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31.
The development complexity of Distributed Embedded Real-Time Systems (DERTS) can be reduced by the use of Service-Oriented Computing (SOC). However, the existing modeling methods allow modeling of either DERTS or SOC concepts and there is a lack of meta-model for Service-Oriented development of DERTS. This paper proposes a service-based meta-model for DERTS, along with the constraints of the elements of the meta-model. A Smart Home case study was designed to validate the meta-model. This meta-model could not only be beneficial for Service-Oriented development of DERTS, but can also be used at the Platform Independent Model (PIM) level of MDD.  相似文献   
32.
Transdermal patches loaded with ramipril and repaglinide were prepared with the ambition to develop matrix-type transdermal drug delivery system for enhanced permeability and hence improved bioavailability. Different formulations were designed by intermittent concentrations of hydroxypropyl methylcellulose K4M as hydrophilic polymer and ethyl cellulose as hydrophobic polymer. Solvent casting method was used for the fabrication of transdermal patches. Oleic acid and propylene glycol were used to enhance permeability along with polyethylene glycol 400 as plasticizer. Newly designed patches were then evaluated for various physicochemical and mechanical properties. Compatibility studies were performed by Fourier transformed infrared spectroscopy which did not reveal any interaction between drug and polymers. Crystalline nature of drugs was confirmed when they were subjected to X-ray diffraction study and surface morphological studies using scanning electron microscopy. Transdermal patches were of good mechanical strength with folding endurance of more than 300-fold and 100% flatness. Percent drug contents of ramipril and repaglinide ranged from 90 to 105%, i.e., analogous to official limits. In vitro and ex vivo permeation studies were executed using franz diffusion cell. The cumulative amount of drug permeated through skin was 55.22–112.72% for repaglinide and 73.14–91.46% for ramipril. The release behavior of the permeated drug was analyzed by the application of model-dependent approaches. The results showed that Korsmeyer–Peppas model was found to be dominating in most of the formulations and drugs followed diffusion mechanism. It could be concluded that hydroxypropyl methylcellulose K4M and ethyl cellulose has great potential for ramipril and repaglinide as a vector for transdermal drug delivery effectively because of the formation of smooth surfaces of patches, high folding endurance, and entrapment efficiency with the ability to release the drugs in sustained manner.  相似文献   
33.
The mixed convection of power-law fluids along a wedge in a porous medium is investigated numerically using an implicit finite difference method. Robin boundary condition is applied at the wedge surface. To explore the effects of mixed convection, both forced and free convection dominated regimes are considered separately. Non-similarity solutions are obtained for the variable heat transfer coefficient. Local dimensionless skin friction and Nusselt number are presented in tabular and graphical forms for the selected values of wedge and convective parameters. The wedge angle geometry parameter r m, power index of pseudoplastic fluids n and mixed convection parameter ξ range from 0 to 1 in both regimes, whereas different values of convective parameter h c are considered for investigating the behavior of skin friction and heat transfer rates.  相似文献   
34.
This paper presents a new methodology in form of three sequencing techniques for the development of alternative quarry plans using cement quarry production-sequencing algorithm. The algorithm generates multi-period quarry plans, satisfying geometric (slope) and cement plant production capacity constraints. The benefits of the approach are demonstrated through application on an existing cement manufacturing operation in Midwestern USA. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 103–114, March–April, 2008.  相似文献   
35.
In the present study, an attempt is made to enhance the performance of heat pump by utilizing two types of nanofluids namely, copper and alumina nanofluids. These nanofluids were employed around the evaporator coil of the heat pump. The nanofluids were used to enhance the heat input to the system by means of providing an external jacket around the evaporator coil. Both the nanofluids were prepared in three volume fractions 1%, 2% and 5%. Water was chosen as the base fluid. The performance of the heat pump was assessed by calculating the coefficient of performance of the system when it was operated with and without nanofluid jacket. A significant enhancement in the coefficient of performance was noticed when copper and alumina nanofluids were employed in the system. Also, the coefficient of performance was found to have a direct relationship with the tested volume fractions. For the highest volume fraction of 5%, the performance of the heat pump was found to enhance by 23% with alumina nanofluid, while for copper nanofluid, a very significant enhancement in performance by 72% was observed. Thus, utilizing of nanofluids in heat pumps can be very beneficial towards performance enhancement and the idea can also be extended to other thermal systems such as steam power plant, automobile radiator, industrial heat exchangers and refrigeration systems.  相似文献   
36.
