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Regional-scale study on sediment Processes of Khuran strait at Persian Gulf with Implications for Engineering Design

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China Ocean Engineering 2019年第3期33卷 356-364页

作者： A. shanehsazzadeh h. Ardalan Faculty of Civil Engineering and Transportation University of Isfahan Isfahan Iran Water Research Institute (WRI) Tehran Iran

In this article, the sediment transport processes in the Khuran strait between the mainland Iran and Qeshm Island at North Central Persian Gulf are studied in regional scale in a comprehensive manner. The objectives of this study include defining the type and origin of the sediment, the influencing factors, and the dominant mode of sediment transport. Four possible scenarios of sediment processes in terms of sediment sources and influential environmental forces are examined. The results of the conceptual and 2D numerical model of mIKE21 applied for this purposes indicate that the sediment sources in the transport processes are mainly provided by the sediments suspended from the central and eastern zones of the strait bed. Other sources including input from rivers do not have direct influence on the processes. The results are applied to the study of morphological changes for engineering applications including the pattern and amount of deposit in the Rajaee port approach channel and harbor basin. The pattern and amount of annual sediment deposits in the approach channel predicted by the model is satisfactory, compatible with annual dredging records.

关键词： sediment transport morphodynamics 2D numerical model Persian Gulf Khuran strait Rajaee Port

A novel approach to determine residual stress field during FsW of AZ91 mg alloy using combined smoothed particle hydrodynamics/neuro-fuzzy computations and ultrasonic testing

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Journal of magnesium and Alloys 2021年第4期9卷 1311-1335页

作者： A.R.Eivani h.Vafaeenezhad h.R.Jafarian J.Zhou school of metallurgy and materials engineering iran university of science and technology^nartnaktehraniran department of biomechanical engineering delft university of technologymekehveg 22628 cd delftthe netherlands

The faults in welding design and process every so often yield defective parts during friction stir welding(FsW).The development of numerical approaches including the finite element method(FEm)provides a way to draw a process paradigm before any physical *** is not practical to simulate all possible designs to identify the optimal FsW practice due to the inefficiency associated with concurrent modeling of material flow and heat dissipation throughout the *** study intends to develop a computational workflow based on the mesh-free FEm framework named smoothed particle hydrodynamics(sPh)which was integrated with adaptive neuro-fiizzy inference system(ANFIs)to evaluate the residual stress in the FsW *** integrated sPh and ANFIs methodology was established and the well-trained ANIs was then used to predict how the FsW process depends on its *** verify the sPh calculation,an itemized FsW case was performed on AZ91 mg alloy and the induced residual stress was measured by ultrasonic *** suggested methodology can efficiently predict the residual stress distribution throughout friction stir welding of AZ91 alloy.

关键词： Friction stir welding(FsW) smoothed particle hydrodynamics(sPh) Adaptive neuro-fuzzy inference system(ANFIs) Ultrasonic Residual stress

Experimental investigations of the functional morphology of dragonfly wings

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Chinese Physics B 2013年第8期22卷 738-745页

作者： h. Rajabi A. Darvizeh Department of mechanical Engineering Faculty of Engineering The University of GuilanRasht Iran

Nowadays, the importance of identifying the flight mechanisms of the dragonfly, as an inspiration for designing flapping wing vehicles, is well known. An experimental approach to understanding the complexities of insect wings as organs of flight could provide significant outcomes for design purposes. In this paper, a comprehensive investigation is carried out on the morphological and microstructural features of dragonfly wings. scanning electron microscopy （sEm） and tensile testing are used to experimentally verify the functional roles of different parts of the wings. A number of sEm images of the elements of the wings, such as the nodus, leading edge, trailing edge, and vein sections, which play dominant roles in strengthening the whole structure, are presented. The results from the tensile tests indicate that the nodus might be the critical region of the wing that is subjected to high tensile stresses. Considering the patterns of the longitudinal corrugations of the wings obtained in this paper, it can be supposed that they increase the load-bearing capacity, giving the wings an ability to tolerate dynamic loading conditions. In addition, it is suggested that the longitudinal veins, along with the leading and trailing edges, are structural mechanisms that further improve fatigue resistance by providing higher fracture toughness, preventing crack propagation, and allowing the wings to sustain a significant amount of damage without loss of strength.

