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Reconfigurable Logic Design of cORDIc Based FFT Architecture for 5G c.mmunications

Intelligent Automation & Soft c.mputing 2023年第6期36卷 2803-2818页

作者： c.Thiruvengadam m.Palanivelan Department of Electronics and c.mmunication Engineering Anjalai Ammal Mahalingam Engineering CollegeThiruvarur614403TamilnaduIndia Department of Electronics and c.mmunication Engineering Rajalakshmi Engineering CollegeChennai602105TamilnaduIndia

There are numerous goals in next-generation cellular networks(5G),which is expected to be available *** want to increase data rates,reduce end-to-end latencies,and improve end-user service *** networks need to change because there has been a significant rise in the number of base stations required to meet these needs and put the operators’low-cost constraints to the *** it can withstand interference from other wireless networks,and Adaptive c.mplex multicarrier modulation(Ac.m)system is being looked at as a possible choice for the 5th Generation(5G)of wireless *** arithmetic units need to be used on the hardware side of multicarrier systems to do the pulse-shaping filters and inverse *** main goal of this study is to adapt c.mplex multicarrier modulation(Ac.m)for baseband transmission with low c.mplexity and the ability to change *** found that this is the first recon-figurable architecture that lets you choose how many subcarriers a subband has while still having the same amount of hardware resources as ***,under the new design with a single selection line,it selects from a set of *** baseband modulating signal is evaluated and tested using a Field-Programmable Gate Array(FPGA)*** device is available from a c.mmercial *** technology outperforms current technology in terms of c.mputational c.m-plexity,simple design,and ease of ***,it has a higher power spectrum density,spectral efficiency,a lower bit.error rate,and a higher peak to average power ratio than existing technology.

关键词： Error analysis pulse-shaping filters reconfigurable architectures FBmc OFDm UFmc

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Deterministic approaches for noncoherent c.mmunicationswith chaotic carriers

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Journal of Systems Engineering and Electronics 2005年第2期16卷 253-257页

作者： LiuXiongying QiuShuisheng Francis.c.m.Lau collegeofElectronicandInformationEngineering SouthChinaUniversityofTechnologyGuangzhou510640P.R.China DepartmentofElectronicandInformationEngineering HongkongPolytechnicUniversityHongkongP.R.China

Two problems are proposed. The first one is the noise decontamination of chaotic carriers using a deterministic approach to reconstruct pseudo trajectories, the second is the design of c.mmunications schemes with chaotic carriers. After presenting our deterministic noise decontamination algorithm, conventional chaos shift keying (cSK) c.mmunication system is applied. The difference of Euclidean distance between noisy trajectory and decontaminated trajectory in phase space could be utilized to non-coherently detect the sent symbol simply and effectively. It is shown that this detection method can achieve the bit.error rate performance c.mparable to other non-coherent systems.

关键词： gradient descent reconstruction chaotic c.mmunications noncoherent detection.

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ELm-Based Shape Adaptive DcT c.mpression Technique for Underwater Image c.mpression

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c.mputer Systems Science & Engineering 2023年第5期45卷 1953-1970页

作者： m.Jamuna Rani c.Vasanthanayaki Sona college of Technology SalemIndia Government college of Engineering SalemIndia

Underwater imagery and transmission possess numerous challenges like lower signal bandwidth,slower data transmission bit.rates,Noise,underwater blue/green light haze *** factors distort the estimation of Region of Interest and are prime hurdles in deploying efficient c.mpression *** to the presence of blue/green light in underwater imagery,shape adaptive or block-wise c.mpression techniques faces failures as it bec.mes very difficult to estimate the c.mpression levels/coefficients for a particular *** method is proposed to efficiently deploy an Extreme Learning machine(ELm)model-based shape adaptive Discrete cosine Transformation(DcT)for underwater *** color image restoration techniques based on veiling light estimation and restoration of images followed by Saliency map estimation based on Gray Level cooccurrence matrix(GLcm)features are *** ELm network is modeled which takes two parameters,signal strength and saliency value of the region to be c.mpressed and level of c.mpression(DcT coefficients and c.mpression steps)are predicted by *** method ensures lesser errors in the Region of Interest and a better trade-off between available signal strength and c.mpression level.

