Showing papers on "Spark (mathematics) published in 2004"

The SPARK Agent Framework

Abstract: There is a need for agent systems that can scale to real-world applications, yet retain the clean semantic underpinning of more formal agent frameworks. We describe the SRI Procedural Agent Realization Kit (SPARK), a new BDI agent framework that combines these two qualities. In contrast to most practical agent frameworks, SPARK has a clear, well-defined formal semantics that is intended to support reasoning techniques such as procedure validation, automated synthesis, and procedure repair. SPARK also provides a variety of capabilities such as introspection and meta-level reasoning to enable more sophisticated methods for agent control, and advisability techniques that support user directability. On the practical side, SPARK has several design constructs that support the development of large-scale agent applications. SPARK is currently being used as the agent infrastructure for a personal assistant system for a manager in an office environment.

Using global code motions to improve the quality of results for high-level synthesis - eScholarship

Abstract: The quality of synthesis results for most, high-level synthesis approaches is strongly affected by the choice of control flow (through conditions and loops) in the input description. This leads to a need for high-level and compiler transformations that overcome the effects of programming style on the quality of generated circuits. To address this issue, we have developed a set of speculative code-motion transformations that enable movement of operations through, beyond, and into conditionals with the objective of maximizing performance. We have implemented these code transformations, along with supporting code-motion techniques and variable renaming techniques, in a high-level synthesis research framework called Spark. Spark takes a behavioral description in ANSI-C as input and generates synthesizable register-transfer level VHDL. We present results for experiments on designs derived from three real-life multimedia and image processing applications, namely, the MPEG-1 and -2 and GNU image manipulation program applications. We rind that the speculative-code motions lead to reductions between 36% and 59% in the number of states in the finite-state machine (controller complexity) and the cycles on the longest path (performance) compared with the case when only nonspeculative code motions are employed. Also, logic synthesis results show fairly constant critical path lengths (clock period) and a marginal increase in area.

Spark – A Generic Simulator for Physical Multi-agent Simulations

Abstract: In this paper we describe a new multi-agent simulation system, called Spark, for physical agents in three-dimensional environments. Our goal in creating Spark was to provide a great amount of flexibility for creating new types of agents and simulations. To achieve this, we implemented a flexible application framework and exhausted the idea of replaceable components in the resulting system. In comparison to specialized simulators, users can effortlessly create new simulations by using a scene description language. Spark is a powerful and flexible tool to state different multi-agent research questions. It is used as official simulator for the first three-dimensional RoboCup Simulation League competition. We present the concepts we used to achieve the flexibility in our system and show how we seamlessly integrated the different subsystems into one user-friendly framework.

Fuel injector spark plug

Abstract: A spark plug and fuel injector combination. The spark plug has a central channel that funnels fuel into the lower portion of the spark plug, where it is superheated. A solenoid system causes a needle valve to rise up to allow a measured quantity of fuel to be injected into a cylinder through a nozzle, where it vaporizes upon exiting the spark plug. A spring releases the needle valve to close the nozzle. The spark plug also has an ignition ring on the base. The ignition ring produces an encompassing spark, which produces complete combustion of the vaporized fuel. This produces more power and better fuel economy.

Nonperiodic oscillations of pressure in a spark ignition combustion engine

Abstract: We report our results on nonperiodic experimental time series of pressure in a spark ignition engine. The experiments were performed for a low rotational velocity of a crankshaft and a relatively large spark advance angle. We show that the combustion process has many chaotic features. Surprisingly, the reconstructed attractor has a characteristic butterfly shape similar to a chaotic attractor of Lorentz type. The suitable recurrence plot shows that the dynamics of the combustion is a nonlinear multidimensional process mediated by stochastic noise.

New spark-test device for material characterization

Abstract: An automated spark test system based on combining field emission and spark measurements, exploiting a discharging capacitor is investigated. In particular, the remaining charge on the capacitor is analytically solved assuming the field emitted current to follow the Fowler Nordheim expression. The latter allows for field emission measurements from pA to A currents, and spark detection by complete discharge of the capacitor. The measurement theory and experiments on Cu and W are discussed.

Development of parallel spark electrical discharge machining

Abstract: This paper describes the development of parallel spark EDM method. In the discharge circuit, the electrode is divided into multiple electrodes, each of which is electrically insulated and connected to the pulse generator through a diode. A capacitor is inserted parallel to each discharge gap between each electrode and workpiece (here workpiece is common for each electrode). Compared with conventional EDM in which only a singular discharge can be generated for each pulse, multiple discharges can dispersively be generated for each pulse in parallel spark EDM. Results of experiments on parallel spark EDM and conventional EDM show that not only is the machining process more stable, but the machining speed and surface roughness can also be improved with parallel spark EDM.

