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Sample records for bit floating point

  1. Quantifying the Impact of Single Bit Flips on Floating Point Arithmetic

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, James J [ORNL; Mueller, Frank [North Carolina State University; Stoyanov, Miroslav K [ORNL; Webster, Clayton G [ORNL

    2013-08-01

    In high-end computing, the collective surface area, smaller fabrication sizes, and increasing density of components have led to an increase in the number of observed bit flips. If mechanisms are not in place to detect them, such flips produce silent errors, i.e. the code returns a result that deviates from the desired solution by more than the allowed tolerance and the discrepancy cannot be distinguished from the standard numerical error associated with the algorithm. These phenomena are believed to occur more frequently in DRAM, but logic gates, arithmetic units, and other circuits are also susceptible to bit flips. Previous work has focused on algorithmic techniques for detecting and correcting bit flips in specific data structures, however, they suffer from lack of generality and often times cannot be implemented in heterogeneous computing environment. Our work takes a novel approach to this problem. We focus on quantifying the impact of a single bit flip on specific floating-point operations. We analyze the error induced by flipping specific bits in the most widely used IEEE floating-point representation in an architecture-agnostic manner, i.e., without requiring proprietary information such as bit flip rates and the vendor-specific circuit designs. We initially study dot products of vectors and demonstrate that not all bit flips create a large error and, more importantly, expected value of the relative magnitude of the error is very sensitive on the bit pattern of the binary representation of the exponent, which strongly depends on scaling. Our results are derived analytically and then verified experimentally with Monte Carlo sampling of random vectors. Furthermore, we consider the natural resilience properties of solvers based on the fixed point iteration and we demonstrate how the resilience of the Jacobi method for linear equations can be significantly improved by rescaling the associated matrix.

  2. Hardware description ADSP-21020 40-bit floating point DSP as designed in a remotely controlled digital CW Doppler radar

    Science.gov (United States)

    Morrison, R. E.; Robinson, S. H.

    A continuous wave Doppler radar system has been designed which is portable, easily deployed, and remotely controlled. The heart of this system is a DSP/control board using Analog Devices ADSP-21020 40-bit floating point digital signal processor (DSP) microprocessor. Two 18-bit audio A/D converters provide digital input to the DSP/controller board for near real time target detection. Program memory for the DSP is dual ported with an Intel 87C51 microcontroller allowing DSP code to be up-loaded or down-loaded from a central controlling computer. The 87C51 provides overall system control for the remote radar and includes a time-of-day/day-of-year real time clock, system identification (ID) switches, and input/output (I/O) expansion by an Intel 82C55 I/O expander.

  3. IEEE Standard for Floating Point Numbers

    Indian Academy of Sciences (India)

    IAS Admin

    Floating point numbers are an important data type in compu- tation which is used ... quite large! Integers are ... exp, the value of the exponent will be taken as (exp –127). The ..... bit which is truncated is 1, add 1 to the least significant bit, else.

  4. Implementing floating-point DSP

    Czech Academy of Sciences Publication Activity Database

    Kadlec, Jiří; Chappel, S.

    2006-01-01

    Roč. 2, č. 3 (2006), s. 12-14 R&D Projects: GA AV ČR 1ET400750406; GA MŠk 1M0567 EU Projects: European Commission(XE) 027611 - AETHER Program:FP6 Institutional research plan: CEZ:AV0Z10750506 Keywords : PicoBlaze * floating point * FPGA Subject RIV: JC - Computer Hardware ; Software http://www.xilinx.com/publications/ magazines /emb_03/xc_pdf/p12-14_3emb-point.pdf

  5. A custom floating point format ADC for LHC calorimetry

    International Nuclear Information System (INIS)

    Hermel, V.; Lecoq, J.; Bohner, G.

    1996-01-01

    Due to their large dynamic range (in excess of 16 bits) signals from LHC calorimetry poses severe problems to the shaping and digitizing circuits. We are investigating a solution for an ADC based on a custom floating point format. Since the calorimeter precision is limited, the full dynamic range can be split into 8 positive sub-ranges and 5 negative ones, each with an 8 bits dynamic. The reduced number of bits (8 for the mantissa, 4 for the exponent and 1 for the sign) translates itself into a reduction of the power consumption both of the ADC and of the following digital filtering stages. (authors)

  6. Handbook of floating-point arithmetic

    CERN Document Server

    Muller, Jean-Michel; de Dinechin, Florent; Jeannerod, Claude-Pierre; Joldes, Mioara; Lefèvre, Vincent; Melquiond, Guillaume; Revol, Nathalie; Torres, Serge

    2018-01-01

    This handbook is a definitive guide to the effective use of modern floating-point arithmetic, which has considerably evolved, from the frequently inconsistent floating-point number systems of early computing to the recent IEEE 754-2008 standard. Most of computational mathematics depends on floating-point numbers, and understanding their various implementations will allow readers to develop programs specifically tailored for the standard’s technical features. Algorithms for floating-point arithmetic are presented throughout the book and illustrated where possible by example programs which show how these techniques appear in actual coding and design. The volume itself breaks its core topic into four parts: the basic concepts and history of floating-point arithmetic; methods of analyzing floating-point algorithms and optimizing them; implementations of IEEE 754-2008 in hardware and software; and useful extensions to the standard floating-point system, such as interval arithmetic, double- and triple-word arithm...

  7. Fixed-Rate Compressed Floating-Point Arrays.

    Science.gov (United States)

    Lindstrom, Peter

    2014-12-01

    Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation.

  8. An Asynchronous IEEE Floating-Point Arithmetic Unit

    Directory of Open Access Journals (Sweden)

    Joel R. Noche

    2007-12-01

    Full Text Available An asynchronous floating-point arithmetic unit is designed and tested at the transistor level usingCadence software. It uses CMOS (complementary metal oxide semiconductor and DCVS (differentialcascode voltage switch logic in a 0.35 µm process using a 3.3 V supply voltage, with dual-rail data andsingle-rail control signals using four-phase handshaking.Using 17,085 transistors, the unit handles single-precision (32-bit addition/subtraction, multiplication,division, and remainder using the IEEE 754-1985 Standard for Binary Floating-Point Arithmetic, withrounding and other operations to be handled by separate hardware or software. Division and remainderare done using a restoring subtractive algorithm; multiplication uses an additive algorithm. Exceptionsare noted by flags (and not trap handlers and the output is in single-precision.Previous work on asynchronous floating-point arithmetic units have mostly focused on single operationssuch as division. This is the first work to the authors' knowledge that can perform floating-point addition,multiplication, division, and remainder using a common datapath.

  9. 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf | 01 ...

    Indian Academy of Sciences (India)

    Home; public; Volumes; reso; 021; 01; 0011-0030.IEEE 754: 64 Bit Double Precision FloatsThis.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. 29th Mid-year meeting. Posted on 19 ...

  10. Apparatus and method for implementing power saving techniques when processing floating point values

    Science.gov (United States)

    Kim, Young Moon; Park, Sang Phill

    2017-10-03

    An apparatus and method are described for reducing power when reading and writing graphics data. For example, one embodiment of an apparatus comprises: a graphics processor unit (GPU) to process graphics data including floating point data; a set of registers, at least one of the registers of the set partitioned to store the floating point data; and encode/decode logic to reduce a number of binary 1 values being read from the at least one register by causing a specified set of bit positions within the floating point data to be read out as 0s rather than 1s.

  11. Pc-Based Floating Point Imaging Workstation

    Science.gov (United States)

    Guzak, Chris J.; Pier, Richard M.; Chinn, Patty; Kim, Yongmin

    1989-07-01

    The medical, military, scientific and industrial communities have come to rely on imaging and computer graphics for solutions to many types of problems. Systems based on imaging technology are used to acquire and process images, and analyze and extract data from images that would otherwise be of little use. Images can be transformed and enhanced to reveal detail and meaning that would go undetected without imaging techniques. The success of imaging has increased the demand for faster and less expensive imaging systems and as these systems become available, more and more applications are discovered and more demands are made. From the designer's perspective the challenge to meet these demands forces him to attack the problem of imaging from a different perspective. The computing demands of imaging algorithms must be balanced against the desire for affordability and flexibility. Systems must be flexible and easy to use, ready for current applications but at the same time anticipating new, unthought of uses. Here at the University of Washington Image Processing Systems Lab (IPSL) we are focusing our attention on imaging and graphics systems that implement imaging algorithms for use in an interactive environment. We have developed a PC-based imaging workstation with the goal to provide powerful and flexible, floating point processing capabilities, along with graphics functions in an affordable package suitable for diverse environments and many applications.

  12. Floating-to-Fixed-Point Conversion for Digital Signal Processors

    Directory of Open Access Journals (Sweden)

    Menard Daniel

    2006-01-01

    Full Text Available Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

  13. Floating-to-Fixed-Point Conversion for Digital Signal Processors

    Science.gov (United States)

    Menard, Daniel; Chillet, Daniel; Sentieys, Olivier

    2006-12-01

    Digital signal processing applications are specified with floating-point data types but they are usually implemented in embedded systems with fixed-point arithmetic to minimise cost and power consumption. Thus, methodologies which establish automatically the fixed-point specification are required to reduce the application time-to-market. In this paper, a new methodology for the floating-to-fixed point conversion is proposed for software implementations. The aim of our approach is to determine the fixed-point specification which minimises the code execution time for a given accuracy constraint. Compared to previous methodologies, our approach takes into account the DSP architecture to optimise the fixed-point formats and the floating-to-fixed-point conversion process is coupled with the code generation process. The fixed-point data types and the position of the scaling operations are optimised to reduce the code execution time. To evaluate the fixed-point computation accuracy, an analytical approach is used to reduce the optimisation time compared to the existing methods based on simulation. The methodology stages are described and several experiment results are presented to underline the efficiency of this approach.

  14. Power Dissipation Challenges in Multicore Floating-Point Units

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2010-01-01

    , we analyze the impact of power dissipation in floating-point (FP) units and we consider different alternatives in the implementation of FP-division that lead to substantial energy savings. We compare the implementation of division in a Fused Multiply-Add (FMA) unit based on the Newton-Raphson...

  15. Sabrewing: A lightweight architecture for combined floating-point and integer arithmetic

    NARCIS (Netherlands)

    Bruintjes, Tom; Walters, K.H.G.; Gerez, Sabih H.; Molenkamp, Egbert; Smit, Gerardus Johannes Maria

    In spite of the fact that floating-point arithmetic is costly in terms of silicon area, the joint design of hardware for floating-point and integer arithmetic is seldom considered. While components like multipliers and adders can potentially be shared, floating-point and integer units in

  16. A vertically integrated dynamic RAM-cell: Buried bit line memory cell with floating transfer layer

    NARCIS (Netherlands)

    Mouthaan, A.J.; Vertregt, Maarten

    1986-01-01

    A charge injection device has been realized in which charge can be injected on to an MOS-capacitor from a buried layer via an isolated transfer layer. The cell is positioned vertically between word and bit line. LOCOS (local oxidation) is used to isolate the cells and (deep) ion implantation to

  17. High-performance floating-point image computing workstation for medical applications

    Science.gov (United States)

    Mills, Karl S.; Wong, Gilman K.; Kim, Yongmin

    1990-07-01

    The medical imaging field relies increasingly on imaging and graphics techniques in diverse applications with needs similar to (or more stringent than) those of the military, industrial and scientific communities. However, most image processing and graphics systems available for use in medical imaging today are either expensive, specialized, or in most cases both. High performance imaging and graphics workstations which can provide real-time results for a number of applications, while maintaining affordability and flexibility, can facilitate the application of digital image computing techniques in many different areas. This paper describes the hardware and software architecture of a medium-cost floating-point image processing and display subsystem for the NeXT computer, and its applications as a medical imaging workstation. Medical imaging applications of the workstation include use in a Picture Archiving and Communications System (PACS), in multimodal image processing and 3-D graphics workstation for a broad range of imaging modalities, and as an electronic alternator utilizing its multiple monitor display capability and large and fast frame buffer. The subsystem provides a 2048 x 2048 x 32-bit frame buffer (16 Mbytes of image storage) and supports both 8-bit gray scale and 32-bit true color images. When used to display 8-bit gray scale images, up to four different 256-color palettes may be used for each of four 2K x 2K x 8-bit image frames. Three of these image frames can be used simultaneously to provide pixel selectable region of interest display. A 1280 x 1024 pixel screen with 1: 1 aspect ratio can be windowed into the frame buffer for display of any portion of the processed image or images. In addition, the system provides hardware support for integer zoom and an 82-color cursor. This subsystem is implemented on an add-in board occupying a single slot in the NeXT computer. Up to three boards may be added to the NeXT for multiple display capability (e

  18. Optimized Latching Control of Floating Point Absorber Wave Energy Converter

    Science.gov (United States)

    Gadodia, Chaitanya; Shandilya, Shubham; Bansal, Hari Om

    2018-03-01

    There is an increasing demand for energy in today’s world. Currently main energy resources are fossil fuels, which will eventually drain out, also the emissions produced from them contribute to global warming. For a sustainable future, these fossil fuels should be replaced with renewable and green energy sources. Sea waves are a gigantic and undiscovered vitality asset. The potential for extricating energy from waves is extensive. To trap this energy, wave energy converters (WEC) are needed. There is a need for increasing the energy output and decreasing the cost requirement of these existing WECs. This paper presents a method which uses prediction as a part of the control scheme to increase the energy efficiency of the floating-point absorber WECs. Kalman Filter is used for estimation, coupled with latching control in regular as well as irregular sea waves. Modelling and Simulation results for the same are also included.

  19. Floating point only SIMD instruction set architecture including compare, select, Boolean, and alignment operations

    Science.gov (United States)

    Gschwind, Michael K [Chappaqua, NY

    2011-03-01

    Mechanisms for implementing a floating point only single instruction multiple data instruction set architecture are provided. A processor is provided that comprises an issue unit, an execution unit coupled to the issue unit, and a vector register file coupled to the execution unit. The execution unit has logic that implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA). The floating point vector registers of the vector register file store both scalar and floating point values as vectors having a plurality of vector elements. The processor may be part of a data processing system.

  20. Area, and Power Performance Analysis of a Floating-Point Based Application on FPGAs

    National Research Council Canada - National Science Library

    Govindu, Gokul

    2003-01-01

    .... However the inevitable quantization effects and the complexity of converting the floating-point algorithm into a fixed point one, limit the use of fixed-point arithmetic for high precision embedded computing...

  1. Word Length Selection Method for Controller Implementation on FPGAs Using the VHDL-2008 Fixed-Point and Floating-Point Packages

    Directory of Open Access Journals (Sweden)

    Urriza I

    2010-01-01

    Full Text Available Abstract This paper presents a word length selection method for the implementation of digital controllers in both fixed-point and floating-point hardware on FPGAs. This method uses the new types defined in the VHDL-2008 fixed-point and floating-point packages. These packages allow customizing the word length of fixed and floating point representations and shorten the design cycle simplifying the design of arithmetic operations. The method performs bit-true simulations in order to determine the word length to represent the constant coefficients and the internal signals of the digital controller while maintaining the control system specifications. A mixed-signal simulation tool is used to simulate the closed loop system as a whole in order to analyze the impact of the quantization effects and loop delays on the control system performance. The method is applied to implement a digital controller for a switching power converter. The digital circuit is implemented on an FPGA, and the simulations are experimentally verified.

  2. Optimal Design of Fixed-Point and Floating-Point Arithmetic Units for Scientific Applications

    OpenAIRE

    Pongyupinpanich, Surapong

    2012-01-01

    The challenge in designing a floating-point arithmetic co-processor/processor for scientific and engineering applications is to improve the performance, efficiency, and computational accuracy of the arithmetic unit. The arithmetic unit should efficiently support several mathematical functions corresponding to scientific and engineering computation demands. Moreover, the computations should be performed as fast as possible with a high degree of accuracy. Thus, this thesis proposes algorithm, d...

  3. A Flexible VHDL Floating Point Module for Control Algorithm Implementation in Space Applications

    Science.gov (United States)

    Padierna, A.; Nicoleau, C.; Sanchez, J.; Hidalgo, I.; Elvira, S.

    2012-08-01

    The implementation of control loops for space applications is an area with great potential. However, the characteristics of this kind of systems, such as its wide dynamic range of numeric values, make inadequate the use of fixed-point algorithms.However, because the generic chips available for the treatment of floating point data are, in general, not qualified to operate in space environments and the possibility of using an IP module in a FPGA/ASIC qualified for space is not viable due to the low amount of logic cells available for these type of devices, it is necessary to find a viable alternative.For these reasons, in this paper a VHDL Floating Point Module is presented. This proposal allows the design and execution of floating point algorithms with acceptable occupancy to be implemented in FPGAs/ASICs qualified for space environments.

  4. Utilizing the Double-Precision Floating-Point Computing Power of GPUs for RSA Acceleration

    Directory of Open Access Journals (Sweden)

    Jiankuo Dong

    2017-01-01

    Full Text Available Asymmetric cryptographic algorithm (e.g., RSA and Elliptic Curve Cryptography implementations on Graphics Processing Units (GPUs have been researched for over a decade. The basic idea of most previous contributions is exploiting the highly parallel GPU architecture and porting the integer-based algorithms from general-purpose CPUs to GPUs, to offer high performance. However, the great potential cryptographic computing power of GPUs, especially by the more powerful floating-point instructions, has not been comprehensively investigated in fact. In this paper, we fully exploit the floating-point computing power of GPUs, by various designs, including the floating-point-based Montgomery multiplication/exponentiation algorithm and Chinese Remainder Theorem (CRT implementation in GPU. And for practical usage of the proposed algorithm, a new method is performed to convert the input/output between octet strings and floating-point numbers, fully utilizing GPUs and further promoting the overall performance by about 5%. The performance of RSA-2048/3072/4096 decryption on NVIDIA GeForce GTX TITAN reaches 42,211/12,151/5,790 operations per second, respectively, which achieves 13 times the performance of the previous fastest floating-point-based implementation (published in Eurocrypt 2009. The RSA-4096 decryption precedes the existing fastest integer-based result by 23%.

  5. On the design of a radix-10 online floating-point multiplier

    Science.gov (United States)

    McIlhenny, Robert D.; Ercegovac, Milos D.

    2009-08-01

    This paper describes an approach to design and implement a radix-10 online floating-point multiplier. An online approach is considered because it offers computational flexibility not available with conventional arithmetic. The design was coded in VHDL and compiled, synthesized, and mapped onto a Virtex 5 FPGA to measure cost in terms of LUTs (look-up-tables) as well as the cycle time and total latency. The routing delay which was not optimized is the major component in the cycle time. For a rough estimate of the cost/latency characteristics, our design was compared to a standard radix-2 floating-point multiplier of equivalent precision. The results demonstrate that even an unoptimized radix-10 online design is an attractive implementation alternative for FPGA floating-point multiplication.

  6. Generating and executing programs for a floating point single instruction multiple data instruction set architecture

    Science.gov (United States)

    Gschwind, Michael K

    2013-04-16

    Mechanisms for generating and executing programs for a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA) are provided. A computer program product comprising a computer recordable medium having a computer readable program recorded thereon is provided. The computer readable program, when executed on a computing device, causes the computing device to receive one or more instructions and execute the one or more instructions using logic in an execution unit of the computing device. The logic implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA), based on data stored in a vector register file of the computing device. The vector register file is configured to store both scalar and floating point values as vectors having a plurality of vector elements.

  7. Study on a New Steering Mechanism for Point-the-Bit Rotary Steerable System

    Directory of Open Access Journals (Sweden)

    Yuanzhi Li

    2014-02-01

    Full Text Available This paper presents a novel steering mechanism embedded in a point-the-bit rotary steerable system (RSS for oilfield exploitation. The new steering mechanism adopts a set of universal joints to alleviate the high alternative strain on drilling mandrel and employs a specially designed planetary gear small tooth number difference (PGSTD to achieve directional steering. Its principle and characteristics are explained and examined through a series of analyses. First, the eccentric displacement vector of the offset point on the drilling mandrel is formulated and kinematic solutions are established. Next, structural design for the new steering mechanism is addressed. Then, procedures and program architectures for simulating offset state of the drilling mandrel and motion trajectory of the whole steering mechanism are presented. After that, steering motion simulations of the new steering mechanism for both 2D and 3D well trajectories are then performed by combining LabVIEW and SolidWorks. Finally, experiments on the steering motion control of the new steering mechanism prototype are carried out. The simulations and experiments reveal that the steering performance of the new steering mechanism is satisfied. The research can provide good guidance for further research and engineering application of the point-the-bit RSS.

  8. Handwritten Digit Classification using 8-bit Floating Point based Convolutional Neural Networks

    DEFF Research Database (Denmark)

    Gallus, Michal

    Training of deep neural networks is often constrained by the available memory and computational power. This often causes it to run for weeks even when the underlying platform is employed with multiple GPUs. In order to speed up the training and reduce space complexity the paper presents an approach...

  9. Bit Error Rate Due to Misalignment of Earth Station Antenna Pointing to Satellite

    Directory of Open Access Journals (Sweden)

    Wahyu Pamungkas

    2010-04-01

    Full Text Available One problem causing reduction of energy in satellite communications system is the misalignment of earth station antenna pointing to satellite. Error in pointing would affect the quality of information signal to energy bit in earth station. In this research, error in pointing angle occurred only at receiver (Rx antenna, while the transmitter (Tx antennas precisely point to satellite. The research was conducted towards two satellites, namely TELKOM-1 and TELKOM-2. At first, measurement was made by directing Tx antenna precisely to satellite, resulting in an antenna pattern shown by spectrum analyzer. The output from spectrum analyzers is drawn with the right scale to describe swift of azimuth and elevation pointing angle towards satellite. Due to drifting from the precise pointing, it influenced the received link budget indicated by pattern antenna. This antenna pattern shows reduction of power level received as a result of pointing misalignment. As a conclusion, the increasing misalignment of pointing to satellite would affect in the reduction of received signal parameters link budget of down-link traffic.

  10. Beam-pointing error compensation method of phased array radar seeker with phantom-bit technology

    Directory of Open Access Journals (Sweden)

    Qiuqiu WEN

    2017-06-01

    Full Text Available A phased array radar seeker (PARS must be able to effectively decouple body motion and accurately extract the line-of-sight (LOS rate for target missile tracking. In this study, the real-time two-channel beam pointing error (BPE compensation method of PARS for LOS rate extraction is designed. The PARS discrete beam motion principium is analyzed, and the mathematical model of beam scanning control is finished. According to the principle of the antenna element shift phase, both the antenna element shift phase law and the causes of beam-pointing error under phantom-bit conditions are analyzed, and the effect of BPE caused by phantom-bit technology (PBT on the extraction accuracy of the LOS rate is examined. A compensation method is given, which includes coordinate transforms, beam angle margin compensation, and detector dislocation angle calculation. When the method is used, the beam angle margin in the pitch and yaw directions is calculated to reduce the effect of the missile body disturbance and to improve LOS rate extraction precision by compensating for the detector dislocation angle. The simulation results validate the proposed method.

  11. Towards better segmentation of large floating point 3D astronomical data sets : first results

    NARCIS (Netherlands)

    Moschini, Ugo; Teeninga, Paul; Wilkinson, Michael; Giese, Nadine; Punzo, Davide; van der Hulst, Jan M.; Trager, Scott

    2014-01-01

    In any image segmentation task, noise must be separated from the actual information and the relevant pixels grouped into objects of interest, on which measures can later be applied. This should be done efficiently on large astronomical surveys with floating point datasets with resolution of the

  12. Floating-point-based hardware accelerator of a beam phase-magnitude detector and filter for a beam phase control system in a heavy-ion synchrotron application

    International Nuclear Information System (INIS)

    Samman, F.A.; Pongyupinpanich Surapong; Spies, C.; Glesner, M.

    2012-01-01

    A hardware implementation of an adaptive phase and magnitude detector and filter of a beam-phase control system in a heavy ion synchrotron application is presented in this paper. The main components of the hardware are adaptive LMS (Least-Mean-Square) filters and phase and magnitude detectors. The phase detectors are implemented by using a CORDIC (Coordinate Rotation Digital Computer) algorithm based on 32-bit binary floating-point arithmetic data formats. The floating-point-based hardware is designed to improve the precision of the past hardware implementation that were based on fixed-point arithmetics. The hardware of the detector and the adaptive LMS filter have been implemented on a programmable logic device (FPGA) for hardware acceleration purpose. The ideal Matlab/Simulink model of the hardware and the VHDL model of the adaptive LMS filter and the phase and magnitude detector are compared. The comparison result shows that the output signal of the floating-point based adaptive FIR filter as well as the phase and magnitude detector agree with the expected output signal of the ideal Matlab/Simulink model. (authors)

  13. Improving Performance of Software Implemented Floating Point Addition

    DEFF Research Database (Denmark)

    Hindborg, Andreas Erik; Karlsson, Sven

    2011-01-01

    We outline and evaluate hardware extensions to an integer processor pipeline which allow IEEE 754 oating point, FP, addition to be eciently implemented in software. With a very moderate increase in hardware resources, our perfor- mance evaluation shows that, for a benchmark that executes 12.5% FP...... addition instructions, our approach exhibits a rel- ative slowdown of 3.38 to 15.15 as compared to dedicated hardware. This is a signicant improvement of pure software emulation which leads to relative slowdowns up to 45.33....

  14. An efficient parallel pseudorandom bit generator based

    Indian Academy of Sciences (India)

    In this paper, an asymmetric coupled map lattice (CML) combining sawtooth map as a local map is presented and its chaotic behaviours are analysed. Based on this asymmetric CML, a pseudorandom bit generator (PRBG) is proposed. The specific parameters of the system that make complicated floating-point computation ...

  15. Asymmetrical floating point array processors, their application to exploration and exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Geriepy, B L

    1983-01-01

    An asymmetrical floating point array processor is a special-purpose scientific computer which operates under asymmetrical control of a host computer. Although an array processor can receive fixed point input and produce fixed point output, its primary mode of operation is floating point. The first generation of array processors was oriented towards time series information. The next generation of array processors has proved much more versatile and their applicability ranges from petroleum reservoir simulation to speech syntheses. Array processors are becoming commonplace in mining, the primary usage being construction of grids-by usual methods or by kriging. The Australian mining community is among the world's leaders in regard to computer-assisted exploration and exploitation systems. Part of this leadership role must be providing guidance to computer vendors in regard to current and future requirements.

  16. Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results

    International Nuclear Information System (INIS)

    Brengle, T.A.; Maron, N.

    1980-01-01

    Results are presented of comparative timing tests made by running a typical FORTRAN physics simulation code on the following machines: DEC PDP-10 with KI processor; DEC PDP-10, KI processor, and FPS AP-190L; CDC 7600; and CRAY-1. Factors such as DMA overhead, code size for the AP-190L, and the relative utilization of floating point functional units for the different machines are discussed. 1 table

  17. Floating-point geometry: toward guaranteed geometric computations with approximate arithmetics

    Science.gov (United States)

    Bajard, Jean-Claude; Langlois, Philippe; Michelucci, Dominique; Morin, Géraldine; Revol, Nathalie

    2008-08-01

    Geometric computations can fail because of inconsistencies due to floating-point inaccuracy. For instance, the computed intersection point between two curves does not lie on the curves: it is unavoidable when the intersection point coordinates are non rational, and thus not representable using floating-point arithmetic. A popular heuristic approach tests equalities and nullities up to a tolerance ɛ. But transitivity of equality is lost: we can have A approx B and B approx C, but A not approx C (where A approx B means ||A - B|| < ɛ for A,B two floating-point values). Interval arithmetic is another, self-validated, alternative; the difficulty is to limit the swell of the width of intervals with computations. Unfortunately interval arithmetic cannot decide equality nor nullity, even in cases where it is decidable by other means. A new approach, developed in this paper, consists in modifying the geometric problems and algorithms, to account for the undecidability of the equality test and unavoidable inaccuracy. In particular, all curves come with a non-zero thickness, so two curves (generically) cut in a region with non-zero area, an inner and outer representation of which is computable. This last approach no more assumes that an equality or nullity test is available. The question which arises is: which geometric problems can still be solved with this last approach, and which cannot? This paper begins with the description of some cases where every known arithmetic fails in practice. Then, for each arithmetic, some properties of the problems they can solve are given. We end this work by proposing the bases of a new approach which aims to fulfill the geometric computations requirements.

  18. The laboratory information float, time-based competition, and point-of-care testing.

    Science.gov (United States)

    Friedman, B A

    1994-01-01

    A new term, the laboratory information float, should be substituted for turnaround-time when evaluating the performance of the clinical laboratory because it includes the time necessary to make test results both available (ready to use) and accessible (easy to use) to clinicians ordering tests. The laboratory information float can be greatly reduced simply by telescoping the analytic phase of laboratory testing into the preanalytic phase. Significant costs are incurred by such a change, some of which can be reduced by developing a mobile clinical laboratory (sometimes referred to as a "lab-on-a-slab" or "rolling thunder") to transport the analytic devices directly to patient care units. The mobile clinical laboratory should be equipped with an integrated personal computer that can communicate continuously with the host laboratory information system and achieve some semblance of continuous flow processing despite test performance in point-of-care venues. Equipping clinicians with palmtop computers will allow the mobile clinician to access test results and order tests on the run. Such devices can be easily configured to operate in a passive mode, accessing relevant information automatically instead of forcing clinicians to query the laboratory information system periodically for the test results necessary to render care to their patients. The laboratory information float of the year 2,000 will surely be measured in minutes through the judicious deployment of relevant technology such as mobile clinical laboratories and palmtop computers.

  19. The use of ZFP lossy floating point data compression in tornado-resolving thunderstorm simulations

    Science.gov (United States)

    Orf, L.

    2017-12-01

    In the field of atmospheric science, numerical models are used to produce forecasts of weather and climate and serve as virtual laboratories for scientists studying atmospheric phenomena. In both operational and research arenas, atmospheric simulations exploiting modern supercomputing hardware can produce a tremendous amount of data. During model execution, the transfer of floating point data from memory to the file system is often a significant bottleneck where I/O can dominate wallclock time. One way to reduce the I/O footprint is to compress the floating point data, which reduces amount of data saved to the file system. In this presentation we introduce LOFS, a file system developed specifically for use in three-dimensional numerical weather models that are run on massively parallel supercomputers. LOFS utilizes the core (in-memory buffered) HDF5 driver and includes compression options including ZFP, a lossy floating point data compression algorithm. ZFP offers several mechanisms for specifying the amount of lossy compression to be applied to floating point data, including the ability to specify the maximum absolute error allowed in each compressed 3D array. We explore different maximum error tolerances in a tornado-resolving supercell thunderstorm simulation for model variables including cloud and precipitation, temperature, wind velocity and vorticity magnitude. We find that average compression ratios exceeding 20:1 in scientifically interesting regions of the simulation domain produce visually identical results to uncompressed data in visualizations and plots. Since LOFS splits the model domain across many files, compression ratios for a given error tolerance can be compared across different locations within the model domain. We find that regions of high spatial variability (which tend to be where scientifically interesting things are occurring) show the lowest compression ratios, whereas regions of the domain with little spatial variability compress

  20. LDPC decoder with a limited-precision FPGA-based floating-point multiplication coprocessor

    Science.gov (United States)

    Moberly, Raymond; O'Sullivan, Michael; Waheed, Khurram

    2007-09-01

    Implementing the sum-product algorithm, in an FPGA with an embedded processor, invites us to consider a tradeoff between computational precision and computational speed. The algorithm, known outside of the signal processing community as Pearl's belief propagation, is used for iterative soft-decision decoding of LDPC codes. We determined the feasibility of a coprocessor that will perform product computations. Our FPGA-based coprocessor (design) performs computer algebra with significantly less precision than the standard (e.g. integer, floating-point) operations of general purpose processors. Using synthesis, targeting a 3,168 LUT Xilinx FPGA, we show that key components of a decoder are feasible and that the full single-precision decoder could be constructed using a larger part. Soft-decision decoding by the iterative belief propagation algorithm is impacted both positively and negatively by a reduction in the precision of the computation. Reducing precision reduces the coding gain, but the limited-precision computation can operate faster. A proposed solution offers custom logic to perform computations with less precision, yet uses the floating-point format to interface with the software. Simulation results show the achievable coding gain. Synthesis results help theorize the the full capacity and performance of an FPGA-based coprocessor.

  1. Recent advances in lossy compression of scientific floating-point data

    Science.gov (United States)

    Lindstrom, P.

    2017-12-01

    With a continuing exponential trend in supercomputer performance, ever larger data sets are being generated through numerical simulation. Bandwidth and storage capacity are, however, not keeping pace with this increase in data size, causing significant data movement bottlenecks in simulation codes and substantial monetary costs associated with archiving vast volumes of data. Worse yet, ever smaller fractions of data generated can be stored for further analysis, where scientists frequently rely on decimating or averaging large data sets in time and/or space. One way to mitigate these problems is to employ data compression to reduce data volumes. However, lossless compression of floating-point data can achieve only very modest size reductions on the order of 10-50%. We present ZFP and FPZIP, two state-of-the-art lossy compressors for structured floating-point data that routinely achieve one to two orders of magnitude reduction with little to no impact on the accuracy of visualization and quantitative data analysis. We provide examples of the use of such lossy compressors in climate and seismic modeling applications to effectively accelerate I/O and reduce storage requirements. We further discuss how the design decisions behind these and other compressors impact error distributions and other statistical and differential properties, including derived quantities of interest relevant to each science application.

  2. rpe v5: an emulator for reduced floating-point precision in large numerical simulations

    Science.gov (United States)

    Dawson, Andrew; Düben, Peter D.

    2017-06-01

    This paper describes the rpe (reduced-precision emulator) library which has the capability to emulate the use of arbitrary reduced floating-point precision within large numerical models written in Fortran. The rpe software allows model developers to test how reduced floating-point precision affects the result of their simulations without having to make extensive code changes or port the model onto specialized hardware. The software can be used to identify parts of a program that are problematic for numerical precision and to guide changes to the program to allow a stronger reduction in precision.The development of rpe was motivated by the strong demand for more computing power. If numerical precision can be reduced for an application under consideration while still achieving results of acceptable quality, computational cost can be reduced, since a reduction in numerical precision may allow an increase in performance or a reduction in power consumption. For simulations with weather and climate models, savings due to a reduction in precision could be reinvested to allow model simulations at higher spatial resolution or complexity, or to increase the number of ensemble members to improve predictions. rpe was developed with a particular focus on the community of weather and climate modelling, but the software could be used with numerical simulations from other domains.

  3. Parametric study of two-body floating-point wave absorber

    Science.gov (United States)

    Amiri, Atena; Panahi, Roozbeh; Radfar, Soheil

    2016-03-01

    In this paper, we present a comprehensive numerical simulation of a point wave absorber in deep water. Analyses are performed in both the frequency and time domains. The converter is a two-body floating-point absorber (FPA) with one degree of freedom in the heave direction. Its two parts are connected by a linear mass-spring-damper system. The commercial ANSYS-AQWA software used in this study performs well in considering validations. The velocity potential is obtained by assuming incompressible and irrotational flow. As such, we investigated the effects of wave characteristics on energy conversion and device efficiency, including wave height and wave period, as well as the device diameter, draft, geometry, and damping coefficient. To validate the model, we compared our numerical results with those from similar experiments. Our study results can clearly help to maximize the converter's efficiency when considering specific conditions.

  4. Bit-Grooming: Shave Your Bits with Razor-sharp Precision

    Science.gov (United States)

    Zender, C. S.; Silver, J.

    2017-12-01

    Lossless compression can reduce climate data storage by 30-40%. Further reduction requires lossy compression that also reduces precision. Fortunately, geoscientific models and measurements generate false precision (scientifically meaningless data bits) that can be eliminated without sacrificing scientifically meaningful data. We introduce Bit Grooming, a lossy compression algorithm that removes the bloat due to false-precision, those bits and bytes beyond the meaningful precision of the data.Bit Grooming is statistically unbiased, applies to all floating point numbers, and is easy to use. Bit-Grooming reduces geoscience data storage requirements by 40-80%. We compared Bit Grooming to competitors Linear Packing, Layer Packing, and GRIB2/JPEG2000. The other compression methods have the edge in terms of compression, but Bit Grooming is the most accurate and certainly the most usable and portable.Bit Grooming provides flexible and well-balanced solutions to the trade-offs among compression, accuracy, and usability required by lossy compression. Geoscientists could reduce their long term storage costs, and show leadership in the elimination of false precision, by adopting Bit Grooming.

  5. CFD Simulations of Floating Point Absorber Wave Energy Converter Arrays Subjected to Regular Waves

    Directory of Open Access Journals (Sweden)

    Brecht Devolder

    2018-03-01

    Full Text Available In this paper we use the Computational Fluid Dynamics (CFD toolbox OpenFOAM to perform numerical simulations of multiple floating point absorber wave energy converters (WECs arranged in a geometrical array configuration inside a numerical wave tank (NWT. The two-phase Navier-Stokes fluid solver is coupled with a motion solver to simulate the hydrodynamic flow field around the WECs and the wave-induced rigid body heave motion of each WEC within the array. In this study, the numerical simulations of a single WEC unit are extended to multiple WECs and the complexity of modelling individual floating objects close to each other in an array layout is tackled. The NWT is validated for fluid-structure interaction (FSI simulations by using experimental measurements for an array of two, five and up to nine heaving WECs subjected to regular waves. The validation is achieved by using mathematical models to include frictional forces observed during the experimental tests. For all the simulations presented, a good agreement is found between the numerical and the experimental results for the WECs’ heave motions, the surge forces on the WECs and the perturbed wave field around the WECs. As a result, our coupled CFD–motion solver proves to be a suitable and accurate toolbox for the study of fluid-structure interaction problems of WEC arrays.

  6. Vectorization of a classical trajectory code on a floating point systems, Inc. Model 164 attached processor.

    Science.gov (United States)

    Kraus, Wayne A; Wagner, Albert F

    1986-04-01

    A triatomic classical trajectory code has been modified by extensive vectorization of the algorithms to achieve much improved performance on an FPS 164 attached processor. Extensive timings on both the FPS 164 and a VAX 11/780 with floating point accelerator are presented as a function of the number of trajectories simultaneously run. The timing tests involve a potential energy surface of the LEPS variety and trajectories with 1000 time steps. The results indicate that vectorization results in timing improvements on both the VAX and the FPS. For larger numbers of trajectories run simultaneously, up to a factor of 25 improvement in speed occurs between VAX and FPS vectorized code. Copyright © 1986 John Wiley & Sons, Inc.

  7. Application of Modbus communication protocol and float-point display in MCS51 system

    International Nuclear Information System (INIS)

    Kong Xiangcheng; Liu Shaozhen

    2010-01-01

    As its widely opening and easy performance, Modbus communication protocol has a great advantage in field bus using. Details are given on a method to implement Modbus communication protocol based on MCS51 system, and the advantage of uVision integrated environment. The design realizes Modbus RTU mode communication, meanwhile the problem of synchronization in communication is solved. And float-point operation and display are achieved by format print. All of this are carried out under uVision integrated environment. The result approves that the response ratio of Modbus communication is 100%. The design shows the advantage of uVision integrated environment and MCS51 system. And also gives solution to the occasion where communication interface and low cost are required. (authors)

  8. Bit error rate analysis of free-space optical communication over general Malaga turbulence channels with pointing error

    KAUST Repository

    Alheadary, Wael Ghazy

    2016-12-24

    In this work, we present a bit error rate (BER) and achievable spectral efficiency (ASE) performance of a freespace optical (FSO) link with pointing errors based on intensity modulation/direct detection (IM/DD) and heterodyne detection over general Malaga turbulence channel. More specifically, we present exact closed-form expressions for adaptive and non-adaptive transmission. The closed form expressions are presented in terms of generalized power series of the Meijer\\'s G-function. Moreover, asymptotic closed form expressions are provided to validate our work. In addition, all the presented analytical results are illustrated using a selected set of numerical results.

  9. Evaluation of accelerated iterative x-ray CT image reconstruction using floating point graphics hardware

    International Nuclear Information System (INIS)

    Kole, J S; Beekman, F J

    2006-01-01

    Statistical reconstruction methods offer possibilities to improve image quality as compared with analytical methods, but current reconstruction times prohibit routine application in clinical and micro-CT. In particular, for cone-beam x-ray CT, the use of graphics hardware has been proposed to accelerate the forward and back-projection operations, in order to reduce reconstruction times. In the past, wide application of this texture hardware mapping approach was hampered owing to limited intrinsic accuracy. Recently, however, floating point precision has become available in the latest generation commodity graphics cards. In this paper, we utilize this feature to construct a graphics hardware accelerated version of the ordered subset convex reconstruction algorithm. The aims of this paper are (i) to study the impact of using graphics hardware acceleration for statistical reconstruction on the reconstructed image accuracy and (ii) to measure the speed increase one can obtain by using graphics hardware acceleration. We compare the unaccelerated algorithm with the graphics hardware accelerated version, and for the latter we consider two different interpolation techniques. A simulation study of a micro-CT scanner with a mathematical phantom shows that at almost preserved reconstructed image accuracy, speed-ups of a factor 40 to 222 can be achieved, compared with the unaccelerated algorithm, and depending on the phantom and detector sizes. Reconstruction from physical phantom data reconfirms the usability of the accelerated algorithm for practical cases

  10. Use of well points to determine the thickness and extent of floating product atop the water table

    International Nuclear Information System (INIS)

    Liikala, T.L.; Lewis, R.; Gilmore, T.; Hoffmann, H.

