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排灌机械工程学报 2014年第12期32卷 1013-1022页

作者： Cooper Paul Fluid Machinery Research Inc. TitusvilleNew Jersey 08560USA

An overview of some popular rotary and reciprocating positive displacement( PD) pump types is given with the objective of presenting and comparing the respective sizing relationships and performance features. Reciprocating pumps discussed are the piston and plunger types. Rotary pumps addressed are gear( external and internal),vane,lobe,screw,and liquid ring pumps. To put the relative pump sizes in perspective,attention is fixed on the rotors or reciprocating elements of PD pumps,just as impellers indicate the sizes of rotodynamic pumps. The size of a PD pump is found from a dimensionless combination of displacement flow rate,rotative speed and diameter. The flow rate,head( or pressure rise) and power are related through the component efficiencies. The cavitation coefficient,often close to unity,connects the rotor tip speed or piston speed with the required NPSH,which can also be affected by the pressure rise of the pump due to leakage across the internal clearances. Operational effects due to cavitation,ingestion of gas or abrasives,and viscous and non-Newtonian fluids are discussed.

关键词： positive displacement pumps rotary reciprocating rotor sizing required NPSH

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

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Journal of Semiconductors 2006年第4期27卷 635-640页

作者： Pinsukanjana P Vargason K Herrera M Ontiveros D Boehme C Intelligent Epitaxy Technology Inc.RichardsonTX 75081USA

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4×100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors inc.uding an absorption band edge spectroscope and an optical-based flux *** state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb.A Sb composition variation of less than ±0.1 atomic percent across a 4×100mm platen configuration has been *** large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BV_CEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm×50μ*** devices have a 40nm thick GaAsSb base with p-doping of 4.5×*** with an emitter size of 4μm×30μm have a current gain variation less than 2% across the fully processed 100mm wafer.f_t and f_max are over 50GHz,with a power efficiency of 50%,which are comparable to standard power GaAs HBT *** results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.

关键词： InP GaAsSb 多晶片产品传感器

The Paradigm of power Bounded High-Performance Computing

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Journal of Computer Science & Technology 2023年第1期38卷 87-102页

作者： Rong Ge Xizhou Feng Pengfei Zou Tyler Allen School of Computing Clemson UniversityClemsonSC 29634U.S.A. Meta Platform Inc.Menlo ParkCA 94025U.S.A. Amazon Inc.SeattleWA 98170U.S.A. University of North Carolina at Charlotte NC 27599U.S.A.

Modern computer systems are inc.easingly bounded by the available or permissible power at multiple layers from individual components to data *** cope with this reality,it is necessary to understand how power bounds im-pact performance,especially for systems built from high-end nodes,each consisting of multiple power hungry *** placing an inappropriate power bound on a node or a component can lead to severe performance loss,coordinat-ing power allocation among nodes and components is mandatory to achieve desired performance given a total power *** this article,we describe the paradigm of power bounded high-performance computing,which considers coordinated power bound assignment to be a key factor in computer system performance analysis and *** apply this paradigm to the problem of power coordination across multiple layers for both CPU and GPU *** several case studies,we demonstrate how the princ.ples of balanced power coordination can be applied and adapted to the inter-play of workloads,hardware technology,and the available total power for performance improvement.

关键词： power bounded computing cross-component power coordination hierarchical power allocation

Graph Computing Based Security Constrained Unit Commitment in Hydro-thermal power Systems inc.rporating Pumped Hydro Storage

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CSEE Journal of power and Energy Systems 2021年第3期7卷 485-496页

作者： Longfei Wei Guangyi Liu Shen Yan Renchang Dai Yachen Tang Hitachi ABB power Grids San JoseCAUSA School of Electrical Engineering Xi'an University of TechnologyXi'anChina Department of Industrial and Enterprise Systems Engineering University of Illinois at Urbana-ChampaignChampaignILUSA Puget Sound Energy BellevueWAUSA Envision Digital inc. Redwood CityCAUSA

This paper proposes a graph computing based mixed integer programming(MIP)framework for solving the security constrained unit commitment(SCUC)problem in hydro-thermal power systems inc.rporating pumped hydro storage(PHS).The proposed graph computing-based MIP framework considers the economic operations of thermal units,cascade hydropower stations and PHS stations,as well as their technical impacts towards the network ***,the hydro-thermal power system data and unit information are stored in a graph structure with nodes and edges,which enables nodal and hierarchical parallel computing for the unit commitment(UC)solution calculation and network security analysis.A MIP model is then formulated to solve the SCUC problem with the mathematical models of thermal units,cascade hydropower stations and PHS *** addition,two optimization approaches inc.uding convex hull reformulation(CHR)and special ordered set(SOS)methods are introduced for speeding up the MIP calculation *** ensure the system stability under the derived UC solution,a parallelized graph power flow(PGPF)algorithm is proposed for the hydro-thermal power system network security ***,case studies of the IEEE 118-bus system and a practical 2749-bus hydro-thermal power system are introduced to demonstrate the feasibility and validity of the proposed graph computing-based MIP framework.

关键词： Graph computing hydro-thermal system mixed integer programming network security unit commitment

Angular-modulated spatial distribution of ultrahigh-order modes assisted by random scattering

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Chinese Physics B 2017年第11期26卷 254-257页

作者：阚雪芬殷澄许田陈凡李建韩庆邦陈险峰 Jiangsu Key Laboratory of power Transmission and Distribution Equipment Technology Hohai University The State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems Department of Physics and Astronomy Shanghai Jiao Tong University Physics Department Nantong University Optoelectronics Devices Laboratory Photonlabs Inc.

