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基于S7-300PLC的净水厂V型滤池控制系统设计思路探究
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作者 姚家泰 《中国设备工程》 2024年第S02期133-135,共3页
净水厂是城市供水的主要来源,净水厂出厂水质的安全可靠是确保安全饮用水的首要任务。滤池是净水厂工艺流程中水处理关键环节,对出厂水质产生直接影响。随着科技的发展和进步,实现净水厂滤池自动化高效运行,本文围绕基于S7-300 PLC的净... 净水厂是城市供水的主要来源,净水厂出厂水质的安全可靠是确保安全饮用水的首要任务。滤池是净水厂工艺流程中水处理关键环节,对出厂水质产生直接影响。随着科技的发展和进步,实现净水厂滤池自动化高效运行,本文围绕基于S7-300 PLC的净水厂V型滤池控制系统设计展开一系列的探讨,分析研究了净水厂V型滤池在正常过滤过程和反冲洗功能的难点和解决方法,并实现净水厂V型滤池在正常过滤过程和反冲洗功能控制系统精确控制,经过三亚市某水厂的实际运行检验,系统可靠稳定,同时使得净水厂出厂水质符合生活饮用水标准,希望能给净水厂V型滤池控制系统设计上带来一些帮助。 展开更多
关键词 净水厂 v型滤池 s7-300 PLC 控制系统
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Effects of natural-cerebrolysin-containing serum on neurotoxicity and synaptogenesis in amyloid-beta 1-40-induced Alzheimer's disease in vitro models 被引量:1
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作者 Yinghong Li Zhengzhi Wu +3 位作者 Andrew C. J. HuangO Ming Li XiaoLi Zhang Jiguo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期85-91,共7页
BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, an... BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression. 展开更多
关键词 natural-cerebrolysin Alzheimer's disease in vitro model NEUROTOXICITY neuroprotective effect amyloid beta protein 1-40
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UWB Channel Modeling Improvement in Indoor Line-of-Sight (LOS) Environments
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作者 Vahid Tabataba Vakili Dariush Abbasi-Moghadam Mostafa Yahyaabadi 《International Journal of Communications, Network and System Sciences》 2010年第11期870-876,共7页
Channel measurement and modeling is an important issue when designing ultra wideband (UWB) communication systems. A Precise model of the channel response is inevitable for designing an ultra wideband telecommunication... Channel measurement and modeling is an important issue when designing ultra wideband (UWB) communication systems. A Precise model of the channel response is inevitable for designing an ultra wideband telecommunication system. In this article signal propagation in indoor environment and LOS condition is evaluated and the appropriate model of this scenario is presented. Parameters such as the power delay profile, mean excess delay, delay spread, “NP10dB” are analyzed and simulated. Based on analysis results, the proposed model is presented. This model is based on Two-cluster approach but its average power delay profile is described with power function and cluster time of arrival is modeled by the modified exponential distribution. Finally UWB channel parameters of proposed model, Saleh and Valenzuela (S-V) and Two-cluster models are compared. Measurement and simulation results show that considerable improvement for mean excess delay, delay spread and “NP10dB” of proposed model comparing with S-V and Two-cluster model, this means the channel is better described, which mean the channel is described more precisely. 展开更多
关键词 Channel modeling s-v model Power DELAY PROFILE Ultra WIDEBAND
