Influence of Wettability and Reactivity on Refractory Degradation – Interactions of Molten Iron and Slags with Steelmaking Refractories at 1550°C

Refractories, materials that can withstand high temperatures, play an important role in the iron and steel sector which alone accounts for ~70% of total refractories produced. In this chapter, detailed wettability and interfacial phenomena investigations on alumina-carbon and zirconia-carbon refractories at steelmaking temperatures. The wettability between refractory substrates and molten iron/slags was investigated at 1550°C using the sessile drop approach in a horizontal tube furnace equipped with a CCD camera. Detailed experimental results were obtained on alumina-carbon/molten iron system at high temperatures. Alumina is known to be non-wetting to molten iron while carbon can be easily wetted. Observed contact angles were found to depend strongly on the substrate composition and contact time. While the refractory substrates containing 50 and 60% carbon were found to be non-wetting to molten iron, the substrates containing higher amounts of C (≥ 70%) were found to become increasingly wetting. Molten iron droplets were seen to spread on these substrates

Measuring and Analysing the Chain of Implicit Trust: AStudy of Third-party Resources Loading

The web is a tangled mass of interconnected services, whereby websites import a range of external resources from various third-party domains. The latter can also load further resources hosted on other domains. For each website, this creates a dependency chain underpinned by a form of implicit trust between the first-party and transitively connected third parties. The chain can only be loosely controlled as first-party websites often have little, if any, visibility on where these resources are loaded from. This article performs a large-scale study of dependency chains in the web to find that around 50% of first-party websites render content that they do not directly load. Although the majority (84.91%) of websites have short dependency chains (below three levels), we find websites with dependency chains exceeding 30. Using VirusTotal, we show that 1.2% of these third parties are classified as suspicious—although seemingly small, this limited set of suspicious third parties have remarkable reach into the wider ecosystem. We find that 73% of websites under-study load resources from suspicious third parties, and 24.8% of first-party webpages contain at least three third parties classified as suspicious in their dependency chain. By running sandboxed experiments, we observe a range of activities with the majority of suspicious JavaScript codes downloading malware

Mobile Computing in Physics Analysis - An Indicator for eScience

This paper presents the design and implementation of a Grid-enabled physics analysis environment for handheld and other resource-limited computing devices as one example of the use of mobile devices in eScience. Handheld devices offer great potential because they provide ubiquitous access to data and round-the-clock connectivity over wireless links. Our solution aims to provide users of handheld devices the capability to launch heavy computational tasks on computational and data Grids, monitor the jobs status during execution, and retrieve results after job completion. Users carry their jobs on their handheld devices in the form of executables (and associated libraries). Users can transparently view the status of their jobs and get back their outputs without having to know where they are being executed. In this way, our system is able to act as a high-throughput computing environment where devices ranging from powerful desktop machines to small handhelds can employ the power of the Grid. The results shown in this paper are readily applicable to the wider eScience community.Comment: 8 pages, 7 figures. Presented at the 3rd Int Conf on Mobile Computing & Ubiquitous Networking (ICMU06. London October 200

Environmental Impact of Processing Electronic Waste – Key Issues and Challenges

Extensive utilization of electric and electronic equipment in a wide range of applications has resulted in the generation of huge volumes of electronic waste (e-waste) globally. Highly complex e-waste can contain metals, polymers and ceramics along with several hazardous and toxic constituents. There are presently no standard approaches for handling, dismantling, and the processing of e-waste to recover valuable resources. Inappropriate and unsafe practices produce additional hazardous compounds and highly toxic emissions as well. This chapter presents an overview of the environmental impact of processing e-waste with specific focus on toxic elements present initially in a variety of e-waste as well as hazardous compounds generated during e-waste processing. Hazardous constituents/ and contaminants were classified in three categories: primary contaminants, secondary contaminants, and tertiary contaminants. Primary contaminants represent hazardous substances present initially within various types of e-waste; these include heavy metals such as lead, mercury, nickel and cadmium, flame retardants presents in polymers etc. Secondary contaminants such as spent acids, volatile/toxic compounds, PAHs are the by-products or waste residues produced after inappropriate processing of e-waste and the tertiary contaminants include leftover reagents or compounds used during processing. A detailed report is presented on the environmental impact of processing e-waste and the detrimental impact on soil contamination, vegetation degradation, water and air quality along with implications for human health. Challenges and opportunities associated with appropriate e-waste management are also discussed

