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Date palm fruits (Phoenix dactylifera) contain a significant amount of carbohydrates with substantial nutritional content, making them an alternative source of sugar for diabetic patients. In this study, the effect of moderate electric field (MEF) on the extraction of soluble sugars from date fruit powder (DFP) was investigated. MEF treatments were performed in a custom-designed batch reactor by applying a constant electric field strength (EF) of 10 V/cm across the platinized coated titanium electrodes (surface area = 2 cm2) using a frequency generator. The operating conditions were optimized by varying the extraction time (5, 10, 20, 30, and 60 min), applied frequency (20–100 Hz with 20 units difference), and operating temperature (25 to 65 ± 2 °C with a difference of 10°). The soluble sugar was also hauled out by processing the DFP with the conventional hot-water extraction (CHW) technique. The MEF-based extraction technique resulted in an increased sugar yield of 74.5%, which is 14% more than the total sugar yield obtained by the CHW method. Low frequencies (40 Hz), optimized time (30 min), and high temperatures (55 °C) resulted in higher extraction yields for DFP. In addition, a microscopic examination of MEF residues was performed to analyze the effect of electric field on the pore formation and surface rupturing of DFP during soluble sugar extraction. The MEF extraction technique showed higher sugar extraction yield due to electroporation and permeabilization, which enables improved diffusion and has the potential to be effectively used for juice extraction compared to the conventional energy-intensive and advanced extraction methods. [ABSTRACT FROM AUTHOR]

The cognitive ability of older adults declines with age, while the language processing experience becomes more abundant. Word recognition is one of the most fundamental abilities in language processing, but how the interaction of cognitive aging and language experience affects word recognition in older adults is still a complex issue. This study focuses on the influence of two factors, age of acquisition (AoA) and parts of speech on Chinese word recognition in older adults. In Experiment 1, we employed a context-free lexical decisions task to compare the differences of word recognition between young and older adults at the conditions of different AoAs and parts of speech. In Experiment 2, participants were required to perform a sentence reading task in order to examine the above effects with contextual involvement, and their eye movements were tracked and analyzed. Combining the results of the two experiments, we found a greater AoA effect in older adults compared to young adults. This effect primarily manifested as a decline in processing efficiency for late-acquired words and was already evident in the early stage of word recognition. In addition, only the older adults exhibit differences in the processing of distinct word components, indicating a progressive pattern of increasing difficulty from nouns to verbs and subsequently to adjectives. The findings suggest that older adults experience a heightened exacerbation of word processing difficulties. [ABSTRACT FROM AUTHOR]

Gasoline engine vehicle emissions, such as nitrogen oxides (NOx), CO and hydrocarbons (HCs), are a major source of air pollution, and require improved emission control systems. By-product NH3 and N2O emissions, which come from low N2 selectivity in the emission control system, are also a major concern. The current study has comprehensively investigated the impact of the Pt-substitution in commercial Pd/Rh-based three-way catalyst (TWC) formulations with respect to catalytic performance. TWC performance was systematically evaluated with respect to the warm-up catalytic converter (WCC) and the under-floor catalytic converter (UCC). This included evaluating TWC activity under realistic simulated exhaust conditions including fuel-rich, stoichiometric and fuel-lean (0.99≤λ≤1.01). Pt-substituted TWCs outperformed Pd-based counterparts, regardless of the converter type (WCC or UCC), in CO, C3H6 and C3H8 oxidation and NO reduction reactions under the simulated exhaust conditions tested. Moreover, Pt-substituted TWCs exhibited significant stability upon hydrothermal aging at 1,050 °C. The results show that after aging the Pt-substituted catalyst retained higher N2 selectivity than the Pd-based TWC. Over Pd-based TWCs, N2 selectivity drastically dropped from 70–80% to 15–35% after aging, while Pt-substituted TWCs N2 selectivity dropped from 80–100% to only 60–80%. The key finding from this study is that Pt incorporation in a Pd/Rh TWC improves the emission control from gasoline vehicles in terms of both CO and HC oxidation and NOx reduction. [ABSTRACT FROM AUTHOR]

Lead-free (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNT-6BT) films are deposited on Pt(111)/Ti/SiO2/Si(100) substrates for various thicknesses by pulsed laser deposition. The effects of thickness on the microstructure, Raman spectra, dielectric behavior, and ferroelectric properties are investigated in detail. The BNT-6BT films with a polycrystalline structure, as well as an increase in grain size and crystallinity, a decrease in strain, and the appearance of columnar crystals with increasing film thickness are confirmed by x-ray diffraction and field emission scanning electron microscopy. Obvious aging behavior with an abnormal double-butterfly shape of dielectric constant–electric field curves is observed in aged BNT-6BT films. Both the dielectric tunability and dielectric constant increase with increasing film thickness, with 950 nm film exhibiting the highest dielectric tunability of 36.7% and dielectric constant and loss of 572 and 0.032 at 1 kHz, respectively. Moreover, an increase in the maximum polarization (Pmax) and remanent polarization (Pr) with the increase in film thickness is also observed. The enhanced dielectric and ferroelectric properties of BNT-6BT films are strongly depended on thickness, which suggest the potential application of BNT-6BT films in film tunable capacitors. [ABSTRACT FROM AUTHOR]

The conventional Arrhenius equation that estimates the heat generation of coal in numerical simulation has been widely applied. However, the aging effect markedly influences the exothermic behavior of coal at low temperature and cannot be achieved using the conventional Arrhenius equation. In this paper, an improved wire-mesh basket test was performed to measure the temperature and concentrations of CO and CO2 emitted from coal piles. The aging effect model based on the theory of equivalent oxidation exposure time successfully matched the experimental results. Then, a two-dimensional (2D) multifield coupling model of coal stockpiles was developed considering the aging effect to investigate the developments on values and moving paths of temperature and O2 concentration. Effects of decay-power factor, which determines the diminishing coal oxidation, and other main variables on spontaneous combustion of coal stockpiles were systematically investigated. The results indicated a unique critical value of 1.25 × 10–6 s−1 for decay-power factor. Increasing decay-power factor enlarged the safe storage time and hardly affected the moving paths of the hotspot. There are two critical values for particle size (0.7 mm, 9 mm) and porosity (0.18, 0.58), and one critical value for wind velocity (8.5 m s−1) and stockpile width (9 m). Porosity and stockpile width have significant effects on the self-ignition of coal stockpiles when their values are lower than the base ones (0.33 and 15 m). The model considering aging effect is expected to reliably predict the spontaneous combustion of coal stockpile and become the tool for inspecting the reasonability of the relative preventing measures. [ABSTRACT FROM AUTHOR]

