Optimization of Bit Plane Combination for Efficient Digital Image Watermarking
Kejgir, Sushma
2009-01-01
In view of the frequent multimedia data transfer authentication and protection of images has gained importance in todays world. In this paper we propose a new watermarking technique, based on bit plane, which enhances robustness and capacity of the watermark, as well as maintains transparency of the watermark and fidelity of the image. In the proposed technique, higher strength bit plane of digital signature watermark is embedded in to a significant bit plane of the original image. The combination of bit planes (image and watermark) selection is an important issue. Therefore, a mechanism is developed for appropriate bit plane selection. Ten different attacks are selected to test different alternatives. These attacks are given different weightings as appropriate to user requirement. A weighted correlation coefficient for retrieved watermark is estimated for each of the alternatives. Based on these estimated values optimal bit plane combination is identified for a given user requirement. The proposed method is ...
Directory of Open Access Journals (Sweden)
Rahmad Hidayat
2015-04-01
Full Text Available Bit-Plane Complexity Segmentation (BPCS is a fairly new steganography technique. The most important process in BPCS is the calculation of complexity value of a bit-plane. The bit-plane complexity is calculated by looking at the amount of bit changes contained in a bit-plane. If a bit-plane has a high complexity, the bi-plane is categorized as a noise bit-plane that does not contain valuable information on the image. Classification of the bit-plane using the set cripst set (noise/not is not fair, where a little difference of the value will significantly change the status of the bit-plane. The purpose of this study is to apply the principles of fuzzy sets to classify the bit-plane into three sets that are informative, partly informative, and the noise region. Classification of the bit-plane into a fuzzy set is expected to classify the bit-plane in a more objective approach and ultimately message capacity of the images can be improved by using the Mamdani fuzzy inference to take decisions which bit-plane will be replaced with a message based on the classification of bit-plane and the size of the message that will be inserted. This research is able to increase the capability of BPCS steganography techniques to insert a message in bit-pane with more precise so that the container image quality would be better. It can be seen that the PSNR value of original image and stego-image is only slightly different.
Efficient Face Recognition in Video by Bit Planes Slicing
Directory of Open Access Journals (Sweden)
Srinivasa R. Inbathini
2012-01-01
Full Text Available Problem statement: Video-based face recognition must be able to overcome the imaging interference such as pose and illumination. Approach: A model is designed to study for face recognition based on video sequence and also test image. In training stage, single frontal image is taken as a input to the recognition system. A new virtual image is generated using bit plane feature fusion to effectively reduce the sensitivity to illumination variances. A Self-PCA is performed to get each set of Eigen faces and to get projected image. In recognition stage, automatic face detection scheme is first applied to the video sequences. Frames are extracted from the video and virtual frame is created. Each bit plane of test face is extracted and then the feature fusion face is constructed, followed by the projection and reconstruction using each set of the corresponding Eigen faces. Results: This algorithm is compared with conventional PCA algorithm. The minimum error of reconstruction is calculated. If error is less than a threshold value, then it recognizes the face from the database. Conclusion: Bit plane slicing mechanism is applied in video based face recognition. Experimental results shows that its far more superior than conventional method under various pose and illumination condition.
Institute of Scientific and Technical Information of China (English)
刘虎; 袁海东
2012-01-01
Since Bit-Plane Complexity Segmentation ( BPCS) steganography is vulnerable to complex histogram attack, this paper proposed an improved algorithm based on preprocessing. The steganography derived compensatory rule from distribution of the cover image. Then it used reversed preprocessing in compensation to the change of complexity caused by embedded information. The experimental results show that the proposed algorithm can properly hide information and counteract the attack of complex histogram. The compensation happens before information hiding, so it can maintain the big capacity characteristic of the original algorithm.%位平面复杂度分割(BPCS)隐写易受复杂度直方图攻击,为了弥补这一缺陷,提出了一种基于预处理的改进隐写算法.算法针对载密图像进行统计特征的量化分析,求导出逆向预处理的补偿规则,进而对嵌入信息引起的复杂度变化进行逆向的预处理补偿.实验结果表明,改进的算法在保证隐蔽性的同时具有很好的抗复杂度直方图攻击的能力,由于补偿过程是在隐藏秘密信息之前发生的,算法也较好地保持了BPCS大容量隐写的优点.
Low complexity bit loading algorithm for OFDM system
Institute of Scientific and Technical Information of China (English)
Yang Yu; Sha Xuejun; Zhang Zhonghua
2006-01-01
A new approach to loading for orthogonal frequency division multiplexing (OFDM) system is proposed, this bit-loading algorithm assigns bits to different subchannels in order to minimize the transmit energy. In the algorithm,first most bit are allocated to each subchannels according to channel condition, Shannon formula and QoS require of the user, then the residual bit are allocated to the subchannels bit by bit. In this way the algorithm is efficient while calculation is less complex. This is the first time to load bits with the scale following Shannon formula and the algorithm is of O (4N) complexity.
A hyperspectral images compression algorithm based on 3D bit plane transform
Zhang, Lei; Xiang, Libin; Zhang, Sam; Quan, Shengxue
2010-10-01
According the analyses of the hyper-spectral images, a new compression algorithm based on 3-D bit plane transform is proposed. The spectral coefficient is higher than the spatial. The algorithm is proposed to overcome the shortcoming of 1-D bit plane transform for it can only reduce the correlation when the neighboring pixels have similar values. The algorithm calculates the horizontal, vertical and spectral bit plane transform sequentially. As the spectral bit plane transform, the algorithm can be easily realized by hardware. In addition, because the calculation and encoding of the transform matrix of each bit are independent, the algorithm can be realized by parallel computing model, which can improve the calculation efficiency and save the processing time greatly. The experimental results show that the proposed algorithm achieves improved compression performance. With a certain compression ratios, the algorithm satisfies requirements of hyper-spectral images compression system, by efficiently reducing the cost of computation and memory usage.
Robust Face Recognition using Voting by Bit-plane Images based on Sparse Representation
Directory of Open Access Journals (Sweden)
Dongmei Wei
2015-08-01
Full Text Available Plurality voting is widely employed as combination strategies in pattern recognition. As a technology proposed recently, sparse representation based classification codes the query image as a sparse linear combination of entire training images and classifies the query sample class by class exploiting the class representation error. In this paper, an improvement face recognition approach using sparse representation and plurality voting based on the binary bit-plane images is proposed. After being equalized, gray images are decomposed into eight bit-plane images, sparse representation based classification is exploited respectively on the five bit-plane images that have more discrimination information. Finally, the true identity of query image is voted by these five identities obtained. Experiment results shown that this proposed approach is preferable both in recognition accuracy and in recognition speed.
Schmanske, Brian M.; Loew, Murray H.
2003-05-01
A technique for assessing the impact of lossy wavelet-based image compression on signal detection tasks is presented. A medical image"s value is based on its ability to support clinical decisions such as detecting and diagnosing abnormalities. Image quality of compressed images is, however, often stated in terms of mathematical metrics such as mean square error. The presented technique provides a more suitable measure of image degradation by building on the channelized Hotelling observer model, which has been shown to predict human performance of signal detection tasks in noise-limited images. The technique first decomposes an image into its constituent wavelet subband coefficient bit-planes. Channel responses for the individual subband bit-planes are computed, combined,and processed with a Hotelling observer model to provide a measure of signal detectability versus compression ratio. This allows a user to determine how much compression can be tolerated before signal detectability drops below a certain threshold.
Sleep stage classification with low complexity and low bit rate.
Virkkala, Jussi; Värri, Alpo; Hasan, Joel; Himanen, Sari-Leena; Müller, Kiti
2009-01-01
Standard sleep stage classification is based on visual analysis of central (usually also frontal and occipital) EEG, two-channel EOG, and submental EMG signals. The process is complex, using multiple electrodes, and is usually based on relatively high (200-500 Hz) sampling rates. Also at least 12 bit analog to digital conversion is recommended (with 16 bit storage) resulting in total bit rate of at least 12.8 kbit/s. This is not a problem for in-house laboratory sleep studies, but in the case of online wireless self-applicable ambulatory sleep studies, lower complexity and lower bit rates are preferred. In this study we further developed earlier single channel facial EMG/EOG/EEG-based automatic sleep stage classification. An algorithm with a simple decision tree separated 30 s epochs into wakefulness, SREM, S1/S2 and SWS using 18-45 Hz beta power and 0.5-6 Hz amplitude. Improvements included low complexity recursive digital filtering. We also evaluated the effects of a reduced sampling rate, reduced number of quantization steps and reduced dynamic range on the sleep data of 132 training and 131 testing subjects. With the studied algorithm, it was possible to reduce the sampling rate to 50 Hz (having a low pass filter at 90 Hz), and the dynamic range to 244 microV, with an 8 bit resolution resulting in a bit rate of 0.4 kbit/s. Facial electrodes and a low bit rate enables the use of smaller devices for sleep stage classification in home environments.
Institute of Scientific and Technical Information of China (English)
XIONG ChengYi; TIAN JinWen; LIU Jian
2008-01-01
This paper introduced a novel high performance algorithm and VLSI architectures for achieving bit plane coding (BPC) in word level sequential and parallel mode. The proposed BPC algorithm adopts the techniques of coding pass prediction and par-allel & pipeline to reduce the number of accessing memory and to increase the ability of concurrently processing of the system, where all the coefficient bits of a code block could be coded by only one scan. A new parallel bit plane architecture (PA) was proposed to achieve word-level sequential coding. Moreover, an efficient high-speed architecture (HA) was presented to achieve multi-word parallel coding. Compared to the state of the art, the proposed PA could reduce the hardware cost more efficiently, though the throughput retains one coefficient coded per clock. While the proposed HA could perform coding for 4 coefficients belonging to a stripe column at one intra-clock cycle, so that coding for an N×N code-block could be completed in approximate N2/4 intra-clock cycles. Theoretical analysis and ex-perimental results demonstrate that the proposed designs have high throughput rate with good performance in terms of speedup to cost, which can be good alter-natives for low power applications.
Multispectral information hiding in RGB image using bit-plane-based watermarking and its application
Shinoda, Kazuma; Watanabe, Aya; Hasegawa, Madoka; Kato, Shigeo
2015-06-01
Although it was expected that multispectral images would be implemented in many applications, such as remote sensing and medical imaging, their use has not been widely diffused in these fields. The development of a compact multispectral camera and display will be needed for practical use, but the format compatibility between multispectral and RGB images is also important for reducing the introduction cost and having high usability. We propose a method of embedding the spectral information into an RGB image by watermarking. The RGB image is calculated from the multispectral image, and then, the original multispectral image is estimated from the RGB image using Wiener estimation. The residual data between the original and the estimated multispectral image are compressed and embedded in the lower bit planes of the RGB image. The experimental results show that, as compared with Wiener estimation, the proposed method leads to more than a 10 dB gain in the peak signal-to-noise ratio of the reconstructed multispectral image, while there are almost no significant perceptual differences in the watermarked RGB image.
Techniques to measure complex-plane fields
CSIR Research Space (South Africa)
Dudley, Angela L
2014-09-25
Full Text Available In this work we construct coherent superpositions of Gaussian and vortex modes which can be described to occupy the complex-plane. We demonstrate how these fields can be experimentally constructed in a digital, controllable manner with a spatial...
Not so Complex: Iteration in the Complex Plane
O'Dell, Robin S.
2014-01-01
The simple process of iteration can produce complex and beautiful figures. In this article, Robin O'Dell presents a set of tasks requiring students to use the geometric interpretation of complex number multiplication to construct linear iteration rules. When the outputs are plotted in the complex plane, the graphs trace pleasing designs…
Fpga Implementation of 8-Bit Vedic Multiplier by Using Complex Numbers
Directory of Open Access Journals (Sweden)
Gundlapalle Nandakishore,
2014-06-01
Full Text Available The paper describes the implementation of 8-bit vedic multiplier using complex numbers previous technique describes that 8-bit vedic multiplier using barrel shifter by FPGA implementation comparing the both technique in this paper propagation delay is reduced so that processing of speed will be high 8-bit vedic multiplier using barrel shifter propagation delay nearly 22nsec but present technique 8-bit vedic multiplier using complex numbers where propagation delay is 19nsec. The design is implemented and verified by FPGA and ISE simulator. The core was implemented on the Spartan 3E starts board the preferred language is used in verilog.
Hybrid Inflation in the Complex Plane
Buchmuller, Wilfried; Kamada, Kohei; Schmitz, Kai
2014-01-01
Supersymmetric hybrid inflation is an exquisite framework to connect inflationary cosmology to particle physics at the scale of grand unification. Ending in a phase transition associated with spontaneous symmetry breaking, it can naturally explain the generation of entropy, matter and dark matter. Coupling F-term hybrid inflation to soft supersymmetry breaking distorts the rotational invariance in the complex inflaton plane---an important fact, which has been neglected in all previous studies. Based on the delta-N formalism, we analyze the cosmological perturbations for the first time in the full two-field model, also taking into account the fast-roll dynamics at and after the end of inflation. As a consequence of the two-field nature of hybrid inflation, the predictions for the primordial fluctuations depend not only on the parameters of the Lagrangian, but are eventually fixed by the choice of the inflationary trajectory. Recognizing hybrid inflation as a two-field model resolves two shortcomings often time...
Hybrid inflation in the complex plane
Buchmüller, W.; Domcke, V.; Kamada, K.; Schmitz, K.
2014-07-01
Supersymmetric hybrid inflation is an exquisite framework to connect inflationary cosmology to particle physics at the scale of grand unification. Ending in a phase transition associated with spontaneous symmetry breaking, it can naturally explain the generation of entropy, matter and dark matter. Coupling F-term hybrid inflation to soft supersymmetry breaking distorts the rotational invariance in the complex inflaton plane — an important fact, which has been neglected in all previous studies. Based on the δ N formalism, we analyze the cosmological perturbations for the first time in the full two-field model, also taking into account the fast-roll dynamics at and after the end of inflation. As a consequence of the two-field nature of hybrid inflation, the predictions for the primordial fluctuations depend not only on the parameters of the Lagrangian, but are eventually fixed by the choice of the inflationary trajectory. Recognizing hybrid inflation as a two-field model resolves two shortcomings often times attributed to it: the fine-tuning problem of the initial conditions is greatly relaxed and a spectral index in accordance with the PLANCK data can be achieved in a large part of the parameter space without the aid of supergravity corrections. Our analysis can be easily generalized to other (including large-field) scenarios of inflation in which soft supersymmetry breaking transforms an initially single-field model into a multi-field model.
Plane Transformations in a Complex Setting II: Isometries
Dana-Picard, Thierry
2007-01-01
This paper is the second part of a study of plane transformations using a complex setting. The first part was devoted to homotheties and translations, now attention is turned towards plane isometries. The group theoretic properties of plane isometries are easy to derive and images of classical geometrical objects by these transformations are…
Plane Transformations in a Complex Setting I: Homotheties-Translations
Dana-Picard, T.
2006-01-01
A previous note described how complex numbers can be used for elementary analytic geometry in the plane, describing lines, circles and their intersections using complex Cartesian equations. In the present note, a description of elementary plane transformations, namely homotheties and translations, their group structure and their operations on…
Plane Transformations in a Complex Setting III: Similarities
Dana-Picard, Thierry
2009-01-01
This is the third part of a study of plane transformations described in a complex setting. After the study of homotheties, translations, rotations and reflections, we proceed now to the study of plane similarities, either direct or inverse. Their group theoretical properties are described, and their action on classical geometrical objects is…
Novel algorithm for complex bit reversal: employing vector permutation and branch reduction methods
Institute of Scientific and Technical Information of China (English)
Feng YU; Ze-ke WANG; Rui-feng GE
2009-01-01
We present novel vector permutation and branch reduction methods to minimize the number of execution cycles for bit reversal algorithms. The new methods are applied to single instruction multiple data (SIMD) parallel implementation of complex data floating-point fast Fourier transform (FFT). The number of operational clock cycles can be reduced by an average factor of 3.5 by using our vector permutation methods and by 1.1 by using our branch reduction methods, compared with conventional implementations. Experiments on MPC7448 (a well-known SIMD reduced instruction set computing processor) demonstrate that our optimal bit-reversal algorithm consistently takes fewer than two cycles per element in complex array operations.
Li, Boyu; Ayanoglu, Ender
2010-01-01
Multiple beamforming is realized by singular value decomposition of the channel matrix which is assumed to be perfectly known to the transmitter as well as the receiver. Bit-Interleaved Coded Multiple Beamforming (BICMB) is known to have a diversity order bound related with the product of the code rate and the number of parallel subchannels, losing the full diversity order in some cases. Bit-Interleaved Coded Multiple Beamforming with Constellation Precoding (BICMB-CP), on the other hand, can achieve the full diversity order. However, the decoding complexity of BICMB-CP is much higher than BICMB. In this paper, to reduce the complexity of Maximum Likelihood (ML) decoding for BICMB-CP, Sphere Decoding (SD) is used. Four novelties for SD are presented. Firstly, decoder bit metrics for the combination of BICMB-CP and SD are calculated. Secondly, zero-forcing decision feedback equalization technique is applied for the initial radius calculation of SD, which eliminates empty spheres and therefore prevents complexi...
Institute of Scientific and Technical Information of China (English)
Hao CHEN; Liqing XU
2011-01-01
The authors present an algorithm which is a modification of the Nguyen-Stehle greedy reduction algorithm due to Nguyen and Stehle in 2009.This algorithm can be used to compute the Minkowski reduced lattice bases for arbitrary rank lattices with quadratic bit complexity on the size of the input vectors.The total bit complexity of the algorithm is O(n2·(4n!)n·(n!/2n)n/2·(4/3)n(n-1)/2·log2A),wherenistherankofthe lattice and A is maximal norm of the input base vectors.This is an O(log2 A) algorithm which can be used to compute Minkowski reduced bases for the fixed rank lattices.A time complexity n! · 3n(log A)O(1) algorithm which can be used to compute the successive minima with the help of the dual Hermite-Korkin-Zolotarev base was given by Blomer in 2000 and improved to the time complexity n! · (log A)O(1) by Micciancio in 2008.The algorithm in this paper is more suitable for computing the Minkowski reduced bases of low rank lattices with very large base vector sizes.
Classification of flat slant surfaces in complex Euclidean plane
Chen, Bang-Yen
2002-01-01
It is well-known that the classification of flat surfaces in Euclidean 3space is one of the most basic results in differential geometry. For surfaces in the complex Euclidean plane $C^{2}$ endowed with almost complex structure $J$ , flat surfaces are the simplest ones from intrinsic point of views. On the other hand, from $J$ -action point of views, the most natural surfaces in $C^{2}$ are slant surfaces, i.e., surfaces with constant Wintinger angle. In this paper the author completely classi...
Critical $O(N)$ models in the complex field plane
Litim, Daniel F
2016-01-01
Local and global scaling solutions for $O(N)$ symmetric scalar field theories are studied in the complexified field plane with the help of the renormalisation group. Using expansions of the effective action about small, large, and purely imaginary fields, we obtain and solve exact recursion relations for all couplings and determine the $3d$ Wilson-Fisher fixed point analytically. For all $O(N)$ universality classes, we further establish that Wilson-Fisher fixed point solutions display singularities in the complex field plane, which dictate the radius of convergence for real-field expansions of the effective action. At infinite $N$, we find closed expressions for the convergence-limiting singularities and prove that local expansions of the effective action are powerful enough to uniquely determine the global Wilson-Fisher fixed point for any value of the fields. Implications of our findings for interacting fixed points in more complicated theories are indicated.
Classification of Flat Lagrangian Surfaces in Complex Lorentzian Plane
Institute of Scientific and Technical Information of China (English)
Bang-Yen CHEN; Johan FASTENAKELS
2007-01-01
One of the most fundamental problems in the study of Lagrangian submanifolds fromRiemannian geometric point of view is to classify Lagrangian immersions of real space forms intocomplex space forms. The main purpose of this paper is thus to classify flat Lagrangian surfaces inthe Lorentzian complex plane C12. Our main result states that there are thirty-eight families of flatLagrangian surfaces in C12. Conversely, every flat Lagrangian surface in C12 is locally congruent to oneof the thirty-eight families.
Isoperimetric inequality fortorsional rigidity in the complex plane
Directory of Open Access Journals (Sweden)
Salahudinov RG
2001-01-01
Full Text Available Suppose SZ is a simply connected domain in the complex plane. In (F.G. Avhadiev, Matem. Sborn., 189(12 (1998, 3–12 (Russian, Avhadiev introduced new geometrical functionals, which give two-sided estimates for the torsional rigidity of . In this paper we find sharp lower bounds for the ratio of the torsional rigidity to the new functionals. In particular, we prove that where is the torsional rigidity of , and is the conformal radius of at a point .
Painlevé differential equations in the complex plane
Gromak, Valerii I; Shimomura, Shun
2002-01-01
This book is the first comprehensive treatment of Painlevé differential equations in the complex plane. Starting with a rigorous presentation for the meromorphic nature of their solutions, the Nevanlinna theory will be applied to offer a detailed exposition of growth aspects and value distribution of Painlevé transcendents. The subsequent main part of the book is devoted to topics of classical background such as representations and expansions of solutions, solutions of special type like rational and special transcendental solutions, Bäcklund transformations and higher order analogues, treated separately for each of these six equations. The final chapter offers a short overview of applications of Painlevé equations, including an introduction to their discrete counterparts. Due to the present important role of Painlevé equations in physical applications, this monograph should be of interest to researchers in both mathematics and physics and to graduate students interested in mathematical physics and the th...
Generation of Triangular Meshes for Complex Domains on the Plane
Directory of Open Access Journals (Sweden)
Barbara Glut
2001-01-01
Full Text Available Many physical phenomena can be modeled by partial differential equations. The development of numerical methods based on the spatial subdivision of a domain into finite elements immediately extended interests to the tasks of generating a mesh. With the availability of versatile field solvers and powerful computers, the simulations of ever incrcasing geometrical and physical complexity are attempted. At some point the main bottleneck becomes the mesh generation itself. The paper presents a detailed description of the triangular mesh generation scheme on the plane based upon the Delaunay triangulation. A mesh generator should be fully automatic and simplify input data as much as possible. It should offer rapid gradation from small to large sizes of elements. The generated mesh must be always valid and of good quality. All these requirements were taken into account during the selection and elaboration of utilized algorithms. Successive chapters describe procedures connected with the specification of a modeled domain, generation and triangulation of boundary vertices, introducing inner nodes, improving the quality of the created mesh, and renumbering of vertices.
Implementing digital holograms to create and measure complex-plane optical fields
CSIR Research Space (South Africa)
Dudley, Angela L
2016-02-01
Full Text Available The coherent superposition of a Gaussian beam with an optical vortex can be mathematically described to occupy the complex plane. The authors provide a simple analogy between the mathematics, in the form of the complex plane, and the visual...
The Complexity of Searching Lines in the Plane: Preliminary Version.
1975-01-01
supported by ONR Grant N00014—75—C--0752. D*?*3~?*1O~~ STATEMENT A fet puNk :•lease; — bI.~lbe~ms UaMmit.d - — - ~~~~~~ 4...Let A be a set of lines in the plane. Then cOt) rCA) and c(A) log2iAJ . Proof: Recall tha t r(A) is the size of the largest region formed by A...Pr oof: - (1) Any search trees for A and B respectively can be combined to form one for AuB of size at most c(&) + eCU). (This
Myint, L. M. M.; Warisarn, C.
2017-05-01
Two-dimensional (2-D) interference is one of the prominent challenges in ultra-high density recording system such as bit patterned media recording (BPMR). The multi-track joint 2-D detection technique with the help of the array-head reading can tackle this problem effectively by jointly processing the multiple readback signals from the adjacent tracks. Moreover, it can robustly alleviate the impairments due to track mis-registration (TMR) and media noise. However, the computational complexity of such detectors is normally too high and hard to implement in a reality, even for a few multiple tracks. Therefore, in this paper, we mainly focus on reducing the complexity of multi-track joint 2-D Viterbi detector without paying a large penalty in terms of the performance. We propose a simplified multi-track joint 2-D Viterbi detector with a manageable complexity level for the BPMR's multi-track multi-head (MTMH) system. In the proposed method, the complexity of detector's trellis is reduced with the help of the joint-track equalization method which employs 1-D equalizers and 2-D generalized partial response (GPR) target. Moreover, we also examine the performance of a full-fledged multi-track joint 2-D detector and the conventional 2-D detection. The results show that the simplified detector can perform close to the full-fledge detector, especially when the system faces high media noise, with the significant low complexity.
Andrievskii, Vladimir
2006-01-01
This is a survey of some recent results concerning polynomial inequalities and polynomial approximation of functions in the complex plane. The results are achieved by the application of methods and techniques of modern geometric function theory and potential theory.
Two-Bit Bit Flipping Decoding of LDPC Codes
Nguyen, Dung Viet; Marcellin, Michael W
2011-01-01
In this paper, we propose a new class of bit flipping algorithms for low-density parity-check (LDPC) codes over the binary symmetric channel (BSC). Compared to the regular (parallel or serial) bit flipping algorithms, the proposed algorithms employ one additional bit at a variable node to represent its "strength." The introduction of this additional bit increases the guaranteed error correction capability by a factor of at least 2. An additional bit can also be employed at a check node to capture information which is beneficial to decoding. A framework for failure analysis of the proposed algorithms is described. These algorithms outperform the Gallager A/B algorithm and the min-sum algorithm at much lower complexity. Concatenation of two-bit bit flipping algorithms show a potential to approach the performance of belief propagation (BP) decoding in the error floor region, also at lower complexity.
On $q$-normal operators and quantum complex plane
Cimpri\\vc, Jaka; Schmüdgen, Konrad
2011-01-01
For $q>0$ let $\\cA$ denote the unital $\\ast$-algebra with generator $x$ and defining relation $xx^\\ast=qxx^\\ast$. Based on this algebra we study $q$-normal operators, the complex $q$-moment problem, positive elements and sums of squares.
Generation of Triangular Meshes for Complex Domains on the Plane
Barbara Glut; Tomasz Jurczyk
2001-01-01
Many physical phenomena can be modeled by partial differential equations. The development of numerical methods based on the spatial subdivision of a domain into finite elements immediately extended interests to the tasks of generating a mesh. With the availability of versatile field solvers and powerful computers, the simulations of ever incrcasing geometrical and physical complexity are attempted. At some point the main bottleneck becomes the mesh generation itself. The paper presents a deta...
Dynamics of Crowd Behaviors: From Complex Plane to Quantum Random Fields
Ivancevic, Vladimir G.; Reid, Darryn J.
2015-11-01
The following sections are included: * Complex Plane Dynamics of Crowds and Groups * Introduction * Complex-Valued Dynamics of Crowd and Group Behaviors * Kähler Geometry of Crowd and Group Dynamics * Computer Simulations of Crowds and Croups Dynamics * Braids of Agents' Behaviors in the Complex Plane * Hilbert-Space Control of Crowds and Groups Dynamics * Quantum Random Fields: A Unique Framework for Simulation, Optimization, Control and Learning * Introduction * Adaptive Quantum Oscillator * Optimization and Learning on Banach and Hilbert Spaces * Appendix * Complex-Valued Image Processing * Linear Integral Equations * Riemann-Liouville Fractional Calculus * Rigorous Geometric Quantization * Supervised Machine-Learning Methods * First-Order Logic and Quantum Random Fields
Linear Time Logics around PSL: Complexity, Expressiveness, and a little bit of Succinctness
DEFF Research Database (Denmark)
Lange, Martin
2007-01-01
restricted to certain operators only: basically, all operators alone suffice for expressive completeness w.r.t.\\ omega-regular expressions, just the closure operator is too weak. We also obtain complexity results. Again, almost all operators alone suffice for EXPSPACE-completeness, just the closure operator...
Multielectron High Harmonic Generation: simple man on a complex plane
Smirnova, Olga
2013-01-01
From the famous classical "simple man" model to the recent multichannel model for polyatomic molecules, this tutorial will guide you through the several landmarks in our understanding of high harmonic generation and high harmonic spectroscopy. Our goal was to provide recipes and insights for modelling the harmonic response in various regimes, from the single active electron regime typical for noble gas atoms to the laser-driven attosecond hole dynamics in polyatomics. We have tried to pay particular attention to both simple recipes and their limitations, including the connection of real-valued classical and complex-valued quantum times and velocities. In addition to physical pictures, general approaches and their practical realizations, we have also tried to discuss some of the sticky technical issues, such as the possibility to factorize high harmonic response into the three steps of ionization, propagation and recombination and practical ways to treat strong field ionization, search for the saddle points of...
Evaluation of Bit Preservation Strategies
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad; Kulovits, Hannes
2010-01-01
This article describes a methodology which supports evaluation of bit preservation strategies for different digital materials. This includes evaluation of alternative bit preservation solution. The methodology presented uses the preservation planning tool Plato for evaluations, and a BR......-ReMS prototype to calculate measures for how well bit preservation requirements are met. Planning storage of data as part of preservation planning involves classification of data with regard to requirements on confidentiality, bit safety, available and costs. Choice of storage with such parameters is quite...... complex since e.g. more copies of data means better bit safety, but higher cost and bigger risk of breaking confidentiality. Based on a case of a bit repository offering varied bit preservation solutions, the article will present results of using the methodology to make plans and choices of alternatives...
Hunter, Richard
2010-01-01
It is known that all weakly conformal Hamiltonian stationary Lagrangian immersions of tori in the complex projective plane may be constructed by methods from integrable systems theory. This article describes the precise details of a construction which leads to a form of classification. The immersion is encoded as spectral data in a similar manner to the case of minimal Lagrangian tori in the complex projective plane, but the details require a careful treatment of both the "dressing construction" and the spectral data to deal with a loop of flat connexions which is quadratic in the loop parameter.
Esquivel, Rodolfo O; Angulo, Juan Carlos; Antolín, Juan; Dehesa, Jesús S; López-Rosa, Sheila; Flores-Gallegos, Nelson
2010-07-14
The Fisher-Shannon and LMC shape complexities and the Shannon-disequilibrium, Fisher-Shannon and Fisher-disequilibrium information planes, which consist of two localization-delocalization factors, are computed in both position and momentum spaces for the one-particle densities of 90 selected molecules of various chemical types, at the CISD/6-311++G(3df,2p) level of theory. We found that while the two measures of complexity show general trends only, the localization-delocalization planes clearly exhibit chemically significant patterns. Several molecular properties (energy, ionization potential, total dipole moment, hardness, electrophilicity) are analyzed and used to interpret and understand the chemical nature of the composite information-theoretic measures above mentioned. Our results show that these measures detect not only randomness or localization but also pattern and organization.
Directory of Open Access Journals (Sweden)
Theocharis Theofanidis
2016-01-01
Full Text Available Real hypersurfaces satisfying the condition ϕl=lϕ(l=R(·,ξξ have been studied by many authors under at least one more condition, since the class of these hypersurfaces is quite tough to be classified. The aim of the present paper is the classification of real hypersurfaces in complex projective plane CP2 satisfying a generalization of ϕl=lϕ under an additional restriction on a specific function.
Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem
Institute of Scientific and Technical Information of China (English)
2008-01-01
The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.
Manned Versus Unmanned Risk and Complexity Considerations for Future Midsized X-Planes
Lechniak, Jason A.; Melton, John E.
2017-01-01
The objective of this work was to identify and estimate complexity and risks associated with the development and testing of new low-cost medium-scale X-plane aircraft primarily focused on air transport operations. Piloting modes that were evaluated for this task were manned, remotely piloted, and unmanned flight research programs. This analysis was conducted early in the data collection period for X-plane concept vehicles before preliminary designs were complete. Over 50 different aircraft and system topics were used to evaluate the three piloting control modes. Expert group evaluations from a diverse set of pilots, engineers, and other experts at Aeronautics Research Mission Directorate centers within the National Aeronautics and Space Administration provided qualitative reasoning on the many issues surrounding the decisions regarding piloting modes. The group evaluations were numerically rated to evaluate each topic quantitatively and were used to provide independent criteria for vehicle complexity and risk. An Edwards Air Force Base instruction document was identified that emerged as a source of the effects found in our qualitative and quantitative data. The study showed that a manned aircraft was the best choice to align with test activities for transport aircraft flight research from a low-complexity and low-risk perspective. The study concluded that a manned aircraft option would minimize the risk and complexity to improve flight-test efficiency and bound the cost of the flight-test portion of the program. Several key findings and discriminators between the three modes are discussed in detail.
Geometric reasoning about damped and forced harmonic motion in the complex plane
Close, Hunter G.
2015-09-01
Complex-valued functions are commonly used to solve differential equations for one-dimensional motion of a harmonic oscillator with linear damping, a sinusoidal driving force, or both. However, the usual approach treats complex functions as an algebraic shortcut, neglecting geometrical representations of those functions and discarding imaginary parts. This article emphasizes the benefit of using diagrams in the complex plane for such systems, in order to build intuition about harmonic motion and promote spatial reasoning and the use of varied representations. Examples include the analysis of exact time sequences of various kinematic events in damped harmonic motion, sense-making about the phase difference between a driving force and the resulting motion, and understanding the discrepancy between the resonant frequency and the natural undamped frequency for forced, damped harmonic motion. The approach is suitable for supporting instruction in undergraduate upper-division classical mechanics.
De Branges-Rovnyak realizations of operator-valued Schur functions on the complex right half-plane
Ball, Joseph A.; Kurula, Mikael; Staffans, Olof J.; Zwart, Hans
2015-01-01
We give a controllable energy-preserving and an observable co-energy-preserving de Branges-Rovnyak functional model realization of an arbitrary given operator Schur function defined on the complex right-half plane. We work the theory out fully in the right-half plane, without using results for the d
The complex equivalent source method for sound propagation over an impedance plane.
Ochmann, Martin
2004-12-01
The sound field caused by a monopole source above an impedance plane can be calculated by using a superposition of equivalent point sources located along a line in the mirror space below the plane. Originally, such an approach for representing the half-space Green's function was described by Sommerfeld at the beginning of the last century, in order to treat half-space problems of heat conduction. However, the representation converges only for masslike impedances and cannot be used for the more important case of reflecting planes with springlike surface impedances. The singular part of the line integral can be transformed into a Hankel function, which shows that surface waves are contained in the whole solution. Unfortunately, this representation suffers from the lack of validity at certain receiver points and from restrictions on wave number and impedance range to ensure the necessary convergence. The main idea of the present method is to use also a superposition of equivalent point sources, but to allow that these sources can be located at complex source points. The corresponding form of the half-space Green's function is suitable for both masslike and springlike surface impedances, and can be used as a cornerstone for a boundary element method.
Nuclear three-body problem in the complex energy plane: Complex-Scaling-Slater method
Kruppa, A T; Nazarewicz, W; Michel, N
2013-01-01
The physics of open quantum systems is an interdisciplinary area of research. The nuclear "openness" manifests itself through the presence of the many-body continuum representing various decay, scattering, and reaction channels. As the radioactive nuclear beam experimentation extends the known nuclear landscape towards the particle drip lines, the coupling to the continuum space becomes exceedingly more important. Of particular interest are weakly bound and unbound nuclear states appearing around particle thresholds. Theories of such nuclei must take into account their open quantum nature. To describe open quantum systems, we introduce a Complex Scaling (CS) approach in the Slater basis. We benchmark it with the complex-energy Gamow Shell Model (GSM) by studying energies and wave functions of the bound and unbound states of the two-neutron halo nucleus 6He viewed as an $\\alpha$+ n + n cluster system. In the CS approach, we use the Slater basis, which exhibits the correct asymptotic behavior at large distances...
Modeling of Ship Collision Risk Index Based on Complex Plane and Its Realization
Directory of Open Access Journals (Sweden)
Xiaoqin Xu
2016-07-01
Full Text Available Ship collision risk index is the basic and important concept in the domain of ship collision avoidance. In this paper, the advantages and deficiencies of the various calculation methods of ship collision risk index are pointed out. Then the ship collision risk model based on complex plane, which can well make up for the deficiencies of the widely-used evaluation model proposed by Kearon.J and Liu ruru is proposed. On this basis, the calculation method of collision risk index under the encountering situation of multi-ships is constructed, then the three-dimensional image and spatial curve of the risk index are figured out. Finally, single chip microcomputer is used to realize the model. And attaching this single chip microcomputer to ARPA is helpful to the decision-making of the marine navigators.
Discriminating image textures with the multiscale two-dimensional complexity-entropy causality plane
Zunino, Luciano
2016-01-01
The aim of this paper is to further explore the usefulness of the two-dimensional complexity-entropy causality plane as a texture image descriptor. A multiscale generalization is introduced in order to distinguish between different roughness features of images at small and large spatial scales. Numerically generated two-dimensional structures are initially considered for illustrating basic concepts in a controlled framework. Then, more realistic situations are studied. Obtained results allow us to confirm that intrinsic spatial correlations of images are successfully unveiled by implementing this multiscale symbolic information-theory approach. Consequently, we conclude that the proposed representation space is a versatile and practical tool for identifying, characterizing and discriminating image textures.
A dynamic finite element analysis of human foot complex in the sagittal plane during level walking.
Qian, Zhihui; Ren, Lei; Ding, Yun; Hutchinson, John R; Ren, Luquan
2013-01-01
The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%-33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning.
A dynamic finite element analysis of human foot complex in the sagittal plane during level walking.
Directory of Open Access Journals (Sweden)
Zhihui Qian
Full Text Available The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%-33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning.
Anharmonic oscillators in the complex plane, $\\mathcal{PT}$-symmetry, and real eigenvalues
Shin, Kwang C
2010-01-01
For integers $m\\geq 3$ and $1\\leq\\ell\\leq m-1$, we study the eigenvalue problems $-u^{\\prime\\prime}(z)+[(-1)^{\\ell}(iz)^m-P(iz)]u(z)=\\lambda u(z)$ with the boundary conditions that $u(z)$ decays to zero as $z$ tends to infinity along the rays $\\arg z=-\\frac{\\pi}{2}\\pm \\frac{(\\ell+1)\\pi}{m+2}$ in the complex plane, where $P$ is a polynomial of degree at most $m-1$. We provide asymptotic expansions of the eigenvalues $\\lambda_{n}$. Then we show that if the eigenvalue problem is $\\mathcal{PT}$-symmetric, then the eigenvalues are all real and positive with at most finitely many exceptions. Moreover, we show that when $\\gcd(m,\\ell)=1$, the eigenvalue problem has infinitely many real eigenvalues if and only if its translation or itself is $\\mathcal{PT}$-symmetric. Also, we will prove some other interesting direct and inverse spectral results.
Earth-Facing Antenna Characterization in a Complex Ground Plane/Multipath Rich Environment
Welch, Bryan W.; Piasecki, Marie T.
2015-01-01
The Space Communications and Navigation (SCAN) Testbed was a Software Defined Radio (SDR)-based payload launched to the International Space Station (ISS) in July of 2012. The purpose of the SCAN Testbed payload was to investigate the applicability of SDRs to NASA space missions in an operational space environment, which means that a proper model for system performance in said operational space environment is a necessary condition. The SCAN Testbed has line-of-sight connections to various ground stations with its S-Band Earth-facing Near-Earth Network Low Gain Antenna (NEN-LGA). Any previous efforts to characterize the NEN-LGA proved difficult, therefore, the NASA Glenn Research Center built its own S-Band ground station, which became operational in 2015, and has been successfully used to characterize the NEN-LGAs in-situ pattern measurements. This methodology allows for a more realistic characterization of the antenna performance, where the pattern oscillation induced by the complex ISS ground plane, as well as shadowing effects due to ISS structural blockage are included into the final performance model. This paper describes the challenges of characterizing an antenna pattern in this environment. It will also discuss the data processing, present the final antenna pattern measurements and derived model, as well as discuss various lessons learned.
Earth-Facing Antenna Characterization in Complex Ground Plane/Multipath Rich Environment
Welch, Bryan W.; Piasecki, Marie T.
2015-01-01
The Space Communications and Navigation (SCAN) Testbed was a Software Defined Radio (SDR)-based payload launched to the International Space Station (ISS) in July of 2012. The purpose of the SCAN Testbed payload was to investigate the applicability of SDRs to NASA space missions in an operational environment, which means that a proper model for system performance in said operational space environment is a necessary condition. The SCAN Testbed has line-of-sight connections to various ground stations with its S-Band Earth-facing Near-Earth-Network Low Gain Antenna (NEN-LGA). Any previous efforts to characterize the NEN-LGA proved difficult, therefore, the NASA Glenn Research Center built its own S-Band ground station, which became operational in 2015, and has been used successfully to characterize the NEN-LGA's in-situ pattern measurements. This methodology allows for a more realistic characterization of the antenna performance, where the pattern oscillation induced by the complex ISS ground plane, as well as shadowing effects due to ISS structural blockage are included into the final performance model. This paper describes the challenges of characterizing an antenna pattern in this environment. It will also discuss the data processing, present the final antenna pattern measurements and derived model, as well as discuss various lessons learned
Dekker, B.G.; Sluyters-Rehbach, M.; Sluyters, J.H.
1969-01-01
The applicability of the complex plane method for the evaluation of the impedance parameters in the case of two simultaneously proceeding electrode reactions is discussed. It is shown that the possibility of the evaluation depends strongly on the values of the irreversibility quotients of both react
Degree of a isolated real point or a singular complex point on a plane curve defined over Q
DEFF Research Database (Denmark)
Hansen, Johan Peder
2010-01-01
Let $X$ be a curve in the affine plane defined by a reduced polynomial of degree $d$ with rational coefficients. Assume that $P$ is an isolated real point or a singular complex point on the curve $X$. The coordinates of $P$ are algebraic numbers over the rationals of degree at most $d^2$. The res...
Conversion of an 8-bit to a 16-bit Soft-core RISC Processor
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Ahmad Jamal Salim
2013-03-01
Full Text Available The demand for 8-bit processors nowadays is still going strong despite efforts by manufacturers in producing higher end microcontroller solutions to the mass market. Low-end processor offers a simple, low-cost and fast solution especially on I/O applications development in embedded system. However, due to architectural constraint, complex calculation could not be performed efficiently on 8-bit processor. This paper presents the conversion method from an 8-bit to a 16-bit Reduced Instruction Set Computer (RISC processor in a soft-core reconfigurable platform in order to extend its capability in handling larger data sets thus enabling intensive calculations process. While the conversion expands the data bus width to 16-bit, it also maintained the simple architecture design of an 8-bit processor.The expansion also provides more room for improvement to the processor’s performance. The modified architecture is successfully simulated in CPUSim together with its new instruction set architecture (ISA. Xilinx Virtex-6 platform is utilized to execute and verified the architecture. Results show that the modified 16-bit RISC architecture only required 17% more register slice on Field Programmable Gate Array (FPGA implementation which is a slight increase compared to the original 8-bit RISC architecture. A test program containing instruction sets that handle 16-bit data are also simulated and verified. As the 16-bit architecture is described as a soft-core, further modifications could be performed in order to customize the architecture to suit any specific applications.
Ovsiyuk, E M; Red'kov, V M
2010-01-01
The aim of the article to clarify the status of Shapiro plane wave solutions of the Schr\\"odinger's equation in the frames of the well-known general method of separation of variables. To solve this task, we use the well-known cylindrical coordinates in Riemann and Lobachevsky spaces, naturally related with Euler angle-parameters. Conclusion may be drawn: the general method of separation of variables embraces the all plane wave solutions; the plane waves in Lobachevsky and Riemann space consist of a small part of the whole set of basis wave functions of Schr\\"odinger equation. In space of constant positive curvature $S_{3}$, a complex analog of horospherical coordinates of Lobachevsky space $H_{3}$ is introduced. To parameterize real space $S_{3}$, two complex coordinates $(r,z)$ must obey additional restriction in the form of the equation $r^{2} = e^{z-z^{*}} - e^{2z} $. The metrical tensor of space $S_{3}$ is expressed in terms of $(r,z)$ with additional constraint, or through pairs of conjugate variables $(...
Morrell, Roger J.; Larson, David A.; Ruzzi, Peter L.
1994-01-01
A double acting bit holder that permits bits held in it to be resharpened during cutting action to increase energy efficiency by reducing the amount of small chips produced. The holder consist of: a stationary base portion capable of being fixed to a cutter head of an excavation machine and having an integral extension therefrom with a bore hole therethrough to accommodate a pin shaft; a movable portion coextensive with the base having a pin shaft integrally extending therefrom that is insertable in the bore hole of the base member to permit the moveable portion to rotate about the axis of the pin shaft; a recess in the movable portion of the holder to accommodate a shank of a bit; and a biased spring disposed in adjoining openings in the base and moveable portions of the holder to permit the moveable portion to pivot around the pin shaft during cutting action of a bit fixed in a turret to allow front, mid and back positions of the bit during cutting to lessen creation of small chip amounts and resharpen the bit during excavation use.
Adaptive bit truncation and compensation method for EZW image coding
Dai, Sheng-Kui; Zhu, Guangxi; Wang, Yao
2003-09-01
The embedded zero-tree wavelet algorithm (EZW) is widely adopted to compress wavelet coefficients of images with the property that the bits stream can be truncated and produced anywhere. The lower bit plane of the wavelet coefficents is verified to be less important than the higher bit plane. Therefore it can be truncated and not encoded. Based on experiments, a generalized function, which can provide a glancing guide for EZW encoder to intelligently decide the number of low bit plane to be truncated, is deduced in this paper. In the EZW decoder, a simple method is presented to compensate for the truncated wavelet coefficients, and finally it can surprisingly enhance the quality of reconstructed image and spend scarcely any additional cost at the same time.
Alpha coding of arbitrarily shaped objects for low-bit-rate MPEG-4
Hadar, Ofer; Folkman, Hagai
2001-11-01
This paper presents a new scheme for compact shape-coding which can reduce the needed bandwidth for low bit rate MPEG- 4 applications. Our scheme is based on a coarse representation of the alpha plane with a block size resolution of 8x8 pixels. This arrangement saves bandwidth and reduces the algorithm complexity (number of computations), as compared to the Content-based Arithmetic Encoding (CAE) algorithm. In our algorithm, we encode the alpha plane of a macroblock with only 4 bits, while we can further reduce the number of encoding bits by using the Huffman code. The encoding blocks are only contour macroblocks, transparent macroblocks are considered as background macroblocks, while opaque macroblocks are considered as object macroblocks. We show that the amount of bandwidth saving with representing the alpha-plane can reach a factor of 9.5. Such a scheme is appropriate for mobile applications where there is a lack of both bandwidth and processing power. We also speculate that our scheme will be compatible to the MPEG-4 standard.
Bit Loading Algorithms for Cooperative OFDM Systems
Directory of Open Access Journals (Sweden)
Bo Gui
2007-12-01
Full Text Available We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.
Bit Loading Algorithms for Cooperative OFDM Systems
Directory of Open Access Journals (Sweden)
Gui Bo
2008-01-01
Full Text Available Abstract We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.
Sainath, Kamalesh; Donderici, Burkay
2013-01-01
We propose the complex-plane generalization of a powerful algebraic sequence acceleration algorithm, the Method of Weighted Averages (MWA), to guarantee \\emph{exponential-cum-algebraic} convergence of Fourier and Fourier-Hankel (F-H) integral transforms. This "complex-plane" MWA, effected via a linear-path detour in the complex plane, results in rapid, absolute convergence of field/potential solutions in multi-layered environments \\emph{regardless} of the source-observer geometry and anisotropy/loss of the media present. In this work, we first introduce a new integration path used to evaluate the field contribution arising from the radiation spectra. Subsequently, we (1) exhibit the foundational relations behind the complex-plane extension to a general Levin-type sequence convergence accelerator, (2) specialize this analysis to one member of the Levin transform family (the MWA), (3) address and circumvent restrictions, arising for two-dimensional integrals associated with wave dynamics problems, through minim...
The decay of plane wave pulses with complex structure in a nonlinear dissipative medium
Gurbatov, S N; Pasmanik, G V; Gurbatov, Sergei N.; Enflo, Bengt O.; Pasmanik, Galina V.
2000-01-01
Nonlinear plane acoustic waves propagating through a fluid are studied using Burgers' equation with finite viscosity. The evolution of a simple N-pulse with regular and random initial amplitude and of pulses with monochromatic and noise carrier is considered. In the latter case the initial pulses are characterized by two length scales. The length scale of the modulation function is much greater than the period or the length scale of the carrier. With increasing time the initial pulses are deformed and shocks appear. The finite viscosity leads to a finite shock width, which does not depend on the fine structure of the initial pulse and is fully determined by the shock position in the zero viscosity limit. The other effect of nonzero viscosity is the shift of the shock position from the position at zero viscosity. This shift, as well as the linear time, at which the nonlinear stage of evolution changes to the linear stage, depends on the fine structure of the initial pulse. It is also shown that the nonlinearit...
An analytical solution in the complex plane for the luminosity distance in flat cosmology
Zaninetti, L
2016-01-01
We present an analytical solution for the luminosity distance in spatially flat cosmology with pressureless matter and the cosmological constant. The complex analytical solution is made of a real part and a negligible imaginary part. The real part of the luminosity distance allows finding the two parameters $H_0$ and $\\om$. A simple expression for the distance modulus for SNs of type Ia is reported in the framework of the minimax approximation.
Sainath, Kamalesh; Teixeira, Fernando L
2014-05-01
We discuss the application of complex-plane Gauss-Laguerre quadrature (CGLQ) to efficiently evaluate two-dimensional Fourier integrals arising as the solution to electromagnetic fields radiated by elementary dipole antennas embedded within planar-layered media exhibiting arbitrary material parameters. More specifically, we apply CGLQ to the long-standing problem of rapidly and efficiently evaluating the semi-infinite length "tails" of the Fourier integral path while simultaneously and robustly guaranteeing absolute, exponential convergence of the field solution despite diversity in the doubly anisotropic layer parameters, source type (i.e., electric or equivalent magnetic dipole), source orientation, observed field type (magnetic or electric), (nonzero) frequency, and (nonzero) source-observer separation geometry. The proposed algorithm exhibits robustness despite unique challenges arising for the fast evaluation of such two-dimensional integrals. Herein we develop the mathematical treatment to rigorously evaluate the tail integrals using CGLQ, as well as discuss and address the specific issues posed to the CGLQ method when anisotropic, layered media are present. To empirically demonstrate the CGLQ algorithm's computational efficiency, versatility, and accuracy, we perform a convergence analysis along with two case studies related to modeling of electromagnetic resistivity tools employed in geophysical prospection of layered, anisotropic Earth media and validating the ability of isoimpedance substrates to enhance the radiation performance of planar antennas placed in close proximity to metallic ground planes.
