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How Properties that Distinguish Solids from Fluids and Constraints of Spherical Geometry Suppress Lower Mantle Convection

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Journal of Earth Science 2018年第1期29卷 1-20页

作者： Anne M. Hofmeister Everett M. Criss Department of Earth and Planetary Sciences Washington University St. Louis MO 63130 USA Panasonic Avionics Corporation Lake Forest CA 92630 USA

The large magnitude of the dimensionless Rayleigh number （Ra-10^8） for Earth＇s -3 000 km thick mantle is considered evidence of whole mantle convection. However, the current formulation assumes behavior characteristic of gases and liquids and also assumes Cartesian geometry. Issues arising from neglecting physical properties unique to solids and ignoring the spherical shapes for planets include：（1） Planet radius must be incorporated into Ra, in addition to layer thickness, to conserve mass during radial displacements. （2） The vastly different rates for heat and mass diffusion in solids, which result from their decoupled transport mechanisms, promote stability. （3） Unlike liquids, sub- stantial stress is needed to deform solids, which independently promotes stability. （4） High interior compression stabilizes the mantle in additional minor ways. Therefore, representing conditions for convection in solid, self-gravitating spheroids, requires modifying formulae developed for bottom- heated fluids near ambient conditions under an invariant gravitational field. To derive stability criteria appropriate to solid spheres, we use dimensional analysis, and consider the effects of geometry, force competition, and microscopic behavior. We show that internal heating has been improperly ac- counted for in the Ra. We conclude that the lower mantle is stable for two independent reasons： heat diffusion far outpaces mass diffusion （creep） and yield strength of solids at high pressure exceeds the effective deviatoric stress. We discuss the role of partial melt in lubricating plate motion, and explain why the Ra is not applicable to the multi-component upper mantle. When conduction is insufficient to transport heat in the Earth, melt production and ascent are expected, not convection of solid rock.

关键词： plasticity diffusion mantle convection stability criteria dimensional analysis geometry.

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A Relocation-based Initialization Scheme to Improve Track-forecasting of Tropical Cyclones

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Advances in Atmospheric Sciences 2014年第1期31卷 27-36页

作者： GAO Feng Peter P. CHILDS Xiang-Yu HUANG Neil A. JACOBS Jinzhong MIN Nanjing University of Information Science & Technology National Center for Atmospheric Research Panasonic Avionics Corporation Morrisville Key Laboratory of Meteorological Disaster of the Ministry of Education

A relocation procedure to initialize tropical cyclones was developed to improve the representation of the initial conditions and the track forecast for panasonic Weather Solutions Tropical Operational Forecasts. This scheme separates the vortex perturbation and environment field from the first guess, then relocates the initial vortex perturbations to Lhe observed position by merging them with the environment field. The relationships of wind vector components with stream function and velocity potential are used for separating the vortex disturbance from first guess. For the separation of scalars, a low-pass Barnes filter is employed. The irregular-shaped relocation area corresponding to the specific initial conditions is determined by mapping the edge of the vortex radius in 36 directions.Then, the non-vortex perturbations in the relocation area are removed by a two-pass Barnes filter to retain the vortex perturbations, while the variable fields outside the perimeter of the modified vortex are kept ide.ntical to the original first guess. The potential impacts of this scheme on track forecasts were examined for three hurricane cases in the 2011-12 hurricane season. The experimental results demonstrate that the initialization scheme is able to effectively separate the vortex field from the environment field and maintain a relatively balanced and accurate relocated first guess. As the initial track error is reduced, the following track forecasts are considerably improved. The 72-h average track forecast error was redu,~ed by 32.6% for the cold-start cases, and by 38.4% when using the full-cycling data assimilation because of the accumulatedL improvements from the initialization scheme.

关键词： tropical cyclone vortex relocation data assimilation Barnes filtering

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Overview of Blu-Ray Disc^TM recordable/rewritable media technology

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Frontiers of Optoelectronics 2014年第4期7卷 409-424页

作者： Naoyasu MIYAGAWA AVC Networks Company Panasonic Corporation Kadoma Osaka 5718501 Japan

This paper gives an overview of the research and development progress on Blu-Ray DiscTM （BD） rewritable/recordable media for more than 20 years. The writable BD media had been developed for consumer use like video-recording/personal computer （PC） buck-up and professional use like broadcasting with increasing storage capacity and data rate. The key technology in each innovation was explained according to referenced papers.

