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Simulation on Reliability Enhancement Testing Technology of Ramming System
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作者 胡慧斌 曹立军 +1 位作者 陈树肖 马吉胜 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第4期477-481,共5页
Ramming system is the key device to guarantee the firing speed of self-propelled gun. Based on traditional reliability enhancement testing method, a new kind of reliability enhancement testing simulation method of ram... Ramming system is the key device to guarantee the firing speed of self-propelled gun. Based on traditional reliability enhancement testing method, a new kind of reliability enhancement testing simulation method of ramming system is put forward firstly. In CAD software Pro/E and dynamic simulation software ADAMS, the virtual prototype of ramming system is established. In EASY5 software, the corresponding hydraulic system and control system models are built. The reliability enhancement testing virtual environment of ramming system is developed using the mechanical-electrical-hydraulic co-simulation technology. Based on the load spectra provided by virtual prototype, and the stress distribution provided by finite element analysis and material's S-N curve(S is fatigue strength, N is fatigue life), a model of fatigue enhancement coefficient is established through the failure mechanism analysis. The simulation processes and simulation results show the feasibility of reliability enhancement testing based on virtual prototype, and provide sufficient theory reference for structure improvement and optimization of ramming system. 展开更多
关键词 ramming system virtual prototype reliability enhancement testing FATIGUE
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基于CPLD和Embedded System的LED点阵显示系统的实现 被引量:1
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作者 谢敏 黄海星 +1 位作者 陈广贤 覃团发 《电子技术应用》 北大核心 2004年第10期63-66,共4页
采用自顶向下的设计思想,综合运用EDA技术、CPLD技术和共享式双口RAM,解决了大屏幕LED点阵显示屏无闪烁显示的技术难题。给出了系统设计方法及实际电路。
关键词 LED点阵 CPLD 大屏幕 EDA技术 闪烁 显示系统 显示屏 自顶向下 共享 双口RAM
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数字式压力传感器在呼吸机典型案例分析
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作者 王亮 于杰 +1 位作者 王皖青 吴磊军 《生物医学工程与临床》 2026年第1期99-104,共6页
数字式压力传感器[1]的工作原理是基于前端模拟部件的压电效应,压电材料在受到外力作用时会发生形变,由此产生电荷。传感器内置的电桥测量这些电荷的大小,并将其转换为电信号。该信号由数字信号调节器[2,3]内置的运算放大器运算处理,之... 数字式压力传感器[1]的工作原理是基于前端模拟部件的压电效应,压电材料在受到外力作用时会发生形变,由此产生电荷。传感器内置的电桥测量这些电荷的大小,并将其转换为电信号。该信号由数字信号调节器[2,3]内置的运算放大器运算处理,之后将其输入到内部的模拟-数字转换器(analog to digital converter,A/D)中,将模拟信号转换为数字信号输出。最后,这些数字信号由微控制器处理机显示,以获取压力测量结果。 展开更多
关键词 数字压力传感器 信号调节器 RAM EEPROM 校准 替代方案
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人工智能技术驱动轨道交通设备预测性维护模型构建
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作者 郭眉 《中国设备工程》 2026年第5期26-28,共3页
城市化进程提速,城市轨道交通已然成为公共交通体系的核心支柱,其设备运行的安全可靠,直接影响公众出行安全及运输效率。预测性维护依托状态感知实现精准维护,可提前预判设备故障风险,是先进的维护理念,而人工智能技术的兴起,为该模式... 城市化进程提速,城市轨道交通已然成为公共交通体系的核心支柱,其设备运行的安全可靠,直接影响公众出行安全及运输效率。预测性维护依托状态感知实现精准维护,可提前预判设备故障风险,是先进的维护理念,而人工智能技术的兴起,为该模式落地提供核心技术支撑。本文聚焦轨道交通设备预测性维护,先剖析当前实践核心问题,再梳理AI驱动该模型构建的关键技术体系;继而结合RAMS管理指标完成模型整体设计,最后详细阐述其构建流程与实现路径。 展开更多
关键词 人工智能 轨道交通设备 预测性维护 RAMS指标 模型构建
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Charge Structure of a Summer Thunderstorm in North China:Simulation Using a Regional Atmospheric Model System 被引量:19
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作者 LIU Dongxia QIE Xiushu +1 位作者 PENG Liang LI Wanli 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第5期1022-1034,共13页
Electrification and simple discharge schemes are coupled into a 3D Regional Atmospheric Model System (RAMS) as microphysical parameterizations, in accordance with electrical experiment results. The dynamics, microph... Electrification and simple discharge schemes are coupled into a 3D Regional Atmospheric Model System (RAMS) as microphysical parameterizations, in accordance with electrical experiment results. The dynamics, microphysics, and electrifi- cation components are fully integrated into the RAMS model, and the inductive and non-inductive electrification mechanisms are considered in the charging process. The results indicate