Liquefaction damage from earthquakes frequently indicates effects of sand aging on liquefaction resistance: Liquefaction damage in natural or aged reclaimed ground has been much less than that in young reclaimed ground. However, the mechanisms underlying aging effects remain unclear. Cementation and stress history of sand strongly influence aging effects: Cementation raises liquefaction resistance, whereas liquefaction history sometimes reduces liquefaction resistance. Small cyclic shear strain, from which the induced density change is almost negligible, was adopted as representing the stress history. To evaluate liquefaction resistance, initial shear modulus, and deformation characteristics of sand, we prepared specimens by adding cement and by applying a small cyclic shear strain. In cementitious sand, liquefaction resistance increased when cement contents exceeded 0.3% by mass. The initial shear modulus apparently increased at the same degree of cement addition as that which increased the liquefaction resistance. For sand with a small cyclic shear strain, the liquefaction resistance increased when the applied cyclic axial strain exceeded 0.01%. Application of small cyclic shear strain only slightly increased the initial shear modulus, but the linear elastic region tended to expand to greater shear strain. Shear properties of sand with small cyclic shear strain resembled those found for sand that had been consolidated for a long time. [ABSTRACT FROM AUTHOR]

The long-term (more than 20 years) aging effect and degradation study of a Y1-xCaxSrBaCu2.80BO30.20Oy\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\left[{{\text{Y}}}_{1\;-\;x}{{\text{Ca}}}_{x}\right]{{\text{SrBaCu}}}_{2.80}{\left({{\text{BO}}}_{3}\right)}_{0.20}{{\text{O}}}_{y}$$\end{document} powder ceramic superconductors with 0.10≤x≤0.50\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$0.10\;\le\;x\;\le\;0.50$$\end{document} are studied by X-ray diffraction and DC Magnetic Property Measurement System (DC-MPMS-SQUID). The samples prepared by solid state reaction were well characterized and stored at normal conditions of pressure and temperature for more than 20 years. The aged samples present the formation of BaCO3 due to the exposure with the environment during that period. The temperature dependence of the magnetization under Hext = 10 Oe reveal that the superconducting state remains in the samples, except for that with x = 0.10, where a higher magnetic field (20 kOe) is required to be applied to observe a superconducting response. Remarkably, the samples show the same TC values despite the aging indicating that the magnetic alignment of the formed BaCO3 affects the magnetic propertied of the whole sample but not the superconducting alignment of the doped YBCO. This is also reflected in the χ-1(T)\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${\chi }^{-1}({\text{T}})$$\end{document} plots at normal state, which show both ferromagnetic and antiferromagnetic contribution, in contrast to what was obtained in the pristine samples which only presented antiferromagnetic coupling. From M(H) loops, the critical current density values at 10 K are obtained by using the critical Bean model in order to estimate the transport capabilities of the aged powders. [ABSTRACT FROM AUTHOR]

The study of citation networks is of interest to the scientific community. However, the underlying mechanism driving individual citation behavior remains imperfectly understood, despite the recent proliferation of quantitative research methods. Traditional network models normally use graph theory to consider articles as nodes and citations as pairwise relationships between them. In this paper, we propose an alternative evolutionary model based on hypergraph theory in which one hyperedge can have an arbitrary number of nodes, combined with an aging effect to reflect the temporal dynamics of scientific citation behavior. Both theoretical approximate solution and simulation analysis of the model are developed and validated using two benchmark datasets from different disciplines, i.e. publications of the American Physical Society (APS) and the Digital Bibliography & Library Project (DBLP). Further analysis indicates that the attraction of early publications will decay exponentially. Moreover, the experimental results show that the aging effect indeed has a significant influence on the description of collective citation patterns. Shedding light on the complex dynamics driving these mechanisms facilitates the understanding of the laws governing scientific evolution and the quantitative evaluation of scientific outputs. [ABSTRACT FROM AUTHOR]

This paper investigates a competitive two-agent parallel-batching scheduling problem with aging effect on parallel machines. The objective is to minimize the makespan of agent A with the constraint that the makespan of agent B is no more than a given threshold. Some key structural properties are first identified in two different cases, and based on these structural properties a novel decision tree of scheduling rules is constructed and a heuristic algorithm is designed. Then, an effective hybrid BF-VNS algorithm combining Bacterial Foraging (BF) with variable neighborhood search (VNS) is developed to tackle the studied problem. Computational experiments are conducted to evaluate the performance of the proposed hybrid algorithm and some other well-known algorithms. The experimental results indicate that the hybrid BF-VNS algorithm performs quite better than the compared algorithms. [ABSTRACT FROM AUTHOR]

The present paper demonstrates the effect of humidity on the (Ge11.5Te12.5Se67.5)80Sb20 and (Ge11.5 Te12.5Se67.5)70Sb30 thin film deposited on a glass substrate. The films prepared using a thermal evaporation technique reveal an amorphous nature as observed from the x-ray diffraction (XRD) graph. The light absorption taking place in the UV-visible region was confirmed using a UV–Vis spectrophotometer, and optical bandgap values of 1.46 eV and 1.42 eV were found for (Ge11.5Te12.5Se67.5)80Sb20 and (Ge11.5 Te12.5Se67.5)70Sb30 alloys using Tauc's plot. The films were investigated for an impedance-based electrical humidity sensor. The maximum sensitivity of the chalcogenide sensing element was 13.86 MΩ/%RH and 15.31 MΩ/%RH for (Ge11.5Te12.5Se67.5)80Sb20 and (Ge11.5 Te12.5Se67.5)70Sb30, respectively, in the range 10–25%RH at room temperature, and the average sensitivity for the entire range of %RH was 7.33 MΩ/%RH and 9.42 MΩ/%RH, respectively, for the two glasses. The aging effect for samples was found to be negligible; hence they are stable against time, which makes them suitable for use as humidity sensors. The repeatability of the sensors was 89% and 94.45%, respectively. [ABSTRACT FROM AUTHOR]

