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151.
Pre- and/or post-compensators are designed to square down a general MIMO system to a uniform rank system, the structure of which is almost similar to a SISO system. The method of squaring down either does not change the finite zero structure of the given MIMO system or simply adds additional finite zeros in the left half s-plane. The significance of such a squaring down lies in the simplicity of the structure of a uniform rank system lending itself for easy analysis and control design.  相似文献   
152.
The problem of Langmuir probe data deformation due to RF pickup by the probe is treated through a computer simulation method. It is pointed out that proper RF compensations can be obtained by treatment of the Langmuir probe raw data through the use of computer software. It is demonstrated that correct, RF unaffected probe I–VIV characteristics can be accurately reproduced from the RF contaminated data. This eliminates the need for the use of any filters or other hardware procedures. User friendly matlab based software is presented. The software automatically retrieves the correct RF I–VIV characteristics for single Langmuir probe data which consequently allows for proper evaluation of plasma parameters such as the plasma electron temperature, electron number density and the electron energy distribution function (EEDF)  相似文献   
153.
In this work, RF MEMS continuous reversible variable inductor has been fabricated by using microelectronic technology and lamination process. We review, evaluate and compare this variable inductor with other work. The proposed inductor is a dual circular coil and has an inductance of few nH. The fundamental idea is to place a liquid droplet between the metal turns of a coil in order to modify the capacitive/resistive coupling between metal tracks and hence to change the stored magnetic energy. The SU-8 resin was used to realize the microfluidic channels and Au as metallic tracks. To prove the reversibility of the inductor, two cases were studied: filling and emptying of channels. The tuning range of the inductance is approximately 107 % at 1.6 GHz, making these devices very suitable as building blocks in many RF applications.  相似文献   
154.
The current work reports on the realization of movable micromachining devices using self-aligned single-mask fabrication process. Only dry etching process utilizing inductively coupled plasma reactive ion etching was used to release 3D micro structures from single crystal silicon substrate. No wet etching process is required to release the structures as is the case with silicon on insulator (SOI) wafers. Also the developed process does not require an SOI substrate and accordingly dispensing with the application of a wet etching step, thus yielding uniform structures without stiction. The optimized process was applied to realize thermally actuated microgrippers. The article presents the development of the fabrication process and demonstrates the operation of the fabricated device. The optimized process provides an avenue for low cost fabrication of movable micromachining devices without the use of complicated wet etching steps typically associated with SOI substrates.  相似文献   
155.
Nowadays, manufacturers have to share some of their resources with partners due to the competitive economic environment. The management of the availability periods of shared resources causes a problem because it is achieved by the scheduling systems, which assume a local environment where all resources are on the same site. Therefore, distributed scheduling with shared resources is an important research topic. In this communication, we introduce the architecture and behaviour of DSCEP framework (Distributed, Supervisor, Customer, Environment, and Producer) under shared resources situation with disturbances. We are using a simple example of manufacturing system to illustrate the ability of DSCEP framework to solve the shared resources scheduling problem in complex systems.  相似文献   
156.
Catalytic degradation of high-density polyethylene (HDPE) was carried out under nitrogen using a laboratory fluidised bed reactor operating at 360 °C with catalyst to polymer feed ratio of 2:1 and at 450 °C with catalyst to polymer feed ratio of 6:1 under atmospheric pressure. The catalysts used in this study were ZSM-5, US-Y, ASA, fresh FCC (fluid catalytic cracking) commercial catalyst (Cat-A) and equilibrium FCC catalysts with different levels of metal poisoning were studied. The initial results for polymer degradation at 360 °C (catalyst to polymer ratio of 2:1) in a fluidised bed reactor in terms of the yield of volatile hydrocarbon products were: model catalysts>commercial FCC catalyst>E-Cats. However, when the process conditions more closely resembled to FCC conditions, the fresh commercial FCC catalyst was more favourable in terms of the yield of volatile hydrocarbon products. The degradation of HDPE over E-Cats although reduced was similar to ASA in product selectivity and yield, and the level of metal contamination did not affect the product stream generated. A simple economic evaluation of polymer recycling process is reported showing that a catalytic system based on E-Cats appears comparable in costs to a commercial thermal cracking plant.  相似文献   
157.
The destruction of methyl-tert-butyl ether (MTBE) in contaminated waters by O3/H202 process was studied and the influence background COD, alkalinity, and hydrogen peroxide and MTBE concentrations on process treatment efficiency and ozone dosage was investigated. The treatment efficiency was evaluated by an Efficiency Index, which is based on electrical energy requirement for ozone production. It was found that the treatment efficiency decreases linearly with increasing concentrations of MTBE at constant background COD and with background COD at constant MTBE concentration. A simplified kinetic scheme was presented to account for these observations.  相似文献   
158.
In cloud computing, services play key roles. Services are well defined and autonomous components. Nowadays, the demand of using Fuzzy inference as a service is increasing in the domain of complex and critical systems. In such systems, along with the development of the software, the cost of detecting and fixing software defects increases. Therefore, using formal methods, which provide clear, concise, and mathematical interpretation of the system, is crucial for the design of these Fuzzy systems. To obtain this goal, we introduce the Fuzzy Inference Cloud Service (FICS) and propose a novel discipline for formal modeling of the FICS. The FICS provides the service of Fuzzy inference to the consumers. We also introduce four novel formal verification tests, which allow strict analysis of certain behavioral disciplines in the FICS as follows: (1) Internal consistency, which analyzes the service in a strict and delicate manner; (2) Deadlock freeness; (3) Divergence freeness; and (4) Goal reach ability. The four tests are discussed and the FICS is verified to ensure that it can pass all these tests.  相似文献   
159.
A good model of object shape is essential in applications such as segmentation, detection, inpainting and graphics. For example, when performing segmentation, local constraints on the shapes can help where object boundaries are noisy or unclear, and global constraints can resolve ambiguities where background clutter looks similar to parts of the objects. In general, the stronger the model of shape, the more performance is improved. In this paper, we use a type of deep Boltzmann machine (Salakhutdinov and Hinton, International Conference on Artificial Intelligence and Statistics, 2009) that we call a Shape Boltzmann Machine (SBM) for the task of modeling foreground/background (binary) and parts-based (categorical) shape images. We show that the SBM characterizes a strong model of shape, in that samples from the model look realistic and it can generalize to generate samples that differ from training examples. We find that the SBM learns distributions that are qualitatively and quantitatively better than existing models for this task.  相似文献   
160.
The Dokan Reservoir dam is a concrete cylindrical arch with gravity abutments, located on the Lesser Zab River about 60 km from the city of Sulaimani in north‐eastern Iraq. A bathymetric survey was conducted in November 2014 for a period of 10 days, using an echo sounder of 200‐kHz single beam. The survey results indicated an annual average sediment deposition of 3.8 million m3. Thirty‐two sediment samples were collected from the reservoir bed. The ratio of gravel, sand, silt and clay was 15:14:48:23, respectively. The reservoir bed is covered mainly with silt. The sediments are composed of silty clay (77.6%), silty sandy clay (10%), sandy gravely silty clay (1.2%) and gravely sandy silty clay (1%).  相似文献   
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