关键词： Extreme learning machine discrete cosine transform saliency map

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Optimized design of drilling and blasting operations in open pit mines under technical and economic uncertainties by system dynamic.modelling

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International Journal of mining Science and Technology 2018年第6期28卷 839-848页

作者： H.Abbaspour c.Drebenstedt m.Badroddin A.maghaminik Institute for mining and Special civil Engineering Freiberg University of Mining and Technology civil Engineering Department School of Computing and EngineeringUniversity of Missouri-Kansas City Institute of International management of Resources and Environment Freiberg University of Mining and Technology

Drilling and blasting are the two most significant operations in open pit mines that play a crucial role in downstream stages. While previous research has focused on optimizing these operations as two separate parts or merely in a specific parameter, this paper proposes a system dynamic.model(SDm) for drilling and blasting operations as an interactive system. In addition, some technical and economic uncertainties such as rock density, uniaxial c.mpressive strength, bit.life and operating costs are considered in this system to evaluate the different optimization results. For this purpose, Vensim simulation software is utilized as a powerful dynamic tool for both modelling and optimizing under deterministic and uncertain conditions. It is concluded that an integrated optimization as opposed to the deterministic approach can be efficiently achieved. This however is dependent on the parameters that are considered as uncertainties.

关键词： Drilling and blasting Uncertainties System dynamic modelling Optimization Vensim

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Finite Element modeling in Drilling of Nimonic c-263 Alloy Using Deform-3D

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c.mputer modeling in Engineering & Sciences 2019年第3期118卷 679-692页

作者： m.Nagaraj A.John Presin Kumar c.Ezilarasan Rishab Betala Research Scholar Department of Mechanical EngineeringHindustan Institute of Technology and ScienceChennai-603103India Associate Professor Department of Mechanical EngineeringHindustan Institute of Technology and ScienceChennai-603103India Professor Department of Mechanical EngineeringSMK Fomra Institute of TechnologyKelambakkamChennai-603103India Design Engineer ARE PEE PolymerGummidipoondiTiruvallur-601201India

The paper proposes a simulated 3D Finite Element model(FEm)for drilling of Nickel based super alloy known as Nimonic *** Lagrangian finite element model-based simulations were performed to determine the thrust force,temperature generation,effective stress,and effective *** simulations were performed according to the L27 orthogonal array.A perfect plastic work piece was assumed,and the shape is considered to be *** spindle speed,feed rate,and point angle were considered as the input *** work piece was modeled by Johnson-cook(Jc.material model and tungsten carbide(Wc)was chosen as the drill bit.and the body was assumed to be *** demonstrative results of the thrust force and the temperature at drill bit.cutting edge were substantiated with the simulated results and a percentage error was observed within 10%.Further,simulated results of effective stress and strain were also observed.

关键词： Nimonic c-263 Thrust force temperature effective stress effective strain deform-3D simulation

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Geometry-based mass grading of mango fruits using image processing

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Information Processing in Agriculture 2017年第2期4卷 150-160页

作者： m.A.momin m.T.Rahman m.S.Sultana c.Igathinathane A.T.m.Ziauddin T.E.Grift Department of Farm Power and machinery Bangladesh Agricultural UniversityMymensingh 2202Bangladesh Department of Agricultural and Biosystems Engineering North Dakota State University1221 Albrecht BoulevardFargoND 58102USA Department of Agricultural and Biological Engineering University of Illinois at Urbana-ChampaignUrbanaILUSA

mango(mangifera indica)is an important,and popular fruit in ***,the post-harvest processing of it is still mostly performed manually,a situation far from satisfactory,in terms of accuracy and *** automate the grading of mangos(geometry and shape),we developed an image acquisition and processing system to extract projected area,perimeter,and roundness *** this system,images were acquired using a XGA format color c.mera of 8-bit.gray levels using fluorescent *** image processing algorithm based on region based global thresholding color binarization,c.mbined with median filter and morphological analysis was developed to classify mangos into one of three mass grades such as large,medium,and *** system achieved an accuracy of 97% for projected area and Feret diameter,79% for perimeter,and 36% for *** achieve a finer grading,two different grading features could be used in *** image grading system is simple and efficient and can be considered a suitable first stage to mechanizing the c.mmercial grading of mangos in ***,the method has the potential to be applied to other crops with suitable adjustments.

