A Reconfigurable Platform For Cognitive Radio

Today¿s rigid spectrum allocation scheme creates a spectrum scarcity problem for future wireless communications. Measurements show that a wide range of the allocated frequency bands are rarely used. Cognitive radio is a novel approach to improve the spectrum usage, which is able to sense the spectrum and adapt its transmission while coexisting with the licensed spectrum user. A reconfigurable radio platform is required to provide enough adaptivity for cognitive radio. In this paper, we propose a cognitive radio system architecture and discuss its possible implementation on a heterogeneous reconfigurable radio platform

Adaptive OFDM System Design For Cognitive Radio

Recently, Cognitive Radio has been proposed as a promising technology to improve spectrum utilization. A highly flexible OFDM system is considered to be a good candidate for the Cognitive Radio baseband processing where individual carriers can be switched off for frequencies occupied by a licensed user. In order to support such an adaptive OFDM system, we propose a Multiprocessor System-on-Chip (MPSoC) architecture which can be dynamically reconfigured. However, the complexity and flexibility of the baseband processing makes the MPSoC design a difficult task. This paper presents a design technology for mapping flexible OFDM baseband for Cognitive Radio on a multiprocessor System-on-Chip (MPSoC)

Weighted Class Complexity: A Measure of Complexity for Object Oriented System

Software complexity metrics are used to predict critical information about reliability and maintainability of software systems. Object oriented software development requires a different approach to software complexity metrics. In this paper, we propose a metric to compute the structural and cognitive complexity of class by associating a weight to the class, called as Weighted Class Complexity (WCC). On the contrary, of the other metrics used for object oriented systems, proposed metric calculates the complexity of a class due to methods and attributes in terms of cognitive weight. The proposed metric has been demonstrated with OO examples. The theoretical and practical evaluations based on the information theory have shown that the proposed metric is on ratio scale and satisfies most of the parameters required by the measurement theor

An Approach for the Empirical Validation of Software Complexity Measures

Software metrics are widely accepted tools to control and assure software quality. A large number of software metrics with a variety of content can be found in the literature; however most of them are not adopted in industry as they are seen as irrelevant to needs, as they are unsupported, and the major reason behind this is due to improper empirical validation. This paper tries to identify possible root causes for the improper empirical validation of the software metrics. A practical model for the empirical validation of software metrics is proposed along with root causes. The model is validated by applying it to recently proposed and well known metrics

Evaluation Criteria for Object-oriented Metrics

In this paper an evaluation model for object-oriented (OO) metrics is proposed. We have evaluated the existing evaluation criteria for OO metrics, and based on the observations, a model is proposed which tries to cover most of the features for the evaluation of OO metrics. The model is validated by applying it to existing OO metrics. In contrast to the other existing criteria, the proposed model is simple in implementation and includes the practical and important aspects of evaluation; hence it suitable to evaluate and validate any OO complexity metric

For better or for worse? Investigating the meaning of change

For most, change makes a regular appearance in everyday life and has the capacity to usher in excitement, growth, and chaos. Due to the variable nature of change, people may hold subjective definitions of what “change” typically means. Across four studies, we examine the possibility that there are meaningful individual differences in the dominant subjective definitions people hold about the nature of change. Study 1 and 2 investigated the spontaneous associations participants make when asked to think about change, and found that holding a positive or negative general view about change (as measured by the Nature of Change scale, developed by the researchers) predicts the valence of self-generated associations. Studies 1 and 2 also demonstrate that people with an implicit entity theory of change (believing that people largely cannot change) report more negative and less positive dominant definitions of change than incremental theorists who believe people’s attributes are changeable. Study 3 expands on this finding to demonstrate a link between beliefs about the Nature of Change and beliefs about the role of effort in attributions of success. Participants who believe change is positive, predictable and controllable are more likely to believe that success is a product of effort than participants who believe change is negative, unpredictable and uncontrollable. Definitions of change predict success attributions over and above people’s implicit incremental or entity theories, which have previously been shown to predict attributions. Finally, Study 4 investigates the possibility that more precise definitions of change (as improvement, decline, or random) would alter people’s responses to the implicit theories scale, demonstrating that responses are somewhat contingent on definitions of change Further, change defined as improvement, decline, or random differentially predicted success attributions, which are also again predicted by people’s Nature of Change definitions. Overall, the current set of studies demonstrates that individual differences in people’s reactions to change are important to consider and may be as dynamic and diverse as change itself

Temperature Dependence of a Sub-wavelength Compact Graphene Plasmon-Slot Modulator

We investigate a plasmonic electro-optic modulator with an extinction ratio exceeding 1 dB/um by engineering the optical mode to be in-plane with the graphene layer, and show how lowering the operating temperature enables steeper switching. We show how cooling Graphene enables steeping thus improving dynamic energy consumption. Further, we show that multi-layer Graphene integrated with a plasmonic slot waveguide allows for in-plane electric field components, and 3-dB device lengths as short as several hundred nanometers only. Compact modulators approaching electronic length-scales pave a way for ultra-dense photonic integrated circuits with smallest footprint