Introduction: There is currently no consensus in the literature concerning the impact of aging on the properties of hyaluronan (HA) in the subcutaneous (SC) space. Recombinant human hyaluronidase PH20 (rHuPH20) facilitates SC administration of injected therapeutics by depolymerizing SC HA, facilitating bulk fluid flow, dispersion and absorption. This study assessed the impact of intrinsic aging on HA in the SC space and thus the ability of rHuPH20 to enhance delivery of co-administered therapeutics. Methods: Histologic evaluations of HA levels and degradation were performed on human skin samples from six age groups, aged from 20 to 100 years. HA levels were evaluated by HA staining and degradation by staining samples for HA following incubation with rHuPH20. HA was extracted from samples and HA size determined by gel electrophoresis. Dermal reconstitution was assessed in young (aged 1.5 months) and elderly (aged > 16 months) mice. Baseline dye dispersion was measured at 5 and 20 min post-intradermal dye injection. Following treatment with rHuPH20, dye dispersion was measured again at 2, 24, 48, 72 and 96 h. Results: Distribution of HA was confined to the interstitial space between adipocytes, with similar pericellular presence and levels of HA found across all age groups. Substantial levels of high-molecular-weight HA were observed in all age groups at baseline. Incubation with a clinically relevant dose of rHuPH20 resulted in degradation of all SC HA and similar degradation profiles independent of age. No difference in dye dispersion time was observed between young and elderly mice across the range of time points assessed, with dye dispersion returning to baseline levels by 24 h after rHuPH20 treatment. Conclusions: Subcutaneous delivery of approved therapeutics facilitated by co-administration with rHuPH20 should not be impacted by intrinsic aging, with this study providing no evidence for an effect of aging on HA distribution, structure or a loss of rHuPH20 efficacy. [ABSTRACT FROM AUTHOR]

This paper takes into account a single facility that produces good quality as well as defective units in batches. In addition, units produced on the facility are inspected for quality in batches. Herein, after the inspection is completed, the defective units of the inspected batch are reworked. Each reworked unit has the required good quality. When the facility is related to reworking defective units, there is an aging effect in which the processing time of a defective unit depends on its position in a sequence. Subsequently, when reworking of all defective units in each batch is completed, a maintenance activity is required, after which the facility will be restored to its initial condition. In addition, it is assumed that the percentage of the defective units is the same in each batch. The objective is to find the number of batches and their (integer) size such that the makespan is minimized. The major contributions of this paper can be summarized in two aspects. Firstly, we propose a new reasonable model for an imperfect production of a single product, and secondly, to solve the proposed model, a hybrid meta-heuristic algorithm comprising genetic algorithm, variable neighborhood search and simulated annealing algorithms is developed. The experimental results confirms that the hybrid algorithm can be proposed to sustainably solve this problem. [ABSTRACT FROM AUTHOR]

Abstract: High-TC GdBa2Cu3O7−δ (GdBCO) superconductor has been popular for making superconductive tapes that have much potential for various fields of large-scale applications. We investigated aging effects on the microwave surface resistance (RS) of Ag-coated GdBCO layer on Hastelloy substrate, so called GdBCO coated conductors (CCs), and Ag-coated GdBCO films on LaAlO3 (LAO) single-crystal substrates at cryogenic temperatures and compared them with each other. Unlike the RS of Ag-coated GdBCO films showing significant degradation in 4 weeks, no significant aging effects were found in our Ag-coated GdBCO CCs aged 85 weeks. The reactive co-evaporation deposition and reaction (RCE-DR) method was used for preparing the Ag-coated GdBCO CCs. Such durability of the Ag-coated GdBCO CCs in terms of the RS could be explained by existence of a protective impurity phase, i.e., Gd-free Ba-Cu-O phase as confirmed by transmission electron microscopy study combined with the energy-dispersive X-ray spectroscopy measurements. Although the scope of this study is limited to the Ag-coated GdBCO CCs prepared by using the RCE-DR method, our results suggest that a solution for preventing the aging effects on transport properties of other kinds of Ag-coated GdBCO CCs could be realized by means of an artificially-grown protective impurity layer.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The decomposition process of typical energetic material (EM) may consist of thousands of individual reactions as well as many intermediate species. However, one-step decomposition kinetics is routinely utilized for prediction of the shelf life of EMs. The inclusion of detailed multi-step chemistry in the kinetic mechanism can improve the reliability of the lifetime prediction. This study proposes a novel procedure for lifetime prediction of EMs, which adopts isoconversional kinetics to represent the decomposition reaction scheme. The pertinent EMs considered in the study include 97.5% cyclotrimethylene-trnitramine, 95% cyclotetramethylene-tetranitramine (HMX) and boron potassium nitrate. Differential scanning calorimetry was utilized for extracting the said isoconversional kinetics complemented by experimental validation of the proposed chemical kinetics through a comparison of the numerical lifetime predictions with accelerated aging experiment measurements. [ABSTRACT FROM AUTHOR]

The objective of this study was to elucidate the dynamic changes in the properties of biochar-amended soil and their sorption capacity for typical organic contaminants with increasing contact time between biochar and soil. To do so, biochars that were produced from pig manure at two temperatures were added to two soils, and the sorption behaviors of atrazine and phenanthrene (Phen) on soil-biochar mixtures aged for different times were investigated. Soils freshly amended with biochars showed a dramatic increase in the sorption of atrazine (up to 23.4 times at C = 0.01 S ) and Phen (up to 3.12 times at C = 0.01 S ) compared to the bare soils without biochars. The physicochemical properties of soil-biochar mixtures changed with aging time, which in turn affected the sorption capacity. After the biochar produced at 300 °C (BC300) was aged in soil, the sorption of atrazine and Phen by black soil (BS) and fluvo-aquic soil (FS) both increased by different extents, except the sorption of Phen on BS. However, after the biochar produced at 700 °C (BC700) was aged in soil, the sorption of atrazine on the two soils decreased markedly, which was sill 56.3% higher than that on the original soil, while an opposite trend was observed for Phen on the two soils. The complex change patterns could be due to the different dominant sorption mechanisms for different biochars and chemicals. [ABSTRACT FROM AUTHOR]