Directory of Open Access Journals (Sweden)
Ayhan Tutar
2015-01-01
Full Text Available The Steiner area formula and the polar moment of inertia were expressed during one-parameter closed planar homothetic motions in complex plane. The Steiner point or Steiner normal concepts were described according to whether rotation number was different from zero or equal to zero, respectively. The moving pole point was given with its components and its relation between Steiner point or Steiner normal was specified. The sagittal motion of a winch was considered as an example. This motion was described by a double hinge consisting of the fixed control panel of winch and the moving arm of winch. The results obtained in the second section of this study were applied for this motion.
Sainath, Kamalesh
2014-01-01
We discuss the application of Complex-Plane Gauss-Laguerre Quadrature (CGLQ) to efficiently evaluate two-dimensional Fourier integrals arising as the solution to electromagnetic fields radiated by elementary dipole antennas embedded within planar-layered media with arbitrary material parameters. More specifically, we apply CGLQ to the long-standing problem of rapidly and efficiently evaluating the semi-infinite length "tails" of the Fourier integral path while simultaneously and robustly guaranteeing absolute, exponential convergence of the field solution despite diversity in the doubly anisotropic layer parameters, source type (i.e., electric or equivalent magnetic dipole), source orientation, observed field type (magnetic or electric), (non-zero) frequency, and (non-zero) source-observer separation geometry. The proposed algorithm exhibits robustness despite unique challenges arising for the fast evaluation of such two-dimensional integrals. Herein, we (1) develop the mathematical treatment to rigorously ev...
Directory of Open Access Journals (Sweden)
I. I. Kravchenko
2016-01-01
Full Text Available Experience in application of multi-operational machines CNC (MOM CNC shows that they are efficient only in case of significantly increasing productivity and dramatically reducing time-to-market cycle of new products. Most full technological MOM capabilities are revealed when processing the complex body parts. The more complex is a part design and the more is its number of machined surfaces, the more tools are necessary for its processing and positioning, the more is an efficiency of their application. At the same time, the case history of using these machines in industry shows that MOM CNC are, virtually, used mostly for technological processes of universal equipment, which is absolutely unacceptable. One way to improve the processing performance on MOM CNC is to reduce nonproductive machine time through reducing the mutual idle movements of the working machine. This problem is solved using dynamic programming methods, one of which is the solution of the traveling salesman problem (Bellman's method. With a known plan for treatment of all elementary surfaces of the body part, i.e. the known number of performed transitions, each transition is represented as a vertex of some graph, while technological links between the vertices are its edges. A mathematical model is developed on the Bellman principle, which is adapted to technological tasks to minimize the idle time of mutual idle movements of the working machine to perform all transitions in the optimal sequence. The initial data to fill matrix of time expenditures are time consumed by the hardware after executing the i-th transition, and necessary to complete the j-transition. The programmer fills in matrix cells according to known routing body part taking into account the time for part and table positioning, tool exchange, spindle and table approach to the working zone, and the time of table rotation, etc. The mathematical model was tested when machining the body part with 36 transitions on the
Institute of Scientific and Technical Information of China (English)
Yang Yukun; Han Tao
1995-01-01
@@ The geologic condition of Shengli Oilfield (SLOF)is complicated and the range of the rock drillability is wide. For more than 20 years,Shengli Drilling Technology Research Institute, in view of the formation conditions of SLOF,has done a lot of effort and obtained many achivements in design,manufacturing technology and field service. Up to now ,the institute has developed several ten kinds of diamond bits applicable for drilling and coring in formations from extremely soft to hard.
Efficient Algorithms for Optimal 4-Bit Reversible Logic System Synthesis
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Zhiqiang Li
2013-01-01
Full Text Available Owing to the exponential nature of the memory and run-time complexity, many methods can only synthesize 3-bit reversible circuits and cannot synthesize 4-bit reversible circuits well. We mainly absorb the ideas of our 3-bit synthesis algorithms based on hash table and present the efficient algorithms which can construct almost all optimal 4-bit reversible logic circuits with many types of gates and at mini-length cost based on constructing the shortest coding and the specific topological compression; thus, the lossless compression ratio of the space of n-bit circuits reaches near 2×n!. This paper presents the first work to create all 3120218828 optimal 4-bit reversible circuits with up to 8 gates for the CNT (Controlled-NOT gate, NOT gate, and Toffoli gate library, and it can quickly achieve 16 steps through specific cascading created circuits.
Bit-padding information guided channel hopping
Yang, Yuli
2011-02-01
In the context of multiple-input multiple-output (MIMO) communications, we propose a bit-padding information guided channel hopping (BP-IGCH) scheme which breaks the limitation that the number of transmit antennas has to be a power of two based on the IGCH concept. The proposed scheme prescribes different bit-lengths to be mapped onto the indices of the transmit antennas and then uses padding technique to avoid error propagation. Numerical results and comparisons, on both the capacity and the bit error rate performances, are provided and show the advantage of the proposed scheme. The BP-IGCH scheme not only offers lower complexity to realize the design flexibility, but also achieves better performance. © 2011 IEEE.
Positional information, in bits.
Dubuis, Julien O; Tkacik, Gasper; Wieschaus, Eric F; Gregor, Thomas; Bialek, William
2013-10-08
Cells in a developing embryo have no direct way of "measuring" their physical position. Through a variety of processes, however, the expression levels of multiple genes come to be correlated with position, and these expression levels thus form a code for "positional information." We show how to measure this information, in bits, using the gap genes in the Drosophila embryo as an example. Individual genes carry nearly two bits of information, twice as much as would be expected if the expression patterns consisted only of on/off domains separated by sharp boundaries. Taken together, four gap genes carry enough information to define a cell's location with an error bar of ~1 along the anterior/posterior axis of the embryo. This precision is nearly enough for each cell to have a unique identity, which is the maximum information the system can use, and is nearly constant along the length of the embryo. We argue that this constancy is a signature of optimality in the transmission of information from primary morphogen inputs to the output of the gap gene network.
Robust relativistic bit commitment
Chakraborty, Kaushik; Chailloux, André; Leverrier, Anthony
2016-12-01
Relativistic cryptography exploits the fact that no information can travel faster than the speed of light in order to obtain security guarantees that cannot be achieved from the laws of quantum mechanics alone. Recently, Lunghi et al. [Phys. Rev. Lett. 115, 030502 (2015), 10.1103/PhysRevLett.115.030502] presented a bit-commitment scheme where each party uses two agents that exchange classical information in a synchronized fashion, and that is both hiding and binding. A caveat is that the commitment time is intrinsically limited by the spatial configuration of the players, and increasing this time requires the agents to exchange messages during the whole duration of the protocol. While such a solution remains computationally attractive, its practicality is severely limited in realistic settings since all communication must remain perfectly synchronized at all times. In this work, we introduce a robust protocol for relativistic bit commitment that tolerates failures of the classical communication network. This is done by adding a third agent to both parties. Our scheme provides a quadratic improvement in terms of expected sustain time compared with the original protocol, while retaining the same level of security.
Sainath, Kamalesh; Teixeira, Fernando L.; Donderici, Burkay
2014-07-01
We propose the complex-plane generalization of a powerful algebraic sequence acceleration algorithm, the method of weighted averages (MWA), to guarantee exponential-cum-algebraic convergence of Fourier and Fourier-Hankel (F-H) integral transforms. This “complex-plane” MWA, effected via a linear-path detour in the complex plane, results in rapid, absolute convergence of field and potential solutions in multi-layered environments regardless of the source-observer geometry and anisotropy/loss of the media present. In this work, we first introduce a new integration path used to evaluate the field contribution arising from the radiation spectra. Subsequently, we (1) exhibit the foundational relations behind the complex-plane extension to a general Levin-type sequence convergence accelerator, (2) specialize this analysis to one member of the Levin transform family (the MWA), (3) address and circumvent restrictions, arising for two-dimensional integrals associated with wave dynamics problems, through minimal complex-plane detour restrictions and a novel partition of the integration domain, (4) develop and compare two formulations based on standard/real-axis MWA variants, and (5) present validation results and convergence characteristics for one of these two formulations.
Eliasson, H
2001-07-01
Recently, it has been shown that the higher-order A3 and A4 scenarios of the mode-coupling theory (MCT) are in many cases capable of providing a good description of the complicated dielectric spectra often encountered in polymeric systems. In this paper, more data from dielectric measurements on poly(ethylene terephthalate), poly(vinylidene fluoride), Nylon-66, poly(chlorotrifluoroethylene) (PCTFE), and the polymer gel system poly(acrylonitrile)-ethylene carbonate-propylene carbonate are evaluated within the A4 scenario of the MCT. For all these systems, very good agreement is found between the theoretical and experimental spectra. The data analysis is demonstrated to be facilitated considerably by plotting the data in the complex plane whereby the elliptic functions derived from the theory for the frequency-dependent dielectric function can be replaced by polynomials. For PCTFE, the scaling behavior predicted by the MCT could be verified and the temperature dependences of the extracted scaling parameters were found to be consistent with theory.
Institute of Scientific and Technical Information of China (English)
刘官厅; 范天佑
2003-01-01
The complex method of the plane elasticity in 2D quasicrystal with point group 10 mm tenfold rotational symmetry is established. First displacement potential function in the quasicrystal is represented by four analytic functions. Then by utilizing the properties of analytic function and through a great deal of derivation, the complex representations of stresses and displacements components of phonon fields and phason fields in the quasicrystal are given, which are the theoretical foundation for this method. From this theory, and by the help of conformal transformations in the theory of complex function, the problems of elliptic hole in the quasicrystal are solved. Its special cases are the solutions of well-known crack problem. Meanwhile, the results show that even if under the self-counterbalance force in the quasicrystal plane with elliptic hole, the stress components of phonon fields are also related to material constants of the quasicrystal when the phonon fields and phason fields are coupled, which is another distinctive difference from the properties of classical elastic theory. Besides, the present work is generalization and application of the complex method in the classical elastic theory established by Muskhelishvili to 2D quasicrystal. As in the classical elastic theory, if only conformal transformation from the quasicrystal plane to unit circle is found, any holey and crack problem in the quasicrystal plane could be solved.
Evaluation of Bit Preservation Strategies
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad; Kulovits, Hannes
2010-01-01
This article describes a methodology which supports evaluation of bit preservation strategies for different digital materials. This includes evaluation of alternative bit preservation solution. The methodology presented uses the preservation planning tool Plato for evaluations, and a BR...... for different digital material with different requirements for bit integrity and confidentiality. This case shows that the methodology, including the tools used, is useful for this purpose....
Design of 1.5 bit quantization correlator in satellite navigation software receiver
Institute of Scientific and Technical Information of China (English)
Hongwei Zhou; Tian Jin; Fangyao L
2016-01-01
Currently, 1 bit or 2 bit signal quantization is widely used in satelite navigation software receivers. The bit-wise paralel algorithm has been proposed for 1 bit and 2 bit signal quantization, which performs correlation with high efficiency. In order to improve the performance of the correlator, this paper proposes a new 1.5 bit quantization method. Theoreti-cal analyses are made from the aspects of complexity and quantization loss, and performance comparison between 1.5 bit quantization correlator and traditional correlators is dis-cussed. The results show that the 1.5 bit quantization algo-rithm can save about 30 percent complexity under similar quantization loss, reduce more than 0.5 dB signal noise ratio (SNR) loss under similar complexity. It shows great perform-ance improvement for correlators of satelite navigation soft-ware receivers.
Bit-Serial Adder Based on Quantum Dots
Fijany, Amir; Toomarian, Nikzad; Modarress, Katayoon; Spotnitz, Mathew
2003-01-01
A proposed integrated circuit based on quantum-dot cellular automata (QCA) would function as a bit-serial adder. This circuit would serve as a prototype building block for demonstrating the feasibility of quantum-dots computing and for the further development of increasingly complex and increasingly capable quantum-dots computing circuits. QCA-based bit-serial adders would be especially useful in that they would enable the development of highly parallel and systolic processors for implementing fast Fourier, cosine, Hartley, and wavelet transforms. The proposed circuit would complement the QCA-based circuits described in "Implementing Permutation Matrices by Use of Quantum Dots" (NPO-20801), NASA Tech Briefs, Vol. 25, No. 10 (October 2001), page 42 and "Compact Interconnection Networks Based on Quantum Dots" (NPO-20855), which appears elsewhere in this issue. Those articles described the limitations of very-large-scale-integrated (VLSI) circuitry and the major potential advantage afforded by QCA. To recapitulate: In a VLSI circuit, signal paths that are required not to interact with each other must not cross in the same plane. In contrast, for reasons too complex to describe in the limited space available for this article, suitably designed and operated QCA-based signal paths that are required not to interact with each other can nevertheless be allowed to cross each other in the same plane without adverse effect. In principle, this characteristic could be exploited to design compact, coplanar, simple (relative to VLSI) QCA-based networks to implement complex, advanced interconnection schemes. To enable a meaningful description of the proposed bit-serial adder, it is necessary to further recapitulate the description of a quantum-dot cellular automation from the first-mentioned prior article: A quantum-dot cellular automaton contains four quantum dots positioned at the corners of a square cell. The cell contains two extra mobile electrons that can tunnel (in the
... it or try to play with it. These spiders will not bite you unless they feel threatened — if you leave them alone, they will leave you alone. For Teens For ... Stung Me! Hey! A Scorpion Stung Me! Hey! A Black Widow Spider Bit Me! Hey! A Brown Recluse Spider Bit ...
Experimental unconditionally secure bit commitment
Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adan; Pan, Jian-Wei
2014-03-01
Quantum physics allows unconditionally secure communication between parties that trust each other. However, when they do not trust each other such as in the bit commitment, quantum physics is not enough to guarantee security. Only when relativistic causality constraints combined, the unconditional secure bit commitment becomes feasible. Here we experimentally implement a quantum bit commitment with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. Bits are successfully committed with less than 5 . 68 ×10-2 cheating probability. This provides an experimental proof of unconditional secure bit commitment and demonstrates the feasibility of relativistic quantum communication.
Bit Preservation: A Solved Problem?
Directory of Open Access Journals (Sweden)
David S. H. Rosenthal
2010-07-01
Full Text Available For years, discussions of digital preservation have routinely featured comments such as “bit preservation is a solved problem; the real issues are ...”. Indeed, current digital storage technologies are not just astoundingly cheap and capacious, they are astonishingly reliable. Unfortunately, these attributes drive a kind of “Parkinson’s Law” of storage, in which demands continually push beyond the capabilities of systems implementable at an affordable price. This paper is in four parts:Claims, reviewing a typical claim of storage system reliability, showing that it provides no useful information for bit preservation purposes.Theory, proposing “bit half-life” as an initial, if inadequate, measure of bit preservation performance, expressing bit preservation requirements in terms of it, and showing that the requirements being placed on bit preservation systems are so onerous that the experiments required to prove that a solution exists are not feasible.Practice, reviewing recent research into how well actual storage systems preserve bits, showing that they fail to meet the requirements by many orders of magnitude.Policy, suggesting ways of dealing with this unfortunate situation.
Towards constructing multi-bit binary adder based on Belousov-Zhabotinsky reaction.
Zhang, Guo-Mao; Wong, Ieong; Chou, Meng-Ta; Zhao, Xin
2012-04-28
It has been proposed that the spatial excitable media can perform a wide range of computational operations, from image processing, to path planning, to logical and arithmetic computations. The realizations in the field of chemical logical and arithmetic computations are mainly concerned with single simple logical functions in experiments. In this study, based on Belousov-Zhabotinsky reaction, we performed simulations toward the realization of a more complex operation, the binary adder. Combining with some of the existing functional structures that have been verified experimentally, we designed a planar geometrical binary adder chemical device. Through numerical simulations, we first demonstrated that the device can implement the function of a single-bit full binary adder. Then we show that the binary adder units can be further extended in plane, and coupled together to realize a two-bit, or even multi-bit binary adder. The realization of chemical adders can guide the constructions of other sophisticated arithmetic functions, ultimately leading to the implementation of chemical computer and other intelligent systems.
Towards constructing multi-bit binary adder based on Belousov-Zhabotinsky reaction
Zhang, Guo-Mao; Wong, Ieong; Chou, Meng-Ta; Zhao, Xin
2012-04-01
It has been proposed that the spatial excitable media can perform a wide range of computational operations, from image processing, to path planning, to logical and arithmetic computations. The realizations in the field of chemical logical and arithmetic computations are mainly concerned with single simple logical functions in experiments. In this study, based on Belousov-Zhabotinsky reaction, we performed simulations toward the realization of a more complex operation, the binary adder. Combining with some of the existing functional structures that have been verified experimentally, we designed a planar geometrical binary adder chemical device. Through numerical simulations, we first demonstrated that the device can implement the function of a single-bit full binary adder. Then we show that the binary adder units can be further extended in plane, and coupled together to realize a two-bit, or even multi-bit binary adder. The realization of chemical adders can guide the constructions of other sophisticated arithmetic functions, ultimately leading to the implementation of chemical computer and other intelligent systems.
Steganography forensics method for detecting least significant bit replacement attack
Wang, Xiaofeng; Wei, Chengcheng; Han, Xiao
2015-01-01
We present an image forensics method to detect least significant bit replacement steganography attack. The proposed method provides fine-grained forensics features by using the hierarchical structure that combines pixels correlation and bit-planes correlation. This is achieved via bit-plane decomposition and difference matrices between the least significant bit-plane and each one of the others. Generated forensics features provide the susceptibility (changeability) that will be drastically altered when the cover image is embedded with data to form a stego image. We developed a statistical model based on the forensics features and used least square support vector machine as a classifier to distinguish stego images from cover images. Experimental results show that the proposed method provides the following advantages. (1) The detection rate is noticeably higher than that of some existing methods. (2) It has the expected stability. (3) It is robust for content-preserving manipulations, such as JPEG compression, adding noise, filtering, etc. (4) The proposed method provides satisfactory generalization capability.
low bit rate video coding low bit rate video coding
African Journals Online (AJOL)
eobe
ariable length bit rate (VLBR) broadly encompasses video coding which broadly encompasses ... for motion estimation and compensation to reduce the prediction sation to reduce the ... a special interest among the video coding community ...
Institute of Scientific and Technical Information of China (English)
孔荫莹
2013-01-01
By using a Type-function of Sun, the growth of the Laplace-Stieltjes transform convergent in the whole complex plane are obtained, which cover and extend some results of Dirichlet series.%应用孙道椿一个无穷级的型函数,研究复平面解析的Laplace-Stieltjes变换的增长性,推广了Dirichlet级数的相关结论.
DRILL BITS FOR HORIZONTAL WELLS
Directory of Open Access Journals (Sweden)
Paolo Macini
1996-12-01
Full Text Available This paper underlines the importance of the correct drill bit application in horizontal wells. Afler the analysis of the peculiarities of horizontal wells and drainholes drilling techniques, advantages and disadvantages of the application of both roller cone and fixed cutters drill bits have been discussed. Also, a review of the potential specific featuries useful for a correct drill bit selection in horizontal small diameter holes has been highlighted. Drill bits for these special applications, whose importance is quickly increasing nowadays, should be characterised by a design capable to deliver a good penetration rate low WOB, and, at the same time, be able to withstand high RPM without premature cutting structure failure and undergauge. Formation properties will also determine the cutting structure type and the eventual specific features for additional gauge and shoulder protection.
... Hey! A Bee Stung Me! Rashes: The Itchy Truth Hey! A Mosquito Bit Me! Contact Us Print ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...
... Hey! A Chigger Bit Me! Rashes: The Itchy Truth Contact Us Print Resources Send to a Friend ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...
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8 Bit RISC Processor Using Verilog HDL
Directory of Open Access Journals (Sweden)
Ramandeep Kaur
2014-03-01
Full Text Available RISC is a design philosophy to reduce the complexity of instruction set that in turn reduces the amount of space, cycle time, cost and other parameters taken into account during the implementation of the design. The advent of FPGA has enabled the complex logical systems to be implemented on FPGA. The intent of this paper is to design and implement 8 bit RISC processor using FPGA Spartan 3E tool. This processor design depends upon design specification, analysis and simulation. It takes into consideration very simple instruction set. The momentous components include Control unit, ALU, shift registers and accumulator register.
String bit models for superstring
Energy Technology Data Exchange (ETDEWEB)
Bergman, O.; Thorn, C.B.
1995-12-31
The authors extend the model of string as a polymer of string bits to the case of superstring. They mainly concentrate on type II-B superstring, with some discussion of the obstacles presented by not II-B superstring, together with possible strategies for surmounting them. As with previous work on bosonic string work within the light-cone gauge. The bit model possesses a good deal less symmetry than the continuous string theory. For one thing, the bit model is formulated as a Galilei invariant theory in (D {minus} 2) + 1 dimensional space-time. This means that Poincare invariance is reduced to the Galilei subgroup in D {minus} 2 space dimensions. Naturally the supersymmetry present in the bit model is likewise dramatically reduced. Continuous string can arise in the bit models with the formation of infinitely long polymers of string bits. Under the right circumstances (at the critical dimension) these polymers can behave as string moving in D dimensional space-time enjoying the full N = 2 Poincare supersymmetric dynamics of type II-B superstring.
Energy Technology Data Exchange (ETDEWEB)
Jumarie, Guy E-mail: jumarie.guy@uqam.ca
2004-11-01
There are presently two different models of fractional Brownian motions available in the literature: the Riemann-Liouville fractional derivative of white noise on the one hand, and the complex-valued Brownian motion of order n defined by using a random walk in the complex plane, on the other hand. The paper provides a comparison between these two approaches, and in addition, takes this opportunity to contribute some complements. These two models are more or less equivalent on the theoretical standpoint for fractional order between 0 and 1/2, but their practical significances are quite different. Otherwise, for order larger than 1/2, the fractional derivative model has no counterpart in the complex plane. These differences are illustrated by an example drawn from mathematical finance. Taylor expansion of fractional order provides the expression of fractional difference in terms of finite difference, and this allows us to improve the derivation of Fokker-Planck equation and Kramers-Moyal expansion, and to get more insight in their relation with stochastic differential equations of fractional order. In the case of multi-fractal systems, the Fokker-Planck equation can be solved by using path integrals, and the fractional dynamic equations of the state moments of the stochastic system can be easily obtained. By combining fractional derivative and complex white noise of order n, one obtains a family of complex-valued fractional Brownian motions which exhibits long-range dependence. The conclusion outlines suggestions for further research, mainly regarding Lorentz transformation of fractional noises.
Bits and q-bits as versatility measures
Directory of Open Access Journals (Sweden)
José R.C. Piqueira
2004-06-01
Full Text Available Using Shannon information theory is a common strategy to measure any kind of variability in a signal or phenomenon. Some methods were developed to adapt information entropy measures to bird song data trying to emphasize its versatility aspect. This classical approach, using the concept of bit, produces interesting results. Now, the original idea developed in this paper is to use the quantum information theory and the quantum bit (q-bit concept in order to provide a more complete vision of the experimental results.Usar a teoria da informação de Shannon é uma estratégia comum para medir todo tipo de variabilidade em um sinal ou fenômeno. Alguns métodos foram desenvolvidos para adaptar a medida de entropia informacional a dados de cantos de pássaro, tentando enfatizar seus aspectos de versatilidade. Essa abordagem clássica, usando o conceito de bit, produz resultados interessantes. Agora, a idéia original desenvolvida neste artigo é usar a teoria quântica da informação e o conceito de q-bit, com a finalidade de proporcionar uma visão mais completa dos resultados experimentais.
A FAST BIT-LOADING ALGORITHM FOR HIGH SPEED POWER LINE COMMUNICATIONS
Institute of Scientific and Technical Information of China (English)
Zhang Shengqing; Zhao Li; Zou Cairong
2012-01-01
Adaptive bit-loading is a key technology in high speed power line communications with the Orthogonal Frequency Division Multiplexing (OFDM) modulation technology.According to the real situation of the transmitting power spectrum limited in high speed power line communications,this paper explored the adaptive bit loading algorithm to maximize transmission bit number when transmitting power spectral density and bit error rate are not exceed upper limit.With the characteristics of the power line channel,first of all,it obtains the optimal bit loading algorithm,and then provides the improved algorithm to reduce the computational complexity.Based on the analysis and simulation,it offers a non-iterative bit allocation algorithm,and finally the simulation shows that this new algorithm can greatly reduce the computational complexity,and the actual bit allocation results close to optimal.
Rate Control for MPEG-4 Bit Stream
Institute of Scientific and Technical Information of China (English)
王振洲; 李桂苓
2003-01-01
For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the processing and encoding operations is a set of visual elements organized in both time and space in a flexible and arbitrarily complex way. The moving picture experts group (MPEG-4) standard supports this concept and its verification model (VM) encoder has adopted scalable rate control (SRC) as the rate control scheme, which is based on the spatial domain and compatible with constant bit rate (CBR) and variable bit rate (VBR). In this paper,a new rate control algorithm based on the DCT domain instead of the pixel domain is presented. More-over, macroblock level rate control scheme to compute the quantization step for each macroblock has been adopted. The experimental results show that the new algorithm can achieve a much better result than the original one in both peak signal-to-noise ratio (PSNR) and the coding bits, and that the new algorithm is more flexible than test model 5 (TM5) rate control algorithm.
Energy Technology Data Exchange (ETDEWEB)
Noyes, H.P.
1990-01-29
We construct discrete space-time coordinates separated by the Lorentz-invariant intervals h/mc in space and h/mc{sup 2} in time using discrimination (XOR) between pairs of independently generated bit-strings; we prove that if this space is homogeneous and isotropic, it can have only 1, 2 or 3 spacial dimensions once we have related time to a global ordering operator. On this space we construct exact combinatorial expressions for free particle wave functions taking proper account of the interference between indistinguishable alternative paths created by the construction. Because the end-points of the paths are fixed, they specify completed processes; our wave functions are born collapsed''. A convenient way to represent this model is in terms of complex amplitudes whose squares give the probability for a particular set of observable processes to be completed. For distances much greater than h/mc and times much greater than h/mc{sup 2} our wave functions can be approximated by solutions of the free particle Dirac and Klein-Gordon equations. Using a eight-counter paradigm we relate this construction to scattering experiments involving four distinguishable particles, and indicate how this can be used to calculate electromagnetic and weak scattering processes. We derive a non-perturbative formula relating relativistic bound and resonant state energies to mass ratios and coupling constants, equivalent to our earlier derivation of the Bohr relativistic formula for hydrogen. Using the Fermi-Yang model of the pion as a relativistic bound state containing a nucleon-antinucleon pair, we find that (G{sub {pi}N}{sup 2}){sup 2} = (2m{sub N}/m{sub {pi}}){sup 2} {minus} 1. 21 refs., 1 fig.
A Holistic Approach to Bit Preservation
DEFF Research Database (Denmark)
Zierau, Eld Maj-Britt Olmütz
2011-01-01
This thesis presents three main results for a holistic approach to bit preservation, where the ultimate goal is to find the optimal bit preservation strategy for specific digital material that must be digitally preserved. Digital material consists of sequences of bits, where a bit is a binary dig...
Chuanshi Brand Tri-cone Roller Bit
Institute of Scientific and Technical Information of China (English)
Chen Xilong; Shen Zhenzhong; Yuan Xiaoyi
1997-01-01
@@ Compared with other types of bits, the tri-cone roller bit has the advantages of excellent comprehensive performance, low price, wide usage range. It is free of formation limits. The tri-cone roller bit accounts for 90% of the total bits in use. The Chengdu Mechanical Works, as a major manufacturer of petroleum mechanical products and one of the four major tri-cone roller bit factories in China,has produced 120 types of bits in seven series and 19 sizes since 1967. The bits manufactured by the factory are not only sold to the domestic oilfields, but also exported to Japan, Thailand, Indonesia, the Philippines and the Middle East.
Integer Representations towards Efficient Counting in the Bit Probe Model
DEFF Research Database (Denmark)
Brodal, Gerth Stølting; Greve, Mark; Pandey, Vineet
2011-01-01
Abstract We consider the problem of representing numbers in close to optimal space and supporting increment, decrement, addition and subtraction operations efficiently. We study the problem in the bit probe model and analyse the number of bits read and written to perform the operations, both...... in the worst-case and in the average-case. A counter is space-optimal if it represents any number in the range [0,...,2 n − 1] using exactly n bits. We provide a space-optimal counter which supports increment and decrement operations by reading at most n − 1 bits and writing at most 3 bits in the worst...... of the counter as the ratio between L + 1 and 2 n . We present various representations that achieve different trade-offs between the read and write complexities and the efficiency. We also give another representation of integers that uses n + O(logn ) bits to represent integers in the range [0,...,2 n − 1...
Classification system adopted for fixed cutter bits
Energy Technology Data Exchange (ETDEWEB)
Winters, W.J.; Doiron, H.H.
1988-01-01
The drilling industry has begun adopting the 1987 International Association of Drilling Contractors' (IADC) method for classifying fixed cutter drill bits. By studying the classification codes on bit records and properly applying the new IADC fixed cutter dull grading system to recently run bits, the end-user should be able to improve the selection and usage of fixed cutter bits. Several users are developing databases for fixed cutter bits in an effort to relate field performance to some of the more prominent bit design characteristics.
Flexible Bit Preservation on a National Basis
DEFF Research Database (Denmark)
Jurik, Bolette; Nielsen, Anders Bo; Zierau, Eld
2012-01-01
In this paper we present the results from The Danish National Bit Repository project. The project aim was establishment of a system that can offer flexible and sustainable bit preservation solutions to Danish cultural heritage institutions. Here the bit preservation solutions must include support...... of bit safety as well as other requirements like e.g. confidentiality and availability. The Danish National Bit Repository is motivated by the need to investigate and handle bit preservation for digital cultural heritage. Digital preservation relies on the integrity of the bits which digital material...... consists of, and it is with this focus that the project was initiated. This paper summarizes the requirements for a general system to offer bit preservation to cultural heritage institutions. On this basis the paper describes the resulting flexible system which can support such requirements. The paper...
Bit Serial Architecture for Variable Block Size Motion Estimation
Directory of Open Access Journals (Sweden)
Krishna Kaveri Devarinti
2013-06-01
Full Text Available H.264/AVC is the latest video coding standard adopting variable block size, quarter-pixel accuracy and motion vector prediction and multi-reference frames for motion estimations. These new features result in higher computation requirements than that for previous coding standards.The computational complexity of motion estimation is about 60% in the H.264/AVC encoder. In this paper most significant bit (MSB first arithmetic based bit serial Variable Block Size Motion Estimation (VBSME hardware architecture is proposed. MSB first bit serial architecture main feature is, its early termination SAD computation compared to normal bit serial architectures. With this early termination technique, number computations are reduced drastically. Hence power consumption is also less compared to parallel architectures. An efficient bit serial processing element is proposed and developed 2D architecture for processing of 4x4 block in parallel .Inter connect structure is developed in such way that data reusability is achieved between PEs. Two types of adder trees are employed for variable block size SAD calculation with less number of adders. The proposed architecture can generate up to 41 motion vectors (MVs for each macroblock. The inter connection complexity between PEs reduced drastically compared to parallel architectures. The architecture supports processing of SDTV (640x480 with 30fps at 172.8 MHz for search range [+8, -7]. We could reduce 14% of computations by using early termination technique.
24-Hour Relativistic Bit Commitment
Verbanis, Ephanielle; Martin, Anthony; Houlmann, Raphaël; Boso, Gianluca; Bussières, Félix; Zbinden, Hugo
2016-09-01
Bit commitment is a fundamental cryptographic primitive in which a party wishes to commit a secret bit to another party. Perfect security between mistrustful parties is unfortunately impossible to achieve through the asynchronous exchange of classical and quantum messages. Perfect security can nonetheless be achieved if each party splits into two agents exchanging classical information at times and locations satisfying strict relativistic constraints. A relativistic multiround protocol to achieve this was previously proposed and used to implement a 2-millisecond commitment time. Much longer durations were initially thought to be insecure, but recent theoretical progress showed that this is not so. In this Letter, we report on the implementation of a 24-hour bit commitment solely based on timed high-speed optical communication and fast data processing, with all agents located within the city of Geneva. This duration is more than 6 orders of magnitude longer than before, and we argue that it could be extended to one year and allow much more flexibility on the locations of the agents. Our implementation offers a practical and viable solution for use in applications such as digital signatures, secure voting and honesty-preserving auctions.
A brief review on quantum bit commitment
Almeida, Álvaro J.; Loura, Ricardo; Paunković, Nikola; Silva, Nuno A.; Muga, Nelson J.; Mateus, Paulo; André, Paulo S.; Pinto, Armando N.
2014-08-01
In classical cryptography, the bit commitment scheme is one of the most important primitives. We review the state of the art of bit commitment protocols, emphasizing its main achievements and applications. Next, we present a practical quantum bit commitment scheme, whose security relies on current technological limitations, such as the lack of long-term stable quantum memories. We demonstrate the feasibility of our practical quantum bit commitment protocol and that it can be securely implemented with nowadays technology.
Parity Bit Replenishment for JPEG 2000-Based Video Streaming
Directory of Open Access Journals (Sweden)
François-Olivier Devaux
2009-01-01
Full Text Available This paper envisions coding with side information to design a highly scalable video codec. To achieve fine-grained scalability in terms of resolution, quality, and spatial access as well as temporal access to individual frames, the JPEG 2000 coding algorithm has been considered as the reference algorithm to encode INTRA information, and coding with side information has been envisioned to refresh the blocks that change between two consecutive images of a video sequence. One advantage of coding with side information compared to conventional closed-loop hybrid video coding schemes lies in the fact that parity bits are designed to correct stochastic errors and not to encode deterministic prediction errors. This enables the codec to support some desynchronization between the encoder and the decoder, which is particularly helpful to adapt on the fly pre-encoded content to fluctuating network resources and/or user preferences in terms of regions of interest. Regarding the coding scheme itself, to preserve both quality scalability and compliance to the JPEG 2000 wavelet representation, a particular attention has been devoted to the definition of a practical coding framework able to exploit not only the temporal but also spatial correlation among wavelet subbands coefficients, while computing the parity bits on subsets of wavelet bit-planes. Simulations have shown that compared to pure INTRA-based conditional replenishment solutions, the addition of the parity bits option decreases the transmission cost in terms of bandwidth, while preserving access flexibility.
A holistic approach to bit preservation
DEFF Research Database (Denmark)
Zierau, Eld
2012-01-01
Purpose: The purpose of this paper is to point out the importance of taking a holistic approach to bit preservation when setting out to find an optimal bit preservation solution for specific digital materials. In the last decade there has been an increasing awareness that bit preservation, which ...
Directory of Open Access Journals (Sweden)
Borbon Martin de
2017-02-01
Full Text Available The goal of this article is to provide a construction and classification, in the case of two complex dimensions, of the possible tangent cones at points of limit spaces of non-collapsed sequences of Kähler-Einstein metrics with cone singularities. The proofs and constructions are completely elementary, nevertheless they have an intrinsic beauty. In a few words; tangent cones correspond to spherical metrics with cone singularities in the projective line by means of the Kähler quotient construction with respect to the S1-action generated by the Reeb vector field, except in the irregular case ℂβ₁×ℂβ₂ with β₂/ β₁ ∉ Q.
Fixed sagittal plane imbalance.
Savage, Jason W; Patel, Alpesh A
2014-12-01
Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.
BIT BY BIT: A Game Simulating Natural Language Processing in Computers
Kato, Taichi; Arakawa, Chuichi
2008-01-01
BIT BY BIT is an encryption game that is designed to improve students' understanding of natural language processing in computers. Participants encode clear words into binary code using an encryption key and exchange them in the game. BIT BY BIT enables participants who do not understand the concept of binary numbers to perform the process of…
Lee, Youngung; Jung, Jae-Hoon
2003-03-01
We have mapped the entire extent of the molecular cloud complex associated with NGC 281, both in 12CO ( J=1-0) and 13CO ( J=1-0), using the Taeduk Radio Astronomy Observatory (TRAO) 14 m telescope. We also observed a few selected fields with bright 13CO emission, in CS ( J=2-1) and HCO + ( J=1-0). This region is distinguished by its vertical height of ˜320 pc above the midplane of the Perseus spiral arm, at a distance of 2.9 kpc. The molecular gas in the mapped region is found to extend far beyond the H II region NGC 281 (Sh 184). The southern boundary of the CO emission closely follows the southern boundary of the 100 μm dust emission. The molecular cloud complex consists of two main clouds bisected by the H II region, as well as several other clouds distributed over a range of 90 pc along the galactic longitude direction. Except for one cloud at VLSR=-43.9 km s -1, all these clouds occupy a small, contiguous velocity range centered at VLSR=-30 km s -1. Although these clouds are weakly connected, they clearly show distinct, knotted features along the galactic longitude direction. We assigned names to each cloud (A-H), derive their various physical parameters, and discuss their physical properties. These clouds do not show any specific, systematic behavior in their velocity field, except for a small gradient along galactic longitude (for A-E). The brightest 12CO and 13CO emissions are detected toward cloud A, which is located farthest from the two main clouds. We found star formation to be ongoing in clouds A and B, though these are not as active as D and E. The associated newborn stars have FIR properties similar to those of Herbig Ae/Be stars, and several outflows are also seen. We estimated the cloud masses in three different ways, and discuss the discrepancies between the resulting values. We estimate the total mass of the mapped region to be ˜3.7×10 4 M ⊙, using a conversion factor from CO luminosity to gas mass. About half of the clouds seem to be
A Holistic Approach to Bit Preservation
DEFF Research Database (Denmark)
Zierau, Eld Maj-Britt Olmütz
2011-01-01
for confidentiality, availability, costs, additional to the requirements of ensuring bit safety. A few examples are: • The way that digital material is represented in files and structures has an influence on whether it is possible to interpret and use the bits at a later stage. Consequentially, the way bits represent....... • There will be requirements for the availability of the bit preserved digital material in order to meet requirements on use of the digital material, e.g. libraries often need to give fast access to preserved digital material to the public, i.e. the availability of the bit preserved material must support the use...
Designing embedded systems with 32-bit PIC microcontrollers and MikroC
Ibrahim, Dogan
2013-01-01
The new generation of 32-bit PIC microcontrollers can be used to solve the increasingly complex embedded system design challenges faced by engineers today. This book teaches the basics of 32-bit C programming, including an introduction to the PIC 32-bit C compiler. It includes a full description of the architecture of 32-bit PICs and their applications, along with coverage of the relevant development and debugging tools. Through a series of fully realized example projects, Dogan Ibrahim demonstrates how engineers can harness the power of this new technology to optimize their embedded design
Advanced approaches to the improving of three-cone rock bits manufacturing method
Яким, Роман; Петрина, Юрій; Яким, Ігор
2013-01-01
The complex approach to the improvement of three-cone rock bits manufacturing method, that includes the requirements increase for the chemical composition of rock bit steels, and also the advanced approaches to the improvement of technological processes quality and efficiency are offered.
Stability of single skyrmionic bits
Vedmedenko, Olena; Hagemeister, Julian; Romming, Niklas; von Bergmann, Kirsten; Wiesendanger, Roland
The switching between topologically distinct skyrmionic and ferromagnetic states has been proposed as a bit operation for information storage. While long lifetimes of the bits are required for data storage devices, the lifetimes of skyrmions have not been addressed so far. Here we show by means of atomistic Monte Carlo simulations that the field-dependent mean lifetimes of the skyrmionic and ferromagnetic states have a high asymmetry with respect to the critical magnetic field, at which these lifetimes are identical. According to our calculations, the main reason for the enhanced stability of skyrmions is a different field dependence of skyrmionic and ferromagnetic activation energies and a lower attempt frequency of skyrmions rather than the height of energy barriers. We use this knowledge to propose a procedure for the determination of effective material parameters and the quantification of the Monte Carlo timescale from the comparison of theoretical and experimental data. Financial support from the DFG in the framework of the SFB668 is acknowledged.
Bit threads and holographic entanglement
Freedman, Michael
2016-01-01
The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner...
DEFF Research Database (Denmark)
Sabra, Jakob Borrits
We mourn our dead, publicly and privately, online and offline. Cemeteries, web memorials and social network sites make up parts of todays intricately weaved and interrelated network of death, grief and memorialization practices [1]–[5]. Whether cut in stone or made of bits, graves, cemeteries, me...... and memorialization by discussing the publicly and privately digital and social death from a spatial, temporal, physical and digital angle. Further the paper will reflect on how to encompass shifting trends and technologies in ‘traditional’ spaces of mourning and remembrance.......We mourn our dead, publicly and privately, online and offline. Cemeteries, web memorials and social network sites make up parts of todays intricately weaved and interrelated network of death, grief and memorialization practices [1]–[5]. Whether cut in stone or made of bits, graves, cemeteries......, memorials, monuments, websites and social networking services (SNS) all are alterable, controllable and adaptive. They represent a certain rationale contrary to the emotive state of mourning (e.g. gravesites function as both spaces of internment and places of spiritual and emotional recollection). Following...
Bit Threads and Holographic Entanglement
Freedman, Michael; Headrick, Matthew
2016-11-01
The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner to the properties' information-theoretic meanings. We also briefly discuss certain technical advantages that the flows offer over minimal surfaces. In a mathematical appendix, we review the max flow-min cut theorem on networks and on Riemannian manifolds, and prove in the network case that the set of max flows varies Lipshitz continuously in the network parameters.
A Symmetric Chaos-Based Image Cipher with an Improved Bit-Level Permutation Strategy
Directory of Open Access Journals (Sweden)
Chong Fu
2014-02-01
Full Text Available Very recently, several chaos-based image ciphers using a bit-level permutation have been suggested and shown promising results. Due to the diffusion effect introduced in the permutation stage, the workload of the time-consuming diffusion stage is reduced, and hence the performance of the cryptosystem is improved. In this paper, a symmetric chaos-based image cipher with a 3D cat map-based spatial bit-level permutation strategy is proposed. Compared with those recently proposed bit-level permutation methods, the diffusion effect of the new method is superior as the bits are shuffled among different bit-planes rather than within the same bit-plane. Moreover, the diffusion key stream extracted from hyperchaotic system is related to both the secret key and the plain image, which enhances the security against known/chosen plaintext attack. Extensive security analysis has been performed on the proposed scheme, including the most important ones like key space analysis, key sensitivity analysis, plaintext sensitivity analysis and various statistical analyses, which has demonstrated the satisfactory security of the proposed scheme
Directory of Open Access Journals (Sweden)
Moyocoyani Molina-Espíritu
2013-09-01
Full Text Available An information-theoretical complexity analysis of the SN2 exchange reaction for CH3Cl + F− is performed in both position and momentum spaces by means of the following composite functionals of the one-particle density: D-L and I-J planes and Fisher-Shannon’s (FS and López-Ruiz-Mancini-Calbet (LMC shape complexities. It was found that all the chemical concepts traditionally assigned to elementary reactions such as the breaking/forming regions (B-B/F, the charge transfer/reorganization and the charge repulsion can be unraveled from the phenomenological analysis performed in this study through aspects of localizability, uniformity and disorder associated with the information-theoretical functionals. In contrast, no energy-based functionals can reveal the above mentioned chemical concepts. In addition, it is found that the TS critical point for this reaction does not show any chemical meaning (other than the barrier height as compared with the concurrent processes revealed by the information-theoretical analysis. Instead, it is apparent from this study that a maximum delocalized state could be identified in the transition region which is associated to the charge transfer process as a new concurrent phenomenon associated with the charge transfer region (CT for the ion-complex is identified. Finally it is discussed why most of the chemical features of interest (e.g., CT, B-B/F are only revealed when some information-theoretic properties are taken into account, such as localizability, uniformity and disorder.
Reading boundless error-free bits using a single photon
Guha, Saikat; Shapiro, Jeffrey H.
2013-06-01
We address the problem of how efficiently information can be encoded into and read out reliably from a passive reflective surface that encodes classical data by modulating the amplitude and phase of incident light. We show that nature imposes no fundamental upper limit to the number of bits that can be read per expended probe photon and demonstrate the quantum-information-theoretic trade-offs between the photon efficiency (bits per photon) and the encoding efficiency (bits per pixel) of optical reading. We show that with a coherent-state (ideal laser) source, an on-off (amplitude-modulation) pixel encoding, and shot-noise-limited direct detection (an overly optimistic model for commercial CD and DVD drives), the highest photon efficiency achievable in principle is about 0.5 bits read per transmitted photon. We then show that a coherent-state probe can read unlimited bits per photon when the receiver is allowed to make joint (inseparable) measurements on the reflected light from a large block of phase-modulated memory pixels. Finally, we show an example of a spatially entangled nonclassical light probe and a receiver design—constructible using a single-photon source, beam splitters, and single-photon detectors—that can in principle read any number of error-free bits of information. The probe is a single photon prepared in a uniform coherent superposition of multiple orthogonal spatial modes, i.e., a W state. The code and joint-detection receiver complexity required by a coherent-state transmitter to achieve comparable photon efficiency performance is shown to be much higher in comparison to that required by the W-state transceiver, although this advantage rapidly disappears with increasing loss in the system.
DEFF Research Database (Denmark)
Sabra, Jakob Borrits; Andersen, Hans Jørgen
The digital spheres of Information and Communication Technologies (ICT) and Social Network Services (SNS) are influencing 21st. century death. Today the dying and the bereaved attend mourning and remembrance both online and offline. Combined, the cemeteries, web memorials and social network sites...... designs'. Urns, coffins, graves, cemeteries, memorials, monuments, websites, applications and software services, whether cut in stone or made of bits, are all influenced by discourses of publics, economics, power, technology and culture. Designers, programmers, stakeholders and potential end-users often...... do not recognize the need or potential of working with or using, specific 'death-services/products', since they find little or no comfort in contemplating, working or playing around with the concept of death and its life changing consequences. Especially not while being alive and well...
Energy Technology Data Exchange (ETDEWEB)
Wu, Kesheng
2007-08-02
An index in a database system is a data structure that utilizes redundant information about the base data to speed up common searching and retrieval operations. Most commonly used indexes are variants of B-trees, such as B+-tree and B*-tree. FastBit implements a set of alternative indexes call compressed bitmap indexes. Compared with B-tree variants, these indexes provide very efficient searching and retrieval operations by sacrificing the efficiency of updating the indexes after the modification of an individual record. In addition to the well-known strengths of bitmap indexes, FastBit has a special strength stemming from the bitmap compression scheme used. The compression method is called the Word-Aligned Hybrid (WAH) code. It reduces the bitmap indexes to reasonable sizes and at the same time allows very efficient bitwise logical operations directly on the compressed bitmaps. Compared with the well-known compression methods such as LZ77 and Byte-aligned Bitmap code (BBC), WAH sacrifices some space efficiency for a significant improvement in operational efficiency. Since the bitwise logical operations are the most important operations needed to answer queries, using WAH compression has been shown to answer queries significantly faster than using other compression schemes. Theoretical analyses showed that WAH compressed bitmap indexes are optimal for one-dimensional range queries. Only the most efficient indexing schemes such as B+-tree and B*-tree have this optimality property. However, bitmap indexes are superior because they can efficiently answer multi-dimensional range queries by combining the answers to one-dimensional queries.
Stinger Enhanced Drill Bits For EGS
Energy Technology Data Exchange (ETDEWEB)
Durrand, Christopher J. [Novatek International, Inc., Provo, UT (United States); Skeem, Marcus R. [Novatek International, Inc., Provo, UT (United States); Crockett, Ron B. [Novatek International, Inc., Provo, UT (United States); Hall, David R. [Novatek International, Inc., Provo, UT (United States)
2013-04-29
The project objectives were to design, engineer, test, and commercialize a drill bit suitable for drilling in hard rock and high temperature environments (10,000 meters) likely to be encountered in drilling enhanced geothermal wells. The goal is provide a drill bit that can aid in the increased penetration rate of three times over conventional drilling. Novatek has sought to leverage its polycrystalline diamond technology and a new conical cutter shape, known as the Stinger®, for this purpose. Novatek has developed a fixed bladed bit, known as the JackBit®, populated with both shear cutter and Stingers that is currently being tested by major drilling companies for geothermal and oil and gas applications. The JackBit concept comprises a fixed bladed bit with a center indenter, referred to as the Jack. The JackBit has been extensively tested in the lab and in the field. The JackBit has been transferred to a major bit manufacturer and oil service company. Except for the attached published reports all other information is confidential.
Bit-coded regular expression parsing
DEFF Research Database (Denmark)
Nielsen, Lasse; Henglein, Fritz
2011-01-01
Regular expression parsing is the problem of producing a parse tree of a string for a given regular expression. We show that a compact bit representation of a parse tree can be produced efficiently, in time linear in the product of input string size and regular expression size, by simplifying...... the DFA-based parsing algorithm due to Dub ´e and Feeley to emit the bits of the bit representation without explicitly materializing the parse tree itself. We furthermore show that Frisch and Cardelli’s greedy regular expression parsing algorithm can be straightforwardly modified to produce bit codings...
A family of compatible single- and multimicroprocessor systems with 8-bit and 16-bit Microprocessors
Energy Technology Data Exchange (ETDEWEB)
Brzezinski, J.; Cellary, W.; Kreglewski, J.
1984-10-01
In the paper, a multimicroprocessor system for 8-bit and 16-bit microprocessors is presented. The main assumptions of the project of the presented system are discussed. Different single- and multimicroprocessor structures with 8-bit microprocessors are outlined. A detailed description of two single-board microcomputers and system aspects of different solutions are presented. Finally, an intelligent floppy disk controller is described.
