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Design of Floating Mass Type Piezoelectric Actuator for Implantable Middle Ear Hearing Devices

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 221-226页

作者： LIU Houguang TA Na MING Xiaofeng rao Zhushi State Key Laboratory of Mechanical System and vibrations Shanghai Jiao Tong University Shanghai 200240 China

To overcome some of the problems inherent in conventional heating aids such as low gain at high fi＇equencies due to acoustic feedback, discomfort in occlusion of the extemal ear canal and so on, implantable middle ear hearing devices （IMEHDs） have been developed over the past two decades. For such kinds of IMEHDs, this paper presents the design of a floating mass piezoelectric actuator using a PMN-30%PT stack as a new type of vibrator. The proposed piezoelectric actuator consists of only three components of a piezoelectric stack, a metal case and a clamp. For the purpose of aiding the design of this actuator, a coupling biomechanics model of human middle ear and the piezoelectric actuator was constructed. This model was built based on a complete set of computerized tomography section images of a healthy volunteer＇s left ear by reverse engineering technology. The validity of this model was confirmed by comparing the motion of the tympanic membrane and stapes footplate obtained by this model with published experimental measurements on human temporal bones. It is shown that the designed actuator can be implanted on the incus long process by a simple surgical operation, and the stapes footplate displacement by its excitation at 10.5 v root-mean-square（RMS） voltage was equivalent to that from acoustic stimulation at 100 dB sound pressure level（SPL）, which is adequate stimulation to the ossicular chain. The corresponding power consumption is 0.04 mW per volt of excitation at 1 kHz, which is low enough for the transducer to be used in an implantable middle ear device.

关键词： piezoelectric actuator implantable middle ear hearing device floating mass fmite element model

Petrogenesis of carbonatitic lamproitic dykes from Sidhi gneissic complex,Central India

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Geoscience Frontiers 2018年第2期9卷 531-547页

作者： M.Satyanarayanan D.v.Subba rao M.L.Renjith S.P.Singh E.v.S.S.K.Babu M.M.Korakoppa CSIR-National Geophysical Research Institute Hyderabad 500007India Geological Survey of India Hyderabad 500068India Department of Geology Bundelkhand UniversityJhansi 284128India NCEGR Geological Survey of IndiaBengaluru 560070India

Petrographic, mineral chemical and whole-rock geochemical characteristics of two newly discovered lamproitic dykes(Dyke 1 and Dyke 2) from the Sidhi Gneissic Complex(SGC), Central India are presented here. Both these dykes have almost similar sequence of mineral-textural patterns indicative of:(1) an early cumulate forming event in a deeper magma chamber where megacrystic/large size phenocrysts of phlogopites have crystallized along with subordinate amount of olivine and clinopyroxene;(2) crystallization at shallow crustal levels promoted fine-grained phlogopite, K-feldspar, calcite and Fe-Ti oxides in the groundmass;(3) dyke emplacement related quench texture(plumose K-feldspar, acicular phlogopites) and finally(4) post emplacement autometasomatism by hydrothermal fluids which percolated as micro-veins and altered the mafic phases. Phlogopite phenocrysts often display resorption textures together with growth zoning indicating that during their crystallization equilibrium at the crystal-melt interface fluctuated multiple times probably due to incremental addition or chaotic dynamic self mixing of the lamproitic magma. Carbonate aggregates as late stage melt segregation are common in both these dykes, however their micro-xenolithic forms suggest that assimilation with a plutonic carbonatite body also played a key role in enhancing the carbonatitic nature of these dykes. Geochemically both dykes are ultrapotassic(K_2 O/Na_2 O: 3.0-9.4) with low CaO, Al_2 O_3 and Na_2 O content and high SiO_2(53.3-55.6 wt.%)and K_2 O/Al_2 O_3 ratio(0.51-0.89) characterizing them as high-silica lamproites. Inspite of these similarities, many other features indicate that both these dykes have evolved independently from two distinct magmas. In dyke 1, phlogopite composition has evolved towards the minette trend(Al-enrichment) from a differentiated parental magma having low MgO, Ni and Cr content; whereas in dyke 2, phlogopite composition shows an evolutionary affinity towards the lamproit

