Estimation of Defects Based on Defect Decay Model: ED^{3}M

An accurate prediction of the number of defects in a software product during system testing contributes not only to the management of the system testing process but also to the estimation of the product's required maintenance. Here, a new approach called ED³M is presented that computes an estimate of the total number of defects in an ongoing testing process. ED³M is based on estimation theory. Unlike many existing approaches the technique presented here does not depend on historical data from previous projects or any assumptions about the requirements and/or testers' productivity. It is a completely automated approach that relies only on the data collected during an ongoing testing process. This is a key advantage of the ED³M approach, as it makes it widely applicable in different testing environments. Here, the ED³M approach has been evaluated using five data sets from large industrial projects and two data sets from the literature. In addition, a performance analysis has been conducted using simulated data sets to explore its behavior using different models for the input data. The results are very promising; they indicate the ED³M approach provides accurate estimates with as fast or better convergence time in comparison to well-known alternative techniques, while only using defect data as the input.     

Local calibration of rigid pavement performance models using resampling methods

The performance prediction models in the Pavement-ME design software are nationally calibrated using in-service pavement material properties, pavement structure, climate and truck loadings, and performance data obtained from the Long-Term Pavement Performance programme. The nationally calibrated models may not perform well if the inputs and performance data used to calibrate those do not represent the local design and construction practices. Therefore, before implementing the new M-E design procedure, each state highway agency (SHA) should evaluate how well the nationally calibrated performance models predict the measured field performance. The local calibrations of the Pavement-ME performance models are recommended to improve the performance prediction capabilities to reflect the unique conditions and design practices. During the local calibration process, the traditional calibration techniques (split sampling) may not necessarily provide adequate results when limited number of pavement sections are available. Consequently, there is a need to employ statistical and resampling methodologies that are more efficient and robust for model calibrations given the data related challenges encountered by SHAs. The main objectives of the paper are to demonstrate the local calibration of rigid pavement performance models and compare the calibration results based on different resampling techniques. The bootstrap is a non-parametric and robust resampling technique for estimating standard errors and confidence intervals of a statistic. The main advantage of bootstrapping is that model parameters estimation is possible without making distribution assumptions. This paper presents the use of bootstrapping and jackknifing to locally calibrate the transverse cracking and IRI performance models for newly constructed and rehabilitated rigid pavements. The results of the calibration show that the standard error of estimate and bias are lower compared to the traditional sampling methods. In addition, the validation statistics are similar to that of the locally calibrated model, especially for the IRI model, which indicates robustness of the local model coefficients.     

SPACE: A lightweight collaborative caching for clusters

In this paper, we introduce Systematic P2P Aided Cache Enhancement or SPACE, a new collaboration scheme among clients in a computer cluster of a high performance computing facility to share their caches with each other. The collaboration is achieved in a distributed manner, and is designed based on peer-to-peer computing model. The objective is to provide (1) a decentralized solution, and (2) a near optimal performance with reasonably low overhead. Simulation results are given to demonstrate the performance of the proposed scheme. In addition, the results show that SPACE evenly distributes work loads among participators, and entirely eliminates any requirement of a central cache manager.     

Keyboard design through physiological strain measurements

The physiologically tolerable range of positions for the joints of the upper extremities have been investigated for typing tasks by recording the myoelectric activities of the involved muscles. For long-term typing tasks a split keyboard is recommended allocating a key field to each hand. The fields should be rotated against each other in the horizontal plane and inclined laterally.     

Comparison of Performance of Packet Scheduling Algorithms in LTE-A HetNets

The concept of usage of heterogeneous networks (HetNets) is about improving the LTE system performance by increasing the capacity and coverage of the Macro cell. In this paper, a performance comparison of various packet scheduling algorithms such as Proportional Fair, Maximum Largest Weighted Delay First and Exponential/Proportional Fair is studied in detail in the HetNets environment. The key performance indicators such as throughput, packet loss ratio, delay and fairness are considered to judge the performance of the scheduling algorithms. Various strategies such as increasing the number of Pico cells in the cell edge were used in the simulation for the performance evaluation study. The results achieved through various simulations show that adding Pico cells to the existing Macros enhances the overall system performance in addition to the various scheduling algorithms implemented in Macros. For reader’s convenience, various types of graphs have been used to represent the simulation results to better understand the performance metrics of various scheduling algorithms. Simulation results shows that overall system gain has increased because of adding Picos and thereby providing better coverage in the cell edge areas and thereby increasing the capacity of the network to provide better quality of service.     

Four-wave mixing reduction technique based on smart filter approach

This paper proposed a new technique to suppress the four-wave mixing (FWM) effect by using a smart filter technique. The behaviour of FWM and the performance of wavelength division multiplexing systems with 4 and 16 channels were simulated in the presence of the proposed technique. The simulation was also performed under different parameters such as input power, number of channels and channel spacing. The FWM power drastically decreases by 12 and 19 dB for the 4 and 16 channels, respectively, when the smart filter is used as compared with the conventional system. In terms of system performance, the suggested approach for 4 and 16 channels at the first channel offers low bit error rate (BER) values of 3.23 × 10^?23 and 1.7 × 10^?21, respectively. The smart filter with the channel spacing variation for the 4-channel system subsequently improved the BER value at the fourth channel. Results confirm that the smart filter approach is an active solution that can suppress the FWM effect in optical transmission systems.     

Robotic System for Closed-Bore MRI-Guided Prostatic Interventions

This paper reports on the development of a new closed-bore magnetic resonance imaging (MRI) compatible robotic system for image-guided prostatic interventions: ablation, brachytherapy, and biopsy. The first stage of development addresses only laser-based ablation. The robot actuators are ultrasonic motors. The first physical robot prototype was manufactured and tested in the MRI with an ablation tool. The tests covered magnetic resonance (MR) compatibility, tool visualization, and robot control accuracy. Robot tip position error is less than 2 mm at points closer than 0.5 m to the isocenter. A method to control ultrasonic motors for MRI-compatibility is reported.     

Robust Multimodal Biometric System Based on Feature Level Fusion of Optimiseddeepnet Features

Wireless Personal Communications - Multimodal biometric systems combine feature knowledge from multiple traits to overcome shortcomings of unimodal systems. However, most of the traditional...     

An overview of state of the art and research in the fields of sensible, latent and thermo-chemical thermal energy storage

Due to the increase in volatile renewable power and heat generation (wind or solar), thermal energy storage (TES) has obtained growing importance and interest. The technology can be distinguished into three main types: sensible, latent and thermochemical storage. Apart from low and medium temperature heat applications, high temperature TES also is an attractive means to store power in the form of heat (before the thermodynamic transformation process). Thermochemical storage allows for long duration seasonal storage of energy.