    1994-01-01

    The release of petroleum products to the ground water is a widespread problem. Conventional plume tracking techniques are to drill wells and measure product thickness and extent. In this study, well points were installed to rapidly and inexpensively determine the thickness and extent of floating product atop the water table. Spills and leaks of JP-4 have produced a discrete full layer atop the water table at one site at Eielson Air Force Base near Fairbanks, Alaska. The 0.2- to 1.3-foot-thick layer was identified in two ground water monitoring wells at a depth of approximately 10 feet. The layer is contained within unconsolidated glaciofluvial sands and gravels. A comprehensive assessment of the product thickness and extent was necessary for the site remedial investigation/feasibility study. The emplacement of additional monitoring wells was discouraged because of time and budget constraints. The fuel layer was delineated with 18 screened well points. The points consist of 2-inch-diameter galvanized steel pipe. The points were driven into the floating products with a hollow-stem auger rig sampling hammer. The product thickness was measured with an interface probe. The presence of floating product could be measured immediately after emplacement; the product thickness measurements typically stabilized within three days. The product thickness compared favorably with those measured in adjacent monitoring wells

  11. Analyzing logistic map pseudorandom number generators for periodicity induced by finite precision floating-point representation

    International Nuclear Information System (INIS)

    Persohn, K.J.; Povinelli, R.J.

    2012-01-01

    Highlights: ► A chaotic pseudorandom number generator (C-PRNG) poorly explores the key space. ► A C-PRNG is finite and periodic when implemented on a finite precision computer. ► We present a method to determine the period lengths of a C-PRNG. - Abstract: Because of the mixing and aperiodic properties of chaotic maps, such maps have been used as the basis for pseudorandom number generators (PRNGs). However, when implemented on a finite precision computer, chaotic maps have finite and periodic orbits. This manuscript explores the consequences finite precision has on the periodicity of a PRNG based on the logistic map. A comparison is made with conventional methods of generating pseudorandom numbers. The approach used to determine the number, delay, and period of the orbits of the logistic map at varying degrees of precision (3 to 23 bits) is described in detail, including the use of the Condor high-throughput computing environment to parallelize independent tasks of analyzing a large initial seed space. Results demonstrate that in terms of pathological seeds and effective bit length, a PRNG based on the logistic map performs exponentially worse than conventional PRNGs.

  12. Control electronic platform based on floating-point DSP and FPGA for a NPC multilevel back-to-back converter

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Francisco J.; Cobreces, Santiago; Bueno, Emilio J.; Hernandez, Alvaro; Mateos, Raul; Espinosa, Felipe [Department of Electronics, University of Alcala, Alcala de Henares, Madrid (Spain)

    2008-09-15

    Modern energy concepts as Distributed Power Generation are changing the appearance of electric distribution and transmission and challenging power electronics researchers, which try to develop new solutions of electronic controllers. The aim is to enable the implementation of new and more complex control algorithms to verify the last standards related to the grid energy quality for new power converters, and, also, for equipments which nowadays are operating. This paper presents the design, implementation and test of a novel real-time controller for a Neutral Point Clamped (NPC) (three-level) multilevel converter based on a floating-point Digital Signal Processor (DSP) and on a Field-Programmable Gate Array (FPGA), by operating in a cooperative way. Although the proposed system can be readily applied to any power electronic application, in this work, it is focused on the next system: a 150 kVA back-to-back three-level NPC Voltage Source Converter (VSC) for wind power applications. (author)

  13. The Coarse-Grained/Fine-Grained Logic Interface in FPGAs with Embedded Floating-Point Arithmetic Units

    Directory of Open Access Journals (Sweden)

    Chi Wai Yu

    2008-01-01

    Full Text Available This paper examines the interface between fine-grained and coarse-grained programmable logic in FPGAs. Specifically, it presents an empirical study that covers the location, pin arrangement, and interconnect between embedded floating point units (FPUs and the fine-grained logic fabric in FPGAs. It also studies this interface in FPGAs which contain both FPUs and embedded memories. The results show that (1 FPUs should have a square aspect ratio; (2 they should be positioned near the center of the FPGA; (3 their I/O pins should be arranged around all four sides of the FPU; (4 embedded memory should be located between the FPUs; and (5 connecting higher I/O density coarse-grained blocks increases the demand for routing resources. The hybrid FPGAs with embedded memory required 12% wider channels than the case where embedded memory is not used.

  14. Single-board 32-bit computer for the FASTBUS

    International Nuclear Information System (INIS)

    Kellner, R.; Blossom, J.M.; Hong, J.P.

    1985-01-01

    The Los Alamos National Laboratory is building a 32bit computer on a FASTBUS board. It will use the National Semiconductor 32032 chip set, including the demand-paged memory management, floating point slave processor and interrupt control chips. The board will support 4 megabytes of memory which can be accessed by the processor over an on-board execution bus at processor speeds and which can be accessed by the FASTBUS at 80 megabytes per second. A windowed, direct memory access mechanism allows transfers of up to all of the memory

  15. Hydrodynamics of triangular-grid arrays of floating point-absorber wave energy converters with inter-body and bottom slack-mooring connections

    Energy Technology Data Exchange (ETDEWEB)

    Vicente, Pedro C.; Falcao, Antonio F. de O.; Gato, Luiz M.C. [IDMEC, Instituto Superior Tecnico, Technical University of Lisbon, 1049-001 Lisboa (Portugal); Justino, Paulo A.P. [Laboratorio Nacional de Energia e Geologia, 1649-038 Lisboa (Portugal)

    2009-07-01

    It may be convenient that dense arrays of floating point absorbers are spread-moored to the sea bottom through only some of their elements (possibly located in the periphery), while the other array elements are prevented from drifting and colliding with each other by connections to adjacent elements. An array of identical floating point absorbers located at the grid points of an equilateral triangular grid is considered in the paper. A spread set of slack-mooring lines connect the peripheric floaters to the bottom. A weight is located at the centre of each triangle whose function is o pull the three floaters towards each other and keep the inter-body moorings lines under tension. The whole system - buoys, moorings and power take-off systems - is assumed linear, so that a frequency domain analysis may be employed. Hydrodynamic interference between the oscillating bodies is neglected. Equations are presented for a set of three identical point absorbers. This is then extended to more complex equilateral iriangular grid arrays. Results from numerical simulations, with regular and irregular waves, are presented for the motions and power absorption of hemispherical converters in arrays of three and seven elements and different mooring and power take-off parameters, and wave incidence angles. Comparisons are given with the unmoored and independently-moored buoy situations.

  16. 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 ...

  17. Collision Visualization of a Laser-Scanned Point Cloud of Streets and a Festival Float Model Used for the Revival of a Traditional Procession Route

    Science.gov (United States)

    Li, W.; Shigeta, K.; Hasegawa, K.; Li, L.; Yano, K.; Tanaka, S.

    2017-09-01

    Recently, laser-scanning technology, especially mobile mapping systems (MMSs), has been applied to measure 3D urban scenes. Thus, it has become possible to simulate a traditional cultural event in a virtual space constructed using measured point clouds. In this paper, we take the festival float procession in the Gion Festival that has a long history in Kyoto City, Japan. The city government plans to revive the original procession route that is narrow and not used at present. For the revival, it is important to know whether a festival float collides with houses, billboards, electric wires or other objects along the original route. Therefore, in this paper, we propose a method for visualizing the collisions of point cloud objects. The advantageous features of our method are (1) a see-through visualization with a correct depth feel that is helpful to robustly determine the collision areas, (2) the ability to visualize areas of high collision risk as well as real collision areas, and (3) the ability to highlight target visualized areas by increasing the point densities there.

  18. COLLISION VISUALIZATION OF A LASER-SCANNED POINT CLOUD OF STREETS AND A FESTIVAL FLOAT MODEL USED FOR THE REVIVAL OF A TRADITIONAL PROCESSION ROUTE

    Directory of Open Access Journals (Sweden)

    W. Li

    2017-09-01

    Full Text Available Recently, laser-scanning technology, especially mobile mapping systems (MMSs, has been applied to measure 3D urban scenes. Thus, it has become possible to simulate a traditional cultural event in a virtual space constructed using measured point clouds. In this paper, we take the festival float procession in the Gion Festival that has a long history in Kyoto City, Japan. The city government plans to revive the original procession route that is narrow and not used at present. For the revival, it is important to know whether a festival float collides with houses, billboards, electric wires or other objects along the original route. Therefore, in this paper, we propose a method for visualizing the collisions of point cloud objects. The advantageous features of our method are (1 a see-through visualization with a correct depth feel that is helpful to robustly determine the collision areas, (2 the ability to visualize areas of high collision risk as well as real collision areas, and (3 the ability to highlight target visualized areas by increasing the point densities there.

  19. Bit Grooming: statistically accurate precision-preserving quantization with compression, evaluated in the netCDF Operators (NCO, v4.4.8+)

    Science.gov (United States)

    Zender, Charles S.

    2016-09-01

    Geoscientific models and measurements generate false precision (scientifically meaningless data bits) that wastes storage space. False precision can mislead (by implying noise is signal) and be scientifically pointless, especially for measurements. By contrast, lossy compression can be both economical (save space) and heuristic (clarify data limitations) without compromising the scientific integrity of data. Data quantization can thus be appropriate regardless of whether space limitations are a concern. We introduce, implement, and characterize a new lossy compression scheme suitable for IEEE floating-point data. Our new Bit Grooming algorithm alternately shaves (to zero) and sets (to one) the least significant bits of consecutive values to preserve a desired precision. This is a symmetric, two-sided variant of an algorithm sometimes called Bit Shaving that quantizes values solely by zeroing bits. Our variation eliminates the artificial low bias produced by always zeroing bits, and makes Bit Grooming more suitable for arrays and multi-dimensional fields whose mean statistics are important. Bit Grooming relies on standard lossless compression to achieve the actual reduction in storage space, so we tested Bit Grooming by applying the DEFLATE compression algorithm to bit-groomed and full-precision climate data stored in netCDF3, netCDF4, HDF4, and HDF5 formats. Bit Grooming reduces the storage space required by initially uncompressed and compressed climate data by 25-80 and 5-65 %, respectively, for single-precision values (the most common case for climate data) quantized to retain 1-5 decimal digits of precision. The potential reduction is greater for double-precision datasets. When used aggressively (i.e., preserving only 1-2 digits), Bit Grooming produces storage reductions comparable to other quantization techniques such as Linear Packing. Unlike Linear Packing, whose guaranteed precision rapidly degrades within the relatively narrow dynamic range of values that

  20. FLOAT Project

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Aarup, Bendt

    The objective of the FLOAT project is to study the reliability of high-performance fibre-reinforced concrete, also known as Compact Reinforced Composite (CRC), for the floats of wave energy converters. In order to reach a commercial breakthrough, wave energy converters need to achieve a lower price...

  1. Entre grafos y bits

    Directory of Open Access Journals (Sweden)

    Carla Boserman

    2014-02-01

    Full Text Available Este texto se propone ahondar en las intersecciones de lo analógico y lo digital, en el encuentro de la baja y la alta tecnología. Tomando consciencia de la materialidad de ambas esferas para pensar desde ahí en objetos, prácticas de dibujo y documentación que puedan aportar otras formulaciones aplicables a métodos de investigación. Entre grafos y bits, diseccionaremos un objeto, el #relatograma, analizaremos su ecología y propondremos una reflexión acerca de su condición digital que genera paisajes por agregación #coreograma, explorando así su capacidad de ser reporte y aporte cognitivo. Between graphs and bits  Abstract This paper delves into the intersections of analogue and digital cultures, at the points at which low and high technology converge. While acknowledging the materiality of these two spheres, I aim to produce an enquiry into objects, drawings and documentation practices that can contribute to developing new research methods. Among graphs and bits, I will dissect one object: the #relatograma, in order to analyze its ecology and propose a critical reflection on its digital condition and its ability to produce aggregated landscapes, or what I define as #coreograma. I will thereby explore its ability to be share information and produce knowledge. Keywords: Material culture; research methods; digital objects; drawing; #relatograma.

  2. The bit slice micro-processor 'GESPRO' as a project in the UA2 experiment

    CERN Document Server

    Becam, C; Delanghe, J; Fest, H M; Lecoq, J; Martin, H; Mencik, M; MerkeI, B; Meyer, J M; Perrin, M; Plothow, H; Rampazzo, J P; Schittly, A

    1981-01-01

    The bit slice micro-processor GESPRO is a CAMAC module plugged into a standard Elliot system crate via which it communicates as a slave with its host computer. It has full control of CAMAC as a master unit. GESPRO is a 24 bit machine with multi-mode memory addressing capacity of 64K words. The micro-processor structure uses 5 buses including pipe-line registers to mask access time and 16 interrupt levels. The micro-program memory capacity is 2K (RAM) words of 48 bits each. A special hardwired module allows floating point, as well as integer, multiplication of 24*24 bits, result in 48 bits, in about 200 ns. This micro-processor could be used in the UA2 data acquisition chain and trigger system for the following tasks: (a) online data reduction, i.e. to read DURANDAL, process the information resulting in accepting or rejecting the event; (b) readout and analysis of the accepted data; (c) preprocess the data. The UA2 version of GESPRO is under construction, programs and micro-programs are under development. Hard...

  3. The bit slice micro-processor 'GESPRO' as a project in the UA2 experiment

    International Nuclear Information System (INIS)

    Becam, C.; Bernaudin, P.; Delanghe, J.; Mencik, M.; Merkel, B.; Plothow, H.; Fest, H.M.; Lecoq, J.; Martin, H.; Meyer, J.M.

    1981-01-01

    The bit slice micro-processor GESPRO, as it is proposed for use in the UA 2 data acquisition chain and trigger system, is a CAMAC module plugged into a standard Elliott System crate via which it communicates as a slave with its host computer (ND, DEC). It has full control of CAMAC as a master unit. GESPRO is a 24 bit machine (150 ns effective cycle time) with multi-mode memory addressing capacity of 64 K words. The micro-processor structure uses 5 busses including pipe-line registers to mask access time and 16 interrupt levels. The micro-program memory capacity is 2 K (RAM) words of 48 bits each. A special hardwired module allows floating point (as well as integer) multiplication of 24 x 24 bits, result in 48 bits, in about 200 ns. This micro-processor could be used in the UA2 data acquisition chain and trigger system for the following tasks: a) online data reduction, i.e. to read DURANDAL (fast ADC's = the hardware trigger in the experiment), process the information (effective mass calculation, etc.) resulting in accepting or rejecting the event. b) read out and analysis of the accepted data (collect statistical information). c) preprocess the data (calculation of pointers, address decoding, etc.). The UA2 version of GESPRO is under construction, programs and micro-programs are under development. Hardware and software will be tested with simulated data. First results are expected in about one year from now. (orig.)

  4. A 32-bit computer for large memory applications on the FASTBUS

    International Nuclear Information System (INIS)

    Kellner, R.; Blossom, J.M.; Hung, J.P.

    1985-01-01

    A FASTBUS based 32-bit computer is being built at Los Alamos National Laboratory for use in systems requiring large fast memory in the FASTBUS environment. A separate local execution bus allows data reduction to proceed concurrently with other FASTBUS operations. The computer, which can operate in either master or slave mode, includes the National Semiconductor NS32032 chip set with demand paged memory management, floating point slave processor, interrupt control unit, timers, and time-of-day clock. The 16.0 megabytes of random access memory are interleaved to allow windowed direct memory access on and off the FASTBUS at 80 megabytes per second

  5. Practical Relativistic Bit Commitment

    NARCIS (Netherlands)

    Lunghi, T.; Kaniewski, J.; Bussières, F.; Houlmann, R.; Tomamichel, M.; Wehner, S.D.C.; Zbinden, H

    2015-01-01

    Bit commitment is a fundamental cryptographic primitive in which Alice wishes to commit a secret bit to Bob. Perfectly secure bit commitment between two mistrustful parties is impossible through an asynchronous exchange of quantum information. Perfect security is, however, possible when Alice and

  6. Production and aging of paramagnetic point defects in P-doped floating zone silicon irradiated with high fluence 27 MeV electrons

    Science.gov (United States)

    Joita, A. C.; Nistor, S. V.

    2018-04-01

    Enhancing the long term stable performance of silicon detectors used for monitoring the position and flux of the particle beams in high energy physics experiments requires a better knowledge of the nature, stability, and transformation properties of the radiation defects created over the operation time. We report the results of an electron spin resonance investigation in the nature, transformation, and long term stability of the irradiation paramagnetic point defects (IPPDs) produced by high fluence (2 × 1016 cm-2), high energy (27 MeV) electrons in n-type, P-doped standard floating zone silicon. We found out that both freshly irradiated and aged (i.e., stored after irradiation for 3.5 years at 250 K) samples mainly contain negatively charged tetravacancy and pentavacancy defects in the first case and tetravacancy defects in the second one. The fact that such small cluster vacancy defects have not been observed by irradiation with low energy (below 5 MeV) electrons, but were abundantly produced by irradiation with neutrons, strongly suggests the presence of the same mechanism of direct formation of small vacancy clusters by irradiation with neutrons and high energy, high fluence electrons, in agreement with theoretical predictions. Differences in the nature and annealing properties of the IPPDs observed between the 27 MeV electrons freshly irradiated, and irradiated and aged samples were attributed to the presence of a high concentration of divacancies in the freshly irradiated samples, defects which transform during storage at 250 K through diffusion and recombination processes.

  7. Floating barrier

    Energy Technology Data Exchange (ETDEWEB)

    1968-05-06

    This floating barrier consists of relatively long elements which can be connected to form a practically continuous assembly. Each element consists of an inflatable tube with an apron of certain height, made of impregnated fabric which is resistant to ocean water and also to hydrocarbons. Means for connecting one element to the following one, and means for attaching ballast to the apron are also provided.

  8. Real-Time Spaceborne Synthetic Aperture Radar Float-Point Imaging System Using Optimized Mapping Methodology and a Multi-Node Parallel Accelerating Technique

    Science.gov (United States)

    Li, Bingyi; Chen, Liang; Yu, Wenyue; Xie, Yizhuang; Bian, Mingming; Zhang, Qingjun; Pang, Long

    2018-01-01

    With the development of satellite load technology and very large-scale integrated (VLSI) circuit technology, on-board real-time synthetic aperture radar (SAR) imaging systems have facilitated rapid response to disasters. A key goal of the on-board SAR imaging system design is to achieve high real-time processing performance under severe size, weight, and power consumption constraints. This paper presents a multi-node prototype system for real-time SAR imaging processing. We decompose the commonly used chirp scaling (CS) SAR imaging algorithm into two parts according to the computing features. The linearization and logic-memory optimum allocation methods are adopted to realize the nonlinear part in a reconfigurable structure, and the two-part bandwidth balance method is used to realize the linear part. Thus, float-point SAR imaging processing can be integrated into a single Field Programmable Gate Array (FPGA) chip instead of relying on distributed technologies. A single-processing node requires 10.6 s and consumes 17 W to focus on 25-km swath width, 5-m resolution stripmap SAR raw data with a granularity of 16,384 × 16,384. The design methodology of the multi-FPGA parallel accelerating system under the real-time principle is introduced. As a proof of concept, a prototype with four processing nodes and one master node is implemented using a Xilinx xc6vlx315t FPGA. The weight and volume of one single machine are 10 kg and 32 cm × 24 cm × 20 cm, respectively, and the power consumption is under 100 W. The real-time performance of the proposed design is demonstrated on Chinese Gaofen-3 stripmap continuous imaging. PMID:29495637

  9. Superconducting frustration bit

    International Nuclear Information System (INIS)

    Tanaka, Y.

    2014-01-01

    Highlights: • A frustration bit element is proposed for a conventional superconducting circuit. • It is composed of π-junctions. • It mimics the multiband superconductor. - Abstract: A basic design is proposed for a classical bit element of a superconducting circuit that mimics a frustrated multiband superconductor and is composed of an array of π-Josephson junctions (π-junction). The phase shift of π provides the lowest energy for one π-junction, but neither a π nor a zero phase shift gives the lowest energy for an assembly of π-junctions. There are two chiral states that can be used to store one bit information. The energy scale for reading and writing to memory is of the same order as the junction energy, and is thus in the same order of the driving energy of the circuit. In addition, random access is also possible

  10. Acquisition and Retaining Granular Samples via a Rotating Coring Bit

    Science.gov (United States)

    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

  11. 32-Bit FASTBUS computer

    International Nuclear Information System (INIS)

    Blossom, J.M.; Hong, J.P.; Kellner, R.G.

    1985-01-01

    Los Alamos National Laboratory is building a 32-bit FASTBUS computer using the NATIONAL SEMICONDUCTOR 32032 central processing unit (CPU) and containing 16 million bytes of memory. The board can act both as a FASTBUS master and as a FASTBUS slave. It contains a custom direct memory access (DMA) channel which can perform 80 million bytes per second block transfers across the FASTBUS

  12. Fixed-point image orthorectification algorithms for reduced computational cost

    Science.gov (United States)

    French, Joseph Clinton

    Imaging systems have been applied to many new applications in recent years. With the advent of low-cost, low-power focal planes and more powerful, lower cost computers, remote sensing applications have become more wide spread. Many of these applications require some form of geolocation, especially when relative distances are desired. However, when greater global positional accuracy is needed, orthorectification becomes necessary. Orthorectification is the process of projecting an image onto a Digital Elevation Map (DEM), which removes terrain distortions and corrects the perspective distortion by changing the viewing angle to be perpendicular to the projection plane. Orthorectification is used in disaster tracking, landscape management, wildlife monitoring and many other applications. However, orthorectification is a computationally expensive process due to floating point operations and divisions in the algorithm. To reduce the computational cost of on-board processing, two novel algorithm modifications are proposed. One modification is projection utilizing fixed-point arithmetic. Fixed point arithmetic removes the floating point operations and reduces the processing time by operating only on integers. The second modification is replacement of the division inherent in projection with a multiplication of the inverse. The inverse must operate iteratively. Therefore, the inverse is replaced with a linear approximation. As a result of these modifications, the processing time of projection is reduced by a factor of 1.3x with an average pixel position error of 0.2% of a pixel size for 128-bit integer processing and over 4x with an average pixel position error of less than 13% of a pixel size for a 64-bit integer processing. A secondary inverse function approximation is also developed that replaces the linear approximation with a quadratic. The quadratic approximation produces a more accurate approximation of the inverse, allowing for an integer multiplication calculation

  13. Quantum dynamics of quantum bits

    International Nuclear Information System (INIS)

    Nguyen, Bich Ha

    2011-01-01

    The theory of coherent oscillations of the matrix elements of the density matrix of the two-state system as a quantum bit is presented. Different calculation methods are elaborated in the case of a free quantum bit. Then the most appropriate methods are applied to the study of the density matrices of the quantum bits interacting with a classical pumping radiation field as well as with the quantum electromagnetic field in a single-mode microcavity. The theory of decoherence of a quantum bit in Markovian approximation is presented. The decoherence of a quantum bit interacting with monoenergetic photons in a microcavity is also discussed. The content of the present work can be considered as an introduction to the study of the quantum dynamics of quantum bits. (review)

  14. Smart BIT/TSMD Integration

    Science.gov (United States)

    1991-12-01

    integracion . Smart BIT/TSMD provides Rome Laboratory with a laboratory testbed to evaluate and assess the individual characteristics as well as the integration...that assessment. These windows are color-keyed to tie together multiple windows for the same Smart BIT techniques. The display of the neural net- work... Multiple accelerometer icons of any type may therefore be placed (non-overlapping) in the accelerometer Time Line region. The BIT Time Line Editor allows

  15. Bearing Capacity of Floating Ice Sheets under Short-Term Loads: Over-Sea-Ice Traverse from McMurdo Station to Marble Point

    Science.gov (United States)

    2015-01-01

    under Short-Term Loads Over-Sea-Ice Traverse from McMurdo Station to Marble Point Co ld R eg io ns R es ea rc h an d En gi ne er in g La bo ra...Traverse from McMurdo Station to Marble Point Jason C. Weale and Devinder S. Sodhi Cold Regions Research and Engineering Laboratory (CRREL) U.S...Division of Polar Programs operates an over-sea-ice traverse from McMurdo Station to rou- tinely resupply Marble Point Camp. The traverse requires that

  16. Floating offshore turbines

    DEFF Research Database (Denmark)

    Tande, John Olav Giæver; Merz, Karl; Schmidt Paulsen, Uwe

    2014-01-01

    metric of energy production per unit steel mass. Floating offshore wind turbines represent a promising technology. The successful operation of HyWind and WindFloat in full scale demonstrates a well advanced technology readiness level, where further development will go into refining the concepts, cost...

  17. Superconducting quantum bits

    International Nuclear Information System (INIS)

    Mooij, Hans

    2005-01-01

    Superconducting devices can be used to explore the boundaries between the quantum and classical worlds, and could also have applications in quantum information. The quantum world looks very different to the ordinary world. A quantum particle can, for instance, be in two places simultaneously, while its speed and position cannot both be measured with complete accuracy at the same time. Moreover, if its mass is small enough, a quantum particle can tunnel through energy barriers that its classical counterparts could never cross. Physicists are comfortable with the use of quantum mechanics to describe atomic and subatomic particles. However, in recent years we have discovered that micron-sized objects that have been produced using standard semiconductor-fabrication techniques - objects that are small on everyday scales but large compared with atoms - can also behave as quantum particles. These artificial quantum objects might one day be used as 'quantum bits' in a quantum computer that could perform certain computational tasks much faster than any classical computing device. Before then, however, these devices will allow us to explore the interface between the quantum and classical worlds, and to study how interactions with external degrees of freedom lead to a gradual disappearance of quantum behaviour. (U.K.)

  18. 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 digit...... which can have the value 0 or 1. Bit preservation must ensure that the bits remain intact and readable in the future, but bit preservation is not concerned with how bits can be interpreted as e.g. an image. A holistic approach to bit preservation includes aspects that influence the final choice of a bit...... a holistic approach and include aspects of digital representation, confidentiality, availability, bit safety and costs when defining requirements for the bit preservation. Analysis of such requirements and choice of the final bit preservation solution can be supported by the three main results presented...

  19. Bilateral Floating Hip and Floating Knee: a Rare Complex Injury ...

    African Journals Online (AJOL)

    We report a rare complex injury of a 45-year-old man who sustained a bilateral floating hip and floating knee and hospitalised in our service six days after a traffic accident. The floating knees were open type III and II of Cauchoix score in phase of suppuration. He also presented with a floating ankle on the right side.

  20. FLOAT Project - Task 1

    DEFF Research Database (Denmark)

    Marchalot, Tanguy; Kofoed, Jens Peter; Sørensen, Eigil V.

    .com, 2011). CRC floats could be a very cost-effective technology with enhanced loading capacity and environmental resistance, and very low maintenance requirements, affecting directly the final energy price. The project involves DEXA Wave Energy Ltd, Wave Star A/S, Aalborg University and Hi-Con A......The objective of the FLOAT project is to study the reliability of high-performance fibre-reinforced concrete, also known as Compact Reinforced Composite (CRC), for the floats of wave energy converters. In order to reach commercial breakthrough, wave energy converters need to achieve a lower price...

  1. Micromechanisms with floating pivot

    Science.gov (United States)

    Garcia, Ernest J.

    2001-03-06

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use floating pivot structures to relieve some of the problems encountered in the use of solid flexible pivots.

  2. Floating polygon soup

    OpenAIRE

    Colleu , Thomas; Morin , Luce; Pateux , Stéphane; Labit , Claude

    2011-01-01

    International audience; This paper presents a new representation called floating polygon soup for applications like 3DTV and FTV (Free Viewpoint Television). This representation is based on 3D polygons and takes as input MVD data. It extends the previously proposed polygon soup representation which is appropriate for both compression, transmission and rendering stages. The floating polygon soup conserves these advantages while also taking into account misalignments at the view synthesis stage...

  3. String bit models for superstring

    International Nuclear Information System (INIS)

    Bergman, O.; Thorn, C.B.

    1995-01-01

    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 - 2) + 1 dimensional space-time. This means that Poincare invariance is reduced to the Galilei subgroup in D - 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

  4. 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.

  5. 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.

  6. Bit-Blasting ACL2 Theorems

    Directory of Open Access Journals (Sweden)

    Sol Swords

    2011-10-01

    Full Text Available Interactive theorem proving requires a lot of human guidance. Proving a property involves (1 figuring out why it holds, then (2 coaxing the theorem prover into believing it. Both steps can take a long time. We explain how to use GL, a framework for proving finite ACL2 theorems with BDD- or SAT-based reasoning. This approach makes it unnecessary to deeply understand why a property is true, and automates the process of admitting it as a theorem. We use GL at Centaur Technology to verify execution units for x86 integer, MMX, SSE, and floating-point arithmetic.

  7. Bit-string scattering theory

    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.

  8. Bit-string scattering theory

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1990-01-01

    We construct discrete space-time coordinates separated by the Lorentz-invariant intervals h/mc in space and h/mc 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 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 πN 2 ) 2 = (2m N /m π ) 2 - 1. 21 refs., 1 fig

  9. Offshore floating windmills

    International Nuclear Information System (INIS)

    1993-10-01

    The aim was to produce a general survey of the profitability of establishing floating offshore wind turbine arrays and to compare this with the cost and profitability of constructing offshore arrays with fixed foundations and arrays located on land sites. Aspects of design in all cases are described, also into relation to the special demands placed on dimensioning in relation to the types of location and foundation. The costs of the offshore arrays are evaluated in relation to capacity under conditions in Danish waters. The advantage of floating arrays is that they can be placed far out to sea where they can not be seen from the coast and thus not be considered to spoil the marine view. But as the water gets deeper the cost of floating foundations rises. It was found that it would not be technologically profitable to establish floating arrays at a depth of less than 30 - 40 meters which means that only the outer Danish waters can be taken into consideration. For depths of up to 70 meters, individual floating bases are more expensive than fixed ones but would be cheaper if a number of windmills could share the same anchor. For depths of more than 70 meters floating foundations would be the cheapest. The cost is dependent on the depth and distance from the coast and also on wind conditions. The main conclusion is that currently the cost of establishing wind turbine arrays in deeper outer waters on floating foundations is comparable to that of arrays sited at inner waters on solid foundations placed on the sea bed. (AB) (20 refs.)

  10. 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...

  11. Cheat Sensitive Quantum Bit Commitment

    OpenAIRE

    Hardy, Lucien; Kent, Adrian

    1999-01-01

    We define cheat sensitive cryptographic protocols between mistrustful parties as protocols which guarantee that, if either cheats, the other has some nonzero probability of detecting the cheating. We give an example of an unconditionally secure cheat sensitive non-relativistic bit commitment protocol which uses quantum information to implement a task which is classically impossible; we also describe a simple relativistic protocol.

  12. Cheat sensitive quantum bit commitment.

    Science.gov (United States)

    Hardy, Lucien; Kent, Adrian

    2004-04-16

    We define cheat sensitive cryptographic protocols between mistrustful parties as protocols which guarantee that, if either cheats, the other has some nonzero probability of detecting the cheating. We describe an unconditionally secure cheat sensitive nonrelativistic bit commitment protocol which uses quantum information to implement a task which is classically impossible; we also describe a simple relativistic protocol.

  13. Compound floating pivot micromechanisms

    Science.gov (United States)

    Garcia, Ernest J.

    2001-04-24

    A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

  14. The floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

    2007-01-01

    When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

  15. Method of making imbalanced compensated drill bit

    International Nuclear Information System (INIS)

    Brett, J.F.; Warren, T.M.

    1991-01-01

    This patent describes a method for making a drill bit of the type having a bearing zone on a side portion of a bit body and a cutting zone with cutters mounted on the bit body. It comprises: mounting a preselected number of cutters within the cutting zone on the bit body; generating a model of the geometry of the bit body and cutters mounted thereon; calculating the imbalance force which would occur in the bit body under defined drilling parameters; using the imbalance force and model to calculate the position of at least one additional cutter which when mounted within the cutting zone on the bit body in the calculated position would create a net imbalance force directed towards the bearing zone; and mounting an additional cutter within the cutting zone on the bit body in the position so calculated

  16. 24-Hour Relativistic Bit Commitment.

    Science.gov (United States)

    Verbanis, Ephanielle; Martin, Anthony; Houlmann, Raphaël; Boso, Gianluca; Bussières, Félix; Zbinden, Hugo

    2016-09-30

    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.

  17. Float level indicator

    International Nuclear Information System (INIS)

    Grishchuk, M.Kh.; Laptev, A.G.; Pashkov, V.A.

    1980-01-01

    Specially developed level indicator is suggested with differential to-transformer converter of the float motion, operating in line with a movable electronic block, intended for indicating the level of the dissociating nitrogen tetroxide liquid phase. On the basis of the indicator elements the device is realized to measure the time of calibrated volume fillino. in by liquid nitrogen tetroxide in steady state operation of the experimental bench-marks [ru

  18. Bit-coded regular expression parsing

    DEFF Research Database (Denmark)

    Nielsen, Lasse; Henglein, Fritz

    2011-01-01

    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...

  19. The floating knee

    DEFF Research Database (Denmark)

    Muñoz Vives, Josep; Bel, Jean-Christophe; Capel Agundez, Arantxa

    2016-01-01

    In 1975, Blake and McBryde established the concept of 'floating knee' to describe ipsilateral fractures of the femur and tibia.1This combination is much more than a bone lesion; the mechanism is usually a high-energy trauma in a patient with multiple injuries and a myriad of other lesions...... fixation when both fractures (femoral and tibial) are extra-articular.Plates are the 'standard of care' in cases with articular fractures.A combination of implants are required by 40% of floating knees.Associated ligamentous and meniscal lesions are common, but may be irrelevant in the case of an intra......-articular fracture which gives the worst prognosis for this type of lesion. Cite this article: Muñoz Vives K, Bel J-C, Capel Agundez A, Chana Rodríguez F, Palomo Traver J, Schultz-Larsen M, Tosounidis, T. The floating knee.EFORT Open Rev2016;1:375-382. DOI: 10.1302/2058-5241.1.000042....

  20. Spectral analysis of Floating Car Data

    OpenAIRE

    Gössel, F.; Michler, E.; Wrase, B.

    2003-01-01

    Floating Car Data (FCD) are one important data source in traffic telematic systems. The original variable in these systems is the vehicle velocity. The paper analyses the measured value “vehicle velocity" by methods of information technology. Consequences for processing, transmission and storage of FCD under condition of limited resources are discussed. Starting point of the investigation is the analysis of spectral characteristics of velocity-time-profiles. The spectra are determined by...

  1. Insecurity of imperfect quantum bit seal

    International Nuclear Information System (INIS)

    Chau, H.F.

    2006-01-01

    Quantum bit seal is a way to encode a classical bit quantum mechanically so that everyone can obtain non-zero information on the value of the bit. Moreover, such an attempt should have a high chance of being detected by an authorized verifier. Surely, a reader looks for a way to get the maximum amount of information on the sealed bit and at the same time to minimize her chance of being caught. And a verifier picks a sealing scheme that maximizes his chance of detecting any measurement of the sealed bit. Here, I report a strategy that passes all measurement detection procedures at least half of the time for all quantum bit sealing schemes. This strategy also minimizes a reader's chance of being caught under a certain scheme. In this way, I extend the result of Bechmann-Pasquinucci et al. by proving that quantum seal is insecure in the case of imperfect sealed bit recovery

  2. Cost of remembering a bit of information

    Science.gov (United States)

    Chiuchiù; , D.; López-Suárez, M.; Neri, I.; Diamantini, M. C.; Gammaitoni, L.

    2018-05-01

    In 1961, Landauer [R. Landauer, IBM J. Res. Develop. 5, 183 (1961), 10.1147/rd.53.0183] pointed out that resetting a binary memory requires a minimum energy of kBT ln(2 ) . However, once written, any memory is doomed to lose its content if no action is taken. To avoid memory losses, a refresh procedure is periodically performed. We present a theoretical model and an experiment on a microelectromechanical system to evaluate the minimum energy required to preserve one bit of information over time. Two main conclusions are drawn: (i) in principle, the energetic cost to preserve information for a fixed time duration with a given error probability can be arbitrarily reduced if the refresh procedure is performed often enough, and (ii) the Heisenberg uncertainty principle sets an upper bound on the memory lifetime.

  3. Ipsilateral Floating Hip and Floating Knee – A Rare Entity

    Directory of Open Access Journals (Sweden)

    Yashavantha Kumar

    2013-04-01

    Full Text Available Introduction: Ipsilateral floating hip and floating knee are very rare injuries. These injuries so uncommon that only three cases of similar kind have been reported. These injuries are due to high velocity injuries following motor vehicle accidents. Management of such complex injuries is a challenging task even in experienced hands as there are no standard treatment guidelines for such fractures. Case Report: We hereby report a 20 yr old male who sustained ipsilateral floating hip and ipsilateral floating knee injuries following motor vehicle accident. Patient was stabilized initially and later taken up for surgery. Patient was treated with interlocking nail for femur and tibia in the same sitting whereas acetabulam fracture was managed conservatively. At five months all the fractures united well with restoration of good range of motion in both hip and knee. Conclusion: Ipsilateral floating knee and floating hip are very rare injuries seen following high velocity motor vehicle accidents. There are no standard guidelines for treatment of those fractures as only a few cases of similar kind have been reported in literature. Early fixation and aggressive mobilization ensures fracture union and fewer complications. Keywords: Floating hip, Floating Knee, Ipsilateral.

  4. Mourning in Bits and Stone

    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......, 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...... 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....

  5. In bits, bytes and stone

    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...... the respondents and interviewees are engaged with a prototype design that encompasses digitally enhanced experiences and interactions regarding mourning, memory and remembrance. The design is situated in a traditional public place of death, the Almen Cemetery of Aalborg in Denmark....

  6. FastBit Reference Manual

    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.

  7. A Methodology for Rapid Prototyping Peak-Constrained Least-Squares Bit-Serial Finite Impulse Response Filters in FPGAs

    Directory of Open Access Journals (Sweden)

    Alex Carreira

    2003-05-01

    Full Text Available Area-efficient peak-constrained least-squares (PCLS bit-serial finite impulse response (FIR filter implementations can be rapidly prototyped in field programmable gate arrays (FPGA with the methodology presented in this paper. Faster generation of the FPGA configuration bitstream is possible with a new application-specific mapping and placement method that uses JBits to avoid conventional general-purpose mapping and placement tools. JBits is a set of Java classes that provide an interface into the Xilinx Virtex FPGA configuration bitstream, allowing the user to generate new configuration bitstreams. PCLS coefficient generation allows passband-to-stopband energy ratio (PSR performance to be traded for a reduction in the filter's hardware cost without altering the minimum stopband attenuation. Fixed-point coefficients that meet the frequency response and hardware cost specifications can be generated with the PCLS method. It is not possible to meet these specifications solely by the quantization of floating-point coefficients generated in other methods.

  8. 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.

  9. A wavelet-based ECG delineation algorithm for 32-bit integer online processing.

    Science.gov (United States)

    Di Marco, Luigi Y; Chiari, Lorenzo

    2011-04-03

    Since the first well-known electrocardiogram (ECG) delineator based on Wavelet Transform (WT) presented by Li et al. in 1995, a significant research effort has been devoted to the exploitation of this promising method. Its ability to reliably delineate the major waveform components (mono- or bi-phasic P wave, QRS, and mono- or bi-phasic T wave) would make it a suitable candidate for efficient online processing of ambulatory ECG signals. Unfortunately, previous implementations of this method adopt non-linear operators such as root mean square (RMS) or floating point algebra, which are computationally demanding. This paper presents a 32-bit integer, linear algebra advanced approach to online QRS detection and P-QRS-T waves delineation of a single lead ECG signal, based on WT. The QRS detector performance was validated on the MIT-BIH Arrhythmia Database (sensitivity Se = 99.77%, positive predictive value P+ = 99.86%, on 109010 annotated beats) and on the European ST-T Database (Se = 99.81%, P+ = 99.56%, on 788050 annotated beats). The ECG delineator was validated on the QT Database, showing a mean error between manual and automatic annotation below 1.5 samples for all fiducial points: P-onset, P-peak, P-offset, QRS-onset, QRS-offset, T-peak, T-offset, and a mean standard deviation comparable to other established methods. The proposed algorithm exhibits reliable QRS detection as well as accurate ECG delineation, in spite of a simple structure built on integer linear algebra.

  10. Floating Silicon Method

    Energy Technology Data Exchange (ETDEWEB)

    Kellerman, Peter

    2013-12-21

    The Floating Silicon Method (FSM) project at Applied Materials (formerly Varian Semiconductor Equipment Associates), has been funded, in part, by the DOE under a “Photovoltaic Supply Chain and Cross Cutting Technologies” grant (number DE-EE0000595) for the past four years. The original intent of the project was to develop the FSM process from concept to a commercially viable tool. This new manufacturing equipment would support the photovoltaic industry in following ways: eliminate kerf losses and the consumable costs associated with wafer sawing, allow optimal photovoltaic efficiency by producing high-quality silicon sheets, reduce the cost of assembling photovoltaic modules by creating large-area silicon cells which are free of micro-cracks, and would be a drop-in replacement in existing high efficiency cell production process thereby allowing rapid fan-out into the industry.

  11. Factorization of a 512-bit RSA modulus

    NARCIS (Netherlands)

    S.H. Cavallar; W.M. Lioen (Walter); H.J.J. te Riele (Herman); B. Dodson; A.K. Lenstra (Arjen); P.L. Montgomery; B. Murphy

    2000-01-01

    textabstractOn August 22, 1999, we completed the factorization of the 512--bit 155--digit number RSA--155 with the help of the Number Field Sieve factoring method (NFS). This is a new record for factoring general numbers. Moreover, 512--bit RSA keys are frequently used for the protection of

  12. Efficient Bit-to-Symbol Likelihood Mappings

    Science.gov (United States)

    Moision, Bruce E.; Nakashima, Michael A.

    2010-01-01

    This innovation is an efficient algorithm designed to perform bit-to-symbol and symbol-to-bit likelihood mappings that represent a significant portion of the complexity of an error-correction code decoder for high-order constellations. Recent implementation of the algorithm in hardware has yielded an 8- percent reduction in overall area relative to the prior design.

  13. Hey! A Mosquito Bit Me! (For Kids)

    Science.gov (United States)

    ... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... Español Hey! A Mosquito Bit Me! KidsHealth / For Kids / Hey! A Mosquito Bit Me! Print en español ¡ ...