Printed circuit board (PCB) with spark path for overvoltage protection between two electrically conductive regions on PCB, especially caused by electrostatic discharge (ESD), for electronic modules

Abstract: On second conductive region (2) is formed second spark tip in direction of first region (1). Between first region spark tip (11) and second spark tip remains gap (d2) which is greater than gap (d0) between each spark tip and opposite rim of opposite region.Preferably both regions, including spark tips, are structured by etching. PCB may be coated by non-conductive protective layer in section adjacent to spark tip and opposite rim, while spark path proper is without any protective layer.

Powertrain control module spark duration diagnostic system

Abstract: A system and method for diagnosing ignition system performance of an internal combustion engine. The method operates an engine control unit to produce a sequence of spark ignition current pulses through primary windings of a plurality of ignition coils. The current pulses produce voltage pulses across electrodes of the spark plugs. The voltage pulses produce flyback voltages across the primary windings. Output pulses are produced in response to the flyback voltages having time durations related to the time durations of the sparks produced by the spark plugs. Digital signal are produced in response to each one of the output pulses representative of the spark time duration of a corresponding one of the sparks. A comparison of the digital signals determines whether the spark time duration of one of the spark plugs is substantially different from the spark time durations of the other ones of the plurality of spark plugs.

Integral spark detector in fitting which supports igniter in gas turbine engine

Abstract: A system for detecting spark in an igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is positioned adjacent the igniter, to detect current pulses in the igniter, to thereby infer the presence of spark. The pick-up can take the form of a coil embedded in a mounting bracket which is used to fasten the igniter to the engine.

Misfire, Knock and NOx Mapping of a Laser Spark Ignited Single Cylinder Lean Burn Natural Gas Engine

Abstract: Evermore demanding market and legislative pressures require stationary lean burn natural gas engines to operate at higher efficiencies and reduced levels of emissions. Higher in-cylinder pressures and leaner air/fuel ratios are required in order to meet these demands. The performance and durability of spark plug ignition systems suffer as a result of the increase in spark energy required to maintain suitable engine operation under these conditions. Advancing the state of the art of ignition systems for these engines is critical to meeting increased performance requirements. Laser-spark ignition has shown potential to improve engine performance and ignition system durability to levels required meet or exceed projected requirements. This paper discusses testing which extends previous efforts [1] to include constant fueling knock, misfire, thermal efficiency, and NO x emissions mapping of a single cylinder lean burn natural gas engine. Tests are conducted using an open beam path laser spark ignition system and a conventional spark plug based system for contrast. Under the conditions tested, the laser-spark ignition system increased the total operating envelope of the engine by 46% when compared to the conventional ignition system. Due to a wider misfire margin using the laser spark system, NO x emissions were half the minimum value of the spark plug ignition system with no appreciable degradation in thermal efficiency. Hydrocarbon emissions were comparable for both systems. The results of the testing are discussed in detail.

Capabilities of surface composition analysis using a long laser-induced breakdown spectroscopy spark.

Abstract: An apparatus has been investigated based on laser-induced breakdown spectroscopy (LIBS) for the rapid determination of the spatial distribution of elements on surfaces. Cylindrical optics are used to create a linear spark approximately 1 cm in length. Light emitted by atoms excited along the spark is collected and provides a spatial profile of elemental composition in the sample when analyzed with a spectrometer and gated charge-coupled device (ICCD) detector. Moving the spark across the sample surface as spectral data is recorded at regularly spaced intervals allows for the development of a three-dimensional elemental distribution map (emission intensity versus spatial distribution across an area). An analysis of the spatial resolution of this methodology is presented along with representative data from several sample types. Application of full-image analysis allowing for simultaneous investigations into the spatial distributions of multiple elements is also discussed and results are presented.

A Parallelizing Approach to the High-Level Synthesis of Digital Circuits

Abstract: SPARK: A Parallelizing High – Level Synthesis of Digital Circuits presents a novel approach to the high-level synthesis of digital circuits – that of parallelizing high-level synthesis (PHLS). This approach uses aggressive code parallelizing and code motion techniques to discover circuit optimization opportunities beyond what is possible with traditional high-level synthesis. This PHLS approach addresses the problems of the poor quality of synthesis results and the lack of controllability over the transformations applied during the high-level synthesis of system descriptions with complex control flows, that is, with nested conditionals and loops.

