Analysis and determination of cogging torque and unbalanced magnetic forces in permanent magnet spindle motors for hard disk drives

... the electromagnetic forces are extremely stringent Electromagnetic forces such as the cogging torque and unbalanced magnetic pull (UMP) generated in the permanent magnet spindles are of great concerns ... Modeling and Analysis of PM Brushless DC Motors 2.1 Electromagnetic Field in PM Brushless DC Motors In order to study the electromagnetic forces and torques in permanent magnet spindle motors, ... magnet motors used in hard disk drives 2) To build a model for predicting the electromagnetic forces developed in PM motors with sufficient accuracy required for design and analysis of PM spindle...

Robust design of miniaturised spindle motors for hard disk drive

... ROBUST DESIGN OF MINIATURISED SPINDLE MOTORS FOR HARD DISK DRIVE GAO XIAN KE (M.Eng, B.Eng) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF ELECTRICAL AND ... application of robust design in hard disk drive industry As the objective of the research is to formulate effective robust design approaches systematically for the design and optimization of miniaturized ... Introduction of this study is to formulate the effective robust design approaches systematically and generally for design and optimization of electromechanical systems in hard disk drive The design...

Analysis, design and control of permanent magnet synchronous motors for wide speed operation

... Torque performance of SVM based DTC and Current Control for a wide speed operation 169 6.26 Power performance of SVM based DTC and Current Control for a wide speed operation ... Control of IPMSM in Wide Speed Operation 24 Outline of the Thesis 25 Analysis of Interior Permanent Magnet Synchronous Motors for Wide- Speed Operation ... presents aspects of analysis, design and control of permanent magnet synchronous motors (PMSMs) for wide- speed operations An analytical method has been developed based on d- and q- axis equivalent...

Báo cáo hóa học: " Cross-Layer Quality-of-Service Analysis and Call Admission Control in the Uplink of CDMA Cellular Networks" potx

... capacity and leads to the determination of admission region in the uplink of CDMA systems Our analytical work can be further combined with the call level analysis of QoS performances to provide a joint ... cross-layer CAC in CDMA networks Our contribution is that the analytical formulation in this paper leads to the determination of the crosslayer admission region (AR) in the uplink of a CDMA system ... “Performance analysis of multiclass services in the uplink of wideband CDMA, ” in Proceedings of the 8th International Conference on Communication Systems (ICCS ’02), vol 2, pp 692– 696, Singapore,...

Design optimization of permanent magnet synchronous motors using response surface analysis and genetic algorithm

... The development of Permanent Magnet Machines 1.1.2 Features of permanent magnet motors Permanent magnet synchronous motors iii 1.2.1 Structures and operating principles ... with the analysis and design of buried type Interior Permanent Magnet Synchronous Motors (IPMSM) The objective is to develop a design optimization procedure for this type of motors that is more ... List of Figures 1.1 Magnetic characteristics of the main class of permanent magnets [2] 1.2 Evolution of the magnetic material during the 20th century [2] 1.3 Partial demagnetization of a permanent...

Báo cáo lâm nghiệp: "Whole tree hydraulic conductance and water loss regulation in Quercus during drought: evidence for stomatal control of embolism?" doc

... throughout the growing season Hydraulic conductance and water loss In figure 2, we represented for one representative drought tree and one control tree the seasonal patterns of the daily water potential/sap ... objective of this paper is to test the hypothesis that sap flow and water losses are regulated during drought according to changes in whole tree hydraulic conductance in order to avoid development of ... density and thus the degree of stomatal regulation in Quercus petraea can therefore be inferred from the water transport capacity of the whole tree (gL) and the xylem vulnerability to embolism induced...

Exploration on in situ diagnosis methods for the evaluation of mechanical and magnetic performance of hard disk drives

... Chapter Introduction The modern information technology consists of three parts: information acquiring, information processing, information transferring and information storage In fact, information ... Exploration of In- Situ Diagnosis Methods for the Evaluation of Mechanical and Magnetic Performance of Hard Disk Drives ZHU JIN （B.Eng (hons) HUST, P.R.China） A THESIS SUBMITTED FOR THE DEGREE ... surface of the disk As the introduction of mini and micro computer technology, the disk size used in disk drives was shrunk from 24 inch diameter in 1950s, to ~ 12 inch in 1960s and 1970s, and 5.25...

Đề tài " Determination of the algebraic relations among special Γ-values in positive characteristic " pdf

... bj ¯ ¯ The ring k[t, σ] contains both the noncommutative ring k[σ] and the commu¯ as subrings The ring Fq [t] is contained in the center of the ring tative ring k[t] ¯ ¯ k[t, σ] The ring k[t, ... ((1/T )) = the | · |∞ -completion of k an algebraic closure of k∞ the | · |∞ -completion of k∞ the algebraic closure of k in C∞ ¯ a ﬁxed choice in k of a (q − 1)st root of −T the subring of the power ... Annals of Mathematics, 160 (2004), 237–313 Determination of the algebraic relations among special Γ-values in positive characteristic By Greg W Anderson, W Dale Brownawell∗ , and Matthew A Papanikolas...

