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1.
A new method for fabrication nano-porous aluminum grating array   总被引:1,自引:0,他引:1  
The fabrication technique of highly ordered anodic porous alumina membrane by anodization of Al and the obtained membrane as a mask to the fabrication of 100 nm period antireflection grating hole are described. The two-step anodizing process improves the quality of the nanohole because the periodic seeds are generated by the first anodization. Antireflection grating structures are fabricated by using ordered anodic porous alumina mask and etched by SF6 fast atom beam on silicon wafer. The reflectivity of the antireflection grating structures is measured and compared with that of the calculated value and the polished silicon surface.A part of this work was performed in Venture Business Laboratory in Tohoku University, Japan.  相似文献   

2.
Abstract— The fabrication technique for color OLED panels by means of wettability‐controllable hole‐injection material (HIM) and a photocatalytic lithography method achieves both precise ink‐jet printing and long‐lifetime devices. The technique enables us to selectively change the non‐wetting surface of a hole‐injection layer (HIL) of metal‐oxide nanoparticles (MONPs) into a wetting surface without damage to the device performance. Wetting patterns formed by this method with photocatalyst‐coated photomasks made it possible to print emission material with patterns of precisely 98‐μm widths on the hole‐injection layer. A fluorescent green‐emitting device fabricated with an HIM of MONPs by the photocatalytic treatment exhibited a long lifetime of 365 hours at30,000 cd/m2, which can be extrapolated to a lifetime of more than 110,000 hours at 1000 cd/m2, assuming an acceleration coefficient of 1.7. A two‐color device and a monochrome passive‐matrix panel were also successfully fabricated. The two‐color device emitted light without the mixing of colors. The monochrome panel displayed alphabetical characters with good uniformity and no flaws.  相似文献   

3.
辛海良  胡剑波 《控制与决策》2011,26(12):1824-1828
研究影响一般滑动模态变结构控制性能的因素,并给出了根据切换函数选择滑动模态系数、边界层厚度以及控制器增益系数的一般要求.针对一类含参数不确定性的非线性系统,采用新型增益调度变结构控制策略进行控制,以切换函数作为调度变量对滑动模态系数、边界层厚度以及控制器增益系数进行调度,以提高滑动模态变结构控制系统的控制性能,抑制颤振,降低控制能耗.仿真算例验证了所提出控制策略的有效性.  相似文献   

4.
We have developed a new type of non-contact three-dimensional photo-thermal etching method for agar microculture chips exploiting the characteristics of two different wavelengths of infrared laser beams. We used two different wavelengths of infrared (1480 and 1064 nm) focused laser beam as a heat source to melt and remove a portion of 200 μm high agar gel layer on the 5 nm thick chromium-coated glass slide. As the 1480 nm infrared beam is absorbed by water, the agar gel on the light pathway is heated and melted. On the other hand, as the 1064 nm infrared beam is not absorbed by water and agar, the melting of the agar occurred just near the chromium thin layer that absorbs 1064 nm infrared light. Using this non-contact etching, we can easily make microstructures in agar-layer using infrared laser beam only within a few minutes; i.e. cell-culture holes are melted by 100 mW, 1480 nm laser and tunnels by 100 μm/s, 40 mW, 1064 nm laser, respectively. The size of holes and tunnels were also controlled by choosing the irradiation power and time of infrared lasers. Those results indicate that we can make and use microstructures for biological use without any expensive microfablication facilities nor a series of complicated procedure and time.  相似文献   

5.
We report the original design of a new type of electronic nose (e-nose) consisting of only five sensors made of hierarchically structured conductive polymer nanocomposites (CPC). Each sensor benefits from both the exceptional electrical properties of carbon nanotubes (CNT) used to build the conductive architecture and the spray layer by layer (sLbL) assembly technique, which provides the transducers with a highly specific 3D surface structure. Excellent sensitivity and selectivity were obtained by optimizing the amount of CNT with five different polymer matrices: poly(caprolactone) (PCL), poly(lactic acid) (PLA), poly(carbonate) (PC), poly(methyl methacrylate) (PMMA) and a biobased polyester (BPR). The ability of the resulting e-nose to detect nine organic solvent vapours (isopropanol, tetrahydrofuran, dichloromethane, n-heptane, cyclohexane, methanol, ethanol, water and toluene), as well as biomarkers for lung cancer detection in breath analysis, has been demonstrated. Principal component analysis (PCA) proved to be an excellent pattern recognition tool to separate vapour clusters.  相似文献   