Laser Spark Ignition: Laser Development and Engine Testing

Abstract: Evermore demanding market and legislative pressures require stationary lean-burn natural gas engines to operate at higher efficiencies and reduced levels of emissions. Higher in-cylinder pressures and leaner air/fuel ratios are required in order to meet these demands. Contemporary ignition systems, more specifically spark plug performance and durability, suffer as a result of the increase in spark energy required to maintain suitable engine operation under these conditions. This paper presents a discussion of the need for an improved ignition source for advanced stationary natural gas engines and introduces laser spark ignition as a potential solution to that need. Recent laser spark ignition engine testing with natural gas fuel including NOx mapping is discussed. A prototype laser system in constructed and tested and the results are discussed and solutions provided for improving the laser system output pulse energy and pulse characteristics.Copyright © 2004 by ASME

A Simulation-Based Testing and Training Environment for Building Controls

Abstract: A hybrid simulation environment for controls testing and training is described. A real-time simulation of a building and HVAC system is coupled to a real building control system using a hardware interface. A prototype has been constructed and tested in which the dynamic performance of both the HVAC equipment and the building envelope is simulated using SPARK (Simulation Problem Analysis and Research Kernel). A low cost hardware interface between the simulation and the real control system is implemented using plug-in analog-todigital and digital-to-analog cards in a personal computer. The design and implementation of the hardware interface in SPARK are described. The development of a variant of this environment that uses a derivative of EnergyPlus to test the implementation of a natural ventilation control strategy in real control hardware is also described. Various applications of the hybrid simulation environment are briefly described, including the development of control algorithms and strategies, control system product testing and the pre-commissioning of building control system installations. The application to the education and training of building operators and HVAC service technicians is discussed in more detail, including the development of a community college curriculum that includes the use of the hybrid simulation environment to teach both control system configuration and HVAC troubleshooting.

Modeling and compensation of the fuel path dynamics of a spark ignited engine

Abstract: In the last decade, the technical evolution of the combustion engines has reached an high level of growth. This evolution was surely triggered by the increasing restrictions for the emission levels imposed by the governments. The direct consequence of this improvement is an increase in the complexity of the engine management systems, which means an increase of algorithms that have to be parameterized. To cope with this complexity, the current parametrization methods have to be refined. For instance, the implementation of parametrical models based on physical principles can reduce dramatically the time spent on the test-bench to calibrate a specific engine. This thesis is focused on the modeling of the fuel path dynamics, from the injection of the fuel into the intake manifold up to the measurement of the air/fuel ratio in the exhaust, for a Port Fuel Injected engine (PFI engine). The main dynamics which are present in the fuel path are the wall wetting dynamics and the exhaust gas dynamics. They represent the storage and evaporation of fuel in the intake manifold, and the mixing of the fuel vapor in the cylinder and in the exhaust. On one hand, the goal is to obtain a model with a simple structure (control-oriented modeling) and based on few tunable parameters, so that it can be implemented easily in a standard engine management system. On the other hand, the obtained model has to cover the whole operating

Method of informing pilot of aircraft of spark detected in gas turbine engine

Abstract: A system for detecting spark in an igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is positioned adjacent the igniter, to detect current pulses in the igniter, to thereby infer the presence of spark. A detection system detects the spark, and informs the pilot of the aircraft of the detected spark. Thus, if the pilot encounters a problem in starting the engine, the pilot can rapidly determine whether the igniter is involved in the problem.

High energy primary spark ignition system for a gas turbine engine

Abstract: An exciter circuit for a gas turbine engine delivers a first single high-energy spark followed by subsequent sparks of relatively lower energy to ensures start reliability by specifically clearing ice build-up at the ignition plugs.

Passive high-temperature amplifier for amplifying spark signals detected in igniter in gas turbine engine

Abstract: A system for detecting spark in an igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is positioned adjacent the igniter, to detect current pulses in the igniter, to thereby infer the presence of spark. The signal produced is small, and requires amplification. However, the environment is hot, often exceeding 400 degrees F. The invention utilizes an amplifier composed of passive components, in the form of an RLC circuit.

Automatic knock control system

Abstract: A fuzzy control system for the knock of a gasoline engine was proposed. The comparison of different spark advances and timing setting effects was used to determine knock intensity. In the light of the adaptive spark timing control function, proper engine response is attained, and different spark advances governed by the fuzzy control system under different states are compared and tested. Experiment verifies that the function of spark timing on air-fuel ratio is improved to a great extent when spark advance angle is controlled to make the engine work in trace knock intensity. The new technique is used to overcome the knock problem in automotive engines and its effectiveness is shown.

Metal in-situ analyzer

Abstract: A metallic original position analyzer comprising an exciting light source system, a spectrum system, a single time spark discharge signal high speed acquisition system, a signal analyzing system for digital interpreting of the spark spectrum single time discharging, and a sample moving / positioning system for continued excitation synchronous scanning. The invention uses sample synchronous scanning for realizing continuous sample movement and uninterrupted spark discharge, it can simultaneously perform the analysis of sample chemical composition, distribution of element, porosity and inclusion distribution with accurate and comprehensive results.

