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Modified Holographic Ricci Dark Energy in Chameleon Brans–Dicke Cosmology and Its Thermodynamic Consequence

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Communications in Theoretical Physics 2015年第4期63卷 453-458页

作者： A.Jawad S.Chattopadhyay S.Bhattacharya A.Pasqua Department of Mathematics,COMSATS institute of information technology Pailan College of Management and technology,B{4.al Pailan Park Department of Mathematics,Indian institute of engineering science and technology Department of Physics,University of Trieste abduljawad@ciitlahore.edu.pk jawadab181@*** surajcha@iucaa.ernet.in samarpita-sarbajna@yahoo.co.in toto.pasqua@*** Department of Physics University of Trieste Via Valerio 2 34127 Trieste Italy

The objective of this paper is to discuss the Chameleon Brans–Dicke gravity with non-minimally matter coupling of scalar field. We take modified Holographic Ricci dark energy model in this gravity with its energy density in interaction with energy density of cold dark matter. We assume power-law ansatz for scale factor and scalar field to discuss potential as well as coupling functions in the evolving universe. These reconstructed functions are plotted versus scalar field and time for different values of power component of scale factor n. We observe that potential and coupling functions represent increasing behavior, in particular, consistent results for a specific value of n. Finally, we have examined validity of the generalized second law of thermodynamics and we have observed its validity for all values of n.

关键词： Chameleon Brans–Dicke gravity holographic dark energy scalar field

Bolstering functionality in multilayer and bilayer WS2 via focused laser micro-engraving

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science china(information sciences) 2023年第6期66卷 94-101页

作者： Si Min CHAN eng Tuan POH Jin Feng LEONG Kuan eng Johnson GOH Chorng Haur SOW Department of Physics National University of Singapore institute of Materials Research and engineering Agency for ScienceTechnology and Research (A~*STAR) Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological University

Laser thinning of multilayer transition metal dichalcogenide(TMD)crystals has long been explored for its potential to produce localized domains of optically functional monolayers. Despite the high spatial control and resolution of the laser, the range of appropriate applications for these laser-thinned domains is still limited by the peripheral regions of unaltered thick multilayers. Herein, we report a newfound property of the laser-thinned regions to adhere strongly to the underlying substrate when lasered down to the monolayer limit. Upon a brief sonication in various solvents, the surrounding pristine multilayers can be lifted off, solely leaving behind the post-lasered monolayer patterns. Coupled with the flexible maneuver of the laser, various monolayer designs can be achieved, including micro-antenna, waveguide, and electrode geometries with lateral line widths at 1.5 μm resolution. Furthermore, we also detail the optical properties of the monolayers obtained from laser thinning, with those acquired from multilayers containing more defectbound excitons, whereas those lasered from bilayers presenting a trion-dominated profile similar to as-grown monolayers. Together, these findings allow for faster and more efficient multilayer removal and areal shaping of optically active monolayer domains, in comparison to multistep and complex standard lithographic etching(lithography–etch–develop)procedures.

关键词： WS$_2$ monolayer micro-patterning focused laser sonication lift-off

Differentiation transforming system

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Progress in Natural science:Materials International 2009年第3期19卷 397-406页

作者： Qiang Chenga,b,c,*, Haibin Zhang d, Bin Wanga, Yonghua Zhao c a LASG, institute of Atmospheric Physics, Chinese Academy of sciences, Beijing 100029, PR china b LSEC, institute of Computing Mathematics, Chinese Academy of sciences, Beijing 100080, PR china c sc, institute of Computer Network information Center, Chinese Academy of sciences, Beijing 100190, PR china d College of Applied sciences, Beijing University of technology, Beijing 100124. PR china [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 PR China [b]LSEC Institute of Computing Mathematics Chinese Academy of Sciences Beijing 100080 PR China [c]SC Institute of Computer Network Information Center Chinese Academy of Sciences Beijing 100190 PR China [d]College of Applied Sciences Beijing University of Technology Beijing 100124 PR China

The differentiation transforming (DFT) system is developed to produce the tangent linear codes, which is used to calculate the Jaco- bian- and the Hessian-vector products with no truncation errors. This paper first gives the introduction of the functionality and features of the DFT system, and then discusses several techniques for the implementation of automatic differentiation tools, including data depen- dence analysis, singular differentiation and code optimization. Finally, the codes generated with DFT used in several applications have been demonstrated.

关键词： Jacobian Hessian Tangent linear model Automatic differentiation

Can two-dimensional graphdiyne-based materials be novel materials for perovskite solar cell applications?

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Materials Futures 2023年第2期2卷 142-151页

Two-dimensional(2D)graphdiyne(GDY)-based materials have attracted attention in the solar cell research community owing to their unique physicochemical properties and hydrophobic nature which can serve as moisture resistance from the surrounding *** from these,the performance and stability ofperovskite solar cells(Pscs)can be greatly improved via the addition of 2D GDY-based *** mini-review summarizes the recent development of 2D GDY-based materials for Psc *** roles of 2D GDY-based materials,such as hole transporting material,electron transporting material,dopant material in perovskite film and interfacial layer,are discussed in ***,we provide future perspectives in this field,aiming to help further progress efficient and stable 2D GDY-based materials in Pscs.