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基于v-支持向量回归的T-S模糊模型辨识 被引量:8
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作者 李益国 沈炯 《中国电机工程学报》 EI CSCD 北大核心 2006年第18期148-153,共6页
结论参数对T-S模糊模型的泛化能力有重要影响。该文引入v-支持向量回归机(v-SVRM),把T-S模型结论参数的辨识问题转化为一个约束优化问题,并推导了新的迭代求解算法。该方法通过一个参数v控制支持向量的数目和落在ε不灵敏带外样本点的数... 结论参数对T-S模糊模型的泛化能力有重要影响。该文引入v-支持向量回归机(v-SVRM),把T-S模型结论参数的辨识问题转化为一个约束优化问题,并推导了新的迭代求解算法。该方法通过一个参数v控制支持向量的数目和落在ε不灵敏带外样本点的数目,并自动计算合适的ε。针对典型负荷被控对象的仿真结果表明:该方法比通常采用最小二乘法进行结论参数辨识的方法具有更好的泛化能力;此外,由于采用了ε不灵敏损失函数,该方法具有更好的噪声适应能力。 展开更多
关键词 v-支持向量回归 T-s模糊模型 泛化性能 ε不灵敏损失函数 负荷系统
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基于S7-200和V80伺服定位系统设计 被引量:5
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作者 董明 邵伟 陆蔺辉 《制造业自动化》 北大核心 2014年第14期105-107,116,共4页
介绍了某厚度测量装置中设计的一套精密伺服定位控制系统,该定位系统设计采用了S7-200系列PLC和V80伺服驱动器。详细阐述了测量原理、伺服定位控制系统结构、控制策略及控制流程。通过对伺服驱动器、运动包络参数配置和逻辑流程设计,实... 介绍了某厚度测量装置中设计的一套精密伺服定位控制系统,该定位系统设计采用了S7-200系列PLC和V80伺服驱动器。详细阐述了测量原理、伺服定位控制系统结构、控制策略及控制流程。通过对伺服驱动器、运动包络参数配置和逻辑流程设计,实现了对被控对象的精密定位控制、速度控制、方向控制。最后还介绍了伺服定位系统定位误差消除方法。该伺服定位系统定位运行平稳,定位精度可达到1微米。 展开更多
关键词 s7-200 v80 伺服 定位
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含硫钾盐对V2O5-WO3/TiO2催化剂上SO3生成特性的影响 被引量:3
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作者 肖海平 豆朝宗 +3 位作者 袁宗海 李建 葛金林 吕洪坤 《动力工程学报》 CAS CSCD 北大核心 2020年第2期145-151,共7页
采用湿式浸渍法制备含硫钾盐催化剂,研究含硫钾盐对SCR催化剂上SO3生成特性的影响,并采用不同分析技术对SCR催化剂特性进行表征。结果表明:K2S2O7和K2SO4能明显提高SO3生成率;随着含硫钾盐质量分数的增加,SO3生成率提高;在410℃下3.6%K2... 采用湿式浸渍法制备含硫钾盐催化剂,研究含硫钾盐对SCR催化剂上SO3生成特性的影响,并采用不同分析技术对SCR催化剂特性进行表征。结果表明:K2S2O7和K2SO4能明显提高SO3生成率;随着含硫钾盐质量分数的增加,SO3生成率提高;在410℃下3.6%K2S2O7-SCR催化剂的SO3生成率达到最大;SO2质量浓度为3000 mg/m^3时,3.6%K2S2O7-SCR催化剂的SO3质量浓度最大;含硫钾盐存在时,SCR催化剂的还原性能下降,比表面积减小;含硫钾盐存在时,SCR催化剂表面化学吸附氧质量分数和V^5+质量分数均增大,V^5+=O键的振动峰强度明显增强,SCR催化剂的氧化能力增强。 展开更多
关键词 sO3生成 v2O5-WO3/TIO2 含硫钾盐 s2O7^2- sO^2-4
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新型钒系固体超强酸S_2O_8^(2-)/V_2O_5催化剂的制备研究
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作者 吴思展 徐彬 +1 位作者 陈良为 舒华 《广州化工》 CAS 2011年第15期73-75,共3页
以NH4VO3为原料,(NH4)2S2O8为浸渍液,添加一定量Fe2O3,用沉淀-浸渍法制备出新型S2O82-/V2O5-Fe2O3固体超强酸催化剂。以合成乙酸苄酯作为探针反应,考察不同制备条件下超强酸的催化活性。研究发现,最优条件为:V2O5与Fe2O3的摩尔比为n(V2... 以NH4VO3为原料,(NH4)2S2O8为浸渍液,添加一定量Fe2O3,用沉淀-浸渍法制备出新型S2O82-/V2O5-Fe2O3固体超强酸催化剂。以合成乙酸苄酯作为探针反应,考察不同制备条件下超强酸的催化活性。研究发现,最优条件为:V2O5与Fe2O3的摩尔比为n(V2O5)∶n(Fe2O3)=1.0∶1.0,浸渍液浓度为1.5 mol/L,焙烧温度350℃,焙烧时间3 h效果最佳,催化剂的活性最好。 展开更多
关键词 固体超强酸 s2O28-/v2O5-Fe2O3 催化剂 制备
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浅谈S7-1500与SINAMICS V90通过PROFINET实现位置定位控制 被引量:4
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作者 吴金标 肖锡清 姜鹏 《中国高新技术企业》 2016年第32期62-63,共2页
文章介绍了S7-1500 PLC与SINAMICS V90伺服系统如何通过PROFINET通讯实现位置闭环控制,并分析了在S7-1500中以工艺对象的方式来实现定位控制功能的具体方法,对S7-1500相关模块的组态、工艺对象的组态、V90的相关参数设置以及SINAMICS V-... 文章介绍了S7-1500 PLC与SINAMICS V90伺服系统如何通过PROFINET通讯实现位置闭环控制,并分析了在S7-1500中以工艺对象的方式来实现定位控制功能的具体方法,对S7-1500相关模块的组态、工艺对象的组态、V90的相关参数设置以及SINAMICS V-ASSISTANT调试软件进行了介绍。 展开更多
关键词 s7-1500 sINAMICs v90 PROFINET通讯 位置闭环控制 位置定位控制
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Dynamic changes of microbial community diversity in a photohydrogen producing reactor monitored by PCR-DGGE 被引量:12