Characterizing Engine Emissions with Spark Efficiency Curves

Abstract: Emissions optimization, particularly for complex engines, relies on developing mathematical correlations or 'Response Surface Models' of engine outputs. There is a clear tradeoff between the complexity of the model and its usefulness for a range of optimization tasks. Several current Sl engine management systems use a 'Spark efficiency curve' to elegantly describe the response of engine torque to spark advance using a prescribed characteristic line that is fitted to a spark sweep with only two degrees of freedom. This provides a powerful method of data reduction. A similar technique has been developed to characterize engine emissions data. A single efficiency curve with only two degrees of freedom can be used to accurately describe the response of, say, hydrocarbon emissions to spark over a wide range of engines and operating conditions. The technique offers similar data reduction advantages for engine management system developers and those optimizing engines using high DoF models. The form and application of the efficiency curves is discussed and examples of application to tasks such as engine emission optimization are discussed.

Sensor for detection of spark in igniter in gas turbine engine

Abstract: An igniter for a gas turbine engine. An igniter generates a plasma, or spark, somewhat similar to an automotive spark plug. In the invention, an inductive pick-up is used to detect current which produces the spark, the thereby infer the presence of spark. Further, the sensor is located directly adjacent the igniter, in a hot environment, often exceeding 400 F.

Higher-performance spark plug and ramrod engine ignition system using piezo-electric enhancement components

Abstract: This invention constitutes improvements and innovates with novel preferred embodiments the use of a new spark plug casting mold and process—using either wax or recycled plastic resins for more flexibly casting the bulk of this novel spark plug design and its corresponding now unique method of manufacture. A utility invention and design for providing new improved spark plug(s) and engine ignition components configured in a new manner and for/and as an internal combustion engine ignition system(s); that specifically are also unique and novel in both design configuration(s), some operation(s), method(s) of manufacture and product(s) assembly; plus also novel and original in the specific chemistry of some metal alloy formulas; and the componentization(s) of some of this/these new combined spark plug/ignition system configuration(s) with unique and novel piezo-electric components. This/these invention(s) also constitutes improvements and innovates with novel preferred embodiments the use of a new spark plug casting mold and process-using either wax or recycled plastic resins for more flexibly casting the bulk of this novel spark plug design and its corresponding now unique method of manufacture. The objects and advantages of new comprehensive design and unique manufacturing configuration processes will also incorporate and demonstrate an improved satisfactory spark plug and engine ignition system electrode(s) which can be efficiently manufactured and can be accomplished by fuse-weld connection continuity/welding of a wire around the center electrode. Which in a variant of this novel patent design configuration will result in improvements in the electron flow or spark to emanate or to “ramrod” “shoot-out” like a “shooting star or rocket” in comparison to all conventional and all prior spark plug designs, configurations and engine ignition system performance and operation(s). Thus, both an improved spark plug and ignition system performance is/are provided.

Ignition spark enhancing device

Abstract: An ignition spark enhancing device and spark plug wire disposed in or establishing the electrical path between a spark source and a spark plug of an internal combustion engine. The device includes one or more coils of conductive hollow tubing formed from a length of conductive tubing configured for connection to the spark plug wire of the device or to a spark plug. The tubing is preferably copper and may also be aluminum or other conductive material and is also preferably used to form each spark plug wire as well for durability. At least five complete loops or turns wound concentrically or in helix fashion are preferred. The device is also preferably coated with a non-conductive material to reduce any risk of electrical shock or short circuit.

Electric spark plug

Abstract: An electric spark plug is used for igniting fuel in a cylinder of a gasoline engine. Preferably, the electric spark plug is electrically discharged on a sphere-to-sphere electrical discharge basis, in which leading ends of a central electrode (10) and a ground electrode (11) which are installed in an electric spark plug body (1) are spherically shaped electrodes (10a, 11a). Accordingly, a concentrative spark discharge occurs due to an electrical path breakdown between the two spherical electrodes (10a, 11a) without a partial discharge. As a result, the spark flames become strong, to thereby burn fuel in the cylinder quickly and increase power of the engine. Also, the electrodes are not nearly worn, to thereby raise no discharge voltage increase and discharge time delay. Also, a replacement period of spark plugs becomes remarkably long. The spark plug has not nearly suffered from the circumstances in the cylinder.

Controlling spark for an engine with controllable valves

Abstract: A system and method to control spark in a cylinder of a multi-cylinder engine. Spark can be controlled in a cylinder while reducing the possibility of producing a spark at a spark plug coupled to an ignition coil.