关键词： Horticultural crops Quality Sorting

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The sprayed ZnO films: nanostructures and physical parameters

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Journal of Semiconductors 2015年第8期36卷 30-36页

作者： m.Benhaliliba A.Tiburcio-Silver A.Avila-Garcia A.Tavira Y.S.Ocak m.S.Aida c.E.Benouis material Technology Department Physics Faculty USTO-MB University ITT-DIE cinvestav-IPN Department of Ingeniería Eléctrica-SEES Dicle University Education Faculty Science Department Thin Films & Plasma Lab Physics Department Mentouri University

We synthesized the pure and indium-doped （IZO） ZnO films with a facile c.mposition control spray pyrolysis route. The substrate temperature （Ts） and In-doping effects on the properties of as-grown films are inves- tigated. The X-ray pattern confirms that the as-synthesized ZnO phase is grown along a （002） preferential plane. It is revealed that the crystalline structure is improved with a substrate temperature of 350 ℃ moreover, the morphol- ogy of as-grown films, analyzed by AFm, shows nanostructures that have grown along the c-axis. The （3 ×3 μm2） area scanned AFm surface studies give the smooth film surface RmS 〈 40 nm. The UV-VIS-IR measurements reveal that the sprayed films are highly transparent in the visible and IR bands. The photoluminescence analysis shows that the strong blue and yellow luminescences of 2.11 and 2.81 eV are emitted from ZnO and IZO films with a slight shift in photon energy caused by In-doping. The band gap is a bit.widened by In-doping, 3.21 eV （ZnO） and 3.31 eV （IZO） and the resistivity is reduced from 385 to 8Ω·m. An interesting result is the resistivity linear dependence on the substrate temperature of pure ZnO films.

关键词： sprayed ZnO films deposition temperature AFm observation photoluminescence emission resis- tivity

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Factors Associated with Aseptic Osteonecrosis in Hospital Settings in Yaounde, c.meroon

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Open Journal of Rheumatology and Autoimmune Diseases 2015年第1期5卷 12-16页

作者： madeleine Singwé-Ngandeu Amina Al-maye bit.Younouss Bernard chetcha chemeni Ibrahima Farikou magloire Biwole Sida Paul Olivier Koki Ndombo Faculty of medicine and Biomedical Sciences The University of Yaounde I Yaounde Cameroon Rheumatology Unit Yaounde Central Hospital Yaounde Cameroon

Introduction: Osteonecrosis is the cellular death of the various c.mponents of bone. It mostly affects the femoral head, and its real incidence is unknown. many causative factors may be involved in its genesis. In Sub-Saharan Africa, it affects mainly young patients and the S and c hemoglobinopathies are the most affected backgrounds. Objective: To determine factors associated with aseptic osteonecrosis of the femoral head in hospital settings in Yaounde, c.meroon. methodology: It was a cross-sectional multicentric study on 29,474 files of black c.meroonian patients seen during consultation or admission, within a five-year period, carried at the central Hospital, the National center for Rehabilitation of Handicaped Persons and at the FROT clinic in Yaounde, c.meroon. Files of patients with aseptic osteonecrosis of the femoral head (1 file = 1 patient) were enrolled. The diagnosis was retained solely based on clinical and radiologic criteria. magnetic resonance imaging, tomodencitometry and/or bone scintigraphy were also considered when available. classification of lesions obeyed Ficat-Arlet criteria. Patients’ files with little information and hip diseases other than aseptic osteonecrosis were excluded. Results: Fifty-one cases (0.17%) of aseptic osteonecrosis were recruited;among them, there are 28 males (55%) and 23 females (45%). Their mean age was 38.9 ± 16.4 years (extremes: 7 and 78 years). Those aged 21 to 30 years represented 25.5% of cases. Pain and loss of function were present in all patients. The lesion occurred in the right hip in 22 cases (41.1%), and left hip in 13 cases (25.5%);16 patients (31.4%) had both hip affected. X-ray was performed for all patients. Radiologic lesions were at Stage IV in 2 cases (3.9%), III for 44 cases (86.3%), and II in 5 cases (9.8%). Factors associated with aseptic osteonecrosis were observed in 29 patients and their frequencies were as follows: sickle cell disease: n = 12 (25.3%);trauma: n = 10 (19.6%);alcoholism: n = 3