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作者 YING Yanling LV Zhenmei +1 位作者 MIN Hang CHENG Jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第9期1118-1125,共8页
A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extract... A PCR-DGGE (denaturing gradient gel electrophoresis of polymerase chain reaction) protocol was used for monitoring the dynamic changes in the microbial population during photohydrogen production. Total DNA was extracted directly from the mixed bacterial community in the reactor and subjected to PCR with V3-16S rDNA and pufM gene primers, and the amplifications were then analyzed by DGGE. The DGGE patterns demonstrated the dynamics of community structure and the shift of microbial diversity, which correspond... 展开更多
关键词 PCR-DGGE v3-16s rDNA region pufM gene photohydrogen producing reactor
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The relationship between international crude oil prices and China's refined oil prices based on a structural VAR model 被引量:4
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作者 Song Han Bao-Sheng Zhang +1 位作者 Xu Tang Ke-Qiang Guo 《Petroleum Science》 SCIE CAS CSCD 2017年第1期228-235,共8页
With the frequent fluctuations of international crude oil prices and China's increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domesti... With the frequent fluctuations of international crude oil prices and China's increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domestic refined oil price. This paper aims to investigate the transmission and feedback mechanism between international crude oil prices and China's refined oil prices for the time span from January 2011 to November 2015 by using the Granger causality test, vector autoregression model, impulse response function and variance decomposition methods. It is demonstrated that variation of international crude oil prices can cause China domestic refined oil price to change with a weak feedback effect. Moreover, international crude oil prices and China domestic refined oil prices are affected by their lag terms in positive and negative directions in different degrees. Besides, an international crude oil price shock has a signif- icant positive impact on domestic refined oil prices while the impulse response of the international crude oil price variable to the domestic refined oil price shock is negatively insignificant. Furthermore, international crude oil prices and domestic refined oil prices have strong historical inheri- tance. According to the variance decomposition analysis, the international crude oil price is significantly affected by its own disturbance influence, and a domestic refined oil price shock has a slight impact on international crude oil price changes. The domestic refined oil price variance is mainly caused by international crude oil price disturbance, while the domestic refined oil price is slightly affected by its own disturbance. Generally, domestic refined oil prices do not immediately respond to an international crude oil price change, that is, there is a time lag. 展开更多