关键词： Lamproite Phlogopite Carbonate aggregates Metasomatized mantle Sidhi Gneissic Complex Central India

A Bio-Inspired Method for Breast Histopathology Image Classification Using Transfer Learning

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Journal of Artificial Intelligence and Technology 2024年第2期4卷 89-101页

作者： R.K.chandana Mani J.Kamalakannan Y.Pandu Rangaiah Sesham Anand vellore Institute of Technology VelloreTNIndia G.Pullaiah College of Engineering and Technology KurnoolAndhra PradeshIndia Maturi venkata Subba rao Engineering College HyderabadIndia

Breast cancer is one of the deadly cancer among the female population and still a developing area of research in the field of medical *** fatality rate is more in patients who are not early diagnosed and are given delayed ***,researchers are keeping their lot of efforts in developing breast cancer detection systems that could provide accurate diagnosis in the initial stages which are relied on medical *** learning is offering key solutions to overcome many image classification *** deep learning techniques have extended their root to many medical fields even it suffers from the problem of lack of sufficient *** neural networks are more preferred for medical image classification *** this paper,we propose a transfer learning method that overcomes the issue of insufficient *** use a familiar pre-trained network vGG-16(visual Geometric Group)+with logistic regression as a binary *** hyper-parameters of every CNN have a closer impact on the performance of the entire deep learning model,our method focuses on optimizing hyper-parameters using particle swarm optimization which is a bio-inspired *** proposed model performs the classification of breast histopathology images into benign and malignant images and produce better *** use BreakHis Dataset to test our method and achieve an accuracy of around 96.9%.The experimental results show that this study has improved performance metrics when compared to other transfer learning methods.

关键词： bio-inspired algorithms breast cancer convolutional neural networks data augmentation swarm optimization

H∞ Loop-shaping Design of Flexible Systems

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H∞ Loop-shaping Design of Flexible Systems

Experimental Studies on the Self-Shielding Effect in Fissile Fuel Breeding Measurement in Thorium Oxide Pellets Irradiated with 14 Mev Neutrons

第25届中国控制与决策会议

作者： rao Hongliang Wuhan University of Science and Technology

ISBN: (纸本)9781467355339

The control design of the flexible system and the specific flexible characteristics are related, from a control angle of the flexible system is divided into a shaft drive mechanism, the truss structure and the sheet-type structure into three categories. Obvious characteristics of flexible sheet-type structure flexible system design examples show that the H∞ loop shaping method can effectively solve the difficulties the sheet type structure flexible system design to ensure the stability of the system, that is a sharp decline in the amplitude-frequency characteristics band within. General H∞ control theory, H∞ norm is performance indicators. But the actual design of the H∞ loop shaping method H∞ norm is represented stability margin, only the design specifications, and its performance is determined by the weighting function of forming the loop shaping design H∞ controller used to meet the robust stability guarantee stability margin. The article also pointed out that the H∞ loop shaping method is not given perturbation range of design issues, so the concept of robust design is also different from the conventional H control design.

关键词： flexible systems H∞ loop-shaping H∞ norm robustness performance

来源： cnki会议评论

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Plasma Science and Technology 2013年第2期15卷 166-170页

作者： Mitul ABHANGI Nupur JAIN Rajnikant MAKWANA Sudhirsinh vALA Shrichand JAKHAR T. K. BASU C. v. S. rao Fusion Neutronics Laboratory Institute for Plasma ResearchBhat Gandhinagar-382428Gujarat India School of Nuclear Energy Pandit Deendayal Petroleum UniversityGandhinagarGujarat 382007 India

