Bit Error Rate Performance of a MIMO-CDMA System Employing Parity-Bit-Selected Spreading in Frequency Nonselective Rayleigh Fading

Directory of Open Access Journals (Sweden)

Claude D'Amours

2011-01-01

Full Text Available We analytically derive the upper bound for the bit error rate (BER performance of a single user multiple input multiple output code division multiple access (MIMO-CDMA system employing parity-bit-selected spreading in slowly varying, flat Rayleigh fading. The analysis is done for spatially uncorrelated links. The analysis presented demonstrates that parity-bit-selected spreading provides an asymptotic gain of 10log(Nt dB over conventional MIMO-CDMA when the receiver has perfect channel estimates. This analytical result concurs with previous works where the (BER is determined by simulation methods and provides insight into why the different techniques provide improvement over conventional MIMO-CDMA systems.

Linear transceiver design for nonorthogonal amplify-and-forward protocol using a bit error rate criterion

KAUST Repository

Ahmed, Qasim Zeeshan

2014-04-01

The ever growing demand of higher data rates can now be addressed by exploiting cooperative diversity. This form of diversity has become a fundamental technique for achieving spatial diversity by exploiting the presence of idle users in the network. This has led to new challenges in terms of designing new protocols and detectors for cooperative communications. Among various amplify-and-forward (AF) protocols, the half duplex non-orthogonal amplify-and-forward (NAF) protocol is superior to other AF schemes in terms of error performance and capacity. However, this superiority is achieved at the cost of higher receiver complexity. Furthermore, in order to exploit the full diversity of the system an optimal precoder is required. In this paper, an optimal joint linear transceiver is proposed for the NAF protocol. This transceiver operates on the principles of minimum bit error rate (BER), and is referred as joint bit error rate (JBER) detector. The BER performance of JBER detector is superior to all the proposed linear detectors such as channel inversion, the maximal ratio combining, the biased maximum likelihood detectors, and the minimum mean square error. The proposed transceiver also outperforms previous precoders designed for the NAF protocol. © 2002-2012 IEEE.

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.

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.

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.

Analytical expression for the bit error rate of cascaded all-optical regenerators

DEFF Research Database (Denmark)

Mørk, Jesper; Öhman, Filip; Bischoff, S.

2003-01-01

We derive an approximate analytical expression for the bit error rate of cascaded fiber links containing all-optical 2R-regenerators. A general analysis of the interplay between noise due to amplification and the degree of reshaping (nonlinearity) of the regenerator is performed.......We derive an approximate analytical expression for the bit error rate of cascaded fiber links containing all-optical 2R-regenerators. A general analysis of the interplay between noise due to amplification and the degree of reshaping (nonlinearity) of the regenerator is performed....

Traffic management mechanism for intranets with available-bit-rate access to the Internet

Science.gov (United States)

Hassan, Mahbub; Sirisena, Harsha R.; Atiquzzaman, Mohammed

1997-10-01

The design of a traffic management mechanism for intranets connected to the Internet via an available bit rate access- link is presented. Selection of control parameters for this mechanism for optimum performance is shown through analysis. An estimate for packet loss probability at the access- gateway is derived for random fluctuation of available bit rate of the access-link. Some implementation strategies of this mechanism in the standard intranet protocol stack are also suggested.

Invariance of the bit error rate in the ancilla-assisted homodyne detection

International Nuclear Information System (INIS)

Yoshida, Yuhsuke; Takeoka, Masahiro; Sasaki, Masahide

2010-01-01

We investigate the minimum achievable bit error rate of the discrimination of binary coherent states with the help of arbitrary ancillary states. We adopt homodyne measurement with a common phase of the local oscillator and classical feedforward control. After one ancillary state is measured, its outcome is referred to the preparation of the next ancillary state and the tuning of the next mixing with the signal. It is shown that the minimum bit error rate of the system is invariant under the following operations: feedforward control, deformations, and introduction of any ancillary state. We also discuss the possible generalization of the homodyne detection scheme.

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.

Improving soft FEC performance for higher-order modulations via optimized bit channel mappings.

Science.gov (United States)

Häger, Christian; Amat, Alexandre Graell I; Brännström, Fredrik; Alvarado, Alex; Agrell, Erik

2014-06-16

Soft forward error correction with higher-order modulations is often implemented in practice via the pragmatic bit-interleaved coded modulation paradigm, where a single binary code is mapped to a nonbinary modulation. In this paper, we study the optimization of the mapping of the coded bits to the modulation bits for a polarization-multiplexed fiber-optical system without optical inline dispersion compensation. Our focus is on protograph-based low-density parity-check (LDPC) codes which allow for an efficient hardware implementation, suitable for high-speed optical communications. The optimization is applied to the AR4JA protograph family, and further extended to protograph-based spatially coupled LDPC codes assuming a windowed decoder. Full field simulations via the split-step Fourier method are used to verify the analysis. The results show performance gains of up to 0.25 dB, which translate into a possible extension of the transmission reach by roughly up to 8%, without significantly increasing the system complexity.

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.)

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.

Symbol and Bit Error Rates Analysis of Hybrid PIM-CDMA

Directory of Open Access Journals (Sweden)

Ghassemlooy Z

2005-01-01

Full Text Available A hybrid pulse interval modulation code-division multiple-access (hPIM-CDMA scheme employing the strict optical orthogonal code (SOCC with unity and auto- and cross-correlation constraints for indoor optical wireless communications is proposed. In this paper, we analyse the symbol error rate (SER and bit error rate (BER of hPIM-CDMA. In the analysis, we consider multiple access interference (MAI, self-interference, and the hybrid nature of the hPIM-CDMA signal detection, which is based on the matched filter (MF. It is shown that the BER/SER performance can only be evaluated if the bit resolution conforms to the condition set by the number of consecutive false alarm pulses that might occur and be detected, so that one symbol being divided into two is unlikely to occur. Otherwise, the probability of SER and BER becomes extremely high and indeterminable. We show that for a large number of users, the BER improves when increasing the code weight . The results presented are compared with other modulation schemes.

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

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...

Bit-rate-transparent optical RZ-to-NRZ format conversion based on linear spectral phase filtering

DEFF Research Database (Denmark)

Maram, Reza; Da Ros, Francesco; Guan, Pengyu

2017-01-01

We propose a novel and strikingly simple design for all-optical bit-rate-transparent RZ-to-NRZ conversion based on optical phase filtering. The proposed concept is experimentally validated through format conversion of a 640 Gbit/s coherent RZ signal to NRZ signal.......We propose a novel and strikingly simple design for all-optical bit-rate-transparent RZ-to-NRZ conversion based on optical phase filtering. The proposed concept is experimentally validated through format conversion of a 640 Gbit/s coherent RZ signal to NRZ signal....