that the thunderstorm mainly had a normal tripole charge structure. The simulated charge structure and lightning frequency are basically consistent with observations of the lightning radiation source distribution. The non-inductive charging mechanism contributed to the electrification during the whole lifetime of the thunderstorm, while the inductive electrification mechanism played a significant role in the development period and the mature stage when the electric field reached a large value. The charge structure in the convective region and the rearward region are analyzed, showing that the charge density in the convective region was double that in the rearward region. 展开更多
关键词 RAMS electrification parameterization discharge parameterization charge structure THUNDERSTORM
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An Application of the RAMS/FLUENT System on the Multi-Scale Numerical Simulation of the Urban Surface Layer—A Preliminary Study 被引量:11
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作者 李磊 胡非 +1 位作者 姜金华 程雪玲 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第2期271-280,共10页
The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL)... The Regional Atmospheric Modeling System (RAMS) and the computational fluid dynamics (CFD) codes known as FLUENT are combinatorially applied in a multi-scale numerical simulation of the urban surface layer (USL). RAMS and FLUENT are combined as a multi-scale numerical modeling system, in which the RAMS simulated data are delivered to the computational model for FLUENT simulation in an offline way. Numerical simulations are performed to present and preliminarily validate the capability of the multi-scale modeling system, and the results show that the modeling system can reasonably provide information on the meteorological elements in an urban area from the urban scale to the city-block scale, especially the details of the turbulent flows within the USL. 展开更多
关键词 multi-scale numerical simulation urban surface layer (USL) urban canopy layer (UCL) RAMS/FLUENT system
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Design and reliability,availability,maintainability,and safety analysis of a high availability quadruple vital computer system 被引量:5
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作者 Ping TAN Wei-ting HE +2 位作者 Jia LIN Hong-ming ZHAO Jian CHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2011年第12期926-935,共10页
With the development of high-speed railways in China,more than 2000 high-speed trains will be put into use.Safety and efficiency of railway transportation is increasingly important.We have designed a high availability... With the development of high-speed railways in China,more than 2000 high-speed trains will be put into use.Safety and efficiency of railway transportation is increasingly important.We have designed a high availability quadruple vital computer (HAQVC) system based on the analysis of the architecture of the traditional double 2-out-of-2 system and 2-out-of-3 system.The HAQVC system is a system with high availability and safety,with prominent characteristics such as fire-new internal architecture,high efficiency,reliable data interaction mechanism,and operation state change mechanism.The hardware of the vital CPU is based on ARM7 with the real-time embedded safe operation system (ES-OS).The Markov modeling method is designed to evaluate the reliability,availability,maintainability,and safety (RAMS) of the system.In this paper,we demonstrate that the HAQVC system is more reliable than the all voting triple modular redundancy (AVTMR) system and double 2-out-of-2 system.Thus,the design can be used for a specific application system,such as an airplane or high-speed railway system. 展开更多
关键词 Fault tolerant High availability quadruple vital computer (HAQVC) RELIABILITY AVAILABILITY MAINTAINABILITY and safety (RAMS)
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Sintering Behaviour of Al_2O_3-SiC-C Ramming Mix
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作者 WUXingrong CAOFeng 《China's Refractories》 CAS 2004年第2期33-36,共4页
Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties a... Silicon fines, boron acid solid powders and microfine SiO 2 as sintering agents were incorporated into Al 2O 3-SiC-C ramming mix in order to investigated their effects on the microstructure, mechanical properties and sintering behavior of the ramming mix. Results show that all the three agents could improved both densification and mehanical properties markedly, compared to that of non-agent specimens and the effect of the composite of boron acid solid powders and microfine SiO 2 is the best. The oxidation resistance increased with the addition of agents, which is supported by densification. Microstructures showed that agent powders could fill pores or produce liquid phases at high temperature, therefore, improve the sintering of the ramming mix. 展开更多
关键词 ALUMINA Silicon carbide Carbon ramming mix Sintering agent DENSIFICATION Oxidation resistance
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Environmental-friendly Ramming Materials for Mud Package and Taphole of Large-scaled Blast Furnaces
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作者 XU Guotao LI Huaiyuan +1 位作者 CHEN Xilai ZHANG Honglei 《China's Refractories》 CAS 2013年第4期5-8,共4页
The compositions, structures and properties of envi- ronmental-friendly ramming materials for mud package and taphole of large-scaled blast furnaces were studied. The results show that the formation of silica fibers m... The compositions, structures and properties of envi- ronmental-friendly ramming materials for mud package and taphole of large-scaled blast furnaces were studied. The results show that the formation of silica fibers makes structure of ramming materials dense. During the process of extruding mud and ramming materials, SiC is partly oxidized ; CaO , F% 03 and carbon penetrate towards the outer wall. The improvement of ramming materials can inhibit the penetration of molten slag, iron and carbon. The bulk density of environmental-friendly ramming ma- terials dried at 200 ℃ is 2.90 g · cm-3, the cold com- pressive strength of this kind of ramming materials dried at 200 ℃ is about 17. 0 MPa and fired at I 450 ℃ is about 39. 2 MPa. 展开更多
关键词 blast furnace mud package TAPHOLE ramming material environmental-friendly
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High Speed Network Intrusion Detection System(NIDS)Using Low Power Precomputation Based Content Addressable Memory
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作者 R.Mythili P.Kalpana 《Computers, Materials & Continua》 SCIE EI 2020年第3期1097-1107,共11页
NIDS(Network Intrusion Detection Systems)plays a vital role in security threats to computers and networks.With the onset of gigabit networks,hardware-based Intrusion Detection System gains popularity because of its hi... NIDS(Network Intrusion Detection Systems)plays a vital role in security threats to computers and networks.With the onset of gigabit networks,hardware-based Intrusion Detection System gains popularity because of its high performance when compared to the software-based NIDS.The software-based system limits parallel execution,which in turn confines the performance of a modern network.This paper presents a signature-based lookup technique using reconfigurable hardware.Content Addressable Memory(CAM)is used as a lookup table architecture to improve the speed instead of search algorithms.To minimize the power and to increase the speed,pre-computation based CAM(PBCAM)can be used,as this technique avoids repeated search comparisons.PBCAM employs the two-stage comparison with a parameter memory in the first stage and data memory in the second stage.Only the matched data in the parameter memory are compared in the data memory.This reduces the number of comparisons,thereby increasing the speed of the system.In this work dual-port RAM-based PBCAM(DP-PBCAM)is used to design a signature-based intrusion detection system.A low power parameter extractor is used with a minimum number of gates for precomputation.The hardware implementation is done using Xilinx Spartan 3E FPGA.The proposed DP-PBCAM lookups support a gigabit-speed of 7.42 Gbps. 展开更多
