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排序方式: 共有1118条查询结果,搜索用时 15 毫秒
141.
Wireless Personal Communications - In this paper, we have proposed a lightweight blockchain based model to provide distributed authentication and anonymous authorization in IoD. We have proposed... 相似文献
142.
In this communication, we report on the bulk and lattice thermal expansion studies on a number of compounds, within the homogeneity range of solid solutions, in a series with the general composition Ce1−xSrxO2−x (0.0≤x≤0.10). The XRD pattern of each product was refined to determine the solid solubility of SrO into the lattice of CeO2, and the homogeneity range. The composition with maximum solid solubility limit of SrO in CeO2 lattice, under the slow cooled conditions, was delineated as Ce0.91Sr0.09O1.91 (i.e. 9 mol.% of SrO). The bulk thermal expansion measurements from ambient to 1123 K, as investigated by a dilatometer, revealed that the l (293 to 1123 K) values for the compositions within the homogeneity range increase from 11.58×10−6 to 12.13×10−6 K−1 on increasing the Sr2+ content from 0 mol.% (i.e. CeO2) to 9 mol.%, i.e. the upper solubility limit of SrO into the lattice of CeO2. A similar trend was observed in the lattice thermal expansion coefficients a (293 to 1473 K) as obtained by a high temperature-XRD. 相似文献
143.
In this paper, the solitary wave solutions of (3+1)-dimensional extended Zakharov–Kuznetsov (eZK) equation are constructed which appear in the magnetized two-ion-temperature dusty plasma and quantum physics. Lie group of transformation method is proposed to investigate the solution of (3+1)-dimensional eZK equation via Lie symmetry method. The optimal system of one dimensional Lie subalgebra is constructed by using Lie point symmetries. The three dimensional eZK equation reduced into number of ordinary differential equations (ODEs) by applying similarity reductions. Consequently, solutions so extracted are more general than erstwhile known results. We have obtained twenty one solutions in the explicit form, some of them are likewise general and some are new for the best study of us. Eventually, single soliton, quasi-periodic soliton, multisoliton, lump-type soliton, traveling wave and solitary wave-interaction behavior are illustrated graphically through numerical simulation for physical affirmation of the results. Please check whether the affiliations are correct. 相似文献
144.
Rakeshkumar Vanzara Priyanka Sharma Haresh S. Bhatt Sudeep Tanwar Sudhanshu Tyagi Neeraj Kumar Mohammad S. Obaidat 《International Journal of Communication Systems》2019,32(2)
Due to the widespread popularity and usage of Internet of things (IoT)‐enabled devices, there is an exponential increase in the data traffic generated from these IoT devices. Most of these devices communicate with each other using heterogeneous links having constraints such as latency, throughput, and interference from concurrent transmissions. This results in an extra burden on the underlying communication infrastructure to manage the traffic within these constraints between source and destination. However, most of the existing applications use different Transmission Control Protocol (TCP) variants for traffic management between these devices and are dependent on the stage of the sender, irrespective of the application types and link characteristics. Each operating system (OS) has different TCP variant for all applications, irrespective of path characteristics. Hence, a single TCP variant cannot select the best suitable link, which results in degradation in throughput compared to the existing default. Moreover, it cannot use the full capacity of the available link for different applications and network links, especially in heterogeneous network such as IoT. To cope up with these challenges, in this paper, we propose an Adaptive and Dynamic TCP Interface Architecture (ADYTIA). ADYTIA allows the usage of different TCP variants based on application and link characteristics, irrespective of the physical links of the entire path. It allows the usage of different TCP variants based on their design principle across heterogeneous technologies, platforms, and applications. ADYTIA is implemented on NS‐2 and Linux kernel for real testbed experiments. Its ability to select the best suitable TCP variant results in 20% to 80% improvement in throughput compared with the existing default and single TCP variant on Linux and Windows. 相似文献
145.
Neural Processing Letters - We propose a multi-step training method for designing generalized linear classifiers. First, an initial multi-class linear classifier is found through regression. Then... 相似文献
146.
