Hydrodynamic effects on flow through screens at intakes

The effect of fish protective screens placed at an angle less than 90° to the flow was investigated. The effect of the approach velocity, wire area and the screen angle were considered. Mathematical equations were developed for determining the pressure drop coefficient and the angle of the flow downstream from the screen. It was found that these parameters depend primarily on the variables considered and on the drag coefficient. This finding is important for design considerations of intakes with this type of fish screen arrangement.     

The burden of injuries in the Philippines: implications for national research policy

Injuries cause 10% of the mortality and 15% of disability worldwide. However, there is a paucity of data on injuries in the developing world where two-thirds of all injury deaths occur. This is the first published report characterizing the overall problem of injuries in the Philippines, a developing country in southeast Asia. This report defines the burden of injuries in the Philippines and identifies priority areas for the national health research agenda. A systematic review of 35 years of published and unpublished data on injuries in the Philippines (1960–1995) was conducted. Injury fatality rates increased by 196% from 14.3 per 100,000 in 1960 to 42.3 per 100,000 in 1995, and one in 11 deaths in the Philippines are due to injuries. Intentional injuries account for 48% of all injury deaths and motor vehicle crashes for 15%. For 15–44 year old males, injuries account for 42% of all deaths, 67% of which are intentional. The proportion of all deaths attributable to intentional injuries has increased by 925% and that of motor vehicle crashes by 600% from 1960 to 1995. Improvements in injury surveillance and documentation of non-fatal injury outcomes are needed. Research into risk factors and potential interventions for the prevention of intentional injuries should be a priority in the Philippines.     

Reports of the DAS02 working groups

This document is a collection of four working group reports in the areas of digital libraries, document image retrieval, layout analysis, and Web document analysis. These reports were the outcome of discussions by participants at the Fifth IAPR International Workshop on Document Analysis Systems held in Princeton, NJ on 19-21 August 2002.Published online: 16 March 2004     

SIVA: A System for Coverage-Directed State Space Search

We introduce SImulation Verification with Augmentation (SIVA), a tool for coverage-directed state space search on digital hardware designs. SIVA tightly integrates simulation with symbolic techniques for efficient state space search. Specifically, the core algorithm uses a combination of ATPG and BDDs to generate directed input vectors, i.e., inputs which cover behavior not excited by simulation. We also present approaches to automatically generate lighthouses that guide the search towards hard-to-reach coverage goals. Experiments demonstrate that our approach is capable of achieving significantly greater coverage than either simulation or symbolic techniques in isolation.     

Positioning of Base Stations in Wireless Sensor Networks

Wireless sensor networks (WSN) have attracted much attention in recent years due to their potential use in many applications such as border protection and combat field surveillance. Given the criticality of such applications, maintaining a dependable operation of the network is a fundamental objective. However, the resource-constrained nature of sensor nodes and the ad hoc formation of the network, often coupled with an unattended deployment, pose non-conventional challenges and motivate the need for special techniques for dependable design and management of WSN. In this article, we highlight the potential of careful positioning of the base station (BS), which acts as a sink node for the collected data, as a viable means for increasing the dependability of WSN. We categorize published work on optimal positioning of BS in WSN. Referring to such work as static positioning, we further introduce dynamic schemes that reposition the BS during the network operation. We show that dynamic BS positioning can be very effective in optimizing the network functional and non-functional performance objectives and in coping with dynamic changes in the environment and available network resources     

Cumulant-based inverse filters for blind deconvolution

Blind deconvolution of linear time-invariant (LTI) systems has received wide attention in various fields such as data communication and image processing. Blind deconvolution is concerned with the estimation of a desired input signal from a given set of measurements. This paper presents a technique for reconstructing the desired input from only the available corrupted data. The estimator is given in terms of an autoregressive moving average (ARMA) innovation model. This technique is based on higher order statistics (HOS) of a non-Gaussian output sequence in the presence of additive Gaussian or non-Gaussian noise. The algorithm solves a set of overdetermined linear equations using third-order cumulants of the given non-Gaussian measurements in the presence of additive Gaussian or non-Gaussian noise. The inverse filter is a finite impulse response (FIR) filter. Simulation results are provided to show the effectiveness of this method and compare it with a recently developed algorithm based on maximizing the magnitude of the kurtosis of estimate of the input excitation.     

