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Acta Metallurgica sinica(English Letters) 2007年第2期20卷 111-116页

作者： Z.C. Guo X.y. Zhu R.D. Xu Faculty of Materials and Metallurgical Engineering Kunming University of Science and Technology Kunming 650093 China

The effects of pulse frequency f and duty cycle r on the deposition rate, composition, morphology, and hardness of pulse electrodeposited RE （rare earth）-Ni-W-P-siC composite coatings have been studied. The results indicate that pulse current can improve the deposition rate of RE-Ni-W-P-siC composite coatings; W, P, and siC contents in the coating decrease with the increase of pulse frequency and reach the lowest value at f = 33Hz, whereas the RE content in the composite coatings increases with the increase of pulse frequency. siC content decreases with the increase of duty cycle, W content reaches the lowest value, and P content reaches the highest value at r = 0.4; pulse current and RE can lead to smaller size of the crystalline grains; however, the effects of different pulse frequency and duty cycle on the morphologies of RE-Ni-W-P-siC composite coatings are not obvious. The hardness of RE-Ni-W-P-siC composite coatings is the highest when the duty cycle is at 0.6 and 0.8 and pulse frequency is at 50Hz. At the same pulse frequency, the hardness of RE-Ni-W-P-siC composite coatings at r= 0.8 is higher than that at r= 0.6.

关键词： frequency duty cycle electrodeposition RE-Ni-W-P-siC composite coating

Convolutional Neural Networks for Automated Diagnosis of Diabetic Retinopathy in Fundus Images

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Journal of Artificial Intelligence and Technology 2023年第4期3卷 205-214页

作者： s.Rama Krishna Naresh Cherukuri y.Dileep Kumar R.Jayakarthik B.Nagarajan Allam Balaram G.Divya Jyothi Department of Computer science&Engineering GSoTGITAM(Deemed-to-be-University)HyderabadIndia Department of Computer science and Engineering Prasad V.Potluri Siddhartha Institute of Technology(Autonomous)VijayawadaIndia Department of Electronics&Communication Engineering School of EngineeringMohan Babu UniversityTirupatiAndhra PradeshIndia Department of Computer science Saveetha College of Liberal Arts and Sciences SIMATSIndia Department of Computer science and Engineering KPR Institute of Engineering and TechnologyCoimbatoreIndia Department of Computer science and Engineering MLR Institute of TechnologyHyderabadIndia Department of Computer science and Engineering MLR Institute of TechnologyDundigalMedchalTelanganaIndia

Diabetic retinopathy(DR),a long-term complication of diabetes,is notoriously hard to detect in its early stages due to the fact that it only shows a subset of *** diagnostic procedures for DR now include optical coherence tomography and digital fundus *** digital fundus images alone could provide a reliable diagnosis,then eliminating the costly optical coherence tomography would be beneficial for all parties *** and their patients will find this *** deep convolutional neural networks(DCNNs),we provide a novel approach to this *** approach deviates from standard DCNN methods by exchanging typical max-pooling layers with fractional max-pooling *** order to collect more subtle information for categorization,two such DCNNs,each with a different number of layers,are *** establish these limits,we use DCNNs and features extracted from picture metadata to train a support vector machine *** our experiments,we used information from Kaggle’s open DR detection *** fed our model 34,124 training images,1,000 validation examples,and 53,572 test images to train and test *** of the five classes in the proposed DR classifier corresponds to one of the steps in the DR process and is given a numeric value between 0 and *** results show a higher identification rate(86.17%)than those found in the existing literature,indicating the suggested strategy may be *** have jointly developed an algorithm for machine learning and accompanying software,and we’ve named it deep *** of the fundus acquired by the typical person using a portable ophthalmoscope may be instantly analyzed using our *** technology might be used for self-diagnosis,at-home care,and telemedicine.

关键词： automated diagnosis of diabetic retinopathy DCNNs diabetic retinopathy self-diagnosis

A Compact self-Isolated MIMo Antenna system for 5G Mobile Terminals

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Computer systems science & Engineering 2022年第9期42卷 919-934页

作者： Muhannad y.Muhsin Ali J.salim Jawad K.Ali Microwave Research Group Department of Electrical EngineeringUniversity of TechnologyBaghdad10001Iraq Microwave Research Group Department of Communication EngineeringUniversity of TechnologyBaghdad10001Iraq