Houk Jang Krishna P. Dhakal Kyung‐Il Joo Won Seok Yun Sachin M. Shinde Xiang Chen Soon Moon Jeong Suk Woo Lee Zonghoon Lee JaeDong Lee Jong‐Hyun Ahn Hyunmin Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(14)
Understanding the collaborative behaviors of the excitons and phonons that result from light–matter interactions is important for interpreting and optimizing the underlying fundamental physics at work in devices made from atomically thin materials. In this study, the generation of exciton‐coupled phonon vibration from molybdenum disulfide (MoS2) nanosheets in a pre‐excitonic resonance condition is reported. A strong rise‐to‐decay profile for the transient second‐harmonic generation (TSHG) of the probe pulse is achieved by applying substantial (20%) beam polarization normal to the nanosheet plane, and tuning the wavelength of the pump beam to the absorption of the A‐exciton. The time‐dependent TSHG signals clearly exhibit acoustic phonon generation at vibration modes below 10 cm?1 (close to the Γ point) after the photoinduced energy is transferred from exciton to phonon in a nonradiative fashion. Interestingly, by observing the TSHG signal oscillation period from MoS2 samples of varying thicknesses, the speed of the supersonic waves generated in the out‐of‐plane direction (Mach 8.6) is generated. Additionally, TSHG microscopy reveals critical information about the phase and amplitude of the acoustic phonons from different edge chiralities (armchair and zigzag) of the MoS2 monolayers. This suggests that the technique could be used more broadly to study ultrafast physics and chemistry in low‐dimensional materials and their hybrids with ultrahigh fidelity. 相似文献
147.
Carrier Dynamics: Transient SHG Imaging on Ultrafast Carrier Dynamics of MoS2 Nanosheets (Adv. Mater. 14/2018) 下载免费PDF全文
148.
149.
Polycaprolactone (PCL) was reinforced with natural fibres as they not only permit a substantial reduction of the material costs, but also play a role as reinforcement in mechanical properties. This work was focused on the estimation of mechanical and thermal behaviour based on PCL and Pine Cone particles (PCP) filler at different weight percentages (0, 5, 10, 15, 30 and 45 wt%). Tests results indicated considerable improvement in mechanical properties, corresponding to a gain in impact strength and % elongation of 6 and 9.2% at 15 wt% particle loading, respectively. Some decrease in thermal stability was observed for composites with increasing filler content where as composite at 15% PCP was not significantly affected. Lower melting and crystallization enthalpies and higher crystallinity values were obtained for bio-composites compared with neat PCL. Some decrease in thermal stability and increase in oxygen and water vapour barrier properties were also observed for composites with increasing filler content. 相似文献
150.
Sarvi Yadav Rajesh Sachin Kumar Singh Parth Sharma Palak Bawa Bimlesh Kumar 《Drug development and industrial pharmacy》2018,44(7):1056-1069
Development of self-nanoemulsifying drug delivery systems (SNEDDS) of glimepiride is reported with the aim to achieve its oral delivery. Lauroglycol FCC, Tween-80, and ethanol were used as oil, surfactant, and co-surfactant, respectively as independent variables. The optimized composition of SNEDDS formulation (F1) was 10% v/v Lauroglycol FCC, 45% v/v Tween 80, 45% v/v ethanol, and 0.005% w/v glimepiride. Further, the optimized liquid SNEDDS were solidified through spray drying using various hydrophilic and hydrophobic carriers. Among the various carriers, Aerosil 200 was found to provide desirable flow, compression, dissolution, and diffusion. Both, liquid and solid-SNEDDS have shown release of more than 90% within 10?min. Results of permeation studies performed on Caco-2 cell showed that optimized SNEDDS exhibited 1.54 times higher drug permeation amount and 0.57 times lower drug excretion amount than that of market tablets at 4?hours (p?.01). Further, the cytotoxicity study performed on Caco-2 cell revealed that the cell viability was lower in SNEDDS (92.22%?±?4.18%) compared with the market tablets (95.54%?±?3.22%; p?>?.05, i.e. 0.74). The formulation was found stable with temperature variation and freeze thaw cycles in terms of droplet size, zeta potential, drug precipitation and phase separation. Crystalline glimepiride was observed in amorphous state in solid SNEDDS when characterized through DSC, PXRD, and FT-IR studies. The study revealed successful formulation of SNEDDS for glimepiride. 相似文献