In this paper, we analyse the parallel machine makespan minimization problem with the general sum of processing time based learning or aging effects. First, we prove that an optimal solution to the single machine case can be found by priority rules. Next, for the considered parallel machine problem, we construct the exact dynamic programming algorithm that can operate on real-valued job processing times, which is the only exact algorithm for the analysed problem. The computational analysis confirms that it can solve optimally moderate problem instances. [ABSTRACT FROM AUTHOR]

We present the method and results of a renormalization group description of nonequilibrium critical relaxation of model A with evolution from an initial high-temperature state. We calculate the two-time dependence of the correlation function and response function and find a violation of the fluctuationdissipation theorem in the nonequilibrium critical regime. For the limit fluctuation-dissipation relation, which is a universal property of the nonequilibrium critical dynamics, we calculate the fluctuation and impurity corrections in the two-loop approximation at the fixed space dimension d = 3 using Padé-Borel summation for asymptotic series. [ABSTRACT FROM AUTHOR]

We present our ongoing research focused on speaker recognition in historical oral archives. This research is part of our long-term effort aimed at enabling versatile access to the archive of the Czech Radio (CRo). Based on a manually annotated partition of the archive, we compiled a database covering a time span of more than 30 years to carry out our experimental study. Hence we were able to investigate the impact of various aspects that make it challenging to process historical data. We show the shift of scores for target (genuine) speaker trials introduced by the aging effect, the value of the signal-to-noise ratio or by the variable amount of the enrollment and test data. Scores for speaker detection trials were assessed by a system based on the i-vector paradigm and probabilistic linear discriminative analysis. We also assessed the performance of this system using an evaluation database containing contemporary recordings collected over a time span of approximately 4 years. Although using state-of-the-art techniques, capable of dealing with nuisance inter-session variability, we demonstrate remarkable degradation in the performance of the system in the evaluation containing historical data compared to the one containing contemporary data only. Specifically, the Equal Error Rate (EER) of the system rose to 8.27 % from 1.93 %. The revealed difference thus exemplifies that compensation techniques need to be employed to cope with additional variability introduced in the historical data by various sources. [ABSTRACT FROM AUTHOR]

The electrical performance of two different types of Cu(In,Ga)Se/CdS solar cells were measured repeatedly over a period of several months. One of the solar cells initially showed cross-over in its current-voltage curve, whereas the other showed normal p- n diode operation. The efficiencies of both devices were found to improve with aging due to the significantly increased doping density in the space charge region. The long-term aging effect was found to be irreversible and disappeared after thermal annealing of the device at relatively low temperature. The increase in doping density was attributed to Cu electromigration under the influence of a built-in electric field existing in the space charge region of the absorbers. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Aging effect can influence the fractions distribution and mobility of metals after they are added into soil. In this study, incubation and soil column experiments under simulated acid rain condition were conducted to evaluate aging effect on the leaching characteristic of Cu, Zn, and Cd in artificial polluted red paddy soil. Our results showed that aging effect reduced metal contents in exchangeable and HoAc soluble fractions. Power function was the most excellent to describe the variation of exchangeable fraction, while pseudo first- and second-order functions were more successful to describe the leaching characteristic of metals from soil columns. The leaching amount of the metals from the polluted soil only accounted for a small part of their total content in soil, and the leachability of Cu was the weakest. Both the exchangeable and HoAc soluble fraction were available as indicators to evaluate the leachability of metals in red paddy soil. The shorter time the soil was contaminated, the more amounts of metals released from the soil. The reduction of exchangeable fraction caused by aging effect was the main reason for the decrease of metal mobility in soil. [ABSTRACT FROM AUTHOR]

This paper considers the single batch-processing machine scheduling problem with aging effect and multi-maintenance activity concept. Real processing time of jobs increases due to machine's aging effect. Maintenance time is constant and the machine returns to its initial condition after each maintenance activity and the aging effect starts anew. Our scheduling problem is under assumptions: non identical job sizes and dynamic job arrivals. We have to determine jointly (1) the maintenance frequencies, (2) the position of the maintenance activities on the machine, (3) the grouping of the jobs into the batches, and (4) the sequence of the batches on the machine, to minimize makespan. At first, we formulate the problem as a mathematical model. Since this problem has been proved to be NP-hard; therefore, a heuristic and two meta-heuristic algorithms are offered for the real-sized problems. The performance of the proposed algorithms is analyzed on the various test problems based on the considered measures. [ABSTRACT FROM AUTHOR]

The objective of this study was to understand the effect of decrease in available radiocesium independently of the potassium and zeolite application effect on the uptake of radiocesium by rice. Brown rice produced in seven paddy fields located at four different sites of Fukushima Prefecture were sampled in 2011 and 2012. Any decontamination treatment was not conducted in these fields during the 2-year period. The Cs-137 concentrations in brown rice was 30 % lower in 2012 (1.3-160 Bq kg) compared to those in 2011 (2.8-290 Bq kg) with neither decontamination nor additional application of potassium and/or zeolite. [ABSTRACT FROM AUTHOR]

In this paper, we consider the multiple common due date assignment and single machine scheduling with a job-dependent aging effect and a deteriorating maintenance activity. Once the maintenance activity has been completed, the machine will revert to its initial condition and the aging effect will start anew, the maintenance duration depends on its starting time. The objective is to minimize the total of earliness, tardiness, due date costs and find the optimal due date, the optimal maintenance position. We introduce an efficient O( n) algorithm to solve the problem. We also provide a special case of the problem and show that it remains polynomial time solvable. [ABSTRACT FROM AUTHOR]

