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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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基于Mask R-CNN的电力关键设备运行状态检测
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作者 吕超 杨德宇 +1 位作者 刘文杰 张克胜 《电子设计工程》 2024年第2期107-110,115,共5页
为判断电力关键设备两端负载电压与干路总电压之间的数值关系,提出基于Mask R-CNN的电力关键设备运行状态检测方法。在Mask R-CNN网络结构中,判断电量信号的时域范围与频域范围。然后根据负荷阻抗特征计算交流参数的取值结果,再联合已... 为判断电力关键设备两端负载电压与干路总电压之间的数值关系,提出基于Mask R-CNN的电力关键设备运行状态检测方法。在Mask R-CNN网络结构中,判断电量信号的时域范围与频域范围。然后根据负荷阻抗特征计算交流参数的取值结果,再联合已获取的电信号参量,求解连续相关函数,从而检测电力关键设备运行状态。实验过程中,设备两端负载电压、内阻消耗电压之和与干路总电压之间的差值未超过1.5 V,说明该方法能够证明电力关键设备两端负载电压、内阻消耗电压之和等于干路总电压数值的猜想成立,可以根据该验证检测电力关键设备运行状态是否正常。 展开更多
关键词 Mask R-CNN模型 电力设备 运行状态 负荷阻抗 交流参数 负载电压
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Running States of China's Iron & Steel,Nonferrous,and Building Materials Industries in 2012
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《China's Refractories》 CAS 2013年第1期11-11,共1页
Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY... Iron & Steel Industry China's outputs of crude steel, steel products, coke and ferrous alloys in 2012 were 716.54 million tons (up 3.1% YOY), 051.86 million tons (up 7.7% YOY), 443.23 million tons (up 5.2% YOY) and 31.29 million tons (up 15% YOY), 展开更多
关键词 running states of China’s Iron Steel Nonferrous and Building Materials Industries in 2012
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Running State of China's Building Materials Industry in 2013
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《China's Refractories》 CAS 2014年第1期42-42,共1页
In 2013, China's outputs of cement and flat glass were 2. 414 billion tons and 778.98 million weight cases, increasing by 9.6% and 11.2% YOY, respectively.
关键词 running state of China’s Building Materials Industry in 2013
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Effect of Run - in Ratios on the Mechanical Properties of Two - Guide Bars Warp - Knitted Fabrics 被引量:1
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作者 陈雨梁 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期87-89,共3页
Warp knitting technology gets rapid development at present and becomes one of the most important parts of the textiles.But it is less known how the parameters of warp knitting technology affect the mechanical properti... Warp knitting technology gets rapid development at present and becomes one of the most important parts of the textiles.But it is less known how the parameters of warp knitting technology affect the mechanical properties of warp-knitted fabrics.This paper presents discuss a research on the relationships between run-in ratio and mechanical properties of the two-bar warp-knittedfabrics through the measurement and analysis of the mechanical properties of various samples with different run-in ratios.The optimal run一in ratios for the reasonable mechanical properties are obtained from above dis- 展开更多
关键词 run - in ratios MECHANICAL property TWO - bar WARP - KNITTED fabric .
