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Storage Space (storage + space)
Selected AbstractsA new mutual authentication and key exchange protocol with balanced computational power for wireless settingsEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 2 2004Chou-Chen Yang Mutual authentication and key exchange protocols (MAKEP) provide two parties in communication with guarantee of true identity. And then the two parties end up sharing a common session key for privacy and data integrity during the session. In MAKEP, public-key-based schemes and symmetric-key-based schemes are often used. However, the former requires high computation complexity and hence, it is not suitable for applications in wireless settings. The latter has to maintain many distinct keys for different parties. Wong et al. proposed the Linear MAKEP to solve these problems. But in term of storage space, it is not optimal. In this paper, we propose a scheme that uses the geometric properties of line to achieve mutual authentication and key exchange. Compared with Wong et al.'s scheme, our scheme is efficient and requires less storage space. It can withstand the replay attack and the unknown key-share attack, and the server does not bear much more computation cost than the client in each session, hence we call it a protocal with balanced computational power. Copyright © 2004 AEI [source] ParCYCLIC: finite element modelling of earthquake liquefaction response on parallel computersINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 12 2004Jun Peng Abstract This paper presents the computational procedures and solution strategy employed in ParCYCLIC, a parallel non-linear finite element program developed based on an existing serial code CYCLIC for the analysis of cyclic seismically-induced liquefaction problems. In ParCYCLIC, finite elements are employed within an incremental plasticity, coupled solid,fluid formulation. A constitutive model developed for simulating liquefaction-induced deformations is a main component of this analysis framework. The elements of the computational strategy, designed for distributed-memory message-passing parallel computer systems, include: (a) an automatic domain decomposer to partition the finite element mesh; (b) nodal ordering strategies to minimize storage space for the matrix coefficients; (c) an efficient scheme for the allocation of sparse matrix coefficients among the processors; and (d) a parallel sparse direct solver. Application of ParCYCLIC to simulate 3-D geotechnical experimental models is demonstrated. The computational results show excellent parallel performance and scalability of ParCYCLIC on parallel computers with a large number of processors. Copyright © 2004 John Wiley & Sons, Ltd. [source] A forward-only recursion algorithm for MAP decoding of linear block codesINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 8 2002Hans-Jürgen Zepernick Abstract The evolution of digital mobile communications along with the increase of integrated circuit complexity has resulted in frequent use of error control coding to protect information against transmission errors. Soft decision decoding offers better error performance compared to hard decision decoding but on the expense of decoding complexity. The maximum a posteriori (MAP) decoder is a decoding algorithm which processes soft information and aims at minimizing bit error probability. In this paper, a matrix approach is presented which analytically describes MAP decoding of linear block codes in an original domain and a corresponding spectral domain. The trellis-based decoding approach belongs to the class of forward-only recursion algorithms. It is applicable to high rate block codes with a moderate number of parity bits and allows a simple implementation in the spectral domain in terms of storage requirements and computational complexity. Especially, the required storage space can be significantly reduced compared to conventional BCJR-based decoding algorithms. Copyright © 2002 John Wiley & Sons, Ltd. [source] Architecture design, performance analysis and VLSI implementation of a reconfigurable shared buffer for high-speed switch/router,INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 2 2009Ling Wu Abstract Modern switches and routers require massive storage space to buffer packets. This becomes more significant as link speed increases and switch size grows. From the memory technology perspective, while DRAM is a good choice to meet capacity requirement, the access time causes problems for high-speed applications. On the other hand, though SRAM is faster, it is more costly and does not have high storage density. The SRAM/DRAM hybrid architecture provides a good solution to meet both capacity and speed requirements. From the switch design and network traffic perspective, to minimize packet loss, the buffering space allocated for each switch port is normally based on the worst-case scenario, which is usually huge. However, under normal traffic load conditions, the buffer utilization for such configuration is very low. Therefore, we propose a reconfigurable buffer-sharing scheme that can dynamically adjust the buffering space for each port according to the traffic patterns and buffer saturation status. The target is to achieve high performance and improve buffer utilization, while not posing much constraint on the buffer speed. In this paper, we study the performance of the proposed buffer-sharing scheme by both a numerical model and extensive simulations under uniform and non-uniform traffic conditions. We also present the architecture design and VLSI implementation of the proposed reconfigurable shared buffer using the 0.18 µm CMOS technology. Our results