关键词 NIDS FPGA dual port RAM CAM PBCAM DP-PBCAM
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Influence of Raw Material on the Properties of MgO-Al_2O_3-Cr_2O_3 Ramming Mixes
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作者 YANG Leqin, WANG Li, LIN Wanruo, YANG Zhibin and ZHANG Fengli(Luoyang Refractory Group Co. , Ltd. Luoyang,Henan 471039 China) 《China's Refractories》 CAS 2002年第3期18-27,共10页
Mg0-Al2O3-Cr2O3 ramming mixes made of different raw materials have different mineral structure and different physical properties though with the identical particle size distribution, the same amount of binder and chem... Mg0-Al2O3-Cr2O3 ramming mixes made of different raw materials have different mineral structure and different physical properties though with the identical particle size distribution, the same amount of binder and chemical composition . The residual carbon content of the fused magnesia-chrome material made in reducing atmosphere is very high, if this material is used in the MgO-Al203-Cr2O3 ramming mix , it would cause spalling of the furnace lining during drying-out. 展开更多
关键词 ramming mix Raw material Magnesia-alumina-chrome system
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Effect of Magnesia-Chrome Synthetic Materials on Magnesia-Alumina-Chrome Ramming Mixes
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作者 WANG Li ZHANG Xiaohui +1 位作者 ZHANG Chenqian JIANG Mingxue 《China's Refractories》 CAS 2006年第3期24-27,共4页
Magnesia-alumina-chrome ramming mixes with same chemical compositions were prepared by using different raw materials such as fused magnesia-chrome synthetic materials and sintered one, wasted bricks and magnesia-alumi... Magnesia-alumina-chrome ramming mixes with same chemical compositions were prepared by using different raw materials such as fused magnesia-chrome synthetic materials and sintered one, wasted bricks and magnesia-alumina spinels. Their physical properties were tested and microstructures were analyzed. The results show that the ramming mixes made of different raw materials bring about different microstructures and properties although the mixes have the same chemical composition, binder content and aggregate size composition. 展开更多
关键词 Magnesia-chrome synthetic materials ramming mix Magnesia-alumina-chrome
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Advanced Ramming Mix Based on Fused Zirconia Stabilized by Com-bined Additives of CaO and MgO for Lining of Carbon Black Production Reactor
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作者 Valeriy V.MARTYNENKO Vladimir V.PRIMACHENKO +3 位作者 Irina G.SHULIK Dmitriy A.SHISHKOVSKIY Eleonora L.KARYAKINA Vladimir V.VARGANOV 《China's Refractories》 CAS 2017年第3期1-7,共7页
Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made. With using chemical, petrographic, X-ray phase and electron microscopic researches the main characterist... Fused materials from ZrO2 stabilized by CaO or MgO, or the combined additive consisting of CaO and MgO are made. With using chemical, petrographic, X-ray phase and electron microscopic researches the main characteristics of these materials are determined. It is shown that, the materials of all compositions have low water absorption; they are characterized by equal struc-ture. The materials stabilized by the combined additive consisting of CaO and MgO are presented by generally the cubic phase and a small amount of tetragonal and monoclinic ZrO2 phases. Depending on CaO: MgO ratio in the materials the tetragonal ZrO2 phase settles down in a cubic matrix in the form of separate grains, and sites of net like structure in the form of a "woven" interlacing (2.9% of CaO and 2. 6% of MgO ). An influence of the above mentioned fused stabilized ZrO2 materials and quantity of monoclinic zirconia, on the forming of zirconia mix on a phosphate bond and properties of" .fired samples is studied. The samples from mix based on ZrO2 stabilized by the combined additive consisting of 2.9% CaO and 2.6% MgO with 20% of monoclinic Zr02 are characterized by the highest properties: after .firing at 1 580 ~C open porosity of 14. 3% - 14. 8%, apparent density of 4. 67 -4. 69 g · cm^-5, cold crushing strength of 62 - 68 MPa, thermal shock resistance ( 1 300℃←→air) of 15 thermal cycles, linear growth of 0. 2%. The manufacturing technology of powders mix-ture for ramming mix based on the new fused material .from ZrO2 stabilized by the combined additive is developed and its production is mastered. From this mixture the large-size, shaped products on the phosphate bond are made at one carbon black production plant, which are installed in the combustion chamber of the carbon black production reactor. 展开更多
