Computational efficiency of the continuous cell-to-cell mapping technique as a function of integration schemes

The continuous cell-to-cell mapping technique (CCCMT) is a recently proposed Markovian approach which can be used for the dynamic reliability and safety analysis of process control systems, as well as for the global analysis of nonlinear dynamic systems in general. A parametric study is performed on the computational efficiency of CCCMT as a function of various integration schemes. The results show that a variable stepsize scheme is desirable with a sufficient required precision. Among the integration schemes considered, a fourth order Runge-Kutta scheme seems to be preferable for short term simulations and the mid-point implicit scheme seems to be preferable for long term simulations or to obtain the steady-state system behavior.     

Effects of cognitive load on semantic priming in patients with schizophrenia.

Schizophrenic and control participants received 2 blocks of trials in each experiment. In 1 block they were exposed to regular priming trials (doctor–nurse), and in another block a nonlexical probe was presented at prime onset for 40 ms. Regardless of stimulus onset asynchrony (SOA), the schizophrenic patients showed hyperpriming when no distractor was present. Paying attention to the distracting stimulus reduced priming in the patient group irrespective of SOA. Under certain situations, the reduction in priming appeared even when participants were asked to ignore the distracting stimulus. Thus, even a nonsemantic distractor may be detrimental to schizophrenic patients' language processing. That SOA did not modulate the reduction in priming effect is consistent with the suggestion that attentional resources are required even with short prime–target intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Polymeric Nanocomposites (PNCs) for Wastewater Remediation: An Overview

A decline in the world’s freshwater resources poses a major domestic and industrial challenge. Amelioration efforts that proffer possible water management and reclamation technology is therefore, of utmost priority. One of the most promising solutions to water conservation is to recycle wastewater. The use of polymeric nanocomposites (PNCs) in water treatment/remediation processes provides possible solution to recycling. This overview focused on PNCs; to highlight trends in their fabrication, characterization and application procedures for wastewater remediation and monitoring. Key issues bothering on the regeneration and reuse of PNCs were discussed, along with projections for their rational design for safe application.     

Detection of X‐Rays by Solution‐Processed Cesium‐Containing Mixed Triple Cation Perovskite Thin Films

Materials and technology development for designing innovative and efficient X‐ray radiation detectors is of utmost importance for a wide range of applications ranging from security to medical imaging. Here, highly sensitive direct X‐ray detectors based on novel cesium (Cs)‐based triple cation mixed halide perovskite thin films are reported. Despite being in a thin film form, the devices exhibit a remarkably high X‐ray sensitivity of (3.7 ± 0.1) µC Gy^?1 cm^?2 under short‐circuit conditions. At a small reverse bias of 0.4 V, the sensitivity further increases by orders of magnitude reaching a record value of (97 ± 1) µC Gy^?1 cm^?2 which surpasses state‐of‐the‐art inorganic large‐area detectors (a‐Se and poly‐CZT). Based on detailed structural, electrical, and spectroscopic investigations, the exceptional sensitivity of the triple cation Cs perovskite is attributed to its high ambipolar mobility‐lifetime product as well as to the formation of a pure stable perovskite phase with a low degree of energetic disorder, due to an efficient solution‐based alloying of individual n‐ and p‐type perovskite semiconductors.     

Spiro‐Bridged Ladder‐Type Oligo(para‐phenylene)s: Fine Tuning Solid State Structure and Optical Properties

A set of ladder‐type quaterphenyls with an incremental number of spiro‐bifluorene units in the bridge positions as well as an in‐plane bent quaterphenyl carrying all bridges on one and the same side of the ribbon are synthesized and characterized. While spiro‐bifluorene substituents lead to bathochromically shifted maxima in the UV–vis absorption spectra, this effect can be compensated by in‐plane bending. The influence of different deposition techniques on the solid state structure is analyzed by X‐ray diffraction of single crystals obtained by crystallization from solution as well as sublimation. An increasing number of spiro‐bifluorene substituents are found to aid thin‐film formation.     