The increasing need to store more and more information has resulted in the fact that Static Random Access Memories (SRAMs) occupy the greatest part of Systems-on-Chip (SoCs). Therefore, SRAM's robustness is considered crucial in order to guarantee the reliability of such SoCs over lifetime. In this context, one of the most important phenomena that degrades Nano-Scale SRAMs reliability is related to Negative-Bias Temperature Instability (NBTI), which causes the memory cells aging. The main goal of this paper is to present a hardware-based approach able to monitor SRAMs' aging during the SoC's lifetime based on the insertion of On-Chip Aging Sensors (OCASs). In more detail, the proposed strategy is based on the connection of one OCAS to every SRAM column, each periodically monitoring write operations on the SRAM cells. It is important to note that in order to prevent the OCAS from aging and to reduce leakage power dissipation, the OCAS circuitry is powered-off during its idle periods. The proposed hardware-based approach has been evaluated throughout SPICE simulations using 65 nm CMOS technology and the results demonstrate the sensor's capacity to detect early aging states and therefore, guaranteeing high SRAM reliability. To conclude, a complete analysis of the sensor's overheads is presented. [ABSTRACT FROM AUTHOR]

We consider a single machine due date assignment scheduling problem with job-dependent aging effects and a deteriorating maintenance activity, where due dates are assigned using the SLK due date determination method. We need to make a decision on when to schedule the deteriorating maintenance activity, the optimal common flow allowance and the sequence of jobs to minimize total earliness, tardiness and common flow allowance cost. We show that the problem remains polynomially solvable under the proposed model. [ABSTRACT FROM AUTHOR]

Four single machine-scheduling problems with general position-dependent aging effect and upper-bounded actual processing times are considered. For the first two problems without machine maintenance consideration, it is shown that they are polynomially solvable. For the last two problems with machine maintenance consideration, two polynomial algorithms are proposed. [ABSTRACT FROM AUTHOR]

According to historical records, the soil in the Xinhua District of Tainan City, Taiwan, has been liquefied several times in 1946, 2010, and 2016. To assess the soil liquefaction resistance and understand the recurring liquefaction mechanism of this site, this study conducts a series of experimental tests, including the undrained dynamic triaxial tests on undisturbed and remolded soil samples retrieved from the site. Different fines contents, dry densities, and effective confining pressures are considered for the remolded samples during the test program to investigate their influence on the soil liquefaction resistance. A complete experimental soil liquefaction resistance curve of the site is constructed based on the test results. The liquefaction resistances of the undisturbed and remolded samples were found to be similar at the recurring liquefaction site in the present study. Besides, the experimental soil liquefaction resistance curve of the recurring liquefaction site was lower than the in situ empirical soil liquefaction resistance curve that is based on all site conditions, including the aging effect. This observation agrees with the other laboratory test and field investigation that the triggered liquefaction leads to the “reset” of the aging effect that lowers the liquefaction resistance. The finding of this study may explain why a recurring liquefaction site is more vulnerable to liquefaction in a seismic event. [ABSTRACT FROM AUTHOR]

This article studies a single-machine scheduling with deteriorating jobs and aging effects under an optional maintenance activity. We assume that after maintenance activity, the machine will revert to its initial condition and the aging effects will start anew. Moreover, due to the restriction of budget of maintenance, the limitation of the maintenance frequency on the machine is assumed to be known in advance. The optional maintenance activity of this study means that the starting time of the maintenance activity is unknown in advance. It can be scheduled immediately after the processing of any job that has been completed. Therefore, the planner must to make decision on whether or when to schedule the maintenance activity during the scheduling horizon to optimal the performance measures. The objective is to minimize the makespan. We first show that the addressed problem is NP-hard in the strong sense. Then a fully polynomial-time approximation scheme (FPTAS) for the proposed problem is presented. [ABSTRACT FROM AUTHOR]

We study the problem of maximizing the weighted number of just-in-time jobs on a single machine with position-dependent processing times. Unlike the vast majority of the literature, we do not restrict ourselves to a specific model of processing time function. Rather, we assume that the processing time function can be of any functional structure that is according to one of the following two cases. The first is the case where the job processing times are under a learning effect, i.e., each job processing time is a non-increasing function of its position in the sequence. In the second case, an aging effect is assumed, i.e., each job processing time is a non-decreasing function of its position in the sequence. We prove that the problem is strongly $$\mathcal{N }\mathcal{P }$$ -hard under a learning effect, even if all the weights are identical. When there is an aging effect, we introduce a dynamic programming (DP) procedure that solves the problem with arbitrary weights in $$O(n^{3})$$ time (where $$n$$ is the number of jobs). For identical weights, a faster optimization algorithm that runs in $$O(n\log n)$$ time is presented. We also extend the analysis to the case of scheduling on a set of $$m$$ parallel unrelated machines and provide a DP procedure that solves the problem in polynomial time, given that $$m$$ is fixed and that the jobs are under an aging effect. [ABSTRACT FROM AUTHOR]

Proofs of strong NP-hardness of single machine and two-machine flowshop scheduling problems with learning or aging effect given in Rudek (Computers & Industrial Engineering 61:20-31, ; Annals of Operations Research 196(1):491-516, ; International Journal of Advanced Manufacturing Technology 59:299-309, ; Applied Mathematics and Computations 218:6498-6510, ; Applied Mathematical Modelling 37:1523-1536, ) contain a common mistake that make them incomplete. We reveal the mistake and provide necessary corrections for the problems in Rudek (Computers & Industrial Engineering 61:20-31, ; Annals of Operations Research 196(1):491-516, ; Applied Mathematical Modelling 37:1523-1536, ). NP-hardness of problems in Rudek (International Journal of Advanced Manufacturing Technology 59:299-309, ; Applied Mathematics and Computations 218:6498-6510, ) remains unknown because of another mistake which we are unable to correct. [ABSTRACT FROM AUTHOR]