  14. High bit depth infrared image compression via low bit depth codecs

    DEFF Research Database (Denmark)

    Belyaev, Evgeny; Mantel, Claire; Forchhammer, Søren

    2017-01-01

    images via 8 bit depth codecs in the following way. First, an input 16 bit depth image is mapped into 8 bit depth images, e.g., the first image contains only the most significant bytes (MSB image) and the second one contains only the least significant bytes (LSB image). Then each image is compressed.......264/AVC codecs, which are usually available in efficient implementations, and compare their rate-distortion performance with JPEG2000, JPEG-XT and H.265/HEVC codecs supporting direct compression of infrared images in 16 bit depth format. A preliminary result shows that two 8 bit H.264/AVC codecs can...

  15. Control development for floating wind

    International Nuclear Information System (INIS)

    Savenije, Feike; Peeringa, Johan

    2014-01-01

    Control of a floating wind turbine has proven to be challenging, but essential for lowering the cost of floating wind energy. Topic of a recent joint R and D project by GustoMSC, MARIN and ECN, is the concept design and verification with coupled simulations and model tests of the GustoMSC Tri-Floater. Only using an integral design approach, including mooring and control design, a cost effective system can be obtained. In this project, ECN developed a general floating wind turbine control strategy and applied this in a case study to the GustoMSC Tri-Floater and the OC3Hywind spar, both equipped with the NREL 5MW RWT. The designed controller ensures stable operation, while maintaining proper speed and power regulation. The motions of the floating support are reduced and substantial load reduction has been achieved

  16. Large floating structures technological advances

    CERN Document Server

    Wang, BT

    2015-01-01

    This book surveys key projects that have seen the construction of large floating structures or have attained detailed conceptual designs. This compilation of key floating structures in a single volume captures the innovative features that mark the technological advances made in this field of engineering, and will provide a useful reference for ideas, analysis, design, and construction of these unique and emerging urban projects to offshore and marine engineers, urban planners, architects and students.

  17. Floating wind turbine system

    Science.gov (United States)

    Viterna, Larry A. (Inventor)

    2009-01-01

    A floating wind turbine system with a tower structure that includes at least one stability arm extending therefrom and that is anchored to the sea floor with a rotatable position retention device that facilitates deep water installations. Variable buoyancy for the wind turbine system is provided by buoyancy chambers that are integral to the tower itself as well as the stability arm. Pumps are included for adjusting the buoyancy as an aid in system transport, installation, repair and removal. The wind turbine rotor is located downwind of the tower structure to allow the wind turbine to follow the wind direction without an active yaw drive system. The support tower and stability arm structure is designed to balance tension in the tether with buoyancy, gravity and wind forces in such a way that the top of the support tower leans downwind, providing a large clearance between the support tower and the rotor blade tips. This large clearance facilitates the use of articulated rotor hubs to reduced damaging structural dynamic loads. Major components of the turbine can be assembled at the shore and transported to an offshore installation site.

  18. Electrically floating, near vertical incidence, skywave antenna

    Science.gov (United States)

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  19. Wave attenuation charcteristics of tethered float system

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.

    incident wave height transmitted wave height G wave number float mass number of rows of floats drag power transmitted wave power incident wave power 111 112 P. Vethamony float radius wave period time velocity and acceleration of fluid... particles, respectively wave attenuation in percentage displacement, velocity and acceleration of float, respectively amplitude of float displacement added mass damping coefficient fluid particle displacement amplitude of fluid particle displacement...

  20. Is a 4-bit synaptic weight resolution enough? - constraints on enabling spike-timing dependent plasticity in neuromorphic hardware.

    Science.gov (United States)

    Pfeil, Thomas; Potjans, Tobias C; Schrader, Sven; Potjans, Wiebke; Schemmel, Johannes; Diesmann, Markus; Meier, Karlheinz

    2012-01-01

    Large-scale neuromorphic hardware systems typically bear the trade-off between detail level and required chip resources. Especially when implementing spike-timing dependent plasticity, reduction in resources leads to limitations as compared to floating point precision. By design, a natural modification that saves resources would be reducing synaptic weight resolution. In this study, we give an estimate for the impact of synaptic weight discretization on different levels, ranging from random walks of individual weights to computer simulations of spiking neural networks. The FACETS wafer-scale hardware system offers a 4-bit resolution of synaptic weights, which is shown to be sufficient within the scope of our network benchmark. Our findings indicate that increasing the resolution may not even be useful in light of further restrictions of customized mixed-signal synapses. In addition, variations due to production imperfections are investigated and shown to be uncritical in the context of the presented study. Our results represent a general framework for setting up and configuring hardware-constrained synapses. We suggest how weight discretization could be considered for other backends dedicated to large-scale simulations. Thus, our proposition of a good hardware verification practice may rise synergy effects between hardware developers and neuroscientists.

  1. BitPAl: a bit-parallel, general integer-scoring sequence alignment algorithm.

    Science.gov (United States)

    Loving, Joshua; Hernandez, Yozen; Benson, Gary

    2014-11-15

    Mapping of high-throughput sequencing data and other bulk sequence comparison applications have motivated a search for high-efficiency sequence alignment algorithms. The bit-parallel approach represents individual cells in an alignment scoring matrix as bits in computer words and emulates the calculation of scores by a series of logic operations composed of AND, OR, XOR, complement, shift and addition. Bit-parallelism has been successfully applied to the longest common subsequence (LCS) and edit-distance problems, producing fast algorithms in practice. We have developed BitPAl, a bit-parallel algorithm for general, integer-scoring global alignment. Integer-scoring schemes assign integer weights for match, mismatch and insertion/deletion. The BitPAl method uses structural properties in the relationship between adjacent scores in the scoring matrix to construct classes of efficient algorithms, each designed for a particular set of weights. In timed tests, we show that BitPAl runs 7-25 times faster than a standard iterative algorithm. Source code is freely available for download at http://lobstah.bu.edu/BitPAl/BitPAl.html. BitPAl is implemented in C and runs on all major operating systems. jloving@bu.edu or yhernand@bu.edu or gbenson@bu.edu Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

  2. 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.

  3. 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.

  4. 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.

  5. Factorization of a 768-Bit RSA Modulus

    OpenAIRE

    Kleinjung, Thorsten; Aoki, Kazumaro; Franke, Jens; Lenstra, Arjen K.; Thome, Emmanuel; Bos, Joppe Willem; Gaudry, Pierrick; Kruppa, Alexander; Montgomery, Peter L.; Osvik, Dag Arne; Riele, Herman Te; Timofeev, Andrey; Zimmermann, Paul

    2010-01-01

    The original publication is available at www.springerlink.com; International audience; This paper reports on the factorization of the 768-bit number RSA-768 by the number field sieve factoring method and discusses some implications for RSA.

  6. Quantum bit commitment with misaligned reference frames

    International Nuclear Information System (INIS)

    Harrow, Aram; Oliveira, Roberto; Terhal, Barbara M.

    2006-01-01

    Suppose that Alice and Bob define their coordinate axes differently, and the change of reference frame between them is given by a probability distribution μ over SO(3). We show that this uncertainty of reference frame is of no use for bit commitment when μ is uniformly distributed over a (sub)group of SO(3), but other choices of μ can give rise to a partially or even arbitrarily secure bit commitment

  7. Artisanal fishing net float loss and a proposal for a float design solution

    Directory of Open Access Journals (Sweden)

    Paulo de Tarso Chaves

    2016-03-01

    Full Text Available Abstract Plastic floats from fishing nets are commonly found washed up on beaches in southern Brazil. They are usually broken and show signs of having been repaired. Characteristics of floats and interviews with fishermen suggest two main causes of float loss. First, collisions between active gear, bottom trawl nets for shrimp, and passive gear, drift nets for fish, destroy nets and release fragments of them, including floats. Second, the difficulty with which floats are inserted on the float rope of the nets when they are used near the surface. Floats are inserted to replace damaged or lost floats, or they may be removed if it is desired that the nets be used in deeper waters. Floats may thus be poorly fixed to the cables and lost. Here a new float design that offers greater safety in use and for the replacement of floats is described and tested.

  8. A short introduction to bit-string physics

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1997-06-01

    This paper starts with a personal memoir of how some significant ideas arose and events took place during the period from 1972, when the author first encountered Ted Bastin, to 1979, when the author proposed the foundation of ANPA. He then discusses 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 the historical material is a first pass at establishing new foundations for bit-string physics. An abstract model for a laboratory notebook and a historical record are developed, culminating in the bit-string representation. The author set up a tic-toc laboratory with two synchronized clocks and shows how this can be used to analyze arbitrary incoming data. This allows him 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 quantum gravity problem from his point of view and speculations about how a bit-string theory of strong, electromagnetic, weak and gravitational unification could take shape

  9. High bit depth infrared image compression via low bit depth codecs

    Science.gov (United States)

    Belyaev, Evgeny; Mantel, Claire; Forchhammer, Søren

    2017-08-01

    Future infrared remote sensing systems, such as monitoring of the Earth's environment by satellites, infrastructure inspection by unmanned airborne vehicles etc., will require 16 bit depth infrared images to be compressed and stored or transmitted for further analysis. Such systems are equipped with low power embedded platforms where image or video data is compressed by a hardware block called the video processing unit (VPU). However, in many cases using two 8-bit VPUs can provide advantages compared with using higher bit depth image compression directly. We propose to compress 16 bit depth images via 8 bit depth codecs in the following way. First, an input 16 bit depth image is mapped into 8 bit depth images, e.g., the first image contains only the most significant bytes (MSB image) and the second one contains only the least significant bytes (LSB image). Then each image is compressed by an image or video codec with 8 bits per pixel input format. We analyze how the compression parameters for both MSB and LSB images should be chosen to provide the maximum objective quality for a given compression ratio. Finally, we apply the proposed infrared image compression method utilizing JPEG and H.264/AVC codecs, which are usually available in efficient implementations, and compare their rate-distortion performance with JPEG2000, JPEG-XT and H.265/HEVC codecs supporting direct compression of infrared images in 16 bit depth format. A preliminary result shows that two 8 bit H.264/AVC codecs can achieve similar result as 16 bit HEVC codec.

  10. Design of the control system for fixed-point keeping in FPSO (Floating Production Storage and Offloading); FPSO no teiten hoji no tame no seigyokei no sekkei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kijima, K; Murata, W; Furukawa, Y [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1997-10-01

    The control system for keeping the fixed-point of ships against disturbance was designed by applying an ILQ (Inverse Linear Quadratic) control (possible to specify the response of controlled systems with time constant) theory, to study the effect of different time constants as design parameter on a fixed-point keeping performance. It was assumed that the controlled ship is equipped with two bow thrusters and one stern thruster of 30ton in output to generate a control force. For fixed-point keeping control, the state equation was derived to slave the controlled system to a target input. The ILQ design method uses the result of the inverse problem of optimum regulators. For designing control systems by using the ILQ control theory, the smallest time constant should be selected according to the most severe disturbance condition considering the response performance of controllers, to achieve fixed-point keeping of ships. In fixed-point keeping, it is also essential to put the initial position as close as possible to the target point. 2 refs., 6 figs., 2 tabs.

  11. Strength Tests on Hulls and Floats

    Science.gov (United States)

    Matthaes, K

    1942-01-01

    The present report deals with strength tests on hulls and floats intended in part for the collection of construction data for the design of these components and in part for the stress analysis of the finished hulls and floats.

  12. Stochastic p -Bits for Invertible Logic

    Science.gov (United States)

    Camsari, Kerem Yunus; Faria, Rafatul; Sutton, Brian M.; Datta, Supriyo

    2017-07-01

    Conventional semiconductor-based logic and nanomagnet-based memory devices are built out of stable, deterministic units such as standard metal-oxide semiconductor transistors, or nanomagnets with energy barriers in excess of ≈40 - 60 kT . In this paper, we show that unstable, stochastic units, which we call "p -bits," can be interconnected to create robust correlations that implement precise Boolean functions with impressive accuracy, comparable to standard digital circuits. At the same time, they are invertible, a unique property that is absent in standard digital circuits. When operated in the direct mode, the input is clamped, and the network provides the correct output. In the inverted mode, the output is clamped, and the network fluctuates among all possible inputs that are consistent with that output. First, we present a detailed implementation of an invertible gate to bring out the key role of a single three-terminal transistorlike building block to enable the construction of correlated p -bit networks. The results for this specific, CMOS-assisted nanomagnet-based hardware implementation agree well with those from a universal model for p -bits, showing that p -bits need not be magnet based: any three-terminal tunable random bit generator should be suitable. We present a general algorithm for designing a Boltzmann machine (BM) with a symmetric connection matrix [J ] (Ji j=Jj i) that implements a given truth table with p -bits. The [J ] matrices are relatively sparse with a few unique weights for convenient hardware implementation. We then show how BM full adders can be interconnected in a partially directed manner (Ji j≠Jj i) to implement large logic operations such as 32-bit binary addition. Hundreds of stochastic p -bits get precisely correlated such that the correct answer out of 233 (≈8 ×1 09) possibilities can be extracted by looking at the statistical mode or majority vote of a number of time samples. With perfect directivity (Jj i=0 ) a small

  13. A new assessment of floating exchange rates

    OpenAIRE

    Waimann, D. R.

    1981-01-01

    The switch to floating exchange rates during the 1970s has given economists the first comprehensive opportunity to assess the arguments for and against floating. Much new work has been done on various aspects of floating exchange rate behaviour. This article attempts a limited survey of the evidence concerning two important issues—whether floating exchange rates are inherently unstable and whether they harm international trade.

  14. 40 CFR 65.45 - External floating roof converted into an internal floating roof.

    Science.gov (United States)

    2010-07-01

    ... External floating roof converted into an internal floating roof. The owner or operator who elects to... 40 Protection of Environment 15 2010-07-01 2010-07-01 false External floating roof converted into an internal floating roof. 65.45 Section 65.45 Protection of Environment ENVIRONMENTAL PROTECTION...

  15. An efficient parallel pseudorandom bit generator based on an ...

    Indian Academy of Sciences (India)

    bit sequences pass all of the NIST SP800-22 statistical tests. ... local map, the chaotic behaviours of which depend only on the local map parameter, ..... 3, 4, ..., N. Thus, one-bit change of a 64-bit IV can result in 8(N − 2) + 1 bits change for 32N ...

  16. High bit depth infrared image compression via low bit depth codecs

    DEFF Research Database (Denmark)

    Belyaev, Evgeny; Mantel, Claire; Forchhammer, Søren

    .264/AVC codecs, which are usually available in efficient implementations, and compare their rate-distortion performance with JPEG2000, JPEG-XT and H.265/HEVC codecs supporting direct compression of infrared images in 16 bit depth format. A preliminary result shows that two 8 bit H.264/AVC codecs can...

  17. Bits extraction for palmprint template protection with Gabor magnitude and multi-bit quantization

    NARCIS (Netherlands)

    Mu, Meiru; Shao, X.; Ruan, Qiuqi; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

    2013-01-01

    In this paper, we propose a method of fixed-length binary string extraction (denoted by LogGM_DROBA) from low-resolution palmprint image for developing palmprint template protection technology. In order to extract reliable (stable and discriminative) bits, multi-bit equal-probability-interval

  18. Accurate Bit Error Rate Calculation for Asynchronous Chaos-Based DS-CDMA over Multipath Channel

    Science.gov (United States)

    Kaddoum, Georges; Roviras, Daniel; Chargé, Pascal; Fournier-Prunaret, Daniele

    2009-12-01

    An accurate approach to compute the bit error rate expression for multiuser chaosbased DS-CDMA system is presented in this paper. For more realistic communication system a slow fading multipath channel is considered. A simple RAKE receiver structure is considered. Based on the bit energy distribution, this approach compared to others computation methods existing in literature gives accurate results with low computation charge. Perfect estimation of the channel coefficients with the associated delays and chaos synchronization is assumed. The bit error rate is derived in terms of the bit energy distribution, the number of paths, the noise variance, and the number of users. Results are illustrated by theoretical calculations and numerical simulations which point out the accuracy of our approach.

  19. Have Floating Rates Been a Success?

    Science.gov (United States)

    Higham, David

    1983-01-01

    Floating exchange rates have not lived up to all expectations, but neither have they performed as badly as some critics have suggested. Examined are the impact of floating rates on balance of payments adjustment, domestic economic policy, and inflation and the claim that floating rates have displayed excessive fluctuations. (Author/RM)

  20. Floating Microparticulate Oral Diltiazem Hydrochloride Delivery ...

    African Journals Online (AJOL)

    Purpose: To formulate and evaluate floating microparticulate oral diltiazem delivery system for possible delivery to the heart. Method: Floating microspheres were prepared using cellulose acetate and Eudragit RS100 polymers by emulsion solvent evaporation technique. The dried floating microspheres were evaluated for ...

  1. Hydroelasticity of a Floating Plate

    DEFF Research Database (Denmark)

    Chen, X.; Jensen, Jørgen Juncher; Cui, W.

    2003-01-01

    The membrane forces are included in the hydroelastic analysis of a floating plate undergoing large vertical deflections in regular monochromatic multidirectional waves. The first-order vertical displacements induced by the linear wave exciting forces are calculated by the mode expansion method in...

  2. Ultra low bit-rate speech coding

    CERN Document Server

    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.

  3. Bit-padding information guided channel hopping

    KAUST Repository

    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.

  4. Pseudo-random bit generator based on lag time series

    Science.gov (United States)

    García-Martínez, M.; Campos-Cantón, E.

    2014-12-01

    In this paper, we present a pseudo-random bit generator (PRBG) based on two lag time series of the logistic map using positive and negative values in the bifurcation parameter. In order to hidden the map used to build the pseudo-random series we have used a delay in the generation of time series. These new series when they are mapped xn against xn+1 present a cloud of points unrelated to the logistic map. Finally, the pseudo-random sequences have been tested with the suite of NIST giving satisfactory results for use in stream ciphers.

  5. Introduction to bit slices and microprogramming

    International Nuclear Information System (INIS)

    Van Dam, A.

    1981-01-01

    Bit-slice logic blocks are fourth-generation LSI components which are natural extensions of traditional mulitplexers, registers, decoders, counters, ALUs, etc. Their functionality is controlled by microprogramming, typically to implement CPUs and peripheral controllers where both speed and easy programmability are required for flexibility, ease of implementation and debugging, etc. Processors built from bit-slice logic give the designer an alternative for approaching the programmibility of traditional fixed-instruction-set microprocessors with a speed closer to that of hardwired random logic. (orig.)

  6. Correct mutual information, quantum bit error rate and secure transmission efficiency in Wojcik's eavesdropping scheme on ping-pong protocol

    OpenAIRE

    Zhang, Zhanjun

    2004-01-01

    Comment: The wrong mutual information, quantum bit error rate and secure transmission efficiency in Wojcik's eavesdropping scheme [PRL90(03)157901]on ping-pong protocol have been pointed out and corrected

  7. Floating on the margins [Environmental issues for floating production platforms

    International Nuclear Information System (INIS)

    Grimshaw, R.

    1997-01-01

    The main environmental issues challenging oilfield development using floating production platforms in harsh environments such as the Atlantic frontier are discussed. These fall into two broad categories -operating conditions and biological disturbance. Particular combinations of wind and currents can lead to extremely difficult operating conditions through which floating units are expected to maintain production for economic reasons. This imposes stringent conditions on the design and construction of tanker hulls and of risers to enable them to remain connected at all times. Prediction of wind and wave forces is a crucial element of operational and safety planning. Fauna in seabed sediments disturbed by pipeline laying often relocate but some seeding back of colonies may be required in hard rock areas. Migration routes for cetaceans and the feeding grounds of marine birds must be considered and the potential long and short term damage to commercial fisheries through discharges need to be assessed. A significant risk is the interaction of sub-sea facilities and fishing gear and oil spills. Operational and accidental discharges of production chemicals, produced water containing oil, deck drainage and treated sewage, and discharges to air from flaring and utility exhausts are of major environmental concern calling for mitigation and protection measures and contingency plans. Some of the environmental issues associated with decommissioning are reduced by the use of floating platforms but there are global and national regulations governing the process. (UK)

  8. Entropy of a bit-shift channel

    NARCIS (Netherlands)

    Baggen, Stan; Balakirsky, Vladimir; Denteneer, Dee; Egner, Sebastian; Hollmann, Henk; Tolhuizen, Ludo; Verbitskiy, Evgeny

    2006-01-01

    We consider a simple transformation (coding) of an iid source called a bit-shift channel. This simple transformation occurs naturally in magnetic or optical data storage. The resulting process is not Markov of any order. We discuss methods of computing the entropy of the transformed process, and

  9. 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...

  10. A theory of managed floating

    OpenAIRE

    Wollmershäuser, Timo

    2004-01-01

    After the experience with the currency crises of the 1990s, a broad consensus has emerged among economists that such shocks can only be avoided if countries that decided to maintain unrestricted capital mobility adopt either independently floating exchange rates or very hard pegs (currency boards, dollarisation). As a consequence of this view which has been enshrined in the so-called impossible trinity all intermediate currency regimes are regarded as inherently unstable. As far as the econom...

  11. Hywind floating wind turbine project

    Energy Technology Data Exchange (ETDEWEB)

    Crome, Tim

    2010-07-01

    The Hywind floating wind turbine concept was developed by StatoilHydro. Technip was awarded the contract for engineering, fabrication and installation of a demonstration unit in May 2008 and the completed wind turbine was installed mid June 2009 at the west coast of Norway on 220 m water depth. The demonstration unit will generate 2,3 MW and is equipped with instrumentation for monitoring mooring forces, strains and motions. The fabrication of the SPAR type steel substructure was performed at Technip Offshore Finland facilities in Pori and was towed horizontally from Finland to Norway, where it was upended to a vertical position by water filling. The completed floating wind turbine was towed vertically to the final location west of Karmoey and connected to the pre-installed three legged anchor system using an Anchor Handling Tug type vessel. The wind turbine test period is scheduled to start in September 2009. Statoil will monitor the performance of the system for two years before decision will be taken for further development. The paper will present the main challenges and lessons learned through design, fabrication and installation of this first of its kind structure. Main emphasis will be on the special challenges experienced for this floating, catenary moored, slender unit which is highly exposed for wind induced forces in addition to current and waves in hostile North Sea environments. (Author)

  12. Can flexibility help you float?

    Science.gov (United States)

    Burton, L. J.; Bush, J. W. M.

    2012-10-01

    We consider the role of flexibility in the weight-bearing characteristics of bodies floating at an interface. Specifically, we develop a theoretical model for a two-dimensional thin floating plate that yields the maximum stable plate load and optimal stiffness for weight support. Plates small relative to the capillary length are primarily supported by surface tension, and their weight-bearing potential does not benefit from flexibility. Above a critical size comparable to the capillary length, flexibility assists interfacial flotation. For plates on the order of and larger than the capillary length, deflection from an initially flat shape increases the force resulting from hydrostatic pressure, allowing the plate to support a greater load. In this large plate limit, the shape that bears the most weight is a semicircle, which displaces the most fluid above the plate for a fixed plate length. Exact results for maximum weight-bearing plate shapes are compared to analytic approximations made in the limits of large and small plate sizes. The value of flexibility for floating to a number of biological organisms is discussed in light of our study.

  13. Characterization of airborne float coal dust emitted during continuous mining, longwall mining and belt transport.

    Science.gov (United States)

    Shahan, M R; Seaman, C E; Beck, T W; Colinet, J F; Mischler, S E

    2017-09-01

    Float coal dust is produced by various mining methods, carried by ventilating air and deposited on the floor, roof and ribs of mine airways. If deposited, float dust is re-entrained during a methane explosion. Without sufficient inert rock dust quantities, this float coal dust can propagate an explosion throughout mining entries. Consequently, controlling float coal dust is of critical interest to mining operations. Rock dusting, which is the adding of inert material to airway surfaces, is the main control technique currently used by the coal mining industry to reduce the float coal dust explosion hazard. To assist the industry in reducing this hazard, the Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health initiated a project to investigate methods and technologies to reduce float coal dust in underground coal mines through prevention, capture and suppression prior to deposition. Field characterization studies were performed to determine quantitatively the sources, types and amounts of dust produced during various coal mining processes. The operations chosen for study were a continuous miner section, a longwall section and a coal-handling facility. For each of these operations, the primary dust sources were confirmed to be the continuous mining machine, longwall shearer and conveyor belt transfer points, respectively. Respirable and total airborne float dust samples were collected and analyzed for each operation, and the ratio of total airborne float coal dust to respirable dust was calculated. During the continuous mining process, the ratio of total airborne float coal dust to respirable dust ranged from 10.3 to 13.8. The ratios measured on the longwall face were between 18.5 and 21.5. The total airborne float coal dust to respirable dust ratio observed during belt transport ranged between 7.5 and 21.8.

  14. Surface and Internal Waves due to a Moving Load on a Very Large Floating Structure

    Directory of Open Access Journals (Sweden)

    Taro Kakinuma

    2012-01-01

    Full Text Available Interaction of surface/internal water waves with a floating platform is discussed with nonlinearity of fluid motion and flexibility of oscillating structure. The set of governing equations based on a variational principle is applied to a one- or two-layer fluid interacting with a horizontally very large and elastic thin plate floating on the water surface. Calculation results of surface displacements are compared with the existing experimental data, where a tsunami, in terms of a solitary wave, propagates across one-layer water with a floating thin plate. We also simulate surface and internal waves due to a point load, such as an airplane, moving on a very large floating structure in shallow water. The wave height of the surface or internal mode is amplified when the velocity of moving point load is equal to the surface- or internal-mode celerity, respectively.

  15. Supersymmetric quantum mechanics for string-bits

    International Nuclear Information System (INIS)

    Thorn, C.B.

    1997-01-01

    The authors develop possible versions of supersymmetric single particle quantum mechanics, with application to superstring-bit models in view. The authors focus principally on space dimensions d = 1,2,4,8, the transverse dimensionalities of superstring in 3, 4, 7, 10 space-time dimensions. These are the cases for which classical superstring makes sense, and also the values of d for which Hooke's force law is compatible with the simplest superparticle dynamics. The basic question they address is: when is it possible to replace such harmonic force laws with more general ones, including forces which vanish at large distances? This is an important question because forces between string-bits that do not fall off with distance will almost certainly destroy cluster decomposition. They show that the answer is affirmative for d = 1,2, negative for d = 8, and so far inconclusive for d = 4

  16. Single Bit Radar Systems for Digital Integration

    OpenAIRE

    Bjørndal, Øystein

    2017-01-01

    Small, low cost, radar systems have exciting applications in monitoring and imaging for the industrial, healthcare and Internet of Things (IoT) sectors. We here explore, and show the feasibility of, several single bit square wave radar architectures; that benefits from the continuous improvement in digital technologies for system-on-chip digital integration. By analysis, simulation and measurements we explore novel and harmonic-rich continuous wave (CW), stepped-frequency CW (SFCW) and freque...

  17. 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.

  18. Development of an RSFQ 4-bit ALU

    International Nuclear Information System (INIS)

    Kim, J. Y.; Baek, S. H.; Kim, S. H.; Kang, K. R.; Jung, K. R.; Lim, H. Y.; Park, J. H.; Han, T. S.

    2005-01-01

    We have developed and tested an RSFQ 4-bit Arithmetic Logic Unit (ALU) based on half adder cells and de switches. ALU is a core element of a computer processor that performs arithmetic and logic operations on the operands in computer instruction words. The designed ALU had limited operation functions of OR, AND, XOR, and ADD. It had a pipeline structure. We have simulated the circuit by using Josephson circuit simulation tools in order to reduce the timing problem, and confirmed the correct operation of the designed ALU. We used simulation tools of XIC TM ,WRspice TM , and Julia. The fabricated 4-bit ALU circuit had a size of 3000 calum X 1500, and the chip size was 5 mm X 5 mm. The test speeds were 1000 kHz and 5 GHz. For high-speed test, we used an eye-diagram technique. Our 4-bit ALU operated correctly up to 5 GHz clock frequency. The chip was tested at the liquid-helium temperature.

  19. 14 CFR 27.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 27.753 Section 27.753... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 27.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

  20. 14 CFR 29.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 29.753 Section 29.753... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.753 Main float design. (a) Bag floats. Each bag float must be designed to withstand— (1) The maximum pressure differential...

  1. Drilling bits for deep drilling and process for their manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Rhode, H.; Juergens, R.; Feenstra, R.; Busking, B.E.

    1978-11-30

    The invention concerns a drilling head or a drilling bit for use in deep drilling in underground formations and particularly concerns a drilling bit with a drilling bit body, which has a shank and a hollow space, which is connected with a duct extending through the shank. The drilling bit body has several separate cutting elements for removing material from the floor of a borehole and hydraulic devices for cooling and/or cleaning the cutting elements are provided.

  2. Lathe tool bit and holder for machining fiberglass materials

    Science.gov (United States)

    Winn, L. E. (Inventor)

    1972-01-01

    A lathe tool and holder combination for machining resin impregnated fiberglass cloth laminates is described. The tool holder and tool bit combination is designed to accommodate a conventional carbide-tipped, round shank router bit as the cutting medium, and provides an infinite number of cutting angles in order to produce a true and smooth surface in the fiberglass material workpiece with every pass of the tool bit. The technique utilizes damaged router bits which ordinarily would be discarded.

  3. Method to manufacture bit patterned magnetic recording media

    Science.gov (United States)

    Raeymaekers, Bart; Sinha, Dipen N

    2014-05-13

    A method to increase the storage density on magnetic recording media by physically separating the individual bits from each other with a non-magnetic medium (so-called bit patterned media). This allows the bits to be closely packed together without creating magnetic "cross-talk" between adjacent bits. In one embodiment, ferromagnetic particles are submerged in a resin solution, contained in a reservoir. The bottom of the reservoir is made of piezoelectric material.

  4. Floating Microparticulate Oral Diltiazem Hydrochloride Delivery ...

    African Journals Online (AJOL)

    Delivery System for Improved Delivery to Heart ... Conclusion: Microparticulate floating (gastroretentive) oral drug delivery system of diltiazem prepared ..... treatment of cardiac disease. ... hydrochloride-loaded mucoadhesive microspheres.

  5. Bit selection using field drilling data and mathematical investigation

    Science.gov (United States)

    Momeni, M. S.; Ridha, S.; Hosseini, S. J.; Meyghani, B.; Emamian, S. S.

    2018-03-01

    A drilling process will not be complete without the usage of a drill bit. Therefore, bit selection is considered to be an important task in drilling optimization process. To select a bit is considered as an important issue in planning and designing a well. This is simply because the cost of drilling bit in total cost is quite high. Thus, to perform this task, aback propagation ANN Model is developed. This is done by training the model using several wells and it is done by the usage of drilling bit records from offset wells. In this project, two models are developed by the usage of the ANN. One is to find predicted IADC bit code and one is to find Predicted ROP. Stage 1 was to find the IADC bit code by using all the given filed data. The output is the Targeted IADC bit code. Stage 2 was to find the Predicted ROP values using the gained IADC bit code in Stage 1. Next is Stage 3 where the Predicted ROP value is used back again in the data set to gain Predicted IADC bit code value. The output is the Predicted IADC bit code. Thus, at the end, there are two models that give the Predicted ROP values and Predicted IADC bit code values.

  6. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  7. Nuclear floating power desalination complexes

    International Nuclear Information System (INIS)

    Panov, Y.K.; Polunichev, V.I.; Zverev, K.V.

    1998-01-01

    Russia is a single country in the world which possesses a powerful ice-breaker transport fleet that allows a solution of important social-economic tasks of the country's northern regions by maintaining a year-round navigation along the Arctic sea route. A total operating record of the marine nuclear reactors up until till now exceeds 150 reactor-years, with their main equipment operating life reacting 120 thousand hours. Design and constructional progresses have been made continuously during forty years of nuclear-powered ships construction in Russia. Well proven technology of all components experienced in the marine nuclear reactors give grounds to recommend marine NSSSs of KLT-40 type as energy sources for the heat and power co-generation plants and the sea water desalination complexes, particularly as a floating installation. Co-generation stations are considered for deployment in the extreme Northern Region of Russia. Nuclear floating desalination complexes can be used for drinkable water production in the coastal regions of Northern Africa, the Near East, India etc. (author)

  8. A Bit Stream Scalable Speech/Audio Coder Combining Enhanced Regular Pulse Excitation and Parametric Coding

    Science.gov (United States)

    Riera-Palou, Felip; den Brinker, Albertus C.

    2007-12-01

    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).

  9. A Bit Stream Scalable Speech/Audio Coder Combining Enhanced Regular Pulse Excitation and Parametric Coding

    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.

  10. Vertical pump with free floating check valve

    International Nuclear Information System (INIS)

    Lindsay, M.

    1980-01-01

    A vertical pump is described which has a bottom discharge with a free floating check valve disposed in the outlet plenum thereof. The free floating check valve comprises a spherical member with a hemispherical cage-like member attached thereto which is capable of allowing forward or reverse flow under appropriate conditions while preventing reverse flow under inappropriate conditions

  11. Image processing on the image with pixel noise bits removed

    Science.gov (United States)

    Chuang, Keh-Shih; Wu, Christine

    1992-06-01

    Our previous studies used statistical methods to assess the noise level in digital images of various radiological modalities. We separated the pixel data into signal bits and noise bits and demonstrated visually that the removal of the noise bits does not affect the image quality. In this paper we apply image enhancement techniques on noise-bits-removed images and demonstrate that the removal of noise bits has no effect on the image property. The image processing techniques used are gray-level look up table transformation, Sobel edge detector, and 3-D surface display. Preliminary results show no noticeable difference between original image and noise bits removed image using look up table operation and Sobel edge enhancement. There is a slight enhancement of the slicing artifact in the 3-D surface display of the noise bits removed image.

  12. What is the size of a floating sheath? An answer

    Science.gov (United States)

    Voigt, Farina; Naggary, Schabnam; Brinkmann, Ralf Peter

    2016-09-01

    The formation of a non-neutral boundary sheath in front of material surfaces is universal plasma phenomenon. Despite several decades of research, however, not all related issues are fully clarified. In a recent paper, Chabert pointed out that this lack of clarity applies even to the seemingly innocuous question ``What the size of a floating sheath?'' This contribution attempts to provide an answer that is not arbitrary: The size of a floating sheath is defined as the plate separation of an equivalent parallel plate capacitor. The consequences of the definition are explored with the help of a self-consistent sheath model, and a comparison is made with other sheath size definitions. Deutsche Forschungsgemeinschaft within SFB TR 87.

  13. A 16 bit camac ADC with memory

    International Nuclear Information System (INIS)

    Wikne, J.C.

    1986-01-01

    A 16 bit camac-programmable analog-to-digital converter (ADC) with incorporated memory and sampling clock is described. This single-width camac module is especially suited for autonomous, multi-sample data acquisition with high precision. The ADC itself is a hybrid, the ADC76 from Burr-Brown, featuring a programmable input range and direct parallel output in two's complement form. The input programming is done by means of dual-in-line switches, giving input spans from 1.25 V to 20 V, unipolar or bipolar. The outline of the programming of the ADC input and the calibration of the unit is given

  14. Measurement accuracy, bit-strings, Manthey's quaternions, and RRQM

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1995-01-01

    The author continues the discussion started last year. By now three potentially divergent research programs have surfaced in ANPA: (1) the Bastin-Kilmister understanding of the combinatorial hierarchy (Clive's open-quotes Menshevikclose quotes position); (2) the author's bit-string open-quotes Theory of Everythingclose quotes (which Clive has dubbed open-quotes Bolshevikclose quotes); (3) Manthey's cycle hierarchy based on co-occurrence and mutual exclusion that Clive helped him map onto quaternions (as an yet unnamed heresy?). Unless a common objective can be found, these three points of view will continue to diverge. The authors suggests the reconstruction of relativistic quantum mechanism (RRQM) as a reasonable, and attainable, goal that might aid convergence rather than divergence

  15. Investigation of PDC bit failure base on stick-slip vibration analysis of drilling string system plus drill bit

    Science.gov (United States)

    Huang, Zhiqiang; Xie, Dou; Xie, Bing; Zhang, Wenlin; Zhang, Fuxiao; He, Lei

    2018-03-01

    The undesired stick-slip vibration is the main source of PDC bit failure, such as tooth fracture and tooth loss. So, the study of PDC bit failure base on stick-slip vibration analysis is crucial to prolonging the service life of PDC bit and improving ROP (rate of penetration). For this purpose, a piecewise-smooth torsional model with 4-DOF (degree of freedom) of drilling string system plus PDC bit is proposed to simulate non-impact drilling. In this model, both the friction and cutting behaviors of PDC bit are innovatively introduced. The results reveal that PDC bit is easier to fail than other drilling tools due to the severer stick-slip vibration. Moreover, reducing WOB (weight on bit) and improving driving torque can effectively mitigate the stick-slip vibration of PDC bit. Therefore, PDC bit failure can be alleviated by optimizing drilling parameters. In addition, a new 4-DOF torsional model is established to simulate torsional impact drilling and the effect of torsional impact on PDC bit's stick-slip vibration is analyzed by use of an engineering example. It can be concluded that torsional impact can mitigate stick-slip vibration, prolonging the service life of PDC bit and improving drilling efficiency, which is consistent with the field experiment results.

  16. Supersymmetric quantum mechanics for string bits

    International Nuclear Information System (INIS)

    Thorn, C.B.

    1997-01-01

    We develop possible versions of supersymmetric single-particle quantum mechanics, with application to superstring-bit models in view. We focus principally on space dimensions d=1,2,4,8, the transverse dimensionalities of superstring in 3, 4, 6, and 10 space-time dimensions. These are the cases for which open-quotes classicalclose quotes superstring makes sense, and also the values of d for which Hooke close-quote s force law is compatible with the simplest superparticle dynamics. The basic question we address is the following: When is it possible to replace such harmonic force laws with more general ones, including forces which vanish at large distances? This is an important question because forces between string bits that do not fall off with distance will almost certainly destroy cluster decomposition. We show that the answer is affirmative for d=1,2, negative for d=8, and so far inconclusive for d=4. copyright 1997 The American Physical Society

  17. Growing halophytes floating at sea

    Directory of Open Access Journals (Sweden)

    Ricardo Radulovich

    2017-11-01

    Full Text Available Freshwater shortages are increasingly limiting both irrigated and rainfed agriculture. To expand possibilities for controlled plant production without using land nor freshwater, we cultivated potted halophytes floating at sea that were provided with rain- and seawater. Plantlets of two mangroves (Avicennia germinans and Rhizophora mangle and plants of two herbaceous species, sea purslane (Sesuvium portulacastrum and salt couch grass (Sporobolus virginicus were grown in near-coastal tropical Pacific waters of Costa Rica for 733 days. There were a total of 504 rainless days, including two dry periods of ca. 150 d long each, evidencing prolonged and exclusive reliance on seawater. Pots with a sandy soil mixture and the transplanted plants were placed on low-cost wooden floating rafts with their lower end perforated and immersed for capillary rise of water. Free seawater entry and exit through the bottom from bobbing with waves, which also occasionally added water from the top, effectively controlled soil salinity build-up even during the rainless seasons. Continuous leaching made necessary frequent fertilizer addition. No water deficit symptoms were observed and midday canopy temperature during rainless periods was not significantly different between species or from air temperature. With all-year-round growth, height increase of mangrove plantlets ranged from 208.1 to 401.5 mm yr−1. Fresh biomass production of sea purslane and the grass was 10.9 and 3.0 kg m−2 yr−1 respectively. High yield, edibility and protein content of 10.2% dry weight established sea purslane as a potential crop. While further research is needed, the method evidenced to be a viable plant production option of potentially far-reaching applications.

  18. Comparison of 12-bit and 8-bit gray scale resolution in MR imaging of the CNS

    International Nuclear Information System (INIS)

    Smith, H.J.; Bakke, S.J.; Smevik, B.; Hald, J.K.; Moen, G.; Rudenhed, B.; Abildgaard, A.

    1992-01-01

    A reduction in gray scale resolution of digital images from 12 to 8 bits per pixel usually means halving the storage space needed for the images. Theoretically, important diagnostic information may be lost in the process. We compared the sensitivity and specificity achieved by 4 radiologists in reading laser-printed films of original 12-bit MR images and cathode ray tube displays of the same images which had been compressed to 8 bits per pixel using a specially developed computer program. Receiver operating characteristics (ROC) curves showed no significant differences between film reading and screen reading. A paired 2-tailed t-test, applied on the data for actually positive cases, showed that the combined, average performance of the reviewers was significantly better at screen reading than at film reading. No such differences were found for actually negative cases. Some individual differences were found, but it is concluded that gray scale resolution of MR images may be reduced from 12 to 8 bits per pixel without any significant reduction in diagnostic information. (orig.)

  19. Towards Interactive Steering of a Very Large Floating Structure Code by Using HPC Parallelisation Strategies

    KAUST Repository

    Frisch, Jerome; Gao, Ruiping; Mundani, Ralf-Peter; Wang, Chien Ming; Rank, Ernst

    2012-01-01

    Very large floating structures (VLFSs) have been used for broad applications such as floating storage facilities, floating piers, floating bridges, floating airports, entertainment facilities, even habitation, and other purposes. Owing to its small

  20. A digital divider with extension bits for position-sensitive detectors

    International Nuclear Information System (INIS)

    Koike, Masaki; Hasegawa, Ken-ichi

    1988-01-01

    Digitizing errors produced in a digital divider for position-sensitive detectors have been reduced by adding extension bits to data bits. A relation between the extension bits and the data bits to obtain perfect position uniformity is also given. A digital divider employing 10 bit ADCs and 6 bit extension circuits has been constructed. (orig.)

  1. 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...

  2. 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...... 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...... 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, such as for bit safety, accessibility...

