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61.
Sekiguchi K. Seki Y. Okitani N. Fukuda M. Critchley S. Habib W.G. Hartman D. Shaw K. 《Industry Applications, IEEE Transactions on》1996,32(3):608-616
The new coupled pickle line and cold mill (CPCM) has been processing steel since December 1991 at Dofasco Inc. in Hamilton, Ontario, Canada. This mill rolls both sheet and tin plate. The work rolls for the last stand are often textured by grit blasting to roll “matte” finished strip. A new computer-targeted control system was developed for the roll speeds and gaps, specifically for matte rolling. The new set-up system uses Stone's model, which is more appropriate for the limited reductions evident with the rougher rolls. Conventional automatic gauge control (AGC) systems using thickness measurements after the last stand are limited in performance by the effect of long transport delays. These limitations are particularly critical during mill acceleration and deceleration. The use of a thickness gauge before the stand with matte rolls allows the development of AGC systems using shorter control loops for final gauge control. The AGC system uses a Smith predictor for transport lag, (phase shift), and compensation. The combination of the shorter AGC loop and the Smith predictor allows higher gains to be used in the control system. This set-up and control system has contributed to Dofasco's position as a market leader in thickness performance 相似文献
62.
63.
P Ambrosi G Habib R Gélisse J Yao A Ferracci B Kreitmann D Métras P Bernard G Bouvenot R Luccioni 《Canadian Metallurgical Quarterly》1998,47(5):334-339
Side effects of morphine are common when given in titrated doses to control severe pain in advanced cancer. We report a case series of acutely ill cancer patients suffering from pain, complications of advanced disease, and opioid side effects. They were treated with intravenous (i.v.) ketorolac along with i.v. morphine using repeated dosing. Excellent pain relief with improvement in the opioid bowel syndrome was achieved. We found it possible to switch from IV ketorolac to oral ketorolac along with oral morphine for long-term pain control. Ketorolac can be well tolerated in high-dose, long-term use even in this frail patient population. An algorithm is presented for the suggested use of ketorolac as a morphine sparing agent. Potential methods for studying ketorolac further in this role are discussed. 相似文献
64.
Hamam H 《Applied optics》2003,42(35):7052-7059
The fractional Talbot effect brings into play a superimposition of shifted and complex weightedreplicas of the original object. This phenomenon can be used to replicate images of nonperiodic objects by means of Talbot array illuminators. These diffractive elements can also be used to concentrate replicas into a single image. These techniques are useful for several applications such as beam shaping. 相似文献
65.
The paper derives a spiral condition, for a single Pythagorean hodograph quintic transition curve of G2 contact, between two circles with one circle inside the other. A spiral is free of local curvature extrema, making spiral designs an interesting mathematical problem with importance for both physical and aesthetic applications. In the construction of highways or railway routes in particular, it is often desirable to have a transition curve from circle to circle. Here, we treat an open problem on planar quintic spiral segments, called transition curve elements, examine techniques for curve design using the new results, and derive lower and upper bounds for the distance between the two circles. The proposed method is applicable for non-tangent and non-concentric circles. 相似文献
66.
M irghasem Hosseini Habib Ashassi-Sorkhabi Heshmat Allah Yaghobkhani Ghiasvand 《中国稀土学报(英文版)》2007,25(5):537-543
A A cerium-based chemical conversion process was studied. First, zinc coating obtained from a free-cyanide alkaline bath, with derivative of imidazol with new brightener, was investigated, zinc-plated steel specimens were treated with a solution of 50 mmol· L^-1 Ce(NO3 )3 The corrosion behavior of bare and treated mild galvanized steel was evaluated during exposure to 0.5 mol · L^-1 NaCl for different immersion time, using Tafel polarization curves and electrochemical impedance spectroscopy (EIS) measurements. The surface morphology of the coating was studied using scanning electron microscopy (SEM). The composition and chemical percent of the coating were examined by X-ray dispersion energy (EDAX). The results of these measurements showed that the newly developed cerium-based conversion coating process was a promising candidate for replacing the conventional chromate treatments used at present for galvanized steel. 相似文献
67.