Graft copolymerization of poly(methyl methacrylate) with some alkyl methacrylates by atom transfer radical polymerization method and thermal properties

The preparation of graft copolymers of poly(methyl methacrylate) with some alkyl methacrylates were carried out via atom transfer radical polymerization method catalyzed by CuCl/2,2′-bipyridine and using a macroinitiator, poly[(methyl methacrylate)-co-(3,5-bis(chloroacetoxy)phenyl methacrylate)], including an amount of 1 mol % having α-halogeno carbonyl group in the side groups. Although the number-average molecular weights of a graft copolymer series of n-butyl methacrylate (n-ButMA) ended at different times increased from 55,700 to 99,500, the polydispersities decreased from 1.85 to 1.39 with time. The thermal degradation kinetics of macroinitiator and a two-armed graft copolymer of n-ButMA with this macroinitiator, PMMA-g-PnButMA: 4% (by mol), were carried out at different heating rates by thermogravimetric analysis and the results were compared. Using both the Flynn–Wall–Ozawa and Kissinger methods, the decomposition activation energies for macroinitiator were determined as 168 and 162 kJ/mol, respectively; they were also calculated as 233 and 239 kJ/mol for PMMA-g-PnButMA: 4%. The solid state thermodegradation mechanisms of both macroinitiator and PMMA-g-PnButMA: 4% are R₁-type mechanism, a phase boundary-controlled reaction, and F₁-type mechanism, a random nucleation with one nucleus on the individual particle, respectively. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Experimental Study of an Adding Interferometer at Millimeter Waves

In order to study an original detection architecture for future cosmology experiments based on wide band adding interferometry, we have tested a single baseline bench instrument based on commercial components. The instrument has been characterized in the laboratory with a wide band power detection setup. A method which allows us to reconstruct the complete transfer function of the interferometer has been developed and validated with measurements. This scheme is useful to propagate the spurious effects of each component till the output of the detector.     

Recovery from multiple simultaneous failures in wireless sensor networks using minimum Steiner tree

In some applications, wireless sensor networks (WSNs) operate in very harsh environments and nodes become subject to increased risk of damage. Sometimes a WSN suffers from the simultaneous failure of multiple sensors and gets partitioned into disjoint segments. Restoring network connectivity in such a case is crucial in order to avoid negative effects on the application. Given that WSNs often operate unattended in remote areas, the recovery should be autonomous. This paper promotes an effective strategy for restoring the connectivity among these segments by populating the least number of relay nodes. Finding the optimal count and position of relay nodes is NP-hard and heuristics are thus pursued. We propose a Distributed algorithm for Optimized Relay node placement using Minimum Steiner tree (DORMS). Since in autonomously operating WSNs it is infeasible to perform a network-wide analysis to diagnose where segments are located, DORMS moves relay nodes from each segment toward the center of the deployment area. As soon as those relays become in range of each other, the partitioned segments resume operation. DORMS further model such initial inter-segment topology as Steiner tree in order to minimize the count of required relays. Disengaged relays can return to their respective segments to resume their pre-failure duties. We analyze DORMS mathematically and explain the beneficial aspects of the resulting topology with respect to connectivity, and traffic balance. The performance of DORMS is validated through extensive simulation experiments.     

Introducing two landscape components from Turkey: Irim and Kesik

A very particular set of landscape components, namely the irim and the kesik, found in the peri-urban rural area called Karabaglar, are considered. This area is in the contiguous land of the city of Mugla, in southwestern Turkey, and is administered by its municipality. It has a rural character, yet also includes summerhouses for the inhabitants of the city. Physical resemblance of the irim and the kesik to the hedgerow suggests similar functions, but a closer look reveals that they have a wider range of features and aspects. Functioning not only as a marker of agricultural land sub-divisions, they also play an important role in the hydrology of the area. While their specific traditional features can be used in designed landscapes, the intention here is, first, to introduce the irim, the kesik and the very special setting offered by Karabaglar, which are now under the pressure of urban encroachment. A comparison with the hedgerow is nevertheless useful in order to better understand related aspects and features.