  3. Bit-commitment-based quantum coin flipping

    International Nuclear Information System (INIS)

    Nayak, Ashwin; Shor, Peter

    2003-01-01

    In this paper we focus on a special framework for quantum coin-flipping protocols, bit-commitment-based protocols, within which almost all known protocols fit. We show a lower bound of 1/16 for the bias in any such protocol. We also analyze a sequence of multiround protocols that tries to overcome the drawbacks of the previously proposed protocols in order to lower the bias. We show an intricate cheating strategy for this sequence, which leads to a bias of 1/4. This indicates that a bias of 1/4 might be optimal in such protocols, and also demonstrates that a more clever proof technique may be required to show this optimality

  4. Second quantization in bit-string physics

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1992-08-01

    Using a new fundamental theory based on bit-strings we derived a finite and discrete version of the solutions of the free one particle Dirac equation as segmented trajectories with steps of length h/mc along the forward and backward light cones executed at velocity ±c. Interpreting the statistical fluctuations which cause the bends in these segmented trajectories as emission and absorption of radiation, these solutions are analagous to a fermion propagator in a second quantized theory. This allows us to interpret the mass parameter in the step length as the physical mass of the free particle. The radiation in interaction with it has the usual harmonic oscillator structure of a second quantized theory. We sketch on these free particle masses can be generated gravitationally using the combinatorial hierarchy sequence (3,10,137,2 127 +136), and some of the predictive consequences

  5. Balance, Sustainable Development, and Integration: Innovative Path for BIT Practice

    OpenAIRE

    Zeng Huaqun

    2014-01-01

    Bilateral investment treaties (BITs) have emerged as one of the most remarkable recent developments in international law and the hot topic of international lawyers. The author indicates that in the history of BIT practice, there is an issue on imbalance and/or un-equality between developed states and developing states due to historical and practical reasons. Under the economic globalization the main clauses of BITs have been further developed to the traditional track elaborately designed by d...

  6. 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.

  7. 14 CFR 23.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 23.753 Section 23.753... STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Floats and Hulls § 23.753 Main float design. Each seaplane main float must meet the requirements of § 23.521. [Doc...

  8. 14 CFR 29.757 - Hull and auxiliary float strength.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and auxiliary float strength. 29.757... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction Floats and Hulls § 29.757 Hull and auxiliary float strength. The hull, and auxiliary floats if used, must withstand the...

  9. Quantum bit commitment with cheat sensitive binding and approximate sealing

    Science.gov (United States)

    Li, Yan-Bing; Xu, Sheng-Wei; Huang, Wei; Wan, Zong-Jie

    2015-04-01

    This paper proposes a cheat-sensitive quantum bit commitment scheme based on single photons, in which Alice commits a bit to Bob. Here, Bob’s probability of success at cheating as obtains the committed bit before the opening phase becomes close to \\frac{1}{2} (just like performing a guess) as the number of single photons used is increased. And if Alice alters her committed bit after the commitment phase, her cheating will be detected with a probability that becomes close to 1 as the number of single photons used is increased. The scheme is easy to realize with present day technology.

  10. Improved Bit Rate Control for Real-Time MPEG Watermarking

    Directory of Open Access Journals (Sweden)

    Pranata Sugiri

    2004-01-01

    Full Text Available The alteration of compressed video bitstream due to embedding of digital watermark tends to produce unpredictable video bit rate variations which may in turn lead to video playback buffer overflow/underflow or transmission bandwidth violation problems. This paper presents a novel bit rate control technique for real-time MPEG watermarking applications. In our experiments, spread spectrum watermarks are embedded in the quantized DCT domain without requantization and motion reestimation to achieve fast watermarking. The proposed bit rate control scheme evaluates the combined bit lengths of a set of multiple watermarked VLC codewords, and successively replaces watermarked VLC codewords having the largest increase in bit length with their corresponding unmarked VLC codewords until a target bit length is achieved. The proposed method offers flexibility and scalability, which are neglected by similar works reported in the literature. Experimental results show that the proposed bit rate control scheme is effective in meeting the bit rate targets and capable of improving the watermark detection robustness for different video contents compressed at different bit rates.

  11. FPGA implementation of bit controller in double-tick architecture

    Science.gov (United States)

    Kobylecki, Michał; Kania, Dariusz

    2017-11-01

    This paper presents a comparison of the two original architectures of programmable bit controllers built on FPGAs. Programmable Logic Controllers (which include, among other things programmable bit controllers) built on FPGAs provide a efficient alternative to the controllers based on microprocessors which are expensive and often too slow. The presented and compared methods allow for the efficient implementation of any bit control algorithm written in Ladder Diagram language into the programmable logic system in accordance with IEC61131-3. In both cases, we have compared the effect of the applied architecture on the performance of executing the same bit control program in relation to its own size.

  12. Genetics Home Reference: Floating-Harbor syndrome

    Science.gov (United States)

    ... Patton MA, Hurst J, Donnai D, McKeown CM, Cole T, Goodship J. Floating-Harbor syndrome. J Med ... medicine? What is newborn screening? New Pages Lyme disease Fibromyalgia White-Sutton syndrome All New & Updated Pages ...

  13. Cholecystosonographic findings of clonorchiasis: Floating echogenic foci

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ho Kyun [Choong Joo X-ray Clinic, Choongjoo (Korea, Republic of)

    1989-06-15

    Author analysed cholecystosonographic findings in 22 patients with clonorchiasis, suspected prospectively by ultrasound and proved subsequently by demonstration of eggs in the stools. Fifteen gallbladders had nonshadowing, fusiform, discrete echogenic foci measuring 3{approx}6 mm in the lumen. Among these, the echogenic foci floated spontaneously in three cases, while in twelve cases they floated by position change or a light blow by the transducer. In the rest of the seven gallbladders, the echogenic foci were at the dependent portion. In the in vitro study with a worm suspension in saline in a surgical glove, the same echogenic foci as those seen in the gallbladders were demonstrated. The echogenic foci were precipitated in the dependent portion but float with a light blow on the glove. Author conclude that the floating echogenic foci in the lumen of the gallbladder are due to adult worms of clonorchis sinensis.

  14. Cholecystosonographic findings of clonorchiasis: Floating echogenic foci

    International Nuclear Information System (INIS)

    Kim, Ho Kyun

    1989-01-01

    Author analysed cholecystosonographic findings in 22 patients with clonorchiasis, suspected prospectively by ultrasound and proved subsequently by demonstration of eggs in the stools. Fifteen gallbladders had nonshadowing, fusiform, discrete echogenic foci measuring 3∼6 mm in the lumen. Among these, the echogenic foci floated spontaneously in three cases, while in twelve cases they floated by position change or a light blow by the transducer. In the rest of the seven gallbladders, the echogenic foci were at the dependent portion. In the in vitro study with a worm suspension in saline in a surgical glove, the same echogenic foci as those seen in the gallbladders were demonstrated. The echogenic foci were precipitated in the dependent portion but float with a light blow on the glove. Author conclude that the floating echogenic foci in the lumen of the gallbladder are due to adult worms of clonorchis sinensis

  15. Design and preparation of controlled floating gastroretentive ...

    African Journals Online (AJOL)

    gastroretentive delivery systems for enhanced fexofenadine ... Abstract. Purpose: To design and prepare effervescent floating gastroretentive tablets for controlled fexofenadine ..... Complex of Carbopol with Polyvinylpyrrolidone as a. Matrix for ...

  16. Dynamic Response of a Floating Bridge Structure

    OpenAIRE

    Viuff, Thomas; Leira, Bernt Johan; Øiseth, Ole; Xiang, Xu

    2016-01-01

    A theoretical overview of the stochastic dynamic analysis of a floating bridge structure is presented. Emphasis is on the wave-induced response and the waves on the sea surface are idealized as a zero mean stationary Gaussian process. The first-order wave load processes are derived using linear potential theory and the structural idealization is based on the Finite Element Method. A frequency response calculation is presented for a simplified floating bridge structure example emphasising the ...

  17. Fear of Floating: Exchange Rate Flexibility Indices

    OpenAIRE

    Reinhart, Carmen

    2001-01-01

    Many emerging market countries have suffered financial crises. One view blames soft pegs for these crises. Adherents to that view suggest that countries move to corner solutions--hard pegs or floating exchange rates. We analyze the behavior of exchange rates, reserves, and interest rates to assess whether there is evidence that country practice is moving toward corner solutions. We focus on whether countries that claim they are floating are indeed doing so. We find that countries that say th...

  18. Sensitivity analysis of floating offshore wind farms

    International Nuclear Information System (INIS)

    Castro-Santos, Laura; Diaz-Casas, Vicente

    2015-01-01

    Highlights: • Develop a sensitivity analysis of a floating offshore wind farm. • Influence on the life-cycle costs involved in a floating offshore wind farm. • Influence on IRR, NPV, pay-back period, LCOE and cost of power. • Important variables: distance, wind resource, electric tariff, etc. • It helps to investors to take decisions in the future. - Abstract: The future of offshore wind energy will be in deep waters. In this context, the main objective of the present paper is to develop a sensitivity analysis of a floating offshore wind farm. It will show how much the output variables can vary when the input variables are changing. For this purpose two different scenarios will be taken into account: the life-cycle costs involved in a floating offshore wind farm (cost of conception and definition, cost of design and development, cost of manufacturing, cost of installation, cost of exploitation and cost of dismantling) and the most important economic indexes in terms of economic feasibility of a floating offshore wind farm (internal rate of return, net present value, discounted pay-back period, levelized cost of energy and cost of power). Results indicate that the most important variables in economic terms are the number of wind turbines and the distance from farm to shore in the costs’ scenario, and the wind scale parameter and the electric tariff for the economic indexes. This study will help investors to take into account these variables in the development of floating offshore wind farms in the future

  19. Behavioral and psychosocial interventions for HIV prevention in floating populations in China over the past decade: A systematic literature review and meta-analysis

    NARCIS (Netherlands)

    X. Liu (Xiaona); V. Erasmus (Vicky); Q. Wu (Qing); J.H. Richardus (Jan Hendrik)

    2014-01-01

    textabstractBackground: Floating populations have been repeatedly characterized as "the tipping point" for the HIV epidemic in China. This study aims to systematically summarize and assess the effectiveness of HIV prevention interventions in floating populations in China over the past decade.

  20. Multiple Memory Structure Bit Reversal Algorithm Based on Recursive Patterns of Bit Reversal Permutation

    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.

  1. EVALUATION OF PROPERTIES OF BIT VALUATION OF ...

    African Journals Online (AJOL)

    User

    industry because of the additional elasticity imparted to the binder and ... steel ball. Figure 2 shows the softening point of tyres modified bitumen. Softening points values .... Malaysia University Transpiration Research. Forum and Conferences ...

  2. Bit-Wise Arithmetic Coding For Compression Of Data

    Science.gov (United States)

    Kiely, Aaron

    1996-01-01

    Bit-wise arithmetic coding is data-compression scheme intended especially for use with uniformly quantized data from source with Gaussian, Laplacian, or similar probability distribution function. Code words of fixed length, and bits treated as being independent. Scheme serves as means of progressive transmission or of overcoming buffer-overflow or rate constraint limitations sometimes arising when data compression used.

  3. Report on ignitability testing of ''no-flow'' push bit

    International Nuclear Information System (INIS)

    Witwer, K.S.

    1997-01-01

    Testing was done to determine if an ignition occurs during a sixty foot drop of a Universal Sampler onto a push-mode bit in a flammable gas environment. Ten drops each of the sampler using both a push-mode and rotary mode insert onto a push-mode bit were completed. No ignition occurred during any of the drops

  4. Circuit and interconnect design for high bit-rate applications

    NARCIS (Netherlands)

    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

  5. The bit's the thing : PDC bits are the sparkly new best friend of drillers everywhere

    Energy Technology Data Exchange (ETDEWEB)

    Cook, D.

    2008-09-15

    Polycrystalline diamond compact (PDC) cutters were introduced to the oil and gas industry in 1972. The drill bit technology has made significant advances since its introduction, and the PDC bits are now more widely used than conventional roller cone bits. This article discussed new PDC drill bits designed to have rates of penetration (ROP) of over 1000 feet an hour, run distances of up to 22,000 feet, and have cumulative depths of 180,000 feet. A diamond volume management (DVM) system is used to place the diamond where it is needed for specific applications. Designed by Precise Drilling Component Ltd, the bits are accompanied by thermo stable cutters developed to increase the stability of the PDC bits. Precise Drilling Component is now supplying the drilling equipment to major international oil companies. The company has also developed new abrasion-resistant cutters and improved hydraulics that have increased durability and stability, as well as lower drilling costs. The PDC cutters are able to remove rock more efficiently than the grinding and gouging actions of roller bits, which translates into faster penetration rates and longer bit lives. PDC bits are increasingly being used in steam assisted gravity drainage (SAGD) operations as the tungsten carbide matrix used for the PDC bits is able to withstand the abrasive sands encountered in oil sands wellbores. It was concluded that the PDC drill bits will continue to be optimized for use in harsh oil sands conditions. New optimization features and analytical models for improving drilling efficiency were also outlined. 4 figs.

  6. Uniqueness: skews bit occurrence frequencies in randomly generated fingerprint libraries.

    Science.gov (United States)

    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.

  7. Individual Drilling Bit Design and Optimization in Mahu Area

    Directory of Open Access Journals (Sweden)

    Zhang Wenbo

    2017-01-01

    Full Text Available There are three sets of gravels in Mahu region. The gravels formation is characterized by high heterogeneity, high abrasiveness and poor drillability. It is so difficult to optimize bit that restrict seriously the overall exploration and development process. The compressive strength, internal friction angle, and drillability of the formation are tested to check the rock mechanical characteristic profile established by logging data. The individual bit design is carried out by the 3D simulation technology. A new PDC bit type is designed to form the drill bit series for Mahu area. Single PDC bit increases 90% of the drilling footage. The trip average footage is improved 3.45 times, the horizontal section average penetration increased 34.8%. The technical achievements have greatly improved economic development benefits of Mahu region by improving drilling speed and saving drilling costs.

  8. 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.

  9. 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.

  10. Use break-even analysis to optimize bit runs

    International Nuclear Information System (INIS)

    Kelly, J. Jr.

    1992-01-01

    Applying a technique known as break-even analysis during the bit selection process enables the operator to more definitively estimate drilling costs. The break-even chart can be used in a variety of ways to evaluate bit and operating parameter alternatives. Frequent application of this technique significantly improves the user's understanding of drilling economics and their ability to plan more effective drilling programs. This paper reports on several examples of drilling cost estimates obtained through application of the break-even analysis, which determines the bit performance required to match established drilling cost records in similar applications. It is especially helpful when new bit features are being considered for the first time. Two common examples with today's rolling cutter bits are changes from steel teeth to tungsten carbide inserts (TCI) and O-ring to metal bearing seals

  11. A Memristor as Multi-Bit Memory: Feasibility Analysis

    Directory of Open Access Journals (Sweden)

    O. Bass

    2015-06-01

    Full Text Available The use of emerging memristor materials for advanced electrical devices such as multi-valued logic is expected to outperform today's binary logic digital technologies. We show here an example for such non-binary device with the design of a multi-bit memory. While conventional memory cells can store only 1 bit, memristors-based multi-bit cells can store more information within single device thus increasing the information storage density. Such devices can potentially utilize the non-linear resistance of memristor materials for efficient information storage. We analyze the performance of such memory devices based on their expected variations in order to determine the viability of memristor-based multi-bit memory. A design of read/write scheme and a simple model for this cell, lay grounds for full integration of memristor multi-bit memory cell.

  12. Installation of MCNP on 64-bit parallel computers

    International Nuclear Information System (INIS)

    Meginnis, A.B.; Hendricks, J.S.; McKinney, G.W.

    1995-01-01

    The Monte Carlo radiation transport code MCNP has been successfully ported to two 64-bit workstations, the SGI and DEC Alpha. We found the biggest problem for installation on these machines to be Fortran and C mismatches in argument passing. Correction of these mismatches enabled, for the first time, dynamic memory allocation on 64-bit workstations. Although the 64-bit hardware is faster because 8-bytes are processed at a time rather than 4-bytes, we found no speed advantage in true 64-bit coding versus implicit double precision when porting an existing code to the 64-bit workstation architecture. We did find that PVM multiasking is very successful and represents a significant performance enhancement for scientific workstations

  13. A little bit of legal history

    CERN Multimedia

    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...

  14. A bit faster : ReedHycalog focuses new drill bit technology on the needs of western Canadian drillers

    Energy Technology Data Exchange (ETDEWEB)

    Wells, P.

    2009-06-15

    ReedHycalog, a division of National Oilwell Varco Inc., is advancing its drill bit technology and is setting performance records in an effort to meet the needs of drillers in western Canada. This article described the company's new drill bit technology. Through its motor series polycrystalline diamond cutter (PDC) bits, ReedHycalog developed and commercialized several unique and proprietary drill bit features that reduced variations in torque. This lowered the risk of stick-slip while improving lateral stability, directional control and drilling efficiency. The design of the motor series bits was reviewed along with laboratory and field testing. Smooth torque was identified as one of the greatest challenges when drilling with a drill bit on a directional assembly. Test results revealed that there are 4 distinct characteristics for optimal steerable motor performance, such as smooth torque control components (TCC) that were specifically positioned in the cone of the bit to prevent cutter over engagement reducing in torque fluctuations for optimal tool face control; optimized cutter backrakes that provided high penetration rates in rotating mode, while TCCs were optimized to control torque when sliding; gauge inserts for lateral control that provided a low-friction bearing surface; and laterally exposed gauge cutters that cleaned up the hole in rotating mode, and a tapered upper section that reduced gauge pad interference while in sliding mode. The motor series bits performed extremely well in the vertical, build and horizontal intervals with multiple operators. 1 ref., 3 figs.

  15. Conditions of using floating cranes for lifting sunken objects on inland waterways

    OpenAIRE

    Slobodan M. Radojević

    2012-01-01

    This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  16. Conditions of using floating cranes for lifting sunken objects on inland waterways

    Directory of Open Access Journals (Sweden)

    Slobodan M. Radojević

    2012-04-01

    Full Text Available This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  17. Floating seal system for rotary devices

    Science.gov (United States)

    Banasiuk, H.A.

    1983-08-23

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10[degree] to about 30[degree] in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device. 5 figs.

  18. Modern X86 assembly language programming 32-bit, 64-bit, SSE, and AVX

    CERN Document Server

    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

  19. Dispersion measurements from Sofar floats on the Iberian Abyssal plain

    International Nuclear Information System (INIS)

    Rees, J.M.; Gmitrowicz, M.

    1989-01-01

    Tracks of SOFAR floats launched on the Iberian Abyssal Plain are presented. The floats were launched in two groups in early October 1984 and mid-February 1985 to a nominal depth of 2500 m. Of these floats, 4 from the first deployment and 2 from the second functioned properly. Float signals were recorded by four autonomous listening stations at a depth of 1900 m. These preliminary results show the tracks of floats up to July 1986 and represent 3600 float days of information. The main task of the experiment was to especially study the dispersion of radioactive substances

  20. 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......-case. To the best of our knowledge, this is the first such representation which supports these operations by always reading strictly less than n bits. For redundant counters where we only need to represent numbers in the range [0,...,L] for some integer L bits, we define the efficiency...

  1. Economic Floating Waste Detectionfor Surface Cleaning Robots

    Directory of Open Access Journals (Sweden)

    Sumroengrit Jakkrit

    2017-01-01

    Full Text Available Removing waste out of water surface is a routine task and can be operated by using autonomous surface cleaning robots. This paper presents amethodoflaser-based floating waste detection for surface robot guidance when waste positions are unknown beforehand. Basing on concept of refraction and reflection of laser ray, the proposed laser-based technique is proven to be applicable on floating waste detection. The economic waste detector is constructed and mounted on the robot. Five DOF equations of motion are formulated for calculation of waste position incorporating distance measured by the laser and also the robot motion caused by external wind force as well as water surface tension. Experiments were conducted on a pond with calm water and results show that the presented economic waste detection successfully identify and locate position of plastic bottles floating on water surface within the range of 5 meters.

  2. Fitness Probability Distribution of Bit-Flip Mutation.

    Science.gov (United States)

    Chicano, Francisco; Sutton, Andrew M; Whitley, L Darrell; Alba, Enrique

    2015-01-01

    Bit-flip mutation is a common mutation operator for evolutionary algorithms applied to optimize functions over binary strings. In this paper, we develop results from the theory of landscapes and Krawtchouk polynomials to exactly compute the probability distribution of fitness values of a binary string undergoing uniform bit-flip mutation. We prove that this probability distribution can be expressed as a polynomial in p, the probability of flipping each bit. We analyze these polynomials and provide closed-form expressions for an easy linear problem (Onemax), and an NP-hard problem, MAX-SAT. We also discuss a connection of the results with runtime analysis.

  3. An Image Encryption Method Based on Bit Plane Hiding Technology

    Institute of Scientific and Technical Information of China (English)

    LIU Bin; LI Zhitang; TU Hao

    2006-01-01

    A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting "Exclusive-OR" operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effective.

  4. The Economics of BitCoin Price Formation

    OpenAIRE

    Pavel Ciaian; Miroslava Rajcaniova; d'Artis Kancs

    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...

  5. Description of signature scales in a floating wind turbine model wake subjected to varying turbulence intensity

    Science.gov (United States)

    Kadum, Hawwa; Rockel, Stanislav; Holling, Michael; Peinke, Joachim; Cal, Raul Bayon

    2017-11-01

    The wake behind a floating model horizontal axis wind turbine during pitch motion is investigated and compared to a fixed wind turbine wake. An experiment is conducted in an acoustic wind tunnel where hot-wire data are acquired at five downstream locations. At each downstream location, a rake of 16 hot-wires was used with placement of the probes increasing radially in the vertical, horizontal, and diagonally at 45 deg. In addition, the effect of turbulence intensity on the floating wake is examined by subjecting the wind turbine to different inflow conditions controlled through three settings in the wind tunnel grid, a passive and two active protocols, thus varying in intensity. The wakes are inspected by statistics of the point measurements, where the various length/time scales are considered. The wake characteristics for a floating wind turbine are compared to a fixed turbine, and uncovering its features; relevant as the demand for exploiting deep waters in wind energy is increasing.

  6. Optimal trajectory planning of free-floating space manipulator using differential evolution algorithm

    Science.gov (United States)

    Wang, Mingming; Luo, Jianjun; Fang, Jing; Yuan, Jianping

    2018-03-01

    The existence of the path dependent dynamic singularities limits the volume of available workspace of free-floating space robot and induces enormous joint velocities when such singularities are met. In order to overcome this demerit, this paper presents an optimal joint trajectory planning method using forward kinematics equations of free-floating space robot, while joint motion laws are delineated with application of the concept of reaction null-space. Bézier curve, in conjunction with the null-space column vectors, are applied to describe the joint trajectories. Considering the forward kinematics equations of the free-floating space robot, the trajectory planning issue is consequently transferred to an optimization issue while the control points to construct the Bézier curve are the design variables. A constrained differential evolution (DE) scheme with premature handling strategy is implemented to find the optimal solution of the design variables while specific objectives and imposed constraints are satisfied. Differ from traditional methods, we synthesize null-space and specialized curve to provide a novel viewpoint for trajectory planning of free-floating space robot. Simulation results are presented for trajectory planning of 7 degree-of-freedom (DOF) kinematically redundant manipulator mounted on a free-floating spacecraft and demonstrate the feasibility and effectiveness of the proposed method.

  7. FLOAT2 WP4: Development of Materials

    DEFF Research Database (Denmark)

    Esteves, Luis Pedro; Aarup, Bendt

    This report refers to complementary material testing to support the design and production of UHPC floaters for installation in the Wave Star Machine under FLOAT2 project. The main objective of WP4 is the characterization of mechanical properties of fiber-reinforced UHPC.......This report refers to complementary material testing to support the design and production of UHPC floaters for installation in the Wave Star Machine under FLOAT2 project. The main objective of WP4 is the characterization of mechanical properties of fiber-reinforced UHPC....

  8. Effects of Electrolyte on Floating Water Bridge

    OpenAIRE

    Hideo Nishiumi; Fumitaka Honda

    2009-01-01

    Fuchs found phenomena that when high voltage is applied to deionized water filled in two contacted beakers, a floating water bridge forms spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and N H 4 C l to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte A l 2 O 3 had no effect on the length of water bridge.

  9. Compact FPGA-based beamformer using oversampled 1-bit A/D converters

    DEFF Research Database (Denmark)

    Tomov, Borislav Gueorguiev; Jensen, Jørgen Arendt

    2005-01-01

    A compact medical ultrasound beamformer architecture that uses oversampled 1-bit analog-to-digital (A/D) converters is presented. Sparse sample processing is used, as the echo signal for the image lines is reconstructed in 512 equidistant focal points along the line through its in-phase and quadr......% of the available logic resources in a commercially available midrange FPGA, and to be able to operate at 129 MHz. Simulation of the architecture at 140 MHz provides images with a dynamic range approaching 60 dB for an excitation frequency of 3 MHz.......A compact medical ultrasound beamformer architecture that uses oversampled 1-bit analog-to-digital (A/D) converters is presented. Sparse sample processing is used, as the echo signal for the image lines is reconstructed in 512 equidistant focal points along the line through its in......-phase and quadrature components. That information is sufficient for presenting a B-mode image and creating a color flow map. The high sampling rate provides the necessary delay resolution for the focusing. The low channel data width (1-bit) makes it possible to construct a compact beamformer logic. The signal...

  10. Bit Error Rate Minimizing Channel Shortening Equalizers for Single Carrier Cyclic Prefixed Systems

    National Research Council Canada - National Science Library

    Martin, Richard K; Vanbleu, Koen; Ysebaert, Geert

    2007-01-01

    .... Previous work on channel shortening has largely been in the context of digital subscriber lines, a wireline system that allows bit allocation, thus it has focused on maximizing the bit rate for a given bit error rate (BER...

  11. Development of hybrid fluid jet/float polishing process

    Science.gov (United States)

    Beaucamp, Anthony T. H.; Namba, Yoshiharu; Freeman, Richard R.

    2013-09-01

    On one hand, the "float polishing" process consists of a tin lap having many concentric grooves, cut from a flat by single point diamond turning. This lap is rotated above a hydrostatic bearing spindle of high rigidity, damping and rotational accuracy. The optical surface thus floats above a thin layer of abrasive particles. But whilst surface texture can be smoothed to ~0.1nm rms (as measured by atomic force microscopy), this process can only be used on flat surfaces. On the other hand, the CNC "fluid jet polishing" process consists of pumping a mixture of water and abrasive particles to a converging nozzle, thus generating a polishing spot that can be moved along a tool path with tight track spacing. But whilst tool path feed can be moderated to ultra-precisely correct form error on freeform optical surfaces, surface finish improvement is generally limited to ~1.5nm rms (with fine abrasives). This paper reports on the development of a novel finishing method, that combines the advantages of "fluid jet polishing" (i.e. freeform corrective capability) with "float polishing" (i.e. super-smooth surface finish of 0.1nm rms or less). To come up with this new "hybrid" method, computational fluid dynamic modeling of both processes in COMSOL is being used to characterize abrasion conditions and adapt the process parameters of experimental fluid jet polishing equipment, including: (1) geometrical shape of nozzle, (2) position relative to the surface, (3) control of inlet pressure. This new process is aimed at finishing of next generation X-Ray / Gamma Ray focusing optics.

  12. Modern methods of drilling wells by large diameter bits and possible fields of application

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, W

    1970-04-01

    For the needs of up-to-date mining in construction of shafts and mining installations, large diameter wells are often used. In the near future, application of this type of well will be of great importance in the oil industry for stimulation of oil and gas recovery by atomic explosion. Such wells can be used for mineral extraction from subsea and other accessible deposits. The presented state of drilling techniques and technology by large diameter bits is described and similarities and differences with deep-well drilling are pointed out. Some economical data indicate the advantage of drilling by large-diameter bits in comparison with standard methods of construction of shafts and mining installations.

  13. A radiation-hardened 1K-bit dielectrically isolated random access memory

    International Nuclear Information System (INIS)

    Sandors, T.J.; Boarman, J.W.; Kasten, A.J.; Wood, G.M.

    1982-01-01

    Dielectric Isolation has been used for many years as the bipolar technology for latch-up free, radiation hardened integrated circuits in strategic systems. The state-of-the-art up to this point has been the manufacture of MSI functions containing a maximum of several hundred isolated components. This paper discusses a 1024 Bit Random Access Memory chip containing over 4000 dielectrically isolated components which has been designed for strategic radiation environments. The process utilized and the circuit design of the 1024 Bit RAM have been previously discussed. The techniques used are similar to those employed for the MX digital integrated circuits except for specific items required to make this a true LSI technology. These techniques, along with electrical and radiation data for the RAM, are presented

  14. Argo Float Data from the APDRC DAPPER Server, 1995-present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The floats are designed to drift at a fixed pressure (usually 1000 dbar) for 10 days. After this period, the floats move to a profiling pressure (usually between...

  15. Floating Inductance and FDNR Using Positive Polarity Current Conveyors

    Directory of Open Access Journals (Sweden)

    K. Pal

    2004-01-01

    Full Text Available A generalized circuit based on five positive polarity second-generation current conveyors is introduced. The circuit simulates a floating inductance, capacitor floatation circuit and floating fdnr. All these circuits use grounded capacitors.

  16. 2014 Metro, Oregon 4-Band 8 Bit Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are LiDAR orthorectified aerial photographs (8-bit GeoTIFF format) within the Oregon Lidar Consortium Portland project area. The imagery coverage is...

  17. Pseudo-random bit generator based on Chebyshev map

    Science.gov (United States)

    Stoyanov, B. P.

    2013-10-01

    In this paper, we study a pseudo-random bit generator based on two Chebyshev polynomial maps. The novel derivative algorithm shows perfect statistical properties established by number of statistical tests.

  18. Fast physical random bit generation with chaotic semiconductor lasers

    Science.gov (United States)

    Uchida, Atsushi; Amano, Kazuya; Inoue, Masaki; Hirano, Kunihito; Naito, Sunao; Someya, Hiroyuki; Oowada, Isao; Kurashige, Takayuki; Shiki, Masaru; Yoshimori, Shigeru; Yoshimura, Kazuyuki; Davis, Peter

    2008-12-01

    Random number generators in digital information systems make use of physical entropy sources such as electronic and photonic noise to add unpredictability to deterministically generated pseudo-random sequences. However, there is a large gap between the generation rates achieved with existing physical sources and the high data rates of many computation and communication systems; this is a fundamental weakness of these systems. Here we show that good quality random bit sequences can be generated at very fast bit rates using physical chaos in semiconductor lasers. Streams of bits that pass standard statistical tests for randomness have been generated at rates of up to 1.7 Gbps by sampling the fluctuating optical output of two chaotic lasers. This rate is an order of magnitude faster than that of previously reported devices for physical random bit generators with verified randomness. This means that the performance of random number generators can be greatly improved by using chaotic laser devices as physical entropy sources.

  19. 2015 Big Windy, Oregon 4-Band 8 Bit Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are LiDAR orthorectified aerial photographs (8-bit GeoTIFF format) within the Oregon Lidar Consortium Big Windy project area. The imagery coverage is...

  20. Secure self-calibrating quantum random-bit generator

    International Nuclear Information System (INIS)

    Fiorentino, M.; Santori, C.; Spillane, S. M.; Beausoleil, R. G.; Munro, W. J.

    2007-01-01

    Random-bit generators (RBGs) are key components of a variety of information processing applications ranging from simulations to cryptography. In particular, cryptographic systems require 'strong' RBGs that produce high-entropy bit sequences, but traditional software pseudo-RBGs have very low entropy content and therefore are relatively weak for cryptography. Hardware RBGs yield entropy from chaotic or quantum physical systems and therefore are expected to exhibit high entropy, but in current implementations their exact entropy content is unknown. Here we report a quantum random-bit generator (QRBG) that harvests entropy by measuring single-photon and entangled two-photon polarization states. We introduce and implement a quantum tomographic method to measure a lower bound on the 'min-entropy' of the system, and we employ this value to distill a truly random-bit sequence. This approach is secure: even if an attacker takes control of the source of optical states, a secure random sequence can be distilled

  1. Experimental bit commitment based on quantum communication and special relativity.

    Science.gov (United States)

    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.

  2. 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....

  3. Comparison and status of 32 bit backplane bus architectures

    International Nuclear Information System (INIS)

    Muller, K.D.

    1985-01-01

    With the introduction of 32 bit microprocessors several new 32 bit backplane bus architectures have been developed and are in the process for standardization. Among these are Future Bus (IEEE P896.1), VME-Bus (IEEE 1014), MULTIBUS II, Nu-Bus and Fastbus (IEEE 960). The paper describes and compares the main features of these bus architectures and mentions the status of national and international standardization efforts

  4. Hiding and feeding in floating seaweed: Floating seaweed clumps as possible refuges or feeding grounds for fishes

    Science.gov (United States)

    Vandendriessche, Sofie; Messiaen, Marlies; O'Flynn, Sarah; Vincx, Magda; Degraer, Steven

    2007-02-01

    Floating seaweed is considered to be an important habitat for juvenile fishes due to the provision of food, shelter, a visual orientation point and passive transport. The importance of the presence of the highly dynamical seaweed clumps from the North Sea to juvenile neustonic fishes was investigated by analysing both neuston samples (without seaweed) and seaweed samples concerning fish community structure, and length-frequency distributions and feeding habits of five associated fish species. While the neustonic fish community was mainly seasonally structured, the seaweed-associated fish community was more complex: the response of the associated fish species to environmental variables was species specific and probably influenced by species interactions, resulting in a large multivariate distance between the samples dominated by Chelon labrosus and the samples dominated by Cyclopterus lumpus, Trachurus trachurus and Ciliata mustela. The results of the stomach analysis confirmed that C. lumpus is a weedpatch specialist that has a close spatial affinity with the seaweed and feeds intensively on the seaweed-associated invertebrate fauna. Similarly, C. mustela juveniles also fed on the seaweed fauna, but in a more opportunistic way. The shape of the size-frequency distribution suggested enhanced growth when associated with floating seaweed. Chelon labrosus and T. trachurus juveniles were generally large in seaweed samples, but large individuals were also encountered in the neuston. The proportion of associated invertebrate fauna in their diet was of minor importance, compared to the proportions in C. lumpus. Individuals of Syngnathus rostellatus mainly fed on planktonic invertebrates but had a discontinuous size-frequency distribution, suggesting that some of the syngnathids were carried with the seaweed upon detachment and stayed associated. Floating seaweeds can therefore be regarded as ephemeral habitats shared between several fish species (mainly juveniles) that use

  5. 14 CFR 25.753 - Main float design.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Main float design. 25.753 Section 25.753 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Floats and Hulls § 25.753 Main float design...

  6. Validation of salinity data from ARGO floats: Comparison between the older ARGO floats and that of later deployments

    Digital Repository Service at National Institute of Oceanography (India)

    Youn, Y.-H.; Lee, H.; Chang, Y.-S.; Pankajakshan, T.

    Continued observation of ARGO floats or years (about 4 years) makes the conductivity sensor more vulnerable to fouling by marine life and associated drift in salinity measurements. In this paper, we address this issue by making use of floats...

  7. Dealing with Human Death: The Floating Perspective.

    Science.gov (United States)

    Kenyon, Gary M.

    1991-01-01

    Explores approach to dealing with human death. Describes floating perspective, based on insights from Choron and Jaspers, as suggesting it is possible to deal with human death by refraining from taking ultimate position on the problem. Position encourages openness to death. Examines role of anxiety and describes possible meaningful outcomes of…

  8. Gastroretentive Floating Microspheres of Silymarin: Preparation and ...

    African Journals Online (AJOL)

    Erah

    simulated gastric fluid for at least 12 h, and, therefore, could potentially ... systems (GRFDDS) have a bulk density ... The objective of this work was to develop and characterise gastroretentive floating microspheres of silymarin which, following oral administration, would exhibit .... hydrochloric acid to maintain sink conditions.

  9. Reis kosmosesse : [Floating-kambrist] / Marika Makarova

    Index Scriptorium Estoniae

    Makarova, Marika

    2011-01-01

    Ameerika psühholoogi John C. Lilly poolt kasutusele võetud Floating-kambrist ehk hõljumisvannist, mis aeglustab ajulaineid ning seeläbi aitab vähendada lihaspinget, stressi, ärevust, peavalusid, vererõhku ning parandada und, selgroo- ja kaelavigastusi, suurendada loovust ja heaolu jne

  10. A novel floating offshore wind turbine concept

    DEFF Research Database (Denmark)

    Vita, Luca; Schmidt Paulsen, Uwe; Friis Pedersen, Troels

    2009-01-01

    This paper will present a novel concept of a floating offshore wind turbine. The new concept is intended for vertical-axis wind turbine technology. The main purpose is to increase simplicity and to reduce total costs of an installed offshore wind farm. The concept is intended for deep water...... and large size turbines....

  11. Effects of Electrolyte on Floating Water Bridge

    Directory of Open Access Journals (Sweden)

    Hideo Nishiumi

    2009-01-01

    spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and NH4Cl to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte Al2O3 had no effect on the length of water bridge.

  12. Floating car data for traffic monitoring

    DEFF Research Database (Denmark)

    Torp, Kristian; Lahrmann, Harry Spaabæk

    2005-01-01

    This paper describes a complete prototype system that uses Floating Car Data (FCD) for both automatic and manual detection of queues in traffic. The system is developed under EU’s Tempo program. The systems consists of small hardware units placed in mobile traffic report units (we use taxis...

  13. Two New Families of Floating FDNR Circuits

    Directory of Open Access Journals (Sweden)

    Ahmed M. Soliman

    2010-01-01

    Full Text Available Two new configurations for realizing ideal floating frequency-dependent negative resistor elements (FDNR are introduced. The proposed circuits are symmetrical and are realizable by four CCII or ICCII or a combination of both. Each configuration is realizable by eight different circuits. Simulation results are included to support the theory.

  14. Floating plant dominance as a stable state

    NARCIS (Netherlands)

    Scheffer, M.; Szabo, S.; Gragnani, A.; Nes, van E.H.; Rinaldi, S.; Kautsky, N.; Norberg, J.; Roijackers, R.M.M.; Franken, R.J.M.

    2003-01-01

    The authors demonstrate that floating-plant dominance can be a self-stabilizing ecosystem state, which may explain its notorious persistence in many situations. Their results, based on experiments, field data, and models (in Dutch ditches and Lake Kariba, Zimbabwe), represent evidence for

  15. Floating convection barrier for evaporation source

    International Nuclear Information System (INIS)

    1975-01-01

    A floating matrix of titanium in an uranium evaporation source, melted by an electron beam, serves as a barrier for preventing cooler material from reaching the evaporation area. This construction allows a big volume of melted uranium to be present and new uranium to be furnished in regulated intervals without manual intervention

  16. Gastroretentive Floating Microspheres of Silymarin: Preparation and ...

    African Journals Online (AJOL)

    Methods: Cellulose microspheres – formulated with hydroxylpropyl methylcellulose (HPMC) and ethyl cellulose (EC) – and Eudragit microspheres – formulated with Eudragit® S 100 (ES) and Eudragit® RL (ERL) - were prepared by an emulsion-solvent evaporation method. The floating microspheres were evaluated for flow ...

  17. Critical Point Dryer: Tousimis 916B Series C

    Data.gov (United States)

    Federal Laboratory Consortium — Description:CORAL Name: Critical Point DryerThis system utilizes CO 2to dry fragile suspended and floating structures Specifications / Capabilities:Wafer size up to...

  18. Development of floating strip micromegas detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bortfeldt, Jonathan

    2014-04-28

    Micromegas are high-rate capable, high-resolution micro-pattern gaseous detectors. Square meter sized resistive strip Micromegas are foreseen as replacement of the currently used precision tracking detectors in the Small Wheel, which is part of the forward region of the ATLAS muon spectrometer. The replacement is necessary to ensure tracking and triggering performance of the muon spectrometer after the luminosity increase of the Large Hadron Collider beyond its design value of 10{sup 34} cm{sup -2}s{sup -1} around 2020. In this thesis a novel discharge tolerant floating strip Micromegas detector is presented and described. By individually powering copper anode strips, the effects of a discharge are confined to a small region of the detector. This reduces the impact of discharges on the efficiency by three orders of magnitude, compared to a standard Micromegas. The physics of the detector is studied and discussed in detail. Several detectors are developed: A 6.4 x 6.4 cm{sup 2} floating strip Micromegas with exchangeable SMD capacitors and resistors allows for an optimization of the floating strip principle. The discharge behavior is investigated on this device in depth. The microscopic structure of discharges is quantitatively explained by a detailed detector simulation. A 48 x 50 cm{sup 2} floating strip Micromegas is studied in high energy pion beams. Its homogeneity with respect to pulse height, efficiency and spatial resolution is investigated. The good performance in high-rate background environments is demonstrated in cosmic muon tracking measurements with a 6.4 x 6.4 cm{sup 2} floating strip Micromegas under lateral irradiation with 550 kHz 20 MeV proton beams. A floating strip Micromegas doublet with low material budget is developed for ion tracking without limitations from multiple scattering in imaging applications during medical ion therapy. Highly efficient tracking of 20 MeV protons at particle rates of 550 kHz is possible. The reconstruction of the

  19. Development of floating strip micromegas detectors

    International Nuclear Information System (INIS)

    Bortfeldt, Jonathan

    2014-01-01

    Micromegas are high-rate capable, high-resolution micro-pattern gaseous detectors. Square meter sized resistive strip Micromegas are foreseen as replacement of the currently used precision tracking detectors in the Small Wheel, which is part of the forward region of the ATLAS muon spectrometer. The replacement is necessary to ensure tracking and triggering performance of the muon spectrometer after the luminosity increase of the Large Hadron Collider beyond its design value of 10 34 cm -2 s -1 around 2020. In this thesis a novel discharge tolerant floating strip Micromegas detector is presented and described. By individually powering copper anode strips, the effects of a discharge are confined to a small region of the detector. This reduces the impact of discharges on the efficiency by three orders of magnitude, compared to a standard Micromegas. The physics of the detector is studied and discussed in detail. Several detectors are developed: A 6.4 x 6.4 cm 2 floating strip Micromegas with exchangeable SMD capacitors and resistors allows for an optimization of the floating strip principle. The discharge behavior is investigated on this device in depth. The microscopic structure of discharges is quantitatively explained by a detailed detector simulation. A 48 x 50 cm 2 floating strip Micromegas is studied in high energy pion beams. Its homogeneity with respect to pulse height, efficiency and spatial resolution is investigated. The good performance in high-rate background environments is demonstrated in cosmic muon tracking measurements with a 6.4 x 6.4 cm 2 floating strip Micromegas under lateral irradiation with 550 kHz 20 MeV proton beams. A floating strip Micromegas doublet with low material budget is developed for ion tracking without limitations from multiple scattering in imaging applications during medical ion therapy. Highly efficient tracking of 20 MeV protons at particle rates of 550 kHz is possible. The reconstruction of the track inclination in a single

  20. Greenhouse heating with a fresh water floating collector solar pond

    International Nuclear Information System (INIS)

    Arbel, A.; Sokolov, M.

