ISA implementation and uncertainty: A literature review and expert elicitation study

Each day, an average of over 116 people die from traffic accidents in the European Union. One out of three fatalities is estimated to be the result of speeding. The current state of technology makes it possible to make speeding more difficult, or even impossible, by placing intelligent speed limiters (so called ISA devices) in vehicles. Although the ISA technology has been available for some years now, and reducing the number of road traffic fatalities and injuries has been high on the European political agenda, implementation still seems to be far away. Experts indicate that there are still too many uncertainties surrounding ISA implementation, and dealing with these uncertainties is essential for implementing ISA. In this paper, a systematic and representative inventory of the uncertainties is made based upon the literature. Furthermore, experts in the field of ISA were surveyed and asked which uncertainties are barriers for ISA implementation, and how uncertain these uncertainties are. We found that the long-term effects and the effects of large-scale implementation of ISA are still uncertain and are the most important barriers for the implementation of the most effective types of ISA. One way to deal with these uncertainties would be to start implementation on a small scale and gradually expand the penetration, in order to learn how ISA influences the transport system over time.     

Quantifying reliability uncertainty from catastrophic and margin defects: A proof of concept

We aim to analyze the effects of component level reliability data, including both catastrophic failures and margin failures, on system level reliability. While much work has been done to analyze margins and uncertainties at the component level, a gap exists in relating this component level analysis to the system level. We apply methodologies for aggregating uncertainty from component level data to quantify overall system uncertainty. We explore three approaches towards this goal, the classical Method of Moments (MOM), Bayesian, and Bootstrap methods. These three approaches are used to quantify the uncertainty in reliability for a system of mixed series and parallel components for which both pass/fail and continuous margin data are available. This paper provides proof of concept that uncertainty quantification methods can be constructed and applied to system reliability problems. In addition, application of these methods demonstrates that the results from the three fundamentally different approaches can be quite comparable.     

Enhancing the dewaterability of anaerobically digested sludge using fibrous materials recovered from primary sludge: demonstration from a field study

Clean Technologies and Environmental Policy - Sludge dewatering is an important process for determining the operation cost of sludge disposal. Hence, improving the dewaterability of anaerobically...     

Identifying emerging technologies using expert opinions on the future: A topic modeling and fuzzy clustering approach

Scientometrics - As technology rapidly advances with the Fourth Industrial Revolution, many emerging technologies have been developed in several technology sectors. These technologies can (1)...     

Mining knowledge from text repositories using information extraction: A review

There are two approaches to mining text form online repositories. First, when the knowledge to be discovered is expressed directly in the documents to be mined, Information Extraction (IE) alone can serve as an effective tool for such text mining. Second, when the documents contain concrete data in unstructured form rather than abstract knowledge, Information Extraction (IE) can be used to first transform the unstructured data in the document corpus into a structured database, and then use some state-of-the-art data mining algorithms/tools to identify abstract patterns in this extracted data. This paper presents the review of several methods related to these two approaches.     

Low-cost disordered carbons for Li/S batteries: A high-performance carbon with dual porosity derived from cherry pits

A micro- and mesoporous carbon obtained from cherry pit waste and activated with H₃PO₄ acid has been studied as the sulfur host for Li/S batteries. The carbon has a high specific surface area of 1,662 m²·g^–1 (SBET) and micropore and mesopore volumes of 0.57 and 0.40 cm³·g^–1, respectively. The S/C composite, with a sulfur content of 57% deposited by the disproportionate reaction of a S₂O₃ ^2? solution in an acid medium without an additional heating step above the S melting point, delivers an initial specific capacity of 1,148 mAh·g^–1 at a current of C/16. It also has a high capacity retention of 915 mAh·g^–1 after 100 cycles and a Coulombic efficiency close to 100%. The good performance of the composite was also observed under higher current rates and long-term cycling tests. The capacities delivered by the cell after 200 cycles were 707 and 410 mAh·g^–1 at C/2 and 1C (1C = 1,675 mA·g^–1), respectively, maintaining the high Coulombic efficiency. The overall electrochemical response of this carbon as the sulfur matrix is among the best reported so far among the other biomass-derived carbons, probably because of the micro- and mesopore system formed upon activation.

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A Novel near white light emitting nanocrystalline Zn2P2O7:Sm3+ derived using citrate precursor route: Photoluminescence spectroscopy

Nanocrystalline Zn₂P₂O₇:Sm³⁺ was synthesized using citrate precursor route. Rietveld refined XRD shown the formation of pure phase at 900 °C. Based on scanning electron microscopy, size distribution of the pyrophosphate particle was found to be in the range of 50–100 nm. Upon near UV light excitation (403 nm), Zn₂P₂O₇:Sm³⁺exhibits host emission at 450 nm along with characteristic emission lines of Sm³⁺. Based on PL decay measurement, it was inferred that two different types of Sm³⁺ ions were present in the zinc pyrophosphate. The first type was a short lived species (∼τ = 100 μs) present at less symmetric ‘5-coordinated Zn’ sites, while the second was a long lived species (∼τ = 1.9 ms) present at symmetric ‘6-coordinated Zn’ sites. The color coordinates of the system were evaluated using CIE index diagram to be 0.36 and 0.37, which suggest that the prepared material is a potential near white light emitting phosphor.     