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Effect of varying normal stress on stability and dynamic motion of a spring-slider system with rate- and state-dependent friction 被引量:2
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作者 Changrong He Teng-fong Wong 《Earthquake Science》 2014年第6期577-587,共11页
Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable... Incorporating rate and state friction laws, stability of linearly stable (i.e., with stiffness greater than the critical value) spring-slider systems subjected to triggering perturbations was analyzed under variable normal stress condition, and comparison was made between our results and that of fixed normal stress cases revealed in previous studies. For systems associated with the slip law, the critical mag- nitude of rate steps for triggering unstable slips are found to have a similar pattern to the fixed normal stress case, and the critical velocity steps scale with a/(b - a) when k = kcr for both cases. The rate-step boundaries for the variable normal stress cases are revealed to be lower than the fixed normal stress case by 7 %-16 % for a relatively large ct = 0.56 with (b - a)/a ranging from 0.25 to 1, indicating easier triggering under the variable normal stress condition with rate steps. The difference between fixed and variable normal stress cases decreases when the α value is smaller. In the same slip- law-type systems, critical displacements to trigger instability are revealed to be little affected by the variable normal stress condition. When k 〉 kcr(V,), a spring-slider system with the slowness law is much more stable than with the slip law,suggesting that the slowness law fits experimental data better when a single state variable is adopted. In stick-slip motions, the variable normal stress case has larger stress drops than the constant normal stress case. The variable normal stress has little effect on the range of slip velocity in systems associated with the slowness law, whereas systems associated with the slip law have a slowest slip velocity immensely smaller than the fixed normal stress case, by ~ 10 orders of magnitude. 展开更多
关键词 Rate and state friction - Stability Variablenormal stress Stick-slip motion
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Solid-state synthesis of Sr-and Co-doped LaMnO_3 perovskites 被引量:1
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作者 马文会 谢刚 +1 位作者 陈书荣 崔衡 《中国有色金属学会会刊:英文版》 CSCD 2001年第6期904-907,共4页
The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and parti... The synthesis process for La 1- x Sr x Mn 1- y Co y O 3- δ ( x = 0.2, 0.3; y = 0.2, 0.8, designated as LSMC below) perovskite oxides prepared by solid state reaction was investigated using DSC/TG, XRD, EPMA and particle size analysis methods. It was found that LSMCs were all of single phase and the synthesis process might be divided into three stages: the decomposition of reactants, the formation of LaMn(Co)O 3 based oxides, and the formation of LSMC solid solution. Typical average and the peak value of particle size, and the specific surface area are 14.65?μm, 16.4?μm and 1.38?m 2/mL, respectively, for mixed reactants and are 23.81?μm, 32.11?μm and 0.5?m 2/mL, respectively, for powder synthesized at 1?200?℃ for 8?h in air. 展开更多
关键词 solid state reaction synthesis La 1- x Sr x Mn 1- y Co y O 3- δ perovskite intermediate temperature SOFCs
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Elaborately tuning the electronic structure of single-atom nickel sites using nickel nanoparticles to markedly enhance the electrochemical reduction of nitrate into ammonia 被引量:1
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作者 Zichao Xi Jiaqian Wang +4 位作者 Baocang Liu Xuan Xu Peng Jing Rui Gao Jun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期32-42,I0003,共12页
The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally ... The electrochemical reduction of nitrate to ammonia(NH3) can be used to recycle nitrogen and offers a decarbonized route for sustainable NH3production,but requires efficient electrocatalysts.Herein,we have rationally designed and fabricated a novel self-supported electrocatalyst comprised of Ni nanoparticles(NiNPs) embedded in Ni single atoms(NiSAs) anchored to nitrogen-doped carbon nanotubes grown on carbon cloth(NiNPs@NiSAs-NCNTs/CC) used for an efficient nitrate reduction reaction(NO3-RR) to produce NH_(3).The electrocatalyst can attain a maximum NH3yield rate of 27.67±1.16 mgNH3h^(-1)cm^(-2)at-1.4 V vs.reversible hydrogen electrode(RHE) and nearly 100% Faradic efficiency in the range of-1.2--1.4 V vs.RHE in a neutral medium,outperforming the previously reported Ni-based catalysts.Our experimental analysis and theoretical calculations have demonstrated that the moderate electrondeficient state of NiSAsregulated by NiNPsnot only facilitates the enrichment of NO_(3)^(-),but also benefits the formation of NO3*and decrease in the energy barrier of the rate-limiting step,thus resulting in the enhanced NO3-RR performance. 展开更多
关键词 Nitratereductionreaction Moderateelectron-deficient state Self-supported ELECTROCATALYST Enrichmentof NO_(3)^(-) Theoreticalcalculations
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Modeling of Solid-state Polycondensation of Poly (ethylene terephthalate)
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作者 邓德纯 王燕萍 +2 位作者 蒋歧康 唐志廉 黄南薰 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期30-33,共4页
A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considere... A mathematical model has been developed to handle the reactions in Poly(ethylene terephthalate) (PET) undergoing polycondensation reactions in the solid state. The effect of temperature on chain mobility was considered to estimate the rate constants of chemical reactions. The polymer crystalline fraction is modeled as containing only repeat units, thus concentrating end groups and conden-sates in the amorphous fraction. This model is compared with PET reaction data with good results. 展开更多
关键词 SOLID - state POLYMERIZATION PET POLYMER REACTION engineering.