Ba, Zhenning; Yin, Xiao
2016-06-01
A multidomain indirect boundary element method (IBEM) is proposed to study the wave scattering of plane SH waves by complex local site in a layered half-space. The new method, using both the full-space and layered half-space Green's functions as its fundamental solutions can also be regarded as a coupled method of the full-space IBEM and half-space IBEM. First, the whole model is decomposed into independent closed regions and an opened layered half-space region with all of the irregular interfaces; then, fictitious uniformly distributed loads are applied separately on the boundaries of each region, and scattered fields of the closed regions and the opened layered half-space region are constructed by calculating the full-space and layered half-space Green's functions, respectively; finally, all of the regions are assembled to establish the linear algebraic system that arises from discretization. The densities of the distributed loads are determined directly by solving the algebraic system. The accuracy and capability of the new approach are verified extensively by comparing its results with those of published approaches for a class of hills, valleys and embedded inclusions. And the capability of the new method is further displayed when it is used to investigate a hill-triple layered valley-hill coupled topography in a multilayered half-space. All of the numerical calculations presented in this paper demonstrate that the new method is very suitable for solving multidomain coupled multilayered wave scattering problems with the merits of high accuracy and representing the scattered fields in different kinds of regions more reasonably and flexibly.
Luo, B.; Duan, B.
2015-12-01
The Mw 9.0 Tohoku megathrust earthquake on 11 March 2011 is a great surprise to the scientific community due to its unexpected occurrence on the subduction zone of Japan Trench where earthquakes of magnitude ~7 to 8 are expected based on historical records. Slip distribution and kinematic slip history inverted from seismic data, GPS and tsunami recordings reveal two major aspects of this big event: a strong asperity near the hypocenter and large slip near the trench. To investigate physical conditions of these two aspects, we perform dynamic rupture simulations on a shallow-dipping rate- and state-dependent subduction plane with topographic relief. Although existence of a subducted seamount just up-dip of the hypocenter is still an open question, high Vp anomalies [Zhao et al., 2011] and low Vp/Vs anomalies [Yamamoto et al., 2014] there strongly suggest some kind of topographic relief exists there. We explicitly incorporate a subducted seamount on the subduction surface into our models. Our preliminary results show that the subducted seamount play a significant role in dynamic rupture propagation due to the alteration of the stress state around it. We find that a subducted seamount can act as a strong barrier to many earthquakes, but its ultimate failure after some earthquake cycles results in giant earthquakes. Its failure gives rise to large stress drop, resulting in a strong asperity in slip distribution as revealed in kinematic inversions. Our preliminary results also suggest that the rate- and state- friction law plays an important role in rupture propagation of geometrically complex faults. Although rate-strengthening behavior near the trench impedes rupture propagation, an energetic rupture can break such a barrier and manage to reach the trench, resulting in significant uplift at seafloor and hence devastating tsunami to human society.
PERBANDINGAN APLIKASI MENGGUNAKAN METODE CAMELLIA 128 BIT KEY DAN 256 BIT KEY
Directory of Open Access Journals (Sweden)
Lanny Sutanto
2014-01-01
Full Text Available The rapid development of the Internet today to easily exchange data. This leads to high levels of risk in the data piracy. One of the ways to secure data is using cryptography camellia. Camellia is known as a method that has the encryption and decryption time is fast. Camellia method has three kinds of scale key is 128 bit, 192 bit, and 256 bit.This application is created using the C++ programming language and using visual studio 2010 GUI. This research compare the smallest and largest key size used on the file extension .Txt, .Doc, .Docx, .Jpg, .Mp4, .Mkv and .Flv. This application is made to comparing time and level of security in the use of 128-bit key and 256 bits. The comparison is done by comparing the results of the security value of avalanche effect 128 bit key and 256 bit key.
A holistic approach to bit preservation
DEFF Research Database (Denmark)
Zierau, Eld
2012-01-01
Purpose: The purpose of this paper is to point out the importance of taking a holistic approach to bit preservation when setting out to find an optimal bit preservation solution for specific digital materials. In the last decade there has been an increasing awareness that bit preservation, which...... preservation strategies as well as pointing to how such strategies can be evaluated. Research limitations/implications The operational results described here are still missing work to be fully operational. However, the holistic approach is in itself an important result. Furthermore, in spite...
基于复合相量平面的自适应过负荷识别方法%Complex Phasor Plane Based Adaptive Overload Identification
Institute of Scientific and Technical Information of China (English)
马静; 王卓; 马伟; 王增平; 王思源; 林祺蓉; 张同乔; 张德伟
2014-01-01
针对本地距离保护III段易受事故过负荷影响导致误动的问题，提出了一种基于复合相量平面的自适应过负荷识别方法。首先根据不同运行工况下量测相量的几何分布特性，建立虚拟电压降落方程，并据此求解自适应整定系数的计算公式，构造距离保护III段自适应过负荷识别判据，然后，将该判据与传统距离保护III段的动作特性相结合，以识别过负荷与对称故障。IEEE 10机39节点系统仿真结果验证了该方法一方面可避免由于过负荷引发的距离保护 III段误动情况的发生，另一方面，在过负荷又出现对称故障情况下，仍能有效发挥后备保护的作用。%ABSTRACT:The zone 3 of local distance protection is easy to be affected by incident overload and it leads to the malfunction. To overcome this defect, a complex phasor plane based adaptive overload identification method is proposed. Firstly, according to geometrical distribution of phasors measured under different operating conditions, the virtual voltage drop equation is established and on this basis the computing formula of adaptive setting coefficients is derived to construct the criterion of adaptively identifying the overload for the zone 3 of distance protection;then this criterion is combined with the action characteristic of zone 3 of distance protection to distinguish overload from symmetrical fault. Using the proposed method, on the one hand, the malfunction of the zone 3 of distance protection, which is caused by overload, can be avoided, on the other hand, under such a condition that the overload is accompanying with symmetrical fault the zone 3 of distance protection can still play a role of backup protection effectively. The correctness of the proposed method is validated by IEEE 10-machine 39-bus system.
FastBit: Interactively Searching Massive Data
Energy Technology Data Exchange (ETDEWEB)
Wu, Kesheng; Ahern, Sean; Bethel, E. Wes; Chen, Jacqueline; Childs, Hank; Cormier-Michel, Estelle; Geddes, Cameron; Gu, Junmin; Hagen, Hans; Hamann, Bernd; Koegler, Wendy; Lauret, Jerome; Meredith, Jeremy; Messmer, Peter; Otoo, Ekow; Perevoztchikov, Victor; Poskanzer, Arthur; Prabhat,; Rubel, Oliver; Shoshani, Arie; Sim, Alexander; Stockinger, Kurt; Weber, Gunther; Zhang, Wei-Ming
2009-06-23
As scientific instruments and computer simulations produce more and more data, the task of locating the essential information to gain insight becomes increasingly difficult. FastBit is an efficient software tool to address this challenge. In this article, we present a summary of the key underlying technologies, namely bitmap compression, encoding, and binning. Together these techniques enable FastBit to answer structured (SQL) queries orders of magnitude faster than popular database systems. To illustrate how FastBit is used in applications, we present three examples involving a high-energy physics experiment, a combustion simulation, and an accelerator simulation. In each case, FastBit significantly reduces the response time and enables interactive exploration on terabytes of data.
An optical ultrafast random bit generator
Kanter, Ido; Aviad, Yaara; Reidler, Igor; Cohen, Elad; Rosenbluh, Michael
2010-01-01
The generation of random bit sequences based on non-deterministic physical mechanisms is of paramount importance for cryptography and secure communications. High data rates also require extremely fast generation rates and robustness to external perturbations. Physical generators based on stochastic noise sources have been limited in bandwidth to ~100 Mbit s-1 generation rates. We present a physical random bit generator, based on a chaotic semiconductor laser, having time-delayed self-feedback, which operates reliably at rates up to 300 Gbit s-1. The method uses a high derivative of the digitized chaotic laser intensity and generates the random sequence by retaining a number of the least significant bits of the high derivative value. The method is insensitive to laser operational parameters and eliminates the necessity for all external constraints such as incommensurate sampling rates and laser external cavity round trip time. The randomness of long bit strings is verified by standard statistical tests.
The Braid-Based Bit Commitment Protocol
Institute of Scientific and Technical Information of China (English)
WANG Li-cheng; CAO Zhen-fu; CAO Feng; QIAN Hai-feng
2006-01-01
With recent advances of quantum computation, new threats have closed in upon to the classical public key cryptosystems. In order to build more secure bit commitment schemes, this paper gave a survey of the new coming braid-based cryptography and then brought forward the first braid-based bit commitment protocol. The security proof manifests that the proposed protocol is computationally binding and information-theoretically hiding.Furthermore, the proposed protocol is also invulnerable to currently known quantum attacks.
Neural network implementation using bit streams.
Patel, Nitish D; Nguang, Sing Kiong; Coghill, George G
2007-09-01
A new method for the parallel hardware implementation of artificial neural networks (ANNs) using digital techniques is presented. Signals are represented using uniformly weighted single-bit streams. Techniques for generating bit streams from analog or multibit inputs are also presented. This single-bit representation offers significant advantages over multibit representations since they mitigate the fan-in and fan-out issues which are typical to distributed systems. To process these bit streams using ANNs concepts, functional elements which perform summing, scaling, and squashing have been implemented. These elements are modular and have been designed such that they can be easily interconnected. Two new architectures which act as monotonically increasing differentiable nonlinear squashing functions have also been presented. Using these functional elements, a multilayer perceptron (MLP) can be easily constructed. Two examples successfully demonstrate the use of bit streams in the implementation of ANNs. Since every functional element is individually instantiated, the implementation is genuinely parallel. The results clearly show that this bit-stream technique is viable for the hardware implementation of a variety of distributed systems and for ANNs in particular.
Kumar, Santosh; Bisht, Ashish; Singh, Gurdeep; Choudhary, Kuldeep; Raina, K. K.; Amphawan, Angela
2015-12-01
The Mach-Zehnder interferometer (MZI) structures collectively show powerful capability in switching an input optical signal to a desired output port from a collection of output ports. Hence, it is possible to construct complex optical combinational digital circuits using the electro-optic effect constituting MZI structure as a basic building block. Optical switches have been designed for 1-bit and 2-bit magnitude comparators based on electro-optic effect using Mach-Zehnder interferometers. The paper constitutes a mathematical description of the proposed device and thereafter simulation using MATLAB. Analysis of some factors influencing the performances of proposed device has been discussed properly. The study is verified using beam propagation method.
Oss, Stefano; Rosi, Tommaso
2015-01-01
We have developed an app for iOS-based smart-phones/tablets that allows a 3-D, complex phase-based colorful visualization of hydrogen atom wave functions. Several important features of the quantum behavior of atomic orbitals can easily be made evident, thus making this app a useful companion in introductory modern physics classes. There are many…
Oss, Stefano; Rosi, Tommaso
2015-01-01
We have developed an app for iOS-based smart-phones/tablets that allows a 3-D, complex phase-based colorful visualization of hydrogen atom wave functions. Several important features of the quantum behavior of atomic orbitals can easily be made evident, thus making this app a useful companion in introductory modern physics classes. There are many…
Directory of Open Access Journals (Sweden)
Albertus C. den Brinker
2007-01-01
Full Text Available This paper introduces a new audio and speech broadband coding technique based on the combination of a pulse excitation coder and a standardized parametric coder, namely, MPEG-4 high-quality parametric coder. After presenting a series of enhancements to regular pulse excitation (RPE to make it suitable for the modeling of broadband signals, it is shown how pulse and parametric codings complement each other and how they can be merged to yield a layered bit stream scalable coder able to operate at different points in the quality bit rate plane. The performance of the proposed coder is evaluated in a listening test. The major result is that the extra functionality of the bit stream scalability does not come at the price of a reduced performance since the coder is competitive with standardized coders (MP3, AAC, SSC.
Transversals of Complex Polynomial Vector Fields
DEFF Research Database (Denmark)
Dias, Kealey
, an important step was proving that the transversals possessed a certain characteristic. Understanding transversals might be the key to proving other polynomial vector fields are generic, and they are important in understanding bifurcations of polynomial vector fields in general. We consider two important......Vector fields in the complex plane are defined by assigning the vector determined by the value P(z) to each point z in the complex plane, where P is a polynomial of one complex variable. We consider special families of so-called rotated vector fields that are determined by a polynomial multiplied...... a concrete polynomial, it seems to take quite a bit of work to prove that it is generic, i.e. structurally stable. This has been done for a special class of degree d polynomial vector fields having simple equilibrium points at the d roots of unity, d odd. In proving that such vector fields are generic...
Atomistic simulation of static magnetic properties of bit patterned media
Arbeláez-Echeverri, O. D.; Agudelo-Giraldo, J. D.; Restrepo-Parra, E.
2016-09-01
In this work we present a new design of Co based bit pattern media with out-of-plane uni-axial anisotropy induced by interface effects. Our model features the inclusion of magnetic impurities in the non-magnetic matrix. After the material model was refined during three iterations using Monte Carlo simulations, further simulations were performed using an atomistic integrator of Landau-Lifshitz-Gilbert equation with Langevin dynamics to study the behavior of the system paying special attention to the super-paramagnetic limit. Our model system exhibits three magnetic phase transitions, one due to the magnetically doped matrix material and the weak magnetic interaction between the nano-structures in the system. The different magnetic phases of the system as well as the features of its phase diagram are explained.
Ultra low bit-rate speech coding
Ramasubramanian, V
2015-01-01
"Ultra Low Bit-Rate Speech Coding" focuses on the specialized topic of speech coding at very low bit-rates of 1 Kbits/sec and less, particularly at the lower ends of this range, down to 100 bps. The authors set forth the fundamental results and trends that form the basis for such ultra low bit-rates to be viable and provide a comprehensive overview of various techniques and systems in literature to date, with particular attention to their work in the paradigm of unit-selection based segment quantization. The book is for research students, academic faculty and researchers, and industry practitioners in the areas of speech processing and speech coding.
Oss, Stefano; Rosi, Tommaso
2015-04-01
We have developed an app for iOS-based smart-phones/tablets that allows a 3-D, complex phase-based colorful visualization of hydrogen atom wave functions. Several important features of the quantum behavior of atomic orbitals can easily be made evident, thus making this app a useful companion in introductory modern physics classes. There are many reasons why quantum mechanical systems and phenomena are difficult both to teach and deeply understand. They are described by equations that are generally hard to visualize, and they often oppose the so-called "common sense" based on the human perception of the world, which is built on mental images such as locality and causality. Moreover students cannot have direct experience of those systems and solutions, and generally do not even have the possibility to refer to pictures, videos, or experiments to fill this gap. Teachers often encounter quite serious troubles in finding out a sensible way to speak about the wonders of quantum physics at the high school level, where complex formalisms are not accessible at all. One should however consider that this is quite a common issue in physics and, more generally, in science education. There are plenty of natural phenomena whose models (not only at microscopic and atomic levels) are of difficult, if not impossible, visualization. Just think of certain kinds of waves, fields of forces, velocities, energy, angular momentum, and so on. One should also notice that physical reality is not the same as the images we make of it. Pictures (formal, abstract ones, as well as artists' views) are a convenient bridge between these two aspects.
BSSSN: Bit String Swapping Sorting Network for Reversible Logic Synthesis
Islam, Md Saiful
2010-01-01
In this paper, we have introduced the notion of UselessGate and ReverseOperation. We have also given an algorithm to implement a sorting network for reversible logic synthesis based on swapping bit strings. The network is constructed in terms of n*n Toffoli Gates read from left to right and it has shown that there will be no more gates than the number of swappings the algorithm requires. The gate complexity of the network is O(n2). The number of gates in the network can be further reduced by template reduction technique and removing UselessGate from the network.
Protected Polycrystalline Diamond Compact Bits For Hard Rock Drilling
Energy Technology Data Exchange (ETDEWEB)
Robert Lee Cardenas
2000-10-31
Two bits were designed. One bit was fabricated and tested at Terra-Tek's Drilling Research Laboratory. Fabrication of the second bit was not completed due to complications in fabrication and meeting scheduled test dates at the test facility. A conical bit was tested in a Carthage Marble (compressive strength 14,500 psi) and Sierra White Granite (compressive strength 28,200 psi). During the testing, Hydraulic Horsepower, Bit Weight, Rotation Rate, were varied for the Conical Bit, a Varel Tricone Bit and Varel PDC bit. The Conical Bi did cut rock at a reasonable rate in both rocks. Beneficial effects from the near and through cutter water nozzles were not evident in the marble due to test conditions and were not conclusive in the granite due to test conditions. At atmospheric drilling, the Conical Bit's penetration rate was as good as the standard PDC bit and better than the Tricone Bit. Torque requirements for the Conical Bit were higher than that required for the Standard Bits. Spudding the conical bit into the rock required some care to avoid overloading the nose cutters. The nose design should be evaluated to improve the bit's spudding characteristics.
Linear, Constant-rounds Bit-decomposition
DEFF Research Database (Denmark)
Reistad, Tord; Toft, Tomas
2010-01-01
When performing secure multiparty computation, tasks may often be simple or difficult depending on the representation chosen. Hence, being able to switch representation efficiently may allow more efficient protocols. We present a new protocol for bit-decomposition: converting a ring element x ∈ ℤ M...
1 /N perturbations in superstring bit models
Thorn, Charles B.
2016-03-01
We develop the 1 /N expansion for stable string bit models, focusing on a model with bit creation operators carrying only transverse spinor indices a =1 ,…,s . At leading order (N =∞ ), this model produces a (discretized) light cone string with a "transverse space" of s Grassmann worldsheet fields. Higher orders in the 1 /N expansion are shown to be determined by the overlap of a single large closed chain (discretized string) with two smaller closed chains. In the models studied here, the overlap is not accompanied with operator insertions at the break/join point. Then, the requirement that the discretized overlap has a smooth continuum limit leads to the critical Grassmann "dimension" of s =24 . This "protostring," a Grassmann analog of the bosonic string, is unusual, because it has no large transverse dimensions. It is a string moving in one space dimension, and there are neither tachyons nor massless particles. The protostring, derived from our pure spinor string bit model, has 24 Grassmann dimensions, 16 of which could be bosonized to form 8 compactified bosonic dimensions, leaving 8 Grassmann dimensions—the worldsheet content of the superstring. If the transverse space of the protostring could be "decompactified," string bit models might provide an appealing and solid foundation for superstring theory.
Reinforcement Learning in BitTorrent Systems
Izhak-Ratzin, Rafit; van der Schaar, Mihaela
2010-01-01
Recent research efforts have shown that the popular BitTorrent protocol does not provide fair resource reciprocation and may allow free-riding. In this paper, we propose a BitTorrent-like protocol that replaces the peer selection mechanisms in the regular BitTorrent protocol with a novel reinforcement learning (RL) based mechanism. Due to the inherent opration of P2P systems, which involves repeated interactions among peers over a long period of time, the peers can efficiently identify free-riders as well as desirable collaborators by learning the behavior of their associated peers. Thus, it can help peers improve their download rates and discourage free-riding, while improving fairness in the system. We model the peers' interactions in the BitTorrent-like network as a repeated interaction game, where we explicitly consider the strategic behavior of the peers. A peer, which applies the RL-based mechanism, uses a partial history of the observations on associated peers' statistical reciprocal behaviors to deter...
Hey! A Mosquito Bit Me! (For Kids)
... or Too Short All About Puberty Hey! A Mosquito Bit Me! KidsHealth > For Kids > Hey! A Mosquito ... español ¡Ay! ¡Me picó un mosquito! What's a Mosquito? A mosquito (say: mus-KEE-toe) is an ...
Bit corruption correlation and autocorrelation in a stochastic binary nano-bit system
Sa-nguansin, Suchittra
2014-10-01
The corruption process of a binary nano-bit model resulting from an interaction with N stochastically-independent Brownian agents (BAs) is studied with the help of Monte-Carlo simulations and analytic continuum theory to investigate the data corruption process through the measurement of the spatial two-point correlation and the autocorrelation of bit corruption at the origin. By taking into account a more realistic correlation between bits, this work will contribute to the understanding of the soft error or the corruption of data stored in nano-scale devices.
Fixed Sagittal Plane Imbalance
Savage, Jason W.; Patel, Alpesh A.
2014-01-01
Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is ...
Energy Technology Data Exchange (ETDEWEB)
Sargent, M. T.; Daddi, E.; Béthermin, M.; Aussel, H.; Juneau, S.; Elbaz, D. [CEA Saclay, DSM/Irfu/Sérvice d' Astrophysique, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Magdis, G. [Department of Physics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom); Hwang, H. S. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Da Cunha, E., E-mail: mark.sargent@cea.fr [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)
2014-09-20
Star-forming galaxies (SFGs) display a continuous specific star formation rate (sSFR) distribution, which can be approximated by two log-normal functions: one encompassing the galaxy main sequence (MS), and the other a rarer, starbursting population. Starburst (SB) sSFRs can be regarded as the outcome of a physical process (plausibly merging) taking the mathematical form of a log-normal boosting kernel that enhances star formation activity. We explore the utility of splitting the star-forming population into MS and SB galaxies—an approach we term the '2-Star Formation Mode' framework—for understanding their molecular gas properties. Star formation efficiency (SFE) and gas fraction variations among SFGs take a simple redshift-independent form, once these quantities are normalized to the corresponding values for average MS galaxies. SFE enhancements during SB episodes scale supra-linearly with the SFR increase, as expected for mergers. Consequently, galaxies separate more clearly into loci for SBs and normal galaxies in the Schmidt-Kennicutt plane than in (s)SFR versus M {sub *} space. SBs with large deviations (>10 fold) from the MS, e.g., local ULIRGs, are not average SBs, but are much rarer events whose progenitors had larger gas fractions than typical MS galaxies. Statistically, gas fractions in SBs are reduced two- to threefold compared to their direct MS progenitors, as expected for short-lived SFR boosts where internal gas reservoirs are depleted more quickly than gas is re-accreted from the cosmic web. We predict variations of the conversion factor α{sub CO} in the SFR-M {sub *} plane and we show that the higher sSFR of distant galaxies is directly related to their larger gas fractions.
Energy Technology Data Exchange (ETDEWEB)
Modeste Nguimdo, Romain, E-mail: Romain.Nguimdo@vub.ac.be [Applied Physics Research Group, APHY, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel (Belgium); Tchitnga, Robert [Laboratory of Electronics, Automation and Signal Processing, Department of Physics, University of Dschang, P.O. Box 67, Dschang (Cameroon); Woafo, Paul [Laboratory of Modelling and Simulation in Engineering and Biological Physics, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé (Cameroon)
2013-12-15
We numerically investigate the possibility of using a coupling to increase the complexity in simplest chaotic two-component electronic circuits operating at high frequency. We subsequently show that complex behaviors generated in such coupled systems, together with the post-processing are suitable for generating bit-streams which pass all the NIST tests for randomness. The electronic circuit is built up by unidirectionally coupling three two-component (one active and one passive) oscillators in a ring configuration through resistances. It turns out that, with such a coupling, high chaotic signals can be obtained. By extracting points at fixed interval of 10 ns (corresponding to a bit rate of 100 Mb/s) on such chaotic signals, each point being simultaneously converted in 16-bits (or 8-bits), we find that the binary sequence constructed by including the 10(or 2) least significant bits pass statistical tests of randomness, meaning that bit-streams with random properties can be achieved with an overall bit rate up to 10×100 Mb/s =1Gbit/s (or 2×100 Mb/s =200 Megabit/s). Moreover, by varying the bias voltages, we also investigate the parameter range for which more complex signals can be obtained. Besides being simple to implement, the two-component electronic circuit setup is very cheap as compared to optical and electro-optical systems.
Directory of Open Access Journals (Sweden)
Arief Hendra Saptadi
2011-11-01
Full Text Available The application of timer/counter in microcontroller system had provided advantages in a way that it didn’t put the burden on CPU resources and enabled CPU to perform other tasks. With the availability of 8-bit and 16-bit timer/counter, the problem laid on the selection of the type of timer/counter being used. From the experiments performed, the minimum system of AVR ATmega8535 microcontroller had precisely counted a number using two different timers/counters, namely, Timer/Counter 0 (8 bit and Timer/Counter 1 (16 bit. The overflow condition achieved on 8-bit and 16-bit counting cycle activated OCR0 and OCR1AL registers, respectively. Output signals from port B.3 (OC0 and port D.5 (OC1A are then fed to oscilloscope and put into comparison. From the observation of output signals, it could be proven that the two different timers/counters had equal counting speed. Hence, it can be concluded that the selection of timers/counters is more likely based on the flexibility of count range, program size and execution time
An Improved Frame-Layer Bit Allocation Scheme for H.264/AVC Rate Control
Institute of Scientific and Technical Information of China (English)
LIN Gui-xu; ZHENG Shi-bao; ZHU Liang-jia
2009-01-01
In this paper, we aim at improving the video quality degradation due to high motions or scene changes. An improved frame-layer bit allocation scheme for H.264/AVC rate control is proposed. First, current frame is pre-encoded in 16×16 modes with a fixed quantization parameter (QP). The frame coding complexity is then measured based on the resulting bits and peak signal-to-ratio (PSNR) in the pre-coding stage. Finally, a bit budgetis calculated for current frame according to its coding complexity and inter-frame PSNR fluctuation, combined with the buffer status. Simulation results show that, in comparison with the H.264 adopted rate control scheme, our method is more efficient to suppress the sharp PSNR drops caused by high motions and scene changes. The visual quality variations in a sequence are also relieved.
Global Networks of Trade and Bits
Riccaboni, Massimo; Schiavo, Stefano
2012-01-01
Considerable efforts have been made in recent years to produce detailed topologies of the Internet. Although Internet topology data have been brought to the attention of a wide and somewhat diverse audience of scholars, so far they have been overlooked by economists. In this paper, we suggest that such data could be effectively treated as a proxy to characterize the size of the "digital economy" at country level and outsourcing: thus, we analyse the topological structure of the network of trade in digital services (trade in bits) and compare it with that of the more traditional flow of manufactured goods across countries. To perform meaningful comparisons across networks with different characteristics, we define a stochastic benchmark for the number of connections among each country-pair, based on hypergeometric distribution. Original data are thus filtered by means of different thresholds, so that we only focus on the strongest links, i.e., statistically significant links. We find that trade in bits displays...
The quantum bit from relativity of simultaneity on an interferometer
Garner, Andrew J P; Dahlsten, Oscar C O
2014-01-01
The patterns of fringes produced by an interferometer have always been important testbeds for our best contemporary theories of physics. Historically, interference has been used to contrast quantum mechanics to classical physics, but recently experiments have been performed that test quantum theory against even more exotic alternatives. A physically motivated family of theories are those where the state space of a two-level system is given by a sphere of arbitrary dimension. This includes classical bits, and real, complex and quaternionic quantum theory. In this paper, we consider relativity of simultaneity (that observers may disagree about the order of events at different locations) as applied to a two-armed interferometer. We show that this forbids most interference phenomena more complicated than those of standard complex quantum theory. In this sense, special relativity itself can be used to explain why physics should be described by the rules of quantum theory in this setup. Moreover, our result has con...
Acquisition and Retaining Granular Samples via a Rotating Coring Bit
Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart
2013-01-01
This device takes advantage of the centrifugal forces that are generated when a coring bit is rotated, and a granular sample is entered into the bit while it is spinning, making it adhere to the internal wall of the bit, where it compacts itself into the wall of the bit. The bit can be specially designed to increase the effectiveness of regolith capturing while turning and penetrating the subsurface. The bit teeth can be oriented such that they direct the regolith toward the bit axis during the rotation of the bit. The bit can be designed with an internal flute that directs the regolith upward inside the bit. The use of both the teeth and flute can be implemented in the same bit. The bit can also be designed with an internal spiral into which the various particles wedge. In another implementation, the bit can be designed to collect regolith primarily from a specific depth. For that implementation, the bit can be designed such that when turning one way, the teeth guide the regolith outward of the bit and when turning in the opposite direction, the teeth will guide the regolith inward into the bit internal section. This mechanism can be implemented with or without an internal flute. The device is based on the use of a spinning coring bit (hollow interior) as a means of retaining granular sample, and the acquisition is done by inserting the bit into the subsurface of a regolith, soil, or powder. To demonstrate the concept, a commercial drill and a coring bit were used. The bit was turned and inserted into the soil that was contained in a bucket. While spinning the bit (at speeds of 600 to 700 RPM), the drill was lifted and the soil was retained inside the bit. To prove this point, the drill was turned horizontally, and the acquired soil was still inside the bit. The basic theory behind the process of retaining unconsolidated mass that can be acquired by the centrifugal forces of the bit is determined by noting that in order to stay inside the interior of the bit, the
Jianghan PDC Bits Open Good Market in Singapore
Institute of Scientific and Technical Information of China (English)
Wang Tongliang
1995-01-01
@@ The PDC bits produced by PDC Division,Jianghan Drill Bit Plant won good reputation,because of its good quality and appearance in 94 South-east Asia Offshore Petroleum Engineering Product Exhibition held by Singapore International Exhibition Center.
Rate distortion optimal bit allocation methods for volumetric data using JPEG 2000.
Kosheleva, Olga M; Usevitch, Bryan E; Cabrera, Sergio D; Vidal, Edward
2006-08-01
Computer modeling programs that generate three-dimensional (3-D) data on fine grids are capable of generating very large amounts of information. These data sets, as well as 3-D sensor/measured data sets, are prime candidates for the application of data compression algorithms. A very flexible and powerful compression algorithm for imagery data is the newly released JPEG 2000 standard. JPEG 2000 also has the capability to compress volumetric data, as described in Part 2 of the standard, by treating the 3-D data as separate slices. As a decoder standard, JPEG 2000 does not describe any specific method to allocate bits among the separate slices. This paper proposes two new bit allocation algorithms for accomplishing this task. The first procedure is rate distortion optimal (for mean squared error), and is conceptually similar to postcompression rate distortion optimization used for coding codeblocks within JPEG 2000. The disadvantage of this approach is its high computational complexity. The second bit allocation algorithm, here called the mixed model (MM) approach, mathematically models each slice's rate distortion curve using two distinct regions to get more accurate modeling at low bit rates. These two bit allocation algorithms are applied to a 3-D Meteorological data set. Test results show that the MM approach gives distortion results that are nearly identical to the optimal approach, while significantly reducing computational complexity.
2-bit Flip Mutation Elementary Fitness Landscapes
Langdon, William
2010-01-01
Genetic Programming parity is not elementary. GP parity cannot be represented as the sum of a small number of elementary landscapes. Statistics, including fitness distance correlation, of Parity's fitness landscape are calculated. Using Walsh analysis the eigen values and eigenvectors of the Laplacian of the two bit flip fitness landscape are given and a ruggedness measure for elementary landscapes is proposed. An elementary needle in a haystack (NIH) landscape is g...
Blind One-Bit Compressive Sampling
2013-01-17
notation and recalling some background from convex analysis . For the d-dimensional Euclidean space Rd, the class of all lower semicontinuous convex...compressed sensing, Applied and Computational Harmonic Analysis , 27 (2009), pp. 265 – 274. [3] P. T. Boufounos and R. G. Baraniuk, 1-bit compressive sensing...Convergence analysis of the algorithm is presented. Our approach is to obtain a sequence of optimization problems by successively approximating the ℓ0
NSC 800, 8-bit CMOS microprocessor
Suszko, S. F.
1984-01-01
The NSC 800 is an 8-bit CMOS microprocessor manufactured by National Semiconductor Corp., Santa Clara, California. The 8-bit microprocessor chip with 40-pad pin-terminals has eight address buffers (A8-A15), eight data address -- I/O buffers (AD(sub 0)-AD(sub 7)), six interrupt controls and sixteen timing controls with a chip clock generator and an 8-bit dynamic RAM refresh circuit. The 22 internal registers have the capability of addressing 64K bytes of memory and 256 I/O devices. The chip is fabricated on N-type (100) silicon using self-aligned polysilicon gates and local oxidation process technology. The chip interconnect consists of four levels: Aluminum, Polysi 2, Polysi 1, and P(+) and N(+) diffusions. The four levels, except for contact interface, are isolated by interlevel oxide. The chip is packaged in a 40-pin dual-in-line (DIP), side brazed, hermetically sealed, ceramic package with a metal lid. The operating voltage for the device is 5 V. It is available in three operating temperature ranges: 0 to +70 C, -40 to +85 C, and -55 to +125 C. Two devices were submitted for product evaluation by F. Stott, MTS, JPL Microprocessor Specialist. The devices were pencil-marked and photographed for identification.
1/N Perturbations in Superstring Bit Models
Thorn, Charles B
2015-01-01
We develop the 1/N expansion for stable string bit models, focusing on a model with bit creation operators carrying only transverse spinor indices a=1,...,s. At leading order (1/N=0), this model produces a (discretized) lightcone string with a "transverse space' of $s$ Grassmann worldsheet fields. Higher orders in the 1/N expansion are shown to be determined by the overlap of a single large closed chain (discretized string) with two smaller closed chains. In the models studied here, the overlap is not accompanied with operator insertions at the break/join point. Then the requirement that the discretized overlap have a smooth continuum limit leads to the critical Grassmann "dimension" of s=24. This "protostring", a Grassmann analog of the bosonic string, is unusual, because it has no large transverse dimensions. It is a string moving in one space dimension and there are neither tachyons nor massless particles. The protostring, derived from our pure spinor string bit model, has 24 Grassmann dimensions, 16 of wh...
Verilog Implementation of 32-Bit CISC Processor
Directory of Open Access Journals (Sweden)
P.Kanaka Sirisha
2016-04-01
Full Text Available The Project deals with the design of the 32-Bit CISC Processor and modeling of its components using Verilog language. The Entire Processor uses 32-Bit bus to deal with all the registers and the memories. This Processor implements various arithmetic, logical, Data Transfer operations etc., using variable length instructions, which is the core property of the CISC Architecture. The Processor also supports various addressing modes to perform a 32-Bit instruction. Our Processor uses Harvard Architecture (i.e., to have a separate program and data memory and hence has different buses to negotiate with the Program Memory and Data Memory individually. This feature enhances the speed of our processor. Hence it has two different Program Counters to point to the memory locations of the Program Memory and Data Memory.Our processor has ‘Instruction Queuing’ which enables it to save the time needed to fetch the instruction and hence increases the speed of operation. ‘Interrupt Service Routine’ is provided in our Processor to make it address the Interrupts.
Optimal One Bit Time Reversal For UWB Impulse Radio In Multi-User Wireless Communications
DEFF Research Database (Denmark)
Nguyen, Hung Tuan
2008-01-01
In this paper, with the purpose of further reducing the complexity of the system, while keeping its temporal and spatial focusing performance, we investigate the possibility of using optimal one bit time reversal (TR) system for impulse radio ultra wideband multi-user wireless communications...
Huang, Jiaxin; Zhang, Xiaorong; Yao, Ji
2014-04-01
To construct a 3D finite-element model of the craniofacial complex with the original DICOM data of CT and to investigate the preliminary biomechanical characteristics with different directions and magnitudes of retractive forces to the maxilla of rhesus monkeys. A male rhesus monkey with mixed dentition was used. Spiral CT was performed to establish a 3D finite-element model of the craniofacial complex. The ANSYS 12.1 software was used to analyze craniofacial complex displacement. Each landmark showed larger displacement with increasing force value. The displacement values and force size exhibited a linear relationship. In the x-axis direction, all displacements were small. In the y-axis direction, all displacements showed significantly higher changes with increasing force value displacement. In the z-axis direction, the A-point and ANS point moved downward, but PNS moved upward. Loading retractive force resultes in an apparent backward and clockwise rotation on the maxilla with no obvious effects on the width of the upper jaw.
Reversible n-Bit to n-Bit Integer Haar-Like Transforms
Energy Technology Data Exchange (ETDEWEB)
Senecal, J; Duchaineau, M; Joy, K I
2003-11-03
We introduce a wavelet-like transform similar to the Haar transform, but with the properties that it packs the results into the same number of bits as the original data, and is reversible. Our method, called TLHaar, uses table lookups to replace the averaging, differencing, and bit shifting performed in a Haar IntegerWavelet Transform (IWT). TLHaar maintains the same coefficient magnitude relationships for the low- and high-pass coefficients as true Haar, but reorders them to fit into the same number of bits as the input signal, thus eliminating the sign bit that is added to the Haar IWT output coefficients. Eliminating the sign bit avoids using extra memory and speeds the transform process. We tested TLHaar on a variety of image types, and when compared to the Haar IWT TLHaar is significantly faster. For image data with lines or hard edges TLHaar coefficients compress better than those of the Haar IWT. Due to its speed TLHaar is suitable for streaming hardware implementations with fixed data sizes, such as DVI channels.
A CMOS Imager with Focal Plane Compression using Predictive Coding
Leon-Salas, Walter D.; Balkir, Sina; Sayood, Khalid; Schemm, Nathan; Hoffman, Michael W.
2007-01-01
This paper presents a CMOS image sensor with focal-plane compression. The design has a column-level architecture and it is based on predictive coding techniques for image decorrelation. The prediction operations are performed in the analog domain to avoid quantization noise and to decrease the area complexity of the circuit, The prediction residuals are quantized and encoded by a joint quantizer/coder circuit. To save area resources, the joint quantizerlcoder circuit exploits common circuitry between a single-slope analog-to-digital converter (ADC) and a Golomb-Rice entropy coder. This combination of ADC and encoder allows the integration of the entropy coder at the column level. A prototype chip was fabricated in a 0.35 pm CMOS process. The output of the chip is a compressed bit stream. The test chip occupies a silicon area of 2.60 mm x 5.96 mm which includes an 80 X 44 APS array. Tests of the fabricated chip demonstrate the validity of the design.
A novel bit-quad-based Euler number computing algorithm.
Yao, Bin; He, Lifeng; Kang, Shiying; Chao, Yuyan; Zhao, Xiao
2015-01-01
The Euler number of a binary image is an important topological property in computer vision and pattern recognition. This paper proposes a novel bit-quad-based Euler number computing algorithm. Based on graph theory and analysis on bit-quad patterns, our algorithm only needs to count two bit-quad patterns. Moreover, by use of the information obtained during processing the previous bit-quad, the average number of pixels to be checked for processing a bit-quad is only 1.75. Experimental results demonstrated that our method outperforms significantly conventional Euler number computing algorithms.
A novel bit-quad-based Euler number computing algorithm
Yao, Bin; He, Lifeng; Kang, Shiying; Chao, Yuyan; Xiao ZHAO
2015-01-01
The Euler number of a binary image is an important topological property in computer vision and pattern recognition. This paper proposes a novel bit-quad-based Euler number computing algorithm. Based on graph theory and analysis on bit-quad patterns, our algorithm only needs to count two bit-quad patterns. Moreover, by use of the information obtained during processing the previous bit-quad, the average number of pixels to be checked for processing a bit-quad is only 1.75. Experimental results ...
Adaptive Power and Bit Allocation in Multicarrier Systems
Institute of Scientific and Technical Information of China (English)
HUO Yong-qing; PENG Qi-cong; SHAO Huai-zong
2007-01-01
We present two adaptive power and bit allocation algorithms for multicarrier systems in a frequency selective fading environment. One algorithm allocates bit based on maximizing the channel capacity, another allocates bit based on minimizing the bit-error-rate(BER). Two algorithms allocate power based on minimizing the BER. Results show that the proposed algorithms are more effective than Fischer's algorithm at low average signal-to-noise ration (SNR). This indicates that our algorithms can achieve high spectral efficiency and high communication reliability during bad channel state. Results also denote the bit and power allocation of each algorithm and effects of the number of subcarriers on the BER performance.
Compact high-performance MWIR camera with exposure control and 12-bit video processor
Villani, Thomas S.; Loesser, Kenneth A.; Perna, Steve N.; McCarthy, D. R.; Pantuso, Francis P.
1998-07-01
The design and performance of a compact infrared camera system is presented. The 3 - 5 micron MWIR imaging system consists of a Stirling-cooled 640 X 480 staring PtSi infrared focal plane array (IRFPA) with a compact, high-performance 12-bit digital image processor. The low-noise CMOS IRFPA is X-Y addressable, utilizes on-chip-scanning registers and has electronic exposure control. The digital image processor uses 16-frame averaged, 2-point non-uniformity compensation and defective pixel substitution circuitry. There are separate 12- bit digital and analog I/O ports for display control and video output. The versatile camera system can be configured in NTSC, CCIR, and progressive scan readout formats and the exposure control settings are digitally programmable.
Barwick, Susan
2008-01-01
Unitals are key structures in projective planes, and have connections with other structures in algebra. This book presents a monograph on unitals embedded in finite projective planes. It offers a survey of the research literature on embedded unitals. It is suitable for graduate students and researchers who want to learn about this topic
A one-bit approach for image registration
Nguyen, An Hung; Pickering, Mark; Lambert, Andrew
2015-02-01
Motion estimation or optic flow computation for automatic navigation and obstacle avoidance programs running on Unmanned Aerial Vehicles (UAVs) is a challenging task. These challenges come from the requirements of real-time processing speed and small light-weight image processing hardware with very limited resources (especially memory space) embedded on the UAVs. Solutions towards both simplifying computation and saving hardware resources have recently received much interest. This paper presents an approach for image registration using binary images which addresses these two requirements. This approach uses translational information between two corresponding patches of binary images to estimate global motion. These low bit-resolution images require a very small amount of memory space to store them and allow simple logic operations such as XOR and AND to be used instead of more complex computations such as subtractions and multiplications.
Where the "it from bit" come from?
Foschini, Luigi
2013-01-01
In his 1989 essay, John Archibald Wheeler has tried to answer the eternal question of existence. He did it by searching for links between information, physics, and quanta. The main concept emerging from his essay is that "every physical quantity, every it, derives its ultimate significance from bits, binary yes-or-no indications". This concept has been summarized in the catchphrase "it from bit". In the Wheeler's essay, it is possible to read several times the echoes of the philosophy of Niels Bohr. The Danish physicist has pointed out how the quantum and relativistic physics - forcing us to abandon the anchor of the visual reference of common sense - have imposed a greater attention to the language. Bohr did not deny the physical reality, but recognizes that there is always need of a language no matter what a person wants to do. To put it as Carlo Sini, language is the first toolbox that man has at hands to analyze the experience. It is not a thought translated into words, because to think is to operate with...
Simplified Metrics Calculation for Soft Bit Detection in DVB-T2
Directory of Open Access Journals (Sweden)
D. Perez-Calderon
2014-04-01
Full Text Available The constellation rotation and cyclic quadrature component delay (RQD technique has been adopted in the second generation terrestrial digital video broadcasting (DVB-T2 standard. It improves the system performance under severe propagation conditions, but introduces serious complexity problems in the hardware implementation of the detection process. In this paper, we present a simplified scheme that greatly reduces the complexity of the demapper by simplifying the soft bit metrics computation having a negligible overall system performance loss.
unknown
1991-01-01
Abstract of NL 8902368 (A) The system converts a PCM input signal. It has a series of digital words, each K bits long at a predetermined repetition frequency converted into a PCM output signal (16) comprising a series of digital words each L bits long, where L is less than K. The system includes a
Wavelets as q-bits and q-bit states as wavelets
Steblinski, Pawel; Blachowicz, Tomasz
2009-01-01
In this short report it is argued that by the use of wavelets formalism it is possible to describe the q-bit state. The wavelet formalism address the real-valued physical signals, for example, obtained during typical physical measurements.
Energy Technology Data Exchange (ETDEWEB)
Fukushima, Akio, E-mail: akio.fukushima@aist.go.jp; Yakushiji, Kay; Konoto, Makoto; Kubota, Hitoshi; Imamura, Hiroshi; Yuasa, Shinji
2016-02-15
We newly developed a magnetic memory cell having multi-bit function. The memory cell composed of a perpendicularly magnetized magnetic tunnel junction (MB-pMTJ) and a synthetic antiferromagnetic reference layer. The multi-bit function is realized by combining the freedom of states of the magnetic free layer and that in the antiferromagnetically coupled reference layer. The structure of the reference layer is (FeB/Ta/[Co/Pt]{sub 3})/Ru/([Co/Pt]{sub 6}); the top and the bottom layers are coupled through Ru layer where the reference layer has two degrees of freedom of a head-to-head and a bottom-to-bottom magnetic configuration. A four-state memory cell is realized by combination of both degrees of freedom. The states in the reference layer however is hardly detected by the total resistance of MB-pMTJ, because the magnetoresistance effect in the reference layer is negligibly small. That implies that the resistance values for the different states in the reference layer are degenerated. On the other hand, the two different states in the reference layer bring different stray fields to the free layer, which generate two different minor loop with different switching fields. Therefore, the magnetic states in the reference layer can be differentiated by the two-step reading, before and after applying the appropriately pulsed magnetic field which can identify the initial state in the reference layer. This method is similar to distinguishing different magnetic states in an in-plane magnetized spin-valve element. We demonstrated that four different states in the MB-pMTJ can be distinguished by the two-step read-out. The important feature of the two-step reading is a practically large operation margins (large resistance change in reading) which is equal to that of a single MTJ. Even though the two-step reading is a destructive method by which 50% of the magnetic state is changed, this MB-pMTJ is promising for high density non-volatile memory cell with a minor cost of operation
Temperature-compensated 8-bit column driver for AMLCD
Dingwall, Andrew G. F.; Lin, Mark L.
1995-06-01
An all-digital, 5 V input, 50 Mhz bandwidth, 10-bit resolution, 128- column, AMLCD column driver IC has been designed and tested. The 10-bit design can enhance display definition over 6-bit nd 8-bit column drivers. Precision is realized with on-chip, switched-capacitor DACs plus transparently auto-offset-calibrated, opamp outputs. Increased resolution permits multiple 10-bit digital gamma remappings in EPROMs over temperature. Driver IC features include externally programmable number of output column, bi-directional digital data shifting, user- defined row/column/pixel/frame inversion, power management, timing control for daisy-chained column drivers, and digital bit inversion. The architecture uses fewer reference power supplies.
Cross Institutional Cooperation on a Shared Bit Repository
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad
2013-01-01
This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation, in order to use their resources for preservation in a more cost-effective way. It uses the OAIS Reference Model to provide a framework...... for systematically analysing institutions technical and organisational requirements for a remote bit repository. Instead of viewing a bit repository simply as Archival Storage for the institutions repositories, we argue for viewing it as consisting of a subset of functions from all entities defined by the OAIS...... Reference Model. The work is motivated by and used in a current Danish feasibility study for establishing a national bit repository. The study revealed that depending on their missions and the collections they hold, the institutions have varying requirements e.g. for bit safety, accessibility...
Cross Institutional Cooperation on a Shared Bit Repository
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad
2010-01-01
for systematically analysing the technical and organizational requirements of institutions for a remote bit repository. Instead of viewing a bit repository simply as Archival Storage for the institutions’ repositories, we argue for viewing it as consisting of a subset of functions from all entities defined...... architecture and its strengths in being flexible in order to offer differentiated services with respect to, among other things, bit safety and cost. Furthermore, the challenges in formulating various aspects, such as risk requirements, are described....
Development and testing of a Mudjet-augmented PDC bit.
Energy Technology Data Exchange (ETDEWEB)
Black, Alan (TerraTek, Inc.); Chahine, Georges (DynaFlow, Inc.); Raymond, David Wayne; Matthews, Oliver (Security DBS); Grossman, James W.; Bertagnolli, Ken (US Synthetic); Vail, Michael (US Synthetic)
2006-01-01
This report describes a project to develop technology to integrate passively pulsating, cavitating nozzles within Polycrystalline Diamond Compact (PDC) bits for use with conventional rig pressures to improve the rock-cutting process in geothermal formations. The hydraulic horsepower on a conventional drill rig is significantly greater than that delivered to the rock through bit rotation. This project seeks to leverage this hydraulic resource to extend PDC bits to geothermal drilling.
Gravitational Entropy and String Bits on the Stretched Horizon
Halyo, E
2003-01-01
We show that the entropy of Schwarzschild black holes in any dimension can be described by a gas of free string bits at the stretched horizon. The number of string bits is equal to the black hole entropy and energy dependent. For an asymptotic observer the bit gas is at the Hawking temperature. We show that the same description is also valid for de Sitter space--times in any dimension.
Bit Patterned Magnetic Recording: Theory, Media Fabrication, and Recording Performance
Albrecht, Thomas R.; Arora, Hitesh; Ayanoor-Vitikkate, Vipin; Beaujour, Jean-Marc; Bedau, Daniel; Berman, David; Bogdanov, Alexei L.; Chapuis, Yves-Andre; Cushen, Julia; Dobisz, Elizabeth E.; Doerk, Gregory; Gao, He; Grobis, Michael; Gurney, Bruce; Hanson, Weldon
2015-01-01
Bit Patterned Media (BPM) for magnetic recording provide a route to densities $>1 Tb/in^2$ and circumvents many of the challenges associated with conventional granular media technology. Instead of recording a bit on an ensemble of random grains, BPM uses an array of lithographically defined isolated magnetic islands, each of which stores one bit. Fabrication of BPM is viewed as the greatest challenge for its commercialization. In this article we describe a BPM fabrication method which combine...
Directory of Open Access Journals (Sweden)
VINOTH BABU K.
2016-04-01
Full Text Available Multi input multi output (MIMO and orthogonal frequency division multiplexing (OFDM are the key techniques for the future wireless communication systems. Previous research in the above areas mainly concentrated on spectral efficiency improvement and very limited work has been done in terms of energy efficient transmission. In addition to spectral efficiency improvement, energy efficiency improvement has become an important research because of the slow progressing nature of the battery technology. Since most of the user equipments (UE rely on battery, the energy required to transmit the target bits should be minimized to avoid quick battery drain. The frequency selective fading nature of the wireless channel reduces the spectral and energy efficiency of OFDM based systems. Dynamic bit loading (DBL is one of the suitable solution to improve the spectral and energy efficiency of OFDM system in frequency selective fading environment. Simple dynamic bit loading (SDBL algorithm is identified to offer better energy efficiency with less system complexity. It is well suited for fixed data rate voice/video applications. When the number of target bits are very much larger than the available subcarriers, the conventional single input single output (SISO-SDBL scheme offers high bit error rate (BER and needs large transmit energy. To improve bit error performance we combine space frequency block codes (SFBC with SDBL, where the adaptations are done in both frequency and spatial domain. To improve the quality of service (QoS further, optimal transmit antenna selection (OTAS scheme is also combined with SFBC-SDBL scheme. The simulation results prove that the proposed schemes offer better QoS when compared to the conventional SISOSDBL scheme.