关键词 fused stabilized zirconia combined additives calcia and magnesia ramming mix carbon black production reactor
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Research on Direct Torque Control System Based on Induction Motor
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作者 康劲松 陶生桂 毛明平 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期157-162,共6页
The mathematic model of direct torque control (DTC) was deduced. Two simulating models based on the MATLAB & SIMULINK were established. The emphasis is focused on study of the performance difference of the DTC sys... The mathematic model of direct torque control (DTC) was deduced. Two simulating models based on the MATLAB & SIMULINK were established. The emphasis is focused on study of the performance difference of the DTC system with stator flux hexagon and circle trajectories. The simulation waveforms of flux, torque and current characters with two flux trajectories were given. Experiments were carried out in an AC drive system based on induction motor and two-level inverter. A dual-CPU structure was used and the communication with two CPUs was obtained by a dual-port RAM in this system. 展开更多
关键词 direct torque control (DTC) flux trajectory flux observing model dual-port RAM
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Effect of Al Addition on Properties of Al_2O_3-SiC-C Dry Ramming Mixes for BF Trough
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作者 WANG Zhanmin WANG Qiang CAO Xiying 《China's Refractories》 CAS 2008年第3期1-5,共5页
Aluminium powders were introduced to Al2O3-SiC-C dry ramming mixes in order to improve sintering properties and oxidation resistance according to their service conditions and installation methods. Properties such as b... Aluminium powders were introduced to Al2O3-SiC-C dry ramming mixes in order to improve sintering properties and oxidation resistance according to their service conditions and installation methods. Properties such as bulk density, porosity, modulus of rupture, crushing strength and hot modulus of rupture as a function of aluminium addition were investigated in the present work. The microstructure and thermodynamics for the heat treated specimens were also analyzed. The results show that as aluminium addition increasing, the bulk density of the specimen treated at 220℃ tends to decrease and the apparent porosity increases, the strength of the specimens treated at 1100℃ and 1450℃ increases markedly, the bulk density tends to increase, apparent porosity and linear shrinkage decrease. The HMOR at 1400℃ is enhanced from 1.0 MPa to 3.5 MPa with 3% aluminium. Aluminium is served as sintering agent and anti-oxidant and it will react with CO and CO2 forming Al2O3 , which is helpful to enhance the strength, densify the structure and improve the overall properties. 展开更多
关键词 Al2O3 - SiC - C Dry ramming mixes BF Trough Oxidation resistance
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Modern Spontaneous Evolution and Research Value of Construction System of Tibetan Dwellings in Aba County: A Case Study of Tieqiong Village in Waerma Town
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作者 CAO Yong 《Journal of Landscape Research》 2017年第3期94-100,共7页