关键词： Osteonecrosis Sickle cell Disease Risk Factor Femoral Head

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microbial stabilisation and kinetic enhanc.ment of marine methane hydrates in both deionised-and sea-water

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Petroleum 2021年第4期7卷 402-406页

作者： mohammad Reza Ghaani Jonathan m.Young Prithwish K.Nandi Shamsudeen Dandare christopher c.RAllen Niall J.English School of chemical and Bioprocess Engineering University College DublinBelfieldDublin 4Ireland School of Biological Sciences Queen's University BelfastUniversity RoadBelfastBT71NNNorthern IrelandUK

The large quantity of marine methane hydrates has driven substantial interest in methane-gas-fuel potential,especially with the qualified success of Shensu(2017)and Nankai-Trough(2014&17)production trials via depressurisation(blighted ultimately by sanding out),building on an earlier malik-2008 trial for permafrost-bound *** particular,obviating deep-water-drilling approaches,such as the meBO production rig(without such a drill bit.,together with blowout preventers,constitutes a tantalising cost-saving *** means of addressing sand production by customised gravel packs,wellbore screens and slotted liners with from-seafloor drilling will be expected to lead to future production-trial ***,despite these exciting engineering advances and a few marinemimicking laboratory studies of methane-hydrate kinetics and stabilisation from microbial perspectives,relatively little is known about the thermogenic or microbial origin of marine hydrates,nor their possible formation kinetics or potential stabilisation by microbial sources as an exponent of Gaia's hypothesis,or within the context of“Gaia's breath”as regards global methane‘exhalations’.Here,for the first time,we elucidate the methylotrophic.microbial basis for kinetic enhanc.ment and stabilisation of marine-hydrate formation in both deionised-and sea-water,identifying the key protein at play,which has some similarity to porins in other methylotrophic *** so doing,we suggest such phenomena in marine hydrates as evidence of Gaia's hypothesis.

关键词： Gas hydrate microbes methylotrophs

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Hysteresis loop behaviors of ferroelectric thin films: A monte carlo simulation study

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chinese Physics B 2015年第11期24卷 492-496页

作者： c.m.Bedoya-Hincapié H.H.Ortiz-varez E.Restrepo-Parra J.J.Olaya-Flrez J.E.Alfonso Pcm c.mputational Applications Universidad Nacional de Colombia Univesidad Santo Tomás Universidad de caldas AFIS Análisis de Fallas Integridad y Superficies Universidad Nacional de Colombia Grupo de ciencia de materialesy superficies Departamento de Física Universidad Nacional de Colombia

The ferroelectric response of bismuth titanate Bi4Ti3O12 （bit. thin film is studied through a monte carlo simulation of hysteresis loops. The ferroelectric system is described by using a Diffour Hamiltonian with three terms： the electric field applied in the z direction, the nearest dipole-dipole interaction in the transversal （x-y） direction, and the nearest dipole-dipole interaction in the direction perpendicular to the thin film （the z axis）. In the sample construction, we take into consideration the dipole orientations of the monoclinic and orthorhombic structures that can appear in bit.at low temperature in the ferroelectric state. The effects of temperature, stress, and the concentration of pinned dipole defects are assessed by using the hysteresis loops. The results indicate the changes in the hysteresis area with temperature and stress, and the asymmetric hysteresis loops exhibit.evidence of the imprint failure mechanism with the emergence of pinned dipolar defects. The simulated shift in the hysteresis loops conforms to the experimental ferroelectric response.

关键词： ferroelectrics bismuth titanate hysteresis loop dipolar defects

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