Zeh, H D
2002-01-01
Schroedinger's wave function shows many aspects of a state of incomplete knowledge or information ("bit"): (1) it is defined on a space of classical configurations, (2) its generic entanglement is, therefore, analogous to statistical correlations, and (3) it determines probabilites of measurement outcomes. Nonetheless, quantum superpositions (such as represented by a wave function) also define individual physical states ("it"). This conceptual dilemma may have its origin in the conventional operational foundation of physical concepts, successful in classical physics, but inappropriate in quantum theory because of the existence of mutually exclusive operations (used for the definition of concepts). In contrast, a hypothetical realism, based on concepts that are justified only by their universal and consistent applicability, favors the wave function as a description of (thus nonlocal) physical reality. The (conceptually local) classical world then appears as an illusion, facilitated by the phenomenon of decoher...
Bit-Optimal Lempel-Ziv compression
Ferragina, Paolo; Venturini, Rossano
2008-01-01
One of the most famous and investigated lossless data-compression scheme is the one introduced by Lempel and Ziv about 40 years ago. This compression scheme is known as "dictionary-based compression" and consists of squeezing an input string by replacing some of its substrings with (shorter) codewords which are actually pointers to a dictionary of phrases built as the string is processed. Surprisingly enough, although many fundamental results are nowadays known about upper bounds on the speed and effectiveness of this compression process and references therein), ``we are not aware of any parsing scheme that achieves optimality when the LZ77-dictionary is in use under any constraint on the codewords other than being of equal length'' [N. Rajpoot and C. Sahinalp. Handbook of Lossless Data Compression, chapter Dictionary-based data compression. Academic Press, 2002. pag. 159]. Here optimality means to achieve the minimum number of bits in compressing each individual input string, without any assumption on its ge...
The implementation of bit-parallelism for DNA sequence alignment
Setyorini; Kuspriyanto; Widyantoro, D. H.; Pancoro, A.
2017-05-01
Dynamic Programming (DP) remain the central algorithm of biological sequence alignment. Matching score computation is the most time-consuming process. Bit-parallelism is one of approximate string matching techniques that transform DP matrix cell unit processing into word unit (groups of cell). Bit-parallelism computate the scores column-wise. Adopting from word processing in computer system work, this technique promise reducing time in score computing process in DP matrix. In this paper, we implement bit-parallelism technique for DNA sequence alignment. Our bit-parallelism implementation have less time for score computational process but still need improvement for there construction process.
PDC (polycrystalline diamond compact) bit research at Sandia National Laboratories
Energy Technology Data Exchange (ETDEWEB)
Finger, J.T.; Glowka, D.A.
1989-06-01
From the beginning of the geothermal development program, Sandia has performed and supported research into polycrystalline diamond compact (PDC) bits. These bits are attractive because they are intrinsically efficient in their cutting action (shearing, rather than crushing) and they have no moving parts (eliminating the problems of high-temperature lubricants, bearings, and seals.) This report is a summary description of the analytical and experimental work done by Sandia and our contractors. It describes analysis and laboratory tests of individual cutters and complete bits, as well as full-scale field tests of prototype and commercial bits. The report includes a bibliography of documents giving more detailed information on these topics. 26 refs.
Barkin, Yu. V.; Ferrandiz, J. M.
2009-04-01
Introduction. In 1988 I. Kholin [1] has developed a precision method of determination of parameters of rotation of planets on complex radar-tracking observations on two radio telescopes making base and definitely carried on surface of the Earth. His American colleagues for the period approximately in 4 with small year have executed a series of radar-tracking measurements on a method and I. Kholin's program [2] and have obtained for the specified period 21 values of angular velocity of rotation of this planet [3]. With the help of numerical integration of the equations of rotary motion on the found values they managed to determine with high accuracy the basic dynamic parameter in the theory of Mercury librations (B - A)Cm = (2.03± 0.12) × 10-4 and the corresponding to it the value of amplitude of the basic librations35"8 ± 2"1. These results have served as convincing arguments for the benefit of the Peale's assumption, that a core of Mercury is liquid, or in partially molten [4]. Authors also managed to obtain for the first time parameters of resonant librations in a longitude which opening from radar observations was predicted earlier [5]. Its amplitude makes about 300", the period is equal approximately to 12 years. In the paper [6] parameters of the perturbed rotational motion have been determined with the help of the analytical theory and with formal using of results of mentioned work [3] on determination of 21 values of angular velocity of Mercury. In result the estimations of amplitudes of forced librations of first five harmonics with the periods: 87.97 d, 43.99 d, 29.33 d, 21.99 d and 17.59 d have been obtained. The appropriate amplitudes make values:34"05 ± 1"27, 3"59 ± 0"13, 0"354 ± 0"013, 0"072 ± 0"003 and 0"016 ± 0"001. The amplitude and the period of free librations of Mercury in a longitude are determined: 290"9 ± 67"0 and 12.37 ± 0.23 yr, consequently. The phase of this variation has made28401 ± 1402. In the paper we construct the similar
BitPredator: A Discovery Algorithm for BitTorrent Initial Seeders and Peers
Energy Technology Data Exchange (ETDEWEB)
Borges, Raymond [West Virginia University; Patton, Robert M [ORNL; Kettani, Houssain [Polytechnic University of Puerto Rico (PUPR); Masalmah, Yahya [Universidad del Turabo
2011-01-01
There is a large amount of illegal content being replicated through peer-to-peer (P2P) networks where BitTorrent is dominant; therefore, a framework to profile and police it is needed. The goal of this work is to explore the behavior of initial seeds and highly active peers to develop techniques to correctly identify them. We intend to establish a new methodology and software framework for profiling BitTorrent peers. This involves three steps: crawling torrent indexers for keywords in recently added torrents using Really Simple Syndication protocol (RSS), querying torrent trackers for peer list data and verifying Internet Protocol (IP) addresses from peer lists. We verify IPs using active monitoring methods. Peer behavior is evaluated and modeled using bitfield message responses. We also design a tool to profile worldwide file distribution by mapping IP-to-geolocation and linking to WHOIS server information in Google Earth.
Directory of Open Access Journals (Sweden)
K. K. L. B. Adikaram
2014-01-01
Full Text Available With the increasing demand for online/inline data processing efficient Fourier analysis becomes more and more relevant. Due to the fact that the bit reversal process requires considerable processing time of the Fast Fourier Transform (FFT algorithm, it is vital to optimize the bit reversal algorithm (BRA. This paper is to introduce an efficient BRA with multiple memory structures. In 2009, Elster showed the relation between the first and the second halves of the bit reversal permutation (BRP and stated that it may cause serious impact on cache performance of the computer, if implemented. We found exceptions, especially when the said index mapping was implemented with multiple one-dimensional memory structures instead of multidimensional or one-dimensional memory structure. Also we found a new index mapping, even after the recursive splitting of BRP into equal sized slots. The four-array and the four-vector versions of BRA with new index mapping reported 34% and 16% improvement in performance in relation to similar versions of Linear BRA of Elster which uses single one-dimensional memory structure.
Holomorphic dynamical systems in the complex plane
DEFF Research Database (Denmark)
Branner, Bodil
1997-01-01
The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarities between Julia sets of certain quadratic polynomials and the Madelbrot...
Holomorphic Dynamical Systems in the Complex Plane
DEFF Research Database (Denmark)
Branner, Bodil
1996-01-01
The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarity between Juliasets of certain quadratic polynomials and the Mandelbrot set....
Holomorphic dynamical systems in the complex plane
DEFF Research Database (Denmark)
Branner, Bodil
1997-01-01
The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarities between Julia sets of certain quadratic polynomials and the Madelbrot...
Holomorphic Dynamical Systems in the Complex Plane
DEFF Research Database (Denmark)
Branner, Bodil
1996-01-01
The paper reviews some basic properties of Julia sets of polynomials and the Mandelbrot set. In particular we emphasize the concept of normal families, the importance of repelling periodic points and the asymptotic similarity between Juliasets of certain quadratic polynomials and the Mandelbrot set....
Energy Technology Data Exchange (ETDEWEB)
Lampton, Michael L.; Kim, A.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Berkovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro,R.; Ealet, A.; Ellis, R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland, S.E.; Huterer, D.; Karcher, A.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder,E.V.; Loken, S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto, E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.
2002-07-29
The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square-degree field sensitive in the visible and near-infrared wavelength regime. We describe the requirements for the instrument suite and the evolution of the focal plane design to the present concept in which all the instrumentation--visible and near-infrared imagers, spectrograph, and star guiders--share one common focal plane.
Translation planes foundations and construction principles
Knarr, Norbert
1995-01-01
The book discusses various construction principles for translation planes and spreads from a general and unifying point of view and relates them to the theory of kinematic spaces. The book is intended for people working in the field of incidence geometry and can be read by everyone who knows the basic facts about projective and affine planes. The methods developed work especially well for topological spreads of real and complex vector spaces. In particular, a complete classification of all semifield spreads of finite dimensional complex vector spaces is obtained.
Circuit and interconnect design for high bit-rate applications
Veenstra, H.
2006-01-01
This thesis presents circuit and interconnect design techniques and design flows that address the most difficult and ill-defined aspects of the design of ICs for high bit-rate applications. Bottlenecks in interconnect design, circuit design and on-chip signal distribution for high bit-rate applicati
Cryptographic Properties of the Hidden Weighted Bit Function
2013-12-23
Pohlig–Hellman method, the 20-variable Carlet–Feng function allows computing one output bit per cycle with more than 1000 half- adders and full- adders . In...comparison, the 64-variable HWBF allows computing one output bit with only 26 − 1 = 63 half- adders and 26 − 6− 1 = 57 full- adders [16]. Therefore, by
Parallel SAT Solving using Bit-level Operations
Heule, M.J.H.; Van Maaren, H.
2008-01-01
We show how to exploit the 32/64 bit architecture of modern computers to accelerate some of the algorithms used in satisfiability solving by modifying assignments to variables in parallel on a single processor. Techniques such as random sampling demonstrate that while using bit vectors instead of Bo
Gradient Descent Bit Flipping Algorithms for Decoding LDPC Codes
Wadayama, Tadashi; Nakamura, Keisuke; Yagita, Masayuki; Funahashi, Yuuki; Usami, Shogo; Takumi, Ichi
2007-01-01
A novel class of bit-flipping (BF) algorithms for decoding low-density parity-check (LDPC) codes is presented. The proposed algorithms, which are called gradient descent bit flipping (GDBF) algorithms, can be regarded as simplified gradient descent algorithms. Based on gradient descent formulation, the proposed algorithms are naturally derived from a simple non-linear objective function.
16 Bits DAC s Design, Simulation and Layout
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The high speed and precision 16 bits DAC will be applied in DSP (Digital Signal Processing) based on CSR pulsed power supply control system. In this application the DAC is needed to work in 1 μs’ converting data rate, 16 bit resolution and its output voltage is 10 volts.
Kim, Min-Kyu; Hong, Seong-Kwan; Kwon, Oh-Kyong
2015-12-26
This paper presents a fast multiple sampling method for low-noise CMOS image sensor (CIS) applications with column-parallel successive approximation register analog-to-digital converters (SAR ADCs). The 12-bit SAR ADC using the proposed multiple sampling method decreases the A/D conversion time by repeatedly converting a pixel output to 4-bit after the first 12-bit A/D conversion, reducing noise of the CIS by one over the square root of the number of samplings. The area of the 12-bit SAR ADC is reduced by using a 10-bit capacitor digital-to-analog converter (DAC) with four scaled reference voltages. In addition, a simple up/down counter-based digital processing logic is proposed to perform complex calculations for multiple sampling and digital correlated double sampling. To verify the proposed multiple sampling method, a 256 × 128 pixel array CIS with 12-bit SAR ADCs was fabricated using 0.18 μm CMOS process. The measurement results shows that the proposed multiple sampling method reduces each A/D conversion time from 1.2 μs to 0.45 μs and random noise from 848.3 μV to 270.4 μV, achieving a dynamic range of 68.1 dB and an SNR of 39.2 dB.
Numerical optimization of writer and media for bit patterned magnetic recording
Kovacs, A.; Oezelt, H.; Schabes, M. E.; Schrefl, T.
2016-07-01
In this work, we present a micromagnetic study of the performance potential of bit-patterned (BP) magnetic recording media via joint optimization of the design of the media and of the magnetic write heads. Because the design space is large and complex, we developed a novel computational framework suitable for parallel implementation on compute clusters. Our technique combines advanced global optimization algorithms and finite-element micromagnetic solvers. Targeting data bit densities of 4 Tb/in2, we optimize designs for centered, staggered, and shingled BP writing. The magnetization dynamics of the switching of the exchange-coupled composite BP islands of the media is treated micromagnetically. Our simulation framework takes into account not only the dynamics of on-track errors but also the thermally induced adjacent-track erasure. With co-optimized write heads, the results show superior performance of shingled BP magnetic recording where we identify two particular designs achieving write bit-error rates of 1.5 ×10-8 and 8.4 ×10-8 , respectively. A detailed description of the key design features of these designs is provided and contrasted with centered and staggered BP designs which yielded write bit error rates of only 2.8 ×10-3 (centered design) and 1.7 ×10-2 (staggered design) even under optimized conditions.
IMAGE STEGANOGRAPHY DENGAN METODE LEAST SIGNIFICANT BIT (LSB
Directory of Open Access Journals (Sweden)
M. Miftakul Amin
2014-02-01
Full Text Available Security in delivering a secret message is an important factor in the spread of information in cyberspace. Protecting that message to be delivered to the party entitled to, should be made a message concealment mechanism. The purpose of this study was to hide a secret text message into digital images in true color 24 bit RGB format. The method used to insert a secret message using the LSB (Least Significant Bit by replacing the last bit or 8th bit in each RGB color component. RGB image file types option considering that messages can be inserted capacity greater than if use a grayscale image, this is because in one pixel can be inserted 3 bits message. Tests provide results that are hidden messages into a digital image does not reduce significantly the quality of the digital image, and the message has been hidden can be extracted again, so that messages can be delivered to the recipient safely.
Cross Institutional Cooperation on a Shared Bit Repository
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad
2010-01-01
This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation in order to use their resources for preservation n in a more cost-effective way. It uses the OAIS Reference Model to provide a framework......, and confidentiality. This study further revealed that requirements for the level of bit safety must be supplemented by risk analysis, which needs to involve elements of the architecture; for example, the number of copies and how independence between the copies is ensured. The paper describes bit repository...... architecture and its strengths in being flexible in order to offer differentiated services with respect to, among other things, bit safety and cost. Furthermore, the challenges in formulating various aspects, such as risk requirements, are described....
Cross Institutional Cooperation on a Shared Bit Repository
DEFF Research Database (Denmark)
Zierau, Eld; Kejser, Ulla Bøgvad
2013-01-01
This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation, in order to use their resources for preservation in a more cost-effective way. It uses the OAIS Reference Model to provide a framework......, and confidentiality. This study furthermore revealed that requirements for the level of bit safety must be supplemented by risk analysis, which needs to involve elements of the architecture, e.g. the number of copies and how independence between the copies is ensured. The paper describes the bit repository...... architecture, its strengths in being flexible in order to offer differentiated services with respect to, among other things, bit safety and cost. Furthermore, the challenges in formulating e.g. risk requirements are described....
Uniqueness: skews bit occurrence frequencies in randomly generated fingerprint libraries.
Chen, Nelson G
2016-08-01
Requiring that randomly generated chemical fingerprint libraries have unique fingerprints such that no two fingerprints are identical causes a systematic skew in bit occurrence frequencies, the proportion at which specified bits are set. Observed frequencies (O) at which each bit is set within the resulting libraries systematically differ from frequencies at which bits are set at fingerprint generation (E). Observed frequencies systematically skew toward 0.5, with the effect being more pronounced as library size approaches the compound space, which is the total number of unique possible fingerprints given the number of bit positions each fingerprint contains. The effect is quantified for varying library sizes as a fraction of the overall compound space, and for changes in the specified frequency E. The cause and implications for this systematic skew are subsequently discussed. When generating random libraries of chemical fingerprints, the imposition of a uniqueness requirement should either be avoided or taken into account.
A Novel Least Significant Bit First Processing Parallel CRC Circuit
Directory of Open Access Journals (Sweden)
Xiujie Qu
2013-01-01
Full Text Available In HDLC serial communication protocol, CRC calculation can first process the most or least significant bit of data. Nowadays most CRC calculation is based on the most significant bit (MSB first processing. An algorithm of the least significant bit (LSB first processing parallel CRC is proposed in this paper. Based on the general expression of the least significant bit first processing serial CRC, using state equation method of linear system, we derive a recursive formula by the mathematical deduction. The recursive formula is applicable to any number of bits processed in parallel and any series of generator polynomial. According to the formula, we present the parallel circuit of CRC calculation and implement it with VHDL on FPGA. The results verify the accuracy and effectiveness of this method.
Gravitons, inflatons, twisted bits: A noncommutative bestiary
Pearson, John
In this work, we examine ideas connected with the noncommutativity of spacetime and its realizations in string theory. Motivated by Matrix Theory and the AdS-CFT correspondence, we propose a survey of selected noncommutative objects, assessing their implications for inflation, gauge theory duals, and solvable backgrounds. Our initial pair of examples, related to the Myers effect, incorporate elements of so-called "giant graviton" behavior. In the first, the formation of an extended, supersymmetry-restoring domain wall from point-brane sources in a flux background is related to a nonperturbative process of brane-flux annihilation. In the second, we reexamine these phenomena from a cosmological vantage, investigating the prospect of slow-roll inflation in the noncommutative configuration space of multiple d-branes. For our third and final example, we turn to the solvable pp-wave background, outlining a combinatorial, permutation-based approach to string physics which interpolates between gauge theory and worldsheet methods. This "string bit" language will allow us to find exact agreement between Yang-Mills theory in the large R-charge sector and string field theory on the light cone, resolving some previous discrepancies in the literature.
Notes on Bit-reversal Broadcast Scheduling
Kik, Marcin
2012-01-01
This report contains revision and extension of some results about RBO [arXiv:1108.5095]. RBO is a simple and efficient broadcast scheduling of $n = 2^k$ uniform frames for battery powered radio receivers. Each frame contains a key from some arbitrary linearly ordered universe. The broadcast cycle -- a sequence of frames sorted by the keys and permuted by $k$-bit reversal -- is transmitted in a round robin fashion by the broadcaster. At arbitrary time during the transmission, the receiver may start a simple protocol that reports to him all the frames with the keys that are contained in a specified interval of the key values $[K', K"]$. RBO receives at most $2 k + 1$ other frames' keys before receiving the first key from $[K', K"]$ or noticing that there are no such keys in the broadcast cycle. As a simple corollary, $4 k + 2$ is upper bound the number of keys outside $[K', K"]$ that will ever be received. In unreliable network the expected number of efforts to receive such frames is bounded by $(8 k + 4) / p +...
2010-01-01
On Monday 18 October, a little bit of legal history will be made when the first international tripartite agreement between CERN and its two Host States is signed. This agreement, which has been under negotiation since 2004, clarifies the working conditions of people employed by companies contracted to CERN. It will facilitate the management of service contracts both for CERN and its contractors. Ever since 1965, when CERN first crossed the border into France, the rule of territoriality has applied. This means that anyone working for a company contracted to CERN whose job involves crossing the border is subject to the employment legislation of both states. The new agreement simplifies matters by making only one legislation apply per contract, that of the country in which most of the work is carried out. This is good for CERN, it’s good for the companies, and it’s good for their employees. It is something that all three parties to the agreement have wanted for some time, and I...
Beamlet focal plane diagnostic
Energy Technology Data Exchange (ETDEWEB)
Caird, J.A.; Nielsen, N.D.; Patton, H.G.; Seppala, L.G.; Thompson, C.E.; Wegner, P.J.
1996-12-01
This paper describes the major optical and mechanical design features of the Beamlet Focal Plane Diagnostic system as well as measurements of the system performance, and typical data obtained to date. We also discuss the NIF requirements on the focal spot that we are interested in measuring, and some of our plans for future work using this system.
A 485ps 64-Bit Parallel Adder in 0.18μm CMOS
Institute of Scientific and Technical Information of China (English)
Dong-Yu Zheng; Yan Sun; Shao-Qing Li; Liang Fang
2007-01-01
This paper presents an optimized 64-bit parallel adder.Sparse-tree architecture enables low carry-merge fan-outs and inter-stage wiring complexity.Single-rail and semi-dynamic circuit improves operation speed.Simulation results show that the proposed adder can operate at 485ps with power of 25.6mW in 0.18μm CMOS process.It achieves the goal of higher speed and lower power.
The Application Wavelet Transform Algorithm in Testing ADC Effective Number of Bits
Directory of Open Access Journals (Sweden)
Emad A. Awada
2013-10-01
Full Text Available In evaluating Analog to Digital Convertors, many parameters are checked for performance and error rate.One of these parameters is the device Effective Number of Bits. In classical testing of Effective Number ofBits, testing is based on signal to noise components ratio (SNR, whose coefficients are driven viafrequency domain (Fourier Transform of ADC’s output signal. Such a technique is extremely sensitive tonoise and require large number of data samples. That is, longer and more complex testing process as thedevice under test increases in resolutions. Meanwhile, a new time – frequency domain approach (known asWavelet transform is proposed to measure and analyze Analog-to-Digital Converters parameter ofEffective Number of Bits with less complexity and fewer data samples.In this work, the algorithm of Wavelet transform was used to estimate worst case Effective Number of Bitsand compare the new testing results with classical testing methods. Such an algorithm, Wavelet transform,have shown DSP testing process improvement in terms of time and computations complexity based on itsspecial properties of multi-resolutions.
Modeling and analysis of stick-slip and bit bounce in oil well drillstrings equipped with drag bits
Kamel, Jasem M.; Yigit, Ahmet S.
2014-12-01
Rotary drilling systems equipped with drag bits or fixed cutter bits (also called PDC), used for drilling deep boreholes for the production and the exploration of oil and natural gas, often suffer from severe vibrations. These vibrations are detrimental to the bit and the drillstring causing different failures of equipment (e.g., twist-off, abrasive wear of tubulars, bit damage), and inefficiencies in the drilling operation (reduction of the rate of penetration (ROP)). Despite extensive research conducted in the last several decades, there is still a need to develop a consistent model that adequately captures all phenomena related to drillstring vibrations such as nonlinear cutting and friction forces at the bit/rock formation interface, drive system characteristics and coupling between various motions. In this work, a physically consistent nonlinear model for the axial and torsional motions of a rotating drillstring equipped with a drag bit is proposed. A more realistic cutting and contact model is used to represent bit/rock formation interaction at the bit. The dynamics of both drive systems for rotary and translational motions of the drillstring, including the hoisting system are also considered. In this model, the rotational and translational motions of the bit are obtained as a result of the overall dynamic behavior rather than prescribed functions or constants. The dynamic behavior predicted by the proposed model qualitatively agree well with field observations and published theoretical results. The effects of various operational parameters on the dynamic behavior are investigated with the objective of achieving a smooth and efficient drilling. The results show that with proper choice of operational parameters, it may be possible to minimize the effects of stick-slip and bit-bounce and increase the ROP. Therefore, it is expected that the results will help reduce the time spent in drilling process and costs incurred due to severe vibrations and consequent
Modern X86 assembly language programming 32-bit, 64-bit, SSE, and AVX
Kusswurm, Daniel
2014-01-01
Modern X86 Assembly Language Programming shows the fundamentals of x86 assembly language programming. It focuses on the aspects of the x86 instruction set that are most relevant to application software development. The book's structure and sample code are designed to help the reader quickly understand x86 assembly language programming and the computational capabilities of the x86 platform. Major topics of the book include the following: 32-bit core architecture, data types, internal registers, memory addressing modes, and the basic instruction setX87 core architecture, register stack, special
Test results judgment method based on BIT faults
Institute of Scientific and Technical Information of China (English)
Wang Gang; Qiu Jing; Liu Guanjun; Lyu Kehong
2015-01-01
Built-in-test (BIT) is responsible for equipment fault detection, so the test data correct-ness directly influences diagnosis results. Equipment suffers all kinds of environment stresses, such as temperature, vibration, and electromagnetic stress. As embedded testing facility, BIT also suffers from these stresses and the interferences/faults are caused, so that the test course is influenced, resulting in incredible results. Therefore it is necessary to monitor test data and judge test failures. Stress monitor and BIT self-diagnosis would redound to BIT reliability, but the existing anti-jamming researches are mainly safeguard design and signal process. This paper focuses on test results monitor and BIT equipment (BITE) failure judge, and a series of improved approaches is proposed. Firstly the stress influences on components are illustrated and the effects on the diagnosis results are summarized. Secondly a composite BIT program is proposed with information integra-tion, and a stress monitor program is given. Thirdly, based on the detailed analysis of system faults and forms of BIT results, the test sequence control method is proposed. It assists BITE failure judge and reduces error probability. Finally the validation cases prove that these approaches enhance credibility.
Evaluation of bit errors in different types demodulation discrete signals
Directory of Open Access Journals (Sweden)
V. M. Kychak
2015-12-01
Full Text Available Introduction. The introduction describes the main characteristics of bit errors. These sources of bit errors in discrete channels. Also listed scientists who worked on the study opportunities monitoring bit error in discrete channels. The main purpose of the article is to conduct research and theoretical modeling of processes in discrete channels to control error measurement and forecasting parameter BER bit error depending on the signal/noise ratio. Theoretical analysis. A comparison of some types of digital modulation for effective use in systems transmitting information. Comparisons were made using the correlation function, power spectral density and distance between signals. It was proved that through this you can control the real value of bit error (BER for each type of modulation. Important here is the dependence of the BER signal/noise ratio in the test communication channel. Determined that efficiency could be described bit error probability value of the output of the receiver, which is determined by the expression (4. Control parameters BER modulation in digital signals. At this paragraph the examples of control parameter BER at different modulation signals. The simulation results show that with an increase in the signal/noise bit error probability for different types of demodulation will decrease.
Gershenson, Carlos
2011-01-01
The term complexity derives etymologically from the Latin plexus, which means interwoven. Intuitively, this implies that something complex is composed by elements that are difficult to separate. This difficulty arises from the relevant interactions that take place between components. This lack of separability is at odds with the classical scientific method - which has been used since the times of Galileo, Newton, Descartes, and Laplace - and has also influenced philosophy and engineering. In recent decades, the scientific study of complexity and complex systems has proposed a paradigm shift in science and philosophy, proposing novel methods that take into account relevant interactions.
Directory of Open Access Journals (Sweden)
Efim Khalimsky
1990-01-01
Full Text Available The importance of topological connectedness properties in processing digital pictures is well known. A natural way to begin a theory for this is to give a definition of connectedness for subsets of a digital plane which allows one to prove a Jordan curve theorem. The generally accepted approach to this has been a non-topological Jordan curve theorem which requires two different definitions, 4-connectedness, and 8-connectedness, one for the curve and the other for its complement.
Energy Technology Data Exchange (ETDEWEB)
Foda, Omar; Wheeler, Michael [Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010 (Australia)
2007-01-15
Using BKP neutral fermions, we derive a product expression for the generating function of volume-weighted plane partitions that satisfy two conditions. If we call a set of adjacent equal height-h columns, h > 0, an h-path, then 1. Every h-path can assume one of two possible colours. 2. There is a unique way to move along an h-path from any column to another.
The Economics of BitCoin Price Formation
Ciaian, Pavel; Rajcaniova, Miroslava; Kancs, d'Artis
2014-01-01
This is the first article that studies BitCoin price formation by considering both the traditional determinants of currency price, e.g., market forces of supply and demand, and digital currencies specific factors, e.g., BitCoin attractiveness for investors and users. The conceptual framework is based on the Barro (1979) model, from which we derive testable hypotheses. Using daily data for five years (2009–2015) and applying time-series analytical mechanisms, we find that market forces and Bit...
AN EFFICIENT BIT COMMITMENT SCHEME BASED ON FACTORING ASSUMPTION
Institute of Scientific and Technical Information of China (English)
Zhong Ming; Yang Yixian
2001-01-01
Recently, many bit commitment schemes have been presented. This paper presents a new practical bit commitment scheme based on Schnorr's one-time knowledge proof scheme,where the use of cut-and-choose method and many random exam candidates in the protocols are replaced by a single challenge number. Therefore the proposed bit commitment scheme is more efficient and practical than the previous schemes In addition, the security of the proposed scheme under factoring assumption is proved, thus the cryptographic basis of the proposed scheme is clarified.
Unconditionally secure bit commitment by transmitting measurement outcomes.
Kent, Adrian
2012-09-28
We propose a new unconditionally secure bit commitment scheme based on Minkowski causality and the properties of quantum information. The receiving party sends a number of randomly chosen Bennett-Brassard 1984 (BB84) qubits to the committer at a given point in space-time. The committer carries out measurements in one of the two BB84 bases, depending on the committed bit value, and transmits the outcomes securely at (or near) light speed in opposite directions to remote agents. These agents unveil the bit by returning the outcomes to adjacent agents of the receiver. The protocol's security relies only on simple properties of quantum information and the impossibility of superluminal signalling.
Unconditionally Secure Bit Commitment by Transmitting Measurement Outcomes
,
2011-01-01
We propose a new unconditionally secure bit commitment scheme based on Minkowski causality and the properties of quantum information. The receiving party sends a number of randomly chosen BB84 qubits to the committer at a given point in space-time. The committer carries out measurements in one of the two BB84 bases, depending on the committed bit value, and transmits the outcomes securely at light speed in opposite directions to remote agents. These agents unveil the bit by returning the outcomes to adjacent agents of the receiver. The security proofs rely only on simple properties of quantum information and the impossibility of superluminal signalling.
1-Bit Compressive Data Gathering for Wireless Sensor Networks
Directory of Open Access Journals (Sweden)
Jiping Xiong
2014-01-01
Full Text Available Compressive sensing (CS has been widely used in wireless sensor networks for the purpose of reducing the data gathering communication overhead in recent years. In this paper, we firstly apply 1-bit compressive sensing to wireless sensor networks to further reduce the communication overhead that each sensor needs to send. Furthermore, we propose a novel blind 1-bit CS reconstruction algorithm which outperforms other state-of-the-art blind 1-bit CS reconstruction algorithms under the settings of WSN. Experimental results on real sensor datasets demonstrate the efficiency of our method.
Video Synchronization With Bit-Rate Signals and Correntropy Function
Directory of Open Access Journals (Sweden)
Igor Pereira
2017-09-01
Full Text Available We propose an approach for the synchronization of video streams using correntropy. Essentially, the time offset is calculated on the basis of the instantaneous transfer rates of the video streams that are extracted in the form of a univariate signal known as variable bit-rate (VBR. The state-of-the-art approach uses a window segmentation strategy that is based on consensual zero-mean normalized cross-correlation (ZNCC. This strategy has an elevated computational complexity, making its application to synchronizing online data streaming difficult. Hence, our proposal uses a different window strategy that, together with the correntropy function, allows the synchronization to be performed for online applications. This provides equivalent synchronization scores with a rapid offset determination as the streams come into the system. The efficiency of our approach has been verified through experiments that demonstrate its viability with values that are as precise as those obtained by ZNCC. The proposed approach scored 81 % in time reference classification against the equivalent 81 % of the state-of-the-art approach, requiring much less computational power.
Image plane sweep volume illumination.
Sundén, Erik; Ynnerman, Anders; Ropinski, Timo
2011-12-01
In recent years, many volumetric illumination models have been proposed, which have the potential to simulate advanced lighting effects and thus support improved image comprehension. Although volume ray-casting is widely accepted as the volume rendering technique which achieves the highest image quality, so far no volumetric illumination algorithm has been designed to be directly incorporated into the ray-casting process. In this paper we propose image plane sweep volume illumination (IPSVI), which allows the integration of advanced illumination effects into a GPU-based volume ray-caster by exploiting the plane sweep paradigm. Thus, we are able to reduce the problem complexity and achieve interactive frame rates, while supporting scattering as well as shadowing. Since all illumination computations are performed directly within a single rendering pass, IPSVI does not require any preprocessing nor does it need to store intermediate results within an illumination volume. It therefore has a significantly lower memory footprint than other techniques. This makes IPSVI directly applicable to large data sets. Furthermore, the integration into a GPU-based ray-caster allows for high image quality as well as improved rendering performance by exploiting early ray termination. This paper discusses the theory behind IPSVI, describes its implementation, demonstrates its visual results and provides performance measurements.
Engineering Dissipation to Generate Entanglement Between Remote Superconducting Quantum Bits
Schwartz, Mollie Elisheva
Superconducting quantum circuits provide a promising avenue for scalable quantum computation and simulation. Their chief advantage is that, unlike physical atoms or electrons, these ''artificial atoms'' can be designed with nearly-arbitrarily large coupling to one another and to their electromagnetic environment. This strong coupling allows for fast quantum bit (qubit) operations, and for efficient readout. However, strong coupling comes at a price: a qubit that is strongly coupled to its environment is also strongly susceptible to losses and dissipation, as coherent information leaks from the quantum system under study into inaccessible ''bath'' modes. Extensive work in the field is dedicated to engineering away these losses to the extent possible, and to using error correction to undo the effects of losses that are unavoidable. This dissertation explores an alternate approach to dissipation: we study avenues by which dissipation itself can be used to generate, rather than destroy, quantum resources. We do so specifically in the context of quantum entanglement, one of the most important and most counter-intuitive aspects of quantum mechanics. Entanglement generation and stabilization is critical to most non-trivial implementations of quantum computing and quantum simulation, as it is the property that distinguishes a multi-qubit quantum system from a string of classical bits. The ability to harness dissipation to generate, purify, and stabilize entanglement is therefore highly desirable. We begin with an overview of quantum dissipation and measurement, followed by an introduction to entanglement and to the superconducting quantum information architecture. We then discuss three sets of experiments that highlight and explore the powerful uses of dissipation in quantum systems. First, we use an entangling measurement to probabilistically generate entanglement between two qubits separated by more than one meter of ordinary cable. This represents the first achievement
Institute of Scientific and Technical Information of China (English)
Liu Weidong; Zhu Hua; Wang Yiping; Zhou Shengqiang; Bai Yalei; Zhao Chunsheng
2013-01-01
Non-dominated sorting genetic algorithm II (NSGA-II) with multiple constraints han-dling is employed for multi-objective optimization of the topological structure of telescope skin, in which a bit-matrix is used as the representation of a chromosome, and genetic algorithm (GA) operators are introduced based on the matrix. Objectives including mass, in-plane performance, and out-of-plane load-bearing ability of the individuals are obtained by finite element analysis (FEA) using ANSYS, and the matrix-based optimization algorithm is realized in MATLAB by han-dling multiple constraints such as structural connectivity and in-plane strain requirements. Feasible configurations of the support structure are achieved. The results confirm that the matrix-based NSGA-II with multiple constraints handling provides an effective method for two-dimensional multi-objective topology optimization.
Comparison between GEOCOR IV SIGN-BIT an DFS-V 16-bit floating point recording systems
Energy Technology Data Exchange (ETDEWEB)
Hollis, D.D.; Givens, R.
1986-04-01
A Vibroseis line was repeatedly shot in Andrews County, Texas. The first shot used a DFS-V 16-bit floating point recording system with parameters optimized for that particular recording system and subsurface geology. Then the line was shot with a GEOCOR IV SIGN-BIT recording system, once using the same parameters as on the floating point recording system, then with parameters optimized for a SIGN-BIT recording system - mainly higher fold, closer channel spacing, and using the VARISWEEP technique. The three lines were processed to stacked sections using identical processing parameters. When the 16-bit floating point recording system is compared to the SIGN-BIT system with identical parameters, the results indicate the systems are equivalent for Vibroseis recording. Basic primary reflections are similar in signal to noise and frequency. Multiple reflection energy is greater on the floating point section. However, the results differ when the two systems are compared using optimal parameters for each system. The SIGN-BIT section had shallower data because the receiver line has no gapping. The SIGN-BIT system also had better temporal and spatial resolution because channel spacing was reduced and a different sweep technique was used.
Berry, Edward A; Walker, F Ann
2008-05-01
Early investigation of the electron paramagnetic resonance spectra of bis-histidine-coordinated membrane-bound ferriheme proteins led to the description of a spectral signal that had only one resolved feature. These became known as "highly anisotropic low-spin" or "large g(max)" ferriheme centers. Extensive work with small-molecule model heme complexes showed that this spectroscopic signature occurs in bis-imidazole ferrihemes in which the planes of the imidazole ligands are nearly perpendicular, deltaphi = 57-90 degrees. In the last decade protein crystallographic studies have revealed the atomic structures of a number of examples of bis-histidine heme proteins. A frequent characteristic of these large g(max) ferrihemes in membrane-bound proteins is the occurrence of the heme within a four-helix bundle with a left-handed twist. The histidine ligands occur at the same level on two diametrically opposed helices of the bundle. These ligands have the same side-chain conformation and ligate heme iron on the bundle axis, resulting in a quasi-twofold symmetric structure. The two non-ligand-bearing helices also obey this symmetry, and have a conserved small residue, usually glycine, where the edge of the heme ring makes contact with the helix backbones. In many cases this small residue is preceded by a threonine or serine residue whose side-chain hydroxyl oxygen acts as a hydrogen-bond acceptor from the N(delta1) atom of the heme-ligating histidine. The deltaphi angle is thus determined by the common histidine side-chain conformation and the crossing angle of the ligand-bearing helices, in some cases constrained by hydrogen bonds to the serine/threonine residues on the non-ligand-bearing helices.
Experimental bit commitment based on quantum communication and special relativity.
Lunghi, T; Kaniewski, J; Bussières, F; Houlmann, R; Tomamichel, M; Kent, A; Gisin, N; Wehner, S; Zbinden, H
2013-11-01
Bit commitment is a fundamental cryptographic primitive in which Bob wishes to commit a secret bit to Alice. Perfectly secure bit commitment between two mistrustful parties is impossible through asynchronous exchange of quantum information. Perfect security is however possible when Alice and Bob split into several agents exchanging classical and quantum information at times and locations suitably chosen to satisfy specific relativistic constraints. Here we report on an implementation of a bit commitment protocol using quantum communication and special relativity. Our protocol is based on [A. Kent, Phys. Rev. Lett. 109, 130501 (2012)] and has the advantage that it is practically feasible with arbitrary large separations between the agents in order to maximize the commitment time. By positioning agents in Geneva and Singapore, we obtain a commitment time of 15 ms. A security analysis considering experimental imperfections and finite statistics is presented.
Apparatus and method for situ sharpening of bore hole bits
Energy Technology Data Exchange (ETDEWEB)
Bridwell, H.C.
1974-06-25
An impregnated diamond core bit is sharpened at the bottom of a borehole, the bit being secured to the outer barrel of coring apparatus attached to a tubular drill string. A sharpener is releasably mounted in the lower end of an inner core barrel lowered through the drill string into the outer barrel and latched thereto, with the sharpener projecting below the lower end of the core bit. The sharpener has nozzles for discharging abrasive material pumped through the sharpener against the drilling face of the bit to sharpen the same, whereupon the coring operation can be effected in the usual manner, the core releasing the sharpener from the inner barrel and pushing it upward along and within the inner barrel as the core is formed. The sharpener is rtrieved with the inner barrel upon release of the latter from the outer barrel and its upward removal through the drill string to the top of the borehole. (29 claims)
Bit-interleaved coded modulation in the wideband regime
Martinez, Alfonso; Caire, Giuseppe; Willems, Frans
2007-01-01
The wideband regime of bit-interleaved coded modulation (BICM) in Gaussian channels is studied. The Taylor expansion of the coded modulation capacity for generic signal constellations at low signal-to-noise ratio (SNR) is derived and used to determine the corresponding expansion for the BICM capacity. Simple formulas for the minimum energy per bit and the wideband slope are given. BICM is found to be suboptimal in the sense that its minimum energy per bit can be larger than the corresponding value for coded modulation schemes. The minimum energy per bit using standard Gray mapping on M-PAM or M^2-QAM is given by a simple formula and shown to approach -0.34 dB as M increases. Using the low SNR expansion, a general trade-off between power and bandwidth in the wideband regime is used to show how a power loss can be traded off against a bandwidth gain.
Efficient Generation of Random Bits from Finite State Markov Chains
Zhou, Hongchao
2010-01-01
The problem of random number generation from an uncorrelated random source (of unknown probability distribution) dates back to von Neumann's 1951 work. Elias (1972) generalized von Neumann's scheme and showed how to achieve optimal efficiency in unbiased random bits generation. Hence, a natural question is what if the sources are correlated? Both Elias and Samuelson proposed methods for generating unbiased random bits in the case of correlated sources (of unknown probability distribution), specifically, they considered finite Markov chains. However, their proposed methods are not efficient or have implementation difficulties. Blum (1986) devised an algorithm for efficiently generating random bits from degree-2 finite Markov chains in expected linear time, however, his beautiful method is still far from optimality on information-efficiency. In this paper, we generalize Blum's algorithm to arbitrary degree finite Markov chains and combine it with Elias's method for efficient generation of unbiased bits. As a re...
A NEW LABELING SEARCH ALGORITHM FOR BIT-INTERLEAVED CODED MODULATION WITH ITERATIVE DECODING
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
Bit-Interleaved Coded Modulation with Iterative Decoding (BICM-ID) is a bandwidth efficient transmission, where the bit error rate is reduced through the iterative information exchange between the inner demapper and the outer decoder. The choice of the symbol mapping is the crucial design parameter. This paper indicates that the Harmonic Mean of the Minimum Squared Euclidean (HMMSE) distance is the best criterion for the mapping design. Based on the design criterion of the HMMSE distance, a new search algorithm to find the optimized labeling maps for BICM-ID system is proposed. Numerical results and performance comparison show that the new labeling search method has a low complexity and outperforms other labeling schemes using other design criterion in BICM-ID system, therefore it is an optimized labeling method.
Numerical optimization of writer and media for bit patterned magnetic recording
Kovacs, A; Schabes, M E; Schrefl, T
2016-01-01
In this work we present a micromagnetic study of the performance potential of bit-patterned (BP) magnetic recording media via joint optimization of the design of the media and of the magnetic write heads. Because the design space is large and complex, we developed a novel computational framework suitable for parallel implementation on compute clusters. Our technique combines advanced global optimization algorithms and finite-element micromagnetic solvers. Targeting data bit densities of $4\\mathrm{Tb}/\\mathrm{in}^2$, we optimize designs for centered, staggered, and shingled BP writing. The magnetization dynamics of the switching of the exchange-coupled composite BP islands of the media is treated micromagnetically. Our simulation framework takes into account not only the dynamics of on-track errors but also of the thermally induced adjacent-track erasure. With co-optimized write heads, the results show superior performance of shingled BP magnetic recording where we identify two particular designs achieving wri...
Directory of Open Access Journals (Sweden)
S. Chris Prema
2015-01-01
Full Text Available A rate request sequenced bit loading reallocation algorithm is proposed. The spectral holes detected by spectrum sensing (SS in cognitive radio (CR are used by secondary users. This algorithm is applicable to Discrete Multitone (DMT systems for secondary user reallocation. DMT systems support different modulation on different subchannels according to Signal-to-Noise Ratio (SNR. The maximum bits and power that can be allocated to each subband is determined depending on the channel state information (CSI and secondary user modulation scheme. The spectral holes or free subbands are allocated to secondary users depending on the user rate request and subchannel capacity. A comparison is done between random rate request and sequenced rate request of secondary user for subchannel allocation. Through simulations it is observed that with sequenced rate request higher spectral efficiency is achieved with reduced complexity.
Design of High Speed 128 bit Parallel Prefix Adders
T.KIRAN KUMAR; Srikanth, P
2014-01-01
In this paper, we propose 128-bit Kogge-Stone, Ladner-Fischer, Spanning tree parallel prefix adders and compared with Ripple carry adder. In general N-bit adders like Ripple Carry Adders (slow adders compare to other adders), and Carry Look Ahead adders (area consuming adders) are used in earlier days. But now the most Industries are using parallel prefix adders because of their advantages compare to other adders. Parallel prefix adders are faster and area efficient. Parallel pref...
Unconditionally secure quantum bit commitment really is impossible
Bub, J
2001-01-01
Unconditionally secure quantum bit commitment has been shown to be impossible by Mayers (PRL 78, 3414 (1997)) and Lo and Chau (PRL 78, 3410 (1997)) but the claim is repeatedly challenged. The bit commitment theorem is reviewed here and the central conceptual point, that an 'Einstein-Podolsky-Rosen' attack or cheating strategy can always be applied, is clarified. The question of whether following such a cheating strategy can ever be disadvantageous to the cheater is considered and answered in the negative.
Content Progressive Coding of Limited Bits/pixel Images
DEFF Research Database (Denmark)
Jensen, Ole Riis; Forchhammer, Søren
1999-01-01
A new lossless context based method for content progressive coding of limited bits/pixel images is proposed. Progressive coding is achieved by separating the image into contelnt layers. Digital maps are compressed up to 3 times better than GIF.......A new lossless context based method for content progressive coding of limited bits/pixel images is proposed. Progressive coding is achieved by separating the image into contelnt layers. Digital maps are compressed up to 3 times better than GIF....
Exponential speed-up with a single bit of quantum information: Testing the quantum butterfly effect
Poulin, D; Laflamme, R; Ollivier, H; Poulin, David; Blume-Kohout, Robin; Laflamme, Raymond; Ollivier, Harold
2003-01-01
We present an efficient quantum algorithm to measure the average fidelity decay of a quantum map under perturbation using a single bit of quantum information. Our algorithm scales only as the complexity of the map under investigation, so for those maps admitting an efficient gate decomposition, it provides an exponential speed up over known classical procedures. Fidelity decay is important in the study of complex dynamical systems, where it is conjectured to be a signature of quantum chaos. Our result also illustrates the role of chaos in the process of decoherence.
African Journals Online (AJOL)
CLEMENT O BEWAJI
Schiff bases and their complex compounds have been studied for their .... establishing coordination of the N–(2 – hydroxybenzyl) - L - α - valine Schiff base ..... (1967); “Spectrophotometric Identification of Organic Compounds”, Willey, New.
Monocle: Dynamic, Fine-Grained Data Plane Monitoring
Peresini, Peter; Kuzniar, Maciej; Kostic, Dejan
2015-01-01
Ensuring network reliability is important for satisfying service-level objectives. However, diagnosing network anomalies in a timely fashion is difficult due to the complex nature of network configurations. We present Monocle — a system that uncovers forwarding problems due to hardware or software failures in switches, by verifying that the data plane corresponds to the view that an SDN controller installs via the control plane. Monocle works by systematically probing the switch data plane; t...
Johnson, Aylmer
2004-01-01
Plane and Geodetic Surveying blends theory and practice, conventional techniques and GPS, to provide the ideal book for students of surveying.Detailed guidance is given on how and when the principle surveying instruments (theodolites, Total Stations, levels and GPS) should be used. Concepts and formulae needed to convert instrument readings into useful results are explained. Rigorous explanations of the theoretical aspects of surveying are given, while at the same time a wealth of useful advice about conducting a survey in practice is provided. An accompanying least squares adjustment program
Hash Based Least Significant Bit Technique For Video Steganography
Directory of Open Access Journals (Sweden)
Prof. Dr. P. R. Deshmukh ,
2014-01-01
Full Text Available The Hash Based Least Significant Bit Technique For Video Steganography deals with hiding secret message or information within a video.Steganography is nothing but the covered writing it includes process that conceals information within other data and also conceals the fact that a secret message is being sent.Steganography is the art of secret communication or the science of invisible communication. In this paper a Hash based least significant bit technique for video steganography has been proposed whose main goal is to embed a secret information in a particular video file and then extract it using a stego key or password. In this Least Significant Bit insertion method is used for steganography so as to embed data in cover video with change in the lower bit.This LSB insertion is not visible.Data hidding is the process of embedding information in a video without changing its perceptual quality. The proposed method involve with two terms that are Peak Signal to Noise Ratio (PSNR and the Mean Square Error (MSE .This two terms measured between the original video files and steganographic video files from all video frames where a distortion is measured using PSNR. A hash function is used to select the particular position for insertion of bits of secret message in LSB bits.
Characterization and modeling of fast programming bits in flash EEPROM
Nkansah, F.; Hatalis, M.; Olasupo, K.
2000-11-01
The effects of flash EEPROM floating gate (FG) morphology on the generation and density of fast programming bits in a 2Mbit flash EEPROM array has been characterized. These fast programming bits exhibit identical subthreshold characteristics similar to that of a normal bit after UV erase, thus establishing that the initial charge stored on the FG of both fast and normal bit is the same. Experimental results clearly indicates that the fast programming phenomena result from an interaction of the programming process with the FG polysilicon microstructure. An in-depth experimentation previously reported, reveals that the FG poly deposition and doping processes are crucial for controlling the desired Fowler-Nordheim tunneling. A correlation is established between the fast bit density observed in the memory arrays, the FG polysilicon grain size and tunneling field enhancement factor μ( Rc). A compact model of the fast programming bit memory threshold voltage as a function of the effective FG polysilicon grain area factor Geff, and tunneling field enhancement factor μ( Rc) has been developed for the first time.
Bamatraf, Abdullah; Salleh, Mohd Najib Mohd
2011-01-01
In this paper, we introduce a new digital watermarking algorithm using least significant bit (LSB). LSB is used because of its little effect on the image. This new algorithm is using LSB by inversing the binary values of the watermark text and shifting the watermark according to the odd or even number of pixel coordinates of image before embedding the watermark. The proposed algorithm is flexible depending on the length of the watermark text. If the length of the watermark text is more than ((MxN)/8)-2 the proposed algorithm will also embed the extra of the watermark text in the second LSB. We compare our proposed algorithm with the 1-LSB algorithm and Lee's algorithm using Peak signal-to-noise ratio (PSNR). This new algorithm improved its quality of the watermarked image. We also attack the watermarked image by using cropping and adding noise and we got good results as well.