关键词 International crude oil prices China's refinedoil prices vAR model Granger causality - Impulseresponse variance decomposition
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基于改进型不透水表面指数的城市V-I-S特征研究——以兰州市为例 被引量:4
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作者 王婷 武坚 +2 位作者 马选峰 王历明 钮立功 《甘肃科学学报》 2014年第4期61-65,共5页
为了更好的利用光谱指数特征对城市V-I-S地表覆被格局特征进行研究,在深入分析研究区基本组分地表覆被类型特征后,通过创建改进型归一化差值不透水表面指数(MNDISI),并结合改进型归一化差异水体指数(MNDWI)、土壤调节植被指数(SAVI),以... 为了更好的利用光谱指数特征对城市V-I-S地表覆被格局特征进行研究,在深入分析研究区基本组分地表覆被类型特征后,通过创建改进型归一化差值不透水表面指数(MNDISI),并结合改进型归一化差异水体指数(MNDWI)、土壤调节植被指数(SAVI),以及不同地表覆被类型在近红外和短波红外波段的平均反射率值等六组参数作为主要特征,基于Landsat TM影像,在面向对象的最邻近分类器中进行城市V-I-S基本组分地表覆被类型信息的提取与分类,精度评价得出生产者精度、用户精度、总体精度和Kappa系数分别达到92.5%、88.4%、87.5%和0.85以上.结果证明该方法实现了大范围区域城市V-I-S基本组分地表覆被类型信息和格局特征的自动准确提取. 展开更多
关键词 城市v—I—s地表覆被 LANDsAT TM影像 面向对象影像分析 改进型归一化差值不透水表 面指数(MNDIsI)
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Development of a Zebrafish Model for Rapid Drug Screening against Alzheimer's Disease 被引量:3
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作者 Wenhai Huang Chuansheng Li +3 位作者 Zhengrong Shen Xiaoyu Zhu Bo Xia Chunqi Li 《Journal of Pharmacy and Pharmacology》 2016年第4期162-173,共12页
Alzheimer's disease, the leading cause of dementia in the elderly, is a complex neurodegenerative disorder which leads to a progressive decline in cognitive functions. A rapid screening model is highly demanded for i... Alzheimer's disease, the leading cause of dementia in the elderly, is a complex neurodegenerative disorder which leads to a progressive decline in cognitive functions. A rapid screening model is highly demanded for identification and evaluation of novel anti-Alzheimer's disease drugs from a large numbers of compounds. Until now, numerous studies utilized zebrafish model for drug discovery. Since aluminum can induce a similar biological activity in zebrafish as in Alzheimer patients, in this study, we developed a novel animal model using 3 to 5 day post-fertilization larval zebrafish by optimizing the doses and duration of aluminum chloride exposure. Six anti-Alzheimer's disease drugs with a variety of mechanisms were tested to validate the newly developed zebrafish model. Importantly, Rivastigmine, ThT, Flurbiprofen and AM-117 could increase the value of Dyskinesia Recovery Rate by 53.4-64%, 169.4-200%, 54.5-96% and 70.9-121%, respectively. Rivastigmine, Memantine, ThT, Flurbiprofen, Rosiglitazone and AM-117 improved the value of Response Efficiency by 86.6-175.1%, 28.2-66.6%, 127.2-236.5%, 118.3-323.7%, 26.6-140.8% and 70.2-161.4%, respectively. Our results suggest that the zebrafish model developed in this study could be a useful tool for high throughput screening of potential novel anti-Alzheimer's disease leading compounds targeting acetylcholinesterase, N-methyl-D-aspartic acid receptor, γ-secretase, peroxisome proliferator-activated receptor-γand amyloid-β. 展开更多
关键词 Alzheimer's disease 3-5dpf Larvae screening platform zebrafish model.