A compact self-isolated Multi Input Multi output (MIMo) antennaarray is presented for 5G mobile phone devices. The proposed antenna systemis operating at the 3.5 GHz band (3400–3600 MHz) and consists of eight antennaelements placed along two side edges of a mobile device, which meets the currenttrend requirements of full-screen smartphone devices. Each antenna element isdivided into two parts, a front part and back part. The front part consists of anI-shaped feeding line and a modified Hilbert fractal monopole antenna, whereasthe back part is an L-shaped element shorted to the system ground by a0.5 mm short stub. A desirable compactness can be obtained by utilizing the Hilbert space-filling property where the antenna element’s overall planar size printedon the side-edge frame is just (9.57 mm × 5.99 mm). The proposed MIMo antenna system has been simulated, analyzed, fabricated and tested. Based on the selfisolated property, good isolation (better than 15 dB) is attained without employingadditional decoupling elements and/or isolation techniques, which increases system complexity and reduces the antenna efficiency. The scattering parameters,antenna efficiencies, antenna gains, and antenna radiation characteristics areinvestigated to assess the proposed antenna performance. For evaluating the proposed antenna array system performance, the Envelope Correlation Coefficients(ECCs), Mean Effective Gains (MEGs) and channel capacity are *** antenna and MIMo performances are evaluated to confirm the suitability of the proposed MIMo antenna system for 5G mobile terminals.

关键词： 5G applications compact antennas isolation techniques MIMo antennas mobile terminals self-isolated antennas

Liver as a target of human immunodeficiency virus infection

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World Journal of Gastroenterology 2018年第42期24卷 4728-4737页

作者： Murali Ganesan Larisa y Poluektova Kusum K Kharbanda Natalia A osna Research service Veterans Affairs Nebraska-Western Iowa Health Care System Department of Internal Medicine University of Nebraska Medical Center Department of Pharmacology and Experimental Neuroscience University of Nebraska Medical Center

Liver injury is a characteristic feature of human immunodeficiency virus(HIV) infection, which is the second most common cause of mortality in HIV-infected patients. Now it is recognized that liver plays a key role in HIV infection pathogenesis. Antiretroviral therapy(ART), which suppresses HIV infection in permissive immune cells, is less effective in hepatocytes, thereby making these cells a silent reservoir of HIV infection. In addition to direct hepatotoxic effects of HIV, certain ART treatment modalities provide hepatotoxic effects. The exact mechanisms of HIV-triggered chronic hepatitis progression are not elucidated, but the liver is adversely affected by HIV-infection and liver cells are prominently involved in HIV-elicited injury. These effects are potentiated by second hits like alcohol. Here, we will focus on the incidence of HIV, clinical evidence of HIVrelated liver damage, interactions between HIV and liver cells and the role of alcohol and co-infection with hepatotropic viruses in liver inflammation and fibrosis progression.

关键词： Liver cells Antiretroviral therapy Apoptosis Inflammation Fibrosis Immunodeficiency virus Alcohol

Bell Polynomial Approach for the solutions of Fredholm Integro- Differential Equations with Variable Coefficients

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Computer Modeling in Engineering & sciences 2020年第6期123卷 973-993页

作者： Gökçe yıldız Gültekin Tınaztepe Mehmet sezer Department of Mathematics Faculty of ScienceManisa Celal Bayar UniversityManisaTurkey Vocational school of Technical sciences Akdeniz UniversityAntalyaTurkey

In this article,we approximate the solution of high order linear Fredholm integro-differential equations with a variable coefficient under the initial-boundary conditions by Bell *** collocation points and treating the solution as a linear combination of Bell polynomials,the problem is reduced to linear system of equations whose unknown variables are Bell *** solution to this algebraic system determines the approximate *** estimation of approximate solution is *** examples are provided to illustrate the performance of the *** numerical results are compared with the collocation method based on Legendre polynomials and the other two methods based on Taylor *** is observed that the method is better than Legendre collocation method and as accurate as the methods involving Taylor polynomials.

关键词： Bell polynomials collocation points matrix method Fredholm integrodifferential equations.

MICRosTRUCTURAL sTUDy oF Fe-Cr-Al/Al CoMPosITE CoATINGs DURING oXIDATIoN AND sULFIDATIoN AT 900℃

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Acta Metallurgica sinica(English Letters) 2007年第2期20卷 87-94页

作者： Z.L. Zhang D.y. Li X.Q. Dong school of Material science and Engineering Shenyang University of Technology Shenyang 110023 China

The microstructure of a composite coating system, which was composed of an inner layer of Fe-Cr-Al and an outer layer of aluminum, was studied after it was respectively oxidized and sulfurdized at elevated temperatures. Apart from the Al2o3 scale formed on the surface, the microstructure of the composite coatings exposed at 900℃ in air for 4h was a three-layer structure. The first layer consisted of a solid solution of Cr and Fe in α aluminum and an intermetallic compound FeAl3 while the second layer was a single phase of the aluminide and the third layer still remained the same appearance as the original Fe-Cr-Al coating. The microstructural observation of the specimen tested at 850-900℃ at low oxygen pressure and high sulfur pressure for 576h revealed that the surface coatings of the specimen had transformed into a duplex structure containing an outer layer and a thicker aluminide layer beneath. X-ray diffraction results showed that the out layer was composed of Al2s3 and Al2o3 and that AlCrFee was the main phase composition of the aluminide layer, with a few of Al2s3 and Al2o3 accompanied.

