parallel plasma opening switch modules placed in the relatively compact vacuum chamber of 140 cm diameter. This aims at solving two main technical issued: plasma opening switch module development with external applied magnetic field and plasma switch modules synchronization. The paper describes plasma switch module design and low inductance load synchronization experimental tests results.

A robust measurement of the clustering amplitude of the sub-mm population of starburst galaxies requires large-area surveys (≫1 deg2). The largest-format arrays subtend only 10 arcmin2 on the sky and hence scan-mapping is a necessary observing mode. Providing realistic representations of the extragalactic sky and atmosphere, as the input to a detailed simulator of the telescope and instrument performance, allows important decisions to made about the design of large-area fully-sampled surveys and observing strategies. In this paper we present preliminary simulations that include detector noise, time-constants and array geometry, telescope pointing errors, scan speeds and scanning angles, sky noise and sky rotation.

The existing Tevatron spool piece has been upgraded by adding a single-phase to two-phase heat exchanger or recooler. This will enhance the single-phase to two-phase heat transfer and, along with other upgrades, allow for a higher energy. The performance of the heat exchanger was predicted numerically using a multi-node finite difference model. The present paper reviews the design of the Tevatron spool recooler. The discussion includes: a technical description of a Tevatron spool; the heat exchanger mathematical model; design criteria and constraints; fabrication and assembly procedure; tests and performance analysis.

In this paper we propose to use the “Multi-Frequency Excitation and Spectrogram Method” (MFES) and dynamic neural network models to reconstruct flaws profiles in planar conducting specimens. Two kinds of neural models are proposed: a forward model, which could be utilized as a fast solver in an inversion iterative algorithm, and an inverse model, which enable us to directly obtain a flaw profile within a few hundreds milliseconds. Dynamic feed-forward networks (with moving window) were applied in both cases.

When designing a new microprocessor, it is important for computer architects to understand the impact of design decisions on performance. Average execution characteristics—such as cache hit rate, branch prediction accuracy, or average instruction-level parallelism—however, only provide poor insight into the interaction of computer programs and design options. We believe that considering distributions of workload characteristics will yield many more additional information for making optimal design decisions. In this paper, by measuring distributions we show that many characteristics are nonuniformly distributed over the entire execution of a computer program on modern microprocessors: the available instruction-level parallelism, the inter-instruction dependency distance, the degree-of-use of instruction output values, the intervals between cache misses, and the intervals between branch mispredictions. In addition, we explain where this nonuniformity comes from and what the implications are for the design o...

The new package NORTICA (Numerical ORbit Tracking In Cyclotrons with Analysis) of computer codes for beam dynamics simulations is under development at NSCL. The package was started as a replacement for the code MONSTER [1] developed in the laboratory in the past. The new codes are capable of beam dynamics simulations in both CCF (Coupled Cyclotron Facility) accelerators, the K500 and K1200 superconducting cyclotrons. The general purpose of this package is assisting in setting and tuning the cyclotrons taking into account the main field and extraction channel imperfections. The computer platform for the package is Alpha Station with UNIX operating system and X-Windows graphic interface. A multiple programming language approach was used in order to combine the reliability of the numerical algorithms developed over the long period of time in the laboratory and the friendliness of modern style user interface. This paper describes the capability and features of the codes in the present state.

This paper presents a new method based on the application of the Hough Transform for solving the robot motion problem and their intermediate steps: geometric modelling and collision detection. In terms of modelling, given a set of points, which is the representation of a given object, the maximum inner and the minimum outer spherically-extended polytopes (s-tope) are automatically generated. Collision detection is based on the computation of the translational penetration distance. Such a distance also allows to compute an intermediate point when collision avoidance is required. The set of intermediate points describes a solution to the path-planning problem. This new approach introduces an important decrease in the computational time required for robot motion planning.

In support of the international collaborative effort into fusion research, work has begun to re-commission the Deuterium Negative Ion Source Experiment (DENISE) at Dublin City University (DCU). Modifications to the original system are nearing completion. The major goal of these modifications is easier access to both the ion source and the extraction region for diagnostic systems. A new source chamber has been installed. It can be used with both standard Langmuir probes, and a new laser photo-detachment probe currently under construction. The source chamber allows operation in any one of three modes: filament driven, CW RF driven, or Pulsed RF driven (up to 3 kW of 13.5 MHz RF at 250 Hz). A PC computer control system based on LabView is nearing completion and is intended for both system control and data logging. An investigation into the production and extraction of H{sup -} ions has begun. Langmuir probe data has been collected at pressures from 5-200 mTorr, for CW RF powers between 25 and 600 W, and for 3 radial probe positions. This paper will present the current status of DENISE and the future plans for this versatile source.

