How has Japan become a major economic power, a world leader in the automotive and electronics industries? What is the secret of their success? The consensus has been that, though the Japanese are not particularly innovative, they are exceptionally skilful at imitation, at improving products that already exist. But now two leading Japanese business experts, Ikujiro Nonaka and Hiro Takeuchi, turn this conventional wisdom on its head: Japanese firms are successful, they contend, precisely because they are innovative, because they create new knowledge and use it to produce successful products and technologies. Examining case studies drawn from such firms as Honda, Canon, Matsushita, NEC, 3M, GE, and the U.S. Marines, this book reveals how Japanese companies translate tacit to explicit knowledge and use it to produce new processes, products, and services.

The knowledge-creating company : how Japanese companies create the dynamics of innovation

Matrix Factorization Techniques for Recommender Systems

Condition monitoring of induction motors is a fast emerging technology for online detection of incipient faults. It avoids unexpected failure of a critical system. Approximately 30-40% of faults of induction motors are stator faults. This work presents a comprehensive review of various stator faults, their causes, detection parameters/techniques, and latest trends in the condition monitoring technology. It is aimed at providing a broad perspective on the status of stator fault monitoring to researchers and application engineers using induction motors. A list of 183 research publications on the subject is appended for quick reference.

A review of stator fault monitoring techniques of induction motors

With rapid electrification of transportation, it is becoming increasingly important to have a comprehensive understanding of criteria used in motor selection. This paper presents the design and comparative evaluation for an interior permanent magnet synchronous motor (IPMSM) with distributed winding and concentrated winding, induction motor (IM), and switched reluctance motor (SRM) for an electric vehicle (EV) or hybrid electric vehicle (HEV) application. A fast finite element analysis (FEA) modeling approach is addressed for IM design. To account for highly nonlinear motor parameters and achieve high motor efficiency, optimal current trajectories are obtained by extensive mapping for IPMSMs and IM. Optimal turn- on and turn- off angles with current chopping control and angular position control are found for SRM. Additional comparison including noise vibration and harshness (NVH) is also highlighted. Simulation and analytical results show that each motor topology demonstrates its own unique characteristic for EVs/HEVs. Each motor’s highest efficiency region is located at different torque-speed regions for the criteria defined. Stator geometry, pole/slot combination, and control strategy differentiate NVH performance.

Comparative Study of Interior Permanent Magnet, Induction, and Switched Reluctance Motor Drives for EV and HEV Applications

A complex infrastructure is usually a reality in a virtual enterprise. For these enterprises to operate well they would need notions of workflows, global and local business processes, Service Level Agreements, and business transactions. Web Service Standards such as SOAP, WSDL, and BPEL4WS make virtual enterprise increasingly practical, speeding up the flow of business and reducing costs. These web services have to be interfaced with the internal business processes. The interchange of service results in the interaction of existing business processes and results in new distributed processes.

