16,511 research outputs found
The Youth Correction Authority Act
Since wireless communication has become a standard feature in the daily life, smartphones and tablets among other things are integrated with the Bluetooth technology. While in some parts of the day wireless communication can be used for searching the internet and share information on social networks without the need of having a secure connection, there are some other parts where the security might become of high importance. When the technology gets integrated in companies the security problem becomes more evident. This is because when the radio signals spread in the medium they can be accessed by anyone that is in reach in the network and the information that was sent may not be intended for everyone. To secure the network from unintended users becomes important when handling fragile information, which companies may deal with daily. Â This paper gives an introduction on which security features and techniques that already exist in some personal area networks. From this it has been clear that a security feature could be implemented on the baseband layer of Bluetooth to increase the secrecy during the transmission since at the moment security is only implemented on higher layers using encryption algorithms. Â This paper proposes a conceptual idea of improving the secrecy in the network by using a wiretap code that is implemented before the error-correction coding in the Bluetooth's baseband. By disabling the ARQ scheme in Bluetooth one can modulate the channel as a Packet Erasure Channel that will lose packet with a certain probability. By using a nested code structure, the message can then be securely sent by using a higher rate than what the eavesdropper can recover due to the amount of errors the received signal will have. The performance of the concept is evaluated with the secrecy throughput, secrecy outage and the leakage
The Legal Approach to Crime and Correction
This report documents the research and experiments on evaluating the possibilities of using OpenCV for developing a markerless augmented reality applications using the structure from motion algorithm. It gives a background on what augmented reality is and how it can be used and also theory about camera calibration and the structure from motion algorithm is presented. Based on the theory the algorithm was implemented using OpenCV and evaluated regarding its performance and possibilities when creating markerless augmented reality applications
Designs for generalized linear models with random block effects via information matrix approximations
The selection of optimal designs for generalized linear mixed models is complicated by the fact that the Fisher information matrix, on which most optimality criteria depend, is computationally expensive to evaluate. Our focus is on the design of experiments for likelihood estimation of parameters in the conditional model. We provide two novel approximations that substantially reduce the computational cost of evaluating the information matrix by complete enumeration of response outcomes, or Monte Carlo approximations thereof: (i) an asymptotic approximation which is accurate when there is strong dependence between observations in the same block; (ii) an approximation via Kriging interpolators. For logistic random intercept models, we show how interpolation can be especially effective for finding pseudo-Bayesian designs that incorporate uncertainty in the values of the model parameters. The new results are used to provide the first evaluation of the efficiency, for estimating conditional models, of optimal designs from closed-form approximations to the information matrix derived from marginal models. It is found that correcting for the marginal attenuation of parameters in binary-response models yields much improved designs, typically with very high efficiencies. However, in some experiments exhibiting strong dependence, designs for marginal models may still be inefficient for conditional modelling. Our asymptotic results provide some theoretical insights into why such inefficiencies occur
Solar Risk: How Energy Storage Can Preserve Solar Savings in California Affordable Housing
Recently, utilities and regulators in California have proposed policy changes and new electricity rate structures that could drastically erode the value of stand-alone solar in California. Those changes, through modifications to net metering, time-of-use rates, and demand charges, could hit solar installations in affordable housing especially hard.This report explores potential risks for California's multifamily affordable housing sector, and makes two important findings: (1) the changes would significantly reduce the value proposition for a stand-alone solar system, and (2) incorporating energy storage could potentially reverse these negative economic impacts
New VISTAs in Science Education
In the summer of 2012, a colleague and I attended the four-week Virginia Initiative for Science Teaching and Achievement (VISTA) Elementary Summer Science Institute where we were trained to conduct inquiry-based science teaching in a problem-based learning setting. We then implemented our training in our own academic classrooms by developing a Problem-Based Learning unit meeting the objectives of our Virginia standards-based science curriculum and selecting a topic with tics to our local community. Toward demonstrating that students, teachers, and educational systems stand to benefit from the implementation of this methodology, this article clarifies the following aspects: 1) outlines the problem, scenario, and process of developing a Problem-Based Leaming unit; 2) explains the delivery in the classroom; 3) analyzes ongoing formative and summative assessments; 4) and, discusses the influence on students, teachers, and instruction as a whole
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