Power-aware localized routing in wireless networks

A cost aware metric for wireless networks based on remaining battery power at nodes was proposed for shortest-cost routing algorithms, assuming constant transmission power. Power-aware metrics, where transmission power depends on distance between nodes and corresponding shortest power algorithms were also proposed. We define a power-cost metric based on the combination of both node's lifetime and distance-based power metrics. We investigate some properties of power adjusted transmissions and show that, if additional nodes can be placed at desired locations between two nodes at distance d, the transmission power can be made linear in d as opposed to d^α dependence for α ⩾ 2. This provides basis for power, cost, and power-cost localized routing algorithms where nodes make routing decisions solely on the basis, of location of their neighbors and destination. The power-aware routing algorithm attempts to minimize the total power needed to route a message between a source and a destination. The cost-aware routing algorithm is aimed at extending the battery's worst-case lifetime at each node. The combined power-cost localized routing algorithm attempts to minimize the total power needed and to avoid nodes with a short battery's remaining lifetime. We prove that the proposed localized power, cost, and power-cost efficient routing algorithms are loop-free and show their efficiency by experiments     

STRIP - a strip-based neural-network growth algorithm for learningmultiple-valued functions

We consider the problem of synthesizing multiple-valued logic functions by neural networks. A genetic algorithm (GA) which finds the longest strip in V subset, dbl equalsK(n) is described. A strip contains points located between two parallel hyperplanes. Repeated application of GA partitions the space V into certain number of strips, each of them corresponding to a hidden unit. We construct two neural networks based on these hidden units and show that they correctly compute the given but arbitrary multiple-valued function. Preliminary experimental results are presented and discussed.     

Parallel structured milling machines with long X travel

The paper presents research and development results of one parallel structured milling machine with long X travel. The developed milling machine experimental prototype is based on a newly developed 3-DOF spatial parallel mechanism. In comparison with similar developed machines, it has several advantages such as: rather regular shape of the workspace similar to serial machines, greater stiffness by nature of strut arrangement and good force and speed ratio through the entire machine's workspace.     

Power and cost aware localized routing with guaranteed delivery in unit graph based ad hoc networks

In a localized routing algorithm, each node currently holding a message makes forwarding decision solely based on the position information about itself, its neighbors and destination. In a unit graph, two nodes can communicate if and only if the distance between them is no more than the transmission radius, which is the same for each node. This paper proposes localized routing algorithms, aimed at minimizing total power for routing a message or maximizing the total number of routing tasks that a network can perform before a partition. The algorithms are combinations of known greedy power and/or cost aware localized routing algorithms and an algorithm that guarantees delivery. A shortcut procedure is introduced in later algorithm to enhance its performance. Another improvement is to restrict the routing to nodes in a dominating set. These improvements require two‐hop knowledge at each node. The efficiency of proposed algorithms is verified experimentally by comparing their power savings, and the number of routing tasks a network can perform before a node loses all its energy, with the corresponding shortest weighted path algorithms and localized algorithms that use fixed transmission power at each node. Significant energy savings are obtained, and feasibility of applying power and cost‐aware localized schemes is demonstrated. Copyright © 2004 John Wiley & Sons, Ltd.     

Nitroxyl Delivered by Angeli’s Salt Causes Short-Lasting Activation Followed by Long-Lasting Deactivation of Meningeal Afferents in Models of Headache Generation

The role of TRPA1 receptor channels in meningeal nociception underlying the generation of headaches is still unclear. Activating as well as inhibitory effects of TRPA1 agonists have been reported in animal models of headache. The aim of the present study was to clarify the effect of the TRPA1 agonist nitroxyl (HNO) delivered by Angeli’s salt in two rodent models of meningeal nociception. Single fibre recordings were performed using half-skull preparations of mice (C57BL/6) in vitro. Angeli’s salt solution (AS, 300 µM) caused short-lasting vigorous increases in neuronal activity of primary meningeal afferents, followed by deactivation and desensitisation. These effects were similar in TRPA1 knockout and even more pronounced in TRPA1/TRPV1 double-knockout mice in comparison to wild-type mice. The activity of spinal trigeminal neurons with afferent input from the dura mater was recorded in vivo in anesthetised rats. AS (300 µM) or the TRPA1 agonist acrolein (100 and 300 µM) was applied to the exposed dura mater. AS caused no significant changes in spontaneous activity, while the mechanically evoked activity was reduced after acrolein application. These results do not confirm the assumption that activation of trigeminal TRPA1 receptor channels triggers the generation of headaches or contributes to its aggravation. Instead, there is evidence that TRPA1 activation may have an inhibitory function in the nociceptive trigeminal system.     

A comparative numerical study between dissipative particle dynamics and smoothed particle hydrodynamics when applied to simple unsteady flows in microfluidics

Laminar flows through channels, pipes and between two coaxial cylinders are of significant practical interest because they often appear in a wide range of industrial, environmental, and biological processes. Discrete particle modeling has increasingly been used in recent years and in this study we examined two of these methods: dissipative particle dynamics (DPD) and smoothed particle hydrodynamics (SPH) method when applied to (a) time-dependent, plane Poiseuille flow and (b) flow between two coaxial cylinders at low Reynolds numbers. The two examples presented in this paper give insight into different features of the two discrete particle methods. It was found that both methods give results with high accuracy, but CPU time is much larger (of order 10²–10³ in the second example) for DPD than for SPH model. This difference is due to the fact that the number of time steps for the DPD model is much greater than for the SPH model (since thermal fluctuations are taken into account in the DPD model).     

Comparative Investigation of the Volatile Urinary Profiles in Different <Emphasis Type="Italic">Phodopus</Emphasis> Hamster Species

Stir bar sorptive extraction method was used for investigation of the urinary volatile profiles in male and female Phodopus campbelli and Phodopus sungorus hamsters. Additionally, female Phodopus roborowsky urinary profiles were characterized. A quantitative analytical approach allowed comparisons of 17 selected compounds in urine. Results showed that campbelli and sungorus species show similar urinary volatile profiles for males and females. Differences appeared only in concentrations. Several unique compounds, such as pyrazine derivatives, were found to be gender- and age-specific. P. roborowsky females exhibited a completely different urinary volatile profile from campbelli and sungorus females, featuring a unique set of substituted quinoxalines.     

大型铸件用的Crl3Ni4——-6Mo钢的韧性评定

对于用4—6％Ni变质的低碳马氏体铬钢在动力设备大型铸件方面的发展和应用的一些基本问题，近来已做了一系列的研究。有关最佳成分（包括不希望有的元素的极限含量在内）的主要原则，事实上已得到阐明，同时，机械性能所要求的预想组织的热处理方法，也已得到验证。