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排序方式: 共有532条查询结果,搜索用时 15 毫秒
1.
Hanafizadeh Payam Hatami Lankarani Ferdos Nikou Shahrokh 《Information Systems and E-Business Management》2022,20(4):749-787
Information Systems and e-Business Management - The growing use of the internet of things (IoT) has provided businesses with a new opportunity. This study performed a systematic literature review... 相似文献
2.
Amini Amir Jafari Azin Vafaei Mostafa Mahmoodian Mehrnoosh 《Journal of Materials Science: Materials in Electronics》2022,33(3):1293-1306
Journal of Materials Science: Materials in Electronics - The main weakness of polymer gas sensors is its stability. Here, we report stability enhancement of a 100 nm polypyrrole (PPy) thin... 相似文献
3.
Liangtao Yang Liang-Yin Kuo Juan Miguel López del Amo Prasant Kumar Nayak Katherine A. Mazzio Sebastian Maletti Daria Mikhailova Lars Giebeler Payam Kaghazchi Teófilo Rojo Philipp Adelhelm 《Advanced functional materials》2021,31(38):2102939
A known strategy for improving the properties of layered oxide electrodes in sodium-ion batteries is the partial substitution of transition metals by Li. Herein, the role of Li as a defect and its impact on sodium storage in P2-Na0.67Mn0.6Ni0.2Li0.2O2 is discussed. In tandem with electrochemical studies, the electronic and atomic structure are studied using solid-state NMR, operando XRD, and density functional theory (DFT). For the as-synthesized material, Li is located in comparable amounts within the sodium and the transition metal oxide (TMO) layers. Desodiation leads to a redistribution of Li ions within the crystal lattice. During charging, Li ions from the Na layer first migrate to the TMO layer before reversing their course at low Na contents. There is little change in the lattice parameters during charging/discharging, indicating stabilization of the P2 structure. This leads to a solid-solution type storage mechanism (sloping voltage profile) and hence excellent cycle life with a capacity of 110 mAh g-1 after 100 cycles. In contrast, the Li-free compositions Na0.67Mn0.6Ni0.4O2 and Na0.67Mn0.8Ni0.2O2 show phase transitions and a stair-case voltage profile. The capacity is found to originate from mainly Ni3+/Ni4+ and O2-/O2-δ redox processes by DFT, although a small contribution from Mn4+/Mn5+ to the capacity cannot be excluded. 相似文献
4.
Porkar Rezaeiye Payam Sharifi Arash Rahmani Amir Masoud Dehghan Mehdi 《The Journal of supercomputing》2021,77(12):14207-14229
The Journal of Supercomputing - With the expansion in the use of IoT, increasing the efficiency of these networks has become even more significant. Objects need reliable communications at suitable... 相似文献
5.
Imaging of the optic disc and retinal nerve fiber layer: the effects of age, optic disc area, refractive error, and gender. 总被引:3,自引:0,他引:3
Christopher Bowd Linda M Zangwill Eytan Z Blumenthal Cristiana Vasile Andreas G Boehm Parag A Gokhale Kourosh Mohammadi Payam Amini Timothy M Sankary Robert N Weinreb 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(1):197-207
We cross-sectionally examined the relationship between age, optic disc area, refraction, and gender and optic disc topography and retinal nerve fiber layer (RNFL) measurements, using optical imaging techniques. One eye from each of 155 Caucasian subjects (age range 23.0-80.8 y) without ocular pathology was included. Measurements were obtained by using the Heidelberg Retina Tomography (HRT), the GDx Nerve Fiber Analyzer, and the Optical Coherence Tomograph (OCT). The effects of age were small (R2 < 17%) and were limited to specific HRT, GDx, and OCT parameters. Disc area was significantly associated with most HRT parameters and isolated GDx and OCT parameters. Refraction and gender were not significantly associated with any optic disc or RNFL parameters. Although effects of age on the optic disc and RNFL are small, they should be considered in monitoring ocular disease. Optic disc area should be considered when cross-sectionally evaluating disc topography and, to a lesser extent, RNFL thickness. 相似文献
6.
Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants
in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also
an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication
and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the
integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a
collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability
framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications
facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate
different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability
requirements to support collaborative care delivery, particularly for asynchronous care delivery. 相似文献
7.
R. Zarei M. Amini S. M. Taheri A. H. Rezaei 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(1):165-174
In Classical Bayesian approach, estimation of lifetime data usually is dealing with precise information. However, in real
world, some informations about an underlying system might be imprecise and represented in the form of vague quantities. In
these situations, we need to generalize classical methods to vague environment for studying and analyzing the systems of interest.