关键词： Blu-Ray Disc^TM （BD） optical disc rewritable,recordable write once

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Study on Clutter Model and Characteristics of Airborne Radar with Parabolic Conformal Phased Array

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Journal of Electronic Science and Technology 2016年第1期14卷 49-53页

作者： Hao Jiang Nini Rao Xingbo Chen Jiabin Zhou Chaoyang Qiu Wen Zhai Zhimei Hao the School of Life Science and Technology University of Electronic Science and Technology of Chinachengdu 610054China the Radar and avionics Institute Aviation Industry Corporation of Chinawuxi 214063China

The studies on clutter modeling and suppression of airborne radar with a parabolic conformal array are uncommon due to the complexity of this type of antenna array configuration.The correct understanding of clutter characteristics for airborne radar with a parabolic conformal antenna array is the prerequisite and foundation of optimal suppression of this type of clutter.This paper establishes the model of clutter echo of airborne parabolic conformal phased array radar and analyzes the structure characteristics and the distribution features of this type of clutter.The simulation results show that this type of clutter has the following characteristics：1） The main lobe on the azimuth is seriously broadened,2） the power spectrum presents strong heterogeneity,and 3） the freedom degrees are high.Based on the existing related clutter suppression methods,we verified the correctness of the constructed clutter model.This work has an important guidance to further study on clutter suppression methods in airborne parabolic conformal array radar.

关键词： Airborne radar characteristics clutter parabolic conformal array antenna

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Heterogeneous tunable Ⅲ-Ⅴ-on-silicon-nitride mode-locked laser emitting wide optical spectra

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Photonics Research 2024年第3期12卷 I0021-I0027页

作者： MAXIMILIEN BILLET STIJN CUYVERS STIJN POELMAN ARTUR HERMANS SANDEEP SEEMA SASEENDRA TASUKU NAKAMURA SHINYA OKAMOTO YASUHISA INADA KAZUYA HISADA TAKU HIRASAWA JOAN RAMIREZ DELPHINE NÉEL NICOLAS VAISSIÈRE JEAN DECOBERT PHILIPPE SOUSSAN XAVIER ROTTENBERG GUNTHER ROELKENS JONØ.KJELLMAN BART KUYKEN Photonics Research Group Department of Information TechnologyGhent University-imec9052 GhentBelgium imec 3001 LeuvenBelgium Technology Division Panasonic Holdings CorporationMoriguchi-CityOsakaJapan Ⅲ-Ⅴ Lab F91767 PalaiseauFrance

We demonstrate a Ⅲ-Ⅴ-on-silicon-nitride mode-locked laser through the heterogeneous integration of a semiconductor optical amplifier on a passive silicon-nitride cavity using the technique of micro-transfer printing. In the initial phase of our study, we focus on optimizing the lasing wavelength to be centered at 1550 nm. This optimization is achieved by conducting experiments with 27 mode-locked lasers, each incorporating optical amplifiers featuring distinct multiple-quantum-well photoluminescence values. Subsequently we present a comprehensive study investigating the behavior of the mode-locking regime when the electrical driving parameters are varied. Specifically, we explore the impact of the gain voltage and saturable absorber current on the locking stability of a tunable mode-locked laser. By manipulating these parameters, we demonstrate the precise control of the optical spectrum across a wide range of wavelengths spanning from 1530 to 1580 nm. Furthermore, we implement an optimization approach based on a Monte Carlo analysis aimed at enhancing the mode overlap within the gain region. This adjustment enables the achievement of a laser emitting a 23-nm-wide spectrum while maintaining a defined 10 dB bandwidth for a pulse repetition rate of 3 GHz.

关键词： tunable amplifier mode

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Basic Issues in Localizing Manuals for the Japanese Market

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China Standardization 2010年第2期55卷 18-24页

作者： Toshimasa Yamazaki Product Evaluation Center at panasonic corporation and Chief Councilor of JTCA(Japan Technical Communicators Association)

In today's Japanese market, winning customertrust in companies and their products requires placingever more attention to after-sales service.Forexample, corporate reliability is often decided by thequality of after-sales service when problems occurafter purchase.The world has a wide variety ofproducts and services.For home appliances, operationmanuals that are helpful to the consumer areparticularly important as an aspect of after-salesservice.This paper highlights points that should

关键词：日本市场操作手册售后服务质量本土化可靠性消费者产品

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Surface manipulation of a triple-conducting cathode for protonic ceramic fuel cells to enhance oxygen reduction activity and CO_(2) tolerance

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Journal of Energy Chemistry 2023年第12期87卷 450-459,I0012页

作者： Wenwen Zhang Hiroki Muroyama Yuichi Mikami Toshiaki Matsui Koichi Eguchi Department of Energy and Hydrocarbon Chemistry Graduate School of EngineeringKyoto UniversityNishikyo-kuKyoto 615-8510Japan Technology Division Panasonic Holdings Corporation3-1-1 Yagumo-naka-machiMoriguchi CityOsaka 570-8501Japan

