Single-Event Upset Analysis and Protection in High Speed Circuits

The effect of single-event transients (SETs) (at a combinational node of a design) on the system reliability is becoming a big concern for ICs manufactured using advanced technologies. An SET at a node of combinational part may cause a transient pulse at the input of a flip-flop and consequently is latched in the flip-flop and generates a soft-error. When an SET conjoined with a transition at a node along a critical path of the combinational part of a design, a transient delay fault may occur at the input of a flip-flop. On the other hand, increasing pipeline depth and using low power techniques such as multi-level power supply, and multi-threshold transistor convert almost all paths in a circuit to critical ones. Thus, studying the behavior of the SET in these kinds of circuits needs special attention. This paper studies the dynamic behavior of a circuit with massive critical paths in the presence of an SET. We also propose a novel flip-flop architecture to mitigate the effects of such SETs in combinational circuits. Furthermore, the proposed architecture can tolerant a single event upset (SEU) caused by particle strike on the internal nodes of a flip-flo

Selective gold and palladium adsorption from standard aqueous solutions

The intensive exploitation of resources on a global level has led to a progressive depletion of mineral reserves, which were proved to be insufficient to meet the high demand for high-technological devices. On the other hand, the continuous production of Waste from Electrical and Electronic Equipment (WEEE) is causing serious environmental problems, due to the complex composition of WEEE, which makes the recycling and reuse particularly challenging. The average metal content of WEEE is estimated to be around 30% and varies depending on the manufacturing period and brand of production. It contains base metals and precious metals, such as gold and palladium. The remaining 70% of WEEEs is composed of plastics, resins, and glassy materials. The recovery of metals from WEEEs is characterized by two main processes well represented by the literature: Pyrometallurgy and hydrometallurgy. Both of them require the pre-treatment of WEEEs, such as dismantling and magnetic separation of plastics. In this work, the selective adsorption of precious metals has been attempted, using copper, gold, and palladium aqueous solutions and mixtures of them. A screening on different adsorbent materials such as granular activated carbons and polymers, either as pellets or foams, has been performed. Among these, PolyEther Block Amide (PEBA) was elected as the most performing adsorbent in terms of gold selectivity over copper. Spent PEBA has been then characterized using scanning electron microscope, coupled with energy dispersive spectroscopy, demonstrating the predominant presence of gold in most analyzed sites, either in the pellet or foam form

Hepatotoxicity induced by greater celandine (Chelidonium majus L.): a review of the literature

The available literature assessing Chelidonium majus L. (CM) hepatotoxicity potential, and its risk to benefit assessment has been reviewed in this paper. Identification of significant scientific literature was performed via the following research databases: Cochrane Central, Google Scholar, EMBASE, Medline, Science Direct, Scopus, Web of Science, using the following keywords: "Chelidonium majus", "greater celandine", "Hepatotoxicity", "Liver" "Injury", "Toxicity" individually investigated and then again in association. CM named also greater celandine, swallow-wort, or bai-qu-cai (Chinese), has been used for a long time in traditional Chinese medicine and phytotherapy. Its extracts have been claimed to display a wide variety of biological activities: antimicrobial, anti-inflammatory, spasmolytic, antineoplastic, hepatoprotective, and analgesic. Moreover, herbal medicine suggests this plant have numerous additional effects which have not yet been scientifically evaluated, such as antitussive, diuretic, and eye-regenerative. However, despite its claimed hepatoprotective effects, several hepatotoxicity cases have been reported to be probably or highly probably connected with CM exposure, after their evaluation through liver-targeted causality assessment methods. CM hepatotoxicity has been defined as a distinct form of herb-induced liver injury (HILI), due to an idiosyncratic reaction of the metabolic type. This evidence has to be considered in relationship with the absence of considerable benefits of CM therapy. Therefore, the risk to benefit ratio of the use of herbal products containing greater celandine can actually be considered as negative

ATPG for Dynamic Burn-In Test in Full-Scan Circuits

Yield and reliability are two key factors affecting costs and profits in the semiconductor industry. Stress testing is a technique based on the application of higher than usual levels of stress to speed up the deterioration of electronic devices and increase yield and reliability. One of the standard industrial approaches for stress testing is high temperature burn-in. This work proposes a full-scan circuit ATPG for dynamic burn-in. The goal of the proposed ATPG approach is to generate test patterns able to force transitions into each node of a full scan circuit to guarantee a uniform distribution of the stress during the dynamic burn-in tes

Automatic March Tests Generations for Static Linked Faults in SRAMs

Static linked faults are considered an interesting class of memory faults. Their capability of influencing the behavior of other faults causes the hiding of the fault effect and makes test algorithm design a very complex task. A large number of March tests with different fault coverage have been published and some methodologies have been presented to automatically generate March tests. In this paper we present an approach to automatically generate March tests for static linked faults. The proposed approach generates better test algorithms then previous, by reducing the test lengt

Selective leaching of precious metals from electrical and electronic equipment through hydrometallurgical methods

