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1.
2.
Jin B. Ong Osama K. Eyada PhD PE Abu S. Masud PhD PE 《Computers & Industrial Engineering》1989,17(1-4):85-89
This paper presents a Knowledge-based system (KBS) developed to allow users, who may not be knowledgeable about sensors, to select sensors suitable for their specific needs. The KBS runs on a micro-computer. The selection criteria are user specified and are based on the desired measurement parameters. The system output includes all of the operational and dimensional parameters of the recommended sensor, price, and vendor information. 相似文献
3.
Hypothermia induced by surface cooling has shown to protect vulnerable regions of the brain during an ischemic insult. This study evaluated the neuroprotective efficacy of neurotensin, a potent hypothermic agent, using a 5-min carotid occlusion procedure in the gerbil. In Experiment 1, the dose-response and time course of neurotensin-induced hypothermia were evaluated (n = 5/dose). Central infusion of 10, 20, and 30 micrograms neurotensin were found to significantly decrease core body temperature of conscious gerbils within 30 min of administration. In Experiment 2, gerbils pretreated with 30 micrograms neurotensin were permitted to become hypothermic or were maintained at 37 degrees-38 degrees C (rectal) during ischemic insult. Other gerbils were pretreated with peptide vehicle prior to ischemic insult (at 37 degrees -38 degrees C) or underwent a sham procedure (n = 6/condition). At 24 h after surgery, gerbils were tested for increased locomotor activity in an open-field apparatus. Gerbils pretreated with peptide vehicle or neurotensin and maintained at 37 degrees-38 degrees C during ischemia had significantly higher activity levels compared to the other treated groups. In contrast, gerbils made hypothermic with neurotensin exhibited activity levels similar to sham gerbils. Histological assessment revealed that neurotensin-induced hypothermia protected the CA1 region from ischemic damage. 相似文献
4.
Abu Avi Lupa Israel 《AEUE-International Journal of Electronics and Communications》2005,59(5):307-310
This letter presents a general analysis of time jitter in sigma-delta synthesizer. One of the practical applications of 1-bit sigma-delta systems is a generation of high-resolution local oscillator (LO) signals. In order to generate LO signals, one may use a single-bit sigma-delta technique to encode sine waves. Today, direct generation of high-frequency sine wave using a clock with higher frequency, is possible. In this letter, we will analyze different LO signal generators and develop a practical way of computation to decide how to choose the best configuration under minimum degradation of signal-to-noise ratio (SNR) at the output. 相似文献
5.
Temperature-dependent diffusion coefficient of soluble substances during ethanol extraction of clove
San Myint Wan Ramli Wan Daud Abu Bakar Mohamad Abdul Amir H. Kadhum 《Journal of the American Oil Chemists' Society》1996,73(5):603-610
The temperature dependence of the diffusion coefficient of ethanol-soluble substances from ground cloves (particle size 250
μm) during extraction was estimated by fitting batch extraction data at several temperatures (27.8, 40, 50, and 60°C) to a
previously developed mass transfer model. The model was based on spherical geometry of particles. Nonlinear regression analysis
was used to develop an equation that describes the diffusivity as a function of temperature. The temperature dependence ofD
A
was of the Arrhenius type. 相似文献
6.
Polypropylene (PP) hybrid composites have been produced by compounding two types of mineral fillers, viz., talc and kaolin with PP copolymer using a twin screw extruder. The PP hybrid composite was injection‐molded into dumbbell specimen for tensile, flexural, and impact properties characterizations. MFI and SEM studies were used to characterize the flow and morphological properties of the PP hybrid composites. The result shows that most of the hybrid composites showed a significant decrease in flow, tensile, flexural, and impact properties compared with the single filler‐filled PP composites. However, a hybridization effect was seen for the PPT20K10 hybrid composites, through the synergistic coalescence of positive characteristics from 20 wt % of talc and 10 wt % of kaolin. This hybrid formulation have given an economically advantageous material with the mechanical properties (tensile, flexural, and impact) comparable to those of the talc‐filled PP composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 434–441, 2007 相似文献
7.