    1991-01-01

    The fresh water floating collector solar pond was investigated both experimentally and theoretically in a previous work, and it is now matched, by simulation, with the heat load requirements of a greenhouse. Results of the simulation indicate that such a pond is a potential energy source for greenhouse heating. This is especially true when the material properties are such that solar absorption and storage are enhanced. This paper reports that to demonstrate this point, three sets of collectors constructed with materials of different physical (radiation) properties were tested. One set is constructed of common materials which are readily available and are normally used as covers for greenhouses. The second set made of improved materials which are also available but have a smaller long-wave transmittance. The last set made of ideal material which additionally possesses selective radiation absorption properties. Collectors made of ideal materials make a superior solar pond; thus, manufacturing films with improved properties should become a worthwhile challenge for the agricultural polyethylene-films industry. Preliminary economic studies indicate that even with the low oil (<$20/Bbl) prices which exist between 1986-1989, the fresh water floating collectors solar pond provides an economically attractive alternative to the conventional oil-burning heating system. This is especially true in mild climate areas and when the large initial investment is justified by long-term greenhouse utilization planning

  1. Wave Energy, Lever Operated Pivoting Float LOPF Study

    DEFF Research Database (Denmark)

    Margheritini, Lucia

    The fully instrumented Resen Waves Lever Operated Pivoting Float LOPF wave energy buoy model has gone through the first stage of testing in regular waves in scale 1:25 of the North Sea wave conditions, in the 3D deep wave basin at the Hydraulic and Coastal Engineering Laboratory of Aalborg...... University in Denmark. The model size was 60cm W x 90cm L x 21cm H. The 60 cm width pointed towards the wave front. The LOPF buoy is characterized by a simple mechanical design with few moving parts and direct electrical output and it is taut moored to the sea bed, so all forces are referenced to the seabed...... for maximum energy output in regular as well as irregular waves. During storms the buoy pivots and streamlines itself to minimize loads on the mooring line. A conservative estimate shows that a full scale system for North Sea conditions has a float size width of 15 m that will, with 60% generator efficiency...

  2. SpecBit, DecayBit and PrecisionBit. GAMBIT modules for computing mass spectra, particle decay rates and precision observables

    Energy Technology Data Exchange (ETDEWEB)

    Athron, Peter; Balazs, Csaba [Monash University, School of Physics and Astronomy, Melbourne, VIC (Australia); Australian Research Council Centre of Excellence for Particle Physics at the Tera-scale (Australia); Dal, Lars A.; Gonzalo, Tomas E. [University of Oslo, Department of Physics, Oslo (Norway); Edsjoe, Joakim; Farmer, Ben [AlbaNova University Centre, Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Stockholm University, Department of Physics, Stockholm (Sweden); Kvellestad, Anders [NORDITA, Stockholm (Sweden); McKay, James; Scott, Pat [Imperial College London, Department of Physics, Blackett Laboratory, London (United Kingdom); Putze, Antje [Universite de Savoie, CNRS, LAPTh, Annecy-le-Vieux (France); Rogan, Chris [Harvard University, Department of Physics, Cambridge, MA (United States); Weniger, Christoph [University of Amsterdam, GRAPPA, Institute of Physics, Amsterdam (Netherlands); White, Martin [Australian Research Council Centre of Excellence for Particle Physics at the Tera-scale (Australia); University of Adelaide, Department of Physics, Adelaide, SA (Australia); Collaboration: The GAMBIT Models Workgroup

    2018-01-15

    We present the GAMBIT modules SpecBit, DecayBit and PrecisionBit. Together they provide a new framework for linking publicly available spectrum generators, decay codes and other precision observable calculations in a physically and statistically consistent manner. This allows users to automatically run various combinations of existing codes as if they are a single package. The modular design allows software packages fulfilling the same role to be exchanged freely at runtime, with the results presented in a common format that can easily be passed to downstream dark matter, collider and flavour codes. These modules constitute an essential part of the broader GAMBIT framework, a major new software package for performing global fits. In this paper we present the observable calculations, data, and likelihood functions implemented in the three modules, as well as the conventions and assumptions used in interfacing them with external codes. We also present 3-BIT-HIT, a command-line utility for computing mass spectra, couplings, decays and precision observables in the MSSM, which shows how the three modules can easily be used independently of GAMBIT. (orig.)

  3. SpecBit, DecayBit and PrecisionBit: GAMBIT modules for computing mass spectra, particle decay rates and precision observables

    Science.gov (United States)

    Athron, Peter; Balázs, Csaba; Dal, Lars A.; Edsjö, Joakim; Farmer, Ben; Gonzalo, Tomás E.; Kvellestad, Anders; McKay, James; Putze, Antje; Rogan, Chris; Scott, Pat; Weniger, Christoph; White, Martin

    2018-01-01

    We present the GAMBIT modules SpecBit, DecayBit and PrecisionBit. Together they provide a new framework for linking publicly available spectrum generators, decay codes and other precision observable calculations in a physically and statistically consistent manner. This allows users to automatically run various combinations of existing codes as if they are a single package. The modular design allows software packages fulfilling the same role to be exchanged freely at runtime, with the results presented in a common format that can easily be passed to downstream dark matter, collider and flavour codes. These modules constitute an essential part of the broader GAMBIT framework, a major new software package for performing global fits. In this paper we present the observable calculations, data, and likelihood functions implemented in the three modules, as well as the conventions and assumptions used in interfacing them with external codes. We also present 3-BIT-HIT, a command-line utility for computing mass spectra, couplings, decays and precision observables in the MSSM, which shows how the three modules can easily be used independently of GAMBIT.

  4. Sleep stage classification with low complexity and low bit rate.

    Science.gov (United States)

    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.

  5. Unsteady aerodynamic analysis for offshore floating wind turbines under different wind conditions.

    Science.gov (United States)

    Xu, B F; Wang, T G; Yuan, Y; Cao, J F

    2015-02-28

    A free-vortex wake (FVW) model is developed in this paper to analyse the unsteady aerodynamic performance of offshore floating wind turbines. A time-marching algorithm of third-order accuracy is applied in the FVW model. Owing to the complex floating platform motions, the blade inflow conditions and the positions of initial points of vortex filaments, which are different from the fixed wind turbine, are modified in the implemented model. A three-dimensional rotational effect model and a dynamic stall model are coupled into the FVW model to improve the aerodynamic performance prediction in the unsteady conditions. The effects of floating platform motions in the simulation model are validated by comparison between calculation and experiment for a small-scale rigid test wind turbine coupled with a floating tension leg platform (TLP). The dynamic inflow effect carried by the FVW method itself is confirmed and the results agree well with the experimental data of a pitching transient on another test turbine. Also, the flapping moment at the blade root in yaw on the same test turbine is calculated and compares well with the experimental data. Then, the aerodynamic performance is simulated in a yawed condition of steady wind and in an unyawed condition of turbulent wind, respectively, for a large-scale wind turbine coupled with the floating TLP motions, demonstrating obvious differences in rotor performance and blade loading from the fixed wind turbine. The non-dimensional magnitudes of loading changes due to the floating platform motions decrease from the blade root to the blade tip. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  6. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data.

    Science.gov (United States)

    Ran, Bin; Song, Li; Zhang, Jian; Cheng, Yang; Tan, Huachun

    2016-01-01

    Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%.

  7. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data.

    Directory of Open Access Journals (Sweden)

    Bin Ran

    Full Text Available Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%.

  8. Test plan for core sampling drill bit temperature monitor

    International Nuclear Information System (INIS)

    Francis, P.M.

    1994-01-01

    At WHC, one of the functions of the Tank Waste Remediation System division is sampling waste tanks to characterize their contents. The push-mode core sampling truck is currently used to take samples of liquid and sludge. Sampling of tanks containing hard salt cake is to be performed with the rotary-mode core sampling system, consisting of the core sample truck, mobile exhauster unit, and ancillary subsystems. When drilling through the salt cake material, friction and heat can be generated in the drill bit. Based upon tank safety reviews, it has been determined that the drill bit temperature must not exceed 180 C, due to the potential reactivity of tank contents at this temperature. Consequently, a drill bit temperature limit of 150 C was established for operation of the core sample truck to have an adequate margin of safety. Unpredictable factors, such as localized heating, cause this buffer to be so great. The most desirable safeguard against exceeding this threshold is bit temperature monitoring . This document describes the recommended plan for testing the prototype of a drill bit temperature monitor developed for core sampling by Sandia National Labs. The device will be tested at their facilities. This test plan documents the tests that Westinghouse Hanford Company considers necessary for effective testing of the system

  9. Diamond bits for directional drilling of wells and technology of using them

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, V P; Steblev, B Ye; Sumaneyev, N N

    1979-01-01

    Characteristics are presented for a diamond bit for directional drilling ADN-08. Technology of using it is described, as well as cutter bits for directional drilling. Based on specially developed technique, the economic effect of using the diamond bits is calculated. This indicates that the use of the diamond bits in rocks of the VIII category significantly improves the quality of directional drilling.

  10. Voltage-Controlled Floating Resistor Using DDCC

    Directory of Open Access Journals (Sweden)

    M. Kumngern

    2011-04-01

    Full Text Available This paper presents a new simple configuration to realize the voltage-controlled floating resistor, which is suitable for integrated circuit implementation. The proposed resistor is composed of three main components: MOS transistor operating in the non-saturation region, DDCC, and MOS voltage divider. The MOS transistor operating in the non-saturation region is used to configure a floating linear resistor. The DDCC and the MOS transistor voltage divider are used for canceling the nonlinear component term of MOS transistor in the non-saturation region to obtain a linear current/voltage relationship. The DDCC is employed to provide a simple summer of the circuit. This circuit offers an ease for realizing the voltage divider circuit and the temperature effect that includes in term of threshold voltage can be compensated. The proposed configuration employs only 16 MOS transistors. The performances of the proposed circuit are simulated with PSPICE to confirm the presented theory.

  11. Floating Gate CMOS Dosimeter With Frequency Output

    Science.gov (United States)

    Garcia-Moreno, E.; Isern, E.; Roca, M.; Picos, R.; Font, J.; Cesari, J.; Pineda, A.

    2012-04-01

    This paper presents a gamma radiation dosimeter based on a floating gate sensor. The sensor is coupled with a signal processing circuitry, which furnishes a square wave output signal, the frequency of which depends on the total dose. Like any other floating gate dosimeter, it exhibits zero bias operation and reprogramming capabilities. The dosimeter has been designed in a standard 0.6 m CMOS technology. The whole dosimeter occupies a silicon area of 450 m250 m. The initial sensitivity to a radiation dose is Hz/rad, and to temperature and supply voltage is kHz/°C and 0.067 kHz/mV, respectively. The lowest detectable dose is less than 1 rad.

  12. Fresh water generators onboard a floating platform

    International Nuclear Information System (INIS)

    Tewari, P.K.; Verma, R.K.; Misra, B.M.; Sadhulkan, H.K.

    1997-01-01

    A dependable supply of fresh water is essential for any ocean going vessel. The operating and maintenance personnel on offshore platforms and marine structures also require a constant and regular supply of fresh water to meet their essential daily needs. A seawater thermal desalination unit onboard delivers good quality fresh water from seawater. The desalination units developed by Bhabha Atomic Research Centre (BARC) suitable for ocean going vessels and offshore platforms have been discussed. Design considerations of such units with reference to floating platforms and corrosive environments have been presented. The feasibility of coupling a low temperature vacuum evaporation (LTVE) desalination plant suitable for an onboard floating platform to a PHWR nuclear power plant has also been discussed. (author). 1 ref., 3 figs, 2 tabs

  13. Ships as future floating farm systems?

    Science.gov (United States)

    Moustafa, Khaled

    2018-04-03

    Environmental and agriculture challenges such as severe drought, desertification, sprawling cities and shrinking arable lands in large regions in the world compel us to think about alternative and sustainable farming systems. Ongoing projects to build floating cities in the sea suggest that building specific ships for farming purposes (as farming ships or farming boats) would also be attainable to introduce new farming surfaces and boost food production worldwide to cope with food insecurity issues.

  14. Traumatic Floating Clavicle: A Case Report

    Directory of Open Access Journals (Sweden)

    Choo CY

    2012-07-01

    Full Text Available Shoulder girdle injuries after high energy traumatic impacts to the shoulder have been well documented. Based on the series of 1603 injuries of the shoulder girdle reported by Cave and colleagues, 85% of the dislocations were glenohumeral, 12% acromioclavicular and 3% sternoclavicular. Less frequently described are injuries involving both the sternoclavicular and acromioclavicular joints simultaneously in one extremity. The present case report discusses a case of traumatic floating clavicle associated with ipsilateral forearm and wrist injury which was treated surgically.

  15. Floating nuclear power plant safety assurance principles

    International Nuclear Information System (INIS)

    Zvonarev, B.M.; Kuchin, N.L.; Sergeev, I.V.

    1993-01-01

    In the north regions of the Russian federation and low density population areas, there is a real necessity for ecological clean energy small power sources. For this purpose, floating nuclear power plants, designed on the basis of atomic ship building engineering, are being conceptualized. It is possible to use the ship building plants for the reactor purposes. Issues such as radioactive waste management are described

  16. Security bound of cheat sensitive quantum bit commitment.

    Science.gov (United States)

    He, Guang Ping

    2015-03-23

    Cheat sensitive quantum bit commitment (CSQBC) loosens the security requirement of quantum bit commitment (QBC), so that the existing impossibility proofs of unconditionally secure QBC can be evaded. But here we analyze the common features in all existing CSQBC protocols, and show that in any CSQBC having these features, the receiver can always learn a non-trivial amount of information on the sender's committed bit before it is unveiled, while his cheating can pass the security check with a probability not less than 50%. The sender's cheating is also studied. The optimal CSQBC protocols that can minimize the sum of the cheating probabilities of both parties are found to be trivial, as they are practically useless. We also discuss the possibility of building a fair protocol in which both parties can cheat with equal probabilities.

  17. Security bound of cheat sensitive quantum bit commitment

    Science.gov (United States)

    He, Guang Ping

    2015-03-01

    Cheat sensitive quantum bit commitment (CSQBC) loosens the security requirement of quantum bit commitment (QBC), so that the existing impossibility proofs of unconditionally secure QBC can be evaded. But here we analyze the common features in all existing CSQBC protocols, and show that in any CSQBC having these features, the receiver can always learn a non-trivial amount of information on the sender's committed bit before it is unveiled, while his cheating can pass the security check with a probability not less than 50%. The sender's cheating is also studied. The optimal CSQBC protocols that can minimize the sum of the cheating probabilities of both parties are found to be trivial, as they are practically useless. We also discuss the possibility of building a fair protocol in which both parties can cheat with equal probabilities.

  18. Collector floating potentials in a discharge plasma

    International Nuclear Information System (INIS)

    Cercek, M.; Gyergyek, T.

    1999-01-01

    We present the results of a study on electrode floating potential formation in a hot-cathode discharge plasma. The electron component of the plasma is composed from two populations. The high temperature component develops from primary electrons and the cool component from secondary electrons born by ionisation of cold neutral gas. A static, kinetic plasma-sheath model is use to calculate the pre-sheath potential and the floating potential of the electrode. For hot primary electrons a truncated Maxwellian distribution is assumed. The plasma system is also modelled numerically with a dynamic, electrostatic particle simulation. The plasma source injects temporally equal fluxes of ions and electrons with half-Maxwellian velocities. Again, the hot electron distribution is truncated in the high velocity tail. The plasma parameters, such as ion temperature and mass, electron temperatures, discharge voltages, etc. correspond to experimental values. The experimental measurements of the electrode floating potential are performed in weakly magnetised plasma produced with hot cathode discharge in argon gas. Theoretical, simulation and experimental results are compared and they agree very well.(author)

  19. Turbomachinery systems for floating production applications

    Energy Technology Data Exchange (ETDEWEB)

    Windt, Jonathan P.; Kurz, Rainer [Solar Turbines Incorporated, San Diego, CA (United States)

    2008-07-01

    Since 1995 there has been a dramatic increase in oil and gas exploration and production using floating platforms in deeper waters located further offshore. This exploration started with tension leg platforms, progressed through SPARs and Semi-Submersibles, and later evolved into Floating Production Storage and Offloading (FPSO) vessels. Turbomachinery equipment installed on a floating platform or vessel will be expected to operate in the same manner as a land based machine, but in a variety of climate and environmental conditions that now includes motion. To operate successfully, specific design considerations for the turbo-machinery packages are required. It is critical to take into account the type of vessel, the expected list, trim and dynamic motion angles, the dynamic forces applied, the expected deck deflection as a result of those forces, understand the applicable class requirement, and where the equipment will be located on the vessel. This information is then translated into the design conditions to determine the type of mounting method to be used to attach the turbo-machinery package to the deck, the expected accelerations for structural analysis, and oil tank and system designs for fluid management. Furthermore, compressor designs need to allow utmost flexibility to adapt to changing operating conditions. (author)

  20. Hanford coring bit temperature monitor development testing results report

    International Nuclear Information System (INIS)

    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

  1. 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....

  2. Bit-wise arithmetic coding for data compression

    Science.gov (United States)

    Kiely, A. B.

    1994-01-01

    This article examines the problem of compressing a uniformly quantized independent and identically distributed (IID) source. We present a new compression technique, bit-wise arithmetic coding, that assigns fixed-length codewords to the quantizer output and uses arithmetic coding to compress the codewords, treating the codeword bits as independent. We examine the performance of this method and evaluate the overhead required when used block-adaptively. Simulation results are presented for Gaussian and Laplacian sources. This new technique could be used as the entropy coder in a transform or subband coding system.

  3. Cloning the entanglement of a pair of quantum bits

    International Nuclear Information System (INIS)

    Lamoureux, Louis-Philippe; Navez, Patrick; Cerf, Nicolas J.; Fiurasek, Jaromir

    2004-01-01

    It is shown that any quantum operation that perfectly clones the entanglement of all maximally entangled qubit pairs cannot preserve separability. This 'entanglement no-cloning' principle naturally suggests that some approximate cloning of entanglement is nevertheless allowed by quantum mechanics. We investigate a separability-preserving optimal cloning machine that duplicates all maximally entangled states of two qubits, resulting in 0.285 bits of entanglement per clone, while a local cloning machine only yields 0.060 bits of entanglement per clone

  4. Radioactive tracer system to indicate drill bit wear or failure

    International Nuclear Information System (INIS)

    Fries, B.A.

    1975-01-01

    A radioactive tracer system for indicating drill bit wear or failure utilizing radioactive krypton 85 in clathrate form, in the form of water-soluble kryptonates, or dissolved grease, is described. Preferably the radioactive krypton is placed so that when drill bit wear or failure occurs, the radioactive krypton 85 is relased and effectively becomes diffused in the circulating drilling fluid. At the surface, the radioactive krypton 85 gas is separated from the circulating drilling fluid by gas-mud separating means and is transported as a gas to a counting chamber where an accurate radioactivity count of beta rays released from the krypton is obtained. (Patent Office Record)

  5. How to deal with malleability of BitCoin transactions

    OpenAIRE

    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...

  6. Generating bit reversed numbers for calculating fast fourier transform

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.

    prerequisite of these methods are that data elements be available for shuffling in an array. Thus in a software environment, if the input data values are to be read from a file, reordering can be done only after al1 the values have been read into the array.... Alternately, data values can be read and placed directly at respective bit reversed positions by generating bit reversed addresses. Such a method can help in real-time data acquisition and FFT calculation. Thus, an efficient method of generating sequence...

  7. 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.

  8. Floating Oil-Spill Containment Device

    Science.gov (United States)

    Jones, Jack A.

    2012-01-01

    Previous oil containment booms have an open top that allows natural gas to escape, and have significant oil leakage due to wave action. Also, a subsea pyramid oil trap exists, but cannot move relative to moving oil plumes from deepsea oil leaks. The solution is to have large, moveable oil traps. One version floats on the sea surface and has a flexible tarp cover and a lower weighted skirt to completely entrap the floating oil and natural gas. The device must have at least three sides with boats pulling at each apex, and sonar or other system to track the slowly moving oil plume, so that the boats can properly locate the booms. The oil trap device must also have a means for removal of the oil and the natural gas. A second design version has a flexible pyramid cover that is attached by lines to ballast on the ocean floor. This is similar to fixed, metal pyramid oil capture devices in the Santa Barbara Channel off the coast of California. The ballast lines for the improved design, however, would have winches that can move the pyramid to always be located above the oil and gas plume. A third design is a combination of the first two. It uses a submerged pyramid to trap oil, but has no anchor and uses boats to locate the trap. It has ballast weights located along the bottom of the tarp and/or at the corners of the trap. The improved floating oil-spill containment device has a large floating boom and weighted skirt surrounding the oil and gas entrapment area. The device is triangular (or more than three sides) and has a flexible tarp cover with a raised gas vent area. Boats pull on the apex of the triangles to maintain tension and to allow the device to move to optimum locations to trap oil and gas. The gas is retrieved from a higher buoyant part of the tarp, and oil is retrieved from the floating oil layer contained in the device. These devices can be operated in relatively severe weather, since waves will break over the devices without causing oil leaking. Also, natural

  9. Optimal Configurations of Wave Energy Converter Arrays with a Floating Body

    Directory of Open Access Journals (Sweden)

    Zhang Wanchao

    2016-10-01

    Full Text Available An array of floating point-absorbing wave energy converters (WECs is usually employed for extracting efficiently ocean wave energy. For deep water environment, it is more feasible and convenient to connect the absorbers array with a floating body, such as a semi-submersible bottom-moored disk, whose function is to act as the virtual seabed. In the present work, an array of identical floating symmetrically distributed cylinders in a coaxial moored disk as a wave energy device is proposed The power take-off (PTO system in the wave energy device is assumed to be composed of a linear/nonlinear damper activated by the buoys heaving motion. Hydrodynamic analysis of the examined floating system is implemented in frequency domain. Hydrodynamic interferences between the oscillating bodies are accounted for in the corresponding coupled equations. The array layouts under the constraint of the disk, incidence wave directions, separating distance between the absorbers and the PTO damping are considered to optimize this kind of WECs. Numerical results with regular waves are presented and discussed for the axisymmetric system utilizing heave mode with these interaction factors, in terms of a specific numbers of cylinders and expected power production.

  10. Physical implication of transition voltage in organic nano-floating-gate nonvolatile memories

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shun; Gao, Xu, E-mail: wangsd@suda.edu.cn, E-mail: gaoxu@suda.edu.cn; Zhong, Ya-Nan; Zhang, Zhong-Da; Xu, Jian-Long; Wang, Sui-Dong, E-mail: wangsd@suda.edu.cn, E-mail: gaoxu@suda.edu.cn [Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu 215123 (China)

    2016-07-11

    High-performance pentacene-based organic field-effect transistor nonvolatile memories, using polystyrene as a tunneling dielectric and Au nanoparticles as a nano-floating-gate, show parallelogram-like transfer characteristics with a featured transition point. The transition voltage at the transition point corresponds to a threshold electric field in the tunneling dielectric, over which stored electrons in the nano-floating-gate will start to leak out. The transition voltage can be modulated depending on the bias configuration and device structure. For p-type active layers, optimized transition voltage should be on the negative side of but close to the reading voltage, which can simultaneously achieve a high ON/OFF ratio and good memory retention.

  11. Reliability-based dynamic positioning of floating vessels with riser and mooring system

    DEFF Research Database (Denmark)

    Fang, Shaoji; Leira, Bernt J.; Blanke, Mogens

    2011-01-01

    To maintain safety of a floating vessel with associated slender components such as risers and mooring line, the vessel is normally kept within a limited region. To specify a safe position in that region, this paper suggests a new position chasing algorithm with the consideration of both riser ang...... to their criticality. An optimal position set-point is produced by minimization of the value of the cost function. Numerical simulations show the effectiveness of the proposed algorithm....

  12. Investigation of Tank 241-AW-104 Composite Floating Layer

    Energy Technology Data Exchange (ETDEWEB)

    Meznarich, H. K. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Bolling, S. D. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Lachut, J. S. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States); Cooke, G. A. [Washington River Protection Solutions LLC (WRPS), Richland, WA (United States)

    2018-02-27

    Seven grab samples and one field blank were taken from Tank 241-AW-104 (AW-104) on June 2, 2017, and received at 222-S Laboratory on June 5, 2017. A visible layer with brown solids was observed floating on the top of two surface tank waste samples (4AW-17-02 and 4AW 17 02DUP). The floating layer from both samples was collected, composited, and submitted for chemical analyses and solid phase characterization in order to understand the composition of the floating layer. Tributyl phosphate and tridecane were higher in the floating layer than in the aqueous phase. Density in the floating layer was slightly lower than the mean density of all grab samples. Sodium nitrate and sodium carbonate were major components with a trace of gibbsite and very small size agglomerates were present in the solids of the floating layer. The supernate consisted of organics, soluble salt, and particulates.

  13. Refinements of multi-track Viterbi bit-detection

    NARCIS (Netherlands)

    Hekstra, A.P.; Coene, W.M.J.; Immink, A.H.J.

    2006-01-01

    In optical storage, data can be arranged on the disc in a meta-spiral consisting of a large number of bit-rows with a small track-pitch. Successive revolutions of the meta-spiral are separated by a narrow guard band. For high storage densities, such a system results in severe 2-D inter-symbol

  14. 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.

  15. Bitlis Bibliophil Association and One-Book Project

    Directory of Open Access Journals (Sweden)

    Hakan Yücel

    2014-03-01

    Full Text Available The article deals with Bitlis Bibliophil Association and One-Book Project which was established in January of the current year by a group of volunteer including several professions such as students, librarians, sociologists, engineers, civil cervants, teachers, bankers, poets, jorunalists, accountants.

  16. 2015 Southwest Florida RCD30 4-Band 8 Bit Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These files contain imagery data collected with an RCD30 camera as 8-bit RGBN TIFF images. Imagery was required 1000m seaward of the land/water interface or to laser...

  17. Architecture of 32 bit CISC (Complex Instruction Set Computer) microprocessors

    International Nuclear Information System (INIS)

    Jove, T.M.; Ayguade, E.; Valero, M.

    1988-01-01

    In this paper we describe the main topics about the architecture of the best known 32-bit CISC microprocessors; i80386, MC68000 family, NS32000 series and Z80000. We focus on the high level languages support, operating system design facilities, memory management, techniques to speed up the overall performance and program debugging facilities. (Author)

  18. 2015 Florida Panhandle RCD30 4-Band 8 Bit Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These files contain imagery data collected with an RCD30 camera as 8-bit RGBN TIFF images. Imagery was required 1000m seaward of the land/water interface or to laser...

  19. Quantum measurement and entanglement of spin quantum bits in diamond

    NARCIS (Netherlands)

    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

  20. "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...

  1. BIT/External Test Figures of Merit and Demonstration Techniques

    Science.gov (United States)

    1979-12-01

    111111 II * 0 IJ! E ii 6 A L 5.2.3 BIT caaiij.-The built-ln~tost I81T) capability $hall be Incorporated as required by the contrato assure...ETE physical characteristics arc straight forward and require no unique methodology for analysis or demonstration. 24 iU, VI T 3.2 DEFINITION OF

  2. Presettable up-down CAMAC counter for 24 bit

    International Nuclear Information System (INIS)

    Kuhn, K.; Meyer, U.; Weidhase, F.

    1976-01-01

    A module containing a presettable binary up-down CAMAC counter for 24 bit is described. The use of dataway is discussed. As an example for application in nuclear physics, control of beam position by the up-down counter is illustrated

  3. Factoring estimates for a 1024-bit RSA modulus

    NARCIS (Netherlands)

    Lenstra, A.K.; Tromer, E.; Shamir, A.; Kortsmit, W.J.P.M.; Dodson, B.; Hughes, J.; Leyland, P.; Laih, Chi Sung

    2003-01-01

    We estimate the yield of the number field sieve factoring algorithm when applied to the 1024-bit composite integer RSA-1024 and the parameters as proposed in the draft version [17] of the TWIRL hardware factoring device [18]. We present the details behind the resulting improved parameter choices

  4. BitTorrent's dilemma: Enhancing reciprocity or reducing inequity

    NARCIS (Netherlands)

    Jia, A.L.; D'Acunto, L.; Meulpolder, M.; Pouwelse, J.A.; Epema, D.H.J.

    2011-01-01

    Enhancing reciprocity has been one of the primary motivations for the design of incentive policies in BitTorrent-like P2P systems. Reciprocity implies that peers need to contribute their bandwidth to other peers if they want to receive bandwidth in return. However, the over-provisioning that

  5. Radiation hardened COTS-based 32-bit microprocessor

    International Nuclear Information System (INIS)

    Haddad, N.; Brown, R.; Cronauer, T.; Phan, H.

    1999-01-01

    A high performance radiation hardened 32-bit RISC microprocessor based upon a commercial single chip CPU has been developed. This paper presents the features of radiation hardened microprocessor, the methods used to radiation harden this device, the results of radiation testing, and shows that the RAD6000 is well-suited for the vast majority of space applications. (authors)

  6. 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.

  7. Designing the optimal bit: balancing energetic cost, speed and reliability.

    Science.gov (United States)

    Deshpande, Abhishek; Gopalkrishnan, Manoj; Ouldridge, Thomas E; Jones, Nick S

    2017-08-01

    We consider the challenge of operating a reliable bit that can be rapidly erased. We find that both erasing and reliability times are non-monotonic in the underlying friction, leading to a trade-off between erasing speed and bit reliability. Fast erasure is possible at the expense of low reliability at moderate friction, and high reliability comes at the expense of slow erasure in the underdamped and overdamped limits. Within a given class of bit parameters and control strategies, we define 'optimal' designs of bits that meet the desired reliability and erasing time requirements with the lowest operational work cost. We find that optimal designs always saturate the bound on the erasing time requirement, but can exceed the required reliability time if critically damped. The non-trivial geometry of the reliability and erasing time scales allows us to exclude large regions of parameter space as suboptimal. We find that optimal designs are either critically damped or close to critical damping under the erasing procedure.

  8. 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...

  9. The floating knee: epidemiology, prognostic indicators & outcome following surgical management

    OpenAIRE

    Yesupalan Rajam S; Rethnam Ulfin; Nair Rajagopalan

    2007-01-01

    Abstract Background Floating Knee injuries are complex injuries. The type of fractures, soft tissue and associated injuries make this a challenging problem to manage. We present the outcome of these injuries after surgical management. Methods 29 patients with floating knee injuries were managed over a 3 year period. This was a prospective study were both fractures of the floating knee injury were surgically fixed using different modalities. The associated injuries were managed appropriately. ...

  10. Integrated use of spatial and semantic relationships for extracting road networks from floating car data

    Science.gov (United States)

    Li, Jun; Qin, Qiming; Xie, Chao; Zhao, Yue

    2012-10-01

    The update frequency of digital road maps influences the quality of road-dependent services. However, digital road maps surveyed by probe vehicles or extracted from remotely sensed images still have a long updating circle and their cost remain high. With GPS technology and wireless communication technology maturing and their cost decreasing, floating car technology has been used in traffic monitoring and management, and the dynamic positioning data from floating cars become a new data source for updating road maps. In this paper, we aim to update digital road maps using the floating car data from China's National Commercial Vehicle Monitoring Platform, and present an incremental road network extraction method suitable for the platform's GPS data whose sampling frequency is low and which cover a large area. Based on both spatial and semantic relationships between a trajectory point and its associated road segment, the method classifies each trajectory point, and then merges every trajectory point into the candidate road network through the adding or modifying process according to its type. The road network is gradually updated until all trajectories have been processed. Finally, this method is applied in the updating process of major roads in North China and the experimental results reveal that it can accurately derive geometric information of roads under various scenes. This paper provides a highly-efficient, low-cost approach to update digital road maps.

  11. Functional Verification of Enhanced RISC Processor

    OpenAIRE

    SHANKER NILANGI; SOWMYA L

    2013-01-01

    This paper presents design and verification of a 32-bit enhanced RISC processor core having floating point computations integrated within the core, has been designed to reduce the cost and complexity. The designed 3 stage pipelined 32-bit RISC processor is based on the ARM7 processor architecture with single precision floating point multiplier, floating point adder/subtractor for floating point operations and 32 x 32 booths multiplier added to the integer core of ARM7. The binary representati...

  12. 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.

  13. Stress analysis and mitigation measures for floating pipeline

    Science.gov (United States)

    Wenpeng, Guo; Yuqing, Liu; Chao, Li

    2017-03-01

    Pipeline-floating is a kind of accident with contingency and uncertainty associated to natural gas pipeline occurring during rainy season, which is significantly harmful to the safety of pipeline. Treatment measures against pipeline floating accident are summarized in this paper on the basis of practical project cases. Stress states of pipeline upon floating are analyzed by means of Finite Element Calculation method. The effectiveness of prevention ways and subsequent mitigation measures upon pipeline-floating are verified for giving guidance to the mitigation of such accidents.

  14. Wave energy, lever operated pivoting float LOPF study

    Energy Technology Data Exchange (ETDEWEB)

    Margheritini, L.

    2012-11-01

    The fully instrumented Resen Waves Lever Operated Pivoting Float LOPF wave energy buoy model has gone through the first stage of testing in regular waves in scale 1:25 of the North Sea wave conditions, in the 3D deep wave basin at the Hydraulic and Coastal Engineering Laboratory of Aalborg University in Denmark. The model size was 60cm W x 90cm L x 21cm H. The 60 cm width pointed towards the wave front. The LOPF buoy is characterized by a simple mechanical design with few moving parts and direct electrical output and it is taut moored to the sea bed, so all forces are referenced to the seabed for maximum energy output in regular as well as irregular waves. During storms the buoy pivots and streamlines itself to minimize loads on the mooring line. A conservative estimate shows that a full scale system for North Sea conditions has a float size width of 15 m that will, with 60% generator efficiency, produce 610 MWh/y (609.497 kWh/y) with an average power output of 69.6 kW, which requires a generator capacity of 700 kW. It is expected the generator efficiency can be increased to 90% in the future. More specific calculations (from EnergiNet) show that with one generator of 695 kW the expected power production is 585 MWh/y; with a generator of 250 kW and 100 kW, the expected power production is 481 MWh/y and 182 MWh/y respectively. In addition there are several areas for future improvements for increased power production. (Author)

  15. Modeling and simulation of floating gate nanocrystal FET devices and circuits

    Science.gov (United States)

    Hasaneen, El-Sayed A. M.

    The nonvolatile memory market has been growing very fast during the last decade, especially for mobile communication systems. The Semiconductor Industry Association International Technology Roadmap for Semiconductors states that the difficult challenge for nonvolatile semiconductor memories is to achieve reliable, low power, low voltage performance and high-speed write/erase. This can be achieved by aggressive scaling of the nonvolatile memory cells. Unfortunately, scaling down of conventional nonvolatile memory will further degrade the retention time due to the charge loss between the floating gate and drain/source contacts and substrate which makes conventional nonvolatile memory unattractive. Using nanocrystals as charge storage sites reduces dramatically the charge leakage through oxide defects and drain/source contacts. Floating gate nanocrystal nonvolatile memory, FG-NCNVM, is a candidate for future memory because it is advantageous in terms of high-speed write/erase, small size, good scalability, low-voltage, low-power applications, and the capability to store multiple bits per cell. Many studies regarding FG-NCNVMs have been published. Most of them have dealt with fabrication improvements of the devices and device characterizations. Due to the promising FG-NCNVM applications in integrated circuits, there is a need for circuit a simulation model to simulate the electrical characteristics of the floating gate devices. In this thesis, a FG-NCNVM circuit simulation model has been proposed. It is based on the SPICE BSIM simulation model. This model simulates the cell behavior during normal operation. Model validation results have been presented. The SPICE model shows good agreement with experimental results. Current-voltage characteristics, transconductance and unity gain frequency (fT) have been studied showing the effect of the threshold voltage shift (DeltaVth) due to nanocrystal charge on the device characteristics. The threshold voltage shift due to

  16. Advantages of floating covers with LLDPE Liners

    International Nuclear Information System (INIS)

    Munoz Gomez, J. M.

    2014-01-01

    Using floating covers in irrigation pounds and waste dam gives many advantages. It is a very interesting investment for those place with a high evaporation ratio. this is an easy system which improves several aspects in irrigation or drinkable water reservoirs, mainly it saves water and it saves clean-works (time and cost). It is also used in waste dam to deodorization. Time ago this application was developed with PVC liners and TPO liners, now the innovation is LLDPE liners which improve mechanical properties, durability and an easier installation. This paper develops the state of art of this design technology, and the back ground of our experience. (Author)

  17. Horizontal, floating, plastic hose oil skimmer

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    A horizontal, floating, plastic hose oil skimmer operates at -20/sup 0/ to +100/sup 0/C as a moving belt driven by a motor at 0.7 kw at 1400 rpm to pick up oil by adhesion from a surface such as that of used cooling water or cutting oil for subsequent stripping and collection by gravity flow. Two models provide collection rates of 10-45 l./hr for diesel oil, 35-115 l./hr for hydraulic oil, and 170-455 l./hr for gear oils and heavy heating oils.

  18. Experiments in a floating water bridge

    Science.gov (United States)

    Woisetschläger, Jakob; Gatterer, Karl; Fuchs, Elmar C.

    2010-01-01

    In a high-voltage direct-current experiment, a watery connection formed between two beakers filled with deionized water, giving the impression of a `floating water bridge'. Having a few millimeters diameter and up to 2.5 cm length, this watery connection reveals a number of interesting phenomena currently discussed in water science. Focusing on optical measurement techniques, the flow through the bridge was visualized and data were recorded such as flow velocity and directions, heat production, density fluctuations, pH values, drag force and mass transfer. To provide a better understanding of the basic phenomena involved the discussion references related literature.

  19. Dynamics of the floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Gatterer, Karl; Holler, Gert; Woisetschlaeger, Jakob

    2008-01-01

    When high voltage is applied to distilled water filled into two beakers close to each other, a water connection forms spontaneously, giving the impression of a floating water bridge (Fuchs et al 2007 J. Phys. D: Appl. Phys. 40 6112-4). This phenomenon is of special interest, since it comprises a number of phenomena currently tackled in modern water science. The build-up mechanism, the chemical properties and the dynamics of this bridge as well as related additional phenomena are presented and discussed

  20. The floating desalination complex GEYSER-1

    International Nuclear Information System (INIS)

    Vorobyov, V.M.

    1997-01-01

    A conventional floating desalination complex, GEYSER-1, is presented which is capable of producing 40,000 cubic meters per day (m 3 /d) of fresh water from brackish water or seawater. The complex includes a water intake system, a preliminary water preparation system, a high-pressure pump house and a power installation based on diesel or a gas turbines with service equipment. GEYSER-1 can be transported to the place of operation either by a heavy lift ship or by towing. (author)

  1. Floating Foundations for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Andersen, Morten Thøtt

    The concept of harnessing the power of the wind dates all the way back to the first ships traversing the seas. Later, windmills enabled the use of wind power for industrial purposes. Since then, technology has allowed the production of clean renewable energy through the use of wind turbines....... These turbines have traditionally been placed on land, but several factors have urged a move to offshore locations. Now the boundaries are being pushed into deeper and deeper waters, where the idea of floating offshore wind turbines has emerged. In less than a decade, these have gone from scattered small...

  2. Floating retained root lesion mimicking apical periodontitis.

    Science.gov (United States)

    Chung, Ming-Pang; Chen, Chih-Ping; Shieh, Yi-Shing

    2009-10-01

    A case of a retained root tip simulating apical periodontitis on radiographic examination is described. The retained root tip, originating from the left lower first molar, floated under the left lower second premolar apical region mimicking apical periodontitis. It appeared as an ill-defined periapical radiolucency containing a smaller radiodense mass on radiograph. The differential diagnosis included focal sclerosing osteomyelitis (condensing osteitis) and ossifying fibroma. Upon exicisional biopsy, a retained root associated with granulation tissue was found. After 1-year follow-up, the patient was asymptomatic and the periradicular lesion was healing. Meanwhile, the associated tooth showed a normal response to stimulation testing.

  3. Near-Shore Floating Wave Energy Converters

    DEFF Research Database (Denmark)

    Ruol, Piero; Zanuttigh, Barbara; Martinelli, Luca

    2011-01-01

    and transmission characteristics are approximated to functions of wave height, period and obliquity. Their order of magnitude are 20% and 80%, respectively. It is imagined that an array of DEXA is deployed in front of Marina di Ravenna beach (IT), a highly touristic site of the Adriatic Coast. Based on the CERC......Aim of this note is to analyse the possible application of a Wave Energy Converter (WEC) as a combined tool to protect the coast and harvest energy. Physical model tests are used to evaluate wave transmission past a near-shore floating WEC of the wave activated body type, named DEXA. Efficiency...

