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The third-generation partnership project (3GPP) and 3GPP2 have standardized the IP multimedia subsystem (IMS) to provide ubiquitous and access network-independent IP-based services for next-generation networks via merging cellular...
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The third-generation partnership project (3GPP) and 3GPP2 have standardized the IP multimedia subsystem (IMS) to provide ubiquitous and access network-independent IP-based services for next-generation networks via merging cellular networks and the Internet. The application layer Session Initiation Protocol (SIP), standardized by 3GPP and 3GPP2 for IMS, is responsible for IMS session establishment, management, and transformation. The IEEE 802.16 worldwide interoperability for microwave access (WiMax) promises to provide high data rate broadband wireless access services. In this paper, we propose two novel interworking architectures to integrate WiMax and third-generation (3G) networks. Moreover, we analyze the SIP-based IMS registration and session setup signaling delay for 3G and WiMax networks with specific reference to their interworking architectures. Finally, we explore the effects of different WiMax-3G interworking architectures on the IMS registration and session setup signaling delay.
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Inexpensive cameras, different acquisition devices and mobile phones have resulted in the production of digital images in all spheres of life. There is common of these images for extracting useful information in many fields to per...
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Inexpensive cameras, different acquisition devices and mobile phones have resulted in the production of digital images in all spheres of life. There is common of these images for extracting useful information in many fields to perform image analysis and interpretation. One of the problems being faced in the use of this information is the presence of random valued impulse noise. Impulse noise removal is a crucial step in computer vision. Many articles have been published to remove or suppress impulse noise from grayscale digital images using different approaches. Edges and details are, however, often lost during the restoration of digital images. In this research, a two-stage approach for edge detection, preservation, and impulse noise removal is proposed. An effective statistics rank ordered absolute difference (ROAD) is used in the first stage to detect noisy pixels. Trimmed global mean (TGM) with adaptive window is employed later for the filtering process. With the combination of these processes in the proposed method, a higher quality image is restored and thus becomes more suitable for extracting the desired information. Comparison with many state-of-the-art methodologies indicates that the proposed method is effective in the detection of corrupted pixels and the restoration of images.
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Four new organotin (IV) complexes with general formula R3SnL/R2SnL2, where R = CH3, n-C4H9, C6H5 and L = Levofloxacin, were synthesized and characterized by elemental analyses, FT-IR and NMR (H-1 and C-13) spectroscopy. Spectrosco...
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Four new organotin (IV) complexes with general formula R3SnL/R2SnL2, where R = CH3, n-C4H9, C6H5 and L = Levofloxacin, were synthesized and characterized by elemental analyses, FT-IR and NMR (H-1 and C-13) spectroscopy. Spectroscopic data suggested a six-coordinated geometry for diorganotin(IV) derivatives and a five-coordinated geometry for triorganotin(IV) derivatives. The value of Me-Sn-Me bond angle for di- and trimethyltin complexes using the Lockhart equation, were 150 degrees and 116 degrees, respectively, that corresponded to six and five-coordinate geometry, accordingly. The ligand and its complexes were screened for their antibacterial, antifungal, cytotoxic, and free radical scavenging (DPPH) antioxidant activities. The biological data indicated those as potentially bioactive in each field of the study. Accumulated data of DNA interaction with the synthesized complexes based on UV-Vis, cyclic voltammetry and viscometry suggested an intercalative mode of the interaction.
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Four Pd(II) complexes of general formula [Pd(L-1)(2)(L-2)(2)], where L-1 = pyridine-2(1H)-thione, pyrimidine-2(1H)-thione, pyridine-4(1H)-thione, and pyridine-4(1H)-thione, L-2 = tri-p-tolylphosphine, have been synthesized by dire...
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Four Pd(II) complexes of general formula [Pd(L-1)(2)(L-2)(2)], where L-1 = pyridine-2(1H)-thione, pyrimidine-2(1H)-thione, pyridine-4(1H)-thione, and pyridine-4(1H)-thione, L-2 = tri-p-tolylphosphine, have been synthesized by direct reaction of K-2[PdCl4] with phosphine and heterocyclic thiones ligands in 1 : 2 : 2 molar ratio. The complexes have been characterized by elemental analyses, FT-IR and multinuclear NMR spectroscopy. The complexes 1 and 2 were also characterized by single crystal X-ray diffraction which revealed that the Pd(II) atom adopted a nearly square planar geometry with two tri-p-tolyphosphine molecules bound in a trans fashion and also two pyridine-2(1H)-thione (1) or pyrimidine-2(1H)-thione (2) molecules trans to each other. The compounds were tested for antibacterial activity, DNA interaction by brine shrimp lethality bioassay, antitumor activity, and gel electrophoresis. The complexes demonstrated moderate activity against gram positive and gram negative bacterial strains in comparison with a standard drug imipenum. Their antitumor activity against MCF7 tumor cell line was determined to be comparable to that of doxorubicin. The investigated compounds demonstrated no cytotoxic effect in brine shrimp bioassay study.
