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41.
作为存储测试系统配套的信息处理软件,有一个直观的汉字界面显的非常必要,本文介绍一种在西文DOS下快速显示汉字的处理技术:由信息处理软件原程序中的汉字信息通过访问硬盘汉字库生成,由所需显示汉字点阵构成具有专用格式的专用汉字库,通过软件编程可实现对汉字库的快速访问与快速显示。从而,即节省磁盘空间,又能使信息处理软件与汉字显示很好地溶为一体。 相似文献
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本文首先运用卫星影像,对临汾—运城盆地中主要活动断层的平面展布状况进行了解译。在此基础上,利用天然地震震源点的三维生标,探索性地研究与确定了各条断层的深部延伸性状,建立起了盆地内断裂构造的三维格架。主要结论有:(1)边缘断裂多数是深达莫霍面的(38km)伸展性铲形断裂;(2)霍山西麓山前大断裂的深部延伸为直立状,深度达莫霍面(38km)。(3)盆地内的其它断层多数是铲形断层的对偶断层,产状为倾斜状,与铲形断层相遇后而终止,延伸深度一般不超过30km;(4)区内存在4个水平滑脱面(或层),其深度分别为4.5~5.5km,9.5~10.5km,18.5~20.5km,35.5~37.5km,这些面(或层上)震源点分布较密集;(5)区内北部、中部、南部,断层组合形式稍有差别,并控制、形成了不同的地貌形态。 相似文献
44.
串行传输技术具有更高的传输速率和更低的设计成本,被广泛应用于高速通信领域;研究了一种基于FPGA的LVDS高速数据传输系统方案,该方案以Altera FPGA芯片为核心,通过其LVDS I/O口稳定可靠地完成数据传输,系统采用Verilog语言完成8B/10B编解码、时钟数据恢复、CRC校验、字节边界调整、误码率测试模块等;通过实验表明,该方案既满足了长距离和高速数据传输的要求,又降低了系统成本。 相似文献
45.
This paper addresses the problem of semi‐global stabilization by output feedback for a class of nonlinear systems whose output gains are unknown. For each subsystem, we first design a state compensator and use the compensator states to construct a control law to stabilize the nominal linear system without the perturbing nonlinearities. Then, combining the output feedback domination approach with block‐backstepping scheme, a series of homogeneous output feedback controllers are constructed recursively for each subsystem and the closed‐loop system is rendered semi‐globally asymptotically stable. 相似文献
46.
Dihua Zhai Yu Kang Ping Zhao Yun-Bo Zhao 《International Journal of Control, Automation and Systems》2012,10(6):1182-1192
The stability of a class of switched stochastic nonlinear retarded systems with asynchronous switching controller is investigated. By constructing a virtual switching signal and using the average dwell time approach incorporated with Razumikhin-type theorem, the sufficient criteria for pth moment exponential stability and global asymptotic stability in probability are given. It is shown that the stability of the asynchronous stochastic systems can be guaranteed provided that the average dwell time is sufficiently large and the mismatched time between the controller and the systems is sufficiently small. This result is then applied to a class of switched stochastic nonlinear delay systems where the controller is designed with both state and switching delays. A numerical example illustrates the effectiveness of the obtained results. 相似文献
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48.