Based on the field survey of dwellings in Tieqiong Village of Waerma Town in Aba County, northwest Tibetan area of Sichuan Province, this paper firstly introduced main characteristics of the construction system in the... Based on the field survey of dwellings in Tieqiong Village of Waerma Town in Aba County, northwest Tibetan area of Sichuan Province, this paper firstly introduced main characteristics of the construction system in the structure, materials and structural system, and analyzed changes in construction practices of various dwellings from traditional to modern time. Finally, it summarized characteristics of spontaneous evolution and research value of the construction system of dwellings in the northwest Tibetan area of Sichuan Province, with rammed earth wooden dwellings in upper and middle Aba areas as representatives. 展开更多
关键词 TIBETAN DWELLINGS in Aba COUNTY Rammed earth buildings Construction system MODERN EVOLUTION
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Carbon Ramming Materials for Blast Furnace Construction
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作者 Wang jing Yu Lingyan 《China's Refractories》 CAS 2013年第4期39-41,共3页
1 Scope This standard specifies the definition, classifica- tion, technical requirements, test methods, quality ap- praisal procedure, packing, marking, transportation, stroage and quality certificate of carbon rammi... 1 Scope This standard specifies the definition, classifica- tion, technical requirements, test methods, quality ap- praisal procedure, packing, marking, transportation, stroage and quality certificate of carbon ramming mate- rials for blast furnace construction. This standard is applicable to carbon ramming materials for construction in leveling layer of blast furnace bottom, ramming layer upper or lower the cen- tral line of water cooling pipes, joints between carbon bricks, or joints between carbon bricks and cooling equipment. 展开更多
关键词 TEST Carbon ramming Materials for Blast Furnace Construction
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A DYNAMIC ECG MONITORING AND RECORDING SYSTEM
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作者 Lijun Tian, Zongzhan Du, Dongqing Wang(Department of Electrical PowerShandong Polytechnic University,Jinan, 250014,China)Aili Wang(Shandong Institute of Traditional Chinese Medicine,Jinan, 250014,China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1994年第1期38-46,共9页
This peper proposes a new type of dynamic ECG (Holier) monitoring andrecording system based on technology or computer controlling and high storage capacitydynamic RAM (DRAM). The system realizes the monitoring and rec... This peper proposes a new type of dynamic ECG (Holier) monitoring andrecording system based on technology or computer controlling and high storage capacitydynamic RAM (DRAM). The system realizes the monitoring and recording ECG signalscontinuously up to 24 hours with the double error criterion ECG data compression algorithm or time error and amplitude error[1], adaptive algorithm for detecting andanalysing the oRS complexes[2] and the technology of high storage capacity DRAM. Itsadvantages are high storage Capacity (4MB), low power dissipation (less titan 30mA). 展开更多
关键词 MONITORING and RECORDING high storage capacity DYNAMIC RAM DATACOMPRESSION detecting and analysing QRS SINGLE-CHIP microcomputer.
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The Automatic Control System For High-speed Material Hoist
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作者 Sun,Wenqian Wang,Bo 《微计算机信息》 2004年第3期12-13,共2页
This paper introduces the principle, software and hardware structure of automatic control system for high-speed material hoist, and analysis feature of the
关键词 EEPROM ROM RAM 存储器 计算机
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面向高速公路服务区自洽能源系统的RAMS评价方法
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作者 李艳波 汪静远 +3 位作者 陈圆媛 程绍峰 吕浩楠 陈俊硕 《吉林大学学报(工学版)》 北大核心 2025年第7期2243-2250,共8页
针对如何科学评价高速公路服务区自洽能源系统的弹性和能效这一难题,本文提出了一种基于传统RAMS评价方法的高速公路服务区自洽能源系统的评价方法。首先,分析了服务区自洽能源系统的结构及特点,考虑可靠性、可用性、可维修性和安全性4... 针对如何科学评价高速公路服务区自洽能源系统的弹性和能效这一难题,本文提出了一种基于传统RAMS评价方法的高速公路服务区自洽能源系统的评价方法。首先,分析了服务区自洽能源系统的结构及特点,考虑可靠性、可用性、可维修性和安全性4个方面的影响因素,建立了面向服务区自洽能源系统的评价模型,并设计评价策略。其次,基于熵权-TOPSIS法确定各项指标的权重,基于改进AHP-VIKOR法确定系统各项属性的权重,建立新型多准则综合评价体系。最后,选取某服务区作为算例进行对比分析,验证了本文方法在评价自洽能源系统方面的正确性与合理性。 展开更多
关键词 交通运输系统工程 自洽能源系统 高速服务区 多准则评价体系 RAMS评价
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