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Equation of State of Nuclear Matter in Chiral σ-ω Model
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作者 CHENWei DONGDong-Qiao +2 位作者 WENDe-Hua LIUGuo-Tao LIULiang-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期925-928,共4页
The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω mode... The equation of state of nuclear matter is studied in the 1-loop approximation of chiral linear σ-ω model.By introducing the density-dependent coupling constants, the problem of tachyon pole in the chiral σ-ω model is resolved.The 1-loop contributions ofσ and π mesons to the nucleon's binding energy are included, while the empirical properties of nuclear matter such as saturation density, binding energy, and incompressibility are well reproduced. 展开更多
关键词 equation of state chiral σ-ω model
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Materials Design on the Origin of Gap States in a High-κ/GaAs Interface
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作者 Weichao Wang Cheng Gong +3 位作者 Ka Xiong Santosh K.C. Robert M.Wallace Kyeongjae Cho 《Engineering》 SCIE EI 2015年第3期372-377,共6页
Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current... Given the demand for constantly scaling micro- electronic devices to ever smaller dimensions, a SiO2 gate dielectric was substituted with a higher dielectric-constant material, Hf(Zr)O2, in order to minimize current leakage through dielectric thin film. However, upon interfacing with high dielectric constant (high-κ) dielectrics, the electron mobility in the conventional Si channel degrades due to Coulomb scattering, surface-roughness scattering, remotephonon scattering, and dielectric-charge trapping.Ⅲ-Ⅴ and Ge are two promising candidates with superior mobility over Si. Nevertheless, Hf(Zr)O2/Ⅲ-Ⅴ(Ge) has much more complicated interface bonding than Si-based interfaces. Successful fabrication of a high-quality device critically depends on understanding and engineering the bonding configurations at Hf(Zr)O2/Ⅲ-Ⅴ(Ge) interfaces for the optimal design of device interfaces. Thus, an accurate atomic insight into the interface bonding and mechanism of interface gap states formation becomes essential. Here, we utilize first- principle calculations to investigate the interface between HfO2 and GaAs. Our study shows that As--As dimer bonding, Ga partial oxidation (between 3+ and 1+) and Ga- dangling bonds constitute the major contributions to gap states. These findings provide insightful guidance for optimum interface passivation. 展开更多
关键词 high-mobility device high-κ/Ⅲ- interface interfacial gap states first-principle calculations
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The “Non-Locality” of Entangled States Is Seeming Phenomenon
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作者 Marat Guryev 《Journal of Applied Mathematics and Physics》 2017年第9期1791-1796,共6页
EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation meth... EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation methods that were available at that time. However, we can easily explain this observable NL as a trivial result of conservation laws (CL) within modern quantum mechanics (MQM). But application of CL requires materialistic descriptions of reality in a micro world in contrast to so-called quantum measurement theory (QMT), which was created mainly in the times of EPR and is widely accepted until now. We have to use a materialistic description, just as many physicists who actually work with high precision do by default. In this article, practical examples are given for real, precise measurements of wave functions of molecules and crystals, which, of course, were not known to EPR and were not noticed by their followers. We should acknowledge that QMT is merely an unneeded complication of simple relations of MQM. NL is the seeming result of these complications. 展开更多