Liu, Yan; Fan, Xi; Chen, Houpeng; Wang, Yueqing; Liu, Bo; Song, Zhitang; Feng, Songlin
2017-08-01
In this brief, multilevel data storage for phase-change memory (PCM) has attracted more attention in the memory market to implement high capacity memory system and reduce cost-per-bit. In this work, we present a universal programing method of SET stair-case current pulse in PCM cells, which can exploit the optimum programing scheme to achieve 2-bit/ 4state resistance-level with equal logarithm interval. SET stair-case waveform can be optimized by TCAD real time simulation to realize multilevel data storage efficiently in an arbitrary phase change material. Experimental results from 1 k-bit PCM test-chip have validated the proposed multilevel programing scheme. This multilevel programming scheme has improved the information storage density, robustness of resistance-level, energy efficient and avoiding process complexity.
Hackel, L.A.; Hermann, M.R.; Dane, C.B.; Tiszauer, D.H.
1995-12-12
A solid state laser is frequency tripled to 0.3 {micro}m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only about 1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power. 1 fig.
Zahm, A F
1924-01-01
This report gives the description and the use of a specially designed aerodynamic plane table. For the accurate and expeditious geometrical measurement of models in an aerodynamic laboratory, and for miscellaneous truing operations, there is frequent need for a specially equipped plan table. For example, one may have to measure truly to 0.001 inch the offsets of an airfoil at many parts of its surface. Or the offsets of a strut, airship hull, or other carefully formed figure may require exact calipering. Again, a complete airplane model may have to be adjusted for correct incidence at all parts of its surfaces or verified in those parts for conformance to specifications. Such work, if but occasional, may be done on a planing or milling machine; but if frequent, justifies the provision of a special table. For this reason it was found desirable in 1918 to make the table described in this report and to equip it with such gauges and measures as the work should require.
Cardone, V F; Diaferio, A; Tortora, C; Molinaro, R
2010-01-01
Modified Newtonian Dynamics (MOND) has been shown to be able to fit spiral galaxy rotation curves as well as giving a theoretical foundation for empirically determined scaling relations, such as the Tully - Fisher law, without the need for a dark matter halo. As a complementary analysis, one should investigate whether MOND can also reproduce the dynamics of early - type galaxies (ETGs) without dark matter. As a first step, we here show that MOND can indeed fit the observed central velocity dispersion $\\sigma_0$ of a large sample of ETGs assuming a simple MOND interpolating functions and constant anisotropy. We also show that, under some assumptions on the luminosity dependence of the Sersic n parameter and the stellar M/L ratio, MOND predicts a fundamental plane for ETGs : a log - linear relation among the effective radius $R_{eff}$, $\\sigma_0$ and the mean effective intensity $\\langle I_e \\rangle$. However, we predict a tilt between the observed and the MOND fundamental planes.
Hackel, Lloyd A.; Hermann, Mark R.; Dane, C. Brent; Tiszauer, Detlev H.
1995-01-01
A solid state laser is frequency tripled to 0.3 .mu.m. A small portion of the laser is split off and generates a Stokes seed in a low power oscillator. The low power output passes through a mask with the appropriate hole pattern. Meanwhile, the bulk of the laser output is focused into a larger stimulated Brillouin scattering (SBS) amplifier. The low power beam is directed through the same cell in the opposite direction. The majority of the amplification takes place at the focus which is the fourier transform plane of the mask image. The small holes occupy large area at the focus and thus are preferentially amplified. The amplified output is now imaged onto the multichip module where the holes are drilled. Because of the fourier plane amplifier, only .about.1/10th the power of a competitive system is needed. This concept allows less expensive masks to be used in the process and requires much less laser power.
A Heuristic Optimal Discrete Bit Allocation Algorithm for Margin Maximization in DMT Systems
Directory of Open Access Journals (Sweden)
Dong Shi-Wei
2007-01-01
Full Text Available A heuristic optimal discrete bit allocation algorithm is proposed for solving the margin maximization problem in discrete multitone (DMT systems. Starting from an initial equal power assignment bit distribution, the proposed algorithm employs a multistaged bit rate allocation scheme to meet the target rate. If the total bit rate is far from the target rate, a multiple-bits loading procedure is used to obtain a bit allocation close to the target rate. When close to the target rate, a parallel bit-loading procedure is used to achieve the target rate and this is computationally more efficient than conventional greedy bit-loading algorithm. Finally, the target bit rate distribution is checked, if it is efficient, then it is also the optimal solution; else, optimal bit distribution can be obtained only by few bit swaps. Simulation results using the standard asymmetric digital subscriber line (ADSL test loops show that the proposed algorithm is efficient for practical DMT transmissions.
Computer Series, 99: Bits and Pieces, 39.
Moore, John W., Ed.
1989-01-01
Presents five computer programs: (1) Accurate Numerical Solutions of the One-Dimensional Schrodinger Equation; (2) NMR Simulation and Interactive Drill/Interpretation; (3) A Simple Computer Program for the Calculation of 13C-NMR Chemical Shifts; (4) Constants of 1:1 Complexes from NMR or Spectrophotometric Measurements; and (5) Saturation…
Roy, Subhadip; Oyarzabal, Itziar; Vallejo, Julia; Cano, Joan; Colacio, Enrique; Bauza, Antonio; Frontera, Antonio; Kirillov, Alexander M; Drew, Michael G B; Das, Subrata
2016-09-06
A mononuclear cobalt(II) complex [Co(3,5-dnb)2(py)2(H2O)2] {3,5-Hdnb = 3,5-dinitrobenzoic acid; py = pyridine} was isolated in two polymorphs, in space groups C2/c (1) and P21/c (2). Single-crystal X-ray diffraction analyses reveal that 1 and 2 are not isostructural in spite of having equal formulas and ligand connectivity. In both structures, the Co(II) centers adopt octahedral {CoN2O4} geometries filled by pairs of mutually trans terminal 3,5-dnb, py, and water ligands. However, the structures of 1 and 2 disclose distinct packing patterns driven by strong intermolecular O-H···O hydrogen bonds, leading to their 0D→2D (1) or 0D→1D (2) extension. The resulting two-dimensional layers and one-dimensional chains were topologically classified as the sql and 2C1 underlying nets, respectively. By means of DFT theoretical calculations, the energy variations between the polymorphs were estimated, and the binding energies associated with the noncovalent interactions observed in the crystal structures were also evaluated. The study of the direct-current magnetic properties, as well as ab initio calculations, reveal that both 1 and 2 present a strong easy-plane magnetic anisotropy (D > 0), which is larger for the latter polymorph (D is found to exhibit values between +58 and 117 cm(-1) depending on the method). Alternating current dynamic susceptibility measurements show that these polymorphs exhibit field-induced slow relaxation of the magnetization with Ueff values of 19.5 and 21.1 cm(-1) for 1 and 2, respectively. The analysis of the whole magnetic data allows the conclusion that the magnetization relaxation in these polymorphs mainly takes place through a virtual excited state (Raman process). It is worth noting that despite the notable difference between the supramolecular networks of 1 and 2, they exhibit almost identical magnetization dynamics. This fact suggests that the relaxation process is intramolecular in nature and that the virtual state involved in the
Geometrically pinned magnetic domain wall for multi-bit per cell storage memory
Bahri, M. Al; Sbiaa, R.
2016-06-01
Spintronic devices currently rely on magnetic switching or controlled motion of domain walls (DWs) by an external magnetic field or a spin-polarized current. Controlling the position of DW is essential for defining the state/information in a magnetic memory. During the process of nanowire fabrication, creating an off-set of two parts of the device could help to pin DW at a precise position. Micromagnetic simulation conducted on in-plane magnetic anisotropy materials shows the effectiveness of the proposed design for pinning DW at the nanoconstriction region. The critical current for moving DW from one state to the other is strongly dependent on nanoconstricted region (width and length) and the magnetic properties of the material. The DW speed which is essential for fast writing of the data could reach values in the range of hundreds m/s. Furthermore, evidence of multi-bit per cell memory is demonstrated via a magnetic nanowire with more than one constriction.
Plane symmetric cosmological models
Yadav, Anil Kumar; Ray, Saibal; Mallick, A
2016-01-01
In this work, we perform the Lie symmetry analysis on the Einstein-Maxwell field equations in plane symmetric spacetime. Here Lie point symmetries and optimal system of one dimensional subalgebras are determined. The similarity reductions and exact solutions are obtained in connection to the evolution of universe. The present study deals with the electromagnetic energy of inhomogeneous universe where $F_{12}$ is the non-vanishing component of electromagnetic field tensor. To get a deterministic solution, it is assumed that the free gravitational field is Petrov type-II non-degenerate. The electromagnetic field tensor $F_{12}$ is found to be positive and increasing function of time. As a special case, to validate the solution set, we discuss some physical and geometric properties of a specific sub-model.
Duality and noncommutative planes
DEFF Research Database (Denmark)
Jøndrup, Søren
2015-01-01
We study extensions of simple modules over an associative ring A and we prove that for twosided ideals mm and nn with artinian factors the condition ExtA1(A/m,A/n)≠0 holds for the left A -modules A/mA/m and A/nA/n if and only if it holds for the right modules A/nA/n and A/mA/m. The methods pro...... proving this are applied to show that noncommutative models of the plane, i.e. algebras of the form k〈x,y〉/(f)k〈x,y〉/(f), where f∈([x,y])f∈([x,y]) are noetherian only in case (f)=([x,y])...
Foldable Instrumented Bits for Ultrasonic/Sonic Penetrators
Bar-Cohen, Yoseph; Badescu, Mircea; Iskenderian, Theodore; Sherrit, Stewart; Bao, Xiaoqi; Linderman, Randel
2010-01-01
Long tool bits are undergoing development that can be stowed compactly until used as rock- or ground-penetrating probes actuated by ultrasonic/sonic mechanisms. These bits are designed to be folded or rolled into compact form for transport to exploration sites, where they are to be connected to their ultrasonic/ sonic actuation mechanisms and unfolded or unrolled to their full lengths for penetrating ground or rock to relatively large depths. These bits can be designed to acquire rock or soil samples and/or to be equipped with sensors for measuring properties of rock or soil in situ. These bits can also be designed to be withdrawn from the ground, restowed, and transported for reuse at different exploration sites. Apparatuses based on the concept of a probe actuated by an ultrasonic/sonic mechanism have been described in numerous prior NASA Tech Briefs articles, the most recent and relevant being "Ultrasonic/ Sonic Impacting Penetrators" (NPO-41666) NASA Tech Briefs, Vol. 32, No. 4 (April 2008), page 58. All of those apparatuses are variations on the basic theme of the earliest ones, denoted ultrasonic/sonic drill corers (USDCs). To recapitulate: An apparatus of this type includes a lightweight, low-power, piezoelectrically driven actuator in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary twist drilling, ordinary hammering, or ordinary steady pushing. Examples of properties that could be measured by use of an instrumented tool bit include electrical conductivity, permittivity, magnetic
Supporting 64-bit global indices in Epetra and other Trilinos packages :
Energy Technology Data Exchange (ETDEWEB)
Jhurani, Chetan; Austin, Travis M.; Heroux, Michael Allen; Willenbring, James Michael
2013-06-01
The Trilinos Project is an effort to facilitate the design, development, integration and ongoing support of mathematical software libraries within an object-oriented framework. It is intended for large-scale, complex multiphysics engineering and scientific applications [2, 4, 3]. Epetra is one of its basic packages. It provides serial and parallel linear algebra capabilities. Before Trilinos version 11.0, released in 2012, Epetra used the C++ int data-type for storing global and local indices for degrees of freedom (DOFs). Since int is typically 32-bit, this limited the largest problem size to be smaller than approximately two billion DOFs. This was true even if a distributed memory machine could handle larger problems. We have added optional support for C++ long long data-type, which is at least 64-bit wide, for global indices. To save memory, maintain the speed of memory-bound operations, and reduce further changes to the code, the local indices are still 32-bit. We document the changes required to achieve this feature and how the new functionality can be used. We also report on the lessons learned in modifying a mature and popular package from various perspectives design goals, backward compatibility, engineering decisions, C++ language features, effects on existing users and other packages, and build integration.
Numerical Study of the Simplest String Bit Model
Chen, Gaoli
2016-01-01
String bit models provide a possible method to formulate string as a discrete chain of point-like string bits. When the bit number $M$ is large, a chain behaves as a continuous string. We study the simplest case that has only one bosonic bit and one fermionic bit. The creation and annihilation operators are adjoint representations of $U\\left(N\\right)$ color group. We show that the supersymmetry reduces the parameter number of a Hamiltonian from seven to three and, at $N=\\infty$, ensures continuous energy spectrum, which implies the emergence of one spatial dimension. The Hamiltonian $H_{0}$ is constructed so that in large $N$ limit it produces a worldsheet spectrum with one grassmann worldsheet field. We concentrate on numerical study of the model in finite $N$. For the Hamiltonian $H_{0}$, we find that the would-be ground energy states disappear at $N=\\left(M-1\\right)/2$ for odd $M\\leq11$. Such a simple pattern is spoiled if $H$ has an additional term $\\xi\\Delta H$ which does not affect the result of $N=\\inf...
DSC and universal bit-level combining for HARQ systems
Directory of Open Access Journals (Sweden)
Lv Tiejun
2011-01-01
Full Text Available Abstract This paper proposes a Dempster -Shafer theory based combining scheme for single-input single-output (SISO systems with hybrid automatic retransmission request (HARQ, referred to as DSC, in which two methods for soft information calculations are developed for equiprobable (EP and non-equiprobable (NEP sources, respectively. One is based on the distance from the received signal to the decision candidate set consisting of adjacent constellation points when the source bits are equiprobable, and the corresponding DSC is regarded as DSC-D. The other is based on the posterior probability of the transmitted signals when the priori probability for the NEP source bits is available, and the corresponding DSC is regarded as DSC-APP. For the diverse EP and NEP source cases, both DSCD and DSC-APP are superior to maximal ratio combining, the so-called optimal combining scheme for SISO systems. Moreover, the robustness of the proposed DSC is illustrated by the simulations performed in Rayleigh channel and AWGN channel, respectively. The results show that the proposed DSC is insensitive to and especially applicable to the fading channels. In addition, a DS detection-aided bit-level DS combining scheme is proposed for multiple-input multiple-output--HARQ systems. The bit-level DS combining is deduced to be a universal scheme, and the traditional log-likelihood-ratio combining is a special case when the likelihood probability is used as bit-level soft information.
Low-bit-rate subband image coding with matching pursuits
Rabiee, Hamid; Safavian, S. R.; Gardos, Thomas R.; Mirani, A. J.
1998-01-01
In this paper, a novel multiresolution algorithm for low bit-rate image compression is presented. High quality low bit-rate image compression is achieved by first decomposing the image into approximation and detail subimages with a shift-orthogonal multiresolution analysis. Then, at the coarsest resolution level, the coefficients of the transformation are encoded by an orthogonal matching pursuit algorithm with a wavelet packet dictionary. Our dictionary consists of convolutional splines of up to order two for the detail and approximation subbands. The intercorrelation between the various resolutions is then exploited by using the same bases from the dictionary to encode the coefficients of the finer resolution bands at the corresponding spatial locations. To further exploit the spatial correlation of the coefficients, the zero trees of wavelets (EZW) algorithm was used to identify the potential zero trees. The coefficients of the presentation are then quantized and arithmetic encoded at each resolution, and packed into a scalable bit stream structure. Our new algorithm is highly bit-rate scalable, and performs better than the segmentation based matching pursuit and EZW encoders at lower bit rates, based on subjective image quality and peak signal-to-noise ratio.
Permanently Secure Quantum Bit Commitment from a Temporary Computation Bound
Kent, A
1997-01-01
Alice is a private citizen whose computational resources are modest. Bob represents a large organisation at the forefront of computational and cryptological research. Bob's computational and cryptanalytic power is unknown to Alice, but Bob can confidently estimate a bound on Alice's ability to carry out a computation that would break a classical bit commitment. Alice wishes to commit a bit to Bob. She requires that he will never be able to decode it unless she chooses to reveal it, but also that if she does he will be confident that her commitment was genuine. We describe here a simple quantum bit commitment scheme which satisfies these criteria. By iterating the scheme, we obtain quantum bit commitment schemes which allow either Alice or Bob to commit bits to the other. These schemes do not contradict Mayers' and Lo and Chau's no-go results: they rely on a temporary computability bound. However, they are permanently secure against cheating by either party, provided only that Alice was not able to break Bob's...
Retrieving Drill Bit Seismic Signals Using Surface Seismometers
Institute of Scientific and Technical Information of China (English)
Linfei Wang; Huaishan Liu; Siyou Tong; Yanxin Yin; Lei Xing; Zhihui Zou; Xiugang Xu
2015-01-01
Seismic while drilling (SWD) is an emerging borehole seismic imaging technique that uses the downhole drill-bit vibrations as seismic source. Without interrupting drilling, SWD technique can make near-real-time images of the rock formations ahead of the bit and optimize drilling operation, with reduction of costs and the risk of drilling. However, the signal to noise ratio (SNR) of surface SWD-data is severely low for the surface acquisition of SWD data. Here, we propose a new method to retrieve the drill-bit signal from the surface data recorded by an array of broadband seismometers. Taking advantages of wavefield analysis, different types of noises are identified and removed from the surface SWD-data, resulting in the significant improvement of SNR. We also optimally synthesize seis-mic response of the bit source, using a statistical cross-coherence analysis to further improve the SNR and retrieve both the drill-bit direct arrivals and reflections which are then used to establish a reverse vertical seismic profile (RVSP) data set for the continuous drilling depth. The subsurface images de-rived from these data compare well with the corresponding images of the three-dimension surface seis-mic survey cross the well.
Why quantum bit committment and quantum coin tossing are impossible?
Lo, H K
1996-01-01
There had been well known claims of ``provably unbreakable'' quantum protocols for bit commitment and coin tossing. However, we, and independently Mayers, showed that all proposed quantum bit commitment (and coin tossing) schemes are, in principle, insecure because the sender, Alice, can always cheat successfully by using an EPR-type of attack and delaying her measurements. One might wonder if secure quantum bit commitment and coin tossing protocols exist at all. Here we prove that an EPR-type of attack by Alice will, in principle, break {\\em any} realistic quantum bit commitment and {\\em ideal} coin tossing scheme. Therefore, provided that Alice has a quantum computer and is capable of storing quantum signals for an arbitrary length of time, all those schemes are insecure. Since bit commitment and coin tossing are useful primitives for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the security of quantum cryptography in the so-called ``post-col...
DC Polarographic and Plane Polarographic investigation of the ...
African Journals Online (AJOL)
Bheema
circuit. D.C., A.C. and Complex Plane Polarographic behavior of copper (II) in ... Experimental parallel capacity 'CP' values are plotted against ... Series Resistance; Imaginary component of Electrode impedance Z''el = Z''; Real component of.
Causes of wear of PDC bits and ways of improving their wear resistance
Timonin, VV; Smolentsev, AS; Shakhtorin, I. O.; Polushin, NI; Laptev, AI; Kushkhabiev, AS
2017-02-01
The scope of the paper encompasses basic factors that influence PDC bit efficiency. Feasible ways of eliminating the negatives are illustrated. The wash fluid flow in a standard bit is modeled, the resultant pattern of the bit washing is analyzed, and the recommendations are made on modification of the PDC bit design.
Comparative Design of 16-Bit Sparse-Tree Rsfq Adder
Directory of Open Access Journals (Sweden)
S. Saddam Hussain
2014-06-01
Full Text Available In this paper, we propse 16-bit sparse tree RSFQ adder (Rapid single flux quantam, kogge-stone adder, carry lookahead adder. In general N-bit adders like Ripple carry adder s(slow adders compare to other adders, and carry lookahead adders(area consuming adders are used in earlier days. But now the most of industries are using parallel prefix adders because of their advantages compare to kogge-stone adder, carry lookahead adder, Our prefix sparse tree adders are faster and area efficient. Parallel prefix adder is a technique for increasing the speed in DSP processor while performing addition. We simulate and synthesis different types of 16-bit sparse tree RSFQ adders using Xilinx ISE10.1i tool, By using these synthesis results, We noted the performance parameters like number of LUT’s and delay. We compare these three adders interms of LUT’s represents area and delay values.
An improved EZBC algorithm based on block bit length
Wang, Renlong; Ruan, Shuangchen; Liu, Chengxiang; Wang, Wenda; Zhang, Li
2011-12-01
Embedded ZeroBlock Coding and context modeling (EZBC) algorithm has high compression performance. However, it consumes large amounts of memory space because an Amplitude Quadtree of wavelet coefficients and other two link lists would be built during the encoding process. This is one of the big challenges for EZBC to be used in real time or hardware applications. An improved EZBC algorithm based on bit length of coefficients was brought forward in this article. It uses Bit Length Quadtree to complete the coding process and output the context for Arithmetic Coder. It can achieve the same compression performance as EZBC and save more than 75% memory space required in the encoding process. As Bit Length Quadtree can quickly locate the wavelet coefficients and judge their significance, the improved algorithm can dramatically accelerate the encoding speed. These improvements are also beneficial for hardware. PACS: 42.30.Va, 42.30.Wb
Decision-fusion-based automated drill bit toolmark correlator
Jones, Brett C.; Press, Michael J.; Guerci, Joseph R.
1999-02-01
This paper describes a recent study conducted to investigate the reproducibility of toolmarks left by drill bits. This paper focuses on the automated analysis aspect of the study, and particularly the advantages of using decision fusion methods in the comparisons. To enable the study to encompass a large number of samples, existing technology was adapted to the task of automatically comparing the test impressions. Advanced forensic pattern recognition algorithms that had been developed for the comparison of ballistic evidence in the DRUGFIRETM system were modified for use in this test. The results of the decision fusion architecture closely matched those obtained by expert visual examination. The study, aided by the improved pattern recognition algorithm, showed that drill bit impressions do contain reproducible marks. In a blind test, the DRUGFIRE pattern recognition algorithm, enhanced with the decision fusion architecture, consistently identified the correct bit as the source of the test impressions.
Comodulation masking release in bit-rate reduction systems
DEFF Research Database (Denmark)
Vestergaard, Martin David; Rasmussen, Karsten Bo; Poulsen, Torben
1999-01-01
It has been suggested that the level dependence of the upper masking slope be utilized in perceptual models in bit-rate reduction systems. However, comodulation masking release (CMR) phenomena lead to a reduction of the masking effect when a masker and a probe signal are amplitude modulated...... with the same frequency. In bit-rate reduction systems the masker would be the audio signal and the probe signal would represent the quantization noise. Masking curves have been determined for sinusoids and 1-Bark-wide noise maskers in order to investigate the risk of CMR, when quantizing depths are fixed.......75. A CMR of up to 10 dB was obtained at a distance of 6 Bark above the masker. The amount of CMR was found to depend on the presentation level of the masker; a higher masker level leads to a higher CMR effect. Hence, the risk of CMR affecting the subjective performance of bit-rate reduction systems cannot...
BitCube: A Bottom-Up Cubing Engineering
Ferro, Alfredo; Giugno, Rosalba; Puglisi, Piera Laura; Pulvirenti, Alfredo
Enhancing on line analytical processing through efficient cube computation plays a key role in Data Warehouse management. Hashing, grouping and mining techniques are commonly used to improve cube pre-computation. BitCube, a fast cubing method which uses bitmaps as inverted indexes for grouping, is presented. It horizontally partitions data according to the values of one dimension and for each resulting fragment it performs grouping following bottom-up criteria. BitCube allows also partial materialization based on iceberg conditions to treat large datasets for which a full cube pre-computation is too expensive. Space requirement of bitmaps is optimized by applying an adaption of the WAH compression technique. Experimental analysis, on both synthetic and real datasets, shows that BitCube outperforms previous algorithms for full cube computation and results comparable on iceberg cubing.
Framed bit error rate testing for 100G ethernet equipment
DEFF Research Database (Denmark)
Rasmussen, Anders; Ruepp, Sarah Renée; Berger, Michael Stübert
2010-01-01
The Internet users behavioural patterns are migrating towards bandwidth-intensive applications, which require a corresponding capacity extension. The emerging 100 Gigabit Ethernet (GE) technology is a promising candidate for providing a ten-fold increase of todays available Internet transmission...... rate. As the need for 100 Gigabit Ethernet equipment rises, so does the need for equipment, which can properly test these systems during development, deployment and use. This paper presents early results from a work-in-progress academia-industry collaboration project and elaborates on the challenges...... of performing bit error rate testing at 100Gbps. In particular, we show how Bit Error Rate Testing (BERT) can be performed over an aggregated 100G Attachment Unit Interface (CAUI) by encapsulating the test data in Ethernet frames at line speed. Our results show that framed bit error rate testing can...
Random scattering of bits by prediction
Ratsaby, Joel
2009-01-01
We investigate a population of binary mistake sequences that result from learning with parametric models of different order. We obtain estimates of their error, algorithmic complexity and divergence from a purely random Bernoulli sequence. We study the relationship of these variables to the learner's information density parameter which is defined as the ratio between the lengths of the compressed to uncompressed files that contain the learner's decision rule. The results indicate that good learners have a low information density$\\rho$ while bad learners have a high $\\rho$. Bad learners generate atypically chaotic mistake sequences while good learners generate typically chaotic sequences that divide into two subgroups: the first consists of the typically stochastic sequences (with low divergence) which includes the sequences generated by the Bayes optimal predictor. The second subgroup consists of the atypically stochastic (but still typically chaotic) sequences that deviate from truly random Bernoulli sequenc...
Hanford coring bit temperature monitor development testing results report
Energy Technology Data Exchange (ETDEWEB)
Rey, D.
1995-05-01
Instrumentation which directly monitors the temperature of a coring bit used to retrieve core samples of high level nuclear waste stored in tanks at Hanford was developed at Sandia National Laboratories. Monitoring the temperature of the coring bit is desired to enhance the safety of the coring operations. A unique application of mature technologies was used to accomplish the measurement. This report documents the results of development testing performed at Sandia to assure the instrumentation will withstand the severe environments present in the waste tanks.
How to deal with malleability of BitCoin transactions
Andrychowicz, Marcin; Dziembowski, Stefan; Malinowski, Daniel; Mazurek, Łukasz
2013-01-01
BitCoin transactions are malleable in a sense that given a transaction an adversary can easily construct an equivalent transaction which has a different hash. This can pose a serious problem in some BitCoin distributed contracts in which changing a transaction's hash may result in the protocol disruption and a financial loss. The problem mostly concerns protocols, which use a "refund" transaction to withdraw a deposit in a case of the protocol interruption. In this short note, we show a gener...
Comparative Design of 16-Bit Sparse-Tree Rsfq Adder
S. Saddam Hussain; S. Mahaboob Basha
2014-01-01
In this paper, we propse 16-bit sparse tree RSFQ adder (Rapid single flux quantam), kogge-stone adder, carry lookahead adder. In general N-bit adders like Ripple carry adder s(slow adders compare to other adders), and carry lookahead adders(area consuming adders) are used in earlier days. But now the most of industries are using parallel prefix adders because of their advantages compare to kogge-stone adder, carry lookahead adder, Our prefix sparse tree adders are faster and ar...
An Efficient Power Optimized 1-bit CMOS Full Adder
Directory of Open Access Journals (Sweden)
R.M.Poojithaa
2013-06-01
Full Text Available Adders are the most important arithmetic units in a general microprocessor and the major source of power dissipation. Apart from addition, adders are also used in performing useful operations such as subtraction, multiplication, division and address calculation etc. In this paper, we have presented the study of different logic style using 1-bit full adder circuit and we have compared this 1-bit full adder on certain parameters such as power, number of transistor and frequency using microwind and T-spice.
BIT LENGTH REPLACEMENT STEGANOGRAPHY BASED ON DCT COEFFICIENTS
Directory of Open Access Journals (Sweden)
K B Shiva Kumar
2010-08-01
Full Text Available Steganography is a means of establishing secret communication through public channel in an artistic manner. In this paper, we propose Bit Length Replacement Steganography Based on DCT Coefficients (BLSDCT . The cover image is segmented into 8*8 blocks and DCT is applied on each block. The numbers of payload MSB bits are embedded into DCT coefficients of the cover image based on the values of DCT oefficients. It is observed that the proposed algorithm has better PSNR, Security and capacity compared to the existing algorithm.
Micro-electromechanical memory bit based on magnetic repulsion
López-Suárez, Miquel; Neri, Igor
2016-09-01
A bistable micro-mechanical system based on magnetic repulsion is presented exploring its applicability as memory unit where the state of the bit is encoded in the rest position of a deflected cantilever. The non-linearity induced on the cantilever can be tuned through the magnetic interaction intensity between the cantilever magnet and the counter magnet in terms of geometrical parameters. A simple model provides a sound prediction of the behavior of the system. Finally, we measured the energy required to store a bit of information on the system that, for the considered protocols, is bounded by the energy barrier separating the two stable states.
Comodulation masking release in bit-rate reduction systems
DEFF Research Database (Denmark)
Vestergaard, Martin D.; Rasmussen, Karsten Bo; Poulsen, Torben
1999-01-01
It has been suggested that the level dependence of the upper masking slopebe utilised in perceptual models in bit-rate reduction systems. However,comodulation masking release (CMR) phenomena lead to a reduction of themasking effect when a masker and a probe signal are amplitude modulated withthe...... same frequency. In bit-rate reduction systems the masker would be theaudio signal and the probe signal would represent the quantization noise.Masking curves have been determined for sinusoids and 1-Bark-wide noisemaskers in order to investigate the risk of CMR, when quantizing depths arefixed...
Perceptual importance analysis for H.264/AVC bit allocation
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The existing H.264/AVC rate control schemes rarely include the perceptual considerations. As a result, the improvements in visual quality are hardly comparable to those in peak signal-to-noise ratio (PSNR). In this paper, we propose a perceptual importance analysis scheme to accurately abstract the spatial and temporal perceptual characteristics of video contents. Then we perform bit allocation at macroblock (MB) level by adopting a perceptual mode decision scheme, which adaptively updates the Lagrangian multiplier for mode decision according to the perceptual importance of each MB. Simulation results show that the proposed scheme can efficiently reduce bit rates without visual quality degradation.
How to Convert a Flavor of Quantum Bit Commitment
DEFF Research Database (Denmark)
Crepeau, Claude; Legare, Frédéric; Salvail, Louis
2001-01-01
In this paper we show how to convert a statistically binding but computationally concealing quantum bit commitment scheme into a computationally binding but statistically concealing QBC scheme. For a security parameter n, the construction of the statistically concealing scheme requires O(n2......) executions of the statistically binding scheme. As a consequence, statistically concealing but computationally binding quantum bit commitments can be based upon any family of quantum one-way functions. Such a construction is not known to exist in the classical world....
An improved bit shuffling pixels-based image scrambling method
Institute of Scientific and Technical Information of China (English)
ZHAO Hong; WANG Hong-xia; WANG Jin
2011-01-01
@@ Compared with the Arnold transform, the image scrambling method based on bit shuffling pixels is much more secure, and has higher efficiency and speed.However, the key space of this bit shuffling pixels based method is too small to resist exhaustive search attack.Therefore, an improved method based on chaos is proposed in this paper.The security of the improved scheme is enhanced by increasing the number of the keys.Theoretical analysis and experimental results show that the proposed method is effective and has higher security.
Video coding bit allocation algorithm over wireless transmission channel
Institute of Scientific and Technical Information of China (English)
ZHANG Wei; ZHOU Yuan-hua
2006-01-01
For two-way video communications over wireless channels using the automatic repeat request (ARQ) retransmission scheme, TMN8 rate control scheme is not effective in minimizing the number of frames skipped and cannot guarantee video quality during the retransmissions of error packets. This paper presents a joint source channel bit allocation scheme that allocates target bits according to encoder buffer fullness and estimation of channel condition by retransmission information. The results obtained from implementing our scheme in H. 263 + coder over wireless channel model show that our proposed scheme encodes the video sequences with lower and steadier buffer delay, fewer frames skipped and higher average PSNR compared to TMN8.
Modeling of Bit Error Rate in Cascaded 2R Regenerators
DEFF Research Database (Denmark)
Öhman, Filip; Mørk, Jesper
2006-01-01
This paper presents a simple and efficient model for estimating the bit error rate in a cascade of optical 2R-regenerators. The model includes the influences of of amplifier noise, finite extinction ratio and nonlinear reshaping. The interplay between the different signal impairments and the rege......This paper presents a simple and efficient model for estimating the bit error rate in a cascade of optical 2R-regenerators. The model includes the influences of of amplifier noise, finite extinction ratio and nonlinear reshaping. The interplay between the different signal impairments...
Development of a jet-assisted polycrystalline diamond drill bit
Energy Technology Data Exchange (ETDEWEB)
Pixton, D.S.; Hall, D.R.; Summers, D.A.; Gertsch, R.E.
1997-12-31
A preliminary investigation has been conducted to evaluate the technical feasibility and potential economic benefits of a new type of drill bit. This bit transmits both rotary and percussive drilling forces to the rock face, and augments this cutting action with high-pressure mud jets. Both the percussive drilling forces and the mud jets are generated down-hole by a mud-actuated hammer. Initial laboratory studies show that rate of penetration increases on the order of a factor of two over unaugmented rotary and/or percussive drilling rates are possible with jet-assistance.
Techniques of Very Low Bit-Rate Speech Coding1
Institute of Scientific and Technical Information of China (English)
CUIHuijuan; TANGKun; ZHAOMing; ZHANGXin
2004-01-01
Techniques of very low bit-rate speech coding,such as lower than 800 bps are presented in this paper. The techniques of multi-frame, multi-sub-band, multimodel, and vector quantization etc. are effective to decrease the bit-rate of vocoders based on a linear prediction model. These techniques bring the vocoder not only high quality of the reconstructed speech, but also robustness.Vocoders which apply those techniques can synthesize clear and intelligent speech with some naturalness. The mean DRT (Diagnostic rhyme test) score of an 800 bps vocoder is 89.2% and 86.3% for a 600 bps vocoder.
Real-time minimal bit error probability decoding of convolutional codes
Lee, L. N.
1973-01-01
A recursive procedure is derived for decoding of rate R=1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e. fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications such as in the inner coding system for concatenated coding.
Real-time minimal-bit-error probability decoding of convolutional codes
Lee, L.-N.
1974-01-01
A recursive procedure is derived for decoding of rate R = 1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit, subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e., fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications, such as in the inner coding system for concatenated coding.
A minimum bit error-rate detector for amplify and forward relaying systems
Ahmed, Qasim Zeeshan
2012-05-01
In this paper, a new detector is being proposed for amplify-and-forward (AF) relaying system when communicating with the assistance of L number of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the system. The complexity of the system is further reduced by implementing this detector adaptively. The proposed detector is free from channel estimation. Our results demonstrate that the proposed detector is capable of achieving a gain of more than 1-dB at a BER of 10 -5 as compared to the conventional minimum mean square error detector when communicating over a correlated Rayleigh fading channel. © 2012 IEEE.
Single-Bit All Digital Frequency Synthesis Using Homodyne Sigma-Delta Modulation.
Sotiriadis, Paul
2016-10-05
All-digital frequency synthesis using band-pass sigma-delta modulation to achieve spectrally clean single-bit output is presented and mathematically analyzed resulting in a complete model to predict stability and output spectrum. The quadrature homodyne filter architecture is introduced resulting in efficient implementations of carrier-frequency centred bandpass filters for the modulator. A multiplier-less version of the quadrature homodyne filter architecture is also introduced to reduce complexity maintaining clean in-band spectrum. MATLAB and SIMULINK simulation results present the potential capabilities of the synthesizer architectures and validate the accuracy of the developed theoretical framework.
Linear-Time Non-Malleable Codes in the Bit-Wise Independent Tampering Model
DEFF Research Database (Denmark)
Cramer, Ronald; Damgård, Ivan Bjerre; Döttling, Nico
Non-malleable codes were introduced by Dziembowski et al. (ICS 2010) as coding schemes that protect a message against tampering attacks. Roughly speaking, a code is non-malleable if decoding an adversarially tampered encoding of a message m produces the original message m or a value m' (eventuall...... non-malleable codes of Agrawal et al. (TCC 2015) and of Cher- aghchi and Guruswami (TCC 2014) and improves the previous result in the bit-wise tampering model: it builds the first non-malleable codes with linear-time complexity and optimal-rate (i.e. rate 1 - o(1))....
A 1.5 bit/s Pipelined Analog-to-Digital Converter Design with Independency of Capacitor Mismatch
Institute of Scientific and Technical Information of China (English)
LI Dan; RONG Men-tian; MAO Jun-fa
2007-01-01
A new technique which is named charge temporary storage technique (CTST) was presented to improve the linearity of a 1.5 bit/s pipelined analog-to-digital converter (ADC).The residual voltage was obtained from the sampling capacitor, and the other capacitor was just a temporary storage of charge.Then, the linearity produced by the mismatch of these capacitors was eliminated without adding extra capacitor error-averaging amplifiers.The simulation results confirmed the high linearity and low dissipation of pipelined ADCs implemented in CTST, so CTST was a new method to implement high resolution, small size ADCs.
Gravitational Couplings for Gop-Planes and y-Op-Planes
Ospina-Giraldo, J F
2000-01-01
The Wess-Zumino actions for generalized orientifold planes (GOp-planes) and y-deformed orientifold planes (yOp-planes) are presented and two series power expantions are realized from whiches processes that involves GOp-planes,yOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard GOp-planes and y-Op-planes are showed.
How to Convert a Flavor of Quantum Bit Commitment
DEFF Research Database (Denmark)
Crepeau, Claude; Legare, Frédéric; Salvail, Louis
2001-01-01
In this paper we show how to convert a statistically binding but computationally concealing quantum bit commitment scheme into a computationally binding but statistically concealing QBC scheme. For a security parameter n, the construction of the statistically concealing scheme requires O(n2) exec...
KEAMANAN CITRA DENGAN WATERMARKING MENGGUNAKAN PENGEMBANGAN ALGORITMA LEAST SIGNIFICANT BIT
Directory of Open Access Journals (Sweden)
Kurniawan Kurniawan
2015-01-01
Full Text Available Image security is a process to save digital. One method of securing image digital is watermarking using Least Significant Bit algorithm. Main concept of image security using LSB algorithm is to replace bit value of image at specific location so that created pattern. The pattern result of replacing the bit value of image is called by watermark. Giving watermark at image digital using LSB algorithm has simple concept so that the information which is embedded will lost easily when attacked such as noise attack or compression. So need modification like development of LSB algorithm. This is done to decrease distortion of watermark information against those attacks. In this research is divided by 6 process which are color extraction of cover image, busy area search, watermark embed, count the accuracy of watermark embed, watermark extraction, and count the accuracy of watermark extraction. Color extraction of cover image is process to get blue color component from cover image. Watermark information will embed at busy area by search the area which has the greatest number of unsure from cover image. Then watermark image is embedded into cover image so that produce watermarked image using some development of LSB algorithm and search the accuracy by count the Peak Signal to Noise Ratio value. Before the watermarked image is extracted, need to test by giving noise and doing compression into jpg format. The accuracy of extraction result is searched by count the Bit Error Rate value.
Optimization Approaches for Designing a Novel 4-Bit Reversible Comparator
Zhou, Ri-gui; Zhang, Man-qun; Wu, Qian; Li, Yan-cheng
2013-02-01
Reversible logic is a new rapidly developed research field in recent years, which has been receiving much attention for calculating with minimizing the energy consumption. This paper constructs a 4×4 new reversible gate called ZRQ gate to build quantum adder and subtraction. Meanwhile, a novel 1-bit reversible comparator by using the proposed ZRQC module on the basis of ZRQ gate is proposed as the minimum number of reversible gates and quantum costs. In addition, this paper presents a novel 4-bit reversible comparator based on the 1-bit reversible comparator. One of the vital important for optimizing reversible logic is to design reversible logic circuits with the minimum number of parameters. The proposed reversible comparators in this paper can obtain superiority in terms of the number of reversible gates, input constants, garbage outputs, unit delays and quantum costs compared with the existed circuits. Finally, MATLAB simulation software is used to test and verify the correctness of the proposed 4-bit reversible comparator.
Forecasting the life of rock-bit journal bearings
Energy Technology Data Exchange (ETDEWEB)
Kelly, J.L. (Hughes Tool Co. (US))
1990-06-01
This paper describes an analytical procedure for forecasting the life expectancy of rock-bit journal bearings. Actual performance data and reliability analyses are used to establish empirical relationships and a graphic procedure that relates the risk of bearing failure to operating parameters and drilling cost.
Advanced "Dagang" Screw Drill and Man-made Diamond Bit
Institute of Scientific and Technical Information of China (English)
Wu Zhenya
1995-01-01
@@ Central Machinery Plant, a state enterprise, is a comprehensive petroleum machinery enterprise mainly manufacturing petroleum machinery equipment and drilling & production fillings, also maintaining oilfield construction equipment and submersible electrical pumps. In 1992,the plant was appointed to manufacture positive displacement drill, reciprocating pump, man-made diamond bit, downhole tool and roller precision chain, and to maintain submersible electrical pumps by CNPC.
An Educator’s Guide to Bits, Bytes, and Teaching
Amitabh Vikram Dwivedi
2016-01-01
Book review of: “Technology for Classroom and Online Learning: An Educator’s Guide to Bits, Bytes, and Teaching.” By Samuel M. Kwon, Daniel R. Tomal, and Aram S. Agajanian. Lanham, MD: Rowman and Littlefield, 2016. ISBN 978-1-4758-1544-3
An Educator’s Guide to Bits, Bytes, and Teaching
Directory of Open Access Journals (Sweden)
Amitabh Vikram Dwivedi
2016-11-01
Full Text Available Book review of: “Technology for Classroom and Online Learning: An Educator’s Guide to Bits, Bytes, and Teaching.” By Samuel M. Kwon, Daniel R. Tomal, and Aram S. Agajanian. Lanham, MD: Rowman and Littlefield, 2016. ISBN 978-1-4758-1544-3
"Material interactions": from atoms & bits to entangled practices
DEFF Research Database (Denmark)
Vallgårda, Anna
and intellectually stimulating panel moderated by Prof. Mikael Wiberg consisting of a number of scholars with a well-developed view on digital materialities to fuel a discussion on material interactions - from atoms & bits to entangled practices. These scholars include: Prof. Hiroshi Ishii, Prof. Paul Dourish...
Different Mass Processing Services in a Bit Repository
DEFF Research Database (Denmark)
Jurik, Bolette; Zierau, Eld
2011-01-01
This paper investigates how a general bit repository mass processing service using different programming models and platforms can be specified. Such a service is needed in large data archives, especially libraries, where different ways of doing mass processing is needed for different digital libr...
Quantum measurement and entanglement of spin quantum bits in diamond
Pfaff, W.
2013-01-01
This thesis presents a set of experiments that explore the possible realisation of a macroscopic quantum network based on solid-state quantum bits. Such a quantum network would allow for studying quantum mechanics on large scales (meters, or even kilometers), and can open new possibilities for
Pinning of written bits in perpendicular recording media
Energy Technology Data Exchange (ETDEWEB)
Greaves, S.J.; Muraoka, H. E-mail: muraoka@riec.tohoku.ac.jp; Sonobe, Y.; Schabes, M.; Nakamura, Y
2001-10-01
A perpendicular medium comprising two distinct magnetic layers is described. One layer has a granular structure with isolated, exchange-decoupled grains and the other is a continuous, exchange-coupled layer. In the combined structure domain wall movement is restricted and reversed grains within written bits are eliminated. The S/N ratio is improved compared with single layers of either type alone.
Low bit rate near-transparent image coding
Zhu, Bin; Tewfik, Ahmed H.; Gerek, Oemer N.
1995-04-01
In this paper, we describe an improved version of our previous approach for low bit rate near- perceptually transparent image compression. The method exploits both frequency and spatial domain visual masking effects and uses a combination of Fourier and wavelet representations to encode different bands. The frequency domain masking model is based on the psychophysical masking experimental data of sinusoidal patterns while the spatial domain masking is computed with a modified version of Girod's model. A discrete cosine transform is used in conjunction with frequency domain masking to encode the low frequency subimages. The medium and high frequency subimages are encoded in the wavelet domain with spatial domain masking. The main improvement over our previous technique is that a better model is used to calculate the tolerable error level for the subimages in the wavelet domain, and a boundary control is used to prevent or reduce the ringing noise in the decoded image. This greatly improves the decoded image quality for the same coding bit rates. Experiments show the approach can achieve very high quality to nearly transparent compression at bit rates of 0.2 to 0.4 bits/pixel for the image Lena.
Quantum measurement and entanglement of spin quantum bits in diamond
Pfaff, W.
2013-01-01
This thesis presents a set of experiments that explore the possible realisation of a macroscopic quantum network based on solid-state quantum bits. Such a quantum network would allow for studying quantum mechanics on large scales (meters, or even kilometers), and can open new possibilities for appli
Evolutes of Hyperbolic Plane Curves
Institute of Scientific and Technical Information of China (English)
Shyuichi IZUMIYA; Dong He PEI; Takashi SANO; Erika TORII
2004-01-01
We define the notion of evolutes of curves in a hyperbolic plane and establish the relationships between singularities of these subjects and geometric invariants of curves under the action of the Lorentz group. We also describe how we can draw the picture of an evolute of a hyperbolic plane curve in the Poincar(e) disk.
Conceptual Design of Wave Plane
DEFF Research Database (Denmark)
Frigaard, Peter; Trewers, Andrew; Kofoed, Jens Peter;
The Wave Plane is a patented Wave Energy device of the overtopping type, designed to capture potential as well as kinetic energy. This is as such different to other overtopping devices, who usually only focus on potential energy. If Wave Plane A/S can deliver the turbine technology to utilize both...
Analysis of bit-rock interaction during stick-slip vibrations using PDC cutting force model
Energy Technology Data Exchange (ETDEWEB)
Patil, P.A.; Teodoriu, C. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE
2013-08-01
Drillstring vibration is one of the limiting factors maximizing the drilling performance and also causes premature failure of drillstring components. Polycrystalline diamond compact (PDC) bit enhances the overall drilling performance giving the best rate of penetrations with less cost per foot but the PDC bits are more susceptible to the stick slip phenomena which results in high fluctuations of bit rotational speed. Based on the torsional drillstring model developed using Matlab/Simulink for analyzing the parametric influence on stick-slip vibrations due to drilling parameters and drillstring properties, the study of relations between weight on bit, torque on bit, bit speed, rate of penetration and friction coefficient have been analyzed. While drilling with the PDC bits, the bit-rock interaction has been characterized by cutting forces and the frictional forces. The torque on bit and the weight on bit have both the cutting component and the frictional component when resolved in horizontal and vertical direction. The paper considers that the bit is undergoing stick-slip vibrations while analyzing the bit-rock interaction of the PDC bit. The Matlab/Simulink bit-rock interaction model has been developed which gives the average cutting torque, T{sub c}, and friction torque, T{sub f}, values on cutters as well as corresponding average weight transferred by the cutting face, W{sub c}, and the wear flat face, W{sub f}, of the cutters value due to friction.
Experimental study of rock-breaking with an offset single cone bit
Institute of Scientific and Technical Information of China (English)
Chen Yinghua
2008-01-01
An experimental study of rock-breaking with an offset single cone bit was completed on the bit bench test equipment.Data such as transmission ratio,weight on bit (WOB),rate of penetration (ROP)and torque on bit were acquired in the experiments.Based on analyzing the experimental results,several conclusions were drawn as follows.The transmission ratio of the offset single-cone bit changed slightly with rotary speed of bit,weight on bit and offset distance.The rate of penetration of the offset singlecone bit increased with increase of WOB and offset distance.The torque on bit increased with increase of offset distance under the same WOB and bit rotary speed,decreased with increase of bit rotary speed under the same WOB.The rock-breaking mechanism of the offset single-cone bit was a scraping action.This indicates that the offset single-cone bit is a chipping type bit.
Estimating Hardness from the USDC Tool-Bit Temperature Rise
Bar-Cohen, Yoseph; Sherrit, Stewart
2008-01-01
A method of real-time quantification of the hardness of a rock or similar material involves measurement of the temperature, as a function of time, of the tool bit of an ultrasonic/sonic drill corer (USDC) that is being used to drill into the material. The method is based on the idea that, other things being about equal, the rate of rise of temperature and the maximum temperature reached during drilling increase with the hardness of the drilled material. In this method, the temperature is measured by means of a thermocouple embedded in the USDC tool bit near the drilling tip. The hardness of the drilled material can then be determined through correlation of the temperature-rise-versus-time data with time-dependent temperature rises determined in finite-element simulations of, and/or experiments on, drilling at various known rates of advance or known power levels through materials of known hardness. The figure presents an example of empirical temperature-versus-time data for a particular 3.6-mm USDC bit, driven at an average power somewhat below 40 W, drilling through materials of various hardness levels. The temperature readings from within a USDC tool bit can also be used for purposes other than estimating the hardness of the drilled material. For example, they can be especially useful as feedback to control the driving power to prevent thermal damage to the drilled material, the drill bit, or both. In the case of drilling through ice, the temperature readings could be used as a guide to maintaining sufficient drive power to prevent jamming of the drill by preventing refreezing of melted ice in contact with the drill.
Out-of-plane magnetized cone-shaped magnetic nanoshells
Ball, D. K.; Günther, S.; Fritzsche, M.; Lenz, K.; Varvaro, G.; Laureti, S.; Makarov, D.; Mücklich, A.; Facsko, S.; Albrecht, M.; Fassbender, J.