Fiber Bragg grating based notch filter for bit-rate-transparent NRZ to PRZ format conversion with two-degree-of-freedom optimization

International Nuclear Information System (INIS)

Cao, Hui; Zuo, Jun; Xiong, Bangyun; Cheng, Jianqun; Shu, Xuewen; Shen, Fangcheng; Liu, Xin; Atai, Javid

2015-01-01

We propose a novel notch-filtering scheme for bit-rate transparent all-optical NRZ-to-PRZ format conversion. The scheme is based on a two-degree-of-freedom optimally designed fiber Bragg grating. It is shown that a notch filter optimized for any specific operating bit rate can be used to realize high-Q-factor format conversion over a wide bit rate range without requiring any tuning. (paper)

Novel relations between the ergodic capacity and the average bit error rate

KAUST Repository

Yilmaz, Ferkan

2011-11-01

Ergodic capacity and average bit error rate have been widely used to compare the performance of different wireless communication systems. As such recent scientific research and studies revealed strong impact of designing and implementing wireless technologies based on these two performance indicators. However and to the best of our knowledge, the direct links between these two performance indicators have not been explicitly proposed in the literature so far. In this paper, we propose novel relations between the ergodic capacity and the average bit error rate of an overall communication system using binary modulation schemes for signaling with a limited bandwidth and operating over generalized fading channels. More specifically, we show that these two performance measures can be represented in terms of each other, without the need to know the exact end-to-end statistical characterization of the communication channel. We validate the correctness and accuracy of our newly proposed relations and illustrated their usefulness by considering some classical examples. © 2011 IEEE.

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...

Performance of the JPEG Estimated Spectrum Adaptive Postfilter (JPEG-ESAP) for Low Bit Rates

Science.gov (United States)

Linares, Irving (Inventor)

2016-01-01

Frequency-based, pixel-adaptive filtering using the JPEG-ESAP algorithm for low bit rate JPEG formatted color images may allow for more compressed images while maintaining equivalent quality at a smaller file size or bitrate. For RGB, an image is decomposed into three color bands--red, green, and blue. The JPEG-ESAP algorithm is then applied to each band (e.g., once for red, once for green, and once for blue) and the output of each application of the algorithm is rebuilt as a single color image. The ESAP algorithm may be repeatedly applied to MPEG-2 video frames to reduce their bit rate by a factor of 2 or 3, while maintaining equivalent video quality, both perceptually, and objectively, as recorded in the computed PSNR values.

100G Flexible IM-DD 850 nm VCSEL Transceiver with Fractional Bit Rate Using Eight-Dimensional PAM

DEFF Research Database (Denmark)

Lu, Xiaofeng; Lyubopytov, Vladimir; Chorchos, Łukasz

2017-01-01

We demonstrate a novel optical transceiver scheme with a net flexible bit rate up to 100Gbit/s with 5 Gbit/s granularity, using an eight-dimensional modulation format family, and investigate its performance on capacity, reach, and power tolerance.......We demonstrate a novel optical transceiver scheme with a net flexible bit rate up to 100Gbit/s with 5 Gbit/s granularity, using an eight-dimensional modulation format family, and investigate its performance on capacity, reach, and power tolerance....

Dynamic detection-rate-based bit allocation with genuine interval concealment for binary biometric representation.

Science.gov (United States)

Lim, Meng-Hui; Teoh, Andrew Beng Jin; Toh, Kar-Ann

2013-06-01

Biometric discretization is a key component in biometric cryptographic key generation. It converts an extracted biometric feature vector into a binary string via typical steps such as segmentation of each feature element into a number of labeled intervals, mapping of each interval-captured feature element onto a binary space, and concatenation of the resulted binary output of all feature elements into a binary string. Currently, the detection rate optimized bit allocation (DROBA) scheme is one of the most effective biometric discretization schemes in terms of its capability to assign binary bits dynamically to user-specific features with respect to their discriminability. However, we learn that DROBA suffers from potential discriminative feature misdetection and underdiscretization in its bit allocation process. This paper highlights such drawbacks and improves upon DROBA based on a novel two-stage algorithm: 1) a dynamic search method to efficiently recapture such misdetected features and to optimize the bit allocation of underdiscretized features and 2) a genuine interval concealment technique to alleviate crucial information leakage resulted from the dynamic search. Improvements in classification accuracy on two popular face data sets vindicate the feasibility of our approach compared with DROBA.

Two-dimensional optoelectronic interconnect-processor and its operational bit error rate

Science.gov (United States)

Liu, J. Jiang; Gollsneider, Brian; Chang, Wayne H.; Carhart, Gary W.; Vorontsov, Mikhail A.; Simonis, George J.; Shoop, Barry L.

2004-10-01

Two-dimensional (2-D) multi-channel 8x8 optical interconnect and processor system were designed and developed using complementary metal-oxide-semiconductor (CMOS) driven 850-nm vertical-cavity surface-emitting laser (VCSEL) arrays and the photodetector (PD) arrays with corresponding wavelengths. We performed operation and bit-error-rate (BER) analysis on this free-space integrated 8x8 VCSEL optical interconnects driven by silicon-on-sapphire (SOS) circuits. Pseudo-random bit stream (PRBS) data sequence was used in operation of the interconnects. Eye diagrams were measured from individual channels and analyzed using a digital oscilloscope at data rates from 155 Mb/s to 1.5 Gb/s. Using a statistical model of Gaussian distribution for the random noise in the transmission, we developed a method to compute the BER instantaneously with the digital eye-diagrams. Direct measurements on this interconnects were also taken on a standard BER tester for verification. We found that the results of two methods were in the same order and within 50% accuracy. The integrated interconnects were investigated in an optoelectronic processing architecture of digital halftoning image processor. Error diffusion networks implemented by the inherently parallel nature of photonics promise to provide high quality digital halftoned images.

Bit rate maximization for multicast LP-OFDM systems in PLC context

OpenAIRE

Maiga , Ali; Baudais , Jean-Yves; Hélard , Jean-François

2009-01-01

ISBN: 978-88-900984-8-2.; International audience; In this paper, we propose a new resource allocation algorithm based on linear precoding technique for multicast OFDM systems. Linear precoding technique applied to OFDM systems has already proved its ability to significantly increase the system throughput in a powerline communication (PLC) context. Simulations through PLC channels show that this algorithm outperforms the classical multicast method (up to 7.3% bit rate gain) and gives better pe...

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...

Performance Analysis for Bit Error Rate of DS- CDMA Sensor Network Systems with Source Coding

Directory of Open Access Journals (Sweden)

Haider M. AlSabbagh

2012-03-01

Full Text Available The minimum energy (ME coding combined with DS-CDMA wireless sensor network is analyzed in order to reduce energy consumed and multiple access interference (MAI with related to number of user(receiver. Also, the minimum energy coding which exploits redundant bits for saving power with utilizing RF link and On-Off-Keying modulation. The relations are presented and discussed for several levels of errors expected in the employed channel via amount of bit error rates and amount of the SNR for number of users (receivers.

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.

Experimental confirmation and physical understanding of ultra-high bit rate impulse radio in the THz digital communication channels of the atmosphere

Science.gov (United States)

Mandehgar, Mahboubeh; Yang, Yihong; Grischkowsky, D.

2014-09-01

We have performed highly accurate numerical calculations of high bit rate impulse propagation through the seven digital communication channels of the atmosphere at RH 58% (10 g m-3). These calculations maximized bit rates for pathlengths equal to or longer than 100 m. We have experimentally verified our calculations for three channels with a propagation pathlength of 137 m and RH 65% (11.2 g m-3). Excellent agreement between measurement and theory was obtained for Channel 3 at 252 GHz, bit rate 84 Gb s-1, FWHM bandwidth (BW) 180 GHz; Channel 6 at 672 GHz, 45 Gb s-1, BW 84 GHz; and Channel 7 at 852 GHz, 56.8 Gb s-1, BW 108 GHz.