关键词 NON-LOCALITY ENTANGLED states Quantum MEASUREMENT Theory EPR Electron DIFFRACTION Neutron DIFFRACTION y - RAY DIFFRACTION MEASUREMENT of Wave Function
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Problems and Countermeasures of Taihu Port Farm in Jingzhou City after Function Reform of Running the Society
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作者 Hefan XU Jun ZHENG Jiafeng YU 《Asian Agricultural Research》 2019年第8期1-4,共4页
Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementi... Deepening function reform of running the society of state-owned farm is an important strategic plan made by the Party Central Committee and the State Council,and is also ' hard bone' bitten by fully implementing the strategy of rural revitalization and promoting the modernization of agriculture and countryside. In this paper,the problems of Taihu Port Farm in Jingzhou City after function reform of running the society are systematically and comprehensively analyzed via field research,and corresponding countermeasures are proposed. The research could provide beneficial reference and experience reference for deepening function reform of running the society of current state-owned farm. 展开更多
关键词 Function reform of running the SOCIETY of state-OWNED FARM Agricultural MODERNIZATION Rural REVITALIZATION Taihu PORT FARM
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基于CNN-LSTM的轨道车辆轮对运行状态识别方法研究 被引量:1
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作者 雍心剑 陆正刚 《机电工程技术》 2023年第5期19-24,76,共7页
轨道车辆的轮对运行实时状态是评价车辆运行安全性及轮对导向控制的关键信息,针对轨道车辆在运行过程中轮对横移、摇头角实时状态直接测量成本高、难度大等问题,提出了一种基于卷积神经网络(CNN)内嵌长短记忆(LSTM)网络的轮对运动状态... 轨道车辆的轮对运行实时状态是评价车辆运行安全性及轮对导向控制的关键信息,针对轨道车辆在运行过程中轮对横移、摇头角实时状态直接测量成本高、难度大等问题,提出了一种基于卷积神经网络(CNN)内嵌长短记忆(LSTM)网络的轮对运动状态识别及预测方法。以轮对横向加速度、轮对摇头角加速度、一系悬挂位移量等易测信号构成特征集,通过CNN对时序信号进行多维度空间特征提取并输入到LSTM中捕获时序特征,最后通过全连接层输出轮对横移及摇头角的预测值,结合车辆运行的实际工况特点,对预测模型的泛化性及鲁棒性进行检验。仿真结果表明:相较于传统的单LSTM识别模型,CNN-LSTM模型能有效降低轮对运动状态的识别误差,且在不同运行工况以及车辆物理参数变化的情况下,该模型具有高鲁棒性,能够保持较高的预测精度。 展开更多
关键词 轨道车辆 轮对运动状态 状态识别 卷积神经网络 长短时记忆网络
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State of Country Report——Foreign Trade 2009-2010
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作者 Nie Ting 《China Textile》 2009年第12期22-25,共4页
Facing economic crisis in the world 2009, international market demands suffered a serious recession, also China's foreign trade has encountered unprecedented difficulties. In front of this, Chinese Government take... Facing economic crisis in the world 2009, international market demands suffered a serious recession, also China's foreign trade has encountered unprecedented difficulties. In front of this, Chinese Government takes series of adjustment timely to get over this rough time. So how is China's foreign trade in 2009, and where it will go in 2010, let's have a look at this… 展开更多
关键词 Foreign Trade 2009-2010 state of Country Report
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Unveiling the planar deformation mechanisms for improved formability in pre-twinned AZ31 Mg alloy sheet at warm temperature