Illegal unregulated and unreported fishing: Methods and increasing trends in Lake Naivasha,Kenya

Illegal, unregulated and unreported (IUU) fishing is a negative social vice that adversely affects global capture fishery production. The inadequate disclosure of IUU methods and trends in fishery waters hampers management actions to curb illegal fishing activities. Seldom have empirical studies been conducted on IUU methods and their trends in Lake Naivasha. Therefore, this study analysed data on the fisheries monitoring, control and surveillance (MCS) during 2012 to 2018 to test for the significance of trends, and compare the enforcement plans to seizures of illegal fishing gear in the lake. The IUU fishing methods included both the types of equipment and the means used to perpetrate illicit capture or acquisition of fish from the lake. The results indicate a 37% reduction of MCS enforcement patrols during 2018 compared to 2012, and a 16% to 100% upsurge in the quantity of seized IUU fishing items. Illegal fishing boats potentially threaten the fishery of Lake Naivasha with an additional fishing effort of 22% above the 176 licensed boats. An average of 10,700 fishing nets seized per year has the potential fishing intensity of 74 gillnets/km² against an ideal intensity of 12 gillnets/km². The frequencies of MCS patrols in Lake Naivasha exhibit no particular trends and likely ineffective in deterring the upsurge of IUU activities, or the evolution of new illegal fishing methods. An increased seizure of illegal fishing boats, outboard engines and gillnets could imply their rampant use in IUU fishing activities. These findings merit a multi‐stakeholder participatory approach to identifying the MCS weaknesses and opportunities for sharing resources to strengthen the fishery management efforts in Lake Naivasha.     

Association behavior of thermo-responsive block copolymers based on poly(vinyl ethers)

Thermo-sensitive nanosized structures have been prepared in water from poly(methyl vinyl ether)-block-poly(isobutyl vinyl ether) (PMVE-b-PIBVE) block copolymers. The composition and the architecture (diblock and triblock architectures) of the PMVE-b-PIBVE copolymers have been varied. The investigated copolymers had an asymmetric composition with a major PMVE block. While the PIBVE blocks are hydrophobic, the PMVE blocks are hydrophilic at room temperature and become hydrophobic above their demixing temperature (around 36 °C) as a result of the lower critical solution temperature (LCST) behavior. At room temperature, the amphiphilic copolymers aggregate in water above a critical micelle concentration, which has been experimentally measured by hydrophobic dye solubilization. The hydrodynamic diameter of the structures formed above the cmc has been measured by dynamic light scattering (DLS) while their morphology has been studied by transmission electron microscopy (TEM). ¹H NMR measurements in D₂O at room temperature reveal that the aggregates contain PIBVE insoluble regions surrounded by solvated PMVE chains. These investigations have shown that polydisperse spherical micelles are formed for asymmetric PMVE-b-PIBVE copolymers containing at least 9 IBVE units. For copolymers containing less IBVE units, loose aggregates are formed.Finally, the thermo-responsive, reversible properties of these structures have been investigated. Above the cloud point of the copolymers, the loose aggregates precipitate while the micelles form large spherical structures.     

Classifier ensembles to improve the robustness to noise of bearing fault diagnosis

In this paper, we perform a noise analysis to assess the degree of robustness to noise of a neural classifier aimed at performing multi-class diagnosis of rolling element bearings. We work on vibration signals collected by means of two accelerometers and we consider ten levels of noise, each of which characterized by a different signal-to-noise ratio ranging from 40.55 to ?11.35 db. We classify the noisy signals by means of a neural classifier initially trained on signals without noise and then we repeat the training process with signals affected by increasing levels of noise. We show that adding noisy signals to the training set we can significantly increase the classification accuracy of a single classifier. Finally, we apply the two most used strategies to combine classifiers: classifier fusion and classifier selection, and show that, in both cases, we can significantly increase the performance of the single best classifier. In particular, classifier selection achieves the best results for low and medium levels of noise, while classifier fusion is the most accurate for high levels of noise. The analysis presented in the paper can be profitably used to identify both the type of classifier (e.g., single classifier or classifier ensemble) and how many and which noise levels should be used in the training phase in order to achieve the desired classification accuracy in the application domain of interest.     

Inflated structures : Air-springs and floats

A comprehensive analysis of the characteristics (load and deformation, etc.) of structures consisting of an inextensible tubular envelope filled with a gas, compressed between two rigid surfaces or between a rigid surface and a liquid or pulled down into a liquid by a weight is presented. Such structures can be used as springs or floats. Numerical results, given in a dimensionless graphical form, can be used for engineering design purposes. This analysis of a simple tubular structure can serve as a basis for the study of the behaviour of structures of more complicated shapes.