1,355 research outputs found
Ultracompact and low-power optical switch based on silicon photonic crystals
Switching light is one of the most fundamental functions of an optical circuit. As such, optical switches are a major research topic in photonics, and many types of switches have been realized. Most optical switches operate by imposing a phase shift between two sections of the device to direct light from one port to another, or to switch it on and off, the major constraint being that typical refractive index changes are very small. Conventional solutions address this issue by making long devices, thus increasing the footprint, or by using resonant enhancement, thus reducing the bandwidth. We present a slow-light-enhanced optical switch that is 36 times shorter than a conventional device for the same refractive index change and has a switching length of 5.2 m.The work was funded through the EU FP6-FET
“Splash” project and we acknowledge the Nanostructuring
Platform of EU FP6-NoE “epixnet” for technical
support. T. P. White is supported by an 1851
Royal Commission Research Fellowship
Feeling the future: A meta-analysis of 90 experiments on the anomalous anticipation of random future events
In 2011, one of the authors (DJB) published a report of nine experiments in the Journal of Personality and Social Psychology purporting to demonstrate that an individual\u2019s cognitive and affective responses can be influenced by randomly selected stimulus events that do not occur until after his or her responses have already been made and recorded, a generalized variant of the phenomenon traditionally denoted by the term precognition. To encourage replications, all materials needed to conduct them were made available on request. We here report a meta-analysis of 90 experiments from 33 laboratories in 14 countries which yielded an overall effect greater than 6 sigma, z = 6.40, p = 1.2
7 10 with an effect size (Hedges\u2019 g) of 0.09. A Bayesian analysis yielded a Bayes Factor of 5.1
7 10 , greatly exceeding the criterion value of 100 for \u201cdecisive evidence\u201d in support of the experimental hypothesis. When DJB\u2019s original experiments are excluded, the combined effect size for replications by independent investigators is 0.06, z = 4.16, p = 1.1
7 10 , and the BF value is 3,853, again exceeding the criterion for \u201cdecisive evidence.\u201d The number of
potentially unretrieved experiments required to reduce the overall effect size of the complete database to a trivial value of 0.01 is 544, and seven of eight additional statistical tests support the conclusion that the database is not significantly compromised by either selection bias or by intense \u201cp -hacking\u201d\u2014the selective suppression of findings or analyses that failed to yield statistical significance. P-curve analysis, a recently introduced statistical technique, estimates the true effect size of the experiments to be 0.20 for the complete database and 0.24 for the independent replications, virtually identical to the effect size of DJB\u2019s original experiments (0.22) and the closely related \u201cpresentiment\u201d experiments (0.21). We discuss the controversial status of precognition and other anomalous effects collectively known as psi
An Incremental Navigation Localization Methodology for Application to Semi-Autonomous Mobile Robotic Platforms to Assist Individuals Having Severe Motor Disabilities.
In the present work, the author explores the issues surrounding the design and development of an intelligent wheelchair platform incorporating the semi-autonomous system paradigm, to meet the needs of individuals with severe motor disabilities. The author presents a discussion of the problems of navigation that must be solved before any system of this type can be instantiated, and enumerates the general design issues that must be addressed by the designers of systems of this type. This discussion includes reviews of various methodologies that have been proposed as solutions to the problems considered. Next, the author introduces a new navigation method, called Incremental Signature Recognition (ISR), for use by semi-autonomous systems in structured environments. This method is based on the recognition, recording, and tracking of environmental discontinuities: sensor reported anomalies in measured environmental parameters. The author then proposes a robust, redundant, dynamic, self-diagnosing sensing methodology for detecting and compensating for hidden failures of single sensors and sensor idiosyncrasies. This technique is optimized for the detection of spatial discontinuity anomalies. Finally, the author gives details of an effort to realize a prototype ISR based system, along with insights into the various implementation choices made
Small Enterprise Strategies in an Unstable Public Environment
Many small business owners in the United States dream about getting a large contract with the federal government, feeling that their lives would be easier if they did. Ironically, there have been numerous occasions where small businesses have gone out of business after being overwhelmed by a government contract. This case study addresses how small businesses can improve their survival and success rate in the public sector with a strategic approach to their operations. It begins by discussing the preparation that goes into federal contracting by small businesses. Case examples of four American companies involved in contracting with the Department of Energy are evaluated. Data collection is achieved through qualitative analysis. The application of these conclusions could increase the survival rate of small businesses operating in an unstable public environment. The study is significant because this research widens contemporary assumptions about strategic thinking for small businesses engaged in government contracting