Highly stable MAPbI3 microcrystals: a single precursor derived from low-grade PbI2 using sono-chemical method for economical and efficient perovskite solar cells

Journal of Materials Science: Materials in Electronics - The remarkable performance of organometallic lead halide perovskites in solar cell technology has drawn attention due to their intriguing...     

A study on sampling methods for chloride profiles: simulations using data from EPMA

Investigating marine concrete by determining the chloride profile is a common way for making a prediction of the remaining service life of a structure. The most common methods of sampling concrete for this purpose is dust sampling by dry drilling or sampling cores which are analyzed by profile grinding in a laboratory. Now, a similar study has been performed, by simulating different sampling techniques in data from EPMA. The results from the simulations of the concrete specimen analyzed with the EPMA, confirm the results from earlier performed dry drilling tests in laboratory and shows the same extensive variations when chloride content is presented as % by weight of concrete instead of as % by weight of calcium oxide. Comparing the results from the earlier performed sampling by dry drilling with the results from the EPMA simulations, it is seen that the dry drilling probably is afflicted with a systematic error by “movement” of dust into the sampling holes when drilling. This study also shows effects of large aggregates in small bores even though the cement content is referred to. However, no signs of “shadowing” by the aggregates was detected when the simulations where performed. Even “horizontal” drilling was simulated in order to be able to detect this possible effect of the aggregates on the chloride ingress into the concrete.     

A blood oxygenator from indigenous materials: Functional evaluation using sheep lung as deoxygenator

In vitro evaluation of an oxygenator is an integral part of its development. In order to obtain meaningful data the test conditions must be standardised. The natural lung offers a large surface area for gas exchange and provides excellent oxygenation over wide range of blood flows. Consequently it should act as a good deoxygenator too. Our experience in using a sheep lung for deoxygenation is described.     

Porous SiO2 interferometric biosensor for quantitative determination of protein interactions: binding of protein A to immunoglobulins derived from different species

Determination of kinetic and thermodynamic protein binding constants using interferometry from a porous Si Fabry-Perot layer is presented. A protein A capture probe is adsorbed within the pores of an oxidized porous Si matrix, and binding of immunoglobulin G (IgG) antibodies derived from different species is investigated. The relative protein A/IgG binding affinity is human > rabbit > goat, in agreement with literature values. The equilibrium binding constant (Ka) for human IgG binding to surface-immobilized protein A is determined to be (3.0 +/- 0.5) x 107 M-1 using an equilibrium Langmuir model. Kinetic rate constants are calculated to be kd = (2.1 +/- 0.2) x 10-4 s-1 and ka = (1.2 +/- 0.4) x 104 M-1 s-1 using nonlinear least-squares analysis, yielding an equilibrium binding constant of Ka = (5.5 +/- 1.5) x 107 M-1. Both steady-state and time-dependent measurements yield equilibrium binding constants that are consistent with literature values. Kinetic rate constants determined through nonlinear least-squares analysis are also in agreement with protein A/IgG binding on a surface. Dosing with a high concentration of analyte leads to deviations from ideal binding behavior, interpreted in terms of restricted analyte diffusion within the porous SiO2 matrix. It is shown that the diffusion limitations can be minimized if the kinetic measurements are performed at low analyte concentrations or under conditions in which the protein A capture probe is not saturated with analyte. Potential limitations of the use of porous SiO2 interferometers for quantitative determination of protein binding constants are discussed.     

A gel-forming poly-l-guluronic acid produced from no guluronate-rich marine algae using new hydrolysis method: test for endovascular embolization

To prepare a gel-forming poly-l-guluronic acid (Poly-G) from no guluronate-rich Laminaria japonica, a new hydrolysis method was employed with a lower HCl concentration (0.025–0.15 M) and a shorter treatment time (5 min). The Poly-Gs were set to measure purity, presence of poly-l-guluronic block, molecular weight distribution, polymer yield, viscosity, and compressive gel strength. Finally, the Poly-G was tested to embolize the renal vascular system by using a rabbit model and angiography. Optimized Poly-G could be selected with respect to wt% concentration, polymer yield, gel-forming stability, viscosity, and gel strength as an endovascular embolizing agent. Overall, 0.4–0.6% of 0.03 M-Poly-G obtained from acid treatment with 0.03 M of HCl had molecular weights greater than 80 kDa, and the best gelling capacity with an injectable viscosity (30–120 cP). It was successfully delivered into the vascular bed of a rabbit kidney and was shown angiographically to embolize the renal vascular system.     