We consider single-machine scheduling and slack due-date assignment problems simultaneously with the position-dependent aging effect and deteriorating maintenance. In order to counteract the aging effect on the machine, we assume that at most one maintenance is allowed throughout the planning horizon and the maintenance can be performed immediately after the processing of any job is completed. The maintenance duration is dependent on its starting time. The objective is to find jointly the optimal common slack time, the optimal maintenance position, and the optimal schedule such that the sum of the total earliness, the total tardiness, and the common slack time costs is minimized. We propose polynomial time algorithms for all the problems studied. [ABSTRACT FROM AUTHOR]

In this paper, we focus on real-life settings that require the development of new models of flowshop scheduling problems, where job processing times can increase with the number of processed jobs due to the aging effect and decrease by the allocation of additional resource. We analyse the makespan minimization flowshop problem with such model and also with the aging effect only. We prove that the considered problems and their special cases are still polynomially solvable under given conditions, and on their basis, we provide optimal polynomial time solution algorithms. [ABSTRACT FROM AUTHOR]

In this paper, we analyse single machine scheduling problems with learning and aging effects to minimize one of the following objectives: the makespan with release dates, the maximum lateness and the number of late jobs. The phenomena of learning and aging are modeled by job processing times described by non-increasing (learning) or non-decreasing (aging) functions dependent on the number of previously processed jobs, i.e., a job position in a sequence. We prove that the considered problems are strongly NP-hard even if job processing times are described by simple linear functions dependent on a number of processed jobs. Additionally, we show a property of equivalence between problems with learning and aging models. We also prove that if the function describing decrease/increase of a job processing time is the same for each job then the problems with the considered objectives are polynomially solvable even if the function is arbitrary. Therefore, we determine the boundary between polynomially solvable and strongly NP-hard cases. [ABSTRACT FROM AUTHOR]

Purpose: We used a sequential extraction to investigate the effects of compost amendment on Cd fractionation in soil during different incubation periods in order to assess Cd stabilization in soil over time. Methods: Pot experiments using rice plants growing on Cd-spiked soils were carried out to evaluate the influence of compost amendment on plant growth and Cd accumulation by rice. Two agricultural soils (Pinchen and Lukang) of Taiwan were used for the experiments. The relationship between the redistribution of Cd fractions and the reduction of plant Cd concentration due to compost amendment was then investigated. Results and discussion: Compost amendment in Pinchen soil (lower pH) could transform exchangeable Cd into the Fe- and Mn-oxide-bound forms. With increasing incubation time, exchangeable Cd tended to transform into carbonate- and Fe- and Mn-oxide-bound fractions. In Lukang soil (higher pH), carbonate- and Fe- and Mn-oxide-bonded Cd were the main fractions. Exchangeable Cd was low. Compost amendment transformed the carbonate-bound form into the Fe and Mn oxide form. Pot experiments of rice plants showed that compost amendment enhanced plant growth more in Pinchen soil than in Lukang soil. Compost amendment could significantly reduce Cd accumulation in rice roots in both Pinchen and Lukang soils and restrict internal transport of Cd from the roots to the shoots. Because exchangeable Cd can be transformed into the stronger bonded fractions quickly in Pinchen soil, a reduction of Cd accumulation in rice due to compost amendment of Pinchen soil was significant by 45 days of growth. However, carbonate-bonded fractions in Lukang soil may provide a source of available Cd to rice plants, and exchangeable and carbonate-bonded fractions are transformed into the other fractions slowly. Thus, reduction of Cd accumulation by rice due to compost amendment in Lukang soil was significant by 75 days of growth. Conclusions: The results of the study suggest that the effectiveness of compost amendment used for stabilization of Cd and to decrease the phytoavailability of Cd for rice plants is different in acidic and alkaline soils. In acidic soil, Cd fractionation redistributes quickly after compost amendment and shows a significant reduction of Cd accumulation by the plant within a few weeks. In alkaline soil, due to the strongly bound fractions of Cd being in greater quantity than the weakly bound ones, a longer period (a few months) to redistribute Cd fractions is needed. [ABSTRACT FROM AUTHOR]

The thermal responses of the saturated silty clay to repeated heating-cooling are studied in laboratory. Results show that the pore pressure induced by undrained heating increases with increasing temperature, but the peak pore pressure appears a degradation trend with increasing temperature cycles. During the consolidation process at an elevated temperature, the specimen contracts due to the dissipation of the pore pressure; however, the thermally induced pore pressure is under no conditions fully dissipated to zero, therefore, there always exists a residual pore pressure in the specimens once a thermal loading higher than the ambient temperature is applied. During the undrained cooling, pore pressure continues to decline and eventually falls below zero. During the isothermal consolidation at the original temperature, the specimen begins to expand due to water absorption caused by the negative pore pressure, and eventually reaches a steady value. In addition, the consolidation volumetric strain generated during the drainage process at 50°C is greater than that during the water absorption process at 25°C, the difference seems to be most obvious for the first three cycles, and begins to diminish gradually thereafter. [ABSTRACT FROM AUTHOR]

In this paper, we analyze some single machine scheduling problems with the aging effect. We extend the sum-of-processing-time-based aging model such that the fatigue caused by each job to the machine is equal to a non-increasing function dependent on the normal processing time of a job and the aging effect is job dependent. Although the proposed model is more general and describes more precisely the real-life settings, we show that the special cases of the maximum completion time and the maximum lateness minimization problems with this model are still polynomially solvable. However, we prove the maximum completion time minimization problem with the sum-of-processing-time-based aging model is strongly NP-hard if some jobs have deadlines and constant processing times. On this basis, we show that the maximum lateness minimization problem with this aging model is also strongly NP-hard. [ABSTRACT FROM AUTHOR]

Spin dynamics in mechanochemically obtained nanoparticle manganite LaCaMnO was investigated in this study by means of a series of AC and DC magnetic measurements. AC susceptibility indicates the presence of sizeable interparticle interactions, yielding collective magnetic behavior. The related properties were probed by experiments in weak DC field: memory effects were analyzed in both field-cooled (FC) and zero field-cooled (ZFC) regimes, while, after ZFC aging, magnetic relaxation was recorded. The system appears to be sensitive to magnetothermal history, in analogy with spin-glass-like compounds. The analysis of the data indicates the occurrence of slow dynamics in an ensemble of strongly interacting super spins. [ABSTRACT FROM AUTHOR]