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A steady boundary layer flow and heat transfer over a radially stretching isothermal porous sheet is analyzed. Stretching is assumed to follow a radial power law, and the fluid is electrically conducting in the presence of a trans...
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A steady boundary layer flow and heat transfer over a radially stretching isothermal porous sheet is analyzed. Stretching is assumed to follow a radial power law, and the fluid is electrically conducting in the presence of a transverse magnetic field with a very small magnetic Reynolds number. The governing nonlinear partial differential equations are reduced to a system of nonlinear ordinary differential equations by using appropriate similarity transformations, which are solved analytically by the homotopy analysis method (HAM) and numerically by employing the shooting method with the adaptive Runge-Kutta method and Broyden's method in the domain [0,a). Analytical expressions for the velocity and temperature fields are derived. The influence of pertinent parameters on the velocity and temperature profiles is discussed in detail. The skin friction coefficient and the local Nusselt number are calculated as functions of several influential parameters. The results predicted by both methods are demonstrated to be in excellent agreement. Moreover, HAM results for a particular problem are also compared with exact solutions.
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Technological advancements in the silicon industry, as predicted by Moore's law, have enabled integration of billions of transistors on a single chip. To exploit this high transistor density for high performance, embedded systems ...
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Technological advancements in the silicon industry, as predicted by Moore's law, have enabled integration of billions of transistors on a single chip. To exploit this high transistor density for high performance, embedded systems are undergoing a transition from single-core to multi-core. Although a majority of embedded wireless sensor networks (EWSNs) consist of single-core embedded sensor nodes, multi-core embedded sensor nodes are envisioned to burgeon in selected application domains that require complex in-network processing of the sensed data. In this paper, we propose an architecture for heterogeneous hierarchical multi-core embedded wireless sensor networks (MCEWSNs) as well as an architecture for multi-core embedded sensor nodes used in MCEWSNs. We elaborate several compute-intensive tasks performed by sensor networks and application domains that would especially benefit from multi-core embedded sensor nodes. This paper also investigates the feasibility of two multi-core architectural paradigms—symmetric multiprocessors (SMPs) and tiled many-core architectures (TMAs)—for MCEWSNs. We compare and analyze the performance of an SMP (an Intel-based SMP) and a TMA (Tilera's TILEPro64) based on a parallelized information fusion application for various performance metrics (e.g., runtime, speedup, efficiency, cost, and performance per watt). Results reveal that TMAs exploit data locality effectively and are more suitable for MCEWSN applications that require integer manipulation of sensor data, such as information fusion, and have little or no communication between the parallelized tasks. To demonstrate the practical relevance of MCEWSNs, this paper also discusses several state-of-the-art multi-core embedded sensor node prototypes developed in academia and industry. We further discuss research challenges and future research directions for MCEWSNs.
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Essential oils have been used throughout the world in foods, fragrances, perfumery, cosmetics, and medicines and these oils are very expensive. The study was initiated to develop an on-farm solar distillation system for functional...
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Essential oils have been used throughout the world in foods, fragrances, perfumery, cosmetics, and medicines and these oils are very expensive. The study was initiated to develop an on-farm solar distillation system for functional, environmental and economic reasons. A Scheffler fixed focus concentrator is used for the solar distillation system. The system comprises a primary reflector (8 m2 area), secondary reflector, distillation still, condenser and Florentine flasks. The primary reflector rotates along an axis parallel to the earth's axis of rotation with the help of a precise photovoltaic tracking device and keeps the reflected beam aligned with the fixed secondary reflector as the sun moves. The secondary reflector further reflects the beam to target the bottom of the distillation still. The paper presents the development, evaluation and experimental results of the solar distillation system. The temperature at the focus was recorded as between 300 and 400 degrees C for beam radiation in the range 700-800 W m-2. The average power and efficiency of the solar distillation system were found to be 1.548 kW and 33.21% respectively. Different medicinal and aromatic plants like Melissa, peppermint, rosemary, cumin, and cloves etc. were processed successfully by using the solar distillation system and their process curves were drawn
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Essential oils have been used throughout the world in foods, fragrances, perfumery, cosmetics, and medicines and these oils are very expensive. The study was initiated to develop an on-farm solar distillation system for functional...