Inadvertently programmed bits in Samsung 128 Mbit flash devices: a flaky investigation

Science.gov (United States)

Swift, G.

2002-01-01

JPL's X2000 avionics design pioneers new territory by specifying a non-volatile memory (NVM) board based on flash memories. The Samsung 128Mb device chosen was found to demonstrate bit errors (mostly program disturbs) and block-erase failures that increase with cycling. Low temperature, certain pseudo- random patterns, and, probably, higher bias increase the observable bit errors. An experiment was conducted to determine the wearout dependence of the bit errors to 100k cycles at cold temperature using flight-lot devices (some pre-irradiated). The results show an exponential growth rate, a wide part-to-part variation, and some annealing behavior.

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.

Experimental confirmation and physical understanding of ultra-high bit rate impulse radio in the THz digital communication channels of the atmosphere

International Nuclear Information System (INIS)

Mandehgar, Mahboubeh; Yang, Yihong; Grischkowsky, D

2014-01-01

We have performed highly accurate numerical calculations of high bit rate impulse propagation through the seven digital communication channels of the atmosphere at RH 58% (10 g m −3 ). These calculations maximized bit rates for pathlengths equal to or longer than 100 m. We have experimentally verified our calculations for three channels with a propagation pathlength of 137 m and RH 65% (11.2 g m −3 ). Excellent agreement between measurement and theory was obtained for Channel 3 at 252 GHz, bit rate 84 Gb s −1 , FWHM bandwidth (BW) 180 GHz; Channel 6 at 672 GHz, 45 Gb s −1 , BW 84 GHz; and Channel 7 at 852 GHz, 56.8 Gb s −1 , BW 108 GHz. (special issue article)

Reconfigurable Digital Coherent Receiver for Metro-Access Networks Supporting Mixed Modulation Formats and Bit-rates

DEFF Research Database (Denmark)

Caballero Jambrina, Antonio; Guerrero Gonzalez, Neil; Arlunno, Valeria

2013-01-01

A single, reconfigurable, digital coherent receiver is proposed and experimentally demonstrated for converged wireless and optical fiber transport. The capacity of reconstructing the full transmitted optical field allows for the demodulation of mixed modulation formats and bit-rates. We performed...

Pulse shaping for all-optical signal processing of ultra-high bit rate serial data signals

DEFF Research Database (Denmark)

Palushani, Evarist

The following thesis concerns pulse shaping and optical waveform manipulation for all-optical signal processing of ultra-high bit rate serial data signals, including generation of optical pulses in the femtosecond regime, serial-to-parallel conversion and terabaud coherent optical time division...

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.

Design of pseudo-symmetric high bit rate, bend insensitive optical fiber applicable for high speed FTTH

Science.gov (United States)

Makouei, Somayeh; Koozekanani, Z. D.

2014-12-01

In this paper, with sophisticated modification on modal-field distribution and introducing new design procedure, the single-mode fiber with ultra-low bending-loss and pseudo-symmetric high bit-rate of uplink and downlink, appropriate for fiber-to-the-home (FTTH) operation is presented. The bending-loss reduction and dispersion management are done by the means of Genetic Algorithm. The remarkable feature of this methodology is designing a bend-insensitive fiber without reduction of core radius and MFD. Simulation results show bending loss of 1.27×10-2 dB/turn at 1.55 μm for 5 mm curvature radius. The MFD and Aeff are 9.03 μm and 59.11 μm2. Moreover, the upstream and downstream bit-rates are approximately 2.38 Gbit/s-km and 3.05 Gbit/s-km.

FPGA-based Bit-Error-Rate Tester for SEU-hardened Optical Links

CERN Document Server

Detraz, S; Moreira, P; Papadopoulos, S; Papakonstantinou, I; Seif El Nasr, S; Sigaud, C; Soos, C; Stejskal, P; Troska, J; Versmissen, H

2009-01-01

The next generation of optical links for future High-Energy Physics experiments will require components qualified for use in radiation-hard environments. To cope with radiation induced single-event upsets, the physical layer protocol will include Forward Error Correction (FEC). Bit-Error-Rate (BER) testing is a widely used method to characterize digital transmission systems. In order to measure the BER with and without the proposed FEC, simultaneously on several devices, a multi-channel BER tester has been developed. This paper describes the architecture of the tester, its implementation in a Xilinx Virtex-5 FPGA device and discusses the experimental results.

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.

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.

A bit-rate flexible and power efficient all-optical demultiplexer realised by monolithically integrated Michelson interferometer

DEFF Research Database (Denmark)

Vaa, Michael; Mikkelsen, Benny; Jepsen, Kim Stokholm

1996-01-01

A novel bit-rate flexible and very power efficient all-optical demultiplexer using differential optical control of a monolithically integrated Michelson interferometer with MQW SOAs is demonstrated at 40 to 10 Gbit/s. Gain switched DFB lasers provide ultra stable data and control signals....

Performance analysis for the bit-error rate of SAC-OCDMA systems

Science.gov (United States)

Feng, Gang; Cheng, Wenqing; Chen, Fujun

2015-09-01

Under low power, Gaussian statistics by invoking the central limit theorem is feasible to predict the upper bound in the spectral-amplitude-coding optical code division multiple access (SAC-OCDMA) system. However, this case severely underestimates the bit-error rate (BER) performance of the system under high power assumption. Fortunately, the exact negative binomial (NB) model is a perfect replacement for the Gaussian model in the prediction and evaluation. Based on NB statistics, a more accurate closed-form expression is analyzed and derived for the SAC-OCDMA system. The experiment shows that the obtained expression provides a more precise prediction of the BER performance under the low and high power assumptions.

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.

100G Flexible IM-DD 850 nm VCSEL Transceiver with Fractional Bit Rate Using Eight-Dimensional PAM

DEFF Research Database (Denmark)

Lu, Xiaofeng; Lyubopytov, Vladimir; Chorchos, Łukasz

2017-01-01

We demonstrate a novel optical transceiver scheme with a net flexible bit rate up to 100Gbit/s with 5 Gbit/s granularity, using an eight-dimensional modulation format family, and investigate its performance on capacity, reach, and power tolerance....

A software reconfigurable optical multiband UWB system utilizing a bit-loading combined with adaptive LDPC code rate scheme

Science.gov (United States)

He, Jing; Dai, Min; Chen, Qinghui; Deng, Rui; Xiang, Changqing; Chen, Lin

2017-07-01

In this paper, an effective bit-loading combined with adaptive LDPC code rate algorithm is proposed and investigated in software reconfigurable multiband UWB over fiber system. To compensate the power fading and chromatic dispersion for the high frequency of multiband OFDM UWB signal transmission over standard single mode fiber (SSMF), a Mach-Zehnder modulator (MZM) with negative chirp parameter is utilized. In addition, the negative power penalty of -1 dB for 128 QAM multiband OFDM UWB signal are measured at the hard-decision forward error correction (HD-FEC) limitation of 3.8 × 10-3 after 50 km SSMF transmission. The experimental results show that, compared to the fixed coding scheme with the code rate of 75%, the signal-to-noise (SNR) is improved by 2.79 dB for 128 QAM multiband OFDM UWB system after 100 km SSMF transmission using ALCR algorithm. Moreover, by employing bit-loading combined with ALCR algorithm, the bit error rate (BER) performance of system can be further promoted effectively. The simulation results present that, at the HD-FEC limitation, the value of Q factor is improved by 3.93 dB at the SNR of 19.5 dB over 100 km SSMF transmission, compared to the fixed modulation with uncoded scheme at the same spectrum efficiency (SE).

