Spark (mathematics)

About: Spark (mathematics) is a research topic. Over the lifetime, 7304 publications have been published within this topic receiving 63322 citations.

SparkCL: A Unified Programming Framework for Accelerators on Heterogeneous Clusters

Abstract: We introduce SparkCL, an open source unified programming framework based on Java, OpenCL and the Apache Spark framework. The motivation behind this work is to bring unconventional compute cores such as FPGAs/GPUs/APUs/DSPs and future core types into mainstream programming use. The framework allows equal treatment of different computing devices under the Spark framework and introduces the ability to offload computations to acceleration devices. The new framework is seamlessly integrated into the standard Spark framework via a Java-OpenCL device programming layer which is based on Aparapi and a Spark programming layer that includes new kernel function types and modified Spark transformations and actions. The framework allows a single code base to target any type of compute core that supports OpenCL and easy integration of new core types into a Spark cluster.

Waste-spark engine ignition

Abstract: A distributorless ignition system is provided which includes an ignition coil for firing a pair of first and second spark plugs at the same time. The ignition system includes a changeover switch which, when assuming one operating position, causes the first spark plug to produce negative polarity spark and the second spark plug to produce positive polarity spark and, when assuming another operating position, causes the first spark plug to produce positive polarity spark and the second spark plug to produce negative polarity spark. The operating position of changeover switch is changed every time the number of sparks produced by each of the first and second spark plugs becomes two. By this, the number of negative polarity sparks and the number of positive polarity sparks produced by each of the first and second spark plugs on compression stroke at its corresponding cylinder over a long period of time are the same. This enables the center electrode and ground electrode of each of the first and second spark plugs to wear away equally. An ignition method is also provided.

Local fuel concentration, ignition and combustion in a stratified charge spark combustion in a stratified charge spark ignited direct injection engine: Spectroscopic, imaging and pressure-based measurements

Abstract: A recently developed spark emission spec-troscopy technique has been used to measure the effects of fuel injection timing, spark timing and intake swirl level on the individual-cycle fuel concentration at the spark gap in a wall-guided spark ignited direct injection (SIDI) engine The fuel-concentration measurements were made simultaneously with measurements of individual-cycle spark discharge energy and cylinder pressure Endoscopic imaging of the fuel spray and high-speed imaging of combustion (both broadband and spectrally resolved) augment these quantitative data For optimum engine operation, the fuel-air equivalence ratio at the spark gap just after spark breakdown is rich on average (〈φ〉 ≈14–15) and varies widely from cycle to cycle (∼25 per cent) The evolution with crank angle of the mean equivalence ratio and its cycle-to-cycle fluctuations are correlated with the cylinder pressure, heat release and imaging data to provide insights into fuel transport and mixture preparation that are i