Designing accelerators for the real-time computation of Fast Fourier Transform (FFT) algorithms for state-of-the-art Orthogonal Frequency-Division Multiplexing (OFDM) demodulators has always been challenging. We have scaled-up a template-based Coarse-Grain Reconfigurable Array device for faster FFT processing that generates special purpose accelerators based on the user input. Using a basic and a scaled-up version, we have generated a radix-4 and mixed-radix (2, 4) FFT accelerator to process different length and types of algorithms. Our implementation results show that these accelerators satisfy not only the execution time requirements of FFT processing for Single Input Single Output (SISO) wireless standards that are IEEE-802.11 a/g and 3GPP-LTE but also for Multiple Input Multiple Output (MIMO) IEEE-802.11n standard.  相似文献   
37.
Several toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2) to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated that okadaic acid has induced the translocation of ERp57 to the cellular membrane.  相似文献   
38.
The paper presents an entropy generation analysis for steady conduction in a slab with temperature‐dependent volumetric internal heat generation. The slab experiences asymmetric convective cooling on its two faces. The exact analytical solution for the temperature distribution is used to compute dimensionless local and total entropy generation rates in the slab. The total entropy generation rate depends on five dimensionless parameters: reference heat generation temperature Q, the heat generation–temperature variation parameter a, the temperature asymmetry parameter λ, and Biot numbers Bi1 and Bi2. Graphs illustrating the effect of these five parameters on the local and total entropy generation rates are presented and discussed. It is found that the total entropy generation in the slab can be minimized with a suitable choice of the cooling parameters. The paper corrects the flawed entropy results published recently. The present results for the special case of uniform internal heat generation confirm the results presented in a 2003 paper. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20404  相似文献   
39.
A numerical analysis is carried out to study the performance of natural convection inside a square open tilted cavity filled with air. An adiabatic circular solid cylinder is placed at the center of the cavity and the sidewall in front of the breathing space is heated by a constant heat flux. The top and bottom walls are kept at the ambient constant temperature. Two‐dimensional forms of Navier–Stokes equations along with the energy equations are solved using the Galerkin finite element method. Results are obtained for a range of Grashof numbers from 103 to 106 at Pr = 0.71 while the tilt angle varies from 0 to 45° and the diameter ratio of the cylinder is considered to be 0.2, 0.3, and 0.4 with constant physical properties. The parametric studies for a wide range of cylinder diameter ratios and cavity tilt angles show significant features of the present problem in terms of stream functions and temperature profiles. The computational results indicate that the heat transfer coefficient is strongly influenced by the above governing parameters. It is also found that the average Nusselt number decreases when the diameter ratio increases. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21001  相似文献   
40.
This paper shows that the set of rational, strictly proper, robustly stabilizing controllers for single‐input single‐output linear‐time invariant plants will form a bounded (can even be empty) set in the controller parameter space if and only if the order of the stabilizing controller cannot be reduced any further; if the set of proper stabilizing controllers of order r is not empty and the set of strictly proper controllers of order r is bounded, then r is the minimal order of stabilization. The paper also extends this result to characterize the set of controllers that guarantee some pre‐specified performance specifications. In particular, it is shown here that the minimal order of a controller that guarantees specified performance is l iff (1) there is a controller of order l guaranteeing the specified performance and (2) the set of strictly proper, robustly stabilizing controllers of order l and guaranteeing the performance is bounded. Moreover, if the order of the controller is increased, the set of higher‐order controllers which satisfies the specified performance will necessarily be unbounded. This characterization is provided for performance specifications, such as gain margin and robust stability, which require a one‐parameter family of real polynomials to be Hurwitz, where the parameter is in a closed interval. Other performance specifications, such as phase margin and ℋ︁ norm, can be reduced to the problem of determining a set of stabilizing controllers that renders a family of complex polynomials Hurwitz. The characterization of the set of controllers for the stabilization of complex polynomials is provided and is used to show the boundedness properties for the set of controllers that guarantee a given phase margin or an upper bound on the ℋ︁ norm. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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