The rapid human evolution has improved the quality of our lives through the use of technology. This not only resulted in increased raw materials extraction but also in the production of a worrying amount of electronic wastes. Indeed, in 2019 worldwide production of Electronic and Electric Equipment Waste (WEEE) was worth 50 million tons, causing several disadvantages such as the reduced space in landfills and massive shipping to countries with less restrictive regulations. On the other side, the billionaire electrical devices market is causing a significant increase in Precious Metals (PM) demand. Nowadays, the economic importance of PMs is as high as their supply risk. The answer to this problem consists of finding selective methods to extract and raffinate precious metals from disposed WEEE. On average, WEEEs contain around 30 % of plastics, 30 % ceramics, and 40 % metals; among these only around 0.1 % is characterized by PMs, such as gold, silver, rhodium, platinum, and palladium. The separation of PMs from other non-precious components is generally obtained using pyrometallurgy, which consists of fusing the wastes at temperatures up to 1500 ÷ 1700 °C. However, this method produces toxic gaseous byproducts and implies high energy costs. A possible alternative is given by hydrometallurgical processes, consisting of leaching the WEEE with solutions containing acids and oxidants at temperatures lower than 100°C. One of the main issues of the hydrometallurgical process is to leach copper and other non-precious base-metals selectively while keeping PMs in the solid-state. In this work, we report preliminary results of equilibrium and kinetic leaching tests in a well-stirred batch reactor, aimed at the optimization of the main operating parameters of a hydrometallurgical process for selective leaching of copper and other base-metals from Wasted Printed Circuit Boards (WPCBs). In particular, experiments have been carried out at different HCl and NaCl concentrations of the leaching solutions, exploring also the effect of temperature variation (20, 50, and 70 °C)

PROMON: a profile monitor of software applications

Software techniques can be efficiently used to increase the dependability of safety-critical applications. Many approaches are based on information redundancy to prevent data and code corruption during the software execution. This paper presents PROMON, a C++ library that exploits a new methodology based on the concept of “Programming by Contract” to detect system malfunctions. Resorting to assertions, pre- and post-conditions, and marginal programmer interventions, PROMON-based applications can reach high level of dependability

Spectral Evolution of Scorpio X-1 along its Color-Color Diagram

We analyze a large collection of RXTE archive data of the bright X-ray source Scorpius X-1 in order to study the broadband spectral evolution of the source for different values of the inferred mass accretion rate by selecting energy spectra from its Color-Color Diagram. We model the spectra with the combination of two absorbed components: a soft thermal component, which can be interpreted as thermal emission from an accretion disk, and a hybrid Comptonization component, which self-consistently includes the Fe Kα fluorescence line and the Compton reflected continuum. The presence of hard emission in Scorpius X-1 has been previously reported, however, without a clear relation with the accretion rate. We show, for the first time, that there exists a common trend in the spectral evolution of the source, where the spectral parameters change in correlation with the position of the source in the CD. Using a hybrid thermal/non-thermal Comptonization model (EQPAIR code), we show that the ratio of the power supplied to the non-thermal distribution to the total power injected into the Comptonizing plasma correlates with the accretion rate, being the highest at the lowest accretion rates. We discuss the physical implications derived from the results of our analysis, with a particular emphasis on the hardest part of the X-ray emission and its possible origin

Energy and Environmental Performance Comparison of Heat Pump Systems Working with Alternative Refrigerants

Featured Application: An energy and environmental performance analysis of air-source and ground-source heat pump systems able to operate with traditional (R-410A) and alternative low-GWP (R-454B) refrigerants is conducted. The case study is composed of an existing residential single-family house, and the coupled HVAC system is modeled by means of the commercial software TRNSYS. The TEWI index is considered to evaluate the environmental impact of the heat pump systems. The results of the numerical simulations show a significant reduction in the overall greenhouse emissions of those systems in which R-454B is employed as a refrigerant. The European Parliament has imposed to reduce by 2030 whole HFC emissions by at least two-thirds with respect to 2014 levels. With the aim of contributing to determine the energy and environmental advantages of refrigerants alternative to R-410A, this paper reports the results of a numerical study focused on an HVAC system coupled to a residential building and based on a reversible electric heat pump. In particular, two heat pump typologies are considered: an air-source and a ground-source heat pump, both operating with the two refrigerants R-410A and R-454B. The environmental performance of the studied system is assessed by means of the TEWI (total equivalent warming impact) index. The adoption of R-454B involves a slight decrease (2–3%) in the overall annual energy performance of the system with respect to the use of R-410A. On the other hand, the working fluid R-454B guarantees a marked decrease in the TEWI indicator. Indeed, considering the current Italian emission factor of electricity taken from the grid, the total emissions over the entire heat pump operating life drop by about 25% and can decrease by up to 89% in perspective, following the current reduction trend of the emission factor

A Rapid Detection of Meat Spoilage using an Electronic Nose and Fuzzy-Wavelet systems

Freshness and safety of muscle foods are generally considered as the most important parameters for the food industry. To address the rapid detection of meat spoilage microorganisms during aerobic or modified atmosphere storage, an electronic nose with the aid of fuzzy wavelet network has been considered in this research. The proposed model incorporates a clustering pre-processing stage for the definition of fuzzy rules. The dual purpose of the proposed modelling approach is not only to classify beef samples in the respective quality class (i.e. fresh, semi-fresh and spoiled), but also to predict their associated microbiological population directly from volatile compounds fingerprints. Comparison results against neural networks and neurofuzzy systems indicated that the proposed modelling scheme could be considered as a valuable detection methodology in food microbiolog