2017-03-01
The geometry of a magnetic nano-object, namely its shape and dimensions determines the complex electromagnetic responses. Here, we address the geometry-induced changes of the magnetic properties of thin ferromagnetic Co/Pd multilayers with out-of-plane magnetic anisotropy deposited on three-dimensionally curved templates. For this purpose, arrays of self-assembled cone-shaped nano-objects with a chracteristic size of either 30 or 70 nm were created in GaSb(0 0 1) by the ion erosion technique. The templates are designed in the way that the shape of the cone remains the same for all the samples; namely, we keep the opening angle at about 55° by adjusting the ratio between the cone height and its base diameter to be about 1. In this case, we are able to address the impact of the linear dimensions of the object on the magnetic properties and exclude the impact of the shape from the consideration. The deposition of 15 nm thick Co/Pd multilayers on top of the cone templates results in the formation of a close-packed array of 2D magnetic cone-shaped shells. Integral angle-dependent magnetometry measurements demonstrate that the local curvature results in the spread of the easy axes of magnetization following the shape of the nanocones independent of the linear dimensions of the cones. At the same time different local magnetic domain patterns are observed for samples prepared on 30 and 70 nm large cones. When the thickness of the magnetic shell is only half of the linear dimension of a cone, a clear multidomain state is observed. Remarkably, we find that the neighboring magnetic cone-shaped shells are exchange decoupled when the linear dimension of a cone is four times larger compared to the thickness of the magnetic shell. These findings are relevant for the further development of tilted bit patterned magnetic recording media as well as for the emergent field of magnetism in curved geometries.
Louvel, Guillaume; Der Sarkissian, Clio; Hanghøj, Kristian; Orlando, Ludovic
2016-11-01
Micro-organisms account for most of the Earth's biodiversity and yet remain largely unknown. The complexity and diversity of microbial communities present in clinical and environmental samples can now be robustly investigated in record times and prices thanks to recent advances in high-throughput DNA sequencing (HTS). Here, we develop metaBIT, an open-source computational pipeline automatizing routine microbial profiling of shotgun HTS data. Customizable by the user at different stringency levels, it performs robust taxonomy-based assignment and relative abundance calculation of microbial taxa, as well as cross-sample statistical analyses of microbial diversity distributions. We demonstrate the versatility of metaBIT within a range of published HTS data sets sampled from the environment (soil and seawater) and the human body (skin and gut), but also from archaeological specimens. We present the diversity of outputs provided by the pipeline for the visualization of microbial profiles (barplots, heatmaps) and for their characterization and comparison (diversity indices, hierarchical clustering and principal coordinates analyses). We show that metaBIT allows an automatic, fast and user-friendly profiling of the microbial DNA present in HTS shotgun data sets. The applications of metaBIT are vast, from monitoring of laboratory errors and contaminations, to the reconstruction of past and present microbiota, and the detection of candidate species, including pathogens.
Crisis bifurcations in plane Poiseuille flow
Zammert, Stefan
2015-01-01
Direct numerical simulations of transitional plane Poiseuille flow in a mirror-symmetric subspace reveal several interior and exterior crisis bifurcations. They appear in the upper branch that emerges in a saddle-node bifurcation near $Re_{SN}=641$ and then undergoes several bifurcations into a chaotic attractor. Near $Re_{XC}=785.95$ the attractor collides with the lower-branch state and turns into a chaotic saddle in a exterior crisis, with a characteristic $(Re-Re_{XC})^{-\\delta}$ variation in lifetimes. For intermediate Reynolds numbers, the attractor undergoes several interior crises, in which new states appear and intermittent behavior can be observed. They contribute to increasing the complexity of the dynamics and to a more dense coverage of state space. The exterior crisis marks the onset of transient turbulence in this subspace of plane Poiseuille flow.
Space-bounded communication complexity
DEFF Research Database (Denmark)
Brody, Joshua Eric; Chen, Shiteng; Papakonstantinou, Periklis A.
2013-01-01
In the past thirty years, Communication Complexity has emerged as a foundational tool to proving lower bounds in many areas of computer science. Its power comes from its generality, but this generality comes at a price---no superlinear communication lower bound is possible, since a player may...... communicate his entire input. However, what if the players are limited in their ability to recall parts of their interaction? We introduce memory models for 2-party communication complexity. Our general model is as follows: two computationally unrestricted players, Alice and Bob, each have s(n) bits of memory....... When a player receives a bit of communication, he "compresses" his state. This compression may be an arbitrary function of his current memory contents, his input, and the bit of communication just received; the only restriction is that the compression must return at most s(n) bits. We obtain memory...
Modular trigger processing The GCT muon and quiet bit system
Stettler, Matthew; Hansen, Magnus; Iles, Gregory; Jones, John; PH-EP
2007-01-01
The CMS Global Calorimeter Trigger system's HCAL Muon and Quiet bit reformatting function is being implemented with a novel processing architecture. This architecture utilizes micro TCA, a modern modular communications standard based on high speed serial links, to implement a processing matrix. This matrix is configurable in both logical functionality and data flow, allowing far greater flexibility than current trigger processing systems. In addition, the modular nature of this architecture allows flexibility in scale unmatched by traditional approaches. The Muon and Quiet bit system consists of two major components, a custom micro TCA backplane and processing module. These components are based on Xilinx Virtex5 and Mindspeed crosspoint switch devices, bringing together state of the art FPGA based processing and Telcom switching technologies.
Implementation of Variable Least Significant Bits Stegnographyusing DDDB Algorithm
Directory of Open Access Journals (Sweden)
Sahib Khan
2011-11-01
Full Text Available Nobody can deny the importance of secure communication.Different techniques are being utilized to achieve this task. Image Stegnography is one such method in which we hide data in an otherwise ordinary image. In this paper, a novel Stegnographic technique named as Variable Least Significant Bits Stegnography (VLSB is proposed. To implement VLSB, we designed an algorithm named as Decreasing Distance Decreasing Bits Algorithm (DDDBA. In each test we performed, the data hiding capacity was always greater than 50 % ( a barrier considered in image Stegnography, ranging up to 69 % with signal to noise ratio varying from 10 db to 5 db respectively. The DDDBA provides self encryption mechanism in VLSB Stegnography, making the Steganalysis more difficult.
Efficient biased random bit generation for parallel processing
Energy Technology Data Exchange (ETDEWEB)
Slone, D.M.
1994-09-28
A lattice gas automaton was implemented on a massively parallel machine (the BBN TC2000) and a vector supercomputer (the CRAY C90). The automaton models Burgers equation {rho}t + {rho}{rho}{sub x} = {nu}{rho}{sub xx} in 1 dimension. The lattice gas evolves by advecting and colliding pseudo-particles on a 1-dimensional, periodic grid. The specific rules for colliding particles are stochastic in nature and require the generation of many billions of random numbers to create the random bits necessary for the lattice gas. The goal of the thesis was to speed up the process of generating the random bits and thereby lessen the computational bottleneck of the automaton.
MIMO ARQ with Multi-bit Feedback: Outage Analysis
Nguyen, Khoa D; Fabregas, Albert Guillen i; Letzepis, Nick
2010-01-01
We study the asymptotic outage performance of incremental redundancy automatic repeat request (INR-ARQ) transmission over the multiple-input multiple-output (MIMO) block-fading channels with discrete input constellations. We first show that transmission with random codes using a discrete signal constellation across all transmit antennas achieves the optimal outage diversity given by the Singleton bound. We then analyze the optimal SNR-exponent and outage diversity of INR-ARQ transmission over the MIMO block-fading channel. We show that a significant gain in outage diversity is obtained by providing more than one bit feedback at each ARQ round. Thus, the outage performance of INR-ARQ transmission can be remarkably improved with minimal additional overhead. A suboptimal feedback and power adaptation rule, which achieves the optimal outage diversity, is proposed for MIMO INR-ARQ, demonstrating the benefits provided by multi-bit feedback.
A novel chaotic encryption scheme based on pseudorandom bit padding
Sadra, Yaser; Fard, Zahra Arasteh
2012-01-01
Cryptography is always very important in data origin authentications, entity authentication, data integrity and confidentiality. In recent years, a variety of chaotic cryptographic schemes have been proposed. These schemes has typical structure which performed the permutation and the diffusion stages, alternatively. The random number generators are intransitive in cryptographic schemes and be used in the diffusion functions of the image encryption for diffused pixels of plain image. In this paper, we propose a chaotic encryption scheme based on pseudorandom bit padding that the bits be generated by a novel logistic pseudorandom image algorithm. To evaluate the security of the cipher image of this scheme, the key space analysis, the correlation of two adjacent pixels and differential attack were performed. This scheme tries to improve the problem of failure of encryption such as small key space and level of security.
Statistical mechanics analysis of thresholding 1-bit compressed sensing
Xu, Yingying
2016-01-01
The one-bit compressed sensing framework aims to reconstruct a sparse signal by only using the sign information of its linear measurements. To compensate for the loss of scale information, past studies in the area have proposed recovering the signal by imposing an additional constraint on the L2-norm of the signal. Recently, an alternative strategy that captures scale information by introducing a threshold parameter to the quantization process was advanced. In this paper, we analyze the typical behavior of the thresholding 1-bit compressed sensing utilizing the replica method of statistical mechanics, so as to gain an insight for properly setting the threshold value. Our result shows that, fixing the threshold at a constant value yields better performance than varying it randomly when the constant is optimally tuned, statistically. Unfortunately, the optimal threshold value depends on the statistical properties of the target signal, which may not be known in advance. In order to handle this inconvenience, we ...
b.i.t. Bremerhaven: Thin Clients entlasten Schulen
Das Schulamt Bremerhaven zentralisiert die Verwaltungs-IT und schafft dadurch Freiräume für pädagogische und organisatorische Herausforderungen. Pflege und Support der neuen Infrastruktur übernimmt der Dienstleister b.i.t. Bremerhaven, die Thin Clients kommen vom Bremer Hersteller IGEL Technology. Ganztagsschulen, das 12-jährige Abitur, PISA, der Wegfall der Orientierungsstufe - deutsche Schulen müssen derzeit zahlreiche organisatorische und pädagogische Herausforderungen bewältigen. Um die neuen Strukturen umsetzen zu können, werden zusätzliche Ressourcen benötigt. Das Schulamt Bremerhaven hat gemeinsam mit dem Dienstleister b.i.t. Bremerhaven (Betrieb für Informationstechnologie) eine intelligente Lösung gefunden, wie sich die benötigten finanziellen Freiräume schaffen lassen.
Opportunistic Collaborative Beamforming with One-Bit Feedback
Pun, Man-On; Poor, H Vincent
2008-01-01
An energy-efficient opportunistic collaborative beamformer with one-bit feedback is proposed for ad hoc sensor networks over Rayleigh fading channels. In contrast to conventional collaborative beamforming schemes in which each source node uses channel state information to correct its local carrier offset and channel phase, the proposed beamforming scheme opportunistically selects a subset of source nodes whose received signals combine in a quasi-coherent manner at the intended receiver. No local phase-precompensation is performed by the nodes in the opportunistic collaborative beamformer. As a result, each node requires only one-bit of feedback from the destination in order to determine if it should or shouldn't participate in the collaborative beamformer. Theoretical analysis shows that the received signal power obtained with the proposed beamforming scheme scales linearly with the number of available source nodes. Since the the optimal node selection rule requires an exhaustive search over all possible subs...
Quantum communication based on orthogonal states enables quantum bit commitment
He, Guang Ping
2011-01-01
For more than a decade, it was believed that unconditionally secure quantum bit commitment (QBC) is impossible. But basing on a formerly proposed quantum communication scheme using orthogonal states, here we build a QBC protocol in which the density matrices of the quantum states encoding the commitment do not satisfy a crucial condition on which the impossibility proofs of QBC are based. Thus unconditional security can be achieved. Our protocol is very feasible with currently available technology. It re-opens the venue for other "post-cold-war" multi-party cryptographic protocols, e.g., unconditionally secure quantum bit string commitment and quantum strong coin tossing with an arbitrarily small bias. This result also has a strong influence on the Clifton-Bub-Halvorson theorem which suggests that quantum theory could be characterized in terms of information-theoretic constraints.
An Improved Rate Matching Method for DVB Systems Through Pilot Bit Insertion
Directory of Open Access Journals (Sweden)
Seyed Mohammad-Sajad Sadough
2012-09-01
Full Text Available Classically, obtaining different coding rates in turbo codes is achieved through the well known puncturing procedure. However, puncturing is a critical procedure since the way the encoded sequence is punctured influences directly the decoding performance. In this work, we propose to mix the data sequence at the turbo encoder input inside the Digital Video Broadcasting (DVB standard with some pilot (perfectly known bits. By using variable pilot insertion rates, we achieve different coding rates with more flexibility. The proposed scheme is able to use a less complex mother code compared to that used in a conventional punctured turbo code. We also analyze the effect of different type of pilot insertion such as random and periodic schemes. Simulation results provided in the context of DVB show that in addition to providing flexible encoder design and reducing the encoder complexity, pilot insertion can improve slightly the performance of turbo decoders, compared to a conventional punctured turbo code.
Small digital recording head has parallel bit channels, minimizes cross talk
Eller, E. E.; Laue, E. G.
1964-01-01
A small digital recording head consists of closely spaced parallel wires, imbedded in a ferrite block to concentrate the magnetic flux. Parallel-recorded information bits are converted into serial bits on moving magnetic tape and cross talk is suppressed.
Secure and Efficient Pseudorandom Bit Generator for Chaotic Stream Ciphers
Institute of Scientific and Technical Information of China (English)
WANG Xiao-Min; ZHANG Jia-Shu
2007-01-01
Based on the entropy criterion and n-dimensional uniform distribution of nonlinear digital filter (NDF), we present an efficient NDF-based pseudorandom bit generator (NDF-PRBG) for chaotic stream ciphers. The cryptographic properties of the proposed NDF-PRBG are analysed, and some experiments are made. The results show that it has desirable cryptographic properties, and can be used to construct secure stream ciphers with high speed.
Ballistic bit addressing in a magnetic memory cell array
Schumacher, H. W.
2005-01-01
A ringing free bit addressing scheme for magnetic memories like MRAM (magnetic random access memory) is proposed. As in standard MRAM addressing schemes the switching of a selected cell is obtained by the combination of two half-select field pulses. Numerical solutions of a single spin model of an MRAM cell show that the pulse parameters can be chosen such that the application of the half select pulse induces a full precessional turn of the magnetization (no switch) whereas the superposition ...
Institute of Scientific and Technical Information of China (English)
胡纲
2006-01-01
微软终于在德国汉诺威举行的CeBIT 2006科技展示上揭开了所谓Origami项目的神秘面纱：原来这是一种使用Windows XP Tablet操作系统，具有触摸屏和无线连接的超便携PC （UltraMobile PC,简称UMPC）。
Amorphous Silicon 16—bit Array Photodetector①
Institute of Scientific and Technical Information of China (English)
ZHANGShaoqiang; XUZhongyang; 等
1997-01-01
An amorphous silicon 16-bit array photodetector with the a-SiC/a-Si heterojunction diode is presented.The fabrication processes of the device were studied systematically.By the optimum of the diode structure and the preparation procedures,the diode with Id<10-12A/mm2 and photocurrentIp≥0.35A/W has been obtained at the wavelength of 632nm.
Secure Classical Bit Commitment using Fixed Capacity Communication Channels
Kent, Adrian
1999-01-01
If mutually mistrustful parties A and B control two or more appropriately located sites, special relativity can be used to guarantee that a pair of messages exchanged by A and B are independent. In earlier work, we used this fact to define a relativistic bit commitment protocol, RBC1, in which security is maintained by exchanging a sequence of messages whose transmission rate increases exponentially in time. We define here a new relativistic protocol, RBC2, which requires only a constant tran...
Generating bit reversed numbers for calculating fast fourier transform
Digital Repository Service at National Institute of Oceanography (India)
Suresh, T.
(6) x (7)). Calculation of FFT becomes a difficult task for computation with input data in natural order and without reordering. Thus an efficient method of reordering is required for FFT calculation. We review a few methods of generating bit... with each successive stage. Other algorithms that depend on the efficient use of swapping data from an array are given in Buneman (1986) Evans (1987) and Walker (1990). Swapping of data is the most widely used method for reordering in FFT calculation. A...
Delay Efficient 32-Bit Carry-Skip Adder
Yu Shen Lin; Damu Radhakrishnan
2008-01-01
The design of a 32-bit carry-skip adder to achieve minimum delay is presented in this paper. A fast carry look-ahead logic using group generate and group propagate functions is used to speed up the performance of multiple stages of ripple carry adders. The group generate and group propagate functions are generated in parallel with the carry generation for each block. The optimum block sizes are decided by considering the critical path into account. The new architecture ...
A 64 Bits Rotor Enhanced Block Cipher (Rebc3
Directory of Open Access Journals (Sweden)
Ahmed ElShafee
2013-04-01
Full Text Available This paper gives a new proposed cryptosystem (REBC3 that is designed to take advantages of the new generation of 64bits microprocessors which commercially known as x64 systems. The old version REBC2,which was published in Africon 2007. REBC2 was basically developed for the 32bits microprocessors which is commercially known as x86 systems. REBC3 like REBC2 use the concept of rotor enhanced blockcipher which was initially proposed by the author in [NRSC 2002] on the first version of REBC. REBC2 used the same concept from a another point of view, which is using rotors to achieve two basiccryptographic operations; permutation, and substitution. Round key is generated using rotor too, which is used to achieve ciphertext key dependency. To enhance non-linearity and to resist linear cryptanalysis,REBC3 has a variable block, and key lengths. Each round has its own block length which depends on round the key and round key length. Dependency is based upon the previous round generated key. Rotors implemented using successive affine transformation . The 32 bits version was proposed in KAMFEE cipher, then the 64bits version was proposed in KAMFEE-X64 cipher. This achieved memory-less, normalized ciphertext statistics, and small processing speed trend. The strength of this system is compared with the REBC2 and RIJNDAEL (AES ciphers.REBC3 cipher gives excellent results from security characteristics and statistical point of view of. So authors suggests to use REBC3 in the area of banking and electronic fund transfer.
CMOS Bit-Stream Band-Pass Beamforming
2016-03-31
the Antenna Inputs,” IEEE Journal of Solid-State Circuits, Jun., 2014. 4. H. Aliakbarian, et al., “Analogue versus Digital for Baseband Beam...Arbor, Michigan, USA, 48109 Abstract: We introduce a unique bandpass ΣΔ based common module with reconfigurable, bit-stream based digital beam...forming (DBF). An array of bandpass ΣΔ modulators accurately and efficiently digitizes the IF signals. Beam-forming is implemented directly through
Development of Deduced Protein Database Using Variable Bit Binary Encoding
Directory of Open Access Journals (Sweden)
B. Parvathavarthini
2008-01-01
Full Text Available A large amount of biological data is semi-structured and stored in any one the following file formats such as flat, XML and relational files. These databases must be integrated with the structured data available in relational or object-oriented databases. The sequence matching process is difficult in such file format, because string comparison takes more computation cost and time. To reduce the memory storage size of amino acid sequence in protein database, a novel probability-based variable bit length encoding technique has been introduced. The number of mapping of triplet CODON for every amino acid evaluates the probability value. Then, a binary tree has been constructed to assign unique bits of binary codes to each amino acid. This derived unique bit pattern of amino acid replaces the existing fixed byte representation. The proof of reduced protein database space has been discussed and it is found to be reduced between 42.86 to 87.17%. To validate our method, we have collected few amino acid sequences of major organisms like Sheep, Lambda phage and etc from NCBI and represented them using proposed method. The comparison shows that of minimum and maximum reduction in storage space are 43.30% and 72.86% respectively. In future the biological data can further be reduced by applying lossless compression on this deduced data.
Low Power 256-bit Modified Carry Select Adder
Directory of Open Access Journals (Sweden)
P. Ramani
2014-09-01
Full Text Available Carry Select Adder (CSLA is one of the high speed adders used in many computational systems to perform fast arithmetic operations. When compared to earlier Ripple Carry Adder and Carry Look Ahead Adder, Regular CSLA (R-CSLA is observed to provide optimized results in terms of area. This study proposes an efficient method which replaces the RCA using BEC. The modified CSLA architecture has been developed using gate-level modification to significantly reduce the delay and power of the CSLA. Based on this modification 8-, 16-, 32-, 64- and 128-bit Square-Root CSLA (SQRT CSLA architecture have been developed and compared with the regular SQRT CSLA architecture. The proposed design for 256-bit has reduced power and delay as compared with the regular SQRT CSLA. Designs were developed using structural Verilog module and synthesized using Xilinx ISE simulator and the implementation is done in cadence RTL compiler using 0.18 µm technology. For 256-bit addition in this study, it is proposed to simple gate level modification which significantly reduces the power by 19.4% when compared with R-CSLA. The result analysis shows that the proposed architecture achieves two folded advantages in terms of delay and power.
On the Lorentz invariance of bit-string geometry
Energy Technology Data Exchange (ETDEWEB)
Noyes, H.P.
1995-09-01
We construct the class of integer-sided triangles and tetrahedra that respectively correspond to two or three discriminately independent bit-strings. In order to specify integer coordinates in this space, we take one vertex of a regular tetrahedron whose common edge length is an even integer as the origin of a line of integer length to the {open_quotes}point{close_quotes} and three integer distances to this {open_quotes}point{close_quotes} from the three remaining vertices of the reference tetrahedron. This - usually chiral - integer coordinate description of bit-string geometry is possible because three discriminately independent bit-strings generate four more; the Hamming measures of these seven strings always allow this geometrical interpretation. On another occasion we intend to prove the rotational invariance of this coordinate description. By identifying the corners of these figures with the positions of recording counters whose clocks are synchronized using the Einstein convention, we define velocities in this space. This suggests that it may be possible to define boosts and discrete Lorentz transformations in a space of integer coordinates. We relate this description to our previous work on measurement accuracy and the discrete ordered calculus of Etter and Kauffman (DOC).
Biometric Quantization through Detection Rate Optimized Bit Allocation
Chen, C.; Veldhuis, R. N. J.; Kevenaar, T. A. M.; Akkermans, A. H. M.
2009-12-01
Extracting binary strings from real-valued biometric templates is a fundamental step in many biometric template protection systems, such as fuzzy commitment, fuzzy extractor, secure sketch, and helper data systems. Previous work has been focusing on the design of optimal quantization and coding for each single feature component, yet the binary string—concatenation of all coded feature components—is not optimal. In this paper, we present a detection rate optimized bit allocation (DROBA) principle, which assigns more bits to discriminative features and fewer bits to nondiscriminative features. We further propose a dynamic programming (DP) approach and a greedy search (GS) approach to achieve DROBA. Experiments of DROBA on the FVC2000 fingerprint database and the FRGC face database show good performances. As a universal method, DROBA is applicable to arbitrary biometric modalities, such as fingerprint texture, iris, signature, and face. DROBA will bring significant benefits not only to the template protection systems but also to the systems with fast matching requirements or constrained storage capability.
Tit-Bits, New Journalism, and early Sherlock Holmes fandom
Directory of Open Access Journals (Sweden)
Ann K. McClellan
2017-03-01
Full Text Available The Strand's more popular sister magazine, Tit-Bits, played a significant role in establishing Sherlock Holmes as a literary and cultural icon, particularly through its use of participatory practices, cross-promotion, and transmedia storytelling. I argue that Tit-Bits' late 19th-century New Journalism techniques like contests and prizes, inquiry columns, correspondence, and internal advertising fostered a corporately devised participatory fandom that directly contributed to Sherlock Holmes's popularity. Tit-Bits audiences were invited and encouraged to imagine new scenarios for their favorite character that were validated through publication. Such practices not only created a unique identity for Sherlock Holmes fandom but also directly contributed to the creation and maintenance of Holmes's fictional world. With fandom studies reaching more and more audiences—both academic and popular—historicizing early fan practices like the early publication and reception of the Sherlock Holmes stories provides important insight into how audiences have historically responded to, and interacted with, fictional characters, and how they helped sustain and expand those characters' fictional worlds.
Biometric Quantization through Detection Rate Optimized Bit Allocation
Directory of Open Access Journals (Sweden)
C. Chen
2009-01-01
Full Text Available Extracting binary strings from real-valued biometric templates is a fundamental step in many biometric template protection systems, such as fuzzy commitment, fuzzy extractor, secure sketch, and helper data systems. Previous work has been focusing on the design of optimal quantization and coding for each single feature component, yet the binary string—concatenation of all coded feature components—is not optimal. In this paper, we present a detection rate optimized bit allocation (DROBA principle, which assigns more bits to discriminative features and fewer bits to nondiscriminative features. We further propose a dynamic programming (DP approach and a greedy search (GS approach to achieve DROBA. Experiments of DROBA on the FVC2000 fingerprint database and the FRGC face database show good performances. As a universal method, DROBA is applicable to arbitrary biometric modalities, such as fingerprint texture, iris, signature, and face. DROBA will bring significant benefits not only to the template protection systems but also to the systems with fast matching requirements or constrained storage capability.
Optical Switching and Bit Rates of 40 Gbit/s and above
DEFF Research Database (Denmark)
Ackaert, A.; Demester, P.; O'Mahony, M.;
2003-01-01
Optical switching in WDM networks introduces additional aspects to the choice of single channel bit rates compared to WDM transmission systems. The mutual impact of optical switching and bit rates of 40 Gbps and above is discussed.......Optical switching in WDM networks introduces additional aspects to the choice of single channel bit rates compared to WDM transmission systems. The mutual impact of optical switching and bit rates of 40 Gbps and above is discussed....
Smart focal plane technologies for ELT instruments
Cunningham, Colin R.; Ramsay-Howat, Suzanne K.; Garzon, Francisco; Parry, Ian R.; Prieto, Eric; Robertson, David J.; Zamkotsian, Frederic
2004-07-01
Smart Focal Planes are devices that enable the efficient sampling of a telescope's focal plane to feed spectroscopic and imaging instruments. Examples are integral field units (fiber and image slicers), cryogenic beam manipulators, and MOEMS (micro-opto-electromechanical systems) such as miniature slit shutters. These technologies are critical in making best use of the current 8m class telescopes for key science goals such as spectroscopic surveys of high redshift galaxies, and will be even more important for Extremely Large Telescope (ELT) instruments. In fact, the density of pixels in an ELT focal plane with several milliarcsecond resolution will mean that sub-sampling of the field will be needed even for imaging. We have proposed a joint European project to develop these technologies, building on expertise from partners in the UK, France, the Netherlands, Spain, Germany and others, and led by the UK. We describe the current status of these technologies, showing how they will contribute to the feasibility and performance of proposed instruments for ELTs, and concentrating on capabilities within Europe. We then outline the proposed future developments, highlighting the technical challenges, such as the difficulties of manufacturing and verifying complex image slicers with thousands of optical surfaces, and building highly reliable cryogenic mechanisms such as pick-off arms, beam steering mirrors and reconfigurble slit mechanisms.
BitTorrent系统中free riders的研究%A study on free riders in BitTorrent system
Institute of Scientific and Technical Information of China (English)
于魁飞; 程久军; 李玉宏; 马建
2007-01-01
针对BitTorent文件共享过程的特点,根据乐观疏通的思想,利用仿真实验分析了free riders对系统中其他类型的peers的下载进程的影响,给出了识别free riders的方法,提出了解决free riders问题的机制,并进行了仿真实验.结果表明:这种解决free riders问题的机制更好地激励了系统中的peers为系统做出贡献,从而获得利益;有效地控制了BitTorrent系统中的free riders,提高了系统的整体性能.
Bit Rate Reduction of FS-1015 Speech Coder Using Fuzzy ARTMAP and KSOFM Neural Networks
Directory of Open Access Journals (Sweden)
Ali Eslamzadeh
2009-03-01
Full Text Available The speech spectrum is very sensitive to linear predictive coding (LPC parameters, so small quantization errors may cause unstable synthesis filter. Line spectral pairs (LSPs are more efficient representations than LPC parameters. On the other hand, artificial neural networks (ANNs have been used successfully to improving the quality and also reduction the computational complexity of speech coders. This work proposes an efficient technique to reduce the bit rate of FS-1015 speech coder, while improving the performance. In this way, LSP parameters are used instead of the LPC parameters. In addition, neural vector quantizers based on Kohonen self-organizing feature map (KSOFM, with a modified-supervised training algorithm, and fuzzy ARTMAP are also employed to reduce the bit rate. By using the mentioned neural vector quantizer models, the quality of synthesized speech, in terms of mean opinion score (MOS, is improved 0.13 and 0.26, respectively. The execution time of proposed models, as compared to FS-1015 standard, is also reduced 27% and 43%, respectively.
A novel chaos-based bit-level permutation scheme for digital image encryption
Fu, Chong; Lin, Bin-bin; Miao, Yu-sheng; Liu, Xiao; Chen, Jun-jie
2011-11-01
Confidentiality is an important issue when digital images are transmitted over public networks, and encryption is the most useful technique employed for this purpose. Image encryption is somehow different from text encryption due to some inherent features of image such as bulk data capacity and high correlation among pixels, which are generally difficult to handle by conventional algorithms. Recently, chaos-based encryption has suggested a new and efficient way to deal with the intractable problems of fast and highly secure image encryption. This paper proposes a novel chaos-based bit-level permutation scheme for secure and efficient image cipher. To overcome the drawbacks of conventional permutation-only type image cipher, the proposed scheme introduced a significant diffusion effect in permutation procedure through a two-stage bit-level shuffling algorithm. The two-stage permutation operations are realized by chaotic sequence sorting algorithm and Arnold Cat map, respectively. Results of various types of analysis are interesting and indicate that the security level of the new scheme is competitive with that of permutation-diffusion type image cipher, while the computational complexity is much lower. Therefore the new scheme is a good candidate for real-time secure image communication applications.
DFT algorithms for bit-serial GaAs array processor architectures
Mcmillan, Gary B.
1988-01-01
Systems and Processes Engineering Corporation (SPEC) has developed an innovative array processor architecture for computing Fourier transforms and other commonly used signal processing algorithms. This architecture is designed to extract the highest possible array performance from state-of-the-art GaAs technology. SPEC's architectural design includes a high performance RISC processor implemented in GaAs, along with a Floating Point Coprocessor and a unique Array Communications Coprocessor, also implemented in GaAs technology. Together, these data processors represent the latest in technology, both from an architectural and implementation viewpoint. SPEC has examined numerous algorithms and parallel processing architectures to determine the optimum array processor architecture. SPEC has developed an array processor architecture with integral communications ability to provide maximum node connectivity. The Array Communications Coprocessor embeds communications operations directly in the core of the processor architecture. A Floating Point Coprocessor architecture has been defined that utilizes Bit-Serial arithmetic units, operating at very high frequency, to perform floating point operations. These Bit-Serial devices reduce the device integration level and complexity to a level compatible with state-of-the-art GaAs device technology.
Design of a pipelined 8-bit-serial single-flux-quantum microprocessor with multiple ALUs
Energy Technology Data Exchange (ETDEWEB)
Tanaka, M [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Kawamoto, T [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yamanashi, Y [Yokohama National University, 79-5 Tokiwa-dai, Hodogaya-ku, Yokohama 240-8501 (Japan); Kamiya, Y [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Akimoto, A [Yokohama National University, 79-5 Tokiwa-dai, Hodogaya-ku, Yokohama 240-8501 (Japan); Fujiwara, K [Yokohama National University, 79-5 Tokiwa-dai, Hodogaya-ku, Yokohama 240-8501 (Japan); Fujimaki, A [Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yoshikawa, N [Yokohama National University, 79-5 Tokiwa-dai, Hodogaya-ku, Yokohama 240-8501 (Japan); Terai, H [National Institute of Information and Communications Technology, 588-2 Iwaoka, Nishi-ku, Kobe 651-2492 (Japan); Yorozu, S [International Superconductivity Technology Center/Superconductivity Research Laboratory, 34 Miyukigaoka, Tsukuba 305-8501 (Japan)
2006-05-15
We have designed a pipelined 8-bit-serial single-flux-quantum microprocessor with multiple ALUs, called CORE1 {beta}. In the CORE1 {beta}, two ALUs connected in cascade enable us to perform two calculations on serial data using a register-to-register instruction, to enhance the peak performance. In addition, we have introduced pipelining to boost the performance. Although the pipelining is a difficult technique that requires a complex design in the datapath, we have implemented a simplified pipeline with seven stages by using two techniques. One is the separation of clock signals for pipelining and bit processing, and the other is the introduction of new buffers driven by independent clock signals for reading and writing flexibly in order to ease the difficulty in timing design between the register file and the ALUs. According to the logic simulation, the peak performance of the designed microprocessor is estimated to be 1500 million operations per second with a power consumption of 3.3 mW. We have fabricated the CORE1 {beta} chip by using the NEC 2.5 kA cm{sup -2} niobium standard process, and confirmed the correct operations of several instructions using high-speed clocks.
Design of a pipelined 8-bit-serial single-flux-quantum microprocessor with multiple ALUs
Tanaka, M.; Kawamoto, T.; Yamanashi, Y.; Kamiya, Y.; Akimoto, A.; Fujiwara, K.; Fujimaki, A.; Yoshikawa, N.; Terai, H.; Yorozu, S.
2006-05-01
We have designed a pipelined 8-bit-serial single-flux-quantum microprocessor with multiple ALUs, called CORE1 β. In the CORE1 β, two ALUs connected in cascade enable us to perform two calculations on serial data using a register-to-register instruction, to enhance the peak performance. In addition, we have introduced pipelining to boost the performance. Although the pipelining is a difficult technique that requires a complex design in the datapath, we have implemented a simplified pipeline with seven stages by using two techniques. One is the separation of clock signals for pipelining and bit processing, and the other is the introduction of new buffers driven by independent clock signals for reading and writing flexibly in order to ease the difficulty in timing design between the register file and the ALUs. According to the logic simulation, the peak performance of the designed microprocessor is estimated to be 1500 million operations per second with a power consumption of 3.3 mW. We have fabricated the CORE1 β chip by using the NEC 2.5 kA cm-2 niobium standard process, and confirmed the correct operations of several instructions using high-speed clocks.
Directory of Open Access Journals (Sweden)
Rashid A. Fayadh
2014-01-01
Full Text Available When receiving high data rate in ultra-wideband (UWB technology, many users have experienced multiple-user interference and intersymbol interference in the multipath reception technique. Structures have been proposed for implementing rake receivers to enhance their capabilities by reducing the bit error probability (Pe, thereby providing better performances by indoor and outdoor multipath receivers. As a result, several rake structures have been proposed in the past to reduce the number of resolvable paths that must be estimated and combined. To achieve this aim, we suggest two maximal ratio combiners based on the pulse sign separation technique, such as the pulse sign separation selective combiner (PSS-SC and the pulse sign separation partial combiner (PSS-PC to reduce complexity with fewer fingers and to improve the system performance. In the combiners, a comparator was added to compare the positive quantity of positive pulses and negative quantities of negative pulses to decide whether the transmitted bit was 1 or 0. The Pe was driven by simulation for multipath environments for impulse radio time-hopping binary phase shift keying (TH-BPSK modulation, and the results were compared with those of conventional selective combiners (C-SCs and conventional partial combiners (C-PCs.
DESIGN OF A RECONFIGURABLE DSP PROCESSOR WITH BIT EFFICIENT RESIDUE NUMBER SYSTEM
Directory of Open Access Journals (Sweden)
Chaitali Biswas Dutta
2012-10-01
Full Text Available Residue Number System (RNS, which originates from the Chinese Remainder Theorem, offers a promising future in VLSI because of its carry-free operations in addition, subtraction and multiplication. This property of RNS is very helpful to reduce the complexity of calculation in many applications. A residue number system represents a large integer using a set of smaller integers, called residues. But the area overhead, cost and speed not only depend on this word length, but also the selection of moduli, which is a very crucial step for residue system. This parameter determines bit efficiency, area, frequency etc. In this paper a new moduli set selection technique is proposed to improve bit efficiency which can be used to construct a residue system for digital signal processing environment. Subsequently, it is theoretically proved and illustrated using examples, that the proposed solution gives better results than the schemes reported in the literature. The novelty of the architecture is shown by comparison the different schemes reported in the literature. Using the novel moduli set, a guideline for a Reconfigurable Processor is presented here that can process some predefined functions. As RNS minimizes the carry propagation, the scheme can be implemented in Real Time Signal Processing & other fields where high speed computations are required.
Ahmed, Qasim Zeeshan
2014-04-01
The ever growing demand of higher data rates can now be addressed by exploiting cooperative diversity. This form of diversity has become a fundamental technique for achieving spatial diversity by exploiting the presence of idle users in the network. This has led to new challenges in terms of designing new protocols and detectors for cooperative communications. Among various amplify-and-forward (AF) protocols, the half duplex non-orthogonal amplify-and-forward (NAF) protocol is superior to other AF schemes in terms of error performance and capacity. However, this superiority is achieved at the cost of higher receiver complexity. Furthermore, in order to exploit the full diversity of the system an optimal precoder is required. In this paper, an optimal joint linear transceiver is proposed for the NAF protocol. This transceiver operates on the principles of minimum bit error rate (BER), and is referred as joint bit error rate (JBER) detector. The BER performance of JBER detector is superior to all the proposed linear detectors such as channel inversion, the maximal ratio combining, the biased maximum likelihood detectors, and the minimum mean square error. The proposed transceiver also outperforms previous precoders designed for the NAF protocol. © 2002-2012 IEEE.
A fast, low-power, 6-bit SAR ADC for readout of strip detectors in the LHCb Upgrade experiment.
Firlej, M; Idzik, M; Moron, J; Swientek, K
2014-01-01
The readout of silicon strip sensors in the upgraded Tracker System of Large Hadron Collider beauty (LHCb) experiment will require a novel complex Application Specific Integrated Circuit (ASIC). The ASIC will extract and digitise analogue signal from the sensor and subsequently will perform digital processing and serial data transmission. One of the key processing blocks, placed in each channel, will be an Analogue to Digital Converter (ADC). A prototype of fast, low-power 6-bit Successive Approximation Register (SAR) ADC was designed, fabricated and tested. The measurements of ADC prototypes confirmed simulation results showing excellent overall performance. In particular, very good resolution with Effective Number Of Bits (ENOB) 5.85 was obtained together with very low power consumption of 0.35 mW at 40 MS/s sampling rate. The results of the performed static and dynamic measurements confirm excellent ADC operation for higher sampling rates up to 80 MS/s.
A fast, low-power, 6-bit SAR ADC for readout of strip detectors in the LHCb Upgrade experiment
Firlej, M.; Fiutowski, T.; Idzik, M.; Moron, J.; Swientek, K.
2014-07-01
The readout of silicon strip sensors in the upgraded Tracker System of Large Hadron Collider beauty (LHCb) experiment will require a novel complex Application Specific Integrated Circuit (ASIC). The ASIC will extract and digitise analogue signal from the sensor and subsequently will perform digital processing and serial data transmission. One of the key processing blocks, placed in each channel, will be an Analogue to Digital Converter (ADC). A prototype of fast, low-power 6-bit Successive Approximation Register (SAR) ADC was designed, fabricated and tested. The measurements of ADC prototypes confirmed simulation results showing excellent overall performance. In particular, very good resolution with Effective Number Of Bits (ENOB) 5.85 was obtained together with very low power consumption of 0.35 mW at 40 MS/s sampling rate. The results of the performed static and dynamic measurements confirm excellent ADC operation for higher sampling rates up to 80 MS/s.
Message-passing algorithm for two-dimensional dependent bit allocation
Sagetong, Phoom; Ortega, Antonio
2003-05-01
We address the bit allocation problem in scenarios where there exist two-dimensional (2D) dependencies in the bit allocation, i.e., where the allocation involves a 2D set of coding units (e.g., DCT blocks in standard MPEG coding) and where the rate-distortion (RD) characteristics of each coding unit depend on one or more of the other coding units. These coding units can be located anywhere in 2D space. As an example we consider MPEG-4 intra-coding where, in order to further reduce the redundancy between coefficients, both the DC and certain of the AC coefficients of each block are predicted from the corresponding coefficients in either the previous block in the same line (to the left) or the one above the current block. To find the optimal solution may be a time-consuming problem, given that the RD characteristics of each block depend on those of the neighbors. Greedy search approaches are popular due to their low complexity and low memory consumption, but they may be far from optimal due to the dependencies in the coding. In this work, we propose an iterative message-passing technique to solve 2D dependent bit allocation problems. This technique is based on (i) Soft-in/Soft-out (SISO) algorithms first used in the context of Turbo codes, (ii) a grid model, and (iii) Lagrangian optimization techniques. In order to solve this problem our approach is to iteratively compute the soft information of a current DCT block (intrinsic information) and pass the soft decision (extrinsic information) to other nearby DCT block(s). Since the computational complexity is also dominated by the data generation phase, i.e., in the Rate-Distortion (RD) data population process, we introduce an approximation method to eliminate the need to generate the entire set of RD points. Experimental studies reveal that the system that uses the proposed message-passing algorithm is able to outperform the greedy search approach by 0.57 dB on average. We also show that the proposed algorithm requires
Annual Report: Support Research for Development of Improved Geothermal Drill Bits
Energy Technology Data Exchange (ETDEWEB)
Hendrickson, R.R.; Winzenried, R.W.; Jones, A.H.; Green, S.J.
1978-07-01
The work reported herein is a continuation of the program initiated under DOE contract E(10-1)-1546* entitled "Program to Design and Experimentally Test an Improved Geothermal Bit"; the program is now DOE Contract EG-76-C-1546*. The objective of the program has been to accelerate the commercial availability of a tolling cutter drill bit for geothermal applications. Data and experimental tests needed to develop a bit suited to the harsh thermal, abrasive, and chemical environment of the more problematic geothermal wells, including those drilled with air, have been obtained. Efforts were directed at the improvement of both the sealed (lubricated) and unsealed types of bits. The unsealed bit effort included determination of the rationale for materials selection, the selection of steels for the bit body, cutters, and bearings, the selection of tungsten carbide alloys for the friction bearing, and preliminary investigation of optimized tungsten carbide drilling inserts. Bits build** with the new materials were tested under stimulated wellbore conditions. The sealed bit effort provided for the evaluation of candidate high temperature seals and lubricants, utilizing two specially developed test apparatus which simulate the conditions found in a sealed bit operating in a geothermal wellbore. Phase I of the program was devoted largely to (1) the study of the geothermal environment and the failure mechanisms of existing geothermal drill bits, (2) the design and construction of separate facilities for testing both drill-bit seals and full-scale drill bits under simulated geothermal drilling conditions, and (3) fabrication of the MK-I research drill bits from high-temperature steels, and testing in the geothermal drill-bit test facility. The work accomplished in Phase I is reported in References 1 through 9. In Phase II, the first generation experimental bits were tested in the geothermal drill-bit test facility. Test results indicated that hardness retention at temperature
The digital agenda of virtual currencies: Can BitCoin become a global currency?
CIAIAN PAVEL; RAJCANIOVA MIROSLAVA; KANCS D'ARTIS
2015-01-01
This paper identifies and analyzes BitCoin features which may facilitate BitCoin to become a global currency, as well as characteristics which may impede the use of BitCoin as a medium of exchange, a unit of account and a store of value, and compares BitCoin with standard currencies with respect to the main functions of money. Among all analyzed BitCoin features, the extreme price volatility stands out most clearly compared to standard currencies. In order to understand the reasons for such e...
Heat Generation During Bone Drilling: A Comparison Between Industrial and Orthopaedic Drill Bits.
Hein, Christopher; Inceoglu, Serkan; Juma, David; Zuckerman, Lee
2017-02-01
Cortical bone drilling for preparation of screw placement is common in multiple surgical fields. The heat generated while drilling may reach thresholds high enough to cause osteonecrosis. This can compromise implant stability. Orthopaedic drill bits are several orders more expensive than their similarly sized, publicly available industrial counterparts. We hypothesize that an industrial bit will generate less heat during drilling, and the bits will not generate more heat after multiple cortical passes. We compared 4 4.0 mm orthopaedic and 1 3.97 mm industrial drill bits. Three types of each bit were drilled into porcine femoral cortices 20 times. The temperature of the bone was measured with thermocouple transducers. The heat generated during the first 5 drill cycles for each bit was compared to the last 5 cycles. These data were analyzed with analysis of covariance. The industrial drill bit generated the smallest mean increase in temperature (2.8 ± 0.29°C) P industrial bit generated less heat during drilling than its orthopaedic counterparts. The bits maintained their performance after 20 drill cycles. Consideration should be given by manufacturers to design differences that may contribute to a more efficient cutting bit. Further investigation into the reuse of these drill bits may be warranted, as our data suggest their efficiency is maintained after multiple uses.
Layout parameter analysis in Shannon expansion theorem based on 32 bit adder circuit
Directory of Open Access Journals (Sweden)
C. Senthilpari
2017-02-01
Full Text Available The 1-bit adder circuits are schematized using pass transistor logic (PTL technique, that’s optimized by the Shannon expansion theorem. The proposed 32 bit carry increment adder (CIA circuit is designed by bit slice method. The CIA adder layout gives tremendous change compared to existing author results. The proposed circuit achieved better performance on power consumption, speed, throughput, and area. The 32-bit adder circuits are implemented in various types of 1-bit adder cells, such as Shannon, Mixed-Shannon and MCIT-7T. Furthermore, the 32-bit CIA adder layout is furtherly investigated for RLC interconnect parameter such as capacitive impedance, inductive impedance, power factor sin ϕ, tan ϕ for applying frequency. The 32 bit adder circuit acts in a better way than existing circuits in terms of power dissipation, delay, throughput, latency, power factor, sin ϕ and tan ϕ.
Chaotic laser based physical random bit streaming system with a computer application interface
Shinohara, Susumu; Arai, Kenichi; Davis, Peter; Sunada, Satoshi; Harayama, Takahisa
2017-03-01
We demonstrate a random bit streaming system that uses a chaotic laser as its physical entropy source. By performing real-time bit manipulation for bias reduction, we were able to provide the memory of a personal computer with a constant supply of ready-to-use physical random bits at a throughput of up to 4 Gbps. We pay special attention to the end-to-end entropy source model describing how the entropy from physical sources is converted into bit entropy. We confirmed the statistical quality of the generated random bits by revealing the pass rate of the NIST SP800-22 test suite to be 65 % to 75 %, which is commonly considered acceptable for a reliable random bit generator. We also confirmed the stable operation of our random bit steaming system with long-term bias monitoring.
FPGA Implementation of an Area Optimized Architecture for 128 bit AES Algorithm
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S Ramanathan
2016-05-01
Full Text Available This paper aims at FPGA Implementation of an Area Optimized Architecture for 128 bit AES Algorithm. The conventional designs use a separate module for 32 bit byte substitution and 128 bit byte substitution. The 32 bit byte substitution is used in round key generation and the 128 bit byte substitution is used in the rounds. This report presents a modified architecture of 128 bit byte substitution module using a single 32 bit byte substitution module to reduce area.The AES encryption and decryption algorithm were designed using Verilog HDL. The functionality of the modules were checked using ModelSim. The simulations were carried out in ModelSim and Quartus II. The algorithm was implemented in FPGA and achieved a 2% reduction in the total logic element utilization
Multi-bit quantum random number generation by measuring positions of arrival photons
Yan, Qiurong; Zhao, Baosheng; Liao, Qinghong; Zhou, Nanrun
2014-10-01
We report upon the realization of a novel multi-bit optical quantum random number generator by continuously measuring the arrival positions of photon emitted from a LED using MCP-based WSA photon counting imaging detector. A spatial encoding method is proposed to extract multi-bits random number from the position coordinates of each detected photon. The randomness of bits sequence relies on the intrinsic randomness of the quantum physical processes of photonic emission and subsequent photoelectric conversion. A prototype has been built and the random bit generation rate could reach 8 Mbit/s, with random bit generation efficiency of 16 bits per detected photon. FPGA implementation of Huffman coding is proposed to reduce the bias of raw extracted random bits. The random numbers passed all tests for physical random number generator.
Multi-Bit Data Hiding Scheme for Compressing Secret Messages
Directory of Open Access Journals (Sweden)
Wen-Chung Kuo
2015-11-01
Full Text Available The goal of data hiding techniques usually considers two issues, embedding capacity and image quality. Consequently, in order to achieve high embedding capacity and good image quality, a data hiding scheme combining run-length encoding (RLE with multi-bit embedding is proposed in this paper. This work has three major contributions. First, the embedding capacity is increased 62% because the secret message is compressed before embedding into the cover image. Secondly, the proposed scheme keeps the multi-bit generalized exploiting modification direction (MGEMD characteristics, which are effective to reduce modified pixels in the cover image and to maintain good stego image quality. Finally, the proposed scheme can prevent modern steganalysis methods, such as RS steganalysis and SPAM (subtractive pixel adjacency matrix, and is compared to MiPOD (minimizing the power of the optimal detector scheme. From our simulation results and security discussions, we have the following results: First, there are no perceivable differences between the cover images and stego images from human inspection. For example, the average PSNR of stego images is about 44.61 dB when the secret message (80,000 bits is embedded for test cover images (such as airplane, baboon, Lena of size 512×512. Secondly, Appl. Sci. 2015, 5 1034 on average, 222,087 pixels were not modified after embedding for the cover image. That is to say, 12% less pixels are modified as compared to the MGEMD method. From the performance discussions, the proposed scheme achieves high embedding capacity and good image quality, but also maintains stego image security.
All-optical pseudorandom bit sequences generator based on TOADs
Sun, Zhenchao; Wang, Zhi; Wu, Chongqing; Wang, Fu; Li, Qiang
2016-03-01
A scheme for all-optical pseudorandom bit sequences (PRBS) generator is demonstrated with optical logic gate 'XNOR' and all-optical wavelength converter based on cascaded Tera-Hertz Optical Asymmetric Demultiplexer (TOADs). Its feasibility is verified by generation of return-to-zero on-off keying (RZ-OOK) 263-1 PRBS at the speed of 1 Gb/s with 10% duty radio. The high randomness of ultra-long cycle PRBS is validated by successfully passing the standard benchmark test.
Bit-Interleaved Coded Multiple Beamforming with Constellation Precoding
Park, Hong Ju
2009-01-01
In this paper, we present the diversity order analysis of bit-interleaved coded multiple beamforming (BICMB) combined with the constellation precoding scheme. Multiple beamforming is realized by singular value decomposition of the channel matrix which is assumed to be perfectly known to the transmitter as well as the receiver. Previously, BICMB is known to have a diversity order bound related with the product of the code rate and the number of parallel subchannels, losing the full diversity order in some cases. In this paper, we show that BICMB combined with the constellation precoder and maximum likelihood detection achieves the full diversity order. We also provide simulation results that match the analysis.
Design of high-bit-rate coherent communication links
Konyshev, V. A.; Leonov, A. V.; Nanii, O. E.; Novikov, A. G.; Treshchikov, V. N.; Ubaydullaev, R. R.