Comparison of Bit Error Rate of Line Codes in NG-PON2

Directory of Open Access Journals (Sweden)

Tomas Horvath

2016-05-01

Full Text Available This article focuses on simulation and comparison of line codes NRZ (Non Return to Zero, RZ (Return to Zero and Miller’s code for NG-PON2 (Next-Generation Passive Optical Network Stage 2 using. Our article provides solutions with Q-factor, BER (Bit Error Rate, and bandwidth comparison. Line codes are the most important part of communication over the optical fibre. The main role of these codes is digital signal representation. NG-PON2 networks use optical fibres for communication that is the reason why OptSim v5.2 is used for simulation.

Iterative decoding of SOVA and LDPC product code for bit-patterned media recoding

Science.gov (United States)

Jeong, Seongkwon; Lee, Jaejin

2018-05-01

The demand for high-density storage systems has increased due to the exponential growth of data. Bit-patterned media recording (BPMR) is one of the promising technologies to achieve the density of 1Tbit/in2 and higher. To increase the areal density in BPMR, the spacing between islands needs to be reduced, yet this aggravates inter-symbol interference and inter-track interference and degrades the bit error rate performance. In this paper, we propose a decision feedback scheme using low-density parity check (LDPC) product code for BPMR. This scheme can improve the decoding performance using an iterative approach with extrinsic information and log-likelihood ratio value between iterative soft output Viterbi algorithm and LDPC product code. Simulation results show that the proposed LDPC product code can offer 1.8dB and 2.3dB gains over the one LDPC code at the density of 2.5 and 3 Tb/in2, respectively, when bit error rate is 10-6.

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

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.

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

Bits and q-bits as versatility measures

Directory of Open Access Journals (Sweden)

José R.C. Piqueira

2004-06-01

Full Text Available Using Shannon information theory is a common strategy to measure any kind of variability in a signal or phenomenon. Some methods were developed to adapt information entropy measures to bird song data trying to emphasize its versatility aspect. This classical approach, using the concept of bit, produces interesting results. Now, the original idea developed in this paper is to use the quantum information theory and the quantum bit (q-bit concept in order to provide a more complete vision of the experimental results.Usar a teoria da informação de Shannon é uma estratégia comum para medir todo tipo de variabilidade em um sinal ou fenômeno. Alguns métodos foram desenvolvidos para adaptar a medida de entropia informacional a dados de cantos de pássaro, tentando enfatizar seus aspectos de versatilidade. Essa abordagem clássica, usando o conceito de bit, produz resultados interessantes. Agora, a idéia original desenvolvida neste artigo é usar a teoria quântica da informação e o conceito de q-bit, com a finalidade de proporcionar uma visão mais completa dos resultados experimentais.

A minimum bit error-rate detector for amplify and forward relaying systems

KAUST Repository

Ahmed, Qasim Zeeshan; Alouini, Mohamed-Slim; Aissa, Sonia

2012-01-01

In this paper, a new detector is being proposed for amplify-and-forward (AF) relaying system when communicating with the assistance of L number of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the system. The complexity of the system is further reduced by implementing this detector adaptively. The proposed detector is free from channel estimation. Our results demonstrate that the proposed detector is capable of achieving a gain of more than 1-dB at a BER of 10 -5 as compared to the conventional minimum mean square error detector when communicating over a correlated Rayleigh fading channel. © 2012 IEEE.

A minimum bit error-rate detector for amplify and forward relaying systems

KAUST Repository

Ahmed, Qasim Zeeshan

2012-05-01

In this paper, a new detector is being proposed for amplify-and-forward (AF) relaying system when communicating with the assistance of L number of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the system. The complexity of the system is further reduced by implementing this detector adaptively. The proposed detector is free from channel estimation. Our results demonstrate that the proposed detector is capable of achieving a gain of more than 1-dB at a BER of 10 -5 as compared to the conventional minimum mean square error detector when communicating over a correlated Rayleigh fading channel. © 2012 IEEE.

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

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.

HIGH-POWER TURBODRILL AND DRILL BIT FOR DRILLING WITH COILED TUBING

Energy Technology Data Exchange (ETDEWEB)

Robert Radtke; David Glowka; Man Mohan Rai; David Conroy; Tim Beaton; Rocky Seale; Joseph Hanna; Smith Neyrfor; Homer Robertson

2008-03-31

Commercial introduction of Microhole Technology to the gas and oil drilling industry requires an effective downhole drive mechanism which operates efficiently at relatively high RPM and low bit weight for delivering efficient power to the special high RPM drill bit for ensuring both high penetration rate and long bit life. This project entails developing and testing a more efficient 2-7/8 in. diameter Turbodrill and a novel 4-1/8 in. diameter drill bit for drilling with coiled tubing. The high-power Turbodrill were developed to deliver efficient power, and the more durable drill bit employed high-temperature cutters that can more effectively drill hard and abrasive rock. This project teams Schlumberger Smith Neyrfor and Smith Bits, and NASA AMES Research Center with Technology International, Inc (TII), to deliver a downhole, hydraulically-driven power unit, matched with a custom drill bit designed to drill 4-1/8 in. boreholes with a purpose-built coiled tubing rig. The U.S. Department of Energy National Energy Technology Laboratory has funded Technology International Inc. Houston, Texas to develop a higher power Turbodrill and drill bit for use in drilling with a coiled tubing unit. This project entails developing and testing an effective downhole drive mechanism and a novel drill bit for drilling 'microholes' with coiled tubing. The new higher power Turbodrill is shorter, delivers power more efficiently, operates at relatively high revolutions per minute, and requires low weight on bit. The more durable thermally stable diamond drill bit employs high-temperature TSP (thermally stable) diamond cutters that can more effectively drill hard and abrasive rock. Expectations are that widespread adoption of microhole technology could spawn a wave of 'infill development' drilling of wells spaced between existing wells, which could tap potentially billions of barrels of bypassed oil at shallow depths in mature producing areas. At the same time, microhole

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.

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.

Bit-error-rate testing of fiber optic data links for MMIC-based phased array antennas

Science.gov (United States)

Shalkhauser, K. A.; Kunath, R. R.; Daryoush, A. S.

1990-01-01

The measured bit-error-rate (BER) performance of a fiber optic data link to be used in satellite communications systems is presented and discussed. In the testing, the link was measured for its ability to carry high burst rate, serial-minimum shift keyed (SMSK) digital data similar to those used in actual space communications systems. The fiber optic data link, as part of a dual-segment injection-locked RF fiber optic link system, offers a means to distribute these signals to the many radiating elements of a phased array antenna. Test procedures, experimental arrangements, and test results are presented.

Bit error rate testing of fiber optic data links for MMIC-based phased array antennas

Science.gov (United States)

Shalkhauser, K. A.; Kunath, R. R.; Daryoush, A. S.

1990-01-01

The measured bit-error-rate (BER) performance of a fiber optic data link to be used in satellite communications systems is presented and discussed. In the testing, the link was measured for its ability to carry high burst rate, serial-minimum shift keyed (SMSK) digital data similar to those used in actual space communications systems. The fiber optic data link, as part of a dual-segment injection-locked RF fiber optic link system, offers a means to distribute these signals to the many radiating elements of a phased array antenna. Test procedures, experimental arrangements, and test results are presented.