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基于西门子S7-200 SMART的SINAMICS V90位置控制应用 被引量:6
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作者 翟雳 《数字技术与应用》 2020年第7期1-2,共2页
为了探究如何更方便、准确地实现位置控制,确保其位置控制的精度,本文探讨了基于西门子S7-200 SMART系列PLC和SINAMICS V90伺服系统的位置控制方法。通过介绍系统软硬件构成及其特点,详细论述了PLC系统通过外部脉冲位置控制模式控制伺... 为了探究如何更方便、准确地实现位置控制,确保其位置控制的精度,本文探讨了基于西门子S7-200 SMART系列PLC和SINAMICS V90伺服系统的位置控制方法。通过介绍系统软硬件构成及其特点,详细论述了PLC系统通过外部脉冲位置控制模式控制伺服电机,以实现相对运动的过程。 展开更多
关键词 s7-200 sMART sINAMICs v90 位置控制
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基于WINCCV7.0和S7-1500的锯切成套设备控制系统的设计 被引量:3
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作者 陆毅华 《机电工程技术》 2015年第4期16-20,共5页
传统铝铸造行业需要通过提高设备的自动化水平,以提高企业的竞争力。锯切成套设备是一套铝棒锯切的全自动化设备,能有效提高铝棒锯切的效率。主要介绍了基于WINCC V7.0和S7-1500的锯切成套设备控制系统的设计及其关键技术。以该控制系... 传统铝铸造行业需要通过提高设备的自动化水平,以提高企业的竞争力。锯切成套设备是一套铝棒锯切的全自动化设备,能有效提高铝棒锯切的效率。主要介绍了基于WINCC V7.0和S7-1500的锯切成套设备控制系统的设计及其关键技术。以该控制系统为核心的锯切成套控制系统在铝铸造企业的实际应用中取得了很好的效果。 展开更多
关键词 WINCC v7.0 s7-1500 锯切成套设备 OPC通信
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Simatic S7-1200和Sinamics V20在卷绕机上的应用 被引量:2
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作者 游辉胜 《电气技术》 2018年第10期85-87,91,共4页
本文主要介绍了Simatic S7-1200 PLC和Sinamics V20变频器在卷绕机上的应用。基于SinamicsV20变频器的自由功能块功能,在变频器中进行逻辑控制,实现卷绕机的断线、起停、定时提醒功能:(1)基于SinamicsV20变频器的PID功能,实现卷绕机的... 本文主要介绍了Simatic S7-1200 PLC和Sinamics V20变频器在卷绕机上的应用。基于SinamicsV20变频器的自由功能块功能,在变频器中进行逻辑控制,实现卷绕机的断线、起停、定时提醒功能:(1)基于SinamicsV20变频器的PID功能,实现卷绕机的运行速度控制;(2)基于Simatic S7-1200 PLC和Sinamics V20变频器的Modbus通信功能,实现运行数据采集及分析显示。 展开更多
关键词 sIMATIC s7-1200 sINAMICs v20 自由功能块 PID MODBUs通信
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Question of Parity Non-conservation in Weak Interactions
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作者 Zuodong Sun 《Journal of Physical Science and Application》 2021年第2期33-49,共17页
In order to reasonably explain the phenomenon of cell bioelectricity,we proposed the conservation law of cell membrane area,established the ion inequality equation,and therefore paid attention to the mystery of“θ-τ... In order to reasonably explain the phenomenon of cell bioelectricity,we proposed the conservation law of cell membrane area,established the ion inequality equation,and therefore paid attention to the mystery of“θ-τ”.We researched and analyzed the“θ-τ”mystery,discussed the parity non-conservation in weak interactions,suggested possible experiments to test the parity non-conservation in weak interactions,and gave our research and analysis conclusions:The parity non-conservation in weak interactions,is still a“conjecture”;The experimental scheme suggested in the papers by C.N.Yang et al.cannot determine whether the weak interaction can separate left and right,and it is impossible to directly answer whetherθandτin the“θ-τ”mystery are the same particle;The Co60βdecay experiment such as C.S.Wu is a pseudo-mirror experiment,whether the experimental result violates parity conservation is only based on the assumption of C.N.Yang et al.In fact,experiments such as polarized Co60 did not overturn the so-called“law of parity conservation”.The mirror image principle does not have any physical meaning,does not correspond to any physical conservation quantity,and cannot be destroyed by any physical experiment.In the process of turning“mirror symmetry”and“mirror asymmetry”into so-called physical“common sense”and scientific“facts”respectively,the methods of transformation are“stealing concepts”and“circular argumentation”.The“θ-τ”mystery is a“man-made”mystery.θandτare two different particles,which may be the result of the same precursor particle being divided into two.The work of C.N.Yang,T.D.Lee,C.S.Wu et al.has brought quantum physicists from the“small black room”to the“bigger black room”or“smaller black room”.The right and wise choice is to go back through the door that came in.With the development of science today,it is time for some contents to reform from the bottom. 展开更多
关键词 Mystery ofθ-τ question of parity non-conservation C.N.Yang T.D.Lee C.s.Wu “origami windmill”model.