manifest that the proposed architecture can always achieve high performance and provide much flexibility for the high-speed packet switches to adapt to various traffic patterns. Furthermore, it can be easily integrated into the functionality of port controllers of modern switches and routers. Copyright © 2008 John Wiley & Sons, Ltd. [source] Implementation solutions for the interworking between MMS and streamingINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 10 2003Miraj-E-Mostafa Abstract Multimedia messaging service (MMS) and streaming are forerunner multimedia applications in mobile communication. Use of streaming in the retrieval of continuous multimedia content of MMS is the identified optimum scope (extent) of interworking between MMS and streaming. The optimum interworking can remove a limitation visible in MMS,retrieving content requiring more storage space than available in a mobile terminal. This paper presents two different solutions for implementing the interworking. The implementation solutions are consistent with the existing mobile frameworks and the working principles and procedures of both MMS and streaming. Consistency is very important here not only to avoid creating isolated solution, but also to preserve user experience. This paper describes in detail how each of the solutions operates, including the process of using streaming in the MMS retrieval. Pros and cons of both the solutions are also analysed to compare those. Other important factors tackled in the analysis are implementation flexibility, complexity, terminal capability indication, and content adaptation. Copyright © 2003 John Wiley & Sons, Ltd. [source] Automated separation of cord blood units in top and bottom bags using the Compomat G4INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2006P. SOLVES Summary Cord blood (CB) has become a real alternative source of haematopoietic stem cells for bone marrow reconstitution in a variety of malignant disorders. As a response to this increasing activity, CB banks have been developed to guarantee the quality of processed CB units. Volume reduction of CB units maximizes storage space and also has other advantages. The aim of this study was to develop a program for the volume reduction of CB in the Compomat G4 device. We also compared two different top and bottom systems for CB fractionation (Compomat G4 and Optipress II). We empirically designed three different programs for volume reduction of CB with Compomat G4: two for final BC volume of 41 ml (CB1 and CB2) and the other one for buffy coat (BC) volume of 25 ml (CB3). Significantly worse recoveries were achieved for CB processed with program CB3. A RBC depletion of ,50%, ,60% and ,70% were achieved for 67%, 39% and 9% of all units respectively. When comparing Compomat G4 and Optipress II, total nucleated cell recovery was similar for both methods, while lymphocytes recovery was significantly better for Optipress II. [source] Robust adaptive fuzzy controller for non-affine nonlinear systems with dynamic rule activationINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 2 2003Jang-Hyun Park Abstract This paper describes the design of a robust adaptive fuzzy controller for an uncertain single-input single-output nonlinear dynamical systems. While most recent results on fuzzy controllers considers affine systems with fixed rule-base fuzzy systems, we propose a control scheme for non-affine nonlinear systems and a dynamic fuzzy rule activation scheme in which an appropriate number of the fuzzy rules are chosen on-line. By using the proposed scheme, we can reduce the computation time, storage space, and dynamic order of the adaptive fuzzy system without significant performance degradation. The Lyapunov synthesis approach is used to guarantee a uniform ultimate boundedness property for the tracking error, as well as for all other signals in the closed loop. No a priori knowledge of an upper bounds on the uncertainties is required. The theoretical results are illustrated through a simulation example. Copyright © 2002 John Wiley & Sons, Ltd. [source] A portable system for continuous monitoring of bird nests using digital video recordersJOURNAL OF FIELD ORNITHOLOGY, Issue 3 2007Andrew J. Pierce ABSTRACT A variety of photographic methods have been described for monitoring nest predation. All have limitations for studying active nests in remote situations, such as size, expense, volume of data recorded, and types of trigger mechanisms. We developed a digital video surveillance system using infrared cameras to monitor predation at bird nests. The main advantage of this system over other video recorders is the small size of the recorder that can run continuously at 29 frames/s for more than 3 days. The recorder's built-in monitor makes it more transportable and allows for easy setup. Digital data is compact, can be reviewed quickly, and requires less physical storage space than videotapes. We recorded nest predation by mammals, birds, and snakes as well as egg and nestling losses not caused by predation. System failure rates were low and the total cost was comparable to ($700 US) video cassette recorders that are often used to monitor nests. SINOPSIS Se han descrito una gran variedad de métodos fotográficos para monitorear la depredación de nidos. Todos los métodos tienen limitaciones para estudiar nidos activos a distancia, como su tamaño, costo, volumen de los datos grabados y mecanismos para activar el equipo. Desarrollamos un sistema digital de vigilancia, utilizando cámaras infrarrojas para monitorear la depredación de nidos. La ventaja principal de este equipo sobre otros similares es el tamaño de la grabadora, la cual puede funcionar continuamente a 29 cuadros/s