关键词： dragonfly wings sEm tensile test nodus longitudinal corrugation

schrodinger Equation for an Open system

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Chinese Physics Letters 2002年第9期19卷 1238-1243页

作者：毕桥 h.E.Ruda ComplexityscienceCenter YangzhouUniversityYangzhou225002 EnergeniusCentreforAdvancednanotechnology UniversityofTorontoTorontoM5S3E4Canada

We present a schrödinger (Liouville) type of equation for a quantum open system. It has a correlated part, and various master equations may be its special cases. It also has significant applications for constructing decoherence-free subspace for quantum computation. It is related to the original schrödinger (Liouville) equation for the total system through a non-unitary similarity transformation. It is unnecessary for its correlated part to be self-adjoint, so there is a complex spectrum for the corresponding hamiltonian (Liouvillian), which enables the time evolution of states to be asymmetric. This shows just the correlation to produce evolution of world.

关键词： Liouville equation

An efficient rate control algorithm for JPEG2000 based on reverse order

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Journal of Central south University 2017年第6期24卷 1396-1405页

作者： A.Etesaminia A.h.mazinan Department of electronics Engineering South Tehran BranchIslamic Azad University(IAU)No.209North Iranshahr StP.O.Box 11365/4435TehranIran Department of Control Engineering Faculty of Electrical EngineeringSouth Tehran BranchIslamic Azad University(IAU)No.209North Iranshahr StP.O.Box 11365/4435TehranIran

The JPEG2000 image compression standard is the powerful encoder which can provide phenomenal rate-control performance. The post-compression rate-distortion(PCRD) algorithm in JPEG2000 is not efficient. It requires encoding all coding passes even though a large contribution of them will not be contained in the final code-stream. Tier-1 encoding in the JPEG2000 standard takes a significant amount of memory and coding time. In this work, a low-complexity rate distortion method for JPEG2000 is proposed. It is relied on a reverse order for the resolution levels and the coding passes. The proposed algorithm encodes only the coding passes contained in the final code-stream and it does not need any post compression rate control part. The computational complexity of proposed algorithm is negligible, making it suitable to compression and attaining a significant performance. simulations results show that the proposed algorithm obtained the PsNR values are comparable with the optimal PCRD.

关键词： image coding JPEG2000 post compression rate distortion (PCRD) rate control

Co-crystals of non-steroidal anti-inflammatory drugs(NsAIDs):Insight toward formation,methods,and drug enhancement

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Particuology 2021年第5期19卷 227-241页

作者： Andre L.C.s.Nascimento Richard P.Fernandes maxime D.Charpentier Joop h.ter horst Flavio J.Caires marius Chorilli sao Paulo state University(UNEsP) School of Pharmaceutical Sciences14800-903 AraraquaraSao PauloBrazil são Paulo state University(UNEsP) Institute of Chemistry14800-060 AraraquaraSao PauloBrazil EPsRC Centre for Innovative manufacturing in Continuous manufacturing and Crystallisation University of StrathclydeGlasgowUK sao Paulo state University(UNEsP) School of Sciences17033-260 BauruSao PauloBrazil

Pharmaceutical co-crystals have been explored by many researchers as a strategy to optimize physicochemical properties of solid-state *** improvements of solubility,bioavailability,and the reduced tendency for phase transformation occurrence,are factors that highlight benefits of pharmaceutical co-crystals among other solid *** to the Biopharmaceutical Classification system(BCs),non-steroidal anti-inflammatory drugs(NsAIDs)are class Ⅱ drugs,which have low aqueous solubility and therefore co-crystallization has the potential to optimize NsAID product *** this review,we highlight the recent progress made on NsAIDs co-crystals,their co-formers,synthesis,methods and use,while we underline some promising results on in vitro and in vivo co-crystal properties.A celecoxib-tramadol co-crystal reaches phase Ⅲ clinical trials,showing greater analgesic activity than both individual *** aqueous solubility of the co-crystal formed between l-proline and diclofenac is very high in comparison with the pure *** co-crystals with urea and thiourea have an increase of drug release of almost 60%.Co-crystal design brings a new perspective in drug development since the co-former used can also be a biologically active component allowing to combine different anti-inflammatory drugs,which have an incredible spectrum of application due to the analgesic,anti-pyretic and anti-inflammatory properties.