  4. Stability analysis of the Gyroscopic Power Take-Off wave energy point absorber

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Zhang, Zili; Kramer, Morten Mejlhede

    2015-01-01

    The Gyroscopic Power Take-Off (GyroPTO) wave energy point absorber consists of a float rigidly connected to a lever. The operational principle is somewhat similar to that of the so-called gyroscopic hand wrist exercisers, where the rotation of the float is brought forward by the rotational particle...

  5. Animal Diet Formulation with Floating Price

    Directory of Open Access Journals (Sweden)

    S.H Nasseri

    2016-12-01

    Full Text Available In the process of milk production, the highest cost relates to animal feed. Based on reports provided by the experts, around seventy percent of dairy livestock costs included feed costs. In order to minimize the total price of livestock feed, according to the limits of feed sources in each region or season, and also the transportation and maintenance costs and ultimately milk price reduction, optimization of the livestock nutrition program is an essential issue. Because of the uncertainty and lack of precision in the optimal food ration done with existing methods based on linear programming, there is a need to use appropriate methods to meet this purpose. Therefore, in this study formulation of completely mixed nutrient diets of dairy cows is done by using a fuzzy linear programming in early lactation. Application of fuzzy optimization method and floating price make it possible to formulate and change the completely mixed diets with adequate safety margins. Therefore, applications of fuzzy methods in feed rations of dairy cattle are recommended to optimize the diets. Obviously, it would be useful to design suitable software, which provides the possibility of using floating prices to set feed rations by the use of fuzzy optimization method.

  6. Water-Pressure Distribution on Seaplane Float

    Science.gov (United States)

    Thompson, F L

    1929-01-01

    The investigation presented in this report was conducted for the purpose of determining the distribution and magnitude of water pressures likely to be experienced on seaplane hulls in service. It consisted of the development and construction of apparatus for recording water pressures lasting one one-hundredth second or longer and of flight tests to determine the water pressures on a UO-1 seaplane float under various conditions of taxiing, taking off, and landing. The apparatus developed was found to operate with satisfactory accuracy and is suitable for flight tests on other seaplanes. The tests on the UO-1 showed that maximum pressures of about 6.5 pounds per square inch occur at the step for the full width of the float bottom. Proceeding forward from the step the maximum pressures decrease in magnitude uniformly toward the bow, and the region of highest pressures narrows toward the keel. Immediately abaft the step the maximum pressures are very small, but increase in magnitude toward the stern and there once reached a value of about 5 pounds per square inch. (author)

  7. Feasibility study on floating nuclear power station

    International Nuclear Information System (INIS)

    Kajima, Ryoichi

    1987-01-01

    It is stipulated that nuclear power plants are to be built on solid rock bases on land in Japan. However, there are a limited number of appropriate siting grounds. The Central Research Institute of Electric Power Industry has engaged since 1981 in the studies on the construction technology of power plants, aiming at establishing new siting technology to expand the possible siting areas for nuclear power plants. Underground siting is regarded as a proven technology due to the experience in underground hydroelectric power plants. The technology of siting on quaternary ground is now at the stage of verification. In this report, the outline of floating type offshore/inshore siting technology is introduced, which is considered to be feasible in view of the technical and economical aspects. Three fixed structure types were selected, of which the foundations are fixed to seabed, plant superstructures are above sea surface, and which are floating type. Aiming at ensuring the aseismatic stability of the plant foundations, the construction technology is studied, and the structural concept omitting buoyancy is possible. The most practical water depth is not more than 20 m. The overall plant design, earthquake isolation effect and breakwater are described. (Kako, I.)

  8. Floating / Travelling Gardens of (Postcolonial Time

    Directory of Open Access Journals (Sweden)

    Carmen Concilio

    2017-11-01

    Full Text Available This essay on travelling gardens of (postcolonial time opens with two iconic images of floating gardens in contemporary postcolonial literature: Will Phantom’s bio-garbage rafter, which saves him in the midst of a cyclone in Carpentaria (2008, by the Aboriginal author Alexis Wright, and Pi’s carnivore island-organism in Life of Pi (2001, which cannot save him from his shipwreck, by Canadian writer Yan Martel. These floating, hybrid gardens of the Anthropocene precede the real travelling gardens of both Michael Ondaatje’s The Cat’s Table (2011 and Amitav Ghosh’s Ibis Trilogy (2008-2015, two authors who both indirectly and directly tell the story of botanical gardens in Asia, and of plant and seed smuggling and transplantation (“displacement” also hinting at their historical and economic colonial implications. For, after all, botanical gardens imply a very specific version of care, Cura (Robert Pogue Harrison 2009, while embodying a precise, imperial scientific and economic project (Brockway 2002; Johnson 2011.

  9. 14 CFR 136.11 - Helicopter floats for over water.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Helicopter floats for over water. 136.11... TOURS AND NATIONAL PARKS AIR TOUR MANAGEMENT National Air Tour Safety Standards § 136.11 Helicopter floats for over water. (a) A helicopter used in commercial air tours over water beyond the shoreline must...

  10. Production of floating pellets using appropriate methods | Suleiman ...

    African Journals Online (AJOL)

    The study investigated into the use of floating materials like candle wax, yeast and baking powder to achieve pellet buoyancy. Ten diets were formulated with incorporation of floating agents; Diet I-YBCT- (yeast-baking powder in cold water -toasted), Diet II-YBCU- (yeast-baking powder in cold water -untoasted) Diet III ...

  11. Design and Evaluation of an Oral Floating Matrix Tablet of ...

    African Journals Online (AJOL)

    Purpose: To develop floating matrix tablets of salbutamol sulphate using ethyl cellulose and acrycoat S-100 as polymers, and sodium bicarbonate, citric acid and tartaric acid as gas generating agents. Methods: Twenty four formulations were prepared and segregated into four major categories, A to D. The floating tablets ...

  12. Response estimation for a floating bridge using acceleration output only

    NARCIS (Netherlands)

    Petersen, Øyvind Wiig; Øiseth, Ole; Nord, Torodd Skjerve; Lourens, E.; Sas, P.; Moens, D.; van de Walle, A.

    2016-01-01

    The Norwegian Public Roads Administration is reviewing the possibility of using floating bridges as fjord crossings. The dynamic behaviour of very long floating bridges with novel designs are prone to uncertainties. Studying the dynamic behaviour of existing bridges is valuable for understanding

  13. Development and evaluation of floating microspheres of curcumin in ...

    African Journals Online (AJOL)

    Purpose: To prepare and evaluate floating microspheres of curcumin for prolonged gastric residence and to study their effect on alloxan-induced diabetic rats. Methods: Floating microsphere were prepared by emulsion-solvent diffusion method, using hydroxylpropyl methylcellulose, chitosan and Eudragit S 100 polymer in ...

  14. Development and Evaluation of Floating Microspheres of Curcumin ...

    African Journals Online (AJOL)

    Purpose: To prepare and evaluate floating microspheres of curcumin for prolonged gastric residence time and increased drug bioavailability. Methods: Floating microsphere were prepared by emulsion solvent diffusion method, using hydroxylpropyl methylcellulose (HPMC), ethyl cellulose (EC), Eudragit S 100 polymer in ...

  15. Herbal carrier-based floating microparticles of diltiazem ...

    African Journals Online (AJOL)

    Purpose: To formulate and characterize a gastroretentive floating drug delivery system for diltiazem hydrochloride using psyllium husk and sodium alginate as natural herbal carriers to improve the therapeutic effect of the drug in cardiac patients. Methods: Floating microparticles containing diltiazem hydrochloride were ...

  16. Floating Solar Photovoltaics Gaining Ground | State, Local, and Tribal

    Science.gov (United States)

    flotovoltaics (a trademarked term) or floating solar, represent an emerging application in which PV panels are , including efficiency gains (due to water cooling the panels), reductions in unwanted algae growth, slower 994 panels floating on 130 foam-filled pontoons atop the winery's irrigation pond and an additional

  17. Modular trigger processing The GCT muon and quiet bit system

    CERN Document Server

    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.

  18. Finger Vein Recognition Based on a Personalized Best Bit Map

    Science.gov (United States)

    Yang, Gongping; Xi, Xiaoming; Yin, Yilong

    2012-01-01

    Finger vein patterns have recently been recognized as an effective biometric identifier. In this paper, we propose a finger vein recognition method based on a personalized best bit map (PBBM). Our method is rooted in a local binary pattern based method and then inclined to use the best bits only for matching. We first present the concept of PBBM and the generating algorithm. Then we propose the finger vein recognition framework, which consists of preprocessing, feature extraction, and matching. Finally, we design extensive experiments to evaluate the effectiveness of our proposal. Experimental results show that PBBM achieves not only better performance, but also high robustness and reliability. In addition, PBBM can be used as a general framework for binary pattern based recognition. PMID:22438735

  19. Wear Detection of Drill Bit by Image-based Technique

    Science.gov (United States)

    Sukeri, Maziyah; Zulhilmi Paiz Ismadi, Mohd; Rahim Othman, Abdul; Kamaruddin, Shahrul

    2018-03-01

    Image processing for computer vision function plays an essential aspect in the manufacturing industries for the tool condition monitoring. This study proposes a dependable direct measurement method to measure the tool wear using image-based analysis. Segmentation and thresholding technique were used as the means to filter and convert the colour image to binary datasets. Then, the edge detection method was applied to characterize the edge of the drill bit. By using cross-correlation method, the edges of original and worn drill bits were correlated to each other. Cross-correlation graphs were able to detect the difference of the worn edge despite small difference between the graphs. Future development will focus on quantifying the worn profile as well as enhancing the sensitivity of the technique.

  20. The 40 Gbps cascaded bit-interleaving PON

    Science.gov (United States)

    Vyncke, A.; Torfs, G.; Van Praet, C.; Verbeke, M.; Duque, A.; Suvakovic, D.; Chow, H. K.; Yin, X.

    2015-12-01

    In this paper, a 40 Gbps cascaded bit-interleaving passive optical network (CBI-PON) is proposed to achieve power reduction in the network. The massive number of devices in the access network makes that power consumption reduction in this part of the network has a major impact on the total network power consumption. Starting from the proven BiPON technology, an extension to this concept is proposed to introduce multiple levels of bit-interleaving. The paper discusses the CBI protocol in detail, as well as an ASIC implementation of the required custom CBI Repeater and End-ONT. From the measurements of this first 40 Gbps ASIC prototype, power consumption reduction estimates are presented.

  1. Very low bit rate voice for packetized mobile applications

    International Nuclear Information System (INIS)

    Knittle, C.D.; Malone, K.T.

    1991-01-01

    This paper reports that transmitting digital voice via packetized mobile communications systems that employ relatively short packet lengths and narrow bandwidths often necessitates very low bit rate coding of the voice data. Sandia National Laboratories is currently developing an efficient voice coding system operating at 800 bits per second (bps). The coding scheme is a modified version of the 2400 bps NSA LPC-10e standard. The most significant modification to the LPC-10e scheme is the vector quantization of the line spectrum frequencies associated with the synthesis filters. An outline of a hardware implementation for the 800 bps coder is presented. The speech quality of the coder is generally good, although speaker recognition is not possible. Further research is being conducted to reduce the memory requirements and complexity of the vector quantizer, and to increase the quality of the reconstructed speech. This work may be of use dealing with nuclear materials

  2. 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...... in accordance with psycho-acoustical principles. Masker frequencies of 500 Hz, 1 kHz, and 2 kHz have been investigated, and the masking of pure tone probes has been determined in the first four 1/3 octaves above the masker. Modulation frequencies between 6 and 20 Hz were used with a modulation depth of 0...

  3. b.i.t. Bremerhaven: Thin Clients entlasten Schulen

    Science.gov (United States)

    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.

  4. Analysis of Button Bit Wear and Performance of Down-The-Hole ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... revealed that wear of rock drill bit is influenced by rock properties. ... equivalent quartz content and silica content are dominant rock properties affecting wear rate of bit button of DTH drill. ..... Cutting, Drilling and Blasting: Rock.

  5. 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....

  6. Industrial automation in floating production vessels for deep water oil and gas fields

    International Nuclear Information System (INIS)

    de Garcia, A.L.; Ferrante, A.J.

    1990-01-01

    The process supervision in offshore platforms was performed in the past through the use of local pneumatic instrumentation, based on relays, semi-graphic panels and button operated control panels. Considering the advanced technology used in the new floating production projects for deep water, it became mandatory to develop supervision systems capable of integrating different control panels, increasing the level of monitorization and reducing the number of operators and control rooms. From the point of view of field integration, a standardized architecture makes the communication between different production platforms and the regional headquarters, where all the equipment and support infrastructure for the computerized network is installed, possible. This test paper describes the characteristics of the initial systems, the main problems observed, the studies performed and the results obtained in relation to the design and implementation of computational systems with open architecture for automation of process control in floating production systems for deep water in Brazil

  7. VCSEL Scaling, Laser Integration on Silicon, and Bit Energy

    Science.gov (United States)

    2017-03-01

    especially the laser. Highly compact directly modulated lasers ( DMLs ) have been researched to meet this goal. The most favored technology will likely be...question of which achieves lower bit energy, a DML or a continuous-wave (CW) laser coupled to an integrated modulator. Transceiver suppliers are also...development that can utilize high efficiency DMLs that reach very high modulation speed. Oxide-VCSELs [1] do not yet take full advantage of the

  8. Purely Functional Compressed Bit Vectors with Applications and Implementations

    OpenAIRE

    Kaasinen, Joel

    2011-01-01

    The study of compressed data structures strives to represent information on a computer concisely — using as little space as possible. Compressed bit vectors are the simplest compressed data structure. They are used as a basis for more complex data structures with applications in, for example, computational biology. Functional programming is a programming paradigm that represents computation using functions without side-effects (such as mutation). Data structures that are representable in...

  9. Parallel-Bit Stream for Securing Iris Recognition

    OpenAIRE

    Elsayed Mostafa; Maher Mansour; Heba Saad

    2012-01-01

    Biometrics-based authentication schemes have usability advantages over traditional password-based authentication schemes. However, biometrics raises several privacy concerns, it has disadvantages comparing to traditional password in which it is not secured and non revocable. In this paper, we propose a fast method for securing revocable iris template using parallel-bit stream watermarking to overcome these problems. Experimental results prove that the proposed method has low computation time ...

  10. A Note on 5-bit Quadratic Permutations’ Classification

    OpenAIRE

    Božilov, Dušan; Bilgin, Begül; Sahin, Hacı Ali

    2017-01-01

    Classification of vectorial Boolean functions up to affine equivalence is used widely to analyze various cryptographic and implementation properties of symmetric-key algorithms. We show that there exist 75 affine equivalence classes of 5-bit quadratic permutations. Furthermore, we explore important cryptographic properties of these classes, such as linear and differential properties and degrees of their inverses, together with multiplicative complexity and existence of uniform threshold reali...

  11. 16-Bit RISC Processor Design for Convolution Application

    OpenAIRE

    Anand Nandakumar Shardul

    2013-01-01

    In this project, we propose a 16-bit non-pipelined RISC processor, which is used for signal processing applications. The processor consists of the blocks, namely, program counter, clock control unit, ALU, IDU and registers. Advantageous architectural modifications have been made in the incremented circuit used in program counter and carry select adder unit of the ALU in the RISC CPU core. Furthermore, a high speed and low power modified modifies multiplier has been designed and introduced in ...

  12. ASIC For Complex Fixed-Point Arithmetic

    Science.gov (United States)

    Petilli, Stephen G.; Grimm, Michael J.; Olson, Erlend M.

    1995-01-01

    Application-specific integrated circuit (ASIC) performs 24-bit, fixed-point arithmetic operations on arrays of complex-valued input data. High-performance, wide-band arithmetic logic unit (ALU) designed for use in computing fast Fourier transforms (FFTs) and for performing ditigal filtering functions. Other applications include general computations involved in analysis of spectra and digital signal processing.

  13. A novel grounded to floating admittance converter with electronic control

    Science.gov (United States)

    Prasad, Dinesh; Ahmad, Javed; Srivastava, Mayank

    2018-01-01

    This article suggests a new grounded to floating admittance convertor employing only two voltage differencing transconductance amplifiers (VDTAs). The proposed circuit can convert any arbitrary grounded admittance into floating admittance with electronically controllable scaling factor. The presented converter enjoys the following beneficial: (1) no requirement of any additional passive element (2) scaling factor can be tuned electronically through bias currents of VDTAs (3) no matching constraint required (4) low values of active/passive sensitivity indexes and (5) excellent non ideal behavior that indicates no deviation in circuit behavior even under non ideal environment. Application of the proposed configuration in realization of floating resistor and floating capacitor has been presented and the workability of these floating elements has been confirmed by active filter design examples. SPICE simulations have been performed to demonstrate the performance of the proposed circuits.

  14. Digital Signal Processing For Low Bit Rate TV Image Codecs

    Science.gov (United States)

    Rao, K. R.

    1987-06-01

    In view of the 56 KBPS digital switched network services and the ISDN, low bit rate codecs for providing real time full motion color video are under various stages of development. Some companies have already brought the codecs into the market. They are being used by industry and some Federal Agencies for video teleconferencing. In general, these codecs have various features such as multiplexing audio and data, high resolution graphics, encryption, error detection and correction, self diagnostics, freezeframe, split video, text overlay etc. To transmit the original color video on a 56 KBPS network requires bit rate reduction of the order of 1400:1. Such a large scale bandwidth compression can be realized only by implementing a number of sophisticated,digital signal processing techniques. This paper provides an overview of such techniques and outlines the newer concepts that are being investigated. Before resorting to the data compression techniques, various preprocessing operations such as noise filtering, composite-component transformation and horizontal and vertical blanking interval removal are to be implemented. Invariably spatio-temporal subsampling is achieved by appropriate filtering. Transform and/or prediction coupled with motion estimation and strengthened by adaptive features are some of the tools in the arsenal of the data reduction methods. Other essential blocks in the system are quantizer, bit allocation, buffer, multiplexer, channel coding etc.

  15. On the Lorentz invariance of bit-string geometry

    International Nuclear Information System (INIS)

    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 pointclose quotes and three integer distances to this open-quotes pointclose 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)

  16. High performance 14-bit pipelined redundant signed digit ADC

    International Nuclear Information System (INIS)

    Narula, Swina; Pandey, Sujata

    2016-01-01

    A novel architecture of a pipelined redundant-signed-digit analog to digital converter (RSD-ADC) is presented featuring a high signal to noise ratio (SNR), spurious free dynamic range (SFDR) and signal to noise plus distortion (SNDR) with efficient background correction logic. The proposed ADC architecture shows high accuracy with a high speed circuit and efficient utilization of the hardware. This paper demonstrates the functionality of the digital correction logic of 14-bit pipelined ADC at each 1.5 bit/stage. This prototype of ADC architecture accounts for capacitor mismatch, comparator offset and finite Op-Amp gain error in the MDAC (residue amplification circuit) stages. With the proposed architecture of ADC, SNDR obtained is 85.89 dB, SNR is 85.9 dB and SFDR obtained is 102.8 dB at the sample rate of 100 MHz. This novel architecture of digital correction logic is transparent to the overall system, which is demonstrated by using 14-bit pipelined ADC. After a latency of 14 clocks, digital output will be available at every clock pulse. To describe the circuit behavior of the ADC, VHDL and MATLAB programs are used. The proposed architecture is also capable of reducing the digital hardware. Silicon area is also the complexity of the design. (paper)

  17. 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.

  18. Application of morphological bit planes in retinal blood vessel extraction.

    Science.gov (United States)

    Fraz, M M; Basit, A; Barman, S A

    2013-04-01

    The appearance of the retinal blood vessels is an important diagnostic indicator of various clinical disorders of the eye and the body. Retinal blood vessels have been shown to provide evidence in terms of change in diameter, branching angles, or tortuosity, as a result of ophthalmic disease. This paper reports the development for an automated method for segmentation of blood vessels in retinal images. A unique combination of methods for retinal blood vessel skeleton detection and multidirectional morphological bit plane slicing is presented to extract the blood vessels from the color retinal images. The skeleton of main vessels is extracted by the application of directional differential operators and then evaluation of combination of derivative signs and average derivative values. Mathematical morphology has been materialized as a proficient technique for quantifying the retinal vasculature in ocular fundus images. A multidirectional top-hat operator with rotating structuring elements is used to emphasize the vessels in a particular direction, and information is extracted using bit plane slicing. An iterative region growing method is applied to integrate the main skeleton and the images resulting from bit plane slicing of vessel direction-dependent morphological filters. The approach is tested on two publicly available databases DRIVE and STARE. Average accuracy achieved by the proposed method is 0.9423 for both the databases with significant values of sensitivity and specificity also; the algorithm outperforms the second human observer in terms of precision of segmented vessel tree.

  19. 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.

  20. SOLAR TRACKER CERDAS DAN MURAH BERBASIS MIKROKONTROLER 8 BIT ATMega8535

    OpenAIRE

    I Wayan Sutaya; Ketut Udy Ariawan

    2016-01-01

    prototipe produk solar tracker cerdas berbasis mikrokontroler AVR 8 bit. Solar tracker ini memasukkan filter digital IIR (Infinite Impulse Response) pada bagian program. Memprogram filter ini membutuhkan perkalian 32 bit sedangkan prosesor yang tersedia pada mikrokontroler yang dipakai adalah 8 bit. Proses perkalian ini hanya bisa dilakukan pada mikrokontroler 8 bit dengan menggunakan bahasa assembly yang merupakan bahasa level hardware. Solar tracker cerdas yang menggunakan mikrokontroler 8 ...

  1. Effects of plastic bits on the condition and behaviour of captive-reared pheasants.

    Science.gov (United States)

    Butler, D A; Davis, C

    2010-03-27

    Between 2005 and 2007, data were collected from game farms across England and Wales to examine the effects of the use of bits on the physiological condition and behaviour of pheasants. On each site, two pheasant pens kept in the same conditions were randomly allocated to either use bits or not. The behaviour and physiological conditions of pheasants in each treatment pen were assessed on the day of bitting and weekly thereafter until release. Detailed records of feed usage, medications and mortality were also kept. Bits halved the number of acts of bird-on-bird pecking, but they doubled the incidence of headshaking and scratching. Bits caused nostril inflammation and bill deformities in some birds, particularly after seven weeks of age. In all weeks after bitting, feather condition was poorer in non-bitted pheasants than in those fitted with bits. Less than 3 per cent of bitted birds had damaged skin, but in the non-bitted pens this figure increased over time to 23 per cent four weeks later. Feed use and mortality did not differ between bitted and non-bitted birds.

  2. Surgical drill system and surgical drill bit to be used therein

    NARCIS (Netherlands)

    Margallo Balbas, E.; Wieringa, P.A.; French, P.J.; Lee, R.A.; Breedveld, P.

    2007-01-01

    Surgical drill system comprising a mechanical drill bit and means for imaging the vicinity of the drill bit tip, said means comprising: at least one optical fiber having a distal end and a proximal end, said distal end being located adjacent said drill bit tip, an optical processing unit, said

  3. Analysis of Switched-Rigid Floating Oscillator

    Directory of Open Access Journals (Sweden)

    Prabhakar R. Marur

    2009-01-01

    Full Text Available In explicit finite element simulations, a technique called deformable-to-rigid (D2R switching is used routinely to reduce the computation time. Using the D2R option, the deformable parts in the model can be switched to rigid and reverted back to deformable when needed during the analysis. The time of activation of D2R however influences the overall dynamics of the system being analyzed. In this paper, a theoretical basis for the selection of time of rigid switching based on system energy is established. A floating oscillator problem is investigated for this purpose and closed-form analytical expressions are derived for different phases in rigid switching. The analytical expressions are validated by comparing the theoretical results with numerical computations.

  4. Preliminary results from NOAMP deep drifting floats

    International Nuclear Information System (INIS)

    Ollitrault, M.

    1989-01-01

    This paper is a very brief and preliminary outline of first results obtained with deep SOFAR floats in the NOAMP area. The work is now going toward more precise statistical estimations of mean and variable currents, together with better tracking to resolve submesoscales and estimate diffusivities due to mesoscale and smaller scale motions. However the preliminary results confirm that the NOAMP region (and surroundings) has a deep mesoscale eddy field that is considerably more energetic that the mean field (r.m.s. velocities are of order 5 cm s -1 ), although both values are diminished compared to the western basin. A data report containing trajectories and statistics is scheduled to be published by IFREMER in the near future. The project main task is to especially study the dispersion of radioactive substances

  5. Ionizing radiation effects on floating gates

    International Nuclear Information System (INIS)

    Cellere, G.; Paccagnella, A.; Visconti, A.; Bonanomi, M.

    2004-01-01

    Floating gate (FG) memories, and in particular Flash, are the dominant among modern nonvolatile memory technologies. Their performance under ionizing radiation was traditionally studied for the use in space, but has become of general interest in recent years. We are showing results on the charge loss from programmed FG arrays after 10 keV x-rays exposure. Exposure to ionizing radiation results in progressive discharge of the FG. More advanced devices, featuring smaller FG, are less sensitive to ionizing radiation that older ones. The reason is identified in the photoemission of electrons from FG, since at high doses it dominates over charge loss deriving from electron/hole pairs generation in the oxides

  6. Nuclear Security for Floating Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Skiba, James M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scherer, Carolynn P. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-10-13

    Recently there has been a lot of interest in small modular reactors. A specific type of these small modular reactors (SMR,) are marine based power plants called floating nuclear power plants (FNPP). These FNPPs are typically built by countries with extensive knowledge of nuclear energy, such as Russia, France, China and the US. These FNPPs are built in one country and then sent to countries in need of power and/or seawater desalination. Fifteen countries have expressed interest in acquiring such power stations. Some designs for such power stations are briefly summarized. Several different avenues for cooperation in FNPP technology are proposed, including IAEA nuclear security (i.e. safeguards), multilateral or bilateral agreements, and working with Russian design that incorporates nuclear safeguards for IAEA inspections in non-nuclear weapons states

  7. Sharing risk and reward - floating production contractorship

    International Nuclear Information System (INIS)

    Gisvold, K.M.

    1994-01-01

    The conference paper summarizes the contractual experience so far gained on Petrojarl 1 floating production system and the associated shuttling services on the Norwegian continental shelf. The paper attempts to draw some lines into the future with respect to development of the business format and the evolution of the relationship between the contractor and the various oil companies in question. Turnkey production services as well as transport and project services to the oil industry are provided. The scope of these services ranges from top of the sea bed wellhead to quayside at the refinery, and is based on ownership control of the employed vessels as well as complete manning of all services. 7 figs

  8. Present situation of floating nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, A [Central Research Inst. of Electric Power industry, Tokyo (Japan)

    1975-08-01

    The present situation of investigation and the future problems of floating nuclear power plants in Japan are examined, referring to those in USA. The committee report on a new power generation system in 1970 is quoted. In this report, the site conditions are supposed to be 5 km offshore, 100m water depth, 60 m/sec wind velocity, 10 m wave height, 200 m wave length, 12 seconds wave period 0.2 g earthquake acceleration, and 2.5 knots tide current. The semisubmersible hull of double construction 15 m under water is employed. A pair of 1,000,000 kW BWR reactors are utilized. A sea water desalting unit using bleed steam from turbines is installed. The solid radioactive wastes packed in drums are disposed in the sea. The design and cost estimation were made. The names of the organizations who have made investigation in this field, namely the Civil Engineering Society, the Sience and Technology Agency and other several centers, are reported. The Chubu Electric Power Company is forwarding its project. Referring to the investigations in USA, the project of Atlantic nuclear power station unit is described. A report of plant design has been submitted by O.P.S. to United States Atomic Energy Commission in 1973. The Coastal Area Facilities Act was instituted in New Jersey in 1973. Although the Atlantic nuclear power station has been postponed, it is the most feasible project. For the realization of a floating nuclear power plant in Japan, investigation must be started on the ground construction that can endure the construction of breakwater in water depth of 14 to 30 meter.

  9. Potential of water surface-floating microalgae for biodiesel production: Floating-biomass and lipid productivities.

    Science.gov (United States)

    Muto, Masaki; Nojima, Daisuke; Yue, Liang; Kanehara, Hideyuki; Naruse, Hideaki; Ujiro, Asuka; Yoshino, Tomoko; Matsunaga, Tadashi; Tanaka, Tsuyoshi

    2017-03-01

    Microalgae have been accepted as a promising feedstock for biodiesel production owing to their capability of converting solar energy into lipids through photosynthesis. However, the high capital and operating costs, and high energy consumption, are hampering commercialization of microalgal biodiesel. In this study, the surface-floating microalga, strain AVFF007 (tentatively identified as Botryosphaerella sudetica), which naturally forms a biofilm on surfaces, was characterized for use in biodiesel production. The biofilm could be conveniently harvested from the surface of the water by adsorbing onto a polyethylene film. The lipid productivity of strain AVFF007 was 46.3 mg/L/day, allowing direct comparison to lipid productivities of other microalgal species. The moisture content of the surface-floating biomass was 86.0 ± 1.2%, which was much lower than that of the biomass harvested using centrifugation. These results reveal the potential of this surface-floating microalgal species as a biodiesel producer, employing a novel biomass harvesting and dewatering strategy. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. WindWaveFloat (WWF): Final Scientific Report

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Alla; Roddier, Dominique; Banister, Kevin

    2012-03-30

    Principle Power Inc. and National Renewable Energy Lab (NREL) have completed a contract to assess the technical and economic feasibility of integrating wave energy converters into the WindFloat, resulting in a new concept called the WindWaveFloat (WWF). The concentration of several devices on one platform could offer a potential for both economic and operational advantages. Wind and wave energy converters can share the electrical cable and power transfer equipment to transport the electricity to shore. Access to multiple generation devices could be simplified, resulting in cost saving at the operational level. Overall capital costs may also be reduced, provided that the design of the foundation can be adapted to multiple devices with minimum modifications. Finally, the WindWaveFloat confers the ability to increase energy production from individual floating support structures, potentially leading to a reduction in levelized energy costs, an increase in the overall capacity factor, and greater stability of the electrical power delivered to the grid. The research conducted under this grant investigated the integration of several wave energy device types into the WindFloat platform. Several of the resulting system designs demonstrated technical feasibility, but the size and design constraints of the wave energy converters (technical and economic) make the WindWaveFloat concept economically unfeasible at this time. Not enough additional generation could be produced to make the additional expense associated with wave energy conversion integration into the WindFloat worthwhile.

  11. The digital agenda of virtual currencies: Can BitCoin become a global currency?

    OpenAIRE

    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...

  12. Universality and clustering in 1 + 1 dimensional superstring-bit models

    International Nuclear Information System (INIS)

    Bergman, O.; Thorn, C.B.

    1996-01-01

    We construct a 1+1 dimensional superstring-bit model for D=3 Type IIB superstring. This low dimension model escapes the problem encountered in higher dimension models: (1) It possesses full Galilean supersymmetry; (2) For noninteracting Polymers of bits, the exactly soluble linear superpotential describing bit interactions is in a large universality class of superpotentials which includes ones bounded at spatial infinity; (3) The latter are used to construct a superstring-bit model with the clustering properties needed to define an S-matrix for closed polymers of superstring-bits

  13. Floating arterial thrombus related stroke treated by intravenous thrombolysis.

    Science.gov (United States)

    Vanacker, P; Cordier, M; Janbieh, J; Federau, C; Michel, P

    2014-01-01

    The effects of intravenous thrombolysis on floating thrombi in cervical and intracranial arteries of acute ischemic stroke patients are unknown. Similarly, the best prevention methods of early recurrences remain controversial. This study aimed to describe the clinical and radiological outcome of thrombolyzed strokes with floating thrombi. We retrospectively analyzed all thrombolyzed stroke patients in our institution between 2003 and 2010 with floating thrombi on acute CT-angiography before the intravenous thrombolysis. The floating thrombus was diagnosed if an elongated thrombus of at least 5 mm length, completely surrounded by contrast on supra-aortic neck or intracerebral arteries, was present on CT-angiography. Demographics, vascular risk factors, and comorbidities were recorded and stroke etiology was determined after a standardized workup. Repeat arterial imaging was performed by CTA at 24 h or before if clinical worsening was noted and then by Doppler and MRA during the first week and at four months. Of 409 thrombolyzed stroke patients undergoing acute CT Angiography, seven (1.7%) had a floating thrombus; of these seven, six had it in the anterior circulation. Demographics, risk factors and stroke severity of these patients were comparable to the other thrombolyzed patients. After intravenous thrombolysis, the floating thrombi resolved completely at 24 h in four of the patients, whereas one had an early recurrent stroke and one developed progressive worsening. One patient developed early occlusion of the carotid artery with floating thrombus and subsequently a TIA. The two patients with a stable floating thrombus had no clinical recurrences. In the literature, only one of four reported cases were found to have a thrombolysis-related early recurrence. Long-term outcome seemed similar in thrombolyzed patients with floating thrombus, despite a possible increase of very early recurrence. It remains to be established whether acute mechanical thrombectomy could be

  14. Input Stage for Low-Voltage, Low-Noise Preamplifiers Based on a Floating-Gate MOS Transistor

    DEFF Research Database (Denmark)

    Igor, Mucha

    1997-01-01

    A novel input stage for low-voltage, low-noise preamplifiers for integrated capacitive sensors is presented. The input stage of the preamplifier employs floating-gate MOS transistors which are capable of storing the operation point of the input stage over several years without any severe degradat......A novel input stage for low-voltage, low-noise preamplifiers for integrated capacitive sensors is presented. The input stage of the preamplifier employs floating-gate MOS transistors which are capable of storing the operation point of the input stage over several years without any severe...... degradation of the performance of the circuit and without the need for a repeating programming. In this way the noise originating from any resistance previously used for the definition of the operating point is avoided completely and, moreover, by avoiding the input high-pass filter both the saturation...

  15. Elimination of fecal coliforms and F-specific RNA coliphage from oysters (Crassostrea virginica) relaid in floating containers.

    Science.gov (United States)

    Kator, H; Rhodes, M

    2001-06-01

    Declining oyster (Crassostrea virginica) production in the Chesapeake Bay has stimulated aquaculture based on floats for off-bottom culture. While advantages of off-bottom culture are significant, the increased use of floating containers raises public health and microbiological concerns, because oysters in floats may be more susceptible to fecal contamination from storm runoff compared to those cultured on-bottom. We conducted four commercial-scale studies with market-size oysters naturally contaminated with fecal coliforms (FC) and a candidate viral indicator, F-specific RNA (FRNA) coliphage. To facilitate sampling and to test for location effects, 12 replicate subsamples, each consisting of 15 to 20 randomly selected oysters in plastic mesh bags, were placed at four characteristic locations within a 0.6- by 3.0-m "Taylor" float, and the remaining oysters were added to a depth not exceeding 15.2 cm. The float containing approximately 3,000 oysters was relaid in the York River, Virginia, for 14 days. During relay, increases in shellfish FC densities followed rain events such that final mean levels exceeded initial levels or did not meet an arbitrary product end point of 50 FC/100 ml. FRNA coliphage densities decreased to undetectable levels within 14 days (16 to 28 degrees C) in all but the last experiment, when temperatures fell between 12 and 16 degrees C. Friedman (nonparametric analysis of variance) tests performed on FC/Escherichia coli and FRNA densities indicated no differences in counts as a function of location within the float. The public health consequences of these observations are discussed, and future research and educational needs are identified.

  16. Float level switch for a nuclear power plant containment vessel

    International Nuclear Information System (INIS)

    Powell, J.G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures

  17. Float level switch for a nuclear power plant containment vessel

    Science.gov (United States)

    Powell, James G.

    1993-01-01

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

  18. Floating cultivation of marine cyanobacteria using coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, M.; Yoshida, E.; Takeyama, H.; Matsunaga, T. [Tokyo University of Agriculture and Technology, Tokyo (Japan). Dept. of Biotetechnology

    2000-07-01

    The aim was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. The viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine microalgae was investigated. The marine cyanobacterium Synechococcus sp. NKBC 040607 was found to adhere to floating CFA blocks in liquid culture medium. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks.

  19. A preliminary study on the containment building integrity following BIT removal for nuclear power plant

    International Nuclear Information System (INIS)

    Jo, Jong Young; Song, Dong Soo; Byun, Choong Sub

    2008-01-01

    Boron Injection Tank(BIT) is a component of the Safety Injection System, which its sole function is to provide concentrated boric acid to the reactor coolant in order to mitigate the consequences of postulated main steamline break accidents. Although BIT plays an important role in mitigating the accident, high concentration of 20,000ppm causes valve leakage, clog of precipitation and continuous heat tracing have to be provided. For the removal of BIT, benchmarking analysis is performed between COPATTA code used in final safety analysis report and CONTEMPT code to be used this study. CONTEMPT is well compatible with COPATTA. The sensitivity study for integrity is performed for the three cases of full double ended rupture at 102% power with diesel generator failure, 3.4m 3 and 2400ppm BIT, 3.4m 3 and 0ppm BIT and no volume of BIT. The results show that the deactivation of BIT is plausible for success

  20. Analysis of Floating Buoy of a Wave Power Generating Jack-Up Platform Haiyuan 1

    Directory of Open Access Journals (Sweden)

    Date Li

    2013-01-01

    Full Text Available The paper focuses on the performance of floating buoys of a wave power generating jack-up platform called Haiyuan 1, in order to work out the optimum designed draft and hydraulic pressure. The performance of the buoy, especially its delivered power, is an important issue in designing oscillating buoy wave energy converter. In this case, major factors affect the performance including incident wave, designed draft, and hydraulic pressure on the buoy. To find out the relationship among design draft, hydraulic pressure, and delivered power, the key point is to precisely estimate wave induced motion of the buoy. Three-dimensional theory and time domain method based on potential theory were adopted in the paper. Unlike ship and other floating structures, motion of wave energy converter (WEC buoy in wave will be weakened because of energy take-off, which will cause significant draft changing with time. Thus, draft changing should be taken into consideration as well. In addition, green water problem occurs more frequently than that in ship and other floating structures and also might the reduce delivered power. Therefore, green water problem will also be taken into account when choosing the optimum designed draft and hydraulic pressure. The calculation indicates that the optimum designed draft is 0.935 m, while the optimum designed hydraulic pressure is 30 kN.

  1. Floating of Black Holes in Dimension of Information

    Science.gov (United States)

    Gholibeigian, Hassan; Gholibeigian, Ghasem; Gholibeigian, Kazem

    2016-10-01

    In our vision, there is dimension of information in addition of space-time's dimensions as the fifth dimension of the universe. All of the space-time, mater, and dark mater/energy are always floating in this dimension and whispering to its communication as well as black holes. Communication of information (CI) is done with each fundamental particle (string) from fifth dimension via its four animated sub-particles (sub-strings) for transferring a package of complete information of its quantum state in a Planck time. Fundamental particle after process of information by its sub-particles goes to its next stage while carries the stored processed information. CI as the ``fundamental symmetry'' leads all processes of the black holes as well as other phenomena. Every point of space-time needs on time to its new package, because duration of each processing is a Planck time. So, stored soft super-translation hairs in terms of soft gravitons or photons on black hole's horizon, or stored information on a holographic plate at the future boundary of the horizon [Hawking et al.] can be only accessible for particles which are in those positions (horizon and its boundary), not for other locations of black hole for their fast processing. AmirKabir University of Technology, Tehran, Iran.

  2. Debate - Trafficking as a Floating Signifier: The view from Brazil

    Directory of Open Access Journals (Sweden)

    Grupo Davida

    2015-04-01

    Full Text Available The fact that the United Nations (UN Trafficking Protocol is not an autochthonous product of the Brazilian political system has resulted in its being brought into that system as a ‘floating signifier’: something that does not point to any actual object or agreed upon meaning.[1] People who wish to criminalise prostitution have attempted to bend the Protocol in that direction while prostitutes’ rights groups have used it to critique current Brazilian laws, emphasising the need to distinguish migration for voluntary, consensual sex work from trafficking. Groups concerned with organ trafficking (a crime for which there are practically no proven cases in Brazil have managed to push their banner to the fore in the trafficking debate. Meanwhile, Brazil’s long-established and relatively successful anti-slave labour movement has been loath to ‘change their brand’, having already gained a considerable degree of institutionalisation prior to Brazil’s ratification of the Protocol in 2004. [1] C Lévi-Strauss, ‘Introduction à l'oeuvre de Marcel Mauss’ in Mauss, Sociologie et Anthropologie, Paris, 1950.

  3. Modeling of Bit Error Rate in Cascaded 2R Regenerators

    DEFF Research Database (Denmark)

    Öhman, Filip; Mørk, Jesper

    2006-01-01

    and the regenerating nonlinearity is investigated. It is shown that an increase in nonlinearity can compensate for an increase in noise figure or decrease in signal power. Furthermore, the influence of the improvement in signal extinction ratio along the cascade and the importance of choosing the proper threshold......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...

  4. Extending Landauer's bound from bit erasure to arbitrary computation

    Science.gov (United States)

    Wolpert, David

    The minimal thermodynamic work required to erase a bit, known as Landauer's bound, has been extensively investigated both theoretically and experimentally. However, when viewed as a computation that maps inputs to outputs, bit erasure has a very special property: the output does not depend on the input. Existing analyses of thermodynamics of bit erasure implicitly exploit this property, and thus cannot be directly extended to analyze the computation of arbitrary input-output maps. Here we show how to extend these earlier analyses of bit erasure to analyze the thermodynamics of arbitrary computations. Doing this establishes a formal connection between the thermodynamics of computers and much of theoretical computer science. We use this extension to analyze the thermodynamics of the canonical ``general purpose computer'' considered in computer science theory: a universal Turing machine (UTM). We consider a UTM which maps input programs to output strings, where inputs are drawn from an ensemble of random binary sequences, and prove: i) The minimal work needed by a UTM to run some particular input program X and produce output Y is the Kolmogorov complexity of Y minus the log of the ``algorithmic probability'' of Y. This minimal amount of thermodynamic work has a finite upper bound, which is independent of the output Y, depending only on the details of the UTM. ii) The expected work needed by a UTM to compute some given output Y is infinite. As a corollary, the overall expected work to run a UTM is infinite. iii) The expected work needed by an arbitrary Turing machine T (not necessarily universal) to compute some given output Y can either be infinite or finite, depending on Y and the details of T. To derive these results we must combine ideas from nonequilibrium statistical physics with fundamental results from computer science, such as Levin's coding theorem and other theorems about universal computation. I would like to ackowledge the Santa Fe Institute, Grant No

  5. 32 bit digital optical computer - A hardware update

    Science.gov (United States)

    Guilfoyle, Peter S.; Carter, James A., III; Stone, Richard V.; Pape, Dennis R.

