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81.
An intelligent verification platform based on a structured analysis model is presented.Using an abstract model mechanism with specific signal interfaces for user callback,the unified structured analysis data,shared by the electronic system level design,functional verification,and performance evaluation,enables efficient management review,auto-generation of code,and modeling in the transaction level.We introduce the class tree,flow parameter diagram,structured flow chart,and event-driven finite state machine as structured analysis models.As a sand table to carry maps from different perspectives and levels via an engine,this highly reusable platform provides the mapping topology to search for unintended consequences and the graph theory for comprehensive coverage and smart test cases.Experimental results show that the engine generates efficient test sequences,with a sharp increase in coverage for the same vector count compared with a random test.  相似文献   
82.
采用十八烷基三甲基氯化铵(OTAC)作为有机插层剂对海泡石进行了有机化处理,该有机化的海泡石粒子在苯乙烯单体中很容易地均匀分散并形成稳定的胶体溶液.通过对分散有海泡石的苯乙烯进行原位插层聚合制备了聚苯乙烯/海泡石纳米复合材料.并用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)和透射电镜(TEM)对聚苯乙烯/海泡石复合材料的结构进行了表征.研究表明聚苯乙烯的大分子链插入到海泡石片层间,形成了部分插层、部分剥离型纳米复合材料.  相似文献   
83.
Cu2O nanocactuses were synthesized via a simple, low-temperature, and no time-consuming wet chemical route. The synthesized products were systematically studied by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the formation of Cu2O nanocactuses was strongly depended on the addition of CTAB and NaOH. The structural evolution of the cactuslike Cu2O was found to follow dissolution and recrystallization processes. It is noteworthy that the stepwise synthetic procedure was crucial to the growth of the final nanoarchitectures. UV–vis spectrum was also used to estimate the absorption and photodegradation ability of the nanocactuses.  相似文献   
84.
通过对国产纸膜和日本滤纸膜材料的分析研究,研制出NIMTE异相膜,并在空气能量回收装置使用过程中对风压、空气流量、热流方向与热交换效率、回收能量、能效及安全性的关系进行分析,设计出能够更好发挥异相膜使用效果的传热膜机芯,有效提高空气能量回收装置的综合性能。  相似文献   
85.
One-dimensional (1D) ZnO microwires were successfully synthesized by chemical vapor deposition and their structural and morphological properties were analyzed by X-ray diffraction and scanning electron microscopy, demonstrating that the microwires were single crystalline with perfect hexagonal structure and smooth surface. Using these 1D microstructures, we fabricated a novel ZnO-based ethanol gas sensor. Operating at room temperature, the sensor was found to have good sensing characteristics. The reliability and stability of the sensor could be improved by connecting multiple 1-wire devices (1-WD) in parallel into a multi-wires device. In interior natural lighting environment and under 3 V bias, the response and recovery time of the 1-WD to 200 ppm ethanol gas were <10 s and about 300 s, respectively, and the minimum and maximum detection limit were about 2 and 200 ppm, respectively. A sensing model was proposed for discussing the performance of the sensor. The simplicity in fabrication, low power consumption and low cost make the sensor suitable for practical application in many fields, especially in identifying driving under the influence and chemical industry monitoring.  相似文献   
86.
Although some progress has been made on stretchable supercapacitors, traditional stretchable supercapacitors fabricated by predesigning structured electrodes for device assembling still lack the device‐level editability and programmability. To adapt to wearable electronics with arbitrary configurations, it is highly desirable to develop editable supercapacitors that can be directly transferred into desirable shapes and stretchability. In this work, editable supercapacitors for customizable shapes and stretchability using electrodes based on mechanically strengthened ultralong MnO2 nanowire composites are developed. A supercapacitor edited with honeycomb‐like structure shows a specific capacitance of 227.2 mF cm?2 and can be stretched up to 500% without degradation of electrochemical performance, which is superior to most of the state‐of‐the‐art stretchable supercapacitors. In addition, it maintains nearly 98% of the initial capacitance after 10 000 stretch‐and‐release cycles under 400% tensile strain. As a representative of concept for system integration, the editable supercapacitors are integrated with a strain sensor, and the system exhibits a stable sensing performance even under arm swing. Being highly stretchable, easily programmable, as well as connectable in series and parallel, an editable supercapacitor with customizable stretchability is promising to produce stylish energy storage devices to power various portable, stretchable, and wearable devices.  相似文献   
87.
The development of transition metal dichalcogenides has greatly accelerated research in the 2D realm, especially for layered MoS2. Crucially, the metallic MoS2 monolayer is an ideal platform in which novel topological electronic states can emerge and also exhibits excellent energy conversion and storage properties. However, as its intrinsic metallic phase, little is known about the nature of 2D 1T′‐MoS2, probably because of limited phase uniformity (<80%) and lateral size (usually <1 µm) in produced materials. Herein, solution processing to realize high phase‐purity 1T′‐MoS2 monolayers with large lateral size is demonstrated. Direct chemical exfoliation of millimeter‐sized 1T′ crystal is introduced to successfully produce a high‐yield of 1T′‐MoS2 monolayers with over 97% phase purity and unprecedentedly large size up to tens of micrometers. Furthermore, the large‐sized and high‐quality 1T′‐MoS2 nanosheets exhibit clear intrinsic superconductivity among all thicknesses down to monolayer, accompanied by a slow drop of transition temperature from 6.1 to 3.0 K. Prominently, unconventional superconducting behavior with upper critical field far beyond the Pauli limit is observed in the centrosymmetric 1T′‐MoS2 structure. The results open up an ideal approach to explore the properties of 2D metastable polymorphic materials.  相似文献   
88.
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite (PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique, which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion, by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as an injectable vehicle for local therapy of bone defect.  相似文献   
89.
仿生眼的研究现状与发展趋势   总被引:10,自引:2,他引:10  
邹海荣  龚振邦  罗均 《机器人》2005,27(5):469-474
首先,在分析人眼眼球运动的特点和形式的基础上,详细介绍了国内外仿生眼研究对扫视性眼球运动、平滑性眼球运动、异向眼球运动、前庭动眼反射、视动反射等的模仿,最后总结了仿生眼研究的特点和发展趋势.  相似文献   
90.
系统以工控机为中心,配以高性能的模块化外设组成一体化的计算机控制系统。采用温度控制外环和电流平衡控制内环的双环路结构来具体实现交流电弧炉温度和三相电流平衡的智能集成控制。外环采用模糊、神经网络和优化决策共同控制,内环则采用模糊专家解耦控制。系统能实时自适应炉况状态的变化,提高生产效率,降低电能及电极消耗。实际运行证明该系统具有良好的鲁棒性和实时性。  相似文献   
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