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Essential oils have been used throughout the world in foods, fragrances, perfumery, cosmetics, and medicines and these oils are very expensive. The study was initiated to develop an on-farm solar distillation system for functional, environmental and economic reasons. A Scheffler fixed focus concentrator is used for the solar distillation system. The system comprises a primary reflector (8 m2 area), secondary reflector, distillation still, condenser and Florentine flasks. The primary reflector rotates along an axis parallel to the earth's axis of rotation with the help of a precise photovoltaic tracking device and keeps the reflected beam aligned with the fixed secondary reflector as the sun moves. The secondary reflector further reflects the beam to target the bottom of the distillation still. The paper presents the development, evaluation and experimental results of the solar distillation system. The temperature at the focus was recorded as between 300 and 400 degrees C for beam radiation in the range 700-800 W m-2. The average power and efficiency of the solar distillation system were found to be 1.548 kW and 33.21% respectively. Different medicinal and aromatic plants like Melissa, peppermint, rosemary, cumin, and cloves etc. were processed successfully by using the solar distillation system and their process curves were drawn
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Aim To assess and correlate three distinct states of severely painful endodontically derived inflammation with their depiction on periapical radiographs using periapical index (PAI) scores. Methodology During a period of 15 months...
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Aim To assess and correlate three distinct states of severely painful endodontically derived inflammation with their depiction on periapical radiographs using periapical index (PAI) scores. Methodology During a period of 15 months, 368 consecutively enrolled patients with suspected endodontic emergency conditions were examined at the University of Zurich, Center of Dental Medicine. Cases with a severely painful (numeric rating scale, NRS-11 > 6) endodontically involved tooth and a clear pulpal and apical diagnosis (n = 162) were selected (one tooth per patient). Teeth were divided into three groups according to the clinically diagnosed main location of the inflammatory process: level 1: pulp (positive response to cold test), level 2: periodontium (no response to cold without swelling) and level 3: periapical tissues (no response to cold with swelling). Periapical radiographs were obtained using a digital unit and analysed by two calibrated observers. For level 2, which had the highest PAI variance (n = 76), the PAI scores were further scrutinized regarding their dependence on tooth location and the duration of pain. Data were analysed using chi-squared and non-parametric tests, alpha = 0.05. Results Overall, the PAI scores correlated well with the clinically diagnosed main location of periapical inflammation (Spearman's rho = 0.5131,P < 0.001), with level 1 having the lowest scores by far (P < 0.001) and level 2 having significantly lower scores compared to level 3 (P < 0.05). However, a PAI score of 5 was found in merely 3 teeth within the entire cohort, and 49% of the teeth in the level 2 group had no radiolucency (PAI < 3). Within level 2, the PAI scores were not dependent on tooth location but were substantially (P < 0.001) higher for teeth which had hurt for more than one week, and for root filled teeth. Conclusions For the analysed, severely painful endodontically involved teeth, the clinically diagnosed main location of inflammation was reflected by the periapical index. PAI scores were not significantly influenced by anatomical noise, yet in some cases under-estimated the clinical situation.
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A series of palladium(II) complexes with N, N-dimethylthiourea and phosphines [tri-p-tolylphosphine (Tptp), benzyl(diphenyl) phosphine (Bdp), cyclohexyl(diphenyl) phosphine (Cdp)] were synthesized by the direct reaction of K-2[(Pd...
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A series of palladium(II) complexes with N, N-dimethylthiourea and phosphines [tri-p-tolylphosphine (Tptp), benzyl(diphenyl) phosphine (Bdp), cyclohexyl(diphenyl) phosphine (Cdp)] were synthesized by the direct reaction of K-2[(PdCl4)] with the corresponding phosphines and then with N, N-dimethylthiourea at a molar ratio of 1 : 2 : 2. The general formula of these complexes is [Pd(L-1)(2)(L-2)(2)] Cl-2, where L-1 = N, N-dimethyl-thiourea (Dmtu), L-2 = Tptp, Bdp, Cdp. The complexes were characterized by elemental analyses, multinuclear NMR (H-1, C-13, P-31), and FT-IR. The complex with cyclohexyl(diphenyl) phosphine was also characterized by single crystal X-ray analysis. The spectral and crystallographic data suggest monodentate coordination of dimethylthiourea through the sulfur atom and of the phosphine ligand through the phosphorus atom and distorted square planar environment of palladium(II). The synthesized complexes have been screened for DNA-binding, antibacterial, cytotoxic, and antitumor activities. The complexes show interaction with DNA via intercalative mode. The complexes show good activity against both gram positive and gram negative bacteria as compared to that of a standard drug, Imipenem. Their antitumor activity against MCF7 tumor cell line was found to be comparable with doxorubicin. MTT assay was used to investigate the cytotoxicity of the studied compounds having activity order: 3 > 2 > 1.
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