Inclusive bit error rate analysis for coherent optical code-division multiple-access system

Science.gov (United States)

Katz, Gilad; Sadot, Dan

2002-06-01

Inclusive noise and bit error rate (BER) analysis for optical code-division multiplexing (OCDM) using coherence techniques is presented. The analysis contains crosstalk calculation of the mutual field variance for different number of users. It is shown that the crosstalk noise depends deeply on the receiver integration time, the laser coherence time, and the number of users. In addition, analytical results of the power fluctuation at the received channel due to the data modulation at the rejected channels are presented. The analysis also includes amplified spontaneous emission (ASE)-related noise effects of in-line amplifiers in a long-distance communication link.

Novel ultra-wideband photonic signal generation and transmission featuring digital signal processing bit error rate measurements

DEFF Research Database (Denmark)

Gibbon, Timothy Braidwood; Yu, Xianbin; Tafur Monroy, Idelfonso

2009-01-01

We propose the novel generation of photonic ultra-wideband signals using an uncooled DFB laser. For the first time we experimentally demonstrate bit-for-bit DSP BER measurements for transmission of a 781.25 Mbit/s photonic UWB signal.......We propose the novel generation of photonic ultra-wideband signals using an uncooled DFB laser. For the first time we experimentally demonstrate bit-for-bit DSP BER measurements for transmission of a 781.25 Mbit/s photonic UWB signal....

Low-Bit Rate Feedback Strategies for Iterative IA-Precoded MIMO-OFDM-Based Systems

Science.gov (United States)

Teodoro, Sara; Silva, Adão; Dinis, Rui; Gameiro, Atílio

2014-01-01

Interference alignment (IA) is a promising technique that allows high-capacity gains in interference channels, but which requires the knowledge of the channel state information (CSI) for all the system links. We design low-complexity and low-bit rate feedback strategies where a quantized version of some CSI parameters is fed back from the user terminal (UT) to the base station (BS), which shares it with the other BSs through a limited-capacity backhaul network. This information is then used by BSs to perform the overall IA design. With the proposed strategies, we only need to send part of the CSI information, and this can even be sent only once for a set of data blocks transmitted over time-varying channels. These strategies are applied to iterative MMSE-based IA techniques for the downlink of broadband wireless OFDM systems with limited feedback. A new robust iterative IA technique, where channel quantization errors are taken into account in IA design, is also proposed and evaluated. With our proposed strategies, we need a small number of quantization bits to transmit and share the CSI, when comparing with the techniques used in previous works, while allowing performance close to the one obtained with perfect channel knowledge. PMID:24678274

Bit-error-rate performance analysis of self-heterodyne detected radio-over-fiber links using phase and intensity modulation

DEFF Research Database (Denmark)

Yin, Xiaoli; Yu, Xianbin; Tafur Monroy, Idelfonso

2010-01-01

We theoretically and experimentally investigate the performance of two self-heterodyne detected radio-over-fiber (RoF) links employing phase modulation (PM) and quadrature biased intensity modulation (IM), in term of bit-error-rate (BER) and optical signal-to-noise-ratio (OSNR). In both links, self...

FODA/IBEA satellite access scheme for MIXED traffic at variable bit and coding rates system description

OpenAIRE

Celandroni, Nedo; Ferro, Erina; Mihal, Vlado; Potort?, Francesco

1992-01-01

This report describes the FODA system working at variable coding and bit rates (FODA/IBEA-TDMA) FODA/IBEA is the natural evolution of the FODA-TDMA satellite access scheme working at 2 Mbit/s fixed rate with data 1/2 coded or uncoded. FODA-TDMA was used in the European SATINE-II experiment [8]. We remind here that the term FODA/IBEA system is comprehensive of the FODA/IBEA-TDMA (1) satellite access scheme and of the hardware prototype realised by the Marconi R.C. (U.K.). Both of them come fro...

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.

All-optical wavelength conversion at bit rates above 10 Gb/s using semiconductor optical amplifiers

DEFF Research Database (Denmark)

Jørgensen, Carsten; Danielsen, Søren Lykke; Stubkjær, Kristian

1997-01-01

This work assesses the prospects for high-speed all-optical wavelength conversion using the simple optical interaction with the gain in semiconductor optical amplifiers (SOAs) via the interband carrier recombination. Operation and design guidelines for conversion speeds above 10 Gb/s are described...... and the various tradeoffs are discussed. Experiments at bit rates up to 40 Gb/s are presented for both cross-gain modulation (XGM) and cross-phase modulation (XPM) in SOAs demonstrating the high-speed capability of these techniques...

Student laboratory experiments exploring optical fibre communication systems, eye diagrams, and bit error rates

Science.gov (United States)

Walsh, Douglas; Moodie, David; Mauchline, Iain; Conner, Steve; Johnstone, Walter; Culshaw, Brian

2005-06-01

Optical fibre communications has proved to be one of the key application areas, which created, and ultimately propelled the global growth of the photonics industry over the last twenty years. Consequently the teaching of the principles of optical fibre communications has become integral to many university courses covering photonics technology. However to reinforce the fundamental principles and key technical issues students examine in their lecture courses and to develop their experimental skills, it is critical that the students also obtain hands-on practical experience of photonics components, instruments and systems in an associated teaching laboratory. In recognition of this need OptoSci, in collaboration with university academics, commercially developed a fibre optic communications based educational package (ED-COM). This educator kit enables students to; investigate the characteristics of the individual communications system components (sources, transmitters, fibre, receiver), examine and interpret the overall system performance limitations imposed by attenuation and dispersion, conduct system design and performance analysis. To further enhance the experimental programme examined in the fibre optic communications kit, an extension module to ED-COM has recently been introduced examining one of the most significant performance parameters of digital communications systems, the bit error rate (BER). This add-on module, BER(COM), enables students to generate, evaluate and investigate signal quality trends by examining eye patterns, and explore the bit-rate limitations imposed on communication systems by noise, attenuation and dispersion. This paper will examine the educational objectives, background theory, and typical results for these educator kits, with particular emphasis on BER(COM).

Minimal-post-processing 320-Gbps true random bit generation using physical white chaos.

Science.gov (United States)

Wang, Anbang; Wang, Longsheng; Li, Pu; Wang, Yuncai

2017-02-20

Chaotic external-cavity semiconductor laser (ECL) is a promising entropy source for generation of high-speed physical random bits or digital keys. The rate and randomness is unfortunately limited by laser relaxation oscillation and external-cavity resonance, and is usually improved by complicated post processing. Here, we propose using a physical broadband white chaos generated by optical heterodyning of two ECLs as entropy source to construct high-speed random bit generation (RBG) with minimal post processing. The optical heterodyne chaos not only has a white spectrum without signature of relaxation oscillation and external-cavity resonance but also has a symmetric amplitude distribution. Thus, after quantization with a multi-bit analog-digital-convertor (ADC), random bits can be obtained by extracting several least significant bits (LSBs) without any other processing. In experiments, a white chaos with a 3-dB bandwidth of 16.7 GHz is generated. Its entropy rate is estimated as 16 Gbps by single-bit quantization which means a spectrum efficiency of 96%. With quantization using an 8-bit ADC, 320-Gbps physical RBG is achieved by directly extracting 4 LSBs at 80-GHz sampling rate.