2016-12-01
We report an analysis of the problems encountered in the design of modern high-bit-rate coherent communication links. A phenomenological communication link model is described, which is suitable for solving applied tasks of the network design with nonlinear effects taken into account. We propose an engineering approach to the design that is based on the use of fundamental nonlinearity coefficients calculated in advance for the experimental configurations of communication links. An experimental method is presented for calculating the nonlinearity coefficient of communication links. It is shown that the proposed approach allows one to successfully meet the challenges in designing communication networks.
Distribution of digital games via BitTorrent
DEFF Research Database (Denmark)
Drachen, Anders; Bauer, Kevin; Veitch, Robert W. D.
2011-01-01
distribution across game titles and game genres. This paper presents the first large-scale, open-method analysis of the distribution of digital game titles, which was conducted by monitoring the BitTorrent peer-to-peer (P2P) file-sharing protocol. The sample includes 173 games and a collection period of three...... months from late 2010 to early 2011. With a total of 12.6 million unique peers identified, it is the largest examination of game piracy via P2P networks to date. The study provides findings that reveal the magnitude of game piracy, the time-frequency of game torrents, which genres that get pirated...
INFORMATION SECURITY THROUGH IMAGE WATERMARKING USING LEAST SIGNIFICANT BIT ALGORITHM
Directory of Open Access Journals (Sweden)
Puneet Kr Sharma
2012-05-01
Full Text Available The rapid advancement of internet has made it easier to send the data/image accurate and faster to the destination. Besides this, it is easier to modify and misuse the valuable information through hacking at the same time. In order to transfer the data/image securely to the destination without any modifications, there are many approaches like Cryptography, Watermarking and Steganography. This paper presents the general overview of image watermarking and different security issues. In this paper, Image Watermarking using Least Significant Bit (LSB algorithm has been used for embedding the message/logo into the image. This work has been implemented through MATLAB.
Generalized dual-plane digital holographic imaging method
Wang, Fengpeng; Wang, Dayong; Panezai, Spozmai; Rong, Lu; Wang, Yunxin; Zhao, Jie
2016-12-01
A generalized dual-plane technique for digital holographic imaging is proposed. Two holograms are recorded at two slightly displaced planes. The complex amplitude of the plane reference wave is obtained according to the measured intensity of the reference beam and the spectrum of hologram. The holograms are modified with the known information of the reference wave. Then, the modified holograms are reconstructed by the dual-plane algorithm. The zero-order and the twin images are removed in the reconstructed image. The simulation and experiments demonstrate that this method is valid for both on-axis and off-axis digital holography and high resolution reconstruction is achieved even with a very small offset angle of the reference beam.
Burdin, Vladimir A.; Kartashevsky, Vyacheslav G.; Grigorov, Igor V.
2016-03-01
This paper presents «reception in general with bit-by-bit decision-making» algorithm, which is the alternative to Viterbi algorithm. It is proposed to use it for fiber-optic transmission systems. It's features is compared with the Viterbi algorithm for digital signal processing in optical communication channels.
Hiwasa, Takeshi; Morishita, Junji; Hatanaka, Shiro; Ohki, Masafumi; Toyofuku, Fukai; Higashida, Yoshiharu
2009-01-01
Our purpose in this study was to examine the potential usefulness of liquid-crystal display (LCD) monitors having the capability of rendering higher than 8 bits in display-bit depth. An LCD monitor having the capability of rendering 8, 10, and 12 bits was used. It was calibrated to the grayscale standard display function with a maximum luminance of 450 cd/m(2) and a minimum of 0.75 cd/m(2). For examining the grayscale resolution reported by ten observers, various simple test patterns having two different combinations of luminance in 8, 10, and 12 bits were randomly displayed on the LCD monitor. These patterns were placed on different uniform background luminance levels, such as 0, 50, and 100%, for maximum luminance. All observers participating in this study distinguished a smaller difference in luminance than one gray level in 8 bits irrespective of background luminance levels. As a result of the adaptation processes of the human visual system, observers distinguished a smaller difference in luminance as the luminance level of the test pattern was closer to the background. The smallest difference in luminance that observers distinguished was four gray levels in 12 bits, i.e., one gray level in 10 bits. Considering the results obtained by use of simple test patterns, medical images should ideally be displayed on LCD monitors having 10 bits or greater so that low-contrast objects with small differences in luminance can be detected and for providing a smooth gradation of grayscale.
Arnold's Projective Plane and -Matrices
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K. Uchino
2010-01-01
Full Text Available We will explain Arnold's 2-dimensional (shortly, 2D projective geometry (Arnold, 2005 by means of lattice theory. It will be shown that the projection of the set of nontrivial triangular -matrices is the pencil of tangent lines of a quadratic curve on Arnold's projective plane.
Affine Contractions on the Plane
Celik, D.; Ozdemir, Y.; Ureyen, M.
2007-01-01
Contractions play a considerable role in the theory of fractals. However, it is not easy to find contractions which are not similitudes. In this study, it is shown by counter examples that an affine transformation of the plane carrying a given triangle onto another triangle may not be a contraction even if it contracts edges, heights or medians.…
Distributed storage in the plane
Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper
2013-01-01
We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can
Distributed storage in the plane
Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper
2014-01-01
We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can
Plane and parabolic solar panels
Sales, J H O
2009-01-01
We present a plane and parabolic collector that absorbs radiant energy and transforms it in heat. Therefore we have a panel to heat water. We study how to increment this capture of solar beams onto the panel in order to increase its efficiency in heating water.
Distributed storage in the plane
Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper
2013-01-01
We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can
Distributed storage in the plane
Altman, Eitan; Avrachenkov, Konstatin; Goseling, Jasper
2014-01-01
We consider storage devices located in the plane according to a general point process and specialize the results for the homogeneous Poisson process. A large data file is stored at the storage devices, which have limited storage capabilities. Hence, they can only store parts of the data. Clients can
Directory of Open Access Journals (Sweden)
Madeiro Francisco
2010-01-01
Full Text Available Abstract This paper presents an alternative method for determining exact expressions for the bit error probability (BEP of modulation schemes subject to Nakagami- fading. In this method, the Nakagami- fading channel is seen as an additive noise channel whose noise is modeled as the ratio between Gaussian and Nakagami- random variables. The method consists of using the cumulative density function of the resulting noise to obtain closed-form expressions for the BEP of modulation schemes subject to Nakagami- fading. In particular, the proposed method is used to obtain closed-form expressions for the BEP of -ary quadrature amplitude modulation ( -QAM, -ary pulse amplitude modulation ( -PAM, and rectangular quadrature amplitude modulation ( -QAM under Nakagami- fading. The main contribution of this paper is to show that this alternative method can be used to reduce the computational complexity for detecting signals in the presence of fading.
Multiuser subcarriers and bit allocation combining adaptive mapping for SC-FDMA system
Institute of Scientific and Technical Information of China (English)
ZHANG Yu-mei; XIN Yu; YANG Da-cheng
2008-01-01
In this article, a multiuser single carrier frequency division multiple access (SC-FDMA) system is considered, based on which an adaptive subcarrier and bit allocation algorithm is investigated. The algorithm has been used to achieve a subcarrier mapping mode in this system, which combines the advantages of single- and multi-carrier transmissions, such as, low peak to average power ratio, orthogonality of signals of different users, and low complexity. Simulation results show that it has a similar performance as that of the adaptive allocation algorithm in the orthogonal frequency division multiple (OFDM) system and the proposed mapping mode has a performance gain over the two existing mapping modes at the link level.
A 16-bit Coherent Ising Machine for One-Dimensional Ring and Cubic Graph Problems
Takata, Kenta; Hamerly, Ryan; Haribara, Yoshitaka; Maruo, Daiki; Tamate, Shuhei; Sakaguchi, Hiromasa; Utsunomiya, Shoko; Yamamoto, Yoshihisa
2016-01-01
Many tasks in modern life, such as efficient traveling, image processing and integrated circuit optimization, are modeled as complex combinatorial optimization problems. Such problems can be mapped to finding a ground state of the Ising Hamiltonian, thus various physical systems have been studied to emulate and solve this Ising problem. Recently, networks of mutually injected optical oscillators, called coherent Ising machines, have been developed as promising solvers for the problem, benefiting from programmability, scalability and room temperature operation. Here, we report a 16-bit coherent Ising machine with a network of time-division-multiplexed femtosecond degenerate optical parametric oscillators. The system experimentally gives more than 99.6 % of success rates for one-dimensional Ising ring and nondeterministic polynomial-time (NP) hard instances. The experimental and numerical results indicate that gradual pumping of the network combined with multimode dynamics of femtosecond pulses can improve its ...
Threshold-Based Bit Error Rate for Stopping Iterative Turbo Decoding in a Varying SNR Environment
Mohamad, Roslina; Harun, Harlisya; Mokhtar, Makhfudzah; Adnan, Wan Azizun Wan; Dimyati, Kaharudin
2017-01-01
Online bit error rate (BER) estimation (OBE) has been used as a stopping iterative turbo decoding criterion. However, the stopping criteria only work at high signal-to-noise ratios (SNRs), and fail to have early termination at low SNRs, which contributes to an additional iteration number and an increase in computational complexity. The failure of the stopping criteria is caused by the unsuitable BER threshold, which is obtained by estimating the expected BER performance at high SNRs, and this threshold does not indicate the correct termination according to convergence and non-convergence outputs (CNCO). Hence, in this paper, the threshold computation based on the BER of CNCO is proposed for an OBE stopping criterion (OBEsc). From the results, OBEsc is capable of terminating early in a varying SNR environment. The optimum number of iterations achieved by the OBEsc allows huge savings in decoding iteration number and decreasing the delay of turbo iterative decoding.
Bit-Based Joint Source-Channel Decoding of Huffman Encoded Markov Multiple Sources
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Weiwei Xiang
2010-04-01
Full Text Available Multimedia transmission over time-varying channels such as wireless channels has recently motivated the research on the joint source-channel technique. In this paper, we present a method for joint source-channel soft decision decoding of Huffman encoded multiple sources. By exploiting the a priori bit probabilities in multiple sources, the decoding performance is greatly improved. Compared with the single source decoding scheme addressed by Marion Jeanne, the proposed technique is more practical in wideband wireless communications. Simulation results show our new method obtains substantial improvements with a minor increasing of complexity. For two sources, the gain in SNR is around 1.5dB by using convolutional codes when symbol-error rate (SER reaches 10-2 and around 2dB by using Turbo codes.
A novel dynamic frame rate control algorithm for H.264 low-bit-rate video coding
Institute of Scientific and Technical Information of China (English)
Yang Jing; Fang Xiangzhong
2007-01-01
The goal of this paper is to improve human visual perceptual quality as well as coding efficiency of H.264 video at low bit rate conditions by adaptively adjusting the number of skipped frames. The encoding frames ale selected according to the motion activity of each frame and the motion accumulation of successive frames. The motion activity analysis is based on the statistics of motion vectors and with consideration of the characteristics of H. 264 coding standard. A prediction model of motion accumulation is proposed to reduce complex computation of motion estimation. The dynamic encoding frame rate control algorithm is applied to both the frame level and the GOB (Group of Macroblocks) level. Simulation is done to compare the performance of JM76 with the proposed frame level scheme and GOB level scheme.
Two-plane symmetry in the structural organization of man.
Ermolenko, A E
2005-01-01
Manifestations of symmetry in the human structural organization in ontogenesis and phylogenetic development are analysed. A concept of macrobiocrystalloid with inherent complex symmetry is proposed for the description of the human organism in its integrity. The symmetry can be characterized as two-plane radial (quadrilateral), where the planar symmetry is predominant while the layout of organs of radial symmetry is subordinated to it. Out of the two planes of symmetry (sagittal and horizontal), the sagittal plane is predominant: (a) the location of the organs is governed by two principles: in compliance with the symmetry planes and in compliance with the radial symmetry around cavities; (b) the location of the radial symmetry organs is also governed by the principle of two-plane symmetry; (c) out of the four antimeres of two-plane symmetry, two are paired while the other two have merged into one organ; (d) some organs which are antimeres relative to the horizontal plane are located at the cranial end of the organism (sensory organs, cerebrum-cerebellum, heart-spleen and others). The two-plane symmetry is formed by two mechanisms--(a) the impact of morphogenetic fields of the whole crystalloid organism during embriogenesis and (b) genetic mechanisms of the development of chromosomes having two-plane symmetry. When comparing mineral and biological entities we should consider not the whole immobile crystal but only the active superficial part of a growing or dissolving crystal, the interface between the crystal surface and the crystal-forming environment which directly controls crystal growth and adapts itself to it, as well as crystal feed stock expressed in the structure of concentration flows. The symmetry of the chromosome, of the embrion at the early stages of cell cleavage as well as of some organs and systems in their phylogenetic development is described.
Gravitational Couplings for y-Gop-Planes
Ospina-Giraldo, J F
2000-01-01
The Wess-Zumino action for y deformed and generalized orientifold planes (yGOp-planes) is presented and one power expantion is realized from which processes that involves yGOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally non-standard yGOp-planes are showed.
Linear Instability of the Plane Couette and Plane Poiseuille Flows
Chefranov, Sergey G
2015-01-01
We show possibility of the Plane Couette (PC) flow instability for Reynolds number Re>Reth=140. This new result of the linear hydrodynamic stability theory is obtained on the base of refusal from the traditionally used assumption on longitudinal periodicity of the disturbances along the direction of the fluid flow. We found that earlier existing understanding on the linear stability of this flow for any arbitrary large Reynolds number is directly related with an assumption on the separation of the variables of the spatial variability for the disturbance field and their periodicity in linear theory of stability. By the refusal from the pointed assumptions also for the Plane Poiseuille (PP) flow, we get a new threshold Reynolds value Reth=1040 that with 4% accuracy agrees with the experiment contrary to more than 500% discrepancy for the earlier known estimate Reth=5772 obtained in the frame of the linear theory but when using the "normal" disturbance form (S. A. Orszag, 1971).
Learning may need only a few bits of synaptic precision
Baldassi, Carlo; Gerace, Federica; Lucibello, Carlo; Saglietti, Luca; Zecchina, Riccardo
2016-05-01
Learning in neural networks poses peculiar challenges when using discretized rather then continuous synaptic states. The choice of discrete synapses is motivated by biological reasoning and experiments, and possibly by hardware implementation considerations as well. In this paper we extend a previous large deviations analysis which unveiled the existence of peculiar dense regions in the space of synaptic states which accounts for the possibility of learning efficiently in networks with binary synapses. We extend the analysis to synapses with multiple states and generally more plausible biological features. The results clearly indicate that the overall qualitative picture is unchanged with respect to the binary case, and very robust to variation of the details of the model. We also provide quantitative results which suggest that the advantages of increasing the synaptic precision (i.e., the number of internal synaptic states) rapidly vanish after the first few bits, and therefore that, for practical applications, only few bits may be needed for near-optimal performance, consistent with recent biological findings. Finally, we demonstrate how the theoretical analysis can be exploited to design efficient algorithmic search strategies.
STEGANOGRAFI DENGAN CHAOTIC LEAST SIGNIFICANT BIT ENCODING PADA TELEPON GENGGAM
Directory of Open Access Journals (Sweden)
Susany Soplanit
2007-01-01
Full Text Available The issues of security in mobile phone in recent days become crucial. Many privacy or secretly data is stored using unsecured protocol or sometimes without the security procedures at all. This will lead to great awareness about security in mobile phone. The effective ways to secure data are steganography and cryptography. The first one concentrate to data hiding in a certain media. In this paper, we present Chaotic Least Significant Bit Encoding (CLSBE as a steganography method in our system design. The experiment results show that hidden messages in PNG form can be retrieved correctly. The implementation of system in emulator works well but depends on mobile phone features and environment. Abstract in Bahasa Indonesia : Telepon genggam saat ini dapat digunakan untuk menyimpan data-data yang bersifat pribadi atau rahasia, oleh karena itu pengamanan data pada telepon genggam akan menjadi hal yang penting di masa ini ataupun di masa yang akan datang. Sistem pengamanan data yang efektif pada telepon genggam selain kriptografi adalah Steganografi yaitu penyembunyian data dalam sebuah media. Dalam perancangan ini metode yang digunakan adalah Chaotic Least Significant Bit Encoding (CLSBE. Hasil pengujian membuktikan bahwa pesan yang tersembunyi dalam citra digital dengan format PNG masih dapat diambil kembali dengan benar. Implementasi pada emulator telah berjalan dengan baik, namun untuk telepon genggam perlu penyesuaian dengan fasilitas pada telepon tersebut. Kata kunci: CLSBE, steganografi, stego-image, cover-image.
Single-Cycle Bit Permutations with MOMR Execution
Institute of Scientific and Technical Information of China (English)
Ruby B. Lee; Xiao Yang; Zhi-Jie Jerry Shi
2005-01-01
Secure computing paradigms impose new architectural challenges for general-purpose processors. Cryptographic processing is needed for secure communications, storage, and computations. We identify two categories of operations in symmetric-key and public-key cryptographic algorithms that are not common in previous general-purpose workloads:advanced bit operations within a word and multi-word operations. We define MOMR (Multiple Operands Multiple Results)execution or datarich execution as a unified solution to both challenges. It allows arbitrary n-bit permutations to be achieved in one or two cycles, rather than O(n) cycles as in existing RISC processors. It also enables significant acceleration of multiword multiplications needed by public-key ciphers. We propose two implementations of MOMR: one employs only hardware changes while the other uses Instruction Set Architecture (ISA) support. We show that MOMR execution leverages available resources in typical multi-issue processors with minimal additional cost. Multi-issue processors enhanced with MOMR units provide additional speedup over standard multi-issue processors with the same datapath. MOMR is a general architectural solution for word-oriented processor architectures to incorporate datarich operations.
A 16-Bit Fully Functional Single Cycle Processor
Directory of Open Access Journals (Sweden)
Nidhi Maheshwari
2011-08-01
Full Text Available The existing commercial microprocessors are provided as black box units, with which users are unable to monitor internal signals and operation process, neither can they modify the original structure. Inorder to solve this problem 16-bit fully functional single cycle processor is designed in terms of its architecture and its functional capabilities. The procedure of design and verification for a 16-bit processor is introduced in this paper. The key architecture elements are being described, as well as the hardware block diagram and internal structure. The summary of instruction set is presented. This processor is modify as a Very High Speed Integrated Circuit Hardware Description Language (VHDL and gives access to every internal signal. In order to consume fewer resources, the design of arithmetic logical unit (ALU is optimized. The RTL views and verified simulation results of processor are shown in this paper. The synthesis report of the design is also described. The design architecture is written in Very High Speed Integrated Circuit Hardware Description Language (VHDL code using Xilinx ISE 9.2i tool for synthesis and simulation.
Giga-bit optical data transmission module for Beam Instrumentation
Roedne, L T; Cenkeramaddi, L R; Jiao, L
Particle accelerators require electronic instrumentation for diagnostic, assessment and monitoring during operation of the transferring and circulating beams. A sensor located near the beam provides an electrical signal related to the observable quantity of interest. The front-end electronics provides analog-to-digital conversion of the quantity being observed and the generated data are to be transferred to the external digital back-end for data processing, and to display to the operators and logging. This research project investigates the feasibility of radiation-tolerant giga-bit data transmission over optic fibre for beam instrumentation applications, starting from the assessment of the state of the art technology, identification of challenges and proposal of a system level solution, which should be validated with a PCB design in an experimental setup. Radiation tolerance of 10 kGy (Si) Total Ionizing Dose (TID) over 10 years of operation, Bit Error Rate (BER) 10-6 or better. The findings and results of th...
Improved Hardfacing for Drill Bits and Drilling Tools
Sue, Albert; Sreshta, Harry; Qiu, Bao He
2011-01-01
New flame spray hardfacing, DSH (DuraShell® Steel Hardfacing, US patent pending), was developed to improve thermal conductivity, abrasion wear, and erosion resistance for subterranean drilling application. The materials consisted of spherical cast WC/W2C and Ni-Si-B alloy powders. The hardfacing compositions were tailored for various processes such as flame spray and laser cladding. Typically, the hardfacing comprised hard tungsten carbide particles being uniformly distributed in a tough Ni-alloy matrix. The hardness of WC/W2C exceeded 2300 Hv.3 and that of Ni-alloy matrix varied from about 400 to 700 Hv.3. High- and low-stress abrasion resistances of these hardfacing materials were characterized and compared to the conventional hard coatings of cast WC/W2C and Ni-Cr-Si-B-Fe. The increase in thermal, wear, and erosion resistances of the hardfacing improved the durability of PDC (polycrystalline diamond compact) steel body bit and drilling tools and their cost-effective performance. Several case studies of DSH hardfacings on drill bits were described.
A Short Introduction to Bit-String Physics
Noyes, H P
1997-01-01
This paper starts with a personal memoir of how some significant ideas arose and events took place during the period from 1972, when I first encountered Ted Bastin, to 1979, when I proposed the foundation of ANPA. I then discuss program universe, the fine structure paper and its rejection, the quantitative results up to ANPA 17 and take a new look at the handy-dandy formula. Following this historical material is a first pass at establishing new foundations for bit-string physics. An abstract model for a laboratory notebook and an historical record are developed, culminating in the bit-string representation. I set up a tic-toc laboratory with two synchronized clocks and show how this can be used to analyze arbitrary incoming data. This allows me to discuss (briefly) finite and discrete Lorentz transformations, commutation relations, and scattering theory. Earlier work on conservation laws in 3- and 4-events and the free space Dirac and Maxwell equations is cited. The paper concludes with a discussion of the qu...
Statistical mechanics analysis of thresholding 1-bit compressed sensing
Xu, Yingying; Kabashima, Yoshiyuki
2016-08-01
The one-bit compressed sensing framework aims to reconstruct a sparse signal by only using the sign information of its linear measurements. To compensate for the loss of scale information, past studies in the area have proposed recovering the signal by imposing an additional constraint on the l 2-norm of the signal. Recently, an alternative strategy that captures scale information by introducing a threshold parameter to the quantization process was advanced. In this paper, we analyze the typical behavior of thresholding 1-bit compressed sensing utilizing the replica method of statistical mechanics, so as to gain an insight for properly setting the threshold value. Our result shows that fixing the threshold at a constant value yields better performance than varying it randomly when the constant is optimally tuned, statistically. Unfortunately, the optimal threshold value depends on the statistical properties of the target signal, which may not be known in advance. In order to handle this inconvenience, we develop a heuristic that adaptively tunes the threshold parameter based on the frequency of positive (or negative) values in the binary outputs. Numerical experiments show that the heuristic exhibits satisfactory performance while incurring low computational cost.
Statistical mechanics approach to 1-bit compressed sensing
Xu, Yingying; Kabashima, Yoshiyuki
2013-02-01
Compressed sensing is a framework that makes it possible to recover an N-dimensional sparse vector x∈RN from its linear transformation y∈RM of lower dimensionality M entry of y to recover x was recently proposed. This is often termed 1-bit compressed sensing. Here, we analyze the typical performance of an l1-norm-based signal recovery scheme for 1-bit compressed sensing using statistical mechanics methods. We show that the signal recovery performance predicted by the replica method under the replica symmetric ansatz, which turns out to be locally unstable for modes breaking the replica symmetry, is in good consistency with experimental results of an approximate recovery algorithm developed earlier. This suggests that the l1-based recovery problem typically has many local optima of a similar recovery accuracy, which can be achieved by the approximate algorithm. We also develop another approximate recovery algorithm inspired by the cavity method. Numerical experiments show that when the density of nonzero entries in the original signal is relatively large the new algorithm offers better performance than the abovementioned scheme and does so with a lower computational cost.
Design of Low Noise 16-bit CMOS Digitally Controlled Oscillator
Directory of Open Access Journals (Sweden)
Nitin Kumar
2012-02-01
Full Text Available In this paper, a new differential delay cell is proposed and 16-bit Digital Controlled Oscillator (DCO based on proposed delay cell is designed. The 16-bit DCO consist of 4-stages differential delay cell in ring structure and a digital control scheme has been used to improved noise characteristics. The structure of the DCO utilizes dual delay path techniques to achieve high oscillation frequency and awide tuning range. The DCO circuit has been simulated in SPICE with 0.5μm technology operating with supply voltage of 5V. DCO achieved a controllable frequency range of [1.7324-4.8649] GHz with a tuningrange of 3.1325GHz (≈64%. The measured output noise is -161.2dB/Hz and the total harmonic distortion have been found 75.4865dB with 6666H control word. The phase noise in proposed DCO design is -179.4dB/Hz at a frequency of 1.7324GHz.
Nozzle assembly for an earth boring drill bit
Energy Technology Data Exchange (ETDEWEB)
Madigan, J. A.
1985-09-24
A nozzle assembly for an earth boring drill bit of the type adapted to receive drilling fluid under pressure and having a nozzle bore in the bottom thereof positioned closely adjacent the well bore bottom when the bit is in engagement therewith with the bore having inner and outer portions. The nozzle assembly comprises a generally cylindrical nozzle member of abrasion and erosion resistant material, selected from a plurality of such members, each being of the same outer diameter but having passaging therein of different cross-sectional area. The nozzle member is adapted to be fitted in the inner portion of the nozzle bore in sealing relationship therewith for forming a first seal for the nozzle assembly. The nozzle assembly further comprises a locknut, separate from the nozzle member, for detachbably securing the nozzle member in the nozzle bore, formed at least in part of an abrasion and erosion resistant material. The locknut has a threaded side wall engageable with the outer portion of the nozzle bore, and an aperture therethrough for enabling a stream of drilling fluid from the nozzle member to flow therethrough and being so configured in section as to receive a tool for turning the lockout to install it in and remove it from the nozzle bore.
A per-pixel Log2ADC for high dynamic range, 1000FPS digital focal plane arrays (DFPA)
Petilli, Eugene
2016-09-01
Intrinsix has developed a Digital Focal Plane Array (DFPA) architecture based on a novel piecewise linear Log2 ADC (LADC) with "lossless" analog compression which enables ultra-high dynamic range ROICs that use less power than other extended dynamic range technologies. The LADC provides dynamic range of 126dB with a constant 75dB SNR over the entire frame. The companding 13bit mantissa, 3bit radix per pixel LADCs compress the 21bit signals into efficient 16 bit data words. The Read Out IC (ROIC) is compatible with most IR and LWIR detectors including two-color SLS (photodiode) and uBolometers. The DFPA architecture leverages two (staggered frame prime and redundant) MIPI CSI-3 interfaces to achieve full HD DFPA at 1000 frames/sec; an equivalent uncompressed data rate of 100Gb/sec. The LADC uses direct injection into a moderate sized integrating capacitor and several comparators create a stream of multi-bit data values. These values are accumulated in an SRAM based log2ALU and the radix of the ALU is combined with the data to generate a feedback current to the integrating capacitor, closing the delta loop. The integration time and a single pole low pass IIR filter are configurable using control signals to the log2ALU. The feedback current is at least partially generated using PWM for high linearity.
Pegueroles, Josep R.; Alins, Juan J.; de la Cruz, Luis J.; Mata, Jorge
2001-07-01
MPEG family codecs generate variable-bit-rate (VBR) compressed video with significant multiple-time-scale bit rate variability. Smoothing techniques remove the periodic fluctuations generated by the codification modes. However, global efficiency concerning network resource allocation remains low due to scene-time-scale variability. RCBR techniques provide suitable means to achieving higher efficiency. Among all RCBR techniques described in literature, 2RCBR mechanism seems to be especially suitable for video-on demand. The method takes advantage of the knowledge of the stored video to calculate the renegotiation intervals and of the client buffer memory to perform work-ahead buffering techniques. 2RCBR achieves 100% bandwidth global efficiency with only two renegotiation levels. The algorithm is based on the study of the second derivative of the cumulative video sequence to find out sharp-sloped inflection points that point out changes in the scene complexity. Due to its nature, 2RCBR becomes very adequate to deliver MPEG2 scalable sequences into the network cause it can assure a constant bit rate to the base MPEG2 layer and use the higher rate intervals to deliver the enhanced MPEG2 layer. However, slight changes in the algorithm parameters must be introduced to attain an optimal behavior. This is verified by means of simulations on MPEG2 video patterns.
Rate Distortion Analysis and Bit Allocation Scheme for Wavelet Lifting-Based Multiview Image Coding
Lasang, Pongsak; Kumwilaisak, Wuttipong
2009-12-01
This paper studies the distortion and the model-based bit allocation scheme of wavelet lifting-based multiview image coding. Redundancies among image views are removed by disparity-compensated wavelet lifting (DCWL). The distortion prediction of the low-pass and high-pass subbands of each image view from the DCWL process is analyzed. The derived distortion is used with different rate distortion models in the bit allocation of multiview images. Rate distortion models including power model, exponential model, and the proposed combining the power and exponential models are studied. The proposed rate distortion model exploits the accuracy of both power and exponential models in a wide range of target bit rates. Then, low-pass and high-pass subbands are compressed by SPIHT (Set Partitioning in Hierarchical Trees) with a bit allocation solution. We verify the derived distortion and the bit allocation with several sets of multiview images. The results show that the bit allocation solution based on the derived distortion and our bit allocation scheme provide closer results to those of the exhaustive search method in both allocated bits and peak-signal-to-noise ratio (PSNR). It also outperforms the uniform bit allocation and uniform bit allocation with normalized energy in the order of 1.7-2 and 0.3-1.4 dB, respectively.
Energy Technology Data Exchange (ETDEWEB)
Tojo, K.; Kurosawa, M.; Oka, K.; Higuchi, T. [The University of Tokyo, Tokyo (Japan)
1998-05-01
The application of single-bit digital signal processing to mechanical control system has already been proposed by the authors. Multi-bit A/D converter has been improved to the high level. But it is difficult to make more high resolution A/D by latest semiconductor technologies. There is single-bit digital signal which is generated by a delta-sigma modulator. Single-bit digital signal has small quantized error around low frequency. Then with this single-bit digital signal processing, high resolution on controlling such a narrow band width mechanical system will be realized. In this paper, resolution of analog, multi-bit and single-bit control systems are estimated with simulation. According to simulations` results, single-bit control system has higher resolution than multi-bit system in the condition of equal bit rate. 5 refs., 17 figs., 1 tab.
Zhou, Zhimin (Inventor); Pain, Bedabrata (Inventor)
1999-01-01
An analog-to-digital converter for on-chip focal-plane image sensor applications. The analog-to-digital converter utilizes a single charge integrating amplifier in a charge balancing architecture to implement successive approximation analog-to-digital conversion. This design requires minimal chip area and has high speed and low power dissipation for operation in the 2-10 bit range. The invention is particularly well suited to CMOS on-chip applications requiring many analog-to-digital converters, such as column-parallel focal-plane architectures.
Directory of Open Access Journals (Sweden)
Mohamad Ali Sadikin
2016-10-01
Full Text Available This research addresses the implementation of encryption and digital signature technique for electronic health record to prevent cybercrime such as robbery, modification and unauthorised access. In this research, RSA 2048-bit algorithm, AES 256-bit and SHA 256 will be implemented in Java programming language. Secure Electronic Health Record Information (SEHR application design is intended to combine given services, such as confidentiality, integrity, authentication, and nonrepudiation. Cryptography is used to ensure the file records and electronic documents for detailed information on the medical past, present and future forecasts that have been given only to the intended patients. The document will be encrypted using an encryption algorithm based on NIST Standard. In the application, there are two schemes, namely the protection and verification scheme. This research uses black-box testing and whitebox testing to test the software input, output, and code without testing the process and design that occurs in the system.We demonstrated the implementation of cryptography in SEHR. The implementation of encryption and digital signature in this research can prevent archive thievery.
A single channel, 6-bit 410-MS/s 3bits/stage asynchronous SAR ADC based on resistive DAC
Xue, Han; Qi, Wei; Huazhong, Yang; Hui, Wang
2015-05-01
This paper presents a single channel, low power 6-bit 410-MS/s asynchronous successive approximation register analog-to-digital converter (SAR ADC) for ultrawide bandwidth (UWB) communication, prototyped in a SMIC 65-nm process. Based on the 3 bits/stage structure, resistive DAC, and the modified asynchronous successive approximation register control logic, the proposed ADC attains a peak spurious-free dynamic range (SFDR) of 41.95 dB, and a signal-to-noise and distortion ratio (SNDR) of 28.52 dB for 370 MS/s. At the sampling rate of 410 MS/s, this design still performs well with a 40.71-dB SFDR and 30.02-dB SNDR. A four-input dynamic comparator is designed so as to decrease the power consumption. The measurement results indicate that this SAR ADC consumes 2.03 mW, corresponding to a figure of merit of 189.17 fJ/step at 410 MS/s. Project supported by the National Science Foundation for Young Scientists of China (No. 61306029) and the National High Technology Research and Development Program of China (No. 2013AA014103).
Directory of Open Access Journals (Sweden)
Otto Bachmann
1984-01-01
Full Text Available In this paper we continue the study of projective planes which admit collineation groups of low rank (Kallaher [1] and Bachmann [2,3]. A rank 5 collineation group of a projective plane ℙ of order n≠3 is proved to be flag-transitive. As in the rank 3 and rank 4 case this implies that is ℙ not desarguesian and that n is (a prime power of the form m4 if m is odd and n=m2 with m≡0mod4 if n is even. Our proof relies on the classification of all doubly transitive groups of finite degree (which follows from the classification of all finite simple groups.
Hydrodynamics of planing monohull watercraft
Vorus, William S
2017-01-01
This book addresses the principles involved in the design and engineering of planing monohull power boats, with an emphasis on the theoretical fundamentals that readers need in order to be fully functional in marine design and engineering. Author William Vorus focuses on three topics: boat resistance, seaway response, and propulsion and explains the physical principles, mathematical details, and theoretical details that support physical understanding. In particular, he explains the approximations and simplifications in mathematics that lead to success in the applications of planing craft design engineering, and begins with the simplest configuration that embodies the basic physics. He leads readers, step-by-step, through the physical complications that occur, leading to a useful working knowledge of marine design and engineering. Included in the book are a wealth of examples that exemplify some of the most important naval architecture and marine engineering problems that challenge many of today’s engineers.
Forgács, Péter; Romańczukiewicz, Tomasz
2013-01-01
It is shown that in a large class of systems plane waves can act as tractor beams: i.e., an incident plane wave can exert a pulling force on the scatterer. The underlying physical mechanism for the pulling force is due to the sufficiently strong scattering of the incoming wave into another mode having a larger wave number, in which case excess momentum is created behind the scatterer. Such a tractor beam or negative radiation pressure effect arises naturally in systems where the coupling between the scattering channels is due to Aharonov-Bohm (AB) gauge potentials. It is demonstrated that this effect is also present if the AB potential is an induced, ("artificial") gauge potential such as the one found in J. March-Russell, J. Preskill, F. Wilczek, Phys. Rev. Lett. 58 2567 (1992).
Eight plane IPND mechanical testing.
Energy Technology Data Exchange (ETDEWEB)
Zhao, A.; Guarino, V.; Wood, K.; Nephew, T.; Ayres, D.; Lee, A.; High Energy Physics; FNAL
2008-03-18
A mechanical test of an 8 plane IPND mechanical prototype, which was constructed using extrusions from the testing/tryout of the 16 cell prototype extrusion die in Argonne National Laboratory, was conducted. There were 4 vertical and 4 horizontal planes in this 8 plane IPND prototype. Each vertical plane had four 16 cell extrusions, while each horizontal plane had six 16 cell extrusions. Each plane was glued together using the formulation of Devcon adhesive, Devcon 60. The vertical extrusions used in the vertical planes shares the same dimensions as the horizontal extrusions in the horizontal planes with the average web thickness of 2.1 mm and the average wall thickness of 3.1 mm. This mechanical prototype was constructed with end-seals on the both ends of the vertical extrusions. The gaps were filled with epoxy between extrusions and end-seals. The overall dimension of IPND is 154.8 by 103.1 by 21.7 inches with the weight of approximately 1200 kg, as shown in a figure. Two similar mechanical tests of 3 layer and 11 layer prototypes have been done in order to evaluate the strength of the adhesive joint between extrusions in the NOvA detector. The test showed that the IPND prototype was able to sustain under the loading of weight of itself and scintillator. Two FEA models were built to verify the measurement data from the test. The prediction from FEA slice model seems correlated reasonably well to the test result, even under a 'rough' estimated condition for the wall thickness (from an untuned die) and an unknown property of 'garage type' extrusion. A full size of FEA 3-D model also agrees very well with the test data from strain gage readings. It is worthy to point out that the stress distribution of the structure is predominantly determined by the internal pressure, while the buckling stability relies more on the loading weight from the extrusions themselves and scintillate. Results of conducted internal pressure tests, including 3- cell, 11
Rate control algorithm based on frame complexity estimation for MVC
Yan, Tao; An, Ping; Shen, Liquan; Zhang, Zhaoyang
2010-07-01
Rate control has not been well studied for multi-view video coding (MVC). In this paper, we propose an efficient rate control algorithm for MVC by improving the quadratic rate-distortion (R-D) model, which reasonably allocate bit-rate among views based on correlation analysis. The proposed algorithm consists of four levels for rate bits control more accurately, of which the frame layer allocates bits according to frame complexity and temporal activity. Extensive experiments show that the proposed algorithm can efficiently implement bit allocation and rate control according to coding parameters.
DEFF Research Database (Denmark)
Rathkjen, Arne
A state of plane stress is illustrated by means of two families of curves, each family representing constant values of a derivative of Airy's stress function. The two families of curves form a map giving in the first place an overall picture of regions of high and low stress, and in the second...... place, the map comprises a complete graphic representation of the stress at any point....
Experimental research on characteristics of hole reaming and side cutting of one-cone bits
Institute of Scientific and Technical Information of China (English)
Yu Kai'an
2008-01-01
The hole reaming and side cutting characteristics of offset one-cone bit and conventional one-cone bit were investigated on simulated drilling experimental equipment.The borehole diameter was a little larger than the bit diameter due to side force.However,the reaming effect was not very apparent,whether drilling with an offset or conventional one-cone bit.The side cutting displacement increased gradually with increasing depth of drilling and side force.The side cutting displacement of offset one-cone bits was larger than that of conventional ones under the same conditions of weight-on-bit(WOB),rotary speed,side force and borehole depth.
Yang, Aiying; Li, Xiangming; Jiang, Tao
2012-04-23
Combination of overlapping pulse position modulation and pulse width modulation at the transmitter and grouped bit-flipping algorithm for low-density parity-check decoding at the receiver are proposed for visible Light Emitting Diode (LED) indoor communication system in this paper. The results demonstrate that, with the same Photodetector, the bit rate can be increased and the performance of the communication system can be improved by the scheme we proposed. Compared with the standard bit-flipping algorithm, the grouped bit-flipping algorithm can achieve more than 2.0 dB coding gain at bit error rate of 10-5. By optimizing the encoding of overlapping pulse position modulation and pulse width modulation symbol, the performance can be further improved. It is reasonably expected that the bit rate can be upgraded to 400 Mbit/s with a single available LED, thus transmission rate beyond 1 Gbit/s is foreseen by RGB LEDs.
Why Quantum Bit Commitment And Ideal Quantum Coin Tossing Are Impossible
Lo, H K
1998-01-01
There had been well known claims of unconditionally secure quantum protocols for bit commitment. However, we, and independently Mayers, showed that all proposed quantum bit commitment schemes are, in principle, insecure because the sender, Alice, can almost always cheat successfully by using an Einstein-Podolsky-Rosen (EPR) type of attack and delaying her measurements. One might wonder if secure quantum bit commitment protocols exist at all. We answer this question by showing that the same type of attack by Alice will, in principle, break any bit commitment scheme. The cheating strategy generally requires a quantum computer. We emphasize the generality of this ``no-go theorem'': Unconditionally secure bit commitment schemes based on quantum mechanics---fully quantum, classical or quantum but with measurements---are all ruled out by this result. Since bit commitment is a useful primitive for building up more sophisticated protocols such as zero-knowledge proofs, our results cast very serious doubt on the secur...
Design and Demonstration of a 30 GHz 16-bit Superconductor RSFQ Microprocessor
2015-03-10
for Public Release; Distribution Unlimited Final Report: Design and Demonstration of a 30 GHz 16-bit Superconductor RSFQ Microprocessor The views...Demonstration of a 30 GHz 16-bit Superconductor RSFQ Microprocessor Report Title The major objective of the project was to design and demonstrate operation...25, no.3, pp.1-8, June 2015. Technology Transfer Final Report: Design and Demonstration of a 30 GHz 16‐bit Superconductor RSFQ Microprocessor
Computer-Aided Design for Built-In-Test (CADBIT) - BIT Library. Volume 2
1989-10-01
TECHNIQUE: ON-BOARD RONI CATEGORY: LONG TUTORIA \\L PAG E 5 of 14I SUBCATEGORY: BIT TECHNIQUE ATTRIBUTES DATA TYPE: TEXT El LIST E] TABLE [ GRAPHIC E...SHIFT REGISTER (MISR) CATEGORY: LONG TUTORIA -L PAGE i Of 13 SUBCATEGORY: BIT TECH-{MQUE ATTRIBUTES DATA TYPE: TEXT LIST El TABLE GRAPHIC E EQUATIONS...ELEMENT DATA SHEET BIT TECHNIQUE: UTILIZING REDUNDANCY CATEGORY: LONG TUTORIA L PAGE 9 of 10 SUBCATEGORY: PARTS DATA TABLE DATA TYPE: TEXT F1 UST C3
The Anoikis Effector Bit1 Displays Tumor Suppressive Function in Lung Cancer Cells
Xin Yao; Scott Jennings; Shubha Kale Ireland; Tri Pham; Brandi Temple; Mya Davis; Renwei Chen; Ian Davenport; Hector Biliran
2014-01-01
The mitochondrial Bit1 (Bcl-2 inhibitor of transcription 1) protein is a part of an apoptotic pathway that is uniquely regulated by integrin-mediated attachment. As an anoikis effector, Bit1 is released into the cytoplasm following loss of cell attachment and induces a caspase-independent form of apoptosis. Considering that anoikis resistance is a critical determinant of transformation, we hypothesized that cancer cells may circumvent the Bit1 apoptotic pathway to attain anchorage-independenc...
Contador asincrónico de cuatro bits
Directory of Open Access Journals (Sweden)
Iván Jaramillo J.
2011-01-01
Full Text Available Este artículo describe el diseño e implementación del conttulor asincrónico de cuatro bits, realizado a partir de experiencias académicas en la Universidad Nacional de Colombia. Primero se menciona la estructura del contador, al igual que la caracterización de las celdas básicas (con base en las cuales se hizo este proyecto, y se muestran los resultados de la simulación eléctrica. Después, se describen las pruebas efectuadas al chip, y se hace una comparación entre estos datos experimentales y los obtenidos en la simulación.
Numerical optimization of writer geometries for bit patterned magnetic recording
Kovacs, A; Bance, S; Fischbacher, J; Gusenbauer, M; Reichel, F; Exl, L; Schrefl, T; Schabes, M E
2015-01-01
A fully-automated pole-tip shape optimization tool, involving write head geometry construction, meshing, micromagnetic simulation and evaluation, is presented. Optimizations have been performed for three different writing schemes (centered, staggered and shingled) for an underlying bit patterned media with an areal density of 2.12 Tdots/in$^2$ . Optimizations were performed for a single-phase media with 10 nm thickness and a mag spacing of 8 nm. From the computed write field and its gradient and the minimum energy barrier during writing for islands on the adjacent track, the overall write error rate is computed. The overall write errors are 0.7, 0.08, and 2.8 x 10$^{-5}$ for centered writing, staggered writing, and shingled writing.
An algorithm for redundant binary bit-pipelined rational arithmetic
Energy Technology Data Exchange (ETDEWEB)
Kornerup, P. (Dept. of Mathematics and Computer Science, Odense Universitet, Odense (DK)); Matula, D.W. (Dept. of Computer Science and Engineering, Southern Methodist Univ., Dallas, TX (US))
1990-08-01
The authors introduce a redundant binary representation of the rationals and an associated algorithm for computing the sum, difference, product, quotient, and other useful functions of two rational operands, employing our representation. The authors' algorithm extends Gosper's partial quotient arithmetic algorithm and allows the design of an on-line arithmetic unit with computations granularized at the signed bit level. Each input or output port can independently be set to receive/produce operands/result in either binary radix or our binary rational representation. The authors investigate by simulation the interconnection of several such units for the parallel computation of more complicated expressions in a tree-pipelined manner, with particular regards to measuring individual and compound on-line delays.
The Application of Bit Slice Design to Digital Image Processing.
1986-09-01
AM2910 INSTR H#E ;continue RESULTINO MICROWORD: 0043 3FOF FOIE (X-1) CO IMENTS: Bits L15-47 declare the source registers to be in the pipeline...3FFF CO24 ;PUSH ADO. ON STACK, LO CTR w/02 0101 Oe4F 3F03 F14E ;MEMORY -) R4 0102 0043 3FOF FOIE ;RI-4 -, RI 0103 084F 3FO3 F13E ;MEMORY - R3 0101t 0043...3FOF F34E ;R3*R9 -> R4 .O S 0043 3FCF F21E ;R1-2 - RI S0105 084F 3F03 F13E ;MEMORY -, R3 0107 0043 3FCF F34E ;R3 R4 -) R4 0108 0043 3F0F FOIE ;RI4
Novel Parity-Preserving Designs of Reversible 4-Bit Comparator
Qi, Xue-mei; Chen, Fu-long; Wang, Hong-tao; Sun, Yun-xiang; Guo, Liang-min
2014-04-01
Reversible logic has attracted much attention in recent years especially when the calculation with minimum energy consumption is considered. This paper presents two novel approaches for designing reversible 4-bit comparator based on parity-preserving gates, which can detect any fault that affects no more than a single logic signal. In order to construct the comparator, three variable EX-OR gate (TVG), comparator gate (CPG), four variable EX-OR gate block (FVGB) and comparator gate block (CPGB) are designed, and they are parity-preserving and reversible. Their quantum equivalent implementations are also proposed. The design of two comparator circuits is completed by using existing reversible gates and the above new reversible circuits. All these comparators have been modeled and verified in Verilog hardware description language (Verilog HDL). The Quartus II simulation results indicate that their circuits' logic structures are correct. The comparative results are presented in terms of quantum cost, delay and garbage outputs.
A Fast Dynamic 64-bit Comparator with Small Transistor Count
Directory of Open Access Journals (Sweden)
Chua-Chin Wang
2002-01-01
Full Text Available In this paper, we propose a 64-bit fast dynamic CMOS comparator with small transistor count. Major features of the proposed comparator are the rearrangement and re-ordering of transistors in the evaluation block of a dynamic cell, and the insertion of a weak n feedback inverter, which helps the pull-down operation to ground. The simulation results given by pre-layout tools, e.g. HSPICE, and post-layout tools, e.g. TimeMill, reveal that the delay is around 2.5 ns while the operating clock rate reaches 100 MHz. A physical chip is fabricated to verify the correctness of our design by using UMC (United Microelectronics Company 0.5 μm (2P2M technology.
Delay Efficient 32-Bit Carry-Skip Adder
Directory of Open Access Journals (Sweden)
Yu Shen Lin
2008-01-01
Full Text Available The design of a 32-bit carry-skip adder to achieve minimum delay is presented in this paper. A fast carry look-ahead logic using group generate and group propagate functions is used to speed up the performance of multiple stages of ripple carry adders. The group generate and group propagate functions are generated in parallel with the carry generation for each block. The optimum block sizes are decided by considering the critical path into account. The new architecture delivers the sum and carry outputs in lesser unit delays than existing carry-skip adders. The adder is implemented in 0.25 m CMOS technology at 3.3 V. The critical delay for the proposed adder is 3.4 nanoseconds. The simulation results show that the proposed adder is 18% faster than the current fastest carry-skip adder.
Design and Implementation of an Efficient 64 bit MAC
Directory of Open Access Journals (Sweden)
Mohammad Shabber Hasan Khan
2015-08-01
Full Text Available The design of optimized 64 bit multiplier and accumulator (MAC unit is implemented in this paper. MAC unit plays major role in many of the digital signal processing (DSP applications. The MAC unit is designed with the combinations of multipliers and adders. In the proposed method MAC unit is implemented using Vedic multiplier and the adder is done with ripple carry adder .The components are reduced by implementing Vedic multiplier using the techniques of Vedic mathematics that have been modified to improve performance. a high speed processor depends significantly on the multiplier as it is one of the key hardware blocks in most digital signal processing systems as well as in general processors. The area is optimized effectively using Vedic multiplier .The total design implemented using Xilinx.
ALL OPTICAL 3-BIT SERIAL INPUT SHIFT REGISTER DESIGN
Directory of Open Access Journals (Sweden)
VIKRANT K SRIVASTAVA,
2010-08-01
Full Text Available In this Paper, we present all-optical shift Register logic with complete Boolean functionality as a representative circuit for modeling and optimization of monolithically integrated components. Proposed optical logic unit is based on nonlinear effects in semiconductor optical amplifiers (SOA. We show a strategy of optical pulse propagation in SOA based on coupled nonlinear equations describing XGM and FWM effects. These equations are first solved togenerate the pump, probe and conjugate pulses in a SOA. The pulse behavior are analyzed and applied to realize behavior of all-optical NAND gate. Next, the logic is used to implement All-Optical Flip-Flop logic, and its function is verified with the help of truth table. Finally with the help of three Flip Flop a 3-bit shift register is proposed. The full design is simple, compact, economical, thermally stable and integration capable.
Experimental approximation of the Jones polynomial with one quantum bit.
Passante, G; Moussa, O; Ryan, C A; Laflamme, R
2009-12-18
We present experimental results approximating the Jones polynomial using 4 qubits in a liquid state nuclear magnetic resonance quantum information processor. This is the first experimental implementation of a complete problem for the deterministic quantum computation with one quantum bit model of quantum computation, which uses a single qubit accompanied by a register of completely random states. The Jones polynomial is a knot invariant that is important not only to knot theory, but also to statistical mechanics and quantum field theory. The implemented algorithm is a modification of the algorithm developed by Shor and Jordan suitable for implementation in NMR. These experimental results show that for the restricted case of knots whose braid representations have four strands and exactly three crossings, identifying distinct knots is possible 91% of the time.
