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991.
In this paper, a reliable stochastic numerical analysis for typhoid fever incorporating with protection against infection has been considered. We have compared the solutions of stochastic and deterministic typhoid fever model. It has been shown that the stochastic typhoid fever model is more realistic as compared to the deterministic typhoid fever model. The effect of threshold number T* hold in stochastic typhoid fever model. The proposed framework of the stochastic non-standard finite difference scheme (SNSFD) preserves all dynamical properties like positivity, bounded-ness and dynamical consistency defined by Mickens, R. E. The stochastic numerical simulation of the model showed that increase in protection leads to low disease prevalence in a population.  相似文献   
992.
993.
A control chart based on double exponentially weighted moving average and Benjamini‐Hochberg multiple testing procedure is proposed that controls the false discovery rate (FDR). The proposed control chart is based on probabilities (or P values) to accept or reject the null hypothesis of the underlying process is in control. To make a decision, instead of using only the current probability, previous “m” probabilities are considered. The performance of the control chart is evaluated in terms of average run length (ARL) using Monte Carlo simulations. Procedure for estimation of parameters used in the control chart is also discussed. The proposed control chart is compared with previous control charts and found to be more efficient in controlling the false discovery rate.  相似文献   
994.
995.
996.
The large‐scale application of sodium/potassium‐ion batteries is severely limited by the low and slow charge storage dynamics of electrode materials. The crystalline carbons exhibit poor insertion capability of large Na+/K+ ions, which limits the storage capability of Na/K batteries. Herein, porous S and N co‐doped thin carbon (S/N@C) with shell‐like (shell size ≈20–30 nm, shell wall ≈8–10 nm) morphology for enhanced Na+/K+ storage is presented. Thanks to the hollow structure and thin shell‐wall, S/N@C exhibits an excellent Na+/K+ storage capability with fast mass transport at higher current densities, leading to limited compromise over charge storage at high charge/discharge rates. The S/N@C delivers a high reversible capacity of 448 mAh g‐1 for Na battery, at the current density of 100 mA g‐1 and maintains a discharge capacity up to 337 mAh g‐1 at 1000 mA g‐1. Owing to shortened diffusion pathways, S/N@C delivers an unprecedented discharge capacity of 204 and 169 mAh g‐1 at extremely high current densities of 16 000 and 32 000 mA g‐1, respectively, with excellent reversible capacity for 4500 cycles. Moreover, S/N@C exhibits high K+ storage capability (320 mAh g‐1 at current density of 50 mA g‐1) and excellent cyclic life.  相似文献   
997.
Smart materials are versatile material systems which exhibit a measurable response to external stimuli. Recently, smart material systems have been developed which incorporate graphene in order to share on its various advantageous properties, such as mechanical strength, electrical conductivity, and thermal conductivity as well as to achieve unique stimuli-dependent responses. Here, a graphene fiber-based smart material that exhibits reversible electrical conductivity switching at a relatively low temperature (60 °C), is reported. Using molecular dynamics (MD) simulation and density functional theory-based non-equilibrium Green's function (DFT-NEGF) approach, it is revealed that this thermo-response behavior is due to the change in configuration of amphiphilic triblock dispersant molecules occurring in the graphene fiber during heating or cooling. These conformational changes alter the total number of graphene-graphene contacts within the composite material system, and thus the electrical conductivity as well. Additionally, this graphene fiber fabrication approach uses a scalable, facile, water-based method, that makes it easy to modify material composition ratios. In all, this work represents an important step forward to enable complete functional tuning of graphene-based smart materials at the nanoscale while increasing commercialization viability.  相似文献   
998.
Metal–organic frameworks (MOFs) have been intensively studied over the past decade because they represent a new category of hybrid inorganic–organic materials with extensive surface areas, ultrahigh porosity, along with the extraordinary tailorability of structure, shape and dimensions. In this highlight, we summarize the current state of MOF research and report on structure–property relationships for nonlinear optical (NLO) and dielectric applications. We focus on the design principles and structural elements needed to develop potential NLO and low dielectric (low-κ) MOFs with an emphasis on enhancing material performance. In addition, we highlight experimental evidence for the design of devices for low-dielectric applications. These results motivate us to develop better low-dielectric and NLO materials and to perform in-depth studies related to deposition techniques, patterning and the mechanical performance of these materials in the future.  相似文献   
999.
As a result of repeated rehabilitation efforts over the past few decades, often asphalt pavements have become deep-strength pavements. Consequently, top-down cracking has become a primary distress type. In particular, the top-down cracking performance of warm mix asphalt (WMA) pavements, i.e. how does it compare with similar hot mix asphalt (HMA) pavements is largely unclear mainly due to the lack of field performance data. This paper presents an effort of monitoring the top-down cracking performance of 28 pavement projects including WMA pavements and their corresponding HMA control pavements with service lives ranging between 4 and 10 years. These pavements cover different climate zones, WMA technologies, service years, pavement structures and traffic volume levels. Two rounds of distress surveys were conducted at a two-year interval, and the material (asphalt binder and mixture) properties of the pavements were determined using field cores. The top-down cracking performance of the HMA and WMA pavements was compared based on the first and second round distress surveys. It was found that the HMA and WMA pavement in general exhibited comparable performance. The significant determinants (material properties) for top-down cracking were determined, which were vertical failure deformation of mixes measured at 20 °C from indirect tension test.  相似文献   
1000.
This research was aimed at processing of metallic fiber hybrid spun yarns consisting of polyester/stainless steel and viscose/stainless steel staple fibers to achieve better electrical conductivity. Conventional ring spinning machine and ring twister machine were used to produce the single and plied yarns respectively. The linear electrical resistance of yarns was analyzed with reference to the three levels of twist multiplier (TM) for same yarn count, three levels of yarn fineness (Ne) at the same TM level, and number of plies for the same final yarn count. These results showed that by increasing twist, the electrical conductivity of yarn was increased. However, yarn fineness was in inverse relation with the electrical conductivity of yarns. The effect of yarn plying and twisting to produce the Ne 10s yarn was also found critical in governing the electrical properties. The electrical conductivity of viscose and stainless steel hybrid yarn was found more sensitive to increase with an increase in relative humidity contrary to that of polyester and stainless steel hybrid yarns. The findings of the study are significant to produce the hybrid spun conductive yarns for their potential applications in a variety of tailor-made functional, protective and smart textiles.  相似文献   
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