In this work, we study the long-term aging effect caused by Fe atoms in the superconductor CaLaBa{CuFe}O with 0 ≤ x ≤ 0.07. XRD confirms that this system has a YBCO-like structure. The critical temperature (T) is strongly affected by aging and depends on the amount of Fe in the structure. Room temperature Mössbauer spectroscopy reveals the presence of the typical species A, B- B ′, C and new species E ′ and F. Interestingly; A, which corresponds to the Fe atom located in the Cu(1) of the chains with spin S = 3/2, shows a drastic reduction which means migration to the species B, B ′ and C. Species B and B ′ correspond to the Fe in the Cu(2) site forming planar quasi-octahedral and planar square pyramidal, while the C specie is a square pyramidal with O(5) respectively (spin S = 3/2 in all these cases). Aging causes loss of superconductivity in the samples with 5 and 7% of iron content. [ABSTRACT FROM AUTHOR]

The bioavailability of copper in contaminated soils has received more attention due to the safety concern of food chain. The bioavailability of metals is determined by its fractions which are affected by the soil properties and its aging time. This paper focused on the aging effect on the bioavailability of copper added to the soil. The garden soil (fluvo aquic soil) was treated with 100 mg/kg and 1000 mg/kg of copper(II) sulfate and incubated for 14, 21, 28, 42, 63, 120, 200, 300 and 400 days in the laboratory respectively. The sequential extraction procedure was used to characterize copper bioavailability in the soil. Meanwhile, the barley was cultured on the same soil incubated and its toxicity was assessed according to the guideline of International Organization for Standardization. The findings show that the exchangeable and carbonate-bound copper decreased with the aging time after addition of copper(II) sulfate to soil. Meanwhile, the percentages of Fe-Mn oxides- and organic-bound copper increased. The residual copper was changed little during the aging course. The copper fractions became stable in soils after 60 days. The kinetic equations showed that the Power function and the Elovich equation were well fitted to the experimental data, and the r² values ranged from 0.840 to 0.982 and 0.741 to 0.975, respectively. The barley test showed that the barley root length was more sensitive to reflect copper toxicity than the shoot biomass, and the exchangeable and carbonate-bound copper were significantly correlated with the barley root length. [ABSTRACT FROM AUTHOR]

n energy based fatigue life prediction framework has been developed for calculation of remaining fatigue life of in service gas turbine materials. The purpose of the life prediction framework is to account aging effect caused by cyclic loadings on fatigue strength of gas turbine engines structural components which are usually designed for very long life. Previous studies indicate the total strain energy dissipated during a monotonic fracture process and a cyclic process is a material property that can be determined by measuring the area underneath the monotonic true stress-strain curve and the sum of the area within each hysteresis loop in the cyclic process, respectively. The energy-based fatigue life prediction framework consists of the following entities: (1) development of a testing procedure to achieve plastic energy dissipation per life cycle and (2) incorporation of an energy-based fatigue life calculation scheme to determine the remaining fatigue life of in-service gas turbine materials. The accuracy of the remaining fatigue life prediction method was verified by comparison between model approximation and experimental results of Aluminum 6061-T6. The comparison shows promising agreement, thus validating the capability of the framework to produce accurate fatigue life prediction. [ABSTRACT FROM AUTHOR]

A new scheduling model in which both two-agent and position-dependent processing times exist simultaneously is considered in this paper. Two agents compete to perform their respective jobs on a common single machine, and each agent has his own criterion to optimize. The job position-dependent processing time is characterized by increasing or decreasing function dependent on the position of a job in the sequence. We introduce an aging effect and a learning effect into the two-agent single-machine scheduling, where the objective is to minimize the total completion time of the first agent with the restriction that the maximum cost of the second agent cannot exceed a given upper bound. We propose the optimal properties for the considered scheduling problems and then present the optimal polynomial time algorithms to solve the two scheduling problems, respectively. [ABSTRACT FROM AUTHOR]

Time-dependent changes of phytoavailability of Sr after adding it to the soil were studied for better prediction of radioactive Sr behavior in soil–plant systems. Strontium-86 enriched stable isotope was added to a soil sample collected from a field of humus-rich Andosol. Plant uptake and extractability of Sr in the soil were assessed at given times after the addition during a 12-month period including repeated drying-rewetting. Proportion of the added Sr extracted by 1 M ammonium acetate solution from the soil was 45–58% throughout the period, which corresponded to that of long-time aged 90Sr in the soil. Pot cultivations of orchardgrass ( Dactylis glomerata) and red clover ( Trifolium pratense) were carried out starting with uncropped soil for four weeks five times during the experiment. Clear time-dependent changes were not observed in uptake of the added Sr by the plants. Aging is unlikely to decrease Sr availability over time. The labile form of Sr determined with the isotopic dilution method was approximately 15% of total soil Sr, and more than the percentage of the extractable Sr in the soil. The results suggest that a part of the non-extractable forms of Sr in the soil would be available to the plant. [ABSTRACT FROM AUTHOR]