Building a spin quantum bit register using semiconductor nanowires.
Baugh, J; Fung, J S; Mracek, J; LaPierre, R R
2010-04-02
This paper reviews recent advances in engineering spin quantum bits (qubits) in semiconductor quantum dots and describes an approach based on top-gated semiconductor nanowire devices. Fast electrical single-spin manipulation is achievable, in principle, using the spin-orbit interaction intrinsic to III-V materials, such as InAs, in concert with AC electric fields. Combined with sub-nanosecond gate control of the nearest-neighbor exchange interaction and spin readout by spin-to-charge conversion, a fully electrical solid-state quantum processor is within reach. We outline strategies for spin manipulation, robust readout and mitigation of decoherence due to nuclear fields that, when combined in a single device, should give a viable multi-qubit testbed and a building block for larger scale quantum devices.
Geneva University - Superconducting flux quantum bits: fabricated quantum objects
2007-01-01
Ecole de physique Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 Tél: (022) 379 62 73 Fax: (022) 379 69 92 Lundi 29 janvier 2007 COLLOQUE DE LA SECTION DE PHYSIQUE 17 heures - Auditoire Stueckelberg Superconducting flux quantum bits: fabricated quantum objects Prof. Hans Mooij / Kavli Institute of Nanoscience, Delft University of Technology The quantum conjugate variables of a superconductor are the charge or number of Cooper pairs, and the phase of the order parameter. In circuits that contain small Josephson junctions, these quantum properties can be brought forward. In Delft we study so-called flux qubits, superconducting rings that contain three small Josephson junctions. When a magnetic flux of half a flux quantum is applied to the loop, there are two states with opposite circulating current. For suitable junction parameters, a quantum superposition of those macroscopic states is possible. Transitions can be driven with resonant microwaves. These quantum ...
Distribution of digital games via BitTorrent
DEFF Research Database (Denmark)
Drachen, Anders; Bauer, Kevin; Veitch, Robert W. D.
2011-01-01
The practice of illegally copying and distributing digital games is at the heart of one of the most heated and divisive debates in the international games environment. Despite the substantial interest in game piracy, there is very little objective information available about its magnitude or its...... distribution across game titles and game genres. This paper presents the first large-scale, open-method analysis of the distribution of digital game titles, which was conducted by monitoring the BitTorrent peer-to-peer (P2P) file-sharing protocol. The sample includes 173 games and a collection period of three...... months from late 2010 to early 2011. With a total of 12.6 million unique peers identified, it is the largest examination of game piracy via P2P networks to date. The study provides findings that reveal the magnitude of game piracy, the time-frequency of game torrents, which genres that get pirated...
RELAY ASSISTED TRANSMISSSION WITH BIT-INTERLEAVED CODED MODULATION
Institute of Scientific and Technical Information of China (English)
Meng Qingmin; You Xiaohu; John Boyer
2006-01-01
We investigate an adaptive cooperative protocol in a Two-Hop-Relay (THR) wireless system that combines the following: (1) adaptive relaying based on repetition coding; (2) single or two transmit antennas and one receive antenna configurations for all nodes, each using high order constellation; (3) Bit-Interleaved Coded Modulation (BICM). We focus on a simple decoded relaying (i.e. no error correcting at a relay node)and simple signal quality thresholds for relaying. Then the impact of the two simple thresholds on the system performance is studied. Our results suggest that compared with the traditional scheme for direct transmission,the proposed scheme can increase average throughput in high spectral efficiency region with low implementation-cost at the relay.
El cuaderno de bitácora como proceso educativo
Comas, Karina; Morawicki, Marcos Kevin
2015-01-01
La ponencia “El cuaderno de Bitácora como proceso educativo” forma parte de un avance de investigación del Proyecto Acreditado “Anclajes institucionales de las políticas de formación de formadores en comunicación: Procesos y desarrollos”, dirigido por María Belén Fernández. Esta investigación aborda la temática de la formación permanente en comunicación estudiando para eso diversos anclajes institucionales sobre cómo se presenta la articulación entre el campo de comunicación/educación y las n...
Measurements of Aperture Averaging on Bit-Error-Rate
Bastin, Gary L.; Andrews, Larry C.; Phillips, Ronald L.; Nelson, Richard A.; Ferrell, Bobby A.; Borbath, Michael R.; Galus, Darren J.; Chin, Peter G.; Harris, William G.; Marin, Jose A.; Burdge, Geoffrey L.; Wayne, David; Pescatore, Robert
2005-01-01
We report on measurements made at the Shuttle Landing Facility (SLF) runway at Kennedy Space Center of receiver aperture averaging effects on a propagating optical Gaussian beam wave over a propagation path of 1,000 in. A commercially available instrument with both transmit and receive apertures was used to transmit a modulated laser beam operating at 1550 nm through a transmit aperture of 2.54 cm. An identical model of the same instrument was used as a receiver with a single aperture that was varied in size up to 20 cm to measure the effect of receiver aperture averaging on Bit Error Rate. Simultaneous measurements were also made with a scintillometer instrument and local weather station instruments to characterize atmospheric conditions along the propagation path during the experiments.
Diversity Analysis of Bit-Interleaved Coded Multiple Beamforming
Park, Hong Ju
2008-01-01
In this paper, diversity analysis of bit-interleaved coded multiple beamforming (BICMB) is extended to the case of general spatial interleavers, removing a condition on their previously known design criteria and quantifying the resulting diversity order. The diversity order is determined by a parameter Qmax which is inherited from the convolutional code and the spatial de-multiplexer used in BICMB. We introduce a method to find this parameter by employing a transfer function approach as in finding the weight spectrum of a convolutional code. By using this method, several Qmax's are shown and verified to be identical with the results from a computer searching program tracing paths on the trellis. The diversity analysis and the method to find the parameter are supported by simulation results.
Bit-Interleaved Coded Multiple Beamforming with Imperfect CSIT
Ayanoglu, Ersin Sengul Ender
2007-01-01
This paper addresses the performance of bit-interleaved coded multiple beamforming (BICMB) with imperfect knowledge of beamforming vectors. Various wireless standards become equivalent to BICMB when they are operated in beamforming mode. In BICMB, the invariance of the precoding matrix under an arbitrary unitary transform widely studied in the literature is not applicable. On the other hand, the optimum precoder and detector are not unique because of invariance under a diagonal unitary transform. We propose an optimal Euclidean distortion measure and a new linear detector. In addition, a new codebook design is proposed via the generalized Lloyd algorithm based on the new distortion measure. We provide simulation results demonstrating the performance improvement achieved with the proposed distortion measure and the linear detector.
Introducing the Intel i860 64-bit microprocessor
Energy Technology Data Exchange (ETDEWEB)
Kohn, L.; Margulis, N. (Intel Corp., Santa Clara, CA (USA))
1989-08-01
The development of a single-chip i860 CPU 64-bit, RISC-based microprocessor is reported in this article. It executes parallel instructions using mainframe and supercomputer architectural concepts. The authors designed the 1,000,000-transistor, 10 mm x 15 mm processor for balanced integer, floating-point, and graphics performance. To accommodate their performance goals, they divided the chip area evenly between blocks for integer operations, floating-point operations, and instruction and data cache memories. Inclusion of the RISC (reduced instruction set computing) core, floating-point units, and caches on one chip allowed design of wider internal buses, eliminated interchip communication over-head, and enabled higher performance. As a result, the i860 avoids off-chip delays and allows users to scale the clock beyond the current 33- and 40- MHz speeds. Applications described include workstations, minicomputers, application accelerators for existing processors, and parallel supercomputers.
Institute of Scientific and Technical Information of China (English)
Shuqing HAO; Hongwei HUANG; Kun YIN
2007-01-01
By simplifying the characters in the air reverse circulation bit interior fluid field, the authors used air dynamics and fluid mechanics to calculate the air distribution in the bit and obtained an equation of flow distribution with a unique resolution. This study will provide help for making certain the bit parameters of the bit structure effectively and study the air reverse circulation bit interior fluid field character deeply.
Proposed first-generation WSQ bit allocation procedure
Energy Technology Data Exchange (ETDEWEB)
Bradley, J.N.; Brislawn, C.M.
1993-09-08
The Wavelet/Scalar Quantization (WSQ) gray-scale fingerprint image compression algorithm involves a symmetric wavelet transform (SWT) image decomposition followed by uniform scalar quantization of each subband. The algorithm is adaptive insofar as the bin widths for the scalar quantizers are image-specific and are included in the compressed image format. Since the decoder requires only the actual bin width values -- but not the method by which they were computed -- the standard allows for future refinements of the WSQ algorithm by improving the method used to select the scalar quantizer bin widths. This report proposes a bit allocation procedure for use with the first-generation WSQ encoder. In previous work a specific formula is provided for the relative sizes of the scalar quantizer bin widths in terms of the variances of the SWT subbands. An explicit specification for the constant of proportionality, q, that determines the absolute bin widths was not given. The actual compression ratio produced by the WSQ algorithm will generally vary from image to image depending on the amount of coding gain obtained by the run-length and Huffman coding, stages of the algorithm, but testing performed by the FBI established that WSQ compression produces archival quality images at compression ratios of around 20 to 1. The bit allocation procedure described in this report possesses a control parameter, r, that can be set by the user to achieve a predetermined amount of lossy compression, effectively giving the user control over the amount of distortion introduced by quantization noise. The variability observed in final compression ratios is thus due only to differences in lossless coding gain from image to image, chiefly a result of the varying amounts of blank background surrounding the print area in the images. Experimental results are presented that demonstrate the proposed method`s effectiveness.
A pipelined 50-MHz CMOS 64-bit floating-point arithmetic processor
Energy Technology Data Exchange (ETDEWEB)
Benschneider, B.J.; Bowhill, W.J.; Cooper, E.M.; Gronowski, P.E.; Peng, V.; Pickholtz, J.D.; Samudrala, S. (Digital Equipment Corp., Hudson, MA (US)); Gavrielov, M.N. (LSI Logic Corp., Milpitas, CA (US)); Maheshwari, V.K. (AT and T Bell Labs., Allentown, PA (US))
1989-10-01
A 135 K transistor, uniformly pipelined 50-MHz CMOS 64-bit floating-point arithmetic processor chip is described. The execution unit is capable of sustaining pipelined performance of one 32-bit or 64-bit result every 20 ns for all operations except double-precision multiply (40 ns) and divide. The chip employs an exponent difference prediction scheme and a unified leading-one and sticky-bit computation logic for the addition (ADD) and subtraction (SUB) operations. A hardware multiplier using a radix-8 modified Booth algorithm and a divider using a radix-2 SRT algorithm ar used.
The Digital Agenda of Virtual Currencies. Can BitCoin Become a Global Currency?
KANCS D'ARTIS; CIAIAN PAVEL; MIROSLAVA Rajcaniova
2015-01-01
This paper identifies and analyzes BitCoin features which may facilitate Bitcoin to become a global currency, as well as characteristics which may impede the use of BitCoin as a medium of exchange, a unit of account and a store of value, and compares BitCoin with standard currencies with respect to the main functions of money. Among all analyzed BitCoin features, the extreme price volatility stands out most clearly compared to standard currencies. In order to understand the reasons for such e...
14-bit pipeline-SAR ADC for image sensor readout circuits
Wang, Gengyun; Peng, Can; Liu, Tianzhao; Ma, Cheng; Ding, Ning; Chang, Yuchun
2015-03-01
A two stage 14bit pipeline-SAR analog-to-digital converter includes a 5.5bit zero-crossing MDAC and a 9bit asynchronous SAR ADC for image sensor readout circuits built in 0.18um CMOS process is described with low power dissipation as well as small chip area. In this design, we employ comparators instead of high gain and high bandwidth amplifier, which consumes as low as 20mW of power to achieve the sampling rate of 40MSps and 14bit resolution.
The Digital Agenda of Virtual Currencies. Can BitCoin Become a Global Currency?
KANCS D'ARTIS; CIAIAN PAVEL; MIROSLAVA RAJCANIOVA
2015-01-01
This paper identifies and analyzes BitCoin features which may facilitate Bitcoin to become a global currency, as well as characteristics which may impede the use of BitCoin as a medium of exchange, a unit of account and a store of value, and compares BitCoin with standard currencies with respect to the main functions of money. Among all analyzed BitCoin features, the extreme price volatility stands out most clearly compared to standard currencies. In order to understand the reasons for such e...
Optimization of Mapping Rule of Bit-Interleaved Turbo Coded Modulation with 16QAM
Institute of Scientific and Technical Information of China (English)
FEI Ze-song; YANG Yu; LIU Lin-nan; KUANG Jing-ming
2005-01-01
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation.
A Novel Nondestructive Bit-Line Discharging Scheme for Deep Submicrometer STT-RAM
DEFF Research Database (Denmark)
Zeinali, Behzad; Madsen, Jens Kargaard; Raghavan, Praveen
. In this paper, we propose a novel non-destructive self-reference sensing scheme for STT-RAM. The proposed technique overcomes the large bit-to-bit variation of MTJ resistance. In the proposed scheme, the stored value in the STTRAM cell preserves, hence, the long write-back operation is eliminated. Besides......, the sensing scheme is accomplished in one step. In this scheme, the Bit-Line is pre-charged and then discharged during read operation. The MTJ resistance state can be found by comparing the time constant of discharging. The simulation results show the overall sensing time is 4 ns when the Bit-Line capacitance...
Two-bit quantum random number generator based on photon-number-resolving detection
Jian, Yi; Ren, Min; Wu, E.; Wu, Guang; Zeng, Heping
2011-07-01
Here we present a new fast two-bit quantum random number generator based on the intrinsic randomness of the quantum physical phenomenon of photon statistics of coherent light source. Two-bit random numbers were generated according to the number of detected photons in each light pulse by a photon-number-resolving detector. Poissonian photon statistics of the coherent light source guaranteed the complete randomness of the bit sequences. Multi-bit true random numbers were generated for the first time based on the multi-photon events from a coherent light source.
Hypersonic characteristics of an advanced aerospace plane
Mccandless, R. S.; Cruz, C. I.
1985-01-01
A series of hypersonic wind-tunnel tests have been conducted in the NASA Langley Hypersonic Facilities Complex to obtain the static longitudinal and lateral-directional aerodynamic characteristics of an advanced aerospace plane. Data were obtained at 0 to 20 deg angles of attack and -3 to 3 deg angles of sideslip at Mach numbers of 6 and 10 in air and 20 in helium. Results show that stable trim capability exists at angles of attack near maximum lift-drag ratio (L/D). Both performance and stability exhibited some Mach number dependency. The vehicle was longitudinally unstable at low angles of attack but stable at angles of attack near and above maximum L/D. It was directionally unstable with positive dihedral effect. The rudder showed an inability to provide lateral-directional control, and removing the vertical tail resulted in increased directional instability. Analytical predictions of the static longitudinal aerodynamic coefficients gave relatively good comparisons with the experimental data.
Crisis bifurcations in plane Poiseuille flow.
Zammert, Stefan; Eckhardt, Bruno
2015-04-01
Many shear flows follow a route to turbulence that has striking similarities to bifurcation scenarios in low-dimensional dynamical systems. Among the bifurcations that appear, crisis bifurcations are important because they cause global transitions between open and closed attractors, or indicate drastic increases in the range of the state space that is covered by the dynamics. We here study exterior and interior crisis bifurcations in direct numerical simulations of transitional plane Poiseuille flow in a mirror-symmetric subspace. We trace the state space dynamics from the appearance of the first three-dimensional exact coherent structures to the transition from an attractor to a chaotic saddle in an exterior crisis. For intermediate Reynolds numbers, the attractor undergoes several interior crises, in which new states appear and intermittent behavior can be observed. The bifurcations contribute to increasing the complexity of the dynamics and to a more dense coverage of state space.
Directory of Open Access Journals (Sweden)
Lei Sun
2014-01-01
Full Text Available This Letter proposes a least significant bit-down switching scheme in the capacitive digital-to-analogue converters (CDACs of successive approximation register analog-to-digital converter (ADC. Under the same unit capacitor, the chip area and the switching energy are halved without increasing the complexity of logic circuits. Compared with conventional CDAC, when it is applied to one of the most efficient switching schemes, V(cm-based structure, it achieves 93% less switching energy and 75% less chip area with the same differential non linearity (DNL/integral non linearity (INL performance.
Bit patterned media with composite structure for microwave assisted magnetic recording
Eibagi, Nasim
Patterned magnetic nano-structures are under extensive research due to their interesting emergent physics and promising applications in high-density magnetic data storage, through magnetic logic to bio-magnetic functionality. Bit-patterned media is an example of such structures which is a leading candidate to reach magnetic densities which cannot be achieved by conventional magnetic media. Patterned arrays of complex heterostructures such as exchange-coupled composites are studied in this thesis as a potential for next generation of magnetic recording media. Exchange-coupled composites have shown new functionality and performance advantages in magnetic recording and bit patterned media provide unique capability to implement such architectures. Due to unique resonant properties of such structures, their possible application in spin transfer torque memory and microwave assisted switching is also studied. This dissertation is divided into seven chapters. The first chapter covers the history of magnetic recording, the need to increase magnetic storage density, and the challenges in the field. The second chapter introduces basic concepts of magnetism. The third chapter explains the fabrication methods for thin films and various lithographic techniques that were used to pattern the devices under study for this thesis. The fourth chapter introduces the exchanged coupled system with the structure of [Co/Pd] / Fe / [Co/Pd], where the thickness of Fe is varied, and presents the magnetic properties of such structures using conventional magnetometers. The fifth chapter goes beyond what is learned in the fourth chapter and utilizes polarized neutron reflectometry to study the vertical exchange coupling and reversal mechanism in patterned structures with such structure. The sixth chapter explores the dynamic properties of the patterned samples, and their reversal mechanism under microwave field. The final chapter summarizes the results and describes the prospects for future
Fisher, Stephen D
1999-01-01
The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic
EnhancedBit: Unleashing the potential of the unchoking policy in the BitTorrent protocol
Atlidakis, V; Delis, A
2014-01-01
In this paper, we propose a modification to the BitTorrent protocol related to its peer unchoking policy. In particular, we apply a novel optimistic unchoking approach that improves the quality of inter-connections amongst peers, i.e., increases the number of directly-connected and interested-in-cooperation peers without penalizing underutilized and/or idle peers. Our optimistic unchoking policy takes into consideration the number of clients currently interested in downloading from a peer that is to be unchoked. Our conjecture is that peers having few clients interested in downloading data from them, should be favored with optimistic unchoke intervals. This enables the peers in question to receive data since they become unchoked faster and in turn, they will trigger the interest of additional clients. In contrast, peers with plenty of "interested" clients should enjoy a lower priority to be selected as planned optimistic unchoked, since these peers likely have enough data to forward; nevertheless, they receiv...
SNAP Satellite Focal Plane Development
Energy Technology Data Exchange (ETDEWEB)
Bebek, C.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Baltay, C.; Barrelet, E.; Basa, S.; Bercovitz, J.; Bergstrom, L.; Berstein, G.P.; Bester, M.; Bohlin, R.; Bonissent, A.; Bower, C.; Campbell, M.; Carithers, W.; Commins, E.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, A.; Ellis, R.; Emmett, W.; Eriksson, M.; Fouchez,D.; Fruchter, A.; Genat, J-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Heetderks, H.; Holland, S.; Huterer, D.; Johnson, W.; Kadel, R.; Karcher,A.; Kim, A.; Kolbe, W.; Lafever, R.; Lamoureaux, J.; Lampton, M.; Lefevre, O.; Levi, M.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Mazure, A.; McKay, T.; McKee, S.; Miquel, R.; Morgan, N.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Roe, N.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Prieto, E.; Rabinowitz,D.; Refregier, A.; Rhodes, J.; Schubnell, M.; Sholl, M.; Smadja, G.; Smith, R.; Smoot, G.; Snyder, J.; Spadafora, A.; Szymkowiak, A.; Tarle,G.; Taylor, K.; Tilquin, A.; Tomasch, A.; Vincent, D.; von der Lippe, H.; Walder, J-P.; Wang, G.
2003-07-07
The proposed SuperNova/Acceleration Probe (SNAP) mission will have a two-meter class telescope delivering diffraction-limited images to an instrumented 0.7 square degree field in the visible and near-infrared wavelength regime. The requirements for the instrument suite and the present configuration of the focal plane concept are presented. A two year R&D phase, largely supported by the Department of Energy, is just beginning. We describe the development activities that are taking place to advance our preparedness for mission proposal in the areas of detectors and electronics.
On free fermions and plane partitions
Foda, O; Zuparic, M
2008-01-01
We use free fermion methods to re-derive a result of Okounkov and Reshetikhin relating charged fermions to random plane partitions, and to extend it to relate neutral fermions to strict plane partitions.
Field Study of Drilling Bits Performance Optimization Using a Computer Model.
Directory of Open Access Journals (Sweden)
Oriji, A. Boniface
2015-03-01
Full Text Available One of the major problems facing drilling operations is the performance of the drilling Bits. The ability of the Bit to crush the rock and the removal of the crushed rock from the wellbore effectively. It is necessary to understand the fundamental difference in Bit design for different rock textures because many variables tend to affect Bit optimization, particularly the type of formations, economics and Bit selection. However, the cost of drilling a well has a considerable effect on the selection and the design of a particular Bit, therefore this paper focuses on the development of a model that will predict future Bit performance and optimization for actual well design and construction. The variables to optimize Bit performance provide means of handling cost estimation hence the model becomes more realistic and dynamic in its application. The input variables and control factors for this model are stretched to minimize cost and maximize performance. The cost per foot and the break even calculations were done using data from the reference well X14 and also the evaluation well X35 from a field-X in the Niger Delta region. A Visual Basic dot Net program model was developed, tested and validated with the real field data to know its accuracy. The model interface shows the detailed application of the Bits in validating the data to provide the equivalent results for the five different Bits. Each set of the Bit record was ran separately on the software and the results for each application developed for comparison. In the software, data application were grouped into two distinct methods namely; rentals method and historical method. Under the rentals method, data were uploaded into the software and ran to generate results while the historical method was basically used for model prediction. The breakeven analysis provided a technique for calculating the performance required for an alternative Bit type to match the cost per foot of the current Bit. Based on
Efficient Circuit Configuration for Enhancing Resolution of 8-bit flash Analog to Digital Convertor
Directory of Open Access Journals (Sweden)
Gururaj Balikatti
2012-11-01
Full Text Available The need constantly exists for converters with higher resolution, faster conversion speeds and lower power dissipation. High speed analog to digital converters (ADCs have been based on flash architecture, because all comparators sample the analog input voltage simultaneously, this ADC is thus inherently fast. Unfortunately flash ADC requires 2N - 1 comparators to convert N bit digital code from an analog sample. This makes flash ADCs unsuitable for high resolution applications. The focus of this paper is on efficient circuit configuration to enhance resolution of available 8-bit flash ADC, while maintaining number of comparators only 256 for 12 bit conversion. This technique optimizes the number of comparator requirements. In this approach, an 8-bit flash ADC partitions the analog input range into 256 quantization cells, separated by 255 boundary points. An 8-bit binary code 00000000 to 11111111 is assigned to each cell. The Microcontroller decides within which cell the input sample lies and assigns a 12-bit binary center code 000000000000 to 111111111111 according to the cell value. The exact 12-bit digital code is obtained by successive approximation technique. In this paper the focus will be on all-around efficient circuit for enhancing resolution of 8-bit Flash ADC. It is shown that by adopting this configuration, we can obtain 12-bit digital data just using 256 comparators. Therefore this technique is best suitable when high speed combined with high resolution is required. An experimental prototype of proposed 12-bit ADC was implemented using Philips P89V51RD2BN Microcontroller. Use of Microcontroller has greatly reduced the hardware requirement and cost. An ADC result of 12-bit prototype is presented. The results show that the ADC exhibits a maximum DNL of 0.52LSB and a maximum INL of 0.55LSB.
Effect of bit wear on hammer drill handle vibration and productivity.
Antonucci, Andrea; Barr, Alan; Martin, Bernard; Rempel, David
2017-08-01
The use of large electric hammer drills exposes construction workers to high levels of hand vibration that may lead to hand-arm vibration syndrome and other musculoskeletal disorders. The aim of this laboratory study was to investigate the effect of bit wear on drill handle vibration and drilling productivity (e.g., drilling time per hole). A laboratory test bench system was used with an 8.3 kg electric hammer drill and 1.9 cm concrete bit (a typical drill and bit used in commercial construction). The system automatically advanced the active drill into aged concrete block under feed force control to a depth of 7.6 cm while handle vibration was measured according to ISO standards (ISO 5349 and 28927). Bits were worn to 4 levels by consecutive hole drilling to 4 cumulative drilling depths: 0, 1,900, 5,700, and 7,600 cm. Z-axis handle vibration increased significantly (pvibration did not increase further with bits worn more than 1900 cm of cumulative drilling depth. Neither x- nor y-axis handle vibration was effected by bit wear. The time to drill a hole increased by 58% for the bit with 5,700 cm of cumulative drilling depth compared to a new bit. Bit wear led to a small but significant increase in both ISO weighted and unweighted z-axis handle vibration. Perhaps more important, bit wear had a large effect on productivity. The effect on productivity will influence a worker's allowable daily drilling time if exposure to drill handle vibration is near the ACGIH Threshold Limit Value. ([1]) Construction contractors should implement a bit replacement program based on these findings.
The anoikis effector Bit1 displays tumor suppressive function in lung cancer cells.
Directory of Open Access Journals (Sweden)
Xin Yao
Full Text Available The mitochondrial Bit1 (Bcl-2 inhibitor of transcription 1 protein is a part of an apoptotic pathway that is uniquely regulated by integrin-mediated attachment. As an anoikis effector, Bit1 is released into the cytoplasm following loss of cell attachment and induces a caspase-independent form of apoptosis. Considering that anoikis resistance is a critical determinant of transformation, we hypothesized that cancer cells may circumvent the Bit1 apoptotic pathway to attain anchorage-independence and tumorigenic potential. Here, we provide the first evidence of the tumor suppressive effect of Bit1 through a mechanism involving anoikis induction in human lung adenocarcinoma derived A549 cells. Restitution of Bit1 in anoikis resistant A549 cells is sufficient to induce detachment induced-apoptosis despite defect in caspase activation and impairs their anchorage-independent growth. Conversely, stable downregulation of Bit1 in these cells significantly enhances their anoikis resistance and anchorage-independent growth. The Bit1 knockdown cells exhibit significantly enhanced tumorigenecity in vivo. It has been previously shown that the nuclear TLE1 corepressor is a putative oncogene in lung cancer, and we show here that TLE1 blocks Bit1 mediated anoikis in part by sequestering the pro-apoptotic partner of Bit1, the Amino-terminal Enhancer of Split (AES protein, in the nucleus. Taken together, these findings suggest a tumor suppressive role of the caspase-independent anoikis effector Bit1 in lung cancer. Consistent with its role as a tumor suppressor, we have found that Bit1 is downregulated in human non-small cell lung cancer (NSCLC tissues.
The anoikis effector Bit1 displays tumor suppressive function in lung cancer cells.
Yao, Xin; Jennings, Scott; Ireland, Shubha Kale; Pham, Tri; Temple, Brandi; Davis, Mya; Chen, Renwei; Davenport, Ian; Biliran, Hector
2014-01-01
The mitochondrial Bit1 (Bcl-2 inhibitor of transcription 1) protein is a part of an apoptotic pathway that is uniquely regulated by integrin-mediated attachment. As an anoikis effector, Bit1 is released into the cytoplasm following loss of cell attachment and induces a caspase-independent form of apoptosis. Considering that anoikis resistance is a critical determinant of transformation, we hypothesized that cancer cells may circumvent the Bit1 apoptotic pathway to attain anchorage-independence and tumorigenic potential. Here, we provide the first evidence of the tumor suppressive effect of Bit1 through a mechanism involving anoikis induction in human lung adenocarcinoma derived A549 cells. Restitution of Bit1 in anoikis resistant A549 cells is sufficient to induce detachment induced-apoptosis despite defect in caspase activation and impairs their anchorage-independent growth. Conversely, stable downregulation of Bit1 in these cells significantly enhances their anoikis resistance and anchorage-independent growth. The Bit1 knockdown cells exhibit significantly enhanced tumorigenecity in vivo. It has been previously shown that the nuclear TLE1 corepressor is a putative oncogene in lung cancer, and we show here that TLE1 blocks Bit1 mediated anoikis in part by sequestering the pro-apoptotic partner of Bit1, the Amino-terminal Enhancer of Split (AES) protein, in the nucleus. Taken together, these findings suggest a tumor suppressive role of the caspase-independent anoikis effector Bit1 in lung cancer. Consistent with its role as a tumor suppressor, we have found that Bit1 is downregulated in human non-small cell lung cancer (NSCLC) tissues.
Circulation-preserving plane flows of incompressible viscous fluids
Yin, W.-L.
1983-06-01
The present investigation is concerned with a systematic use of the method of complex variables in a study of (generally unsteady) plane solutions of the Navier-Stokes equation. Circulation-preserving flows are considered in the investigation. However, the employed method can also be applied to more general cases. A circulation-preserving plane solution of the Navier-Stokes equation possesses a biharmonic stream function. The stream function may, therefore, be expressed in terms of two complex analytic functions, taking into account Goursat's representation. Attention is given to differential equations in the complex form, the case of steady vorticity, the case of unsteady vorticity with a spatially constant vorticity gradient, solutions with logarithmic vorticity fields, and a proof of completeness.
Energy Technology Data Exchange (ETDEWEB)
Abe, M.; Niitsuma, H. (Tohoku Univ., Sendai (Japan). Faculty of Engineering); Sugimori, S. (Tohoku Univ., Sendai (Japan). Grauduate School); Nakajima, T. (NKK Corp., Tokyo (Japan))
1991-09-20
The accuracy of the bit location in the excavation of pilot holes with horizontal drilling technique must be kept less than several tens of centimeters. Such an accuracy is hard to be achieved by the existing controlling technology. The depth of the bit tip can be measured comparatively accurately using a clinometer and the like. The azimuth meter, gyroscope, underground radar, locator, etc. are used for the detection of azimuth of the bit, but every one of them has its own problem. Therefore, new measuring methods to be used in combination with the conventional methods are required which can cover up the shortcomings of the conventional methods. Acoustic emission (AE) technique is employed for the detection of the bit location, and the accompanying problems as well as detecting performance are investigated. It is used for the measurement in the drilling test performed at the reclaimed land on the premises of Keihin ironworks of NKK Corp. In connection with the detection of the bit location in horizontal pilot drilling, a study is made on the zone detection technique for AE signals generated by the bit when striking ground and those generated during drilling. 7 refs., 17 figs., 1 tab.
The INTEGRAL Galactic Plane Scanning
Fiocchi, Mariateresa
2013-01-01
After the first nine years of INTEGRAL operational life, the discovery of new sources and source types, a large fraction of which are highly transient or highly absorbed, is certainly one of the most compelling results and legacies of INTEGRAL. Frequent monitoring of the Galactic Plane in AO8 and AO9 campaigns allowed us to detect transient sources, both known and new, confirming that the gamma-ray sky is dominated by the extreme variability of different classes of objects. Regular scans of the Galactic Plane by INTEGRAL provide the most sensitive hard X-ray wide survey to date of our Galaxy, with flux limits of the order of 0.3 mCrab for an exposure time of ~2Ms. Many transient sources have been detected on a wide range of time scales (~hours to months) and identified by triggered followup observations, mainly by Swift/XRT and optical/infrared telescopes. These discoveries are very important to characterize the X-ray binary population in our Galaxy, that is necessary input for evolution studies. The transien...
The HAWC Galactic Plane Survey
Hui, Michelle
2016-03-01
The High Altitude Water Cherenkov (HAWC) Observatory is an all-sky surveying instrument that covers 2/3 of the sky in 24 hours. It is designed with an emphasis on continuous sky coverage for transient events, and on the measurement of extended and large-scale structures. The array is located in Sierra Negra, Mexico at an elevation of 4,100 m and was inaugurated in March 2015. The HAWC array consists of 300 water Cherenkov detectors and is sensitive to extensive air showers triggered by cosmic rays and gamma rays from 100 GeV to >100 TeV. Thanks to its modular design, data taking began in Summer 2013 with 1/3 of the array. Analysis of the first year of data with the partial array shows detections that are coincident with known TeV supernova remnants and pulsar wind nebulae along the Galactic plane. Spectral and morphological analyses are ongoing to study the particle population and acceleration mechanism of these objects. With a growing data set taken with the completed array, source searches are underway for both point-like and extended emission along the Galactic plane, which contain many objects such as pulsar wind nebulae, young star clusters, and binaries.
Lines, Circles, Planes and Spheres
Purdy, George B
2009-01-01
Let $S$ be a set of $n$ points in $\\mathbb{R}^3$, no three collinear and not all coplanar. If at most $n-k$ are coplanar and $n$ is sufficiently large, the total number of planes determined is at least $1 + k \\binom{n-k}{2}-\\binom{k}{2}(\\frac{n-k}{2})$. For similar conditions and sufficiently large $n$, (inspired by the work of P. D. T. A. Elliott in \\cite{Ell67}) we also show that the number of spheres determined by $n$ points is at least $1+\\binom{n-1}{3}-t_3^{orchard}(n-1)$, and this bound is best possible under its hypothesis. (By $t_3^{orchard}(n)$, we are denoting the maximum number of three-point lines attainable by a configuration of $n$ points, no four collinear, in the plane, i.e., the classic Orchard Problem.) New lower bounds are also given for both lines and circles.
Singularities from colliding plane gravitational waves
Tipler, Frank J.
1980-12-01
A simple geometrical argument is given which shows that a collision between two plane gravitational waves must result in singularities. The argument suggests that these singularities are a peculiar feature of plane waves, because singularities are also a consequence of a collision between self-gravitating plane waves of other fields with arbitrarily small energy density.
Singularities from colliding plane gravitational waves
Energy Technology Data Exchange (ETDEWEB)
Tipler, F.J.
1980-12-15
A simple geometrical argument is given which shows that a collision between two plane gravitational waves must result in singularities. The argument suggests that these singularities are a peculiar feature of plane waves, because singularities are also a consequence of a collision between self-gravitating plane waves of other fields with arbitrarily small energy density.
Evolved stars in galactic plane surveys
Verbeek, K.
2013-01-01
For the first time in history the entire Galactic Plane is digitally mapped from La Palma and Chile by the European Galactic Plane surveys EGAPS (UVEX, IPHAS and VPHAS+, see http://www.uvexsurvey.org http://www.iphas.org and http://www.vphasplus.org). The complete Galactic plane (3600 square degrees
Homogeneity and plane-wave limits
Figueroa-O'Farrill, J M; Philip, S; Farrill, Jos\\'e Figueroa-O'; Meessen, Patrick; Philip, Simon
2005-01-01
We explore the plane-wave limit of homogeneous spacetimes. For plane-wave limits along homogeneous geodesics the limit is known to be homogeneous and we exhibit the limiting metric in terms of Lie algebraic data. This simplifies many calculations and we illustrate this with several examples. We also investigate the behaviour of (reductive) homogeneous structures under the plane-wave limit.
A 16-bit Coherent Ising Machine for One-Dimensional Ring and Cubic Graph Problems
Takata, Kenta; Marandi, Alireza; Hamerly, Ryan; Haribara, Yoshitaka; Maruo, Daiki; Tamate, Shuhei; Sakaguchi, Hiromasa; Utsunomiya, Shoko; Yamamoto, Yoshihisa
2016-09-01
Many tasks in our modern life, such as planning an efficient travel, image processing and optimizing integrated circuit design, are modeled as complex combinatorial optimization problems with binary variables. Such problems can be mapped to finding a ground state of the Ising Hamiltonian, thus various physical systems have been studied to emulate and solve this Ising problem. Recently, networks of mutually injected optical oscillators, called coherent Ising machines, have been developed as promising solvers for the problem, benefiting from programmability, scalability and room temperature operation. Here, we report a 16-bit coherent Ising machine based on a network of time-division-multiplexed femtosecond degenerate optical parametric oscillators. The system experimentally gives more than 99.6% of success rates for one-dimensional Ising ring and nondeterministic polynomial-time (NP) hard instances. The experimental and numerical results indicate that gradual pumping of the network combined with multiple spectral and temporal modes of the femtosecond pulses can improve the computational performance of the Ising machine, offering a new path for tackling larger and more complex instances.
Communication complexity and information complexity
Pankratov, Denis
Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information
Single-plane multiple speckle pattern phase retrieval using a deformable mirror
DEFF Research Database (Denmark)
Almoro, Percival F.; Glückstad, Jesper; Hanson, Steen Grüner
2010-01-01
A design for a single-plane multiple speckle pattern phase retrieval technique using a deformable mirror (DM) is analyzed within the formalism of complex ABCD-matrices, facilitating its use in conjunction with dynamic wavefronts. The variable focal length DM positioned at a Fourier plane of a lens...
Technique for evaluating antiwear properties of lubricant grease for GN and GNU drill bits
Energy Technology Data Exchange (ETDEWEB)
Gubarev, A.S.; Butovets, V.V.; Dyachenko, Yu.P.; Krasnokutskaya, M.Ye.; Nedbaylyuk, P.Ye.; Oparin, V.A.; Yeremenko, V.F.
1982-01-01
A technique has been developed for determining under laboratory conditions the antiwear characteristics for lubricant grease used for drill bit supports models GN and GNU. A satisfactory coincidence of test results of lubricants USsA and Uniol-1 has been derived using the given technique, as well as satisfactory results for the drill bits operating in industrial conditions.
Dispersion Tolerance of 40 Gbaud Multilevel Modulation Formats with up to 3 bits per Symbol
DEFF Research Database (Denmark)
Jensen, Jesper Bevensee; Tokle, Torger; Geng, Yan
2006-01-01
We present numerical and experimental investigations of dispersion tolerance for multilevel phase- and amplitude modulation with up to 3 bits per symbol at a symbol rate of 40 Gbaud......We present numerical and experimental investigations of dispersion tolerance for multilevel phase- and amplitude modulation with up to 3 bits per symbol at a symbol rate of 40 Gbaud...
Up to 20 Gbit/s bit-rate transparent integrated interferometric wavelength converter
DEFF Research Database (Denmark)
Jørgensen, Carsten; Danielsen, Søren Lykke; Hansen, Peter Bukhave;
1996-01-01
We present a compact and optimised multiquantum-well based, integrated all-active Michelson interferometer for 26 Gbit/s optical wavelength conversion. Bit-rate transparent operation is demonstrated with a conversion penalty well below 0.5 dB at bit-rates ranging from 622 Mbit/s to 20 Gbit/s....
Mutual information, bit error rate and security in W\\'{o}jcik's scheme
Zhang, Z
2004-01-01
In this paper the correct calculations of the mutual information of the whole transmission, the quantum bit error rate (QBER) are presented. Mistakes of the general conclusions relative to the mutual information, the quantum bit error rate (QBER) and the security in W\\'{o}jcik's paper [Phys. Rev. Lett. {\\bf 90}, 157901(2003)] have been pointed out and corrected.
Enhanced bit rate-distance product impulse radio ultra-wideband over fiber link
DEFF Research Database (Denmark)
Rodes Lopez, Roberto; Jensen, Jesper Bevensee; Caballero Jambrina, Antonio
2010-01-01
We report on a record distance and bit rate-wireless impulse radio (IR) ultra-wideband (UWB) link with combined transmission over a 20 km long fiber link. We are able to improve the compliance with the regulated frequency emission mask and achieve bit rate-distance products as high as 16 Gbit/s·m....
Purpose-built PDC bit successfully drills 7-in liner equipment and formation: An integrated solution
Energy Technology Data Exchange (ETDEWEB)
Puennel, J.G.A.; Huppertz, A.; Huizing, J. [and others
1996-12-31
Historically, drilling out the 7-in, liner equipment has been a time consuming operation with a limited success ratio. The success of the operation is highly dependent on the type of drill bit employed. Tungsten carbide mills and mill tooth rock bits required from 7.5 to 11.5 hours respectively to drill the pack-off bushings, landing collar, shoe track and shoe. Rates of penetration dropped dramatically when drilling the float equipment. While conventional PDC bits have drilled the liner equipment successfully (averaging 9.7 hours), severe bit damage invariably prevented them from continuing to drill the formation at cost-effective penetration rates. This paper describes the integrated development and application of an IADC M433 Class PDC bit, which was designed specifically to drill out the 7-in. liner equipment and continue drilling the formation at satisfactory penetration rates. The development was the result of a joint investigation There the operator and bit/liner manufacturers shared their expertise in solving a drilling problem, The heavy-set bit was developed following drill-off tests conducted to investigate the drillability of the 7-in. liner equipment. Key features of the new bit and its application onshore The Netherlands will be presented and analyzed.
On swarm-level resource allocation in BitTorrent communities
Vinko, T.; Santos, F.; Andrade, N.; Capota, M.
2012-01-01
BitTorrent is a peer-to-peer computer network protocol for sharing content in an efficient and scalable way. Modeling and analysis of the popular private BitTorrent communities has become an active area of research. In these communities users are strongly incentivized to contribute their resources,
Application of time-hopping UWB range-bit rate performance in the UWB sensor networks
Nascimento, J.R.V. do; Nikookar, H.
2008-01-01
In this paper, the achievable range-bit rate performance is evaluated for Time-Hopping (TH) UWB networks complying with the FCC outdoor emission limits in the presence of Multiple Access Interference (MAI). Application of TH-UWB range-bit rate performance is presented for UWB sensor networks. Result
An Auction-Bidding Protocol for Distributed Bit Allocation in RSSI-based Localization Networks
Directory of Open Access Journals (Sweden)
Ahmad A. Ababneh
2016-06-01
Full Text Available Several factors (e.g., target energy, sensor density affect estimation error at a point of interest in sensor networks. One of these factors is the number of allocated bits to sensors that cover the point of interest when quantization is employed. In this paper, we investigate bit allocation in such networks such that estimation error requirements at multiple points of interest are satisfied as best as possible. To solve this nonlinear integer programming problem, we propose an iterative distributed auctionbidding protocol. Starting with some initial bit distribution, a network is divided into a a number of clusters each with its own auction. Each cluster head (CH acts as an auctioneer and divides sensors into buyers or sellers of bits (i.e., commodity. With limited messaging, CHs redistribute bits among sensors, each bit at a time such that the difference between achieved and required estimation errors within each cluster is reduced in each round. We propose two bit-pricing schemes used by sensors to decide on exchanging bits. Finally, simulation results show that our proposed ‘distributed’ protocol’s error performance can be within 5%-10% of that of a ‘centralized’ genetic algorithm (GA solution.
Least Reliable Bits Coding (LRBC) for high data rate satellite communications
Vanderaar, Mark; Wagner, Paul; Budinger, James
1992-02-01
An analysis and discussion of a bandwidth efficient multi-level/multi-stage block coded modulation technique called Least Reliable Bits Coding (LRBC) is presented. LRBC uses simple multi-level component codes that provide increased error protection on increasingly unreliable modulated bits in order to maintain an overall high code rate that increases spectral efficiency. Further, soft-decision multi-stage decoding is used to make decisions on unprotected bits through corrections made on more protected bits. Using analytical expressions and tight performance bounds it is shown that LRBC can achieve increased spectral efficiency and maintain equivalent or better power efficiency compared to that of Binary Phase Shift Keying (BPSK). Bit error rates (BER) vs. channel bit energy with Additive White Gaussian Noise (AWGN) are given for a set of LRB Reed-Solomon (RS) encoded 8PSK modulation formats with an ensemble rate of 8/9. All formats exhibit a spectral efficiency of 2.67 = (log2(8))(8/9) information bps/Hz. Bit by bit coded and uncoded error probabilities with soft-decision information are determined. These are traded with with code rate to determine parameters that achieve good performance. The relative simplicity of Galois field algebra vs. the Viterbi algorithm and the availability of high speed commercial Very Large Scale Integration (VLSI) for block codes indicates that LRBC using block codes is a desirable method for high data rate implementations.
Towards the generation of random bits at terahertz rates based on a chaotic semiconductor laser
Kanter, Ido; Aviad, Yaara; Reidler, Igor; Cohen, Elad; Rosenbluh, Michael
2010-06-01
Random bit generators (RBGs) are important in many aspects of statistical physics and crucial in Monte-Carlo simulations, stochastic modeling and quantum cryptography. The quality of a RBG is measured by the unpredictability of the bit string it produces and the speed at which the truly random bits can be generated. Deterministic algorithms generate pseudo-random numbers at high data rates as they are only limited by electronic hardware speed, but their unpredictability is limited by the very nature of their deterministic origin. It is widely accepted that the core of any true RBG must be an intrinsically non-deterministic physical process, e.g. measuring thermal noise from a resistor. Owing to low signal levels, such systems are highly susceptible to bias, introduced by amplification, and to small nonrandom external perturbations resulting in a limited generation rate, typically less than 100M bit/s. We present a physical random bit generator, based on a chaotic semiconductor laser, having delayed optical feedback, which operates reliably at rates up to 300Gbit/s. The method uses a high derivative of the digitized chaotic laser intensity and generates the random sequence by retaining a number of the least significant bits of the high derivative value. The method is insensitive to laser operational parameters and eliminates the necessity for all external constraints such as incommensurate sampling rates and laser external cavity round trip time. The randomness of long bit strings is verified by standard statistical tests.
Bit and Power Loading Approach for Broadband Multi-Antenna OFDM System
DEFF Research Database (Denmark)
Rahman, Muhammad Imadur; Das, Suvra S.; Wang, Yuanye
2007-01-01
In this work, we have studied bit and power allocation strategies for multi-antenna assisted Orthogonal Frequency Division Multiplexing (OFDM) systems and investigated the impact of different rates of bit and power allocations on various multi-antenna diversity schemes. It is observed that, if we...... allocations across OFDM sub-channels are required together for efficient exploitation of wireless channel....
High power laser-mechanical drilling bit and methods of use
Energy Technology Data Exchange (ETDEWEB)
Grubb, Daryl L.; Kolachalam, Sharath K.; Faircloth, Brian O.; Rinzler, Charles C.; Allen, Erik C.; Underwood, Lance D.; Zediker, Mark S.
2017-02-07
An apparatus with a high power laser-mechanical bit for use with a laser drilling system and a method for advancing a borehole. The laser-mechanical bit has a beam path and mechanical removal devices that provide for the removal of laser-affected rock to advance a borehole.
Focal-plane CMOS wavelet feature extraction for real-time pattern recognition
Olyaei, Ashkan; Genov, Roman
2005-09-01
Kernel-based pattern recognition paradigms such as support vector machines (SVM) require computationally intensive feature extraction methods for high-performance real-time object detection in video. The CMOS sensory parallel processor architecture presented here computes delta-sigma (ΔΣ)-modulated Haar wavelet transform on the focal plane in real time. The active pixel array is integrated with a bank of column-parallel first-order incremental oversampling analog-to-digital converters (ADCs). Each ADC performs distributed spatial focal-plane sampling and concurrent weighted average quantization. The architecture is benchmarked in SVM face detection on the MIT CBCL data set. At 90% detection rate, first-level Haar wavelet feature extraction yields a 7.9% reduction in the number of false positives when compared to classification with no feature extraction. The architecture yields 1.4 GMACS simulated computational throughput at SVGA imager resolution at 8-bit output depth.
An introduction to finite projective planes
Albert, Abraham Adrian
2015-01-01
Geared toward both beginning and advanced undergraduate and graduate students, this self-contained treatment offers an elementary approach to finite projective planes. Following a review of the basics of projective geometry, the text examines finite planes, field planes, and coordinates in an arbitrary plane. Additional topics include central collineations and the little Desargues' property, the fundamental theorem, and examples of finite non-Desarguesian planes.Virtually no knowledge or sophistication on the part of the student is assumed, and every algebraic system that arises is defined and
An 18-bit high performance audio {sigma}-{Delta} D/A converter
Energy Technology Data Exchange (ETDEWEB)
Zhang Hao; Han Yan; Han Xiaoxia; Wang Hao; Liang Guo [Institute of Microelectronics and Photoelectronics, Zhejiang University, Hangzhou 310027 (China); Huang Xiaowei [CISD, Institute of Microelectronic CAD, Hangzhou 310018 (China); Cheung, Ray C., E-mail: huangxw@hdu.edu.c [Department of Electronic Engineering, City University of Hong Kong (Hong Kong)
2010-07-15
A multi-bit quantized high performance sigma-delta ({sigma}-{Delta}) audio DAC is presented. Compared to its single-bit counterpart, the multi-bit quantization offers many advantages, such as simpler {sigma}-{Delta} modulator circuit, lower clock frequency and smaller spurious tones. With the data weighted average (DWA) mismatch shaping algorithm, element mismatch errors induced by multi-bit quantization can be pushed out of the signal band, hence the noise floor inside the signal band is greatly lowered. To cope with the crosstalk between digital and analog circuits, every analog component is surrounded by a guard ring, which is an innovative attempt. The 18-bit DAC with the above techniques, which is implemented in a 0.18 {mu}m mixed-signal CMOS process, occupies a core area of 1.86 mm{sup 2}. The measured dynamic range (DR) and peak SNDR are 96 dB and 88 dB, respectively.
Tree structure-based bit-to-symbol mapping for multidimensional modulation format
Zhaoxi, Li; Yujuan, Si; Guijun, Hu
2017-06-01
Bit-to-symbol mapping is one of the key issues in multidimensional modulation. In an effort to resolve this issue, a tree structure based bit-to-symbol mapping scheme is proposed. By constructing a tree structure of constellation points, any neighboring constellation points become nearest-neighbor constellation points with minimum Euclidean distance, which in turn, changes the bit-to-symbol mapping problem in multidimensional signal modulation from random to orderly. Then, through the orderly distribution of labels, the minimum Hamming distance between the nearest neighboring constellation points is ensured, eventually achieving bit-to-symbol mapping optimization for multidimensional signals. Simulation analysis indicates that, compared with random search mapping, tree mapping can effectively improve the bit error rate performance of multidimensional signal modulation without multiple searching, reducing the computational cost.