关键词： Pharmaceutical co-crystals NsAIDs supramolecular synthons Co-crystal discovery Bioavailability

Temperature-Responsive Tensile Actuator Based on multi-walled Carbon Nanotube Yarn

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Nano-micro Letters 2016年第3期8卷 254-259页

作者： hyunsoo Kim Jae Ah Lee hyeon Jun sim márcio D.Lima Ray h.Baughman seon Jeong Kim Center for self-powered Actuation and Department of Biomedical Engineering Hanyang University The Alan G.mac Diarmid Nano Tech Institute University of Texas at Dallas

many temperature indicators or sensors show color changes for materials used in food and medical ***, they are not helpful for a color-blind person or children who lack judgment. In this paper, we introduce simply fabricated and more useful low-temperature indicator(~30 °C) for devices that actuates using paraffin-infiltrated multiwalled carbon nanotube(mWCNT) coiled yarn. The density difference of mWCNT yarn provides large strain(~330 %)when heat causes the melted polymer to move. Furthermore, the mWCNT yarn decreases the melting point of *** properties allow control of the actuating temperature. In addition, mechanical strength was enhanced by mWCNT than previously reported temperature-responsive actuators based on shape memory polymers. This simply fabricated temperature indicator can be applied in latching devices for medical and biological fields.

关键词： Time–temperature Actuator Carbon nanotube Paraffin Coiled yarn Dual-Archimedean

Cloning and characterization of a FLORICAULA/LEAFY ortholog, PFL, in polygamous papaya

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Cell Research 2005年第8期15卷 576-584页

作者： Paul h. mOORE,henrik h. ALBERT,Adrienne h.K. ROADER,Ray mING UsDA-ARs Pacific Basin Agricultural Research Center Aiea hI 96701 UsA UsDA-ARs Pacific Basin Agricultural Research Center Aiea hI 96701 UsA section of Cell and Developmental Biology University of California san Diego La Jolla CA 92093 UsA hawaii Agriculture Research Center Aiea hI 96701 UsA

The homologous genes FLORICAULA (FLO) in Antirrhinum and LEAFY (LFY) in Arabidopsis are known to regu- late the initiation of flowering in these two distantly related plant species. These genes are necessary also for the expression of downstream genes that control floral organ identity. We used Arabidopsis LFY cDNA as a probe to clone and sequence a papaya ortholog of LFY, PFL. It encodes a protein that shares 61% identity with the Arabidopsis LFY gene and 71% identity with the LFY homologs of the two woody tree species: California sycamore (Platanus racemosa) and black cottonwood (Populus trichocarpa). Despite the high sequence similarity within two conserved regions, the N-terminal proline-rich motif in papaya PFL differs from other members in the family. This difference may not affect the gene function of papaya PFL, since an equally divergent but a functional LFY ortholog NEEDLY of Pinus radiata has been reported. Genomic and BAC southern analyses indicated that there is only one copy of PFL in the papaya genome. In situ hybridization experiments demonstrated that PFL is expressed at a relatively low level in leaf primordia, but it is expressed at a high level in the floral meristem. Quantitative PCR analyses revealed that PFL was expressed in flower buds of all three sex types - male, female, and hermaphrodite with marginal difference between hermaphrodite and unisexual flowers. These data suggest that PFL may play a similar role as LFY in flower development and has limited effect on sex differentiation in papaya.

关键词： divergence floral meristem identity gene flower development gene expression molecular phylogeny.

Analytical modelling of end thermal coupling in a solid-state laser longitudinally bonded by a vertical-cavity top-emitting laser diode

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Chinese Physics B 2009年第11期18卷 4912-4918页

作者：吴坚 h.D.summers school of Physics Beijing University of Aeronautics and Astronautics school of Physics and Astronomy Cardiff University

The intrinsic features involving a circularly symmetric beam profile with low divergence, planar geometry as well as the increasingly enhanced power of vertical-cavity surface-emitting lasers （VCsels） have made the VCsel a promising pump source in direct end bonding to a solid-state laser medium to form the minimized, on-wafer integrated laser system. This scheme will generate a surface contact pump configuration and thus additional end thermal coupling to the laser medium through the joint interface of both materials, apart from pump beam heating. This paper analytically models temperature distributions in both VCsel and the laser medium from the end thermal coupling regarding surface contact pump configuration using a top-emitting VCsel as the pump source for the first time. The analytical solutions are derived by introducing relative temperature and mean temperature expressions. The results show that the end contact heating by the VCsel could lead to considerable temperature variations associated with thermal phase shift and thermal lensing in the laser medium. however, if the central temperature of the interface is increased by less than 20 K, the end contact heating does not have a significant thermal influence on the laser medium. In this case, the thermal effect should be dominated by pump beam heating. This work provides useful analytical results for further analysis of hybrid thermal effects on those lasers pumped by a direct VCsel bond.

关键词： solid-state laser end pump thermal coupling vertical-cavity surface-emitting laser