This report investigates the phenomenon of interfacial serration at the joint between Sn-3.5Ag-0.7Cu solder (SAC) and electroless Ni-P underbump metallization (UBM) during aging. For comparison, the interface between SAC and electrolytic Ni UBM was also examined under similar aging conditions. The joint in the electrolytic Ni/SAC sample showed a smooth, flat interface between the Ni and intermetallic compounds, even after a long aging time. In contrast, electroless Ni-P/SAC exhibited an irregular interface, the irregularity of which became more severe with increased aging time. This observed roughness was initiated by large breaks across the P-rich layer. The breaks were filled with the overlying Ni-Sn-P phase material, which provided an easier interdiffusion path for Ni and Sn in the opposite direction. As a result, the local consumption of the Ni(-P) layer was accelerated, and the interface was serrated. The local maximum consumption rate of the Ni-P layer, as calculated from the minimum thickness of this layer in each sample with aging time, was similar to that of an electrolytic Ni layer. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare and characterize beads of Gelucire 43/01 for floating delivery of metformin hydrochloride (MH). The beads were evaluated for particle size, surface morphology, percent drug entrapment, percent yield, differential scanning calorimetry (DSC), in vitro floating ability, and in vitro drug release. Aging effect on storage was evaluated using hot stage microscopy (HSM), DSC, scanning electron microscopy, and in vitro floating ability. The formed beads were sufficiently hard and spherical in shape. Photomicrographs show that the surface was porous in nature. The average particle diameter of beads was found to be in the size range of 3.85 to 3.95 mm, and percent entrapment was 83.07% to 86.13%. The beads demonstrated favorable in vitro floating ability. The analysis of DSC thermograms revealed no physical interaction between the lipid and the drug in the prepared beads. Prepared formulations showed better controlled release behavior when compared with its conventional dosage form and comparable release profile with marketed sustained release product. HSM photomicrograph showed presence of some unmelted portion even at 43°C and completely melts on 51°C in aged sample. It was found that there was no significant effect on floating ability of aged beads since it remains floats up to 8 h study period. Thus, it is concluded that beads of Gelucire 43/01 could be serve as an effective carrier for highly water-soluble antihyperglycemic drugs like MH for the controlled delivery. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA) membranes crosslinked with poly(acrylic acid- co-maleic acid) (PAM) were prepared to investigate the effect of aging on their morphology by swelling them for up to 7 days. PAM was used both as a crosslinking agent and as a donor of the hydrophilic -COOH group. A 30 wt% weight loss of the dry membrane was observed in the swelling test after 6 days. The surface of the membrane was dramatically changed after the swelling test. The surface roughness of the PVA/PAM membrane was increased, as determined by atomic force microscopy (AFM). The swelling loosened the polymer structure, due to the release of the unreacted polymer and the decomposition of the ester bond, thereby resulting in an increase in the free volume capable of containing water molecules. The water molecules present in the form of free water were determined by differential scanning calorimetry (DSC). The fraction of free water increased with increasing swelling time. The swelling of the membrane may provide space for the transport of protons and increase the mobility of the protonic charge carriers. The proton conductivity of the membranes measured at T=30 and 50 °C was in the range of 10 to 10 S/cm, and slightly increased with increasing swelling time and temperature. [ABSTRACT FROM AUTHOR]

Stainless steel plates (AISI 304L) were treated by an atmospheric pressure plasma treatment at room temperature in order to modify the surface properties. After plasma treatment, the surface wettability and the surface free energy were both improved. The wettability and the surface free energy of stainless steel plates before and after plasma treatment were measured from the results of contact angle test. Through the results of contact angle and surface free energy, optimum plasma treatment conditions were obtained, such as the treatment time of 60 sec and the treatment power of 120 W. In addition to this, the optimum aging time was 3 to 5 min in air. [ABSTRACT FROM AUTHOR]

Isotactic polypropylene (PP) surfaces were modified with argon and oxygen plasmas using a radiofrequency (RF) glow discharge at 240 mTorr and 40 W. The changes in topography and surface structure were investigated by atomic force microscopy (AFM) in conjunction with specular reflectance of infrared (IR) microspectroscopy. Under our operating conditions, the AFM image analysis revealed that longer plasma treatment resulted in significant ablation on the PP surface, regardless of the kind of plasma employed, but the topography was dependent on the nature of the gases. Specular reflectance IR spectroscopic analysis indicated that the constant removal of surface material was an important ablative aspect when using either plasma, but the nature of the ablative behavior and the resultant aging effects were clearly dependent on the choice of plasma. The use of argon plasma resulted in a negligible aging effect; in contrast, the use of oxygen plasma caused a noticeable aging effect, which was due to reactions of trapped or isolated radicals with oxygen in air, and was partly responsible for the increased surface area caused by ablation. The use of oxygen plasma is believed to be an advantageous approach to modifying polymeric materials with functionalized surfaces, e.g., for surface grafting of unsaturated monomers and incorporating oxygen-containing groups onto PP. [ABSTRACT FROM AUTHOR]

Aging and compositional effects of silicalite layer synthesis on a quartz surface using the vapor phase transport method were studied. Silicalite layers can be synthesized from a wide compositional range when not-aged mixtures were used. But reproducibility of the film synthesis was low due to the heterogeneity of the starting mixtures. In order to increase the reproducibility, both aging of the starting mixtures and compositional changes were attempted. Silicalite layer can be synthesized successfully on quartz surface within 0.3 of the ratio TPAOH/SiO2. Higher ratio of TPAOH/SiO2 smaller crystals are formed. If the TPAOH/SiO2 ratio is larger than 0.3, the formed silicalite crystal cannot be attached on the quartz surface. When the TPAOH/SiO2 ratio of the aged starting mixture was 0.28, requirements for both reproducibility and smaller crystal size resulted were satisfied. The crystal size and shape in the silicalite layer are also influenced by the water content in the mixture. The crystal size in the silicalite layer increases with increasing water content in the mixture. [ABSTRACT FROM AUTHOR]

The hobo transposon is responsible for one of the three hybrid dysgenic systems that have been described in Drosophila melanogaster. Most studies on the hobo dysgenic system have been carried out using the PM system as a reference. However, these two systems differ significantly. In particular, several studies have failed to find any correlation between the molecular structures of hobo elements, the instability of the transposon and the incidence of gonadal dysgenic (GD) sterility. On the other hand, no study of the ability of females to permit hobo activity in their progeny when they are crossed with males harboring active hobo elements (permissivity) has yet been reported. In order to investigate the parameters involved in hobo permissivity, four E strains were studied with regard to the molecular nature of their hobo sequences and the GD sterility induced by a controlled source of hobo transposase. We show that hobo permissivity varies both within and between E strains. Moreover, permissivity decreases with age in E females. Our results are discussed with respect to similar phenomena that have been described in relation to the reactivity of the IR dysgenic system. [ABSTRACT FROM AUTHOR]