    1990-01-01

    Such state-of-the-art devices as multielement linear laser diode arrays, multichannel acoustooptic modulators, optical relays, and avalanche photodiode arrays, are presently applied to the implementation of a 32-bit supercomputer's general-purpose optical central processing architecture. Shannon's theorem, Morozov's control operator method (in conjunction with combinatorial arithmetic), and DeMorgan's law have been used to design an architecture whose 100 MHz clock renders it fully competitive with emerging planar-semiconductor technology. Attention is given to the architecture's multichannel Bragg cells, thermal design and RF crosstalk considerations, and the first and second anamorphic relay legs.

  6. Quantum Bit Commitment and the Reality of the Quantum State

    Science.gov (United States)

    Srikanth, R.

    2018-01-01

    Quantum bit commitment is insecure in the standard non-relativistic quantum cryptographic framework, essentially because Alice can exploit quantum steering to defer making her commitment. Two assumptions in this framework are that: (a) Alice knows the ensembles of evidence E corresponding to either commitment; and (b) system E is quantum rather than classical. Here, we show how relaxing assumption (a) or (b) can render her malicious steering operation indeterminable or inexistent, respectively. Finally, we present a secure protocol that relaxes both assumptions in a quantum teleportation setting. Without appeal to an ontological framework, we argue that the protocol's security entails the reality of the quantum state, provided retrocausality is excluded.

  7. 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...

  8. A 32-bit NMOS microprocessor with a large register file

    Science.gov (United States)

    Sherburne, R. W., Jr.; Katevenis, M. G. H.; Patterson, D. A.; Sequin, C. H.

    1984-10-01

    Two scaled versions of a 32-bit NMOS reduced instruction set computer CPU, called RISC II, have been implemented on two different processing lines using the simple Mead and Conway layout rules with lambda values of 2 and 1.5 microns (corresponding to drawn gate lengths of 4 and 3 microns), respectively. The design utilizes a small set of simple instructions in conjunction with a large register file in order to provide high performance. This approach has resulted in two surprisingly powerful single-chip processors.

  9. Equations of Motion of Free-Floating Spacecraft-Manipulator Systems: An Engineer's Tutorial

    Directory of Open Access Journals (Sweden)

    Markus Wilde

    2018-04-01

    Full Text Available The paper provides a step-by-step tutorial on the Generalized Jacobian Matrix (GJM approach for modeling and simulation of spacecraft-manipulator systems. The General Jacobian Matrix approach describes the motion of the end-effector of an underactuated manipulator system solely by the manipulator joint rotations, with the attitude and position of the base-spacecraft resulting from the manipulator motion. The coupling of the manipulator motion with the base-spacecraft are thus expressed in a generalized inertia matrix and a GJM. The focus of the paper lies on the complete analytic derivation of the generalized equations of motion of a free-floating spacecraft-manipulator system. This includes symbolic analytic expressions for all inertia property matrices of the system, including their time derivatives and joint-angle derivatives, as well as an expression for the generalized Jacobian of a generic point on any link of the spacecraft-manipulator system. The kinematics structure of the spacecraft-manipulator system is described both in terms of direction-cosine matrices and unit quaternions. An additional important contribution of this paper is to propose a new and more detailed definition for the modes of maneuvering of a spacecraft-manipulator. In particular, the two commonly used categories free-flying and free-floating are expanded by the introduction of five categories, namely floating, rotation-floating, rotation-flying, translation-flying, and flying. A fully-symbolic and a partially-symbolic option for the implementation of a numerical simulation model based on the proposed analytic approach are introduced and exemplary simulation results for a planar four-link spacecraft-manipulator system and a spatial six-link spacecraft manipulator system are presented.

  10. Improved energy performance of ammonia recycling system using floating condensing temperature control

    International Nuclear Information System (INIS)

    Lu, Wei; Meng, Zhuo; Sun, Yize; Zhong, Qianwen; Zhu, Helei

    2016-01-01

    Highlights: • Thermodynamic models for the compressor and evaporative condenser were developed. • An evaluation index was proposed to determine the optimal set point. • An algorithm was presented to compute the optimal set point. • Strategies for operating ammonia recycling system were proposed. - Abstract: Aiming at reducing the energy-consumption of ammonia recycling system, we presented floating condensing temperature control to maximize the coefficient of performance (COP) of the system. Firstly, thermodynamic models for the compressor and evaporative condenser were developed respectively. Then, an evaluation index and a solution scheme were proposed to determine the optimal set point of condensing temperature and the corresponding compressor speed. It is found that the system COP can be maximized by controlling the compressor speed to adjust the set point based on any given operating conditions. When the wet-bulb temperature is 22 °C, the system COP could be improved by 19.2–27.6% under floating condensing temperature control.

  11. A Method for Modeling of Floating Vertical Axis Wind Turbine

    DEFF Research Database (Denmark)

    Wang, Kai; Hansen, Martin Otto Laver; Moan, Torgeir

    2013-01-01

    It is of interest to investigate the potential advantages of floating vertical axis wind turbine (FVAWT) due to its economical installation and maintenance. A novel 5MW vertical axis wind turbine concept with a Darrieus rotor mounted on a semi-submersible support structure is proposed in this paper....... In order to assess the technical and economic feasibility of this novel concept, a comprehensive simulation tool for modeling of the floating vertical axis wind turbine is needed. This work presents the development of a coupled method for modeling of the dynamics of a floating vertical axis wind turbine....... This integrated dynamic model takes into account the wind inflow, aerodynamics, hydrodynamics, structural dynamics (wind turbine, floating platform and the mooring lines) and a generator control. This approach calculates dynamic equilibrium at each time step and takes account of the interaction between the rotor...

  12. Can Heavier Liquid Float on Top of a Lighter One?

    International Nuclear Information System (INIS)

    Ayyad, A. H.; Takrori, F.

    2011-01-01

    We report on a first observation of a floating spherical Hg (density 13 g/cm 3 ) drop on top of a glycerin (density 1.26 g/cm 3 ) drop, the latter is hemispherical and about four times larger in volume. This observation is clearly against nature's gravity law and has never been reported before. Here we present spectacular high resolution photos that clearly demonstrate this remarkable floating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of tap water displays the same phenomenon. Increasing the volume of the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is found enough to show the same floating phenomenon. This floating mercury as a phenomenon is puzzling. On this length scale it seems that surface tension and curvature dominate over gravity. (fundamental areas of phenomenology (including applications))

  13. Wave transmission prediction of multilayer floating breakwater using neural network

    Digital Repository Service at National Institute of Oceanography (India)

    Mandal, S.; Patil, S.G.; Hegde, A.V.

    In the present study, an artificial neural network method has been applied for wave transmission prediction of multilayer floating breakwater. Two neural network models are constructed based on the parameters which influence the wave transmission...

  14. Multifractal analysis of managed and independent float exchange rates

    Science.gov (United States)

    Stošić, Darko; Stošić, Dusan; Stošić, Tatijana; Stanley, H. Eugene

    2015-06-01

    We investigate multifractal properties of daily price changes in currency rates using the multifractal detrended fluctuation analysis (MF-DFA). We analyze managed and independent floating currency rates in eight countries, and determine the changes in multifractal spectrum when transitioning between the two regimes. We find that after the transition from managed to independent float regime the changes in multifractal spectrum (position of maximum and width) indicate an increase in market efficiency. The observed changes are more pronounced for developed countries that have a well established trading market. After shuffling the series, we find that the multifractality is due to both probability density function and long term correlations for managed float regime, while for independent float regime multifractality is in most cases caused by broad probability density function.

  15. High voltage switches having one or more floating conductor layers

    Science.gov (United States)

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  16. WindFloat Pacific Project, Final Scientific and Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Banister, Kevin [Principle Power, Inc., Emeryville, CA (United States)

    2017-01-17

    PPI’s WindFloat Pacific project (WFP) was an up to 30 MW floating offshore wind demonstration project proposed off the Coast of Oregon. The project was to be sited approximately 18 miles due west of Coos Bay, in over 1000 ft. of water, and is the first floating offshore wind array proposed in the United States, and the first offshore wind project of any kind proposed off the West Coast. PPI’s WindFloat, a semi-submersible foundation designed for high-capacity (6MW+) offshore wind turbines, is at the heart of the proposed project, and enables access to the world class wind resource at the project site and, equally, to other deep water, high wind resource areas around the country.

  17. Review of radiological problems of floating nuclear power plants

    International Nuclear Information System (INIS)

    Rodd, T.

    1982-01-01

    Radiological problems associated with floating nuclear power plants under both normal operation and accident conditions are discussed. In the latter case, aspects of both the airborne and liquid pathways are reviewed

  18. Bayesian signal reconstruction for 1-bit compressed sensing

    International Nuclear Information System (INIS)

    Xu, Yingying; Kabashima, Yoshiyuki; Zdeborová, Lenka

    2014-01-01

    The 1-bit compressed sensing framework enables the recovery of a sparse vector x from the sign information of each entry of its linear transformation. Discarding the amplitude information can significantly reduce the amount of data, which is highly beneficial in practical applications. In this paper, we present a Bayesian approach to signal reconstruction for 1-bit compressed sensing and analyze its typical performance using statistical mechanics. As a basic setup, we consider the case that the measuring matrix Φ has i.i.d entries and the measurements y are noiseless. Utilizing the replica method, we show that the Bayesian approach enables better reconstruction than the l 1 -norm minimization approach, asymptotically saturating the performance obtained when the non-zero entry positions of the signal are known, for signals whose non-zero entries follow zero mean Gaussian distributions. We also test a message passing algorithm for signal reconstruction on the basis of belief propagation. The results of numerical experiments are consistent with those of the theoretical analysis. (paper)

  19. Device-independent bit commitment based on the CHSH inequality

    International Nuclear Information System (INIS)

    Aharon, N; Massar, S; Pironio, S; Silman, J

    2016-01-01

    Bit commitment and coin flipping occupy a unique place in the device-independent landscape, as the only device-independent protocols thus far suggested for these tasks are reliant on tripartite GHZ correlations. Indeed, we know of no other bipartite tasks, which admit a device-independent formulation, but which are not known to be implementable using only bipartite nonlocality. Another interesting feature of these protocols is that the pseudo-telepathic nature of GHZ correlations—in contrast to the generally statistical character of nonlocal correlations, such as those arising in the violation of the CHSH inequality—is essential to their formulation and analysis. In this work, we present a device-independent bit commitment protocol based on CHSH testing, which achieves the same security as the optimal GHZ-based protocol, albeit at the price of fixing the time at which Alice reveals her commitment. The protocol is analyzed in the most general settings, where the devices are used repeatedly and may have long-term quantum memory. We also recast the protocol in a post-quantum setting where both honest and dishonest parties are restricted only by the impossibility of signaling, and find that overall the supra-quantum structure allows for greater security. (paper)

  20. Giga-bit optical data transmission module for Beam Instrumentation

    CERN Document Server

    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...

  1. Reexamination of quantum bit commitment: The possible and the impossible

    International Nuclear Information System (INIS)

    D'Ariano, Giacomo Mauro; Kretschmann, Dennis; Schlingemann, Dirk; Werner, Reinhard F.

    2007-01-01

    Bit commitment protocols whose security is based on the laws of quantum mechanics alone are generally held to be impossible. We give a strengthened and explicit proof of this result. We extend its scope to a much larger variety of protocols, which may have an arbitrary number of rounds, in which both classical and quantum information is exchanged, and which may include aborts and resets. Moreover, we do not consider the receiver to be bound to a fixed 'honest' strategy, so that 'anonymous state protocols', which were recently suggested as a possible way to beat the known no-go results, are also covered. We show that any concealing protocol allows the sender to find a cheating strategy, which is universal in the sense that it works against any strategy of the receiver. Moreover, if the concealing property holds only approximately, the cheat goes undetected with a high probability, which we explicitly estimate. The proof uses an explicit formalization of general two-party protocols, which is applicable to more general situations, and an estimate about the continuity of the Stinespring dilation of a general quantum channel. The result also provides a natural characterization of protocols that fall outside the standard setting of unlimited available technology and thus may allow secure bit commitment. We present such a protocol whose security, perhaps surprisingly, relies on decoherence in the receiver's laboratory

  2. Reexamination of quantum bit commitment: The possible and the impossible

    Science.gov (United States)

    D'Ariano, Giacomo Mauro; Kretschmann, Dennis; Schlingemann, Dirk; Werner, Reinhard F.

    2007-09-01

    Bit commitment protocols whose security is based on the laws of quantum mechanics alone are generally held to be impossible. We give a strengthened and explicit proof of this result. We extend its scope to a much larger variety of protocols, which may have an arbitrary number of rounds, in which both classical and quantum information is exchanged, and which may include aborts and resets. Moreover, we do not consider the receiver to be bound to a fixed “honest” strategy, so that “anonymous state protocols,” which were recently suggested as a possible way to beat the known no-go results, are also covered. We show that any concealing protocol allows the sender to find a cheating strategy, which is universal in the sense that it works against any strategy of the receiver. Moreover, if the concealing property holds only approximately, the cheat goes undetected with a high probability, which we explicitly estimate. The proof uses an explicit formalization of general two-party protocols, which is applicable to more general situations, and an estimate about the continuity of the Stinespring dilation of a general quantum channel. The result also provides a natural characterization of protocols that fall outside the standard setting of unlimited available technology and thus may allow secure bit commitment. We present such a protocol whose security, perhaps surprisingly, relies on decoherence in the receiver’s laboratory.

  3. Multi-span Suspension Bridge with Floating Towers

    OpenAIRE

    Brunstad, Orjan

    2013-01-01

    The Norwegian Public Roads Administration (NPRA) is currently conducting a feasible study of crossing 8 fjords on the west coast of Norway. The most challenging crossing is the 3700 m wide Sognefjord. Three main concepts are under development, and one of the concepts of this crossing is a three span suspension bridge on floating towers. The floating foundation suggested is a multi-column pontoon with mooring lines to seabed. The object of this thesis was to study this bridge concept with resp...

  4. Sustainability and the future of managed floating in China

    OpenAIRE

    Švarc, Jiří

    2009-01-01

    The purpose of this thesis is to study the Balance of Payments and the Exchange Rate of the People's Republic of China, and it aims to assess whether the current performance of their Managed Floating Exchange Rate is sustainable in the future (given the equilibrium of China's Balance of Payments) and examine what effect would a Free Floating Renminbi Exchange Rate have on the Chinese economy. The work uses the method of compilation - gathering and organizing information on the development of ...

  5. Entropie analysis of floating car data systems

    Directory of Open Access Journals (Sweden)

    F. Gössel

    2004-01-01

    Full Text Available The knowledge of the actual traffic state is a basic prerequisite of modern traffic telematic systems. Floating Car Data (FCD systems are becoming more and more important for the provision of actual and reliable traffic data. In these systems the vehicle velocity is the original variable for the evaluation of the current traffic condition. As real FCDsystems are operating under conditions of limited transmission and processing capacity the analysis of the original variable vehicle speed is of special interest. Entropy considerations are especially useful for the deduction of fundamental restrictions and limitations. The paper analyses velocity-time profiles by means of information entropy. It emphasises in quantification of the information content of velocity-time profiles and the discussion of entropy dynamic in velocity-time profiles. Investigations are based on empirical data derived during field trials. The analysis of entropy dynamic is carried out in two different ways. On one hand velocity differences within a certain interval of time are used, on the other hand the transinformation between velocities in certain time distances was evaluated. One important result is an optimal sample-rate for the detection of velocity data in FCD-systems. The influence of spatial segmentation and of different states of traffic was discussed.

  6. Enhancing Water Evaporation with Floating Synthetic Leaves

    Science.gov (United States)

    Boreyko, Jonathan; Vieitez, Joshua; Berrier, Austin; Roseveare, Matthew; Shi, Weiwei

    2017-11-01

    When a wetted nanoporous medium is exposed to a subsaturated ambient environment, the water menisci assume a concave curvature to achieve a negative pressure. This negative water pressure is required to balance the mismatch in water activity across the water-air interface to achieve local equilibrium. Here, we show that the diffusive evaporation rate of water can be greatly modulated by floating a nanoporous synthetic leaf at the water's free interface. For high ambient humidities, adding the leaf serves to enhance the evaporation rate, presumably by virtue of the menisci enhancing the effective liquid-vapor surface area. For low humidities, the menisci cannot achieve a local equilibrium and retreat partway into the leaf, which increases the local humidity directly above the menisci. In light of these two effects, we find the surprising result that leaves exposed to an ambient humidity of 90 percent can evaporate water at the same rate as leaves exposed to only 50 percent humidity. These findings have implications for using synthetic trees to enhance steam generation or water harvesting. This work was supported by the National Science Foundation (CBET-1653631).

  7. Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

    Science.gov (United States)

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2011-12-01

    The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

  8. Equipment and materials for coupling interfaces of a nuclear reactor with desalination and heating plants based on floating NHPS

    International Nuclear Information System (INIS)

    Panov, Yu.K.; Polunichev, V.I.

    1998-01-01

    Intensive design activity is currently underway in Russia on floating nuclear installations, relying on proven marine NSSSs of KLT-40-type, which are capable of generating electricity, producing potable water and heat for industrial and district heating purposes. In particular, design work of the first floating power unit for a pilot nuclear co-generation station, which is due to be situated at the Pevek port area in the Chukotsky national district (extreme north-east of Russia), is approaching completion, and preparatory work is being carried out for fabrication of its most labour-intensive components. Work is also in progress together with 'CANDESAL Inc. (Canada)' on the conceptual design of a floating power-desalination complex. Most suitable options of floating power-desalination complexes are being sought, addressing requirements of potential customers. Earlier, at the IAEA technical committee meeting (1993) it was shown that a complex, which combines a highly effective condensation turbine and a modem reverse-osmosis desalination facility, could be considered as most preferable from the view point of efficient utilisation of thermal energy generated by nuclear reactors for co-production of potable water and electricity. The prospective technology for sea water desalination by a reverse-osmosis method is being developed in particular by 'CANDESAL Inc.'. It was also pointed out that another sufficiently efficient installation for potable water and electricity co-production is a dual-purpose complex which integrates both condensation and back-pressure turbines and a distillation desalination facility. Similar flow configurations were adopted for the nuclear desalination complex at Aktau (Kazakhstan) which has been in operation since 1972. 'SverdNIIKhimMash' institute (Ekaterinburg) is a Russian leading designer of modem distillation desalination facilities. This paper presents heat and fluid diagrams of floating complexes, brief description of their key

  9. Neuro System Structure for Vehicle Recognition and Count in Floating Bridge Specific Conditions

    Directory of Open Access Journals (Sweden)

    Slobodan Beroš

    2012-10-01

    Full Text Available The paper presents the research of the sophisticated vehiclerecognition and count system based on the application of theneural network. The basic elements of neural network andadaptive logic network for object recognition are discussed. Theadaptive logic network solution ability based on simple digitalcircuits as crucial in real-time applications is pointed out. Thesimulation based on the use of reduced high level noise pictureand a tree 2. 7. software have shown excellent results. The consideredand simulated adaptive neural network based systemwith its good recognition and convergence is a useful real-timesolution for vehicle recognition and count in the floating bridgesevere conditions.

  10. Implementation of RSA 2048-bit and AES 256-bit with Digital Signature for Secure Electronic Health Record Application

    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.

  11. Scaling vectors of attoJoule per bit modulators

    Science.gov (United States)

    Sorger, Volker J.; Amin, Rubab; Khurgin, Jacob B.; Ma, Zhizhen; Dalir, Hamed; Khan, Sikandar

    2018-01-01

    Electro-optic modulation performs the conversion between the electrical and optical domain with applications in data communication for optical interconnects, but also for novel optical computing algorithms such as providing nonlinearity at the output stage of optical perceptrons in neuromorphic analog optical computing. While resembling an optical transistor, the weak light-matter-interaction makes modulators 105 times larger compared to their electronic counterparts. Since the clock frequency for photonics on-chip has a power-overhead sweet-spot around tens of GHz, ultrafast modulation may only be required in long-distance communication, not for short on-chip links. Hence, the search is open for power-efficient on-chip modulators beyond the solutions offered by foundries to date. Here, we show scaling vectors towards atto-Joule per bit efficient modulators on-chip as well as some experimental demonstrations of novel plasmonic modulators with sub-fJ/bit efficiencies. Our parametric study of placing different actively modulated materials into plasmonic versus photonic optical modes shows that 2D materials overcompensate their miniscule modal overlap by their unity-high index change. Furthermore, we reveal that the metal used in plasmonic-based modulators not only serves as an electrical contact, but also enables low electrical series resistances leading to near-ideal capacitors. We then discuss the first experimental demonstration of a photon-plasmon-hybrid graphene-based electro-absorption modulator on silicon. The device shows a sub-1 V steep switching enabled by near-ideal electrostatics delivering a high 0.05 dB V-1 μm-1 performance requiring only 110 aJ/bit. Improving on this demonstration, we discuss a plasmonic slot-based graphene modulator design, where the polarization of the plasmonic mode aligns with graphene’s in-plane dimension; where a push-pull dual-gating scheme enables 2 dB V-1 μm-1 efficient modulation allowing the device to be just 770 nm

  12. Influence of different types of low substituted hydroxypropyl cellulose on tableting, disintegration, and floating behaviour of floating drug delivery systems.

    Science.gov (United States)

    Diós, Péter; Pernecker, Tivadar; Nagy, Sándor; Pál, Szilárd; Dévay, Attila

    2015-11-01

    The object of the present study is to evaluate the effect of application of low-substituted hydroxypropyl cellulose (L-HPC) 11 and B1 as excipients promoting floating in gastroretentive tablets. Directly compressed tablets were formed based on experimental design. Face-centred central composite design was applied with two factors and 3 levels, where amount of sodium alginate (X 1) and L-HPC (X2 ) were the numerical factors. Applied types of L-HPCs and their 1:1 mixture were included in a categorical factor (X 3). Studied parameters were floating lag time, floating time, floating force, swelling behaviour of tablets and dissolution of paracetamol, which was used as a model active substance. Due to their physical character, L-HPCs had different water uptake and flowability. Lower flowability and lower water uptake was observed after 60 min at L-HPC 11 compared to L-HPC B1. Shorter floating times were detected at L-HPC 11 and L-HPC mixtures with 0.5% content of sodium alginate, whereas alginate was the only significant factor. Evaluating results of drug release and swelling studies on floating tablets revealed correlation, which can serve to help to understand the mechanism of action of L-HPCs in the field development of gastroretentive dosage forms.

  13. Position control of a floating nuclear power plant

    International Nuclear Information System (INIS)

    Motohashi, K.; Hamamoto, T.; Sasaki, R.; Kojima, M.

    1993-01-01

    In spite of the increasing demand of electricity in Japan, the sites of nuclear power plants suitable for conventional seismic regulations become severely limited. Under these circumstances, several types of advanced siting technology have been developed. Among them, floating power plants have a great advantage of seismic isolation that leads to the seismic design standardization and factory fabrication. The feasibility studies or preliminary designs of floating power plants enclosed by breakwaters in the shallow sea have been carried out last two decades in U.S. and Japan. On the other hand, there are few investigations on the dynamic behavior of floating power plants in the deep sea. The offshore floating nuclear power plants have an additional advantage in that large breakwaters are not required, although the safety checking is inevitable against wind-induced waves. The tension-leg platforms which have been constructed for oil drilling in the deep sea seem to be a promising offshore siting technology of nuclear power plants. The tension-leg mooring system can considerably restrain the heave and pitch of a floating power plant because of significant stiffness in the vertical direction. Different from seismic effects, wind-induced waves may be predicted in advance by making use of ocean weather forecasts using artificial satellites. According to the wave prediction, the position of the floating plant may be controlled by adjusting the water content in ballast tanks and the length of tension-legs before the expected load arrives. The position control system can reduce the wave force acting on the plant and to avoid the unfavorable response behavior of the plant. In this study a semi-submerged circular cylinder with tension-legs is considered as a mathematical model. The configuration of circular cylinder is effective because the dynamic behavior does not depend on incident wave directions. It is also unique in that it can obtain the closed-form solution of

  14. Brownian motion properties of optoelectronic random bit generators based on laser chaos.

    Science.gov (United States)

    Li, Pu; Yi, Xiaogang; Liu, Xianglian; Wang, Yuncai; Wang, Yongge

    2016-07-11

    The nondeterministic property of the optoelectronic random bit generator (RBG) based on laser chaos are experimentally analyzed from two aspects of the central limit theorem and law of iterated logarithm. The random bits are extracted from an optical feedback chaotic laser diode using a multi-bit extraction technique in the electrical domain. Our experimental results demonstrate that the generated random bits have no statistical distance from the Brownian motion, besides that they can pass the state-of-the-art industry-benchmark statistical test suite (NIST SP800-22). All of them give a mathematically provable evidence that the ultrafast random bit generator based on laser chaos can be used as a nondeterministic random bit source.

  15. Shuttle bit rate synchronizer. [signal to noise ratios and error analysis

    Science.gov (United States)

    Huey, D. C.; Fultz, G. L.

    1974-01-01

    A shuttle bit rate synchronizer brassboard unit was designed, fabricated, and tested, which meets or exceeds the contractual specifications. The bit rate synchronizer operates at signal-to-noise ratios (in a bit rate bandwidth) down to -5 dB while exhibiting less than 0.6 dB bit error rate degradation. The mean acquisition time was measured to be less than 2 seconds. The synchronizer is designed around a digital data transition tracking loop whose phase and data detectors are integrate-and-dump filters matched to the Manchester encoded bits specified. It meets the reliability (no adjustments or tweaking) and versatility (multiple bit rates) of the shuttle S-band communication system through an implementation which is all digital after the initial stage of analog AGC and A/D conversion.

  16. Fatigue life of drilling bit bearings under arbitrary random loads

    Energy Technology Data Exchange (ETDEWEB)

    Talimi, M.; Farshidi, R. [Calgary Univ., AB (Canada)

    2009-07-01

    A fatigue analysis was conducted in order to estimate the bearing life of a roller cone rock bit under arbitrary random loads. The aim of the study was to reduce bearing failures that can interrupt well operations. Fatigue was considered as the main reason for bearing failure. The expected value of cumulative fatigue damage was used to estimate bearing life. An equation was used to express the relation between bearing life and bearing load when the bearing was subjected to a steady load and constant speed. The Palmgren-Miner hypothesis was used to determine the ultimate tensile strength of the material. The rain flow counting principle was used to determine distinct amplitude cycles. Hertzian equations were used to determine maximum stress loads. Fourier series were used to obtain simple harmonic functions for estimating stress-life relations. It was concluded that the method can be used during the well planning phase to prevent bearing failures. 6 refs.

  17. Geneva University - Superconducting flux quantum bits: fabricated quantum objects

    CERN Multimedia

    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 ...

  18. ALAT SOLAR TRACKER BERBASIS MIKROKONTROLER 8 BIT ATMega8535

    Directory of Open Access Journals (Sweden)

    I Wayan Sutaya

    2015-07-01

    Full Text Available Penelitian yang telah dilakukan ini adalah membuat prototipe alat solar tracker. Alat ini berfungsi untuk menggerakkan modul sel surya sehingga permukaan sel surya bisa terkena sinar matahari secara maksimal. Saat ini sel surya di Indonesia banyak terpasang secara statis atau tidak dilengkapi alat solar tracker sehingga energi matahari tidak diterima secara maksimal. Hal ini menyebabkan sel surya yang terpasang di beberapa daerah di Indonesia tidak memberikan manfaat yang optimal. Alat solar tracker yang dihasilkan pada penelitian ini diharapkan sebagai solusi dari permasalahan yang ada saat ini. Mikrokontroler 8 bit ATMega8535 yang digunakan sebagai otak utama dari alat solar tracker menjadikan alat ini menjadi berbiaya murah. Serta teknik memprogram dengan bahasa assembly menjadikan alat ini tahan terhadap kegagalan sistem. Solar tracker ini sudah bisa beroperasi dengan baik dan cocok digunakan pada modul sel surya berukuran kecil.

  19. Bitlis Etnografya Müzesi'nde Bulunan Geleneksel Giysiler

    OpenAIRE

    Sökmen, Sultan

    2016-01-01

    Bu çalışmada, Bitlis Etnografya Müzesi'nde sergilenmekte olan geleneksel giysilerin kumaş, renk, süsleme ve teknik özelliklerinin tanıtımı amaçlanmıştır. Bu amaç doğrultusunda ilgili makamlardan yazılı izin alınarak müze vitrinlerinde sergilenmekte olan ve depolarda koruma altına alınan giysilerin fotoğrafları çekilmiş, gerekli ölçümleri yapılarak teknik özellikleri belirlenmiş, hammadde ve süsleme özellikleri incelenmiştir. Müzede bulunan geleneksel giysi örnekleri yeterince zengin olma...

  20. A low power 12-bit ADC for nuclear instrumentation

    International Nuclear Information System (INIS)

    Adachi, R.; Landis, D.; Madden, N.; Silver, E.; LeGros, M.

    1992-10-01

    A low power, successive approximation, analog-to-digital converter (ADC) for low rate, low cost, battery powered applications is described. The ADC is based on a commercial 50 mW successive approximation CMOS device (CS5102). An on-chip self-calibration circuit reduces the inherent differential nonlinearity to 7%. A further reduction of the differential nonlinearity to 0.5% is attained with a four bit Gatti function. The Gatti function is distributed to minimize battery power consumption. All analog functions reside with the ADC while the noisy digital functions reside in the personal computer based histogramming memory. Fiber optic cables carry afl digital information between the ADC and the personal computer based histogramming memory

  1. Bit-string physics: A novel theory of everything

    International Nuclear Information System (INIS)

    Noyes, H.P.

    1994-08-01

    We encode the quantum numbers of the standard model of quarks and leptons using constructed bitstrings of length 256. These label a grouting universe of bit-strings of growing length that eventually construct a finite and discrete space-time with reasonable cosmological properties. Coupling constants and mass ratios, computed from closure under XOR and a statistical hypothesis, using only ℎ, c and m p to fix our units of mass, length and time in terms of standard (meterkilogram-second) metrology, agree with the first four to seven significant figures of accepted experimental results. Finite and discrete conservation laws and commutation relations insure the essential characteristics of relativistic quantum mechanics, including particle-antiparticle pair creation. The correspondence limit in (free space) Maxwell electromagnetism and Einstein gravitation is consistent with the Feynman-Dyson-Tanimura ''proof.''

  2. Bit-string physics: A novel theory of everything

    Energy Technology Data Exchange (ETDEWEB)

    Noyes, H.P.

    1994-08-01

    We encode the quantum numbers of the standard model of quarks and leptons using constructed bitstrings of length 256. These label a grouting universe of bit-strings of growing length that eventually construct a finite and discrete space-time with reasonable cosmological properties. Coupling constants and mass ratios, computed from closure under XOR and a statistical hypothesis, using only {h_bar}, c and m{sub p} to fix our units of mass, length and time in terms of standard (meterkilogram-second) metrology, agree with the first four to seven significant figures of accepted experimental results. Finite and discrete conservation laws and commutation relations insure the essential characteristics of relativistic quantum mechanics, including particle-antiparticle pair creation. The correspondence limit in (free space) Maxwell electromagnetism and Einstein gravitation is consistent with the Feynman-Dyson-Tanimura ``proof.``

  3. 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.

  4. Bit-Serial Adder Based on Quantum Dots

    Science.gov (United States)

    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

  5. "Push back" technique: A simple method to remove broken drill bit from the proximal femur.

    Science.gov (United States)

    Chouhan, Devendra K; Sharma, Siddhartha

    2015-11-18

    Broken drill bits can be difficult to remove from the proximal femur and may necessitate additional surgical exploration or special instrumentation. We present a simple technique to remove a broken drill bit that does not require any special instrumentation and can be accomplished through the existing incision. This technique is useful for those cases where the length of the broken drill bit is greater than the diameter of the bone.

  6. Computer-Aided Design for Built-In-Test (CADBIT) - BIT Library. Volume 2

    Science.gov (United States)

    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

  7. 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.

  8. Pengaruh Frekuensi Melihat Iklan Floating terhadap Tingkat Kesadaran Merek

    Directory of Open Access Journals (Sweden)

    Forddhanto Bimantoro

    2013-11-01

    Full Text Available Abstract: Floating ad  is online advertisement aiming to stimulate brand awareness by increasing familiarity through reexposing advertisement. This research examines the influence of ARCO Depok members’ exposure of floating ad at www.detik.com to their brand awareness about Samsung LED TV. The frequency of consuming the advertisement is differentiated into three categories, namely three times, five times and never. The result shows that the respondents’ exposure of floating ad could influence the level of brand awareness as much as 40.7%. However, this tendency was not represented in the category of five times. The result also shows that the only control variable which was able to significantly influence the level of brand awareness was the variable of respondents’ visitation to the site of detik.com. Abstrak: Iklan floating merupakan iklan di media internet yang bertujuan mencapai kesadaran merek dengan cara meningkatkan familiarity melalui frekuensi pengulangan iklan. Frekuensi melihat iklan floating dibedakan  dengan memilah kelompok responden yang dikenai frekuensi melihat iklan 3 kali, 5 kali dan tidak melihat iklan. Penelitian ini menguji pengaruh frekuensi melihat iklan floating di www.detik.com terhadap tingkat kesadaran merek Samsung LED TV pada warga ARCO Depok, Jawa Barat. Hasil penelitian menunjukkan bahwa frekuensi melihat iklan floating dapat mempengaruhi tingkat kesadaran merek sebesar 40,7%; namun tidak terbukti pada kelompok yang melihat iklan sebanyak lima kali. Variabel kontrol yang mampu mempengaruhi tingkat kesadaran merek secara signifikan hanya variabel kunjungan responden ke detik.com.Â

  9. The study to estimate the floating population in Seoul, Korea.

    Science.gov (United States)

    Lee, Geon Woo; Lee, Yong Jin; Kim, Youngeun; Hong, Seung-Han; Kim, Soohwaun; Kim, Jeong Soo; Lee, Jong Tae; Shin, Dong Chun; Lim, Youngwook

    2017-01-01

    Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

  10. The study to estimate the floating population in Seoul, Korea

    Directory of Open Access Journals (Sweden)

    Geon Woo Lee

    2017-05-01

    Full Text Available Traffic-related pollutants have been reported to increase the morbidity of respiratory diseases. In order to apply management policies related to motor vehicles, studies of the floating population living in cities are important. The rate of metro rail transit system use by passengers residing in Seoul is about 54% of total public transportation use. Through the rate of metro use, the people-flow ratios in each administrative area were calculated. By applying a people-flow ratio based on the official census count, the floating population in 25 regions was calculated. The reduced level of deaths among the floating population in 14 regions having the roadside monitoring station was calculated as assuming a 20% reduction of mobile emission based on the policy. The hourly floating population size was calculated by applying the hourly population ratio to the regional population size as specified in the official census count. The number of people moving from 5 a.m. to next day 1 a.m. could not be precisely calculated when the population size was applied, but no issue was observed that would trigger a sizable shift in the rate of population change. The three patterns of increase, decrease, and no change of population in work hours were analyzed. When the concentration of particulate matter less than 10 μm in aerodynamic diameter was reduced by 20%, the number of excess deaths varied according to the difference of the floating population. The effective establishment of directions to manage the pollutants in cities should be carried out by considering the floating population. Although the number of people using the metro system is only an estimate, this disadvantage was supplemented by calculating inflow and outflow ratio of metro users per time in the total floating population in each region. Especially, 54% of metro usage in public transport causes high reliability in application.

  11. The Digital Agenda of Virtual Currencies. Can BitCoin Become a Global Currency?

    OpenAIRE

    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...

  12. Bit-depth scalable video coding with new inter-layer prediction

    Directory of Open Access Journals (Sweden)

    Chiang Jui-Chiu

    2011-01-01

    Full Text Available Abstract The rapid advances in the capture and display of high-dynamic range (HDR image/video content make it imperative to develop efficient compression techniques to deal with the huge amounts of HDR data. Since HDR device is not yet popular for the moment, the compatibility problems should be considered when rendering HDR content on conventional display devices. To this end, in this study, we propose three H.264/AVC-based bit-depth scalable video-coding schemes, called the LH scheme (low bit-depth to high bit-depth, the HL scheme (high bit-depth to low bit-depth, and the combined LH-HL scheme, respectively. The schemes efficiently exploit the high correlation between the high and the low bit-depth layers on the macroblock (MB level. Experimental results demonstrate that the HL scheme outperforms the other two schemes in some scenarios. Moreover, it achieves up to 7 dB improvement over the simulcast approach when the high and low bit-depth representations are 12 bits and 8 bits, respectively.

  13. Exploration of Least Significant Bit Based Watermarking and Its Robustness against Salt and Pepper Noise

    OpenAIRE

    Kamaldeep Joshi; Rajkumar Yadav; Sachin Allwadhi

    2016-01-01

    Image steganography is the best aspect of information hiding. In this, the information is hidden within an image and the image travels openly on the Internet. The Least Significant Bit (LSB) is one of the most popular methods of image steganography. In this method, the information bit is hidden at the LSB of the image pixel. In one bit LSB steganography method, the total numbers of the pixels and the total number of message bits are equal to each other. In this paper, the LSB method of image ...

  14. Designing embedded systems with 32-bit PIC microcontrollers and MikroC

    CERN Document Server

    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

  15. Tipping Point

    Medline Plus

    Full Text Available ... en español Blog About OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by ... danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe ...

  16. Star-Formation in Free-Floating Evaporating Gaseous Globules

    Science.gov (United States)

    Sahai, Raghvendra

    2017-08-01

    We propose to study the stellar embryos in select members of a newly recognized class of Free-floating Evaporating Gaseous Globules (frEGGS) embedded in HII regions and having head-tail shapes. We discovered two of these in the Cygnus massive star-forming region (MSFR) with HST, including one of the most prominent members of this class (IRAS20324). Subsequent archival searches of Spitzer imaging of MSFRs has allowed us to build a statistical sample of frEGGs. Our molecular-line observations show the presence of dense molecular cores with total gas masses of (0.5-few) Msun in these objects, and our radio continuum images and Halpha images (from the IPHAS survey) reveal bright photo-ionized peripheries around these objects. We hypothesize that frEGGs are density concentrations originating in giant molecular clouds, that, when subject to the sculpting and compression by strong winds and UV radiation from massive stars, become active star-forming cores. For the 4 frEGGs with HST or near-IR AO images showing young stars and bipolar cavities produced by their jets or collimated outflows, the symmetry axis points roughly toward the external ionizing star or star cluster - exciting new evidence for our overpressure-induced star formation hypothesis. We propose to test this hypothesis by imaging 24 frEGGs in two nearby MSFRs that represent different radiation-dominated environments. Using ACS imaging with filters F606W, F814W, & F658N (Ha+[NII]), we will search for jets and outflow-excavated cavities, investigate the stellar nurseries inside frEGGs, and determine whether the globules are generally forming multiple star systems or small clusters, as in IRAS20324.

  17. EnhancedBit: Unleashing the potential of the unchoking policy in the BitTorrent  protocol

    CERN Document Server

    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...

  18. Floating venous thrombi: diagnosis with spiral-CT-venography

    International Nuclear Information System (INIS)

    Gartenschlaeger, M.; Schmidt, J.A.

    1996-01-01

    Local application of contrast agent into an ipsilateral dorsal foot vein and spiral CT were used to examine 16 consecutive cases with deep venous thrombosis proven at conventional venography; in addition, colour Doppler flow imaging was performed. At conventional venography, 8/16 thrombi appeared to be floating and the remaining 8/16 were adherent to the vessel wall. Spiral-CT showed 15/16 thrombi to be adherent to the vessel wall; the floating thrombus correlated with findings in conventional venography. At colour Doppler flow imaging 3/16 thrombi were considered floating, one of them was discordant to conventional venography. The comparison of conventional venography to spiral-CT demonstrates complete agreement for adherence to vessel wall seen in conventional venography (p=1,0) and significant discordance in cases with free-floating appearance in conventional venography. Adherence of thrombi to the wall of the vessel at conventional venography is in agreement with computed tomography. Conventional venography probably overestimates the prevalence of free floating thrombi. (orig./MG) [de

  19. Preparation and comparitive analysis of MCNP thermal libraries for liquid hydrogen and deuterium using NJOY97 on 32 bit and 64 bit computers

    International Nuclear Information System (INIS)

    Jo, Y. S.; Kim, J. D.; Kil, C. S.; Jang, J. H.