Yuning Lou Yajuan Dong Xiaoyong Wang Feirong Gong Min Zhao Zongming Rong 《Journal of surfactants and detergents》2021,24(1):3-13
Two generations of novel linear-dendritic carboxylate surfactants C18-G1-(COONa)2 and C18-G2-(COONa)4 have been synthesized by the divergent method and their structures are characterized by 1H Nuclear Magnetic Resonance and Infrared analysis. The electrical conductivity measurement is used to measure the Krafft temperatures of C18-G1-(COONa)2 and C18-G2-(COONa)4, which are much smaller than those of the corresponding conventional surfactant sodium stearate. The markedly enhanced solubility of two linear-dendritic surfactants is ascribed to the high hydrophilicity of surfactant headgroups induced by the carboxylate and ester groups. The critical micelle concentration (CMC) values obtained from both the electrical conductivity and surface tension measurements indicate that the micellizations of linear-dendritic surfactants become favorable with the increase in the number of the surfactant headgroup. However, the surface activity parameters including the surface tension at the CMC, maximum surface excess, and minimum surface area reveal that C18-G1-(COONa)2 exhibits greater efficiency in absorbing at the air/water interface compared to C18-G2-(COONa)4, owing to their different steric repulsions of the surfactant headgroups. In addition, C18-G1-(COONa)2 and C18-G2-(COONa)4 have higher emulsifying ability than the conventional surfactants sodium stearate and sodium octadecyl sulfate. 相似文献
49.
Weichen Zhu Yuxuan He Minman Tong Xiaoyong Lai Shijia Liang Xu Wang Yanjuan Li Xiao Yan 《中国化学工程学报》2021,33(5):118-124
CH_4 storage associated with adsorbed natural gas(ANG) technology is an issue attracting great concern.Following the Advanced Research Project Agency-Energy(ARPA-E) targeted deliverable capacity of 315 cm~3·cm~(-3)(STP), hundreds of thousands of materials have been experimentally or theoretically evaluated,while the best results still show a 35% gap from the target. Moreover, recent theoretical research reveals that the target is beyond the possibility that real materials can be designed. To get rid of the awkward situation, we make attempts on investigating the CH_4 delivery performance under other operation conditions. Methods of raising the discharge temperature(to infinite high) or elevating the storage pressure(to 25 MPa) have been proved to show limited effectiveness. In this work, it is found that the ARPA-E target can be achieved by using a decreasing storage temperature strategy. By taking 280 Co RE(computation-ready, experimental) COFs(covalent organic frameworks) as ANG materials, when reduce the storage temperature to 190.6 K, the highest deliverable capacity can reach 392 cm~3·cm~(-3)(STP), and16.1% Co RE COFs can surpass the target. The target is also achievable when storage at 220 K. Structure performance relationships study shows strong correlation between deliverable capacity and void fraction. Hence, 120 hypothetical COFs are generated to ascertain the optimum void fraction. In addition,the performance of 2 D-COFs can be greatly enhanced by increasing the interlayer spacings, e.g. CH_4 deliverable capacity(storage at 190.6 K) of ATFG-COF can be improved from 239 to 411 cm~3·cm~(-3)(STP) when interlayer spacing is enlarged to 1.65 nm. 相似文献
50.
Pengtao Zhai Mingyang Liu Wenying Zhou Liugang Chen Dafei Ding Guotian Ye 《International Journal of Applied Ceramic Technology》2021,18(3):1017-1024
Refractory materials such as mullite, andalusite, forsterite, and cordierite are generally used to prepare saggers for the calcination of Li-ion battery Li(NixCoyMnz)O2 (LNCM) cathode material. However, these compounds are prone to be attacked by the LNCM materials, thereby leading to short life spans and contamination of the Li-ion battery cathode materials. To improve the corrosion resistance of refractory sagger materials, the most clear cut-way is enhancing the corrosion resistance of matrix using a new refractory component. Potassium aluminate (K2O·11Al2O3, KA11) with an excellent corrosion resistance against alkaline oxide was synthesized via solid-state method using potassium carbonate (K2CO3) and industrial alumina powder (Al2O3). Interactions between KA11 and LNCM cathode materials at 800°C–1100°C were characterized by refractory-LNCM precursor laboratory-scale tests to understand the corrosion behavior of KA11. The microstructure and phase composition of synthesized KA11 and the calcined KA11-LNCM mixture cylinders were analyzed with SEM and XRD. The observations reveal that KA11 shows a better corrosion resistance to LNCM materials compared with mullite, cordierite, and forsterite. The addition of synthesized KA11 also favors the thermal shock resistances of mullite-based sagger materials. 相似文献