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作者 Xiaohuan Pan Lifei Wang +8 位作者 Pengbin Lu Hua Zhang Guangsheng Huang Liuwei Zheng Bin Xing Weili Cheng Hongxia Wang Wei Liang Kwang Seon Shin 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4659-4678,共20页
To investigate the role of pre-twins in Mg alloy sheets during warm planar deformation,the stretch forming is conducted at 200℃.Results suggest the formability of the pre-twinned AZ31 Mg alloy sheet is enhanced to 11... To investigate the role of pre-twins in Mg alloy sheets during warm planar deformation,the stretch forming is conducted at 200℃.Results suggest the formability of the pre-twinned AZ31 Mg alloy sheet is enhanced to 11.30 mm.The mechanisms for the improved formability and the deformation behaviors during the planar stretch forming are systematically investigated based on the planar stress states.The Schmid factor for deformation mechanisms are calculated,the results reveal that planar stress states extremely affect the Schmid factor for{10-12}twinning.The detwinning is activated and the prismatic slip is enhanced in the pre-twinned sheet,especially under the planar extension stress state in the outer region.Consequently,the thickness-direction strain is accommodated better.The dynamic recrystallization(DRX)type is continuous DRX(CDRX)regardless of the planar stress state.However,the CDRX degree is greater under the planar extension stress state.Some twin lattices deviate from the perfect{10-12}twinning relation due to the planar compression stress state and the CDRX.The basal texture is weakened when the planar stress state tends to change the texture components. 展开更多
关键词 AZ31 Mg alloy sheet Planar stretch forming Planar stress states Continuous dynamic recrystallization {10-12}tensile twinning
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基于双重约束的并网逆变器电流自动化控制方法研究
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作者 陈志刚 高冰 +1 位作者 李滨 杨晓磊 《自动化与仪表》 2024年第2期30-34,共5页
为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函... 为降低并网逆变器逆变的并网电流畸变率,提出基于双重约束的并网逆变器电流自动化控制方法。以典型的三相LCL并网逆变器为例,分析其运行状态;并确定并网逆变器在进行逆变转换时,谐波对于逆变器并网电流的影响,计算并网逆变器环路增益函数;采用输出电流直接前馈的改进阻尼控制方法实现电流自动化控制,并引入全局-局部稳定双重约束原则,确定最佳的谐振抑制参数,提升电流的控制效果。测试结果显示,该方法的并网逆变器的电流畸变率均低于5%,电流跳变过程中,可在0.2 s内有效控制跳变电流结果。 展开更多
关键词 双重约束 并网逆变器 自动化控制 谐振抑制参数 增益函数 运行状态
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抗战时期宜红茶复兴计划与国营体系的建立
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作者 李超 许胜男 《农业考古》 北大核心 2024年第2期33-41,共9页
晚清以来,在国际市场需求的带动和自身发展优势的基础上,宜红茶贸易兴起,区域茶业逐渐兴盛,并形成了“宜红茶”品牌。抗战时期,在国际国内局势和“中国茶业复兴计划”的影响下,“宜红复兴计划”被提出。中国茶叶公司、湖北省平价物品供... 晚清以来,在国际市场需求的带动和自身发展优势的基础上,宜红茶贸易兴起,区域茶业逐渐兴盛,并形成了“宜红茶”品牌。抗战时期,在国际国内局势和“中国茶业复兴计划”的影响下,“宜红复兴计划”被提出。中国茶叶公司、湖北省平价物品供应处茶叶部先后在宜红茶区投资设厂,推动了宜红茶区国营茶厂的建立与国营体系的发展,体现了传统商品经济在近代全球化趋势中的生存境遇与抉择,奠定了区域茶业社会经济的历史格局。 展开更多
关键词 宜红茶 国营茶厂 抗战时期
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基于转子铜耗的异步机运行状态分类
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作者 程小华 《防爆电机》 2024年第4期1-3,共3页
提出一个关于异步机运行状态的新的分类方法:转子铜耗法。按此法,异步机运行状态可分为两个:差能态、和能态。差能态包含电动、发电两个态;和能态对应电制态。转子铜耗分类法对学习和巩固异步机制动知识点尤其有帮助。
关键词 异步机 运行状态分类 转子铜耗 差能态 和能态 转差率 电制 电动 发电
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内燃机缸套-活塞环磨合研究概述 被引量:6
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作者 马晨波 朱华 《润滑与密封》 CAS CSCD 北大核心 2008年第11期102-106,共5页
在对缸套-活塞环磨合过程的数学模型、影响因素及磨合状态的评定参数3个方面的国内外研究现状进行概述的基础上,对其中存在的一些问题进行了探讨和分析,并对缸套-活塞环磨合过程的进一步研究提出如下建议:微凸体承载方程中考虑磨合的动... 在对缸套-活塞环磨合过程的数学模型、影响因素及磨合状态的评定参数3个方面的国内外研究现状进行概述的基础上,对其中存在的一些问题进行了探讨和分析,并对缸套-活塞环磨合过程的进一步研究提出如下建议:微凸体承载方程中考虑磨合的动态性;研制模拟缸套-活塞环工况的磨合磨损试验机,定量研究磨合中的影响因素;研究缸套-活塞环磨合状态评定参量到达稳定状态时间不同的影响因素。 展开更多
关键词 缸套 活塞环 磨合
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