    1999-01-01

    The scattering laws and MCNP thermal libraries for liquid hydrogen and deuterium are comparatively calculated on HP715 (32-bit computer) and SGI IP27 (64-bit computer) using NJOY97. The results are also compared with the experimental data. In addition, MCNP calculations for the nuclear design of a cold neutron source at HANARO are performed with the newly generated MCNP thermal libraries from two different computers and the results are compared

  20. Free-floating planets from microlensing

    Science.gov (United States)

    Sumi, Takahiro

    2014-06-01

    Gravitational microlensing has an unique sensitivity to exoplanets at outside of the snow-line and even exoplanets unbound to any host stars because the technique does not rely on any light from the host but the gravity of the lens. MOA and OGLE collaborations reported the discovery of a population of unbound or distant Jupiter-mass objects, which are almost twice (1.8_{-0.8}^{+1.7}) as common as main-sequence stars, based on two years of gravitational microlensing survey observations toward the Galactic Bulge. These planetary-mass objects have no host stars that can be detected within about ten astronomical units by gravitational microlensing. However a comparison with constraints from direct imaging suggests that most of these planetary-mass objects are not bound to any host star. The such short-timescale unbound planetary candidates have been detected with the similar rate in on-going observations and these groups are working to update the analysis with larger statistics. Recently, there are also discoveries of free-floating planetary mass objects by the direct imaging in young star-forming regions and in the moving groups, but these objects are limited to massive objects of 3 to 15 Jupiter masses.They are more massive than the population found by microlensing. So they may be a different population with the different formation process, either similar with that of stars and brown dwarfs, or formed in proto-planetary disks and subsequently scattered into unbound or very distant orbits. It is important to fill the gap of these mass ranges to fully understand these populations. The Wide Field Infrared Survey Telescope (WFIRST) is the highest ranked recommendation for a large space mission in the recent New Worlds, New Horizons (NWNH) in Astronomy and Astrophysics 2010 Decadal Survey. Exoplanet microlensing program is one of the primary science of WFIRST. WFIRST will find about 3000 bound planets and 2000 unbound planets by the high precision continuous survey 15 min

  1. The nuclear techniques in function of improving the efficiency of the flocculators and floats in the industrial waste treatment station of PETROBRAS

    International Nuclear Information System (INIS)

    Damera Martinez, Arnaldo; Ramos Espinosa, Kenia A.; Pinto, Amenonia Ferreira; Barbalho, Andrea de Magalhaes; Derivet Zarzabal, Milagros

    2001-01-01

    This work was carried out in the Station of Treatment of Industrial Waste (STIW) in PETROBRAS (Brazil). The STIW has the function of receiving, to treat and storage liquid wastes coming from diverse points of the refinery, avoiding the environment contamination. This study consists on the determination of the time of residence inside the flocculators and floats, by means of nuclear technique of radioactive tracer, using Tc-99m. This technique has a great economic and environmental importance because the time of residence obtained experimentally in the flocculators and the floats, can be compared with those obtained theoretically, which allow to influence on the system, optimizing its operation

  2. Application of partially diabatic divided wall column to floating liquefied natural gas plant

    International Nuclear Information System (INIS)

    Kim, Young Han

    2014-01-01

    The offshore operation of chemical plant requires the compactness of process equipments due to its harsh environment. A DWC (divided wall column), a compact ternary separator, is a good candidate for distillation process in the offshore operation. In this study the DWC is applied to the offshore FLNG (floating liquefied natural gas) plant, but high utility cost is required in the application because of the large difference of boiling points among feed components. A partially diabatic DWC is proposed for the reduction of the operating cost here, and its design procedure is presented along with performance and economic evaluations and the examination of thermodynamic efficiency as well. The heating duty of the proposed DWC including tray heat transfer is 35% less than that of the conventional system, and the cooling duty is 18% less. The evaluation indicates that some 16% less utility cost is used in the DWC compared with the conventional system, though 7% more investment is required. The exergy loss is reduced by 12%, and the thermodynamic efficiency is improved by 3.3 percentage point over the conventional system. - Highlights: • Diabatic divided wall column for FLNG (floating liquefied natural gas) plant. • Compact column for offshore operation. • 35% less heating duty required. • 16% lower utility necessary. • Exergy loss reduced by 12%

  3. Estimation Trajectory of the Low-Frequency Floating Car Considering the Traffic Control

    Directory of Open Access Journals (Sweden)

    Zhijian Wang

    2013-01-01

    Full Text Available Floating car equipped with GPS to detect traffic flow has been widely used in ITS research and applications. The trajectory estimation is the most critical and complex part in the floating vehicle information processing system. However, the trajectory estimation would be more difficult when using the low-frequency data sampling because of the high communication cost and the numerous data. Specifically, the ordinary algorithm cannot determine the specific vehicle paths with two anchor points across multiple intersections. Considering the accuracy in map matching, this paper used a delay matching algorithm and studied the trajectory estimation algorithm focusing on the issue of existence of a small road network between two anchor points. A method considering the three multiobjective factors of signal control and driving distance and number of intersections was developed. Firstly, an optimal solution set was acquired according to multiobjective decision theory and Pareto optimal principles in game theory. Then, the optimal solution set was evaluated synthetically based on the fuzzy set theory. Finally, the candidate trajectory which is the core evaluation factor was identified as the best possible travel path. The algorithm was validated by using the real traffic data in Wangjing area of Beijing. The results showed that the algorithm can get a better trajectory estimation and provide more traffic information to traffic management department.

  4. Some aspects of arctic offshore floating structures

    Energy Technology Data Exchange (ETDEWEB)

    Lubbad, Raed Khalil

    2011-01-15

    The present work highlights some aspects related to the analyses of Arctic offshore floating structures. This thesis consists of five papers, which can be divided into two main categories. One category deals with the dynamics of slender structures with an emphasis on the prediction and suppression of vortex induced vibrations (VIV), and the other category examines the process of interaction between sloping structures and sea ice with focus on developing a numerical model to simulate this process in real time. Slender structures, such as mooring lines and marine risers, are very important for the offshore petroleum industry, which is currently approaching deeper waters. Increasingly, attention has been focused on predicting the susceptibility of these structures to VIV. In this thesis, two asymptotic techniques namely, the local analysis and the WKB methods, were used to derive closed-form solutions for the natural frequencies and mode shapes of slender line-like structures. Both the top-tensioned nearly-vertical configuration and the catenary configuration were considered. The accuracy of the solutions derived was established through comparison with other analytic solution techniques and with results of numerical finite element solutions. The effects of the bending stiffness and the effects of approximating the tension variation as a linear function were discussed. Experimental data on the multi-modal in-line and cross-flow response behaviour of a towed catenary model were analysed to examine the usefulness of the solutions for predicting the response frequencies and envelopes due to VIV. Helical strakes are often used as a mitigating measure to suppress the VIV of slender structures. This thesis presented an innovative method to fit ropes helically to a riser in the installation phase. Such a procedure will help to overcome the handling problem associated with the use of conventional sharp-edged strakes. Experimental investigations were then performed to verify

  5. Research of design challenges and new technologies for floating LNG

    Directory of Open Access Journals (Sweden)

    Dong-Hyun Lee

    2014-06-01

    Full Text Available With the rate of worldwide LNG demand expected to grow faster than that of gas demand, most major oil companies are currently investing their resources to develop floating LNG-FLNG (i.e. LNG FSRU and LNG FPSO. The global Floating LNG (FLNG market trend will be reviewed based on demand and supply chain relationships. Typical technical issues associated with FLNG design are categorized in terms of global performance evaluation. Although many proven technologies developed through LNG carrier and oil FPSO projects are available for FLNG design, we are still faced with several technical challenges to clear for successful FLNG projects. In this study, some of the challenges encountered during development of the floating LNG facility (i.e. LNG FPSO and FSRU will be reviewed together with their investigated solution. At the same time, research of new LNG-related technologies such as combined containment system will be presented.

  6. Floating cultivation of marine cyanobacteria using coal fly ash.

    Science.gov (United States)

    Matsumoto, M; Yoshida, E; Takeyama, H; Matsunaga, T

    2000-01-01

    The aim of this study was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. We have investigated the viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine micro-algae. The marine cyanobacterium Synechococcus sp. NKBG 040607 was found to adhere to floating CFA blocks in liquid culture medium. Maximum density of attached cells of 2.0 x 10(8) cells/cm2 was achieved using seawater. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks.

  7. Mathematical modeling of large floating roof reservoir temperature arena

    Directory of Open Access Journals (Sweden)

    Liu Yang

    2018-03-01

    Full Text Available The current study is a simplification of related components of large floating roof tank and modeling for three dimensional temperature field of large floating roof tank. The heat transfer involves its transfer between the hot fluid in the oil tank, between the hot fluid and the tank wall and between the tank wall and the external environment. The mathematical model of heat transfer and flow of oil in the tank simulates the temperature field of oil in tank. Oil temperature field of large floating roof tank is obtained by numerical simulation, map the curve of central temperature dynamics with time and analyze axial and radial temperature of storage tank. It determines the distribution of low temperature storage tank location based on the thickness of the reservoir temperature. Finally, it compared the calculated results and the field test data; eventually validated the calculated results based on the experimental results.

  8. Numerical modelling of floating debris in the world's oceans.

    Science.gov (United States)

    Lebreton, L C-M; Greer, S D; Borrero, J C

    2012-03-01

    A global ocean circulation model is coupled to a Lagrangian particle tracking model to simulate 30 years of input, transport and accumulation of floating debris in the world ocean. Using both terrestrial and maritime inputs, the modelling results clearly show the formation of five accumulation zones in the subtropical latitudes of the major ocean basins. The relative size and concentration of each clearly illustrate the dominance of the accumulation zones in the northern hemisphere, while smaller seas surrounded by densely populated areas are also shown to have a high concentration of floating debris. We also determine the relative contribution of different source regions to the total amount of material in a particular accumulation zone. This study provides a framework for describing the transport, distribution and accumulation of floating marine debris and can be continuously updated and adapted to assess scenarios reflecting changes in the production and disposal of plastic worldwide. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Formulation and evaluation of glipizide floating-bioadhesive tablets

    Directory of Open Access Journals (Sweden)

    Jayvadan K. Patel

    2010-10-01

    Full Text Available The purpose of this study was formulation and in vitro evaluation of floating-bioadhesive tablets to lengthen the stay of glipizide in its absorption area. Effervescent tablets were made using chitosan (CH, hydroxypropyl methylcellulose (HPMC, carbopolP934 (CP, polymethacrylic acid (PMA, citric acid, and sodium bicarbonate. Tablets with 5% effervescent base had longer lag time than 10%. The type of polymer had no significant effect on the floating lag time. All tablets floated atop the medium for 23-24 hr. Increasing carbopolP934 caused higher bioadhesion than chitosan (p < 0.05. All formulations showed a Higuchi, non-Fickian release mechanism. Tablets with 10% effervescent base, 80% CH/20% HPMC, or 80% CP/20% PMA seemed desirable.

  10. Investigation of Tank 241-AN-101 Floating Solids

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, Douglas P. [Washington River Protection Solutions, LLC, Richland, VA (United States); Meznarich, H. K. [Washington River Protection Solutions, LLC, Richland, VA (United States)

    2017-10-30

    Tank 241-AN-101 is the receiver tank for retrieval of several C-Farms waste tanks, including Tanks 241-C-102 and 241-C-111. Tank 241 C 111 received first-cycle decontamination waste from the bismuth phosphate process and Plutonium and Uranium Extraction cladding waste, as well as hydraulic fluid. Three grab samples, 1AN-16-01, 1AN-16-01A, and 1AN-16-01B, were collected at the surface of Tank 241-AN-101 on April 25, 2016, after Tank 241-C-111 retrieval was completed. Floating solids were observed in the three grab samples in the 11A hot cell after the samples were received at the 222-S Laboratory. Routine chemical analyses, solid phase characterization on the floating and settled solids, semivolatile organic analysis mainly on the aqueous phase for identification of degradation products of hydraulic fluids were performed. Investigation of the floating solids is reported.

  11. Optimal Control of a Ballast-Stabilized Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Knudsen, Torben; Bak, Thomas

    2011-01-01

    Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. The use of floating structures for deeper waters is being explored. The control objective is a tradeoff between power capture and fatigue, especially that produced by the oscillations caused by the reduced...... structural stiffness of a floating installation in combination with a coupling between the fore–aft motion of the tower and the blade pitch. To address this problem, the present paper models a ballast-stabilized floating wind turbine, and suggests a linear quadratic regulator (LQR) in combination with a wind...... estimator and a state observer. The results are simulated using aero elastic code and analysed in terms of damage equivalent loads. When compared to a baseline controller, this controller clearly demonstrates better generator speed and power tracking while reducing fatigue loads....

  12. Assessment of the nutrient removal effectiveness of floating treatment wetlands applied to urban retention ponds.

    Science.gov (United States)

    Wang, Chih-Yu; Sample, David J

    2014-05-01

    The application of floating treatment wetlands (FTWs) in point and non-point source pollution control has received much attention recently. Although the potential of this emerging technology is supported by various studies, quantifying FTW performance in urban retention ponds remains elusive due to significant research gaps. Actual urban retention pond water was utilized in this mesocosm study to evaluate phosphorus and nitrogen removal efficiency of FTWs. Multiple treatments were used to investigate the contribution of each component in the FTW system with a seven-day retention time. The four treatments included a control, floating mat, pickerelweed (Pontederia cordata L.), and softstem bulrush (Schoenoplectus tabernaemontani). The water samples collected on Day 0 (initial) and 7 were analyzed for total phosphorus (TP), total particulate phosphorus, orthophosphate, total nitrogen (TN), organic nitrogen, ammonia nitrogen, nitrate-nitrite nitrogen, and chlorophyll-a. Statistical tests were used to evaluate the differences between the four treatments. The effects of temperature on TP and TN removal rates of the FTWs were described by the modified Arrhenius equation. Our results indicated that all three FTW designs, planted and unplanted floating mats, could significantly improve phosphorus and nitrogen removal efficiency (%, E-TP and E-TN) compared to the control treatment during the growing season, i.e., May through August. The E-TP and E-TN was enhanced by 8.2% and 18.2% in the FTW treatments planted with the pickerelweed and softstem bulrush, respectively. Organic matter decomposition was likely to be the primary contributor of nutrient removal by FTWs in urban retention ponds. Such a mechanism is fostered by microbes within the attached biofilms on the floating mats and plant root surfaces. Among the results of the four treatments, the FTWs planted with pickerelweed had the highest E-TP, and behaved similarly with the other two FTW treatments for nitrogen removal

  13. Aerodynamics and Motion Performance of the H-Type Floating Vertical Axis Wind Turbine

    Directory of Open Access Journals (Sweden)

    Ying Guo

    2018-02-01

    Full Text Available Aerodynamics and motion performance of the floating vertical wind turbine (VAWT were studied in this paper, where the wind turbine was H-type and the floating foundation was truss spar type. Based on the double-multiple-stream-tube theory, the formulae were deduced to calculate the aerodynamic loads acting on the wind turbine considering the motions of the floating foundation. The surge-heave-pitch nonlinear coupling equations of the H-type floating VAWT were established. Aerodynamics and motion performance of a 5 MW H-type floating VAWT was studied, and the effect of the floating foundation motions on the aerodynamic loads was analyzed. It is shown that the motions of the floating foundation on the aerodynamics cannot be ignored. The motion of the H-type floating VAWT was also compared with that of the Φ-type floating VAWT: they have the same floating foundation, rated output power, mooring system and total displacement. The results show that the H-type floating VAWT has better motion performance, and the mean values of surge, heave and pitch of the H-type floating VAWT are much smaller comparing with the Φ-type floating VAWT.

  14. Capture of free-floating planets by planetary systems

    Science.gov (United States)

    Goulinski, Nadav; Ribak, Erez N.

    2018-01-01

    Evidence of exoplanets with orbits that are misaligned with the spin of the host star may suggest that not all bound planets were born in the protoplanetary disc of their current planetary system. Observations have shown that free-floating Jupiter-mass objects can exceed the number of stars in our Galaxy, implying that capture scenarios may not be so rare. To address this issue, we construct a three-dimensional simulation of a three-body scattering between a free-floating planet and a star accompanied by a Jupiter-mass bound planet. We distinguish between three different possible scattering outcomes, where the free-floating planet may get weakly captured after the brief interaction with the binary, remain unbound or 'kick out' the bound planet and replace it. The simulation was performed for different masses of the free-floating planets and stars, as well as different impact parameters, inclination angles and approach velocities. The outcome statistics are used to construct an analytical approximation of the cross-section for capturing a free-floating planet by fitting their dependence on the tested variables. The analytically approximated cross-section is used to predict the capture rate for these kinds of objects, and to estimate that about 1 per cent of all stars are expected to experience a temporary capture of a free-floating planet during their lifetime. Finally, we propose additional physical processes that may increase the capture statistics and whose contribution should be considered in future simulations in order to determine the fate of the temporarily captured planets.

  15. 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...

  16. Towards the generation of random bits at terahertz rates based on a chaotic semiconductor laser

    International Nuclear Information System (INIS)

    Kanter, Ido; Aviad, Yaara; Reidler, Igor; Cohen, Elad; Rosenbluh, Michael

    2010-01-01

    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.

  17. Towards the generation of random bits at terahertz rates based on a chaotic semiconductor laser

    Science.gov (United States)

    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.

  18. 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....

  19. On algorithmic equivalence of instruction sequences for computing bit string functions

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2015-01-01

    Every partial function from bit strings of a given length to bit strings of a possibly different given length can be computed by a finite instruction sequence that contains only instructions to set and get the content of Boolean registers, forward jump instructions, and a termination instruction. We

  20. On algorithmic equivalence of instruction sequences for computing bit string functions

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2014-01-01

    Every partial function from bit strings of a given length to bit strings of a possibly different given length can be computed by a finite instruction sequence that contains only instructions to set and get the content of Boolean registers, forward jump instructions, and a termination instruction. We

  1. 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...

  2. Possibility, impossibility, and cheat sensitivity of quantum-bit string commitment

    NARCIS (Netherlands)

    Buhrman, H.; Christandl, M.; Hayden, P.; Lo, H.-K.; Wehner, S.

    2008-01-01

    Unconditionally secure nonrelativistic bit commitment is known to be impossible in both the classical and the quantum worlds. But when committing to a string of n bits at once, how far can we stretch the quantum limits? In this paper, we introduce a framework for quantum schemes where Alice commits

  3. 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....

  4. On the prediction of hydroelastic behaviors of a huge floating structure in waves. 2nd Report; Choogata futai no harochu dansei kyodo no suiteiho ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Murai, M.; Kagemoto, H.; Fujino, M. [The University of Tokyo, Tokyo (Japan)

    1997-08-01

    On the hydroelastic behaviors of a huge floating structure, a mutual interaction theory based on the area division method is used for the analysis of a fluid problem and a mode analysis method is used for the analysis of deformation. On the continuous deformation of a floating structure, the structure is considered as a set of partial structures obtained when the plane shape was divided into squares and discretely handled as a series of rigid motions in the small partial structures obtained by dividing the partial structures more finely. The experimental result in a water tank and the distribution method at a singular point were compared on the deformation of the elastic floating structure estimated by calculation based on this formulation. The result showed that the estimation method on the hydroelastic problem proposed in this paper is valid. On the prediction of hydroelastic behaviors of a huge floating structure, various calculation examples indicate that the hydroelastic behavior is not only the relation between the structure length and wavelength, but also that the bending rigidity of a structure is a very important factor. For a huge floating structure in the 5,000 m class, up to shorter wavelength of about {lambda}/L = 1/100 must be investigated. 6 refs., 14 figs., 5 tabs.

  5. Floating electrode microelectromechanical system capacitive switches: A different actuation mechanism

    Science.gov (United States)

    Papaioannou, G.; Giacomozzi, F.; Papandreou, E.; Margesin, B.

    2011-08-01

    The paper investigates the actuation mechanism in floating electrode microelectromechanical system capacitive switches. It is demonstrated that in the pull-in state, the device operation turns from voltage to current controlled actuation. The current arises from Poole-Frenkel mechanism in the dielectric film and Fowler-Nordheim in the bridge-floating electrode air gap. The pull-out voltage seems to arise from the abrupt decrease of Fowler-Nordheim electric field intensity. This mechanism seems to be responsible for the very small difference with respect to the pull-in voltage.

  6. Floating natural gas processing plants. Technical ideal or feasible technology

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, H

    1977-04-01

    Realizability of floating natural gas processing plants is decisively influenced by the economy of the system. Illustrated by the example of the natural gas product LPG (liquefied petroleum gas), a model cost calculation is carried out. It is demonstrated that the increase in the price level during the 1973/1974 energy crisis is an important factor for the realiability in terms of economy of such complicated technical systems. Another aspect which the model calculation revealed is that the economy of floating natural gas processing plants and storage systems can only be estimated in connection with other system components.

  7. Development of floating production systems for the new era

    International Nuclear Information System (INIS)

    Wennesland, J.M.

    1995-01-01

    Maritime Group will give a presentation of present and future trends within the floating production area. Based on the successful operation of Petrojarl 1 (Tentech 885) and now lately the Gryphon A (Tentech 850 C) operated by Kerr McGee a number of floating production systems are now under construction/design for North Sea applications. A status of three developments will be given with emphasize on field development scenarios and market opportunities for the vessels. Based on these on-going projects a discussion of future development trends and possibilities will be presented with special attention to making smaller North-Sea oil fields economically profitable

  8. Warped Discrete Cosine Transform-Based Low Bit-Rate Block Coding Using Image Downsampling

    Directory of Open Access Journals (Sweden)

    Ertürk Sarp

    2007-01-01

    Full Text Available This paper presents warped discrete cosine transform (WDCT-based low bit-rate block coding using image downsampling. While WDCT aims to improve the performance of conventional DCT by frequency warping, the WDCT has only been applicable to high bit-rate coding applications because of the overhead required to define the parameters of the warping filter. Recently, low bit-rate block coding based on image downsampling prior to block coding followed by upsampling after the decoding process is proposed to improve the compression performance for low bit-rate block coders. This paper demonstrates that a superior performance can be achieved if WDCT is used in conjunction with image downsampling-based block coding for low bit-rate applications.

  9. Changes realized from extended bit-depth and metal artifact reduction in CT

    Energy Technology Data Exchange (ETDEWEB)

    Glide-Hurst, C.; Chen, D.; Zhong, H.; Chetty, I. J. [Department of Radiation Oncology, Henry Ford Health Systems, Detroit, Michigan 48202 (United States)

    2013-06-15

    Purpose: High-Z material in computed tomography (CT) yields metal artifacts that degrade image quality and may cause substantial errors in dose calculation. This study couples a metal artifact reduction (MAR) algorithm with enhanced 16-bit depth (vs standard 12-bit) to quantify potential gains in image quality and dosimetry. Methods: Extended CT to electron density (CT-ED) curves were derived from a tissue characterization phantom with titanium and stainless steel inserts scanned at 90-140 kVp for 12- and 16-bit reconstructions. MAR was applied to sinogram data (Brilliance BigBore CT scanner, Philips Healthcare, v.3.5). Monte Carlo simulation (MC-SIM) was performed on a simulated double hip prostheses case (Cerrobend rods embedded in a pelvic phantom) using BEAMnrc/Dosxyz (400 000 0000 histories, 6X, 10 Multiplication-Sign 10 cm{sup 2} beam traversing Cerrobend rod). A phantom study was also conducted using a stainless steel rod embedded in solid water, and dosimetric verification was performed with Gafchromic film analysis (absolute difference and gamma analysis, 2% dose and 2 mm distance to agreement) for plans calculated with Anisotropic Analytic Algorithm (AAA, Eclipse v11.0) to elucidate changes between 12- and 16-bit data. Three patients (bony metastases to the femur and humerus, and a prostate cancer case) with metal implants were reconstructed using both bit depths, with dose calculated using AAA and derived CT-ED curves. Planar dose distributions were assessed via matrix analyses and using gamma criteria of 2%/2 mm. Results: For 12-bit images, CT numbers for titanium and stainless steel saturated at 3071 Hounsfield units (HU), whereas for 16-bit depth, mean CT numbers were much larger (e.g., titanium and stainless steel yielded HU of 8066.5 {+-} 56.6 and 13 588.5 {+-} 198.8 for 16-bit uncorrected scans at 120 kVp, respectively). MC-SIM was well-matched between 12- and 16-bit images except downstream of the Cerrobend rod, where 16-bit dose was {approx}6

  10. Case histories of roller cone core bit application in crystalline rock

    International Nuclear Information System (INIS)

    Dahlem, J.S.

    1988-01-01

    The increased interest in deep crystalline rock drilling projects has resulted in a requirement for premium coring bits which are effective in such a harsh and abrasive environment. Hard formation roller cone insert bits have traditionally and constantly performed well in crystalline rock. As a result, the application of state of the art roller cone rock bit technology to the design and development of core bits has made crystalline coring projects more viable than ever before. This paper follows the development of roller cone core bits by examining their use on project such as HDR (Hot Dry Rock, Los Alamos); NAGRA (Nuclear Waste Disposal Wells in Switzerland); Camborne School of Mines Geothermal Project in Cornwall, UK; Deep Gas Project in Sweden; and the KTB Deep Drilling Project in West Germany

  11. New roller cone bits with unique nozzle designs reduce drilling costs

    International Nuclear Information System (INIS)

    Moffitt, S.R.; Pearce, D.E.; Ivie, C.R.

    1992-01-01

    This paper reports that selection of the optimum rock bit design to achieve the lowest drilling cost in a given application is often difficult due to a large number of rock bit performance considerations. However, in a majority of applications increased penetration rate is the key consideration in reducing drilling costs. Discovery of a new bit design concept has led to the development of roller cone bits that achieve significant penetration rate increases using superior hydraulic nozzle designs. Prototype designs have achieved 20 to 40% increases in penetration rate with comparable footage drilled when tested in 6 1/2, 8 1/2, 8-3/4, 9-7/8 and 12 1/4 IADC 437, 517 and 537 type bits in the U.S., North Sea, Italy, and Oman. Second-generation designs tested in a full-scale drilling laboratory have delivered 70% increases in penetration rates

  12. Simple proof of the impossibility of bit commitment in generalized probabilistic theories using cone programming

    Science.gov (United States)

    Sikora, Jamie; Selby, John

    2018-04-01

    Bit commitment is a fundamental cryptographic task, in which Alice commits a bit to Bob such that she cannot later change the value of the bit, while, simultaneously, the bit is hidden from Bob. It is known that ideal bit commitment is impossible within quantum theory. In this work, we show that it is also impossible in generalized probabilistic theories (under a small set of assumptions) by presenting a quantitative trade-off between Alice's and Bob's cheating probabilities. Our proof relies crucially on a formulation of cheating strategies as cone programs, a natural generalization of semidefinite programs. In fact, using the generality of this technique, we prove that this result holds for the more general task of integer commitment.

  13. Fixed Points

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 5. Fixed Points - From Russia with Love - A Primer of Fixed Point Theory. A K Vijaykumar. Book Review Volume 5 Issue 5 May 2000 pp 101-102. Fulltext. Click here to view fulltext PDF. Permanent link:

  14. Tipping Point

    Medline Plus

    Full Text Available ... OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point ... 24 hours a day. For young children whose home is a playground, it’s the best way to ...

  15. Tipping Point

    Medline Plus

    Full Text Available ... 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ...

  16. A CAMAC display module for fast bit-mapped graphics

    International Nuclear Information System (INIS)

    Abdel-Aal, R.E.

    1992-01-01

    In many data acquisition and analysis facilities for nuclear physics research, utilities for the display of two-dimensional (2D) images and spectra on graphics terminals suffer from low speed, poor resolution, and limit accuracy. Developed of CAMAC bit-mapped graphics modules for this purpose has been discouraged in the past by the large device count needed and the long times required to load the image data from the host computer into the CAMAC hardware; particularly since many such facilities have been designed to support fast DMA block transfers only for data acquisition into the host. This paper describes the design and implementation of a prototype CAMAC graphics display module with a resolution of 256x256 pixels at eight colours for which all components can be easily accommodated in a single-width package. Employed is a hardware technique which reduces the number of programmed CAMAC data transfer operations needed for writing 2D images into the display memory by approximately an order of magnitude, with attendant improvements in the display speed and CPU time consumption. Hardware and software details are given together with sample results. Information on the performance of the module in a typical VAX/MBD data acquisition environment is presented, including data on the mutual effects of simultaneous data acquisition traffic. Suggestions are made for further improvements in performance. (orig.)

  17. Bit Level Synchronized MAC Protocol for Multireader RFID Networks

    Directory of Open Access Journals (Sweden)

    Namboodiri Vinod

    2010-01-01

    Full Text Available The operation of multiple RFID readers in close proximity results in interference between the readers. This issue is termed the reader collision problem and cannot always be solved by assigning them to different frequency channels due to technical and regulatory limitations. The typical solution is to separate the operation of such readers across time. This sequential operation, however, results in a long delay to identify all tags. We present a bit level synchronized (BLSync MAC protocol for multi-reader RFID networks that allows multiple readers to operate simultaneously on the same frequency channel. The BLSync protocol solves the reader collision problem by allowing all readers to transmit the same query at the same time. We analyze the performance of using the BLSync protocol and demonstrate benefits of 40%–50% in terms of tag reading delay for most settings. The benefits of BLSync, first demonstrated through analysis, are then validated and quantified through simulations on realistic reader-tag layouts.

  18. Constellation labeling optimization for bit-interleaved coded APSK

    Science.gov (United States)

    Xiang, Xingyu; Mo, Zijian; Wang, Zhonghai; Pham, Khanh; Blasch, Erik; Chen, Genshe

    2016-05-01

    This paper investigates the constellation and mapping optimization for amplitude phase shift keying (APSK) modulation, which is deployed in Digital Video Broadcasting Satellite - Second Generation (DVB-S2) and Digital Video Broadcasting - Satellite services to Handhelds (DVB-SH) broadcasting standards due to its merits of power and spectral efficiency together with the robustness against nonlinear distortion. The mapping optimization is performed for 32-APSK according to combined cost functions related to Euclidean distance and mutual information. A Binary switching algorithm and its modified version are used to minimize the cost function and the estimated error between the original and received data. The optimized constellation mapping is tested by combining DVB-S2 standard Low-Density Parity-Check (LDPC) codes in both Bit-Interleaved Coded Modulation (BICM) and BICM with iterative decoding (BICM-ID) systems. The simulated results validate the proposed constellation labeling optimization scheme which yields better performance against conventional 32-APSK constellation defined in DVB-S2 standard.

  19. Hill Cipher and Least Significant Bit for Image Messaging Security

    Directory of Open Access Journals (Sweden)

    Muhammad Husnul Arif

    2016-02-01

    Full Text Available Exchange of information through cyberspace has many benefits as an example fast estimated time, unlimited physical distance and space limits, etc. But in these activities can also pose a security risk for confidential information. It is necessary for the safety that can be used to protect data transmitted through the Internet. Encryption algorithm that used to encrypt message to be sent (plaintext into messages that have been randomized (ciphertext is cryptography and steganography algorithms. In application of cryptographic techniques that will be used is Hill Cipher. The technique is combined with steganography techniques Least Significant Bit. The result of merging techniques can maintain the confidentiality of messages because people who do not know the secret key used will be difficult to get the message contained in the stego-image and the image that has been inserted can not be used as a cover image. Message successfully inserted and extracted back on all samples with a good image formats * .bmp, * .png , * .jpg at a resolution of 512 x 512 pixels , 256 x 256 pixels. MSE and PSNR results are not influenced file format or file size, but influenced by dimensions of image. The larger dimensions of the image, then the smaller MSE that means error of image gets smaller.

  20. Transforming networking within the ESIP Federation using ResearchBit

    Science.gov (United States)

    Robinson, E.

    2015-12-01

    Geoscientists increasingly need interdisciplinary teams to solve their research problems. Currently, geoscientists use Research Networking (RN) systems to connect with each other and find people of similar and dissimilar interests. As we shift to digitally mediated scholarship, we need innovative methods for scholarly communication. Formal methods for scholarly communication are undergoing vast transformation owing to the open-access movement and reproducible research. However, informal scholarly communication that takes place at professional society meetings and conferences, like AGU, has received limited research attention relying primarily on serendipitous interaction. The ResearchBit project aims to fundamentally improve informal methods of scholarly communication by leveraging the serendipitous interactions of researchers and making them more aware of co-located potential collaborators with mutual interests. This presentation will describe our preliminary hardware testing done at the Federation for Earth Science Information Partners (ESIP) Summer meeting this past July and the initial recommendation system design. The presentation will also cover the cultural shifts and hurdles to introducing new technology, the privacy concerns of tracking technology and how we are addressing those new issues.

  1. A short impossibility proof of quantum bit commitment

    Energy Technology Data Exchange (ETDEWEB)

    Chiribella, Giulio, E-mail: gchiribella@mail.tsinghua.edu.cn [Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University (China); D' Ariano, Giacomo Mauro, E-mail: dariano@unipv.it [QUIT group, Dipartimento di Fisica, via Bassi 6, 27100 Pavia (Italy); INFN Gruppo IV, Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Perinotti, Paolo, E-mail: paolo.perinotti@unipv.it [QUIT group, Dipartimento di Fisica, via Bassi 6, 27100 Pavia (Italy); INFN Gruppo IV, Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Schlingemann, Dirk, E-mail: d.schlingemann@tu-bs.de [ISI Foundation, Quantum Information Theory Unit, Viale S. Severo 65, 10133 Torino (Italy); Werner, Reinhard, E-mail: Reinhard.Werner@itp.uni-hannover.de [Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover (Germany)

    2013-06-17

    Bit commitment protocols, whose security is based on the laws of quantum mechanics alone, are generally held to be impossible on the basis of a concealment–bindingness tradeoff (Lo and Chau, 1997 [1], Mayers, 1997 [2]). A strengthened and explicit impossibility proof has been given in D'Ariano et al. (2007) [3] in the Heisenberg picture and in a C{sup ⁎}-algebraic framework, considering all conceivable protocols in which both classical and quantum information is exchanged. In the present Letter we provide a new impossibility proof in the Schrödinger picture, greatly simplifying the classification of protocols and strategies using the mathematical formulation in terms of quantum combs (Chiribella et al., 2008 [4]), with each single-party strategy represented by a conditioned comb. We prove that assuming a stronger notion of concealment—for each classical communication history, not in average—allows Alice's cheat to pass also the worst-case Bob's test. The present approach allows us to restate the concealment–bindingness tradeoff in terms of the continuity of dilations of probabilistic quantum combs with the metric given by the comb discriminability-distance.

  2. 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.

  3. A short impossibility proof of quantum bit commitment

    International Nuclear Information System (INIS)

    Chiribella, Giulio; D'Ariano, Giacomo Mauro; Perinotti, Paolo; Schlingemann, Dirk; Werner, Reinhard

    2013-01-01

    Bit commitment protocols, whose security is based on the laws of quantum mechanics alone, are generally held to be impossible on the basis of a concealment–bindingness tradeoff (Lo and Chau, 1997 [1], Mayers, 1997 [2]). A strengthened and explicit impossibility proof has been given in D'Ariano et al. (2007) [3] in the Heisenberg picture and in a C ⁎ -algebraic framework, considering all conceivable protocols in which both classical and quantum information is exchanged. In the present Letter we provide a new impossibility proof in the Schrödinger picture, greatly simplifying the classification of protocols and strategies using the mathematical formulation in terms of quantum combs (Chiribella et al., 2008 [4]), with each single-party strategy represented by a conditioned comb. We prove that assuming a stronger notion of concealment—for each classical communication history, not in average—allows Alice's cheat to pass also the worst-case Bob's test. The present approach allows us to restate the concealment–bindingness tradeoff in terms of the continuity of dilations of probabilistic quantum combs with the metric given by the comb discriminability-distance.

  4. Statistical mechanics approach to 1-bit compressed sensing

    International Nuclear Information System (INIS)

    Xu, Yingying; Kabashima, Yoshiyuki

    2013-01-01

    Compressed sensing is a framework that makes it possible to recover an N-dimensional sparse vector x∈R N from its linear transformation y∈R M of lower dimensionality M 1 -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 l 1 -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. (paper)

  5. High Bit-Depth Medical Image Compression With HEVC.

    Science.gov (United States)

    Parikh, Saurin S; Ruiz, Damian; Kalva, Hari; Fernandez-Escribano, Gerardo; Adzic, Velibor

    2018-03-01

    Efficient storing and retrieval of medical images has direct impact on reducing costs and improving access in cloud-based health care services. JPEG 2000 is currently the commonly used compression format for medical images shared using the DICOM standard. However, new formats such as high efficiency video coding (HEVC) can provide better compression efficiency compared to JPEG 2000. Furthermore, JPEG 2000 is not suitable for efficiently storing image series and 3-D imagery. Using HEVC, a single format can support all forms of medical images. This paper presents the use of HEVC for diagnostically acceptable medical image compression, focusing on compression efficiency compared to JPEG 2000. Diagnostically acceptable lossy compression and complexity of high bit-depth medical image compression are studied. Based on an established medically acceptable compression range for JPEG 2000, this paper establishes acceptable HEVC compression range for medical imaging applications. Experimental results show that using HEVC can increase the compression performance, compared to JPEG 2000, by over 54%. Along with this, a new method for reducing computational complexity of HEVC encoding for medical images is proposed. Results show that HEVC intra encoding complexity can be reduced by over 55% with negligible increase in file size.

  6. A Fast Soft Bit Error Rate Estimation Method

    Directory of Open Access Journals (Sweden)

    Ait-Idir Tarik

    2010-01-01

    Full Text Available We have suggested in a previous publication a method to estimate the Bit Error Rate (BER of a digital communications system instead of using the famous Monte Carlo (MC simulation. This method was based on the estimation of the probability density function (pdf of soft observed samples. The kernel method was used for the pdf estimation. In this paper, we suggest to use a Gaussian Mixture (GM model. The Expectation Maximisation algorithm is used to estimate the parameters of this mixture. The optimal number of Gaussians is computed by using Mutual Information Theory. The analytical expression of the BER is therefore simply given by using the different estimated parameters of the Gaussian Mixture. Simulation results are presented to compare the three mentioned methods: Monte Carlo, Kernel and Gaussian Mixture. We analyze the performance of the proposed BER estimator in the framework of a multiuser code division multiple access system and show that attractive performance is achieved compared with conventional MC or Kernel aided techniques. The results show that the GM method can drastically reduce the needed number of samples to estimate the BER in order to reduce the required simulation run-time, even at very low BER.

  7. Feasibility Study of 8-Bit Microcontroller Applications for Ethernet

    Directory of Open Access Journals (Sweden)

    Lech Gulbinovič

    2011-08-01

    Full Text Available Feasibility study of 8-bit microcontroller applications for Ethernet is presented. Designed device is based on ATmega32 microcontroller and 10 Mbps Ethernet controller ENC28J60. Device is simulated as mass queuing theoretical model with ticket booking counter. Practical explorations are accomplished and characteristics are determined. Practical results are compared to theoretical ones. Program code and device packet processing speed optimization are discussed. Microcontroller packet processing speed and packet latency depend on packet size. For ICMP protocol packet processing speed varies 1.4–2.1 Mbps, latency – 0.8–8.4 ms. UDP protocol packet processing speed varies 1.3–1.8 Mbps, latency – 1.1–9.6 ms. Packet processing speed depends on compilation settings and program code compression level. Best results are reached on optimization le­vel ‑O3, then speed increased ~3% but program code size increased 68% comparing to –Os optimization level.Article in Lithuanian

  8. The response of pile-guided floats subjected to dynamic loading : volume I final report.

    Science.gov (United States)

    2014-08-01

    Pile : - : Guided floats can be a desirable alternative to stationary berthing structures. Both floats and guide piles are subjected to dynamic : forces such as wind generated waves and impacts from vessels. This project developed a rational basis fo...

  9. 14 CFR 23.533 - Hull and main float bottom pressures.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float bottom pressures. 23... Water Loads § 23.533 Hull and main float bottom pressures. (a) General. The hull and main float....00213; K2=hull station weighing factor, in accordance with figure 2 of appendix I of this part; VS1...

  10. 14 CFR 25.533 - Hull and main float bottom pressures.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float bottom pressures. 25... AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Water Loads § 25.533 Hull and main float bottom pressures. (a) General. The hull and main float structure, including frames and bulkheads...

  11. 14 CFR 23.529 - Hull and main float landing conditions.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Hull and main float landing conditions. 23... Water Loads § 23.529 Hull and main float landing conditions. (a) Symmetrical step, bow, and stern... directed perpendicularly to the keel line. (b) Unsymmetrical landing for hull and single float seaplanes...

  12. Floating Collection in an Academic Library: An Audacious Experiment That Succeeded

    Science.gov (United States)

    Coopey, Barbara; Eshbach, Barbara; Notartomas, Trish

    2016-01-01

    Can a floating collection thrive in a large multicampus academic research library? Floating collections have been successful in public libraries for some time, but it is uncommon for academic libraries and unheard of for a large academic library system. This article will discuss the investigation into the feasibility of a floating collection at…

  13. Dew Point

    OpenAIRE

    Goldsmith, Shelly

    1999-01-01

    Dew Point was a solo exhibition originating at PriceWaterhouseCoopers Headquarters Gallery, London, UK and toured to the Centre de Documentacio i Museu Textil, Terrassa, Spain and Gallery Aoyama, Tokyo, Japan.

  14. Tipping Point

    Medline Plus

    Full Text Available ... Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ...

  15. Tipping Point

    Science.gov (United States)

    ... Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ...

  16. Tipping Point

    Medline Plus

    Full Text Available ... Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head ... see news reports about horrible accidents involving young children and furniture, appliance and tv tip-overs. The ...

  17. Tipping Point

    Medline Plus

    Full Text Available ... Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head ... TV falls with about the same force as child falling from the third story of a building. ...

  18. Tipping Point

    Medline Plus

    Full Text Available ... Tipping Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture ... about horrible accidents involving young children and furniture, appliance and tv tip-overs. The force of a ...

  19. Recent Developments in the Construction of Floating Structures ...

    African Journals Online (AJOL)

    This paper presents the applications of floating structures in (a) creating land from the ocean for airports, container ports, cruise terminals, oil storage, power plants, fish farms, recreation facilities, aquatic observatories, residential facilities, marinas and even relay bases for receiving micro waves from outer space, etc, ...

  20. A global inventory of small floating plastic debris

    NARCIS (Netherlands)

    Sebille, van Erik; Wilcox, Chris; Lebreton, Laurent; Maximenko, Nikolai; Hardesty, Britta Denise; Franeker, van J.A.; Eriksen, Marcus; Siegel, David; Galgani, F.; Law, Kara Lavender

    2015-01-01

    Microplastic debris floating at the ocean surface can harm marine life. Understanding the severity of this harm requires knowledge of plastic abundance and distributions. Dozens of expeditions measuring microplastics have been carried out since the 1970s, but they have primarily focused on