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.

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.

Analyzing the propagation behavior of scintillation index and bit error rate of a partially coherent flat-topped laser beam in oceanic turbulence.

Science.gov (United States)

Yousefi, Masoud; Golmohammady, Shole; Mashal, Ahmad; Kashani, Fatemeh Dabbagh

2015-11-01

In this paper, on the basis of the extended Huygens-Fresnel principle, a semianalytical expression for describing on-axis scintillation index of a partially coherent flat-topped (PCFT) laser beam of weak to moderate oceanic turbulence is derived; consequently, by using the log-normal intensity probability density function, the bit error rate (BER) is evaluated. The effects of source factors (such as wavelength, order of flatness, and beam width) and turbulent ocean parameters (such as Kolmogorov microscale, relative strengths of temperature and salinity fluctuations, rate of dissipation of the mean squared temperature, and rate of dissipation of the turbulent kinetic energy per unit mass of fluid) on propagation behavior of scintillation index, and, hence, on BER, are studied in detail. Results indicate that, in comparison with a Gaussian beam, a PCFT laser beam with a higher order of flatness is found to have lower scintillations. In addition, the scintillation index and BER are most affected when salinity fluctuations in the ocean dominate temperature fluctuations.

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.

The Design of a Single-Bit CMOS Image Sensor for Iris Recognition Applications

Directory of Open Access Journals (Sweden)

Keunyeol Park

2018-02-01

Full Text Available This paper presents a single-bit CMOS image sensor (CIS that uses a data processing technique with an edge detection block for simple iris segmentation. In order to recognize the iris image, the image sensor conventionally captures high-resolution image data in digital code, extracts the iris data, and then compares it with a reference image through a recognition algorithm. However, in this case, the frame rate decreases by the time required for digital signal conversion of multi-bit digital data through the analog-to-digital converter (ADC in the CIS. In order to reduce the overall processing time as well as the power consumption, we propose a data processing technique with an exclusive OR (XOR logic gate to obtain single-bit and edge detection image data instead of multi-bit image data through the ADC. In addition, we propose a logarithmic counter to efficiently measure single-bit image data that can be applied to the iris recognition algorithm. The effective area of the proposed single-bit image sensor (174 × 144 pixel is 2.84 mm2 with a 0.18 μm 1-poly 4-metal CMOS image sensor process. The power consumption of the proposed single-bit CIS is 2.8 mW with a 3.3 V of supply voltage and 520 frame/s of the maximum frame rates. The error rate of the ADC is 0.24 least significant bit (LSB on an 8-bit ADC basis at a 50 MHz sampling frequency.

The Design of a Single-Bit CMOS Image Sensor for Iris Recognition Applications.

Science.gov (United States)

Park, Keunyeol; Song, Minkyu; Kim, Soo Youn

2018-02-24

This paper presents a single-bit CMOS image sensor (CIS) that uses a data processing technique with an edge detection block for simple iris segmentation. In order to recognize the iris image, the image sensor conventionally captures high-resolution image data in digital code, extracts the iris data, and then compares it with a reference image through a recognition algorithm. However, in this case, the frame rate decreases by the time required for digital signal conversion of multi-bit digital data through the analog-to-digital converter (ADC) in the CIS. In order to reduce the overall processing time as well as the power consumption, we propose a data processing technique with an exclusive OR (XOR) logic gate to obtain single-bit and edge detection image data instead of multi-bit image data through the ADC. In addition, we propose a logarithmic counter to efficiently measure single-bit image data that can be applied to the iris recognition algorithm. The effective area of the proposed single-bit image sensor (174 × 144 pixel) is 2.84 mm² with a 0.18 μm 1-poly 4-metal CMOS image sensor process. The power consumption of the proposed single-bit CIS is 2.8 mW with a 3.3 V of supply voltage and 520 frame/s of the maximum frame rates. The error rate of the ADC is 0.24 least significant bit (LSB) on an 8-bit ADC basis at a 50 MHz sampling frequency.

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...

Bit Error Rate Analysis for MC-CDMA Systems in Nakagami- Fading Channels

Directory of Open Access Journals (Sweden)

Li Zexian

2004-01-01

Full Text Available Multicarrier code division multiple access (MC-CDMA is a promising technique that combines orthogonal frequency division multiplexing (OFDM with CDMA. In this paper, based on an alternative expression for the -function, characteristic function and Gaussian approximation, we present a new practical technique for determining the bit error rate (BER of multiuser MC-CDMA systems in frequency-selective Nakagami- fading channels. The results are applicable to systems employing coherent demodulation with maximal ratio combining (MRC or equal gain combining (EGC. The analysis assumes that different subcarriers experience independent fading channels, which are not necessarily identically distributed. The final average BER is expressed in the form of a single finite range integral and an integrand composed of tabulated functions which can be easily computed numerically. The accuracy of the proposed approach is demonstrated with computer simulations.

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

.4% greater than 12-bit. Absolute film dosimetry in a region downstream of a stainless steel rod revealed that 16-bit calculated dose, with and without MAR, agreed more closely with film results (1%-2% less than film) as compared to 12-bit reconstructions (5.6%-6.5% less than film measurements). Gamma analysis revealed that 16-bit dose calculations were better matched to film results than 12-bit ({approx}10% higher pass rates for 16-bit). Similar results were observed in two patient cases; the largest discrepancy was observed for a femur case where 12-bit doses, both with and without MAR correction, were 6-7 Gy lower ({approx}17%-20% of the prescription dose) as compared to 16-bit dose calculations. However, when beams are not directly traversing metal, such as a prostate cancer case with bilateral hip prostheses; the impact of 16-bit reconstruction was diminished. Conclusions: These results suggest that it may be desirable to implement 16-bit MAR-corrected images for treatment planning purposes, which can provide a more accurate dosimetric approach coupled with improved visualization by suppression of CT artifacts.

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.

Performance evaluations of hybrid modulation with different optical labels over PDQ in high bit-rate OLS network systems.

Science.gov (United States)

Xu, M; Li, Y; Kang, T Z; Zhang, T S; Ji, J H; Yang, S W

2016-11-14

Two orthogonal modulation optical label switching(OLS) schemes, which are based on payload of polarization multiplexing-differential quadrature phase shift keying(POLMUX-DQPSK or PDQ) modulated with identifications of duobinary (DB) label and pulse position modulation(PPM) label, are researched in high bit-rate OLS network. The BER performance of hybrid modulation with payload and label signals are discussed and evaluated in theory and simulation. The theoretical BER expressions of PDQ, PDQ-DB and PDQ-PPM are given with analysis method of hybrid modulation encoding in different the bit-rate ratios of payload and label. Theoretical derivation results are shown that the payload of hybrid modulation has a certain gain of receiver sensitivity than payload without label. The sizes of payload BER gain obtained from hybrid modulation are related to the different types of label. The simulation results are consistent with that of theoretical conclusions. The extinction ratio (ER) conflicting between hybrid encoding of intensity and phase types can be compromised and optimized in OLS system of hybrid modulation. The BER analysis method of hybrid modulation encoding in OLS system can be applied to other n-ary hybrid modulation or combination modulation systems.

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.

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

High bit rate germanium single photon detectors for 1310nm

Science.gov (United States)

Seamons, J. A.; Carroll, M. S.