por más de tres días. El monitor integrado a la cámara hace que el equipo que sea más fácil de transportar y permite que se pueda montar con facilidad. Los datos digitales son compactos, se pueden revisar rápidamente, y requieren menos espacio de almacenaje que las cintas de video convencionales. Grabamos depredación de nidos por mamíferos, aves y culebras al igual que la pérdida de huevos y pichones por otras causas. La tasa de malfuncionamiento fue baja y el costo del equipo ($700 US) es comparable a otros equipos de videograbación a cassette que se utilizan frecuentemente para monitorear nidos. [source] Three-dimensional numerical simulation of injection molding filling of optical lens and multiscale geometry using finite element methodPOLYMER ENGINEERING & SCIENCE, Issue 9 2006Sang-Woo Kim This article presents the development, verification, and validation of three-dimensional (3-D) numerical simulation for injection molding filling of 3-D parts and parts with microsurface features. For purpose of verification and comparison, two numerical models, the mixed model and the equal-order model, were used to solve the Stokes equations with three different tetrahedral elements (Taylor-Hood, MINI, and equal-order). The control volume scheme with tetrahedral finite element mesh was used for tracking advancing melt fronts and the operator splitting method was selected to solve the energy equation. A new, simple memory management procedure was introduced to deal with the large sparse matrix system without using a huge amount of storage space. The numerical simulation was validated for mold filling of a 3-D optical lens. The numerical simulation agreed very well with the experimental results and was useful in suggesting a better processing condition. As a new application area, a two-step macro,micro filling approach was adopted for the filling analysis of a part with a micro-surface feature to handle both macro and micro dimensions while avoiding an excessive number of elements. POLYM. ENG. SCI., 46:1263,1274, 2006. © 2006 Society of Plastics Engineers [source] Fast pyrolysis technology developmentBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2010RH Venderbosch Abstract While the intention of slow pyrolysis is to produce mainly charcoal, fast pyrolysis is meant to convert biomass to a maximum quantity of liquids (bio-oil). Both processes have in common that the biomass feedstock is densified to reduce storage space and transport costs. A comfortable, more stable and cleaner intermediate energy carrier is obtained, which is much more uniform and well defined. In this review, the principles of fast pyrolysis are discussed, and the main technologies reviewed (demo scale: fluid bed, rotating cone and vacuum pyrolysis; pilot plant: ablative and twin screw pyrolysis). Possible product applications are discussed in relation to the bio-oil properties. General mass and energy balance are provided as well, together with some remarks on the economics. Challenges for the coming years are (1) improvement of the reliability of pyrolysis reactors and processes; (2) the demonstration of the oil's utilization in boilers, engines and turbines; and (3) the development of technologies for the production of chemicals and biofuels from pyrolysis oils. One important conclusion in relation to biofuel production is that the type of oxygen functionalities (viz. as an alcohol, ketone, aldehyde, ether, or ester) in the oil should be controlled, rather then merely focusing on a reduction of just the oxygen content itself. Copyright © 2010 Society of Chemical Industry and John Wiley & Sons, Ltd [source] Tectonic Fractures in Tight Gas Sandstones of the Upper Triassic Xujiahe Formation in the Western Sichuan Basin, ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 5 2010ZENG Lianbo Abstract: The western Sichuan Basin, which is located at the front of the Longmen Mountains in the west of Sichuan Province, China, is a foreland basin formed in the Late Triassic. The Upper Triassic Xujiahe Formation is a tight gas sandstone reservoir with low porosity and ultra-low permeability, whose gas accumulation and production are controlled by well-developed fracture zones. There are mainly three types of fractures developed in the Upper Triassic tight gas sandstones, namely tectonic fractures, diagenetic fractures and overpressure-related fractures, of which high-angle tectonic fractures are the most important. The tectonic fractures can be classified into four sets, i.e., N-S-, NE-, E-W- and NW-striking fractures. In addition, there are a number of approximately horizontal shear fractures in some of the medium-grained sandstones and grit stones nearby the thrusts or slip layers. Tectonic fractures were mainly formed at the end of the Triassic, the end of the Cretaceous and the end of the Neogene-Early Pleistocene. The development degree of tectonic fractures was controlled by lithology, thickness, structure, stress and fluid pressure. Overpressure makes not only the rock shear strength decrease, but also the stress state change from compression to tension. Thus, tensional fractures can be formed in fold-thrust belts. Tectonic fractures are mainly developed along the NE- and N-S-striking structural belts, and are the important storage space and the principal flow channels in the tight gas sandstone. The porosity of fractures here is 28.4% of the gross reservoir porosity, and the permeability of fractures being two or three grades higher than that of the matrix pores. Four sets of high-angle tectonic fractures and horizontal shear fractures formed a good network system and controlled the distribution and production of gas in the tight sandstones. [source] | ||||||||||||||||||||||