Determination of Non-Steroidal Anti-Inflammatory Drugs (Nsaids) in Surface Water at Ho Chi Minh City

... at a low concentration and at a few sampling locations Table Concentration of the analyzed pharmaceutical compounds in surface water samples collected at Hồ Chí Minh City Sampling site River/Canal ... locations Particularly, ibuprofen concentration at Lê Văn Sỹ bridge is significantly higher than at other locations Regarding ketoprofen and diclofenac sodium, they only exist in surface water at ... 0.25 to 1.0 meter from the surface of water and stored in 2.5-liter amber glass bottles at 4oC until sample treatment [3] Fifteen surface water samples at Hồ Chí Minh City were collected on 23...

Báo cáo khoa học: Impact of cyclic hypoxia on HIF-1a regulation in endothelial cells – new insights for anti-tumor treatments doc

... effects on HIF-1a during cyclic hypoxia; caution is therefore required in the use of NOS inhibitors as single anti-tumor treatments More generally, by providing new insights into the regulation of HIF-1a ... to cyclic hypoxia despite degradation during reoxygenation We examined the impact of three cycles of h hypoxia ⁄ 30 reoxygenation (versus 1, and h of continuous hypoxia) on the abundance of HIF-1a ... following three cycles of h hypoxia (Fig 4C) Addition of rotenone had no effect on the induction of HIF-1a after uninterrupted or h hypoxia, indicating that, under our experimental conditions,...

Tài liệu Báo cáo Y học: NMR-based determination of the binding epitope and conformational analysis of MUC-1 glycopeptides and peptides bound to the breast cancer-selective monoclonal antibody SM3 pptx

... attached to Thr3 enhances binding afﬁnity of glycopeptides to the antibody [18] Conventional pepscan analysis however, does not allow easy analysis of the contribution of the carbohydrate portion To ... TSAPDTRPAPGST and the antibody SM3 was determined by Dokurno et al [19] They report a signiﬁcant contribution of Arg4 to binding by analyzing the surface of the residues covered by the protein They also ... between ˚ the peptide and the non binding bottom of the Fab is 173 A2 which corresponds to about 36% of the interaction of the full peptide with the binding cavity of SM3 The sizes of the surfaces...

analysis and determination of the stress intensity factor of load-carrying cruciform fillet welded joints

... one of the models under analysis (model 5) at final crack propagation 6.1.3 Calculation of the Stress Intensity Factors When a propagating crack is considered, the stress intensity factors and ... Effect of Crack Increment on SIF, Toe Crack crack) on the stress intensity factor (KI) under a constant load The applied edge stress for the model was based on the development of the yield stress ... Description and Boundary Conditions of Load-Carrying Cruciform Welded Joint Figure (3) shows the results of mesh sizes density It was noticed that there are no effects on the stability of results and the...

Báo cáo sinh học: " Determination of suitable housekeeping genes for normalisation of quantitative real time PCR analysis of cells infected with human immunodeficiency virus and herpes viruses" pdf

... Reference gene selection for quantitative real- time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections Virol ... of cell types infected with a variety of strains of HIV-1, HSV-1, VZV and cytomegalovirus (CMV) compared to mock infected cells Results A range of cell lines and primary cells were infected with ... reliable housekeeping genes in cells infected with a variety of viruses [7,12], however to date no such study has been carried out in cells infected with human immunodeficiency virus (HIV) or the herpes...

Báo cáo hóa học: " Determination of suitable housekeeping genes for normalisation of quantitative real time PCR analysis of cells infected with human immunodeficiency virus and herpes viruses" pot

... Reference gene selection for quantitative real- time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections Virol ... of cell types infected with a variety of strains of HIV-1, HSV-1, VZV and cytomegalovirus (CMV) compared to mock infected cells Results A range of cell lines and primary cells were infected with ... shortlist of potential candidates To date the variability of housekeeping gene expression has been studied in cells infected with SARS corona virus, yellow fever virus, human herpes virus6 , camelpox virus, ...

Báo cáo hóa học: " Analysis of in vitro replicated human hepatitis C virus (HCV) for the determination of genotypes and quasispecies" docx

... cell culture on the fidelity of replication of HCV We tested the impact of long-term in vitro culturing on CIMM-HCV sequences Samples of PCLB-T4a and PCLBT4b, which had been cultured for months and ... that HCV infects these cells as well, and are produced by them However, it is unknown whether the macrophages are modifying or selecting the HCV to make them more infectious Concentrating the virus ... variety of HCV RNA in patients could result from changes induced in the plasma/sera, including the production of noninfectious viruses We have drawn these conclusions based our studies of CIMMHCV...

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