2008-04-01

There is increasing interest in development of high speed, low noise and readily fieldable near infrared (NIR) single photon detectors. InGaAs/InP Avalanche photodiodes (APD) operated in Geiger mode (GM) are a leading choice for NIR due to their preeminence in optical networking. After-pulsing is, however, a primary challenge to operating InGaAs/InP single photon detectors at high frequencies1. After-pulsing is the effect of charge being released from traps that trigger false ("dark") counts. To overcome this problem, hold-off times between detection windows are used to allow the traps to discharge to suppress after-pulsing. The hold-off time represents, however, an upper limit on detection frequency that shows degradation beginning at frequencies of ~100 kHz in InGaAs/InP. Alternatively, germanium (Ge) single photon avalanche photodiodes (SPAD) have been reported to have more than an order of magnitude smaller charge trap densities than InGaAs/InP SPADs2, which allowed them to be successfully operated with passive quenching2 (i.e., no gated hold off times necessary), which is not possible with InGaAs/InP SPADs, indicating a much weaker dark count dependence on hold-off time consistent with fewer charge traps. Despite these encouraging results suggesting a possible higher operating frequency limit for Ge SPADs, little has been reported on Ge SPAD performance at high frequencies presumably because previous work with Ge SPADs has been discouraged by a strong demand to work at 1550 nm. NIR SPADs require cooling, which in the case of Ge SPADs dramatically reduces the quantum efficiency of the Ge at 1550 nm. Recently, however, advantages to working at 1310 nm have been suggested which combined with a need to increase quantum bit rates for quantum key distribution (QKD) motivates examination of Ge detectors performance at very high detection rates where InGaAs/InP does not perform as well. Presented in this paper are measurements of a commercially available Ge APD

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)

Power consumption analysis of constant bit rate data transmission over 3G mobile wireless networks

DEFF Research Database (Denmark)

Wang, Le; Ukhanova, Ann; Belyaev, Evgeny

2011-01-01

This paper presents the analysis of the power consumption of data transmission with constant bit rate over 3G mobile wireless networks. Our work includes the description of the transition state machine in 3G networks, followed by the detailed energy consumption analysis and measurement results...... of the radio link power consumption. Based on these description and analysis, we propose power consumption model. The power model was evaluated on the smartphone Nokia N900, which follows a 3GPP Release 5 and 6 supporting HSDPA/HSPA data bearers. Further we propose method of parameters selection for 3GPP...... transition state machine that allows to decrease power consumption on the mobile device....

Power penalties for multi-level PAM modulation formats at arbitrary bit error rates

Science.gov (United States)

Kaliteevskiy, Nikolay A.; Wood, William A.; Downie, John D.; Hurley, Jason; Sterlingov, Petr

2016-03-01

There is considerable interest in combining multi-level pulsed amplitude modulation formats (PAM-L) and forward error correction (FEC) in next-generation, short-range optical communications links for increased capacity. In this paper we derive new formulas for the optical power penalties due to modulation format complexity relative to PAM-2 and due to inter-symbol interference (ISI). We show that these penalties depend on the required system bit-error rate (BER) and that the conventional formulas overestimate link penalties. Our corrections to the standard formulas are very small at conventional BER levels (typically 1×10-12) but become significant at the higher BER levels enabled by FEC technology, especially for signal distortions due to ISI. The standard formula for format complexity, P = 10log(L-1), is shown to overestimate the actual penalty for PAM-4 and PAM-8 by approximately 0.1 and 0.25 dB respectively at 1×10-3 BER. Then we extend the well-known PAM-2 ISI penalty estimation formula from the IEEE 802.3 standard 10G link modeling spreadsheet to the large BER case and generalize it for arbitrary PAM-L formats. To demonstrate and verify the BER dependence of the ISI penalty, a set of PAM-2 experiments and Monte-Carlo modeling simulations are reported. The experimental results and simulations confirm that the conventional formulas can significantly overestimate ISI penalties at relatively high BER levels. In the experiments, overestimates up to 2 dB are observed at 1×10-3 BER.

Cheat sensitive quantum bit commitment via pre- and post-selected quantum states

Science.gov (United States)

Li, Yan-Bing; Wen, Qiao-Yan; Li, Zi-Chen; Qin, Su-Juan; Yang, Ya-Tao

2014-01-01

Cheat sensitive quantum bit commitment is a most important and realizable quantum bit commitment (QBC) protocol. By taking advantage of quantum mechanism, it can achieve higher security than classical bit commitment. In this paper, we propose a QBC schemes based on pre- and post-selected quantum states. The analysis indicates that both of the two participants' cheat strategies will be detected with non-zero probability. And the protocol can be implemented with today's technology as a long-term quantum memory is not needed.

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

Bit Error-Rate Minimizing Detector for Amplify-and-Forward Relaying Systems Using Generalized Gaussian Kernel

KAUST Repository

Ahmed, Qasim Zeeshan

2013-01-01

In this letter, a new detector is proposed for amplifyand- forward (AF) relaying system when communicating with the assistance of relays. The major goal of this detector is to improve the bit error rate (BER) performance of the receiver. The probability density function is estimated with the help of kernel density technique. A generalized Gaussian kernel is proposed. This new kernel provides more flexibility and encompasses Gaussian and uniform kernels as special cases. The optimal window width of the kernel is calculated. Simulations results show that a gain of more than 1 dB can be achieved in terms of BER performance as compared to the minimum mean square error (MMSE) receiver when communicating over Rayleigh fading channels.

Power consumption analysis of constant bit rate video transmission over 3G networks

DEFF Research Database (Denmark)

Ukhanova, Ann; Belyaev, Evgeny; Wang, Le

2012-01-01

This paper presents an analysis of the power consumption of video data transmission with constant bit rate over 3G mobile wireless networks. The work includes the description of the radio resource control transition state machine in 3G networks, followed by a detailed power consumption analysis...... and measurements of the radio link power consumption. Based on this description and analysis, we propose our power consumption model. The power model was evaluated on a smartphone Nokia N900, which follows 3GPP Release 5 and 6 supporting HSDPA/HSUPA data bearers. We also propose a method for parameter selection...... for the 3GPP transition state machine that allows to decrease power consumption on a mobile device taking signaling traffic, buffer size and latency restrictions into account. Furthermore, we discuss the gain in power consumption vs. PSNR for transmitted video and show the possibility of performing power...

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...

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...

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

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.

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

Practical scheme to share a secret key through a quantum channel with a 27.6% bit error rate

International Nuclear Information System (INIS)

Chau, H.F.

2002-01-01

A secret key shared through quantum key distribution between two cooperative players is secure against any eavesdropping attack allowed by the laws of physics. Yet, such a key can be established only when the quantum channel error rate due to eavesdropping or imperfect apparatus is low. Here, a practical quantum key distribution scheme by making use of an adaptive privacy amplification procedure with two-way classical communication is reported. Then, it is proven that the scheme generates a secret key whenever the bit error rate of the quantum channel is less than 0.5-0.1√(5)≅27.6%, thereby making it the most error resistant scheme known to date

Will available bit rate (ABR) services give us the capability to offer virtual LANs over wide-area ATM networks?