An approach for fabricating functionally graded specimens of supernickel alloy and ceramic compositions via Selective Laser Melting (SLM) is presented. The focus aimed at using the functionally graded material (FGM) concept to gradually grade powdered compositions of Zirconia within a base material of Waspaloy®. A high power Nd:YAG laser was used to process the material compositions to a high density with gradual but discrete changes between layered compositions. The graded specimens initially consisted of 100% Waspaloy® with subsequent layers containing increased volume compositions of Zirconia (0–10%). Specimens were examined for porosity and microstructure. It was found that specimens contained an average porosity of 0.34% with a gradual change between layers without any major interface defects. 相似文献
68.
There is a real need to develop a sensory system that can monitor and track the behavioral status of a person in real time while protecting his/her privacy. In addition, it is important to have the ability to detect stationary and moving objects in real time to support dynamic navigation needs for mobile robots. This paper describes the development of intelligent fiber-grating (FG)-based 3-D vision sensory system that enables real-time object detection, monitoring, and tracking. This system uses the richness and the strength of the vision while reducing the data load and computational cost by encoding the working space using a limited number of spatially interrelated 2-D laser spots. The sensor system generates the laser spots by projecting a coherent laser beam on two perpendicularly overlaid layers of FGs. The presence of a target within the visible operational view of the sensor disturbs the part of the projected laser spots' pattern where the target appeared. By calculating the displacement of the disturbed spots within the CCD image plane, the sensor system can detect, in a short time, an object/human and provide relevant information in terms of range, approximate shape, and position. To facilitate faster detection and real-time tracking, the author has developed two strategies that decompose the working space into zones and virtual planes 相似文献
69.
G. Zhou O. Baysal J. Kaye S. Habib C. Wang 《International journal of remote sensing》2013,34(14):2667-2685
This paper presents a concept design of an envisioned future intelligent Earth observing satellite (FIEOS) system. The proposed system is a space-based architecture for the dynamic and comprehensive on-board integration of Earth observing sensors, data processors and communication systems. The architecture and implementation strategies suggest a seamless integration of diverse components into a smart, adaptable and robust Earth observation satellite system. It is intended to enable simultaneous, global measurements and timely analyses of the Earth's environment for a variety of users. In particular, common users would directly access data in a manner similar to selecting a TV channel. We also discuss key technology problems, current technology development, amongst other things. It is concluded that (1) the proposed intelligent Earth observing satellite system is technically feasible; and (2) information technology and real-time information systems, for example multi-layer satellite networks connected with an organic system and on-board data processor capabilities, are crucial for implementation of the intelligent system. This revolutionary concept should dramatically impact on how Earth observing systems develop and conduct missions in the future. 相似文献
70.
Habib M. Ammari 《Computer Networks》2013,57(9):1913-1935
The design and development of multi-hop wireless sensor networks are guided by the specific requirements of their corresponding sensing applications. These requirements can be associated with certain well-defined qualitative and/or quantitative performance metrics, which are application-dependent. The main function of this type of network is to monitor a field of interest using the sensing capability of the sensors, collect the corresponding sensed data, and forward it to a data gathering point, also known as sink. Thus, the longevity of wireless sensor networks requires that the load of data forwarding be balanced among all the sensor nodes so they deplete their battery power (or energy) slowly and uniformly. However, some sensing applications are time-critical in nature. Hence, they should satisfy strict delay constraints so the sink can receive the sensed data originated from the sensors within a specified time bound. Thus, to account for all of these various sensing applications, appropriate data forwarding protocols should be designed to achieve some or all of the following three major goals, namely minimum energy consumption, uniform battery power depletion, and minimum delay. To this end, it is necessary to jointly consider these three goals by formulating a multi-objective optimization problem and solving it. In this paper, we propose a data forwarding protocol that trades off these three goals via slicing the communication range of the sensors into concentric circular bands. In particular, we discuss an approach, called weighted scale-uniform-unit sum, which is used by the source sensors to solve this multi-objective optimization problem. Our proposed data forwarding protocol, called Trade-off Energy with Delay (TED), makes use of our solution to this multi-objective optimization problem in order to find a “best” trade-off of minimum energy consumption, uniform battery power depletion, and minimum delay. Then, we present and discuss several numerical results to show the effectiveness of TED. Moreover, we show how to relax several widely used assumptions in order to enhance the practicality of our TED protocol, and extend it to real-world network scenarios. Finally, we evaluate the performance of TED through extensive simulations. We find that TED is near optimal with respect to the energy × delay metric. This simulation study is an essential step to gain more insight into TED before implementing it using a sensor test-bed. 相似文献