In this paper, we propose the Bayesian estimation of failure rate and mean time to failure based on vague set theory in the
case of complete and censored data sets. To employ the Bayesian approach, model parameters are assumed to be vague random
variables with vague prior distributions. This approach will be used to induce the vague Bayes estimate of failure rate and
mean time to failure by introducing and applying a theorem called “Resolution Identity” for vague sets. In order to evaluate
the membership degrees of vague Bayesian estimate for these quantities, a computational procedure is investigated. In the
proposed method, the original problem is transformed into a nonlinear programming problem which is then divided into eight
subproblems to simplifying computations. 相似文献
8.
Barimani Samaneh Amini Amir Chaharmahali Iman 《Journal of Computational Electronics》2021,20(3):1332-1342
Wave absorbers are considered to be fundamental building blocks for the manipulation of light. Almost all optical systems exploit absorbers to realize some functions. A highly tunable wide-band THz absorber is presented herein. Utilizing a dual-bias scheme with a single graphene layer leads to greater freedom to control the absorption response, while a conventional periodic array of graphene ribbons and a layer of graphene sheet are also exploited. Also, a circuit model representation for all the constituent parts of the proposed absorber is developed with an evolved design methodology. According to the simulation results, wide-band absorption from 3.5 to 6 THz is achieved.
相似文献9.
Susana P. Alves Payam Vahmani Cletos Mapiye Tim A. McAllister Rui J. B. Bessa Michael E. R. Dugan 《Lipids》2021,56(6):539-562
Trans (t) fatty acids (TFA) from partially hydrogenated vegetable oils (i.e., industrial trans) have been phased out of foods in many countries due to their promotion of cardiovascular disease. This leaves ruminant-derived foods as the main source of TFA. Unlike industrial TFA where catalytic hydrogenation yields a broad distribution of isomers, ruminant TFA are enzymatically derived and can result in enrichment of specific isomers. Comparisons between industrial and ruminant TFA have often exonerated ruminant TFA due to their lack or at times positive effects on health. At extremes, however, ruminant-sourced foods can have either high levels of t10- or t11-18:1, and when considering enriched sources, t10-18:1 has properties similar to industrial TFA, whereas t11-18:1 can be converted to an isomer of conjugated linoleic acid (cis(c)9,t11-conjugated linoleic acid), both of which have potential positive health effects. Increased t10-18:1 in meat-producing ruminants has not been associated with negative effects on live animal production or meat quality. As such, reducing t10-18:1 has not been of immediate concern to ruminant meat producers, as there have been no economic consequences for its enrichment; nevertheless at high levels, it can compromise the nutritional quality of beef and lamb. In anticipation that regulations regarding TFA may focus more on t10-18:1 in beef and lamb, the present review will cover its production, analysis, biological effects, strategies for manipulation, and regulatory policy. 相似文献
10.
Engineering Transition Metal Layers for Long Lasting Anionic Redox in Layered Sodium Manganese Oxide
Natalia Voronina Jun Ho Yu Hee Jae Kim Najma Yaqoob Olivier Guillon Hyungsub Kim Min-Gi Jung Hun-Gi Jung Koji Yazawa Hitoshi Yashiro Payam Kaghazchi Seung-Taek Myung 《Advanced functional materials》2023,33(5):2210423
Oxygen-redox-based-layered cathode materials are of great importance in realizing high-energy-density sodium-ion batteries (SIBs) that can satisfy the demands of next-generation energy storage technologies. However, Mn-based-layered materials (P2-type Na-poor Nay[AxMn1−x]O2, where A = alkali ions) still suffer from poor reversibility during oxygen-redox reactions and low conductivity. In this work, the dual Li and Co replacement is investigated in P2-type-layered NaxMnO2. Experimentally and theoretically, it is demonstrated that the efficacy of the dual Li and Co replacement in Na0.6[Li0.15Co0.15Mn0.7]O2 is that it improves the structural and cycling stability despite the reversible Li migration from the transition metal layer during de-/sodiation. Operando X-ray diffraction and ex situ neutron diffraction analysis prove that the material maintains a P2-type structure during the entire range of Na+ extraction and insertion with a small volume change of ≈4.3%. In Na0.6[Li0.15Co0.15Mn0.7]O2, the reversible electrochemical activity of Co3+/Co4+, Mn3+/Mn4+, and O2-/(O2)n- redox is identified as a reliable mechanism for the remarkable stable electrochemical performance. From a broader perspective, this study highlights a possible design roadmap for developing cathode materials with optimized cationic and anionic activities and excellent structural stabilities for SIBs. 相似文献