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1.
Xu  Furong  Liu  Ke  Yu  Zhuliang  Deng  Xin  Wang  Guoyin 《Neural computing & applications》2021,33(14):8513-8524
Neural Computing and Applications - It is a long-standing challenge to reconstruct the locations and extents of cortical neural activities from electroencephalogram (EEG) recordings, especially...  相似文献   
2.
In the field of water quality management, it is vital to determine the main precursory anomalies from the precursor of intricate water bloom in the context of a given area. In this paper, a water bloom precursor analysis method, based on two direction singular rough set, was proposed. This approach was produced on the basis of the different sections and pre-water bloom of water bloom precursor anomalies and characteristic of elements transferred in singular rough set. For testing the validity of two direction singular rough set application in water bloom precursor analysis, Xiangxi River, which is one of the typical tributaries of Three Gorges Reservoir in China, was selected as study area. The result showed that compared with other indexes, pH and dissolved oxygen (DO) are the most valuable indicators of water bloom in the precursory anomalies. Furthermore, regarding with water bloom precursory anomalies in Xiangxi River, most of the nutrient loading and biological community are the key indicators. Hence, this method can determine the main precursory anomaly for water bloom in the study area, which provides powerful knowledge support to water quality specialists for them to comprehensively analyze precursory anomaly so as to find out its relationship with occurrence law of water bloom.  相似文献   
3.
The extraction behavior and mechanism of gallium(Ⅲ) and thallium(Ⅰ) or indium(Ⅲ) and thallium(Ⅰ) with Sec-octylphenoxy acetic acid (CA-12) from hydrochloric acid solution in sulphonating kerosene were studied. Optimum extraction conditions were evaluated from critical study of various experimental parameters and the probable composition of the extracted species is ascertained from lg D-lg C plots. The effects of different ions on the determination of these ions were examined.  相似文献   
4.
TMLNN: triple-valued or multiple-valued logic neural network   总被引:2,自引:0,他引:2  
We discuss the problem of representing and processing triple-valued or multiple-valued logic knowledge using neural network. A novel neuron model, triple-valued or multiple-valued logic neuron (TMLN), is presented. Each TMLN can represent a triple-valued or multiple-valued logic rule by itself. We will show that there are two TMLNs: TMLN-AND (triple-valued or multiple-valued "logic AND") neuron and TMLN-OR (triple-valued or multiple-valued "logic OR") neuron. Two simplified TMLN models are also presented, and show that a multilayer neural network made up of triple-valued or multiple-valued logic neurons (TMLNN) can implement a triple-valued or multiple-valued logic inference system. The training algorithm for TMLNN is presented and can be shown to converge. In our model, triple-valued or multiple-valued logic rules can be extracted from TMLNN with ease. TMLNN can thus form a base for representing logic knowledge using neural network.  相似文献   
5.
设计并实现了一种基于Lotus Notes的分布式信息邮政商业信函系统,并研究了系统实现过程中的两个关键技术。  相似文献   
6.
含B2O3无氟连铸保护渣物理性能的研究   总被引:3,自引:2,他引:3  
常规保护渣中配入的助熔剂一般是氟化物和Na2O,但二者都对环境产生严重污染。为此试验研究了含助熔剂B2O3保护渣及其熔点、粘度、结晶性能和表面张力等物理性能。试验表明,当保护渣碱度(CaO/SiO2)等于0.88,成分(%)为37.91CaO-43.09SiO2—5Al2O3—5MgO-2Li2O-7B2O3时的熔点909℃,熔化性温度1160℃,1300℃粘度值0.40Pa.s,1300℃表面张力值0.32N/m,能满足常规钢种和部分特殊钢种对连铸保护渣的使用要求。  相似文献   
7.
An integration of multi-angle energy-dispersive x-ray diffraction and ultrasonic elastic wave velocity measurements in a Paris-Edinburgh cell enabled us to simultaneously investigate the structures and elastic wave velocities of amorphous materials at high pressure and high temperature conditions. We report the first simultaneous structure and elastic wave velocity measurement for SiO(2) glass at pressures up to 6.8 GPa at around 500°C. The first sharp diffraction peak (FSDP) in the structure factor S(Q) evidently shifted to higher Q with increasing pressure, reflecting the shrinking of intermediate-range order, while the Si-O bond distance was almost unchanged up to 6.8 GPa. In correlation with the shift of FSDP position, compressional wave velocity (Vp) and Poisson's ratio increased markedly with increasing pressure. In contrast, shear wave velocity (Vs) changed only at pressures below 4 GPa, and then remained unchanged at ~4.0-6.8 GPa. These observations indicate a strong correlation between the intermediate range order variations and Vp or Poisson's ratio, but a complicated behavior for Vs. The result demonstrates a new capability of simultaneous measurement of structures and elastic wave velocities at high pressure and high temperature conditions to provide direct link between microscopic structure and macroscopic elastic properties of amorphous materials.  相似文献   
8.
云南昌宁锡矿石主要有用金属矿物为锡石,其次为褐铁矿等,主要脉石矿物为石英,锡主要以锡石及酸溶锡形式存在。原矿Sn品位为0.166%,−0.074 mm矿泥含量为24.61%(其中−0.019 mm矿泥含量为14.27%),属低品位、高泥、含铁难选锡石矿。本文在对该矿石进行原矿性质研究的基础上,开展了该矿的重-磁选工艺研究。结果表明:原矿破碎至−12 mm按0.212 mm粒度洗矿分级,洗矿+0.212 mm粗粒破碎至−3 mm后磨矿至−0.074 mm 55.85%与洗矿细粒−0.212 mm合并,采用螺旋溜槽预先抛尾-溜槽精矿摇床分选-摇床精矿强磁选除铁的选矿工艺流程,可以获得产率为0.21%、Sn品位为41.32%、Sn回收率为52.27%的锡精矿,及产率为0.75%、Sn品位为4.750%、Sn回收率为21.46%的锡富中矿,锡精矿与锡富中矿Sn累计回收率为73.73%,锡精矿质量达到了YS/T339-2011标准中一类VII品级精矿质量要求,较好地实现了该锡矿的分选。  相似文献   
9.
针对液压系统在使用中故障频率较高、诊断方法受各种因素影响以及诊断准确率较低等问题,提出一种新的基于PSO-SVM模型的液压系统故障诊断方法.该方法首先对采集的故障信号数据进行预处理,使用自适应噪声完备集合经验模态分解(Complete EEMD with Adaptive Noise,CEEMDAN)结合模糊熵的方法进...  相似文献   
10.
本文以湖北某磁选尾矿中铜的综合回收为研究对象,通过工艺矿物学研究表明,该磁选尾矿组分较为复杂,铜含量较低为0.38%,嵌布粒度较细,铜主要赋存于原生硫化铜中,分布率为74.08%,铜矿物主要是黄铜矿,少量铜蓝、辉铜矿等,脉石矿物主要是石英,其次为方解石、白云石、绢云母,少量长石、高岭石等。针对尾矿中铜矿物“贫、细、杂”的特点,采用CCF浮选柱进行回收铜的选矿实验研究,研究结果表明,经过一次粗选一次扫选和两次精选作业,可从含铜0.38%的尾矿中获得铜品位16%以上,铜回收率76% 以上的铜精矿,实验指标良好,实现矿产资源综合回收利用。  相似文献   
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