6.
7.
This paper presents a new control method for a class of nonlinear switched systems in strict feedback form with a state constraint. In the proposed approach, a nonlinear mapping is first introduced to transform the problem of controlling the switched system with state constraint to a new problem of regulating the transformed system without a constraint. By using the backstepping technique, the designed state-feedback controller ensures that the corresponding closed-loop system is asymptotically stable without violation of the constraint, and that all closed-loop signals keep bounded. Furthermore, we explore the use of a coordinate transformation to deal with an asymmetric state constraint as a generalised approach. In the end, an application example on a chemical process is shown to demonstrate the efficacy of the obtained results.  相似文献   

8.
《Journal of Process Control》2014,24(9):1402-1411
This paper presents a new method to calculate the feedback control gain for a class of multivariable bilinear system, and also applied this method on the control of two sections of paper-making process with disturbance. The robust H∞ control problem is to design a state feedback controller such that the robust stability and a prescribed H∞ performance of the resulting closed-loop system are ensured. The controller turns out to be robust with respect to the disturbance in the plant. Utilizing the Schur complement and some variable transformations, the stability conditions of the multivariable bilinear systems are formulated in terms of Lyapunov function via the form of linear matrix inequality (LMI). The gain of controller will be calculated via LMI. Finally, the application examples of a headbox section and a dryer section of paper-making process are used to illustrate the applicability of the proposed method.  相似文献   

9.
At the conceptual design stage, simplified finite element (FE) model of body-in-white (BIW) structure focuses on its specific merit to provide early-stage predictions for detailed FE model of that. This paper exploits a semi-rigid beam element (SRBE) that consists of a beam element with two semi-rigid connections at the ends to simulate the flexibility of joint. Guyan reduction method condenses the SRBE as a super element. A special finite element software for structural modeling and analysis of BIW (SMAB) is developed in .NET framework. The Unified Modeling Language is employed to depict the classes and their relationship. The design patterns are identified and applied in the framework design to facilitate communication and system expansion. Microsoft DirectX and GDI+ implement graphics display of spatial BIW frame and planar thin-walled cross section. Based on multi-threaded technology in .NET, subspace iteration method is paralleled to speed up the mode analysis. As a result, the efficiency of the SRBE is demonstrated by a benchmarking automotive body. Multi-threaded parallel is effective and useful, especially for frequency optimization.  相似文献   

10.
Online set-point optimisation which cooperates with model predictive control (MPC) and its application to a yeast fermentation process are described. A computationally efficient multilayer control system structure with adaptive steady-state target optimisation (ASSTO) and a suboptimal MPC algorithm are presented in which two neural models of the process are used. For set-point optimisation, a steady-state neural model is linearised online and the set-point is calculated from a linear programming problem. For MPC, a dynamic neural model is linearised online and the control policy is calculated from a quadratic programming problem. In consequence of linearisation of neural models, the necessity of online nonlinear optimisation is eliminated. Results obtained in the proposed structure are comparable with those achieved in a computationally demanding structure with nonlinear optimisation used for set-point optimisation and MPC.  相似文献   

11.
In this article, we consider a geometric process model for M/PH(M/PH)/1/K queue with new service machine procurement lead time. A maintenance policy (N???1,?N) based on the number of failures of the service machine is introduced into the system. Assuming that a failed service machine after repair will not be ‘as good as new’, and the spare service machine for replacement is only available by an order. More specifically, we suppose that the procurement lead time for delivering the spare service machine follows a phase-type (PH) distribution. Under such assumptions, we apply the matrix-analytic method to develop the steady state probabilities of the system, and then we obtain some system performance measures. Finally, employing an important Lemma, the explicit expression of the long-run average cost rate for the service machine is derived, and the direct search method is also implemented to determine the optimal value of N for minimising the average cost rate.  相似文献   

12.
This paper presents a novel compensation pixel circuit for active‐matrix organic light‐emitting diode displays, in which the coupling effect mask technology is developed to compensate the threshold voltage of driving thin‐film transistor whether it is positive or negative. Twenty discrete compensation pixel circuits have been fabricated by In‐Zn‐O thin‐film transistors process. It is measured that the non‐uniformity of the proposed pixel circuit is significantly reduced with an average value of 8.6%. Furthermore, the organic light‐emitting diode emission current remains constant during 6 h continuous operation, which also confirms the validity of the proposed pixel circuit.  相似文献   

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