关键词： two-dimensional material graphdiyne perovskite solar cells power conversion efficiency stability

Influence of p-layer on the performance of n-i-p μc-Si:H thin film solar cells

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2042-2046页

作者： YUAN YuJie 1,2,ZHANG KaiLiang 1,2,WEI Zhen 1,2 & Geng XinHua 3 1 College of Electronics information engineering,Tianjin University of technology,Tianjin 300384.{4. 2 Tianjin Key Laboratory of Film Electronic and Communication Devices,Tianjin University of technology,Tianjin 300384.{4. 3 institute of Photo-Electronics Thin Film Devices and Technique,Nankai University,Tianjin 300071,{4. 1. College of Electronics information engineering Tianjin University of Technology Tianjin 300384 China2. Tianjin Key Laboratory of Film Electronic and Communication Devices Tianjin University of Technology Tianjin 300384 China3. Institute of Photo-Electronics Thin Film Devices and Technique Nankai University Tianjin 300071 China

The high pressure radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) process was adopted to prepare the n-i-p microcrystalline silicon solar cells,the influence of p-type layers on the performance of the solar cells was investigated,and the optimum p layer suited to the n-i-p microcrystalline silicon solar cells was *** experimental results demonstrate that the performance of the solar cells can be highly affected by the structural and optical properties of the p-layers,and the performance of solar cells can be greatly improved by optimizing p *** have achieved an initial active-area efficiency of 8.17% (V oc =0.4. V,J sc =24.9 mA/cm 2 ,FF=67%) for the μc-Si:H single-junction n-i-p solar cells and an initial active-area efficiency of 10.93% (V oc =1.31 V,J sc =13.09 mA/cm 2 ,FF=64.) for the a-Si:H/μc-Si:H tandem n-i-p solar cells.

关键词： microcrystalline silicon solar cells quantum confinement effect p-type layers

A NEW UEP scHEME FOR ROBUST VIDEO TRANSMISSION IN LDPC CODED MIMO-OFDM SYSTEM

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Journal of Electronics(china) 2007年第3期24卷 396-401页

作者： Ru Congchong Zheng Haifeng Yin Liuguo Lu Jianhua Chen Changwen Department of Electronic engineering Tsinghua University Beijing 100084 China College of information technology Fuzhou University Fuzhou 350002 China Dept. Electrical ＆ Computer eng. Florida Institute of Technology Melbourne FL 32040 USA

In order to improve the video transmission performance in Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing （MIMO-OFDM） system, a new scheme, which integrates Multiple Description Coding （MDC）, Low Density Parity Check （LDPC） coding and hybrid space time coding, is proposed in this letter. In particular, a hybrid space time coding algorithm is combined with LDPC codes to perform Unequal Error Protection （UEP） of MDC encoded video streams. Comparing with the UEP transmission with only LDPC codes, the proposed scheme achieves more than ldB gain in terms of Signal to Noise Ratio （SNR） when the Peak Signal to Noise Ratio （PSNR） of reconstructed video is above 30dB.

关键词： Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) Multiple Description Coding (MDC) Low Density Parity Check (LDPC) Unequal Error Protection (UEP)

GPC Method In Segment of Chinese Continuous Sentence

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GPC Method In Segment of Chinese Continuous Sentence

Randomly Generating Four Mixed Bell-Diagonal States with a Concurrences Sum to Unity

2002年第6届信号处理国际会议

作者： Fan Jing Liu Huihua Sun HaiDept. of information & Communication eng. Beijing information technology {4.

＜正＞ In this paper, a new method for recognizing the start and the end of each word in a Chinese continuous sentence is discussed. We define a new recognition character called Periodic Gradual Change （PGC）. A continuous speech sentence can be separated into many single words with a combined new method of PGC and other characters such as Zero Crossing Rate （ZCR）, instantaneous swing（E character） and Linear Predictive Coding（LPC） parameter. By new method the recognition rate for continuous speech segment is improved.

关键词： PGC ZCR E character LPC

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Chinese Physics Letters 2012年第1期29卷 24-27页

作者： S.P.Toh Hishamuddin Zainuddin Kim eng Foo Faculty of engineering The University of Nottingham Malaysia CampusJalan Broga43500 SemenyihSelangor Darul EhsanMalaysia Laboratory of Computational sciences and Mathematical Physics Institute for Mathematical ResearchUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Physics Faculty of ScienceUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Faculty of Health and Life sciences INTI International UniversityPersiaran Perdana BBNPutra Nilai71800 NilaiNegeri SembilanMalaysia

A two-qubit system in quantum information theory is the simplest bipartite quantum system and its concurrence for pure and mixed states is well *** a subset of two-qubit systems,Bell-diagonal states can be depicted by a very simple geometrical representation of a tetrahedron with sides of length 2√*** on this geometric representation,we propose a simple approach to randomly generate four mixed Bell decomposable states in which the sum of their concurrence is equal to one.

关键词： quantum concurrence representation

Optimum spectral band design of the night vision system based on MRC

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Optimum spectral band design of the night vision system base...