5,966 research outputs found

    Separating Overlapping Tissue Layers from Microscopy Images

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    Manual preparation of tissue slices for microscopy imaging can introduce tissue tears and overlaps. Typically, further digital processing algorithms such as registration and 3D reconstruction from tissue image stacks cannot handle images with tissue tear/overlap artifacts, and so such images are usually discarded. In this paper, we propose an imaging model and an algorithm to digitally separate overlapping tissue data of mouse brain images into two layers. We show the correctness of our model and the algorithm by comparing our results with the ground truth

    Using Taint Analysis and Reinforcement Learning (TARL) to Repair Autonomous Robot Software

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    It is important to be able to establish formal performance bounds for autonomous systems. However, formal verification techniques require a model of the environment in which the system operates; a challenge for autonomous systems, especially those expected to operate over longer timescales. This paper describes work in progress to automate the monitor and repair of ROS-based autonomous robot software written for an a-priori partially known and possibly incorrect environment model. A taint analysis method is used to automatically extract the data-flow sequence from input topic to publish topic, and instrument that code. A unique reinforcement learning approximation of MDP utility is calculated, an empirical and non-invasive characterization of the inherent objectives of the software designers. By comparing off-line (a-priori) utility with on-line (deployed system) utility, we show, using a small but real ROS example, that it's possible to monitor a performance criterion and relate violations of the criterion to parts of the software. The software is then patched using automated software repair techniques and evaluated against the original off-line utility.Comment: IEEE Workshop on Assured IEEE Workshop on Assured Autonomous Systems, May, 202

    Introduction

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    Effect of Activated Charcoal and Composition Activator Acid Sulphate on Palm Oil Waste Water Treatment

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    Purpose of this research is to exploit the shell and palm fiber become the active charcoal, by looking at the influence of the ratio mixture composition and effect of activator. this Active charcoal application as adsorbent to the liquid waste of crude palm oil. Initial treatment, shells and palm fiber dried first at a temperature of 1200C and carbonized. charcoal mix shell and palm fiber activation chemically with a solution of H2SO4 by way of immersed in the solution for 24 hours. The best quality activated charcoal obtained from the comparison of the 75% shell, 25% palm fiber with activator H2SO4 that has a yield of 95.94%, 4.9% moisture content, ash content 6.13%, iodine number 916.594 mg / g. Activated charcoal mixture palm shell and palm fiber can be used as adsorbent liquid waste CPO, which is indicated by a decline in these parameters in the waste water contaminants in CPO, which is a 7.49 pH of 9, TSS of 660 ppm to 325 ppm,COD becomes 237,12 mg/L from1577.60 mg/L

    Degradation of epoxy coatings under gamma irradiation

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    Epoxy networks based on Diglycidyl ether of bisphenol A (DGEBA) and cured with Jeffamines (POPA) or polyamidoamine (PAA) were gamma irradiated at 25 1C in air. Dose rates of 50, 200 or 2000 Gy h- 1 for doses up 100 kGy were used. Structural changes were monitored by IR spectrophotometry, DSC and sol–gel analysis. Both networks display some common features: for I Z 200 Gy h- 1, reaction products grow proportionally to time and the rate is a decreasing function of dose rate. The simplest explanation is that peroxy radicals are the main precursors of these products (in the dose rate domain under study), through a unimolecular rearrangement of which an hypothetical mechanism is proposed. DGEBA–POPA are more reactive then DGEBA–PAA networks (according to IR criteria), that can be attributed to the high reactivity of tertiary CH bands in polyoxypropylene segments. The oxidation of these sites leads to methyl ketones. A simple kinetic model in which methyl ketones result from rearrangements of tertiary peroxyls and from tertiary alkoxyls was proposed. It leads to an expression of the radiochemical yield of methyl ketones (G(MK)) of the form GĂ°MKĂžÂŒ a ĂŸ bI-1=2 where a and b are parameters depending of elementary rate constants. Experimental G(MK) values are reasonably well ïŹtted by this equation. In DGEBA–PAA networks, a wide variety of oxidation products, among which amides predominate, can be observed. In these networks, chain scissions predominate over crosslinking, whereas a slight predominance of crosslinking was observed, at least for the lowest dose rate, in DGEBA–POPA

    Thermo-oxidative aging of epoxy coating systems

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    tThe thermo-oxidative behavior of unformulated (unfilled) samples of epoxy coatings has been studiedat five temperatures ranging from 70◩C to 150◩C. Two epoxy networks based on diglycidyl ether ofbisphenol A (DGEBA), respectively, cured by jeffamine (POPA) or polyamidoamine (PAA) were compared.Infrared spectrophotometry (IR), differential scanning (DSC) and sol–gel analysis (SGA) were used tomonitor structural changes.Thermal oxidation leads to carbonyl and amide formation in both systems. POPA systems appear moresensitive to oxidation than PAA ones. Thermal oxidation leads to predominant chain scission as evidencedby the decrease of glass transition temperatures (Tg) and increase of sol fraction
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