The 14 Mev neutrons produced in the D-T fusion reactions have the potential of breeding Uranium-233 fissile fuel from fertile material Thorium-232. In order to estimate the amount of U-233 produced, experiments are carried out by irradiating thorium dioxide pellets with neutrons produced from a 14 Mev neutron generator. The objective of the present work is to measure the reaction rates of 232Th ＋ in --＊ 233Th --＊ 2a^Pa --＊ 2a3U in different pellet thicknesses to study the self-shielding effects and adopt a procedure for correction. An appropriate assembly consisting of high-density polyethylene is designed and fabricated to slow down the high-energy neutrons, in which Thorium pellets are irradiated. The amount of fissile fuel （~3~U） produced is estimated by measuring the 312 kev gammas emitted by Protactinium-233 （half-life of 27 days）. A calibrated High Purity Germanium （HPGe） detector is used to measure the gamma ray spectrum. The amount of 233U produced by Th232 （n, ~） is calculated using MCNP code. The self-shielding effect is evaluated by calculating the reaction rates for different foil thickness. MCNP calculation results are compared with the experimental values and appropriate correction factors are estimated for self-shielding of neutrons and absorption of gamma rays.

关键词： 233U breeding fissile fuel MCNP 14 Mev neutron source

New Archaeological sites in the Gulf of Cambay,India

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Episodes 2003年第1期26卷 16-18页

作者： Kathiroli, S. Badrinarayanan, S. rao, D.v. Sasisekaran, B. Sivakolundu, K.M. National Institute of Ocean Technol. Chennai India

India, with a coastline of over 7,500 km, is known to have engaged in maritime trade from the second half of the first millennium BC. Geophysical surveys conducted off the coast of Bombay, Laccadives, Tranquebar, Kutch, Cambay, Kaveripattinam and visakapatnam have recorded shipwrecks, submerged cities, ports and channels. It is highly probable that the shelf off the Andhra, Kerala, Gujarat and Tamil Nadu coasts, if properly surveyed, will yield not only vestiges of prehistoric man and his tools but also submerged river channels and ports. A preliminary survey of the Gulf of Cambay with side-scan sonar soundings and a sub-bottom profiler revealed unnatural features. Further exploration through dredging brought to light artefacts that bore testimony to human activity.

关键词：考古遗址坎贝湾印度海岸线海上贸易人类活动

Friction assisted solid state lap seam welding and additive manufacturing method

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Defence Technology（防务技术） 2016年第1期12卷 16-24页

作者： Prasad rao KALvALA Javed AKRAM Mano MISRA Dept. of Metallurgical Engineering University of Utah

This paper describes results of seam welding of relatively high temperature melting materials, AISI 304, C-Mn steels, Ni-based alloys, CP Cu, CP Ni, Ti6Al4v and relatively low temperature melting material, AA6061. It describes the seam welding of multi-layered similar and dissimilar metallic sheets. The method described and involved advancing a rotating non-consumable rod(CP Mo or AISI 304) toward the upper sheet of a metallic stack clamped under pressure. As soon as the distal end of the rod touched the top portion of the upper metallic sheet, an axial force was applied. After an initial dwell time, the metallic stack moved horizontally relative to the stationery non-consumable rod by a desired length, thereby forming a metallurgical bond between the metallic sheets. Multi-track and multi-metal seam welds of high temperature metallic sheets, AISI 304, C-Mn steel,Nickel-based alloys, Cp Cu, Ti6Al4v and low temperature metallic sheets, AA6061 were obtained. Optical and scanning electron microscopy examination and 180 degree U-bend test indicated that defect free seam welds could be obtained with this method. Tensile- shear testing showed that the seam welds of AISI 304, C-Mn steel, Nickel-based alloy were stronger than the starting base metal counterparts while AA6061 was weaker due to softening. The metallurgical bonding at the interface between the metallic sheets was attributed to localized stick and slip at the interface, dynamic recrystallization and diffusion. The method developed can be used as a means of welding, cladding and additive manufacturing.

