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排序方式: 共有274条查询结果,搜索用时 31 毫秒
1.
Zia Muhammad Yousuf Irfan Otero Pablo Siddiqui Atif Poncela Javier 《Wireless Personal Communications》2021,116(2):1171-1193
Wireless Personal Communications - Underwater Wireless Sensor Networks (UWSNs) are playing a vital role in exploring the unseen underwater (UW) natural resources. However, performance evaluation of... 相似文献
2.
Aishani Mazumder Chung Kim Nguyen Thiha Aung Mei Xian Low Md. Ataur Rahman Salvy P. Russo Sherif Abdulkader Tawfik Shifan Wang James Bullock Vaishnavi Krishnamurthi Nitu Syed Abhishek Ranjan Ali Zavabeti Irfan H. Abidi Xiangyang Guo Yongxiang Li Taimur Ahmed Torben Daeneke Akram Al-Hourani Sivacarendran Balendhran Sumeet Walia 《Advanced functional materials》2023,33(36):2303641
Miniaturization and energy consumption by computational systems remain major challenges to address. Optoelectronics based synaptic and light sensing provide an exciting platform for neuromorphic processing and vision applications offering several advantages. It is highly desirable to achieve single-element image sensors that allow reception of information and execution of in-memory computing processes while maintaining memory for much longer durations without the need for frequent electrical or optical rehearsals. In this work, ultra-thin (<3 nm) doped indium oxide (In2O3) layers are engineered to demonstrate a monolithic two-terminal ultraviolet (UV) sensing and processing system with long optical state retention operating at 50 mV. This endows features of several conductance states within the persistent photocurrent window that are harnessed to show learning capabilities and significantly reduce the number of rehearsals. The atomically thin sheets are implemented as a focal plane array (FPA) for UV spectrum based proof-of-concept vision system capable of pattern recognition and memorization required for imaging and detection applications. This integrated light sensing and memory system is deployed to illustrate capabilities for real-time, in-sensor memorization, and recognition tasks. This study provides an important template to engineer miniaturized and low operating voltage neuromorphic platforms across the light spectrum based on application demand. 相似文献
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Irfan Ahmad Rather Gulshan Kumar Rahul Saha 《International Journal of Communication Systems》2023,36(9):e5473
In heterogeneous access network, Multiple-Input Multiple-Output (MIMO) radio-over-fiber (RoF) system is an efficient approach for multiple signal transmission with low cost and complexity. The performance of RoF fronthaul system in MIMO system will be varied with different nonlinear effects. By adjusting various transmission parameters, such as the input signal power or the laser bias current, the nonlinear impacts produced by the RoF system can be reduced. In this paper, a novel algorithm Improved Aquila Optimization (IAO) is proposed to optimize transmission circumstances of MIMO RoF system. It determines the appropriate bias current for both lasers and Radio Frequency (RF) signal power in a short period. The input signals are wavelength multiplexed with Intensity Modulation and Direct Detection (IM/DD) applied. The carrier as well as transmission frequency is governed by the MIMO-Long-Term Evolution (LTE) standard. The proposed system is implemented in MATLAB, and the performance is evaluated. The experimental results show that fast convergence and trade-off between noise and nonlinearity are obtained with varying bandwidth. In the experimental scenario, the maximum Error Vector Magnitude (EVM) of 1.88, 3.14, and signal-to-noise ratio (SNR) of 3.204, and 2.698 was attained for both quadrature phase shift keying (QPSK) and quadrature amplitude modulation (QAM) modulation. [Correction added on 24 April 2023, after first online publication: the SNR values were corrected in the preceding sentence.] For 100 iterations, the processing time was reduced to 0.137 s. When compared with the conventional state-of-the-art approaches, the accuracy and computational complexity of the proposed approach are improved. 相似文献
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Wireless Personal Communications - Mobile edge computation (MEC) is a potential technology to reduce the energy consumption and task execution delay for tackling computation-intensive tasks on... 相似文献
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Atta-ur-Rahman Nasim S Baig I Sener B Orhan I Ayanoglu F Choudhary MI 《Natural product research》2004,18(5):465-471
Two new isoflavones 1 and 2 along with eleven known compounds 3-13, have been isolated for the first time from the rhizomes of Iris soforana. The structures of these compounds were determined on the basis of spectroscopic methods and found to be 5,3'-dihydroxy-4'-methoxy-6,7-methylenedioxyisoflavone (1) (Soforanarin A), and 5,7,5'-trimethoxy-6,3',4'-trihydroxyisoflavone (2) (Soforanarin B). 相似文献
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Solubility of drugs in aqueous media is a real issue for scientists and a lot of work is going on to resolve the issue. The same is the case for ibuprofen, which is a derivative of propionic acid, belongs to the NSAIDs family and has low solubility in pure water. Therefore, its solubility has been investigated in dimethyl dodecyl ammonium-propane sulfonate, DDAPS, micellar solution, DDAPS/butanol mixtures and in various (hexane, decane and tetradecane) oil-in-water microemulsions to find out a suitable vehicle. The aggregation number, size and flow ability of micelles and microemulsions were estimated using refractive index, viscosity and light scattering measurements. It has been observed that these microemulsions have a higher ability to solubilize ibuprofen than DDAPS/butanol mixtures or DDAPS micelles. 相似文献
9.
Development and validation of an LC‐MS/MS method for simultaneous quantitative analysis of free and conjugated bisphenol A in human urine 下载免费PDF全文
Dilek Battal Ismet Cok Irfan Unlusayin Bahar Tunctan 《Biomedical chromatography : BMC》2014,28(5):686-693
Bisphenol A (BPA) is an environmental endocrine‐disrupting chemicals that is widely used in common consumer products. There is an increasing concern regarding human exposure to BPA owing to the potential adverse effects associated with its estrogenic activity. For assessing environmental exposure to BPA, it is essential to have a sensitive, accurate and selective analytical method, especially one that can detect low BPA levels in complex sample matrices. In this study, we developed and validated an accurate, sensitive, and robust liquid chromatography–tandem mass spectrometry method for simultaneous quantification of free BPA and BPA β‐d ‐glucuronide (BPA‐gluc) concentrations in human urine with only a single injection. Calibration curves were linear over a concentration range of 1–100 ng/mL for BPA and 10–1000 ng/mL for BPA‐gluc. The levels of the analytes were determined quantitatively with HPLC/ESI‐MS/MS by using negative electrospray ionization in the select ion monitoring mode and a pentaflouraphenyl propyl column. The validated method was applied to the analysis of spot urine specimens collected from randomly selected healthy human subjects. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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