Search results for "DWI"
showing 10 items of 529 documents
A Geometry-Based Underwater Acoustic Channel Model Allowing for Sloped Ocean Bottom Conditions
2017
This paper proposes a new geometry-based channel model for shallow-water ocean environments, in which the ocean bottom can slope gently down/up. The need for developing such an underwater acoustic (UWA) channel model is driven by the fact that the standard assumption of a flat ocean bottom does not hold in many realistic scenarios. Starting from a geometrical model, we develop a stochastic channel model for wideband single-input single-output vehicle-to-vehicle UWA channels using the ray theory assuming smooth ocean surface and bottom. We investigate the effect of the ocean-bottom slope angle on the distribution of the channel envelope, instantaneous channel capacity, temporal autocorrelati…
A Nonisovelocity Geometry-Based Underwater Acoustic Channel Model
2018
This paper proposes a new geometry-based shallow underwater acoustic (UWA) channel model allowing for nonisovelocity ocean conditions. The fact that the isovelocity assumption does not hold in many real-world scenarios motivates the need for developing channel models for nonisovelocity UWA propagation environments. Starting from a geometrical model, we develop a stochastic channel model for a single-input single-output (SISO) vehicle-to-vehicle UWA channel assuming that the ocean surface and bottom are rough and that the speed of sound varies with depth. The effect of the nonisovelocity condition has been assessed regarding its influence on the temporal autocorrelation function, the frequen…
Efficient Parallel Sort on AVX-512-Based Multi-Core and Many-Core Architectures
2019
Sorting kernels are a fundamental part of numerous applications. The performance of sorting implementations is usually limited by a variety of factors such as computing power, memory bandwidth, and branch mispredictions. In this paper we propose an efficient hybrid sorting method which takes advantage of wide vector registers and the high bandwidth memory of modern AVX-512-based multi-core and many-core processors. Our approach employs a combination of vectorized bitonic sorting and load-balanced multi-threaded merging. Thread-level and data-level parallelism are used to exploit both compute power and memory bandwidth. Our single-threaded implementation is ~30x faster than qsort in the C st…
Neighbor-list-free molecular dynamics on sunway TaihuLight supercomputer
2020
Molecular dynamics (MD) simulations are playing an increasingly important role in many research areas. Pair-wise potentials are widely used in MD simulations of bio-molecules, polymers, and nano-scale materials. Due to a low compute-to-memory-access ratio, their calculation is often bounded by memory transfer speeds. Sunway TaihuLight is one of the fastest supercomputers featuring a custom SW26010 many-core processor. Since the SW26010 has some critical limitations regarding main memory bandwidth and scratchpad memory size, it is considered as a good platform to investigate the optimization of pair-wise potentials especially in terms of data reusage. MD algorithms often use a neighbor-list …
Combining congested-flow isolation and injection throttling in HPC interconnection networks
2011
Existing congestion control mechanisms in interconnects can be divided into two general approaches. One is to throttle traffic injection at the sources that contribute to congestion, and the other is to isolate the congested traffic in specially designated resources. These two approaches have different, but non-overlapping weaknesses. In this paper we present in detail a method that combines injection throttling and congested-flow isolation. Through simulation studies we first demonstrate the respective flaws of the injection throttling and of flow isolation. Thereafter we show that our combined method extracts the best of both approaches in the sense that it gives fast reaction to congesti…
Rough Set Theory for Optimization of Packet Management Mechanism in IP Routers
2020
Bandwidth and consequently optimum overall efficiency of network system relies greatly on mechanism of packet management in IP routers. Our research objective is to implement rough set theory to minimizing number of the network system attributes responsible for decision making in selection of those packets, which improve its transmission. Such an approach is called priority queuing system model, as we assign priority to the packets selected, following rough set theory. Regardless of the file format, for all the routers, packets are transmitted in sequence one-by-one. Nonetheless, quality of streaming data largely depends on how much the packet loss is minimized, or eliminated at all, if pos…
Iron-loaded transferrin (Tf) is detrimental whereas iron-free Tf confers protection against brain ischemia by modifying blood Tf saturation and subse…
2018
Despite transferrin being the main circulating carrier of iron in body fluids, and iron overload conditions being known to worsen stroke outcome through reactive oxygen species (ROS)-induced damage, the contribution of blood transferrin saturation (TSAT) to stroke brain damage is unknown. The objective of this study was to obtain evidence on whether TSAT determines the impact of experimental ischemic stroke on brain damage and whether iron-free transferrin (apotransferrin, ATf)-induced reduction of TSAT is neuroprotective. We found that experimental ischemic stroke promoted an early extravasation of circulating iron-loaded transferrin (holotransferrin, HTf) to the ischemic brain parenchyma.…
Racial discourse in James Baldwin's Blues for Mister Charlie (1964) : drama and the hegemonic struggle
2012
[Rezension zu:] Gaier, Martin: Heinrich Ludwig und die »ästhetischen Ketzer«. Kunstpolitik, Kulturkritik und Wissenschaftsverständnis bei den Deutsch…
2015
Review of Martin Gaier's monograph about the German-Roman painter and art writer Heinrich Ludwig (1829-1897)