This paper discusses the developments in the electron gun simulation programs that are based on EGUN with its derivatives and supporting programs. Much of the code development has been inspired by technology changes in computer hardware; the implications of this evolution on EGN2 are discussed. Some examples and a review of the capabilities of the EGUN family are described.

In this paper, we describe a user‐friendly systems‐engineering environment consisting of a special user‐interface paradigm that controls one of three hierarchical levels of data‐visualization. The user‐interface paradigm (1) embeds the User within the algorithms, (2) emphasizes equation simplicity, (3) encourages algorithm linking, and (4) provides to the User real‐time supplementary information, concerning the equations, higher‐level algorithms, their linkage, and Program Understanding and maintainability. We call this user‐interface paradigm IDEAs, short for Integrated Design Environment Algorithms, and the medium for its implementation is the spreadsheet. We are working to implement data visualization at one of three possible hierarchical levels that we refer to as low‐end, mid‐range, and high‐end. We give an example of our system‐engineering environment (using low‐end data visualization) that was used to characterize and optimize a complex systems‐engineering problem, namely, an advanced space‐propulsion system called the Mirror Fusion Propulsion System (MFPS). We also discuss mid‐range data visualization that consists of spreadsheet‐controlled objects in a computer‐aided‐design (CAD) environment. We finish with a discussion of implementing the high‐end data‐visualization level that consists of spreadsheet‐controlled objects in “Virtual Reality (VR).”

ARGUS is a three-dimensional, electromagnetic, particle-in-cell (PIC) simulation code that is being distributed to U.S. accelerator laboratories in collaboration between SAIC and the Los Alamos Accelerator Code Group. It uses a modular architecture that allows multiple physics modules to share common utilities for grid and structure input., memory management, disk I/O, and diagnostics, Physics modules are in place for electrostatic and electromagnetic field solutions., frequency-domain (eigenvalue) solutions, time- dependent PIC, and steady-state PIC simulations. All of the modules are implemented with a domain-decomposition architecture that allows large problems to be broken up into pieces that fit in core and that facilitates the adaptation of ARGUS for parallel processing ARGUS operates on either Cray or workstation platforms, and MOTIF-based user interface is available for X-windows terminals. Applications of ARGUS in accelerator physics and design are described in this paper.

The Galileo Science Data System (SDS) is designed to meet the data processing, data management, and data distribution requirements of the Galileo mission to Jupiter. The principal computing power of the Galileo SDS is provided by two VAX cluster systems, the Image Processing System (IPS) of the Multimission Image Processing Laboratory (MIPL), and the Science VAX Cluster (SVC). The SDS design provides support for a user base of approximately 300 scientists, centralized access to disk storage, interactive data visualization, high speed wide area network access, and support of both local and remote, standalone and clustered, computer systems with both Unix and VMS based operating systems. At the core of the SVC hybrid system is a dual host MicroVAX 4000. Peripheral to this central CPU system is a distributed network of VMS and Unix based workstations on a multi‐protocol local area network (LAN). The local and remote computer systems are connected to the NASA Science Internet (NSI) via a group of programmable routers which filter access on the basis of TCP/IP and DECnet addresses. In this paper we discuss details of the configuration and operational plans for the SDS at Jupiter.

This paper describes a system for performing histogramming of n‐tuple data at interactive rates using a commercial SIMD processor array connected to a work‐station running the well‐known Physics Analysis Workstation software (PAW). Results indicate that an order of magnitude performance improvement over current RISC technology is easily achievable.

This paper is essentially a verbatim record of the talk given at the end of the conference summarizing the topics discussed in the Architectures and Algorithms sessions.

This paper will present data on the latest ISR results on charm and beauty production, in an effort towards a more global synthesis of previous ISR data. The total charmed hadron cross‐section of 1 mb implied by these new results will be discussed. Expectations for new heavy flavor production at the CERN pp Collider will finally be discussed, based on what we have learned thus far at the ISR.