In designing an optical waveguide with metallic films on a nanometer scale, the random scattering by the natural roughness of the thin film is always ignored. In this paper, we demonstrate that for the ultrahigh-order modes（UOMs） in the symmetric metal cladding waveguide, such a scattering leads to drastic variations in their spatial distribution at different inc.dent angles. Owing to the high mode density of the UOMs, the random scattering induced coupling can be easily related to different modes with different propagation directions or wavenumbers. At small inc.dent angles, the intra-mode coupling dominates, which results in a spatial distribution in the form of concentric rings. At large inc.dent angles, the inter-mode coupling plays the most important role and leads to an array-like pattern. Experimental evidence via optically trapped nanoparticles support the theoretical hypothesis.

关键词： metallic waveguide random scattering optical trapping

Type Selection of Burning Equipment for Low Volatile Coal Boilers

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Electricity 2012年第2期23卷 31-36页

作者： Li Weidong Zhou Hongguang Xu Dangqi Zhang Jingwu Xu Chuankai Huaneng power International inc. Xi'an Thermal power Research Institute Co. Ltd. Northeast Electric power Research Institute Co. Ltd.

When designing and selecting burning equipment for low volatile coal fired boilers,the primary concerns are about coal ignition and *** characteristics of ignition and burnout are analyzed for low volatile coal and the technical measures are discussed for enhancing the combustion and *** adaptability of tangential firing,wall firing and double-arch firing for low volatile coal is *** on the statistic analysis for the main design parameters of domestic low volatile coal fired boilers with tangential firing,wall firing or double-arch W flame firing,the thermal performance for various boiler furnaces is *** combustion systems for different types of boilers are also put forward for coals with different volatiles.

关键词： burning equipment low volatile coal type selection

Post-combustion slipstream CO_(2)-capture test facility at Jiangyou power Plant, Sichuan, China: performance of a membrane separation module under dynamic power-plant operations

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clean Energy 2021年第4期5卷 742-755页

作者： Qian Cui Baodeng Wang Xinglei Zhao Guoping Zhang Zhendong He Yinhua Long Yongwei Sun Anthony Y.Ku National Institute of clean-and-Low-Carbon Energy Beijing 102209P.R.China Guoneng Jiangyou Thermal power Co. LtdSichuanP.R.China NICE America Research Mountain ViewCA 94043USA

Membrane-based separation technologies have the potential to lower the cost of post-combustion CO_(2) capture from power-plant flue gases through reduced energy and capital costs relative to conventional solvent *** have shown promise under controlled conditions,but there is a need for data on performance and reliability under field ***-fired power plants in China operate in a dynamic manner,with inc.eases and decreases in output causing changes in flue-gas *** this paper,we describe the first field test of a membrane-based post-combustion CO_(2)-capture system connected to a dynamically operating power plant in *** report the performance of a Membrane Technology Research,inc.(MTR)Polaris^(TM) membrane-based capture system over a range of plant operating loads ranging from 54%to 84%and conducted an operational stability test over a 168-h period during which the power plant was operating at an average load of 55%,but ramped as high as 79%and as low as 55%.Our results confirm the ability of a membrane capture system to operate effectively over a wide range of host-plant operating conditions,but also identity several issues related to plant integration,system control and resilience in the face of host-plant upsets that require attention as membrane separation systems move towards commercial use.

关键词： China CO_(2)capture membrane coal power post-combustion capture

Analysis of power Model for Linear Plasma Device

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Plasma Science and Technology 2016年第8期18卷 844-847页

作者：张卫卫邓柏权左浩毅曾宪俊曹小岗薛晓艳欧巍曹智芶富均 College of Physical Science and Technology or Institute of Nuclear Science and Technology Sichuan University Southwestern Institute of Physics HOPE Innovations inc.

A single cathode linear plasma device has been designed and constructed to investigate the interactions between plasma and materials at the Sichuan University. In order to further investigate the Ohmic power of the device, the output heat load on the specimen and electric potential difference（between cathode and anode） have been tested under different discharge currents. This special power distribution in the radial direction of the plasma discharge channel has also been discussed and described by some improved integral equations in this paper;it can be further simplified as P ∝ α^（-2） in one-parameter. Besides, we have measured the power loss of the channel under different discharge currents by the calorimetric method, calculated the effective power of the device and evaluated the performances of the plasma device through the power efficiency analysis.

关键词： plasma resistivity power conversion efficiency

Flaw Detection Capability and Sensitivity in the Inspection of Nuclear Containment Liner and Shell Mock-Ups Utilizing a Magnetostrictive Sensor (MsS) Guided Wave UT Technique

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Journal of Modern Physics 2014年第13期5卷 1173-1185页

作者： Brian P. Hohmann Joseph P. Crosson Thomas C. Esselman James J. Wall Mike Quarry Luke Breon Electric power Research Institute Charlotte NC USA LPI Inc. New York NY USA

This paper describes the results of a project on the inspection of visually inaccessible areas of nuclear containment liners and shells via the advanced Magnetostrictive sensor (MsS) Guided Wave (GW) nondestructive inspection technique. Full scale mockups that simulated shell and liner regions of interest in the containment of both a Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) were constructed. Inspections were performed on the mock-ups in three stages to discern the signal attenuation caused by flaws and caused by concrete in the structures. The effect of concrete being in close proximity to the liner and shell was determined, and the capability to detect and size flaws via this GW technique was evaluated.

关键词： Ultrasonic Guided Wave Nondestructive Inspection Nuclear Containment Concrete Mockup Flaw Detection Magnetostrictive Sensor Pressurized Water Reactor Boiling Water Reactor