A Reactive and Efficient Walking Pattern Generator for Robust Bipedal Locomotion

Available possibilities to prevent a biped robot from falling down in the presence of severe disturbances are mainly Center of Pressure (CoP) modulation, step location and timing adjustment, and angular momentum regulation. In this paper, we aim at designing a walking pattern generator which employs an optimal combination of these tools to generate robust gaits. In this approach, first, the next step location and timing are decided consistent with the commanded walking velocity and based on the Divergent Component of Motion (DCM) measurement. This stage which is done by a very small-size Quadratic Program (QP) uses the Linear Inverted Pendulum Model (LIPM) dynamics to adapt the switching contact location and time. Then, consistent with the first stage, the LIPM with flywheel dynamics is used to regenerate the DCM and angular momentum trajectories at each control cycle. This is done by modulating the CoP and Centroidal Momentum Pivot (CMP) to realize a desired DCM at the end of current step. Simulation results show the merit of this reactive approach in generating robust and dynamically consistent walking patterns

Distributed optimization framework for in-network data processing

In-Network Processing (INP) is an effective way to aggregate and process data from different sources and forward the aggregated data to other nodes for further processing until it reaches the end user. There is a trade-off between energy consumption for processing data and communication energy spent on transferring the data. Specifically, aggressive data aggregation consumes much energy for processing, but results in less data for transmission, thus using less energy for communications, and vice versa. An essential requirement in the INP process is to ensure that the user expectation of quality of information (QoI) is delivered during the process. Using wireless sensor networks for illustration and with the aim of minimising the total energy consumption of the system, we study and formulate the trade-off problem as a nonlinear optimisation problem where the goal is to determine the optimal data reduction rate, while satisfying the QoI required by the user. The formulated problem is a Signomial Programming (SP) problem, which is a non-convex optimisation problem and very hard to be solved directly. We propose two solution frameworks. First, we introduce an equivalent problem which is still SP and non-convex as the original one, but we prove that the strong duality property holds, and propose an efficient distributed algorithm to obtain the optimal data reduction rates, while delivering the required QoI. The second framework applies to the system with identical nodes and parameter settings. In such cases, we prove that the complexity of the problem can be reduced logarithmically. We evaluate our proposed frameworks under different parameter settings and illustrate the validity and performance of the proposed techniques through extensive simulation

A new revenue maximization model using customized plans in cloud service allocation (Applied on a real company case study)

Cloud computing is emerging as a promising field offering a variety of computing services to end users. These services are offered at different prices using various pricing schemes and techniques. End users will favor the service provider offering the best quality with the lowest price. Therefore, applying a fair pricing model will attract more customers and achieve higher revenues for service providers. This work focuses on a novel dynamic pricing model which is able to satisfy advance users requirements based on normal fixed price model. This paper considers many factors that affect pricing and user satisfaction, such as fairness, QoS, SLA, and more, by highlighting their importance in recent markets and propose a flexible model which tries to utilize all resources to the highest capacity and offers low prices for underutilized resources. The simulated results shows the appropriateness of dynamic pricing for sharing of computing resources, where providers want to have more customers as a managerial decision and even more income in total.Keywords: Cloud Computing; Digital Pricing; Dynamic Pricin

Unbalanced chemical equations conversion to Mark-up format and representation to vision impaired students

This paper describes a method to represent unbalanced chemical equations to vision impaired students which allows them to navigate through classified data, such as species, elements, quantity numbers at the left and right hand sides of equations, reactants, and products. Then they can find appropriate coefficients and balance chemical equations without involving to mathematical aspects of balancing and remembering a lot of information. The goal of this research was the development of an application which assists vision impaired students enrolled in chemistry course to be able to read chemistry literature containing formulae, chemistry representations of elements, and other aspects of chemistry that has been difficult in the past to present in a way for vision impaired people to understand. Developed application by this research is an open source command line Bash Script application under Linux which accepts an unbalanced chemical equation as an input, processes, classifies information, and represents it as Mark-up format or Alternative Audio Descriptive using Text to Speech

A method to provide high volume transaction outputs accessibility to vision Impaired using layout analysis

The Documents in the financial services, insurance, utilities, and government sectors typically require a high volume of PDF documents to be generated which are stored for presentment or archived for legal purposes. As high volume transactional output (HVTO) demands put increasing pressure on online presentment capabilities, accessibility has become a growing concern. In particular, access to these files proposes significant challenges when these documents are presented to visually impaired people using assistive technologies (i.e. screen readers). Since it is rare that all recipients are prepared to accept electronic delivery of their documents, a large portion of the documents is still printed as PDFs. In an online billing system, bills are sent to customers’ email accounts as attached PDF files or HTML links. These bills in the most cases are neither accessible through assistive technologies nor useable by vision-impaired customers. This paper provides a method for HVTO documents automatic transformation to an accessible and navigable Mark-up format such as XML or Digital Accessible Information System (DAISY)

Practical segmentation methods for logical and geometric layout analysis to Improve scanned PDF accessibility to vision impaired

The use of electronic documents has rapidly increased in recent decades and the PDF is one the most commonly used electronic document formats. A scanned PDF is an image and does not actually contain any text. For the vision–impaired user who is dependent upon a screen reader to access this information, this format is not useful. Thus addressing PDF accessibility through assistive technology has now become an important concern. PDF layout analysis provides precious formatting information that supports PDF component classification. This classification facilitates the tag generation. Accurate tagging produces a searchable and navigable scanned PDF document. This paper describes several practical segmentation methods which are easy to implement and efficient for PDF layout analysis so that the scanned PDF document can be navigated or searched using assistive technologies

Converting Optically Scanned Regular or Irregular Tables to a Standardised Markup Format to be Accessible to Vision-Impaired

Documents use tables to communicate multidimensional information clearly, summarise and present data in an easy-to-interpret way. Tabular information in scanned PDF due to its nature without further processing is not accessible for vision-impaired people who use assistive technology such as screen readers. The lack of access to table contents limits educational and workplace opportunities for people with vision impairment. They require a complete equivalent to access table. This paper describes techniques which apply to scanned PDF document for table detection, extraction and cell segmentation to retrieve cell contents and represent them in a navigable manner to vision-impaired.The output is in mark-up format and provides navigation ability to access content of a table

Electric Power Grid Resilience to Cyber Adversaries: State of the Art

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The smart electricity grids have been evolving to a more complex cyber-physical ecosystem of infrastructures with integrated communication networks, new carbon-free sources of powergeneratio n, advanced monitoring and control systems, and a myriad of emerging modern physical hardware technologies. With the unprecedented complexity and heterogeneity in dynamic smart grid networks comes additional vulnerability to emerging threats such as cyber attacks. Rapid development and deployment of advanced network monitoring and communication systems on one hand, and the growing interdependence of the electric power grids to a multitude of lifeline critical infrastructures on the other, calls for holistic defense strategies to safeguard the power grids against cyber adversaries. In order to improve the resilience of the power grid against adversarial attacks and cyber intrusions, advancements should be sought on detection techniques, protection plans, and mitigation practices in all electricity generation, transmission, and distribution sectors. This survey discusses such major directions and recent advancements from a lens of different detection techniques, equipment protection plans, and mitigation strategies to enhance the energy delivery infrastructure resilience and operational endurance against cyber attacks. This undertaking is essential since even modest improvements in resilience of the power grid against cyber threats could lead to sizeable monetary savings and an enriched overall social welfare