关键词： Lap seam welding Friction assisted welding Solid-state welding Cladding Additive manufacturing

Increased oxidative stress and altered antioxidants status in patients with chronic allergic rhinitis

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Advances in Bioscience and Biotechnology 2012年第7期3卷 951-956页

作者： Shiefa Sequeira Ashalatha v. rao Anjali rao Department of Biochemistry K. S. Hegde Medical Accademy Deralakatte Mangalore India Department of Biochemistry Kasturba Medical College Manipal India Department of Biochemistry SRL Diagnostics Dubai UAE

Background: Allergic rhinitis is an inflammatory disorder of the upper airways. Although several oxidants and antioxidants are likely to be involved, alterations in only limited parameters have been studied. Objective: In this study an attempt has been made to study the oxidant-antioxidant imbalance by investigating changes in a wide range of oxidants and antioxidants in the blood. Methods: Blood samples were obtained from 39 chronic allergic rhinitis patients (males 24, females 15), aged 20-70 (mean age 36.33 ± 2.03) years and 53 individuals (36 males, 17 females);aged 24 to 64 (mean age 45.42 ± 1.36) years. Duration of allergic rhinitis was 1.77 ± 0.237 years. In the study group, nasal symptoms were scored and the results were recorded. The patients were classified as having perennial Allergic rhinitis (PAR) if they had had at least 2 rhinitis symptoms (sneezing, rhinorrhea, nasal obstruction, itching) for at least 6 months a year in the previous 2 years and if they had a positive skin prick test response to at least 1 clinically significant perennial allergen (e.g., house dust mites, molds, cockroach, cockroach excrement grass and tree pollen, cat and dog epithelia and molds, or animal dander). They had no other allergic diseases except persistent allergic rhinitis diagnosed by the physical and history examination. Erythrocyte lipid peroxidation, erythrocyte antioxidants viz., glutathione, glutathione reductase, superoxide dismutase, catalase and plasma antioxidants viz., ceruloplasmin, glutathione-S-transferase, vitamin C, total antioxidant activity were estimated in the above two groups. Results: Erythrocyte lipid peroxidation (0 hour, p vitamin C (p vity (p < 0.001) were significantly lower in chronic allergic rhinitis patients when compared to controls. Plasma Glutathione S transferase and erythrocyte catalase, glu

关键词： Oxidative Stress Antioxidant Status Chronic Allergic Rhinitis

Relationships between the Global General Circulation and the Indian Summer Monsoon

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Advances in Atmospheric Sciences 1991年第2期8卷 137-148页

作者： M. Sankar-rao v. N. Lvkossov E. M. volodin A. E. Nikitin A. I. Degtiarev Kusuma G. rao Department of Aerospace Engineering and Centre for Atmospheric Sciences Indian Institute of Science Bangalore 560012 INDIADepartment of Numerical Mathematics USSR Academy of Sciences Moscow USSRDepartment of Numerical Mathematics USSR Academy of Sciences Moscow USSRHydrometeorological Centre Moscow USSRHydrometeorological Centre Moscow USSRCentre for Atmospheric Sciences Indian Institute of Science Bangalore 560012 INDIA

The relationships between the global general circulation and the Indian monsoon during active and break phases are investigated with the help of FGGE IIIb *** was found that the ultralong wave component positive and negative height anomalies over Tibet are associated with active and break monsoon phases respectively. This ultralong wave component has significant effect even upto 22°N over the Indian region which is the monsoon trough region. During a monsoon break, the general circulation was found to be more turbulent in the sense that more waves become *** was observed that during a break, blocking prevails over the Siberian region and cold air advection takes place toward Indian region from Siberian region depressing the temperatures over the Indian region by about 1℃. During the break, the Indian region gets connected with higher latitudes by the south winds blowing from polar Soviet regions to the Indian region. From active to break phase the zonal component weakens by about 25% from Indian ocean area right upto Alaskan region, along the east coast of Asia.

关键词： over In Mean