The ef®ciencies of methods employed in solution of building simulation models are considered and compared by means of benchmark testing. Direct comparisons between the Simulation Problem Analysis and Research Kernel (SPARK) and the HVACSIM‡ programs are presented, as are results for SPARK versus conventional and sparse matrix methods. An indirect comparison between SPARK and the IDA program is ...

Most points-to analysis research has been done on different systems by different groups, making it difficult to compare results, and to understand interactions between individual factors each group studied. Furthermore, points-to analysis for Java has been studied much less thoroughly than for C, and the tradeoffs appear very different. We introduce SPARK, a flexible framework for experimenting...

J.M. Lehr, C.E. Baum, W.D. Prather and F.J. Agee High Energy Sources Division, Phillips Laboratory Kirtland AFB, New Mexico 87117 The Air Force is interested in compact ultra-wideband systems which utilize a minimum volume of high pressure gas. These desires lead us to look closely at single channel spark gaps, because both the size and volume of gas, for example, hydrogen, under pressure can b...

Spark-assisted homogeneous charge compression ignition (HCCI) combustion may be a method to improve the operation of HCCI engines. In the current study, the impact of spark assist on the fundamental properties of ignition and combustion was investigated in a single cylinder, optically-accessible research engine. Early port fuel injection and air preheating were used with indolene fuel in the st...

Apache Spark is an execution engine that besides working as an isolated distributed, in-memory computing engine also offers close integration with Hadoop’s distributed file system (HDFS). Apache Spark's underlying appeal is in providing a unified framework to create sophisticated applications involving workloads. It unifies multiple workloads, handles unstructured data very well and has easy-to...

Apache Spark is an open-source cluster computing framework. It has emerged as the next generation big data processing engine, overtaking Hadoop MapReduce which helped ignite the big data revolution. Spark maintains MapReduce’s linear scalability and fault tolerance, but extends it in a few important ways: it is much faster (100 times faster for certain applications), much easier to program in d...

Upon activation, mammalian eggs release billions of zinc ions in an exocytotic event termed the "zinc spark." The zinc spark is dependent on and occurs coordinately with intracellular calcium transients, which are tightly associated with embryonic development. Thus, we hypothesized that the zinc spark represents an early extracellular physicochemical marker of the developmental potential of the...

Simulations of forced ignition of non-premixed laminar counterflow flames are used to study the effect of strain rate on ignition success. A one dimensional calculation is performed, using detailed methane chemical kinetics and treating the spark as an instantaneous heat release in an inert mixing layer. Ignition success depends on the mixture composition at the spark location, resulting in lea...

AIMS The cardiac ryanodine receptor (RyR) Ca(2+) release channel homotetramer harbours approximately 21 potentially redox-sensitive cysteine residues on each subunit and may act as a sensor for reactive oxygen species (ROS), linking ROS homeostasis to the regulation of Ca(2+) signalling. In cardiac myocytes, arrayed RyRs or Ca(2+) release units are packed in the close proximity of mitochondria,...

This work presents an application of the optimal control theory to find trade offs between fuel consumption and pollutant emissions (CO, HC, NOx) sustaining hybrid vehicles. Both cold start normal operations are considered. The problem formulation includes two state variables: battery energy catalyst temperature; three torque repartition engine motor, spark advance, equivalence ratio. Optimal r...