M.H. El-Naas F. Abu Al-Rub I. Ashour M. Al Marzouqi 《Chemical Engineering and Processing: Process Intensification》2007,46(12):1391-1399
Batch experiments were carried out to asses the effect of Cu(II) and Zn(II) on the biosorption of lead(II) ions by non-living Chlorella vulgaris. The uptake of Pb(II) was examined for single, binary and ternary solutions at different initial concentrations and different pH values. The experimental results showed that the uptake increased with increasing pH from 3.0 to an optimum value of 5.0. The biosorption of Pb(II) was found to be adversely affected by the presence of Cu(II) ions, while Zn(II) ions seemed to have negligible effect on the process. The equilibrium data were fitted to four isotherm models: Langmuir, Freundlich, Sips and Dubinin–Radushkevich; the Sips isotherm gave the best fit for the data. Modeling of the controlling mechanisms indicated that both intrinsic kinetics and mass transfer played major roles in controlling the process. A new dimensionless parameter, Ψ, was defined to asses the relative contributions of the two mechanisms to the biosorption of lead(II). Mass transfer seemed to be the dominant mechanism at low initial lead(II) concentrations, while intrinsic kinetics dominates at high concentrations. 相似文献
8.
Mohammad Mizanur Rahman Md. Hasan Zahir Md. Eyasin Arafat Mohammad Abu Jafar Mazumder Rami Suleiman A. Madhan Kumar 《应用聚合物科学杂志》2021,138(9):49904
A waste material called oil fly ash (OFA) was acid-functionalized, yielding f-OFA-COOH, which was then reacted with cerium oxide (CeO2) to make CeO2-functionalized OFA, or f-OFA-CeO2. Pristine OFA and f-OFA-CeO2 were used to make waterborne polyurethane (WBPU) dispersions, referred to as WBPU/OFA and WBPU/f-OFA-CeO2, respectively, with defined OFA and f-OFA-CeO2 content. All the dispersions were applied to mild steel as organic coatings to evaluate their protective properties, such as their hydrophobicity, adhesive strength and UV-shielding resistance. These protective properties varied based on the OFA and f-OFA-CeO2 content. The highest water contact angle, minimum water swelling and maximum adhesive strength were found using WBPU/f-OFA-CeO2-20 coating (using 2.00 wt% f-OFA-CeO2), which also showed the maximum ultraviolet (UV) absorption via UV–vis spectroscopy analysis. This UV shielding result also matched field test results, as that coating was found to exhibit the lowest UV degradation near a marine atmosphere, as shown by X-ray photoelectron spectroscopy (XPS) analysis. The least affected hydrophobicity was also recorded for the sample with the WBPU/f-OFA-CeO2-20 coating. 相似文献
9.
10.
In recent years, we have witnessed a growing interest in the synchronous collaboration based class of applications. Several
techniques for collaborative virtual environments (CVE), haptic, audio and visual environments (C-HAVE) have been designed.
However, several challenging issues remain to be resolved before CVE and C-HAVE become a common place. In this paper, we focus
on applications that are based on closely coupled and highly synchronized haptic tasks that require a high-level of coordination
among the participants. Four main protocols have been designed to resolve the synchronization issues in such environments:
the synchronous collaboration transport protocol, the selective reliable transmission protocol, the reliable multicast transport
protocol and the scalable reliable multicast. While these four protocols have shown good performance for CVE and C-HAVE class
of applications, none of these protocols has been able to meet all of the basic CVE requirements, i.e., scalability, reliability,
synchronization, and minimum delay. In this paper, we present a hybrid protocol that is able to satisfy all of the CVE and
C-HAVE requirements and discuss its implementation and results in two tele-surgery applications.
This work is partially supported by Grants from Canada Research Chair Program, NSERC, OIT/Ontario Distinguished Researcher
Award, Early Research Award and ORNEC Research Grant. 相似文献