Recognizing features from engineering drawings without using hidden lines: A framework to link feature recognition and inspection systems

Many two-dimensional (2D) feature recognition systems have recently been developed to salvage the massive store of engineering knowledge in 2D form and bring the benefit of computer-aided design (CAD)-computer-aided manufacturing (CAM) integration to 2D CAD users. However, the significant amount of effort spent in developing these systems has little use in the related field of 'Automated Visual Inspection' (AVI). This is because there are some differences in the formats of input to feature recognition and AVI systems with respect to hidden feature information. This paper presents a method to extract feature information from 2D drawings without using hidden lines. This is an initial step towards establishing a common input format between AVI and feature recognition systems, and in turn a common framework to link them. The absence of hidden edges in photographic and video images, which are used as input to the AVI systems, is mimicked by not using hidden lines, although they are normally available in any drawing. However, the lack of hidden line information is compensated for by isometric projections, which are of the same format as that of the photographic input to AVI systems. The ability to recognize features from orthographic projections coupled with isometric views but without hidden lines will be directly transferable to AVI systems, which will have a substantial impact on automatic inspection, reverse modelling and manufacturing automation and, in turn, on manufacturing productivity.     

Cell-protecting regeneration from anode carbon deposition using in situ produced oxygen and steam: A combined experimental and theoretical study

Carbon deposition is a primary concern during the operation of solid oxide fuel cells (SOFCs) fueled with hydrocarbon fuels, leading to cell degradation and even cell damage. Carbon elimination is expected to be a promising approach to prolong cell life. This work reports on a combined experimental and theoretical investigation of cell regeneration from anode carbon deposition of tubular SOFCs fabricated by phase-inversion and co-sintering techniques. The as-prepared cell exhibits a maximum power density of 0.20?W?cm^?2 at 800?°C fueling with wet CH₄, but fails to stable operation due to severe carbon deposition. Based on thermodynamic predictions, a successive cell-protecting regeneration process is proposed to eliminate deposited carbon without oxidizing Ni catalysts, during which CH₄ and H₂ fuels are provided in circulation. Through a total of 35 cycling tests, cell performance can always successfully restore to the initial level. The possible carbon elimination mechanism is investigated in detail based on thermodynamic and first-principle calculations. The feasibility of carbon elimination using in situ produced oxygen or steam through electrochemical reaction has been revealed, providing a novel continuous operation mode for hydrocarbon-based SOFCs.     

Biosorption of cadmium (II) and lead (II) from aqueous solutions using mushrooms: A comparative study

Sorption capacity of oyster mushroom (Pleurotus platypus), button mushroom (Agaricus bisporus) and milky mushroom (Calocybe indica) were evaluated on biosorption of heavy metals, viz. cadmium (II) and lead (II) from aqueous solutions. The optimum sorption conditions were studied for each metal separately. The desired pH of the aqueous solution was found to be 6.0 for the removal of cadmium (II) and 5.0 for removal of lead (II) for all the mushrooms. The percent removal of both the metals was found to increase with the increase in biosorbent dosage and contact time. The fitness of the biosorption data for Langmuir and Freundlich adsorption models was investigated. It was found that biosorption of cadmium (II) and lead (II) ions onto the biomass of the three mushrooms were better suitable to Langmuir than Freundlich adsorption model. P. platypus showed the highest metal uptake potential for cadmium (q_max 34.96 mg/g) whereas A. bisporus exhibited maximum potential for lead (q_max 33.78 mg/g). Milky mushroom showed the lowest metal uptake capacity for both the metals. The present data confirms that mushrooms may be used as efficient biosorbent for the removal of cadmium (II) and lead (II) ions from aqueous solution.     

Mitigation of effects of pulsed heat load from fusion devices on helium refrigerator: A novel technique using vapor compression cycle

Helium refrigerators used in fusion devices are subjected to pulsed heat load. Immediate effect of such load is high fluctuation of mass flow rate at the return stream. A novel technique using vapor compression cycle at the cold end of helium refrigerators has been proposed to mitigate this flow fluctuation. The concept behind the proposed scheme is to re-liquefy excess return stream during high heat load condition and store. During low heat load condition, mitigation is obtained by increasing vapor fraction after expansion in JT valves by increasing inlet temperature of these valves. Dynamic simulation of a plant modified with vapor compression cycle has been performed and it has been found that approximately 70% and 96% mitigation of flow fluctuation during high and low heat load respectively, can be achieved. Criteria of selection and technical feasibility of critical equipment for implementation of the concept have also been discussed.