Small Enterprise Strategies in an Unstable Public Environment
Many small business owners in the United States dream about getting a large contract with the federal government, feeling that their lives would be easier if they did. Ironically, there have been numerous occasions where small businesses have gone out of business after being overwhelmed by a government contract. This case study addresses how small businesses can improve their survival and success rate in the public sector with a strategic approach to their operations. It begins by discussing the preparation that goes into federal contracting by small businesses. Case examples of four American companies involved in contracting with the Department of Energy are evaluated. Data collection is achieved through qualitative analysis. The application of these conclusions could increase the survival rate of small businesses operating in an unstable public environment. The study is significant because this research widens contemporary assumptions about strategic thinking for small businesses engaged in government contracting
Novel pharmacotherapeutic treatments for cocaine addiction
Cocaine is a stimulant that leads to the rapid accumulation of catecholamines and serotonin in the brain due to prevention of their re-uptake into the neuron that released the neurotransmitter. Cocaine dependence is a public health concern and cause of significant morbidity and mortality worldwide. At present, there are no approved medications for the treatment of this devastating illness, and behavioral interventions have proven to be of limited use. However, there have been a number of recent trials testing promising agents including dopamine agonists, GABAergic medications and the cocaine vaccine. Here we discuss the most recent human clinical trials of potential medications for treatment of cocaine dependence, as well as pre-clinical studies for another promising agent, levo tetrahydropalmatine. Examination of these recent findings shows promise for GABAergic medications and the cocaine vaccine, as well as unique medications such as disulfiram, whose mechanism remains to be determined. Future work may also confirm specific subgroups of patients for treatment response based on clinical characteristics, biomarkers and pharmacogenetics. This review highlights the need for further, bigger studies in order to determine optimal clinical usage
Raising Disability Awareness and Self-Efficacy of One-Stop Workforce Center Staff Serving Job Seekers with Disabilities
Under the Workforce Investment Act of 1998 (WIA) access to employment services for all job seekers, including those with disabilities, is available partly through a system of One-Stop Workforce Centers (Storen & Dixon, 1999; U.S. Department of Labor, 2001). However, early studies of WIA implementation found that One-Stops had limited outreach to and lacked accessibility for people with disabilities. This article describes a training program designed to raise disability awareness and self-efficacy of One-Stop staff serving people with disabilities, and to contribute to a unified culture of sensitivity toward, and an ability to work with, job seekers with disabilities
A Criteria-Based Approach to the Traveling Salesman Problem (TSP)
The “traveling salesman problem (TSP)” is a classic minimum cost network flow problem in mathematical programming and graph theory that can be formulated in multiple configurations. The fundamental question, however, is: “what is a cost”? The original “traveling salesman problem (TSP)” defines distance as the cost and the objective is to minimize distance traveled. This paper proposes other “cost” criteria to the original problem and also proposes a maximum revenue network flow as a variant to improve managerial decision-making. The proposed decision table methodology can be applied to problems that involve multiple locations or multiple tasks to complete
“Kids are in the middle of it” – Child protection practitioners reflect on indicators of coercive control and situational couple violence
How relevant is differentiating between coercive control and situational couple violence in statutory child protection practice with families experiencing domestic and family violence?
In this small scale self-selected qualitative study we interviewed six Australian child protection practitioners and asked them to consider four fictional vignettes, two containing indicators of high levels of coercive control and two containing indicators of situational couple violence. We asked participants to reflect on whether the vignettes represented the kind of situations they encounter in practice and how they would be likely to respond.
Participants indicated that both coercive control and situational couple violence were common in their practice and that each of these violence types presented challenges. They highlighted a range of priorities and challenges for meeting the needs of children in families experiencing violence who come to the attention of statutory child protection authorities. Further, they noted the need to acknowledge the impact on children and young people when neither parent or caregiver can parent in a non-violent and safe manner.
Child protection practice frameworks should address the risk of harm to children and young people posed by situational couple violence, and not just coercive control
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