Minimizing the Handoff Latency in Ad-Hoc Networks When Streaming Media to Mobile Devices

The number of mobile devices connecting to networks independently of a fixed point of attachment is increasing. These wireless networks differ in bandwidth, size and location of the coverage area, access costs and network characteristics. Mobile multimedia devices such as PDA's, palmtops and laptops will also vary greatly in size and processing power. The common denominator however, is that all these devices will require the optimal delivery of networked multimedia data.One interesting problem is the delay imposed upon mobile receivers when switching between wireless cells. We provide a solution to this in the form of an extension of Mobile IP's hand-off algorithm. Our solution involves the exploitation of mobility prediction to predict a mobile terminal's future location based on its previous history (i.e., the last cell that it has been in) and for the media stream to be already present and cached by next cells base station ready for receiving by the mobile device.We cater specifically for continuous media applications, which can be especially effected by severe degradation in quality due to movement between cells. We present the results of a series of simulations of the Mobile IP++ protocol, which demonstrate the effectiveness of the ad-hoc protocol when mobile hosts move in predictable patterns between cells.     

Attention processes in children with shunted hydrocephalus versus attention deficit-hyperactivity disorder.

Children with congenital hydrocephalus, children with attention deficit-hyperactivity disorder, and normal controls were evaluated with measures of focused attention (Visual Orienting and Detection Task), sustained attention (continuous performance test), and attention shifting (Wisconsin Card Sorting Test). Components from these tasks have been linked to attention systems mediated by anterior or posterior brain networks. Children with congenital hydrocephalus showed an inability to focus and shift attention, which specifically implicated impairment of the disengage and move components of the posterior brain attention system. Children with attention deficit- hyperactivity disorder displayed the expected performance patterns on measures of focused attention once their difficulties with sustained attention were taken into account. However, they showed problems with shifting and sustaining attention, which are commonly associated with the anterior brain attention system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The proof of the pudding: An illustration of the relative strengths of null hypothesis, meta-analysis, and Bayesian analysis.

Some methodologists have recently suggested that scientific psychology's overreliance on null hypothesis significance testing (NHST) impedes the progress of the discipline. In response, a number of defenders have maintained that NHST continues to play a vital role in psychological research. Both sides of the argument to date have been presented abstractly. The authors take a different approach to this issue by illustrating the use of NHST along with 2 possible alternatives (meta-analysis as a primary data analysis strategy and Bayesian approaches) in a series of 3 studies. Comparing and contrasting the approaches on actual data brings out the strengths and weaknesses of each approach. The exercise demonstrates that the approaches are not mutually exclusive but instead can be used to complement one another. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perfectionism as a predictor of subsequent adjustment: Evidence for a specific diathesis–stress mechanism among college students.

The relations among perfectionism, stress, subsequent psychological symptoms, and hopelessness were examined among 215 college students. Hierarchical regression analyses were conducted to determine whether dimensions of perfectionism (P. Hewitt & G. Flett, 1991) predicted psychological symptoms and hopelessness (1 month later), and the extent to which stress scores added incremental validity to these predictions. Results indicated that socially prescribed perfectionism was a significant predictor of both adjustment measures. In addition, stress accounted for a significant amount of additional variance in predicting adjustment beyond perfectionism. Consistent with a diathesis–stress model, a significant Perfectionism × Stress interaction was found in predicting scores on adjustment measures beyond perfectionism and stress. However, this interaction was only found for socially prescribed perfectionism. Results provide support for a specific diathesis–stress mechanism and important implications for developing specific interventions in working with perfectionistic college students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Getting past setup obstacles,and moving to implementation,for law firm ADR groups

In the second of two parts, Kevin R. Casey, of Malvern, Pa., provides the tools to establish a comprehensive law firm alternative dispute resolution department. He covers ways to address attorney ambivalence, and lists implementation steps that will help the prospects for a well‐rounded, profitable program     

Characterisation of organic-inorganic hybrid coatings deposited on aluminium substrates

Optically transparent silica-based single amorphous phase organic-inorganic hybrid coating materials with differing organic/inorganic ratios have been prepared by a novel patented sol-gel process and deposited using a simple angled flow coating method on commercially pure aluminium substrates. Transmission electron microscopy and scanning electron microscopy were used to characterise the microstructures of the hybrid materials and the quality of the interfaces between the coatings and the aluminium substrates. The scratch resistance, critical load to failure and failure modes of these hybrid coating materials were studied using a simple scratch test. The coatings produced were all shown to adhere well to the aluminium substrates and exhibit good levels of scratch resistance.     

Sequence‐Specific HCV RNA Quantification Using the Size‐Dependent Nonlinear Optical Properties of Gold Nanoparticles

The hepatitis C virus (HCV) is a single‐stranded (ss) RNA virus that is responsible for chronic liver diseases, such as cirrhosis, end‐stage liver disease, and hepatocellular carcinoma. Driven by the need to detect the presence of the HCV viral sequence, herein it is demonstrated for the first time that the nonlinear optical (NLO) properties of gold nanoparticles can be used for screening and quantifying HCV RNA without any modification, with excellent detection limit (80 pM ) and selectivity (single base‐pair mismatch). The hyper‐Rayleigh scattering (HRS) intensity increases 25 times when label‐free, 145‐mer, HCV ss‐RNA is hybridized with 400 pM target RNA. The mechanism of HRS intensity change is discussed with experimental evidence for a higher multipolar contribution to the NLO response of gold nanoparticles.     

The effects of item composition,tag inlay design,reader antenna polarization,power and transponder orientation on the dynamic coupling efficiency of backscatter ultra‐high frequency radio frequency identification

The effects of packaged content, packaging material, transponder inlay design, reader antenna polarization, interrogation power and transponder orientation on the detection rate of ultra‐high frequency radio frequency identification (UHF RFID) passive transponders were studied. The influence of individual factors and their interactions were determined using general linear model analysis of variance. Influences originated in order of importance, from sample type, antenna polarization, power and inlay design. Important interactions in decreasing order of significance exist between: power and antenna polarization; sample type and antenna polarization; sample type and inlay design; inlay design and antenna polarization; sample type, power and antenna polarization; sample type and power; inlay design and power; sample type, inlay design and power. It was also observed that random orientation of tags did not cause a statistically significant variation in tag detection rate. It can be concluded that the use of UHF RFID for item level of food requires multi‐parameter assessment before hand. Copyright © 2009 John Wiley & Sons, Ltd.     

The discovery of the nonindigenous,mottled fingernail clam, Eupera cubensis (Prime, 1865) (Bivalvia: Sphaeriidae) in the Chicago Sanitary and Ship Canal (Illinois River Drainage), Cook County,Illinois

The nonindigenous mottled fingernail clam, Eupera cubensis is reported from the Upper Mississippi River Basin for the first time. This record represents a significant northern range expansion for the species in the United States. It appears to be presently confined to a 35-km stretch of the Chicago Sanitary and Ship Canal (CSSC), an artificial waterway that connects the Mississippi River drainage to the Great Lakes. Although the introduction of this species to the Great Lakes basin poses uncertain risks to the general aquatic community, the immediate effects of Eupera cubensis on the fauna of the CSSC are expected to be minimal.