One of the main obstacles limiting the performance of protonic ceramic fuel cells(PCFCs) is the sluggish kinetics of the oxygen reduction reaction(ORR) at reduced temperatures.Here,the surface manipulation of a triple-conducting cathode BaCe_(0.5)Pr_(0.3)Y_(0.2)O_(3-δ)(BCPY) by an efficient catalyst coating PrNi_(0.5)Co_(0.5)O_(3-δ)(PNC) to enhance the ORR activity and CO_(2) tolerance is reported.The developed PNC-coated BCPY cathode achieves the polarization resistance of 0.25 and 1.00 Ω cm^(2) at 600 and 500 ℃,respectively,approximately 1/5 of that for the pristine BCPY cathode(0.99 and 4.79 Ω cm^(2)),while maintaining an excellent CO_(2) tolerance.The single cell on a BaZr_(0.8)Yb_(0.2)O_(3-δ) electrolyte also exhibits a high peak power density of 0.79 W cm^(-2)at 700 ℃ and a stable operation for 200 h at 600 ℃.Such high ORR activity is mainly attributed to the synergistic effect of BCPY support and PNC nanoparticles.Namely,BCPY provides a tripleconducting path(mainly protons),and PNC nanoparticles facilitates surface oxygen exchange and steam adsorption/desorption processes due to the enriched surface oxygen vacancies.This study will provide a new design strategy for developing high-performance PCFCs cathode.

关键词： Triple-conducting cathode Surface manipulation Oxygen reduction reaction CO_(2)tolerance Protonic ceramicfuel cells

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Effects of heat treatment on the microstructures and mechanical properties of a new type of nitrogen-containing die steel

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 511-517页

作者： Jing-yuan Li Peng Zhao Jun Yanagimoto Sumio Sugiyama Yu-lai Chen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Radar and avionics Aviation Industry Corporation of China Suzhou 215151 China Institute of Industrial Science the University of Tokyo Tokyo 153-8505 Japan Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

Nitrogen can increase the strength of steels without weakening the toughness and improve the corrosion resistance at the same time. Compared with conventional nitrogen-free die steels, a new type of nitrogen-containing die steel was developed with many superior properties, such as high strength, high hardness, and good toughness. This paper focused on the effects of heat treatment on the microstruc- tures and mechanical properties of the new type of nitrogen-containing die steel, which were investigated by the optimized deformation process and heat treatment. Isothermal spheroidal annealing and high-temperature quenching as well as high-temperature tempering were ap- plied in the experiment by means of an orthogonal method after the steel was multiply forged. The mechanical properties of nitro- gen-containing die steel forgings are better than the standard of NADCA #207-2003.

关键词： die steels nitrogen heat treatment microstructure mechanical properties forgings

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Downscaling GCMs Using the Smooth Support Vector Machine Method to Predict Daily Precipitation in the Hanjiang Basin

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Advances in Atmospheric Sciences 2010年第2期27卷 274-284页

作者：陈华郭靖熊伟郭生练 Chong-Yu XU State Key Laboratory o/Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 Department of Geosciences University of Oslo PO Box 1047 Blindern NO-0316 Oslo Nomvay Radar and avionics Institute of Aviation Industry corporation of China Wuxi 214063

General circulation models （GCMs） are often used in assessing the impact of climate change at global and continental scales. However, the climatic factors simulated by GCMs are inconsistent at comparatively smaller scales, such as individual river basins. In this study, a statistical downscaling approach based on the Smooth Support Vector Machine （SSVM） method was constructed to predict daily precipitation of the changed climate in the Hanjiang Basin. NCEP/NCAR reanalysis data were used to establish the statistical relationship between the larger scale climate predictors and observed precipitation. The relationship obtained was used to project future precipitation from two GCMs （CGCM2 and HadCM3） for the A2 emission scenario. The results obtained using SSVM were compared with those from an artificial neural network （ANN）. The comparisons showed that SSVM is suitable for conducting climate impact studies as a statistical downscaling tool in this region. The temporal trends projected by SSVM based on the A2 emission scenario for CGCM2 and HadCM3 were for rainfall to decrease during the period 2011–2040 in the upper basin and to increase after 2071 in the whole of Hanjiang Basin.

关键词： SSVM GCM statistical downscaling precipitation Hanjiang Basin

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Electron Spin Resonance Analyse on the Production of Hydroxyl Radicals by Ozone Photolysis

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Journal of Shanghai Jiaotong university(Science) 2010年第4期15卷 458-462页

作者：高利利程金平刘元嫄殷永文 OKETA Takemi HORIBATA Fumie School of Environmental Science and Engineering Shanghai Jiaotong University Corporate Engineering Division Home Appliances CompanyPanasonic Corporation

In order to explore the production of hydroxyl radical(·OH)in a confined space,a novel ozone-light irradiation system is constructed in this study,and the·OH radical is measured by spin-trapping electron spin resonance(ESR)method in which 5,5-dimethyl-1-pyrroline-N-oxide(DMPO)is selected as the spin-trap.Several influence factors including the light intensity,the irradiation time and DMPO mass concentration are discussed. The results show that in this experimental system,with DMPO mass concentration of 1g/L and the irradiation time of 30 min,the·OH radical can be best captured.Besides,both wavelength and intensity of the irradiation light could effect the generation of·OH radical.These results are of great importance to further study the sterilization effect of·OH radical in confined space.

关键词： electron spin resonance(ESR) hydroxyl radicals ozone photolysis

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