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基于直方图的快速Mumford-Shah模型MRI分割 被引量:4
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作者 张建伟 陈允杰 夏德深 《中国图象图形学报》 CSCD 北大核心 2005年第7期838-843,共6页
Mum ford-Shah(MS)模型因为其具有良好的图像分割能力,目前已被广泛应用于图像分割、目标跟踪等领域。但是由于其迭代过程需要对所有图像数据反复进行计算,因而其时间效率很低,难以实时应用。针对这个缺点,根据医学核磁共振图像(MR I)... Mum ford-Shah(MS)模型因为其具有良好的图像分割能力,目前已被广泛应用于图像分割、目标跟踪等领域。但是由于其迭代过程需要对所有图像数据反复进行计算,因而其时间效率很低,难以实时应用。针对这个缺点,根据医学核磁共振图像(MR I)的特点,对M-S模型进行了改进,提出了一种基于直方图的快速求解方法,其求解时,首先构造符号表,以区分曲线内外区域;然后利用直方图法来进行目标的快速粗分割,再通过遍历优化边界,来获得较精确的分割。对MR图像进行的分割实验表明,其分割效果更好,同时,时间效率也有大幅提高,这就方便了实时应用。 展开更多
关键词 M-s模型 C-v模型 直方图 区域信息 MRI分割
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S7-200PLC在中水回用气水反冲洗DA型滤池中的应用 被引量:7
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作者 孔德鹏 廖家平 《电气应用》 北大核心 2005年第6期28-29,32,共3页
引言 气水反冲均料滤池是以法国Degvemnt公司V型滤池为基础,结合我国的实际情况发展的一种新滤池,DA超高速D型滤池是经彗星式纤维滤料为核心的高效过滤技术,该种滤池结合了纤维滤料截污性能好与颗粒滤料反冲效果好的特性有很好应用价值... 引言 气水反冲均料滤池是以法国Degvemnt公司V型滤池为基础,结合我国的实际情况发展的一种新滤池,DA超高速D型滤池是经彗星式纤维滤料为核心的高效过滤技术,该种滤池结合了纤维滤料截污性能好与颗粒滤料反冲效果好的特性有很好应用价值.河南平顶山市中水回用工程中采用了这种气水反冲洗DA型滤池.滤池在中水处理中占有很重要的地位,传统的中水厂常采用常规的继电器进行控制,控制线路过于繁琐复杂不便于维护,且故障率高,因此为了提高自动化水平,对新建中水厂采用微型PLC作为该控制系统的核心,实现现场自动化控制,提高气水反冲DA型滤池的工作可靠性. 展开更多
关键词 s7-200PLC 气水反冲洗 A型 彗星式纤维滤料 中水回用工程 v型滤池 过滤技术 应用价值 平顶山市 超高速 基础
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基于S7-1200PLC的立体仓库高精度存取控制系统设计 被引量:5
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作者 党媚 《电子设计工程》 2021年第9期61-65,70,共6页
针对实现智能仓库不同仓位精确定位及状态更新的目的,通过方案及元器件选型、硬件电路构建、控制程序编程等环节,完成控制系统设计,其核心是采用三轴伺服运动控制的方式实现行李检测及各仓位精确定位。主要介绍伺服驱动系统构建、S7-120... 针对实现智能仓库不同仓位精确定位及状态更新的目的,通过方案及元器件选型、硬件电路构建、控制程序编程等环节,完成控制系统设计,其核心是采用三轴伺服运动控制的方式实现行李检测及各仓位精确定位。主要介绍伺服驱动系统构建、S7-1200PLC运动控制向导组态及轴运动程序编写、S7-1200PLC写入域和读取域指令实现各仓位状态读取和更新的方法。通过实施和测试验证了该方法的可靠性,为工业应用提供了可借鉴性。 展开更多
关键词 s7-1200PLC TIAPortal v15 伺服定位 写入域和读取域
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基于S7-1200的运料小车控制系统设计 被引量:4
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作者 张强 《机电信息》 2019年第18期128-129,共2页
重点阐述了运料小车控制系统控制方案设计、硬件设计、程序设计及HMI设计,采用TIA博途全集成自动化软件平台和S7-1200控制器,实现运料小车控制系统的精确、安全和有效控制,提高了生产效率。
关键词 运料小车 s7-1200 TIAPortal KTP700 v20
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