技術解説 IEEE Internet Computing

GENERATION AND RADIATION OF NOISE IN ELECTRICAL MACHINES Vibration, Sound, and Noise Sound Waves Sources of Noise in Electrical Machines Energy Conversion Process Noise Limits and Measurement Procedures for Electrical Machines Deterministic and Statistical Methods of Noise Prediction Economical Aspects Accuracy of Noise Prediction MAGNETIC FIELDS AND RADIAL FORCES IN POLYPHASE MOTORS FED WITH SINUSOIDAL CURRENTS Construction of Induction Motors Construction of Permanent Magnet Synchronous Brushless Motors A.C. Stator Windings Stator Winding MMF Rotor Magnetic Field Calculation of Air Gap Magnetic Field Radial Forces Other Sources of Electromagnetic Vibration and Noise INVERTER-FED MOTORS Generation of Higher Time Harmonics Analysis of Radial Forces for Nonsinusoidal Currents Higher Time Harmonic Torques in Induction Machines Higher Time Harmonic Torques in Permanent Magnet (PM) Brushless Machines Influence of the Switching Frequency of an Inverter Noise Reduction of Inverter-Fed Motors TORQUE PULSATIONS Analytical Methods of Instantaneous Torque Calculation Numerical Methods of Instantaneous Torque Calculation Electromagnetic Torque Components Sources of Torque Pulsations Higher Harmonic Torques of Induction Motors Cogging Torque in Permanent Magnet (PM) Brushless Motors Torque Ripple Due to Distortion of EMF and Current Waveforms in Permanent Magnet (PM) Brushless Motors Tangential Forces vs. Radial Forces Minimization of Torque Ripple in PM Brushless Motors STATOR SYSTEM VIBRATION ANALYSIS Forced Vibration Simplified Calculation of Natural Frequencies of the Stator System Improved Analytical Method of Calculation of Natural Frequencies Numerical Verification ACOUSTIC CALCULATIONS Sound Radiation Efficiency Plane Radiator Infinitely Long Cylindrical Radiator Finite Length Cylindrical Radiator Calculations of Sound Power Level NOISE AND VIBRATION OF MECHANICAL AND AERODYNAMIC ORIGIN Mechanical Noise Due to Shaft and Rotor Irregularities Bearing Noise Noise Due to Toothed Gear Trains Aerodynamic Noise Mechanical Noise Generated by the Load ACOUSTIC AND VIBRATION INSTRUMENTATION Measuring System and Transducers Measurement of Sound Pressure Acoustic Measurement Procedure Vibration Measurements Frequency Analyzers Sound Power and Sound Pressure Indirect Methods of Sound Power Measurement Direct Method of Sound Power Measurement: Sound Intensity Technique Standard for Testing Acoustic Performance of Rotating Electrical Machines NUMERICAL ANALYSIS Introduction FEM Model for Radial Magnetic Pressure FEM for Structural Modeling BEM for Acoustic Radiation Discussion STATISTICAL ENERGY ANALYSIS Introduction Power Flow Between Linearly Coupled Oscillators Coupled Multimodal Systems Experimental SEA Application to Electrical Motors NOISE CONTROL Mounting Standard Methods of Noise Reduction Active Noise and Vibration Control APPENDIX A: BASICS OF ACOUSTICS Sound Field Variables and Wave Equations Sound Radiation from a Point Source Decibel Levels and Their Calculations Spectrum Analysis APPENDIX B: PERMEANCE OF NONUNIFORM AIR GAP Permeance Calculation Eccentricity Effect APPENDIX C: MAGNETIC SATURATION APPENDIX D: BASICS OF VIBRATION A Mass-Spring-Damper Oscillator Lumped Parameter Systems Continuous Systems SYMBOLS AND ABBREVIATIONS BIBLIOGRAPHY INDEX

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Noise of polyphase electric motors

Tumor-associated macrophages (TAMs) play an essential role in metastasis. However, what enables TAMs to have a superior capacity to establish pre-metastatic microenvironment in distant organs is unclear. Here we have begun to uncover the effects of cytochrome P450 (CYP) 4A in TAMs on lung pre-metastatic niche formation and metastasis. CYP4A+ TAM infiltration was positively associated with metastasis, pre-metastatic niche formation and poor prognosis in breast cancer patients. The pharmacological inhibition of CYP4A reduced lung pre-metastatic niche formation (evidenced by a decrease in vascular endothelial growth factor receptor 1 positive (VEGFR1+) myeloid cell recruitment and pro-metastatic protein expression) and metastatic burden, accompanied with TAM polarization away from the M2 phenotype in spontaneous metastasis models of 4T1 breast cancer and B16F10 melanoma. Co-implantation of 4T1 cells with CYP4A10high macrophages promoted lung pre-metastatic niche formation and metastasis. Depletion of TAMs disrupted lung pre-metastatic niches and thereby prevented metastasis. Treatment with the CM from CYP4A10high M2 macrophages (M2) increased pre-metastatic niche formation and metastatic burden in the lungs, whereas CYP4A inhibition attenuated these effects. In vitro TAM polarization away from the M2 phenotype induced by CYP4A inhibition decreased VEGFR1+ myeloid cell migration and fibronectin expression, accompanied with downregulation of STAT3 signaling. Conversely, overexpression of CYP4A or exogenous addition of 20-hydroxyeicosatetraenoic acid promoted M2 polarization and cytokine production of macrophages and thereby enhanced migration of VEGFR1+ myeloid cells, which were reversed by siRNA or pharmacological inhibition of STAT3. Importantly, a combined blocking M2 macrophage-derived factors TGF-β, VEGF and SDF-1 abolished VEGFR1+ myeloid cell migration and fibroblast activation induced by CYP4A. In summary, CYP4A in TAMs is crucial for lung pre-metastatic niche formation and metastasis, and may serve as a potential therapeutic target in human cancer.

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Chong Wang

Papers

Noise of polyphase electric motors

CYP4A in tumor-associated macrophages promotes pre-metastatic niche formation and metastasis.

Prediction of natural frequencies of finite length circular cylindrical shells

Vibration analysis of an induction motor

The sound radiation efficiency of finite length acoustically thick circular cylindrical shells under mechanical excitation i: theoretical analysis