Sub-Riemannian Fast Marching in SE(2)

We propose a Fast Marching based implementation for computing sub-Riemanninan (SR) geodesics in the roto-translation group SE(2), with a metric depending on a cost induced by the image data. The key ingredient is a Riemannian approximation of the SR-metric. Then, a state of the art Fast Marching solver that is able to deal with extreme anisotropies is used to compute a SR-distance map as the solution of a corresponding eikonal equation. Subsequent backtracking on the distance map gives the geodesics. To validate the method, we consider the uniform cost case in which exact formulas for SR-geodesics are known and we show remarkable accuracy of the numerically computed SR-spheres. We also show a dramatic decrease in computational time with respect to a previous PDE-based iterative approach. Regarding image analysis applications, we show the potential of considering these data adaptive geodesics for a fully automated retinal vessel tree segmentation.Comment: CIARP 201

The potential and environmental benefits of developing renewable energy strategy: a comparative analysis of Pakistan and developed countries

Renewable energy is being developed globally to overcome the depletion of natural resources and mitigating the global issue of climate change. The increasing energy crisis and environmental concerns make renewable energy more critical for a sustainable future. Renewable energy technologies have a great potential across the globe. Pakistan being a developing country is continuously facing energy crisis and an emphasis on industrialization is increasing carbon emissions. Renewable energy development provides necessary solutions, particularly in developing countries where energy demands have to be met through an economical and environmental friendly way. This paper explores the significance and potential of renewable energy development in developing countries i.e. Pakistan and how it can contribute to reduce the environmental impacts for mitigating climate change. It argues that the current policy measures and infrastructure is inadequate to implement renewable energy technologies, also discussing various renewable energy sources. The critical review of the literature and case-based experiences has been used as an overall approach to this paper. It will help in exploring renewable energy strategy and its implementation in developing countries in comparison to developed economies. It concludes with an integrated and comprehensive policy recommendations and possible solutions to develop a strategic approach to renewable energy

Recent advancements of n-doped graphene for rechargeable batteries: A review

Graphene, a 2D carbon structure, due to its unique materials characteristics for energy storage applications has grasped the considerable attention of scientists. The highlighted properties of this material with a mechanically robust and highly conductive nature have opened new opportunities for different energy storage systems such as Li-S (lithium-sulfur), Li-ion batteries, and metal-air batteries. It is necessary to understand the intrinsic properties of graphene materials to widen its large-scale applications in energy storage systems. In this review, different routes of graphene synthesis were investigated using chemical, thermal, plasma, and other methods along with their advantages and disadvantages. Apart from this, the applications of N-doped graphene in energy storage devices were discussed

Perancangan Lengan Robot 5 Derajat Kebebasan Dengan Pendekatan Kinematika

This study discusses the design of arm robot model with 5 degree of freedom that is designed to be a small-scale model of the articulated robot industry to simulate the movement of the robots industry. The objective of this research is to build a real arm robot based on kinematic aspects with the movement of waist, shoulder, elbow, wrist pitch, wrist roll and gripper, and to analyze the robot movement. The design includes building the real arm robot based on Arduino Uno board controller and the movement of the robot using servo motor DC. The robot can be controlled automatically from the computer with the RS-232 or USB port interface and it learns about the kinematic of the robot\u27s arm when an experiment on the forward kinematic is accomplished. The robot was running well, with the maximum distance that can be reached by the robot on the coordinate axis x = 425 mm, y = 425 mm and z = 480 mm