关键词： arc spray Fe-Cr-Al composite coating microstructure

Benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole-porphyrin-based near-infrared dyes

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smartMat 2021年第3期2卷 398-405页

作者： yi Liu shaofei Wu Tullimilli y.Gopalakrishna Jishan Wu Department of Chemistry National University of SingaporeSingaporeSingapore Joint school of National University of singapore and Tianjin University International Campus of Tianjin UniversityFuzhouBinhai New CityChina

Benzo[1,2-c;4,5-cʹ]bis[1,2,5]thiadiazole(BBT)has intrinsic diradical character and herein it is used to construct organic near-infrared(NIR)dyes together with the aromatic porphyrin *** BBT-porphyrin hybrid dyes 1-3 with different linkage modes are synthesized by Pd-catalyzed sonogashira crosscoupling between meso-ethynylene porphyrin units and monobromo-/dibromo-BBT,or through unexpected homocoupling between the BBT *** all possess small open-shell diradical character and display intense NIR absorption in the range of 800-1000 *** also exhibit amphoteric redox ***-based diradicaloids are thus good candidates for organic NIR dyes.

关键词： benzo[1,2-c 4,5-c']bisthiadiazole diradical character near-infrared dye porphyrin

PERFoRMANCE oF sTEEL MICRo FIBER REINFoRCED MoRTAR MIXTUREs CoNTAINING PLAIN,BINARy AND TERNARy CEMENTITIoUs sysTEMs

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Journal of Green Building 2016年第4期11卷 109-130页

作者： Ali Mardani-Aghabaglou Cihat yüksel Hojjat Hosseinnezhad Kambiz Ramyar Department of Civil Engineering Eng.FacultyUludağUniversityNilüfer-BursaTurkey epartment of Civil Engineering Eng.FacultyEge UniversityBornova-İzmirTurkey

steel micro fibers provide strengthening,toughening and durability improve-ment mechanisms in cementitious ***,there is not much data in the literature regarding how the extent of their effectiveness changes depend-ing on the type of matrix being *** clarifying this point,the influ-ence of a constant volumetric ratio(1%)of 6 mm long steel micro fibers on the performance of 5 mortar mixtures was investigated and were prepared using plain,binary and ternary cementitious systems.A total of 10 mixtures were *** mineral admixtures used in the study include silica fume(sF),metakaolin(MK)and a Class C fly ash(FA).While the replacement levels of sF and MK were 10%by weight of the total mass of the binder,this ratio was chosen as 30%for *** addition to the behavior of the mixtures under compressive,flexural and impact loads,abrasion,water absorption,chloride ion penetration,freez-ing-thawing resistance and drying shrinkage characteristics of the mixtures were *** results indicate that generally the refinement in the pore struc-ture of the matrix provided by mineral admixtures and the increase in resistance against growth and coalescence of micro-cracks provided by fibers produce a syn-ergistic effect and improve the investigated performances of the mixtures.

关键词： steel micro fiber mineral admixtures mechanical and transport properties durability performance

EFFECT oF sILICoN oN THE MICRosTRUCTURE AND MECHANICAL PRoPERTIEs oF yTTRIUM MoDIFIED Ni_3Al BAsE ALLoy IC6

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Acta Metallurgica sinica(English Letters) 1998年第6期11卷 437-441页

作者： C.B.Xiao y.F.Han X.A.Zhang Beijing Inst of Aeronautical Materials Beijing China

The effect of different amounts of silicon on the microstructure of the yttrium modified Ni3Al base alloy IC6 was studied with transmission electron microscope (TEM). The chemical compositions of phases formed due to the presence of silicon and yttrium were analyzed with energy dispersive spectrum(EDs) technique of electron probe microstructural analysis (EPMA). The results showed that a bulk shape phase rich in Mo and si was formed in the alloys with addition of 0.10-0.20wt%si and 0.12wt%y, and that a needle like phase named y-NiMo was precipitated in the interdendritic area in the alloy with addition of 0.30wt%si and 0.12wt%y besides the formation of the bulk shape phase mentioned above. The stress rupture properties under 1100℃/80MPa and the thermal fatigue properties at 1100℃ were improved by adding 0. 12wt%y but decreased by adding 0.10-0.30wt%si and 0.12wt%y. The addition of 0. 10-0.20wt%si and 0.12wt%y has no obvious influence on the tensile properties of alloy IC6 at room temperature (R. T.), 760, and 900℃, respectively.

关键词： silicon yttrium Ni_3Al microstructure mechanical property