Science.gov (United States)

Ferrandiz, Ana; Scallan, Gavin

1995-10-01

The available bit rate (ABR) service allows connections to exceed their negotiated data rates during the life of the connections when excess capacity is available in the network. These connections are subject to flow control from the network in the event of network congestion. The ability to dynamically adjust the data rate of the connection can provide improved utilization of the network and be a valuable service to end users. ABR type service is therefore appropriate for the transmission of bursty LAN traffic over a wide area network in a manner that is more efficient and cost effective than allocating bandwdith at the peak cell rate. This paper describes the ABR service and discusses if it is realistic to operate a LAN like service over a wide area using ABR.

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.

Enhancing Performance and Bit Rates in a Brain-Computer Interface System With Phase-to-Amplitude Cross-Frequency Coupling: Evidences From Traditional c-VEP, Fast c-VEP, and SSVEP Designs.

Science.gov (United States)

Dimitriadis, Stavros I; Marimpis, Avraam D

2018-01-01

A brain-computer interface (BCI) is a channel of communication that transforms brain activity into specific commands for manipulating a personal computer or other home or electrical devices. In other words, a BCI is an alternative way of interacting with the environment by using brain activity instead of muscles and nerves. For that reason, BCI systems are of high clinical value for targeted populations suffering from neurological disorders. In this paper, we present a new processing approach in three publicly available BCI data sets: (a) a well-known multi-class ( N = 6) coded-modulated Visual Evoked potential (c-VEP)-based BCI system for able-bodied and disabled subjects; (b) a multi-class ( N = 32) c-VEP with slow and fast stimulus representation; and (c) a steady-state Visual Evoked potential (SSVEP) multi-class ( N = 5) flickering BCI system. Estimating cross-frequency coupling (CFC) and namely δ-θ [δ: (0.5-4 Hz), θ: (4-8 Hz)] phase-to-amplitude coupling (PAC) within sensor and across experimental time, we succeeded in achieving high classification accuracy and Information Transfer Rates (ITR) in the three data sets. Our approach outperformed the originally presented ITR on the three data sets. The bit rates obtained for both the disabled and able-bodied subjects reached the fastest reported level of 324 bits/min with the PAC estimator. Additionally, our approach outperformed alternative signal features such as the relative power (29.73 bits/min) and raw time series analysis (24.93 bits/min) and also the original reported bit rates of 10-25 bits/min . In the second data set, we succeeded in achieving an average ITR of 124.40 ± 11.68 for the slow 60 Hz and an average ITR of 233.99 ± 15.75 for the fast 120 Hz. In the third data set, we succeeded in achieving an average ITR of 106.44 ± 8.94. Current methodology outperforms any previous methodologies applied to each of the three free available BCI datasets.

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

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

Bit rate and pulse width dependence of four-wave mixing of short optical pulses in semiconductor optical amplifiers

DEFF Research Database (Denmark)

Diez, S.; Mecozzi, A.; Mørk, Jesper

1999-01-01

We investigate the saturation properties of four-wave mixing of short optical pulses in a semiconductor optical amplifier. By varying the gain of the optical amplifier, we find a strong dependence of both conversion efficiency and signal-to-background ratio on pulse width and bit rate....... In particular, the signal-to-background ratio can be optimized for a specific amplifier gain. This behavior, which is coherently described in experiment and theory, is attributed to the dynamics of the amplified spontaneous emission, which is the main source of noise in a semiconductor optical amplifier....

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...

Time Domain Equalizer Design Using Bit Error Rate Minimization for UWB Systems

Directory of Open Access Journals (Sweden)

Syed Imtiaz Husain

2009-01-01

Full Text Available Ultra-wideband (UWB communication systems occupy huge bandwidths with very low power spectral densities. This feature makes the UWB channels highly rich in resolvable multipaths. To exploit the temporal diversity, the receiver is commonly implemented through a Rake. The aim to capture enough signal energy to maintain an acceptable output signal-to-noise ratio (SNR dictates a very complicated Rake structure with a large number of fingers. Channel shortening or time domain equalizer (TEQ can simplify the Rake receiver design by reducing the number of significant taps in the effective channel. In this paper, we first derive the bit error rate (BER of a multiuser and multipath UWB system in the presence of a TEQ at the receiver front end. This BER is then written in a form suitable for traditional optimization. We then present a TEQ design which minimizes the BER of the system to perform efficient channel shortening. The performance of the proposed algorithm is compared with some generic TEQ designs and other Rake structures in UWB channels. It is shown that the proposed algorithm maintains a lower BER along with efficiently shortening the channel.

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

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 ...

Stereoscopic Visual Attention-Based Regional Bit Allocation Optimization for Multiview Video Coding

Directory of Open Access Journals (Sweden)

Dai Qionghai

2010-01-01

Full Text Available We propose a Stereoscopic Visual Attention- (SVA- based regional bit allocation optimization for Multiview Video Coding (MVC by the exploiting visual redundancies from human perceptions. We propose a novel SVA model, where multiple perceptual stimuli including depth, motion, intensity, color, and orientation contrast are utilized, to simulate the visual attention mechanisms of human visual system with stereoscopic perception. Then, a semantic region-of-interest (ROI is extracted based on the saliency maps of SVA. Both objective and subjective evaluations of extracted ROIs indicated that the proposed SVA model based on ROI extraction scheme outperforms the schemes only using spatial or/and temporal visual attention clues. Finally, by using the extracted SVA-based ROIs, a regional bit allocation optimization scheme is presented to allocate more bits on SVA-based ROIs for high image quality and fewer bits on background regions for efficient compression purpose. Experimental results on MVC show that the proposed regional bit allocation algorithm can achieve over % bit-rate saving while maintaining the subjective image quality. Meanwhile, the image quality of ROIs is improved by  dB at the cost of insensitive image quality degradation of the background image.

Diamonds are forever: drill bit advances may offer cheaper and stronger alternatives

Energy Technology Data Exchange (ETDEWEB)

Mahoney, J.

2001-02-01

The rise to prominence of polycrystalline diamond compact (PDC) and diamond-impregnated drill bits, slowly providing stiff competition to the roller-cone type bits that for many years was the standard in the drilling industry, is discussed. A roller-cone drill bit, although much improved by heat treatment of the metal and the addition of tungsten carbide, is still mostly steel. It works by crushing the rock by overcoming its compressive strength, whereas PDC drill bits shear the rock away in a manner similar to scraping ice from a car windshield. PDC bits typically have three to six cutting surfaces, each one edged with a row of polycrystalline diamond cutters, bonded to a tungsten carbide base by a process called microwave sintering. Compared to roller cones, PDCs drill at least twice as fast, especially in the soft rock and clay where they have been used principally. In addition to saving rig time, PDC bits can handle longer runs; in the right application it is possible to drill the total depth of a well with only one bit. The microwave-sintered tungsten carbide also has higher corrosion resistance than the same material bonded under high pressure; PDCs are also less subject to mechanical failure than roller cones which use moveable bearings, seals and rotating cones. 1 photo.

A novel frame-level constant-distortion bit allocation for smooth H.264/AVC video quality

Science.gov (United States)

Liu, Li; Zhuang, Xinhua

2009-01-01

It is known that quality fluctuation has a major negative effect on visual perception. In previous work, we introduced a constant-distortion bit allocation method [1] for H.263+ encoder. However, the method in [1] can not be adapted to the newest H.264/AVC encoder directly as the well-known chicken-egg dilemma resulted from the rate-distortion optimization (RDO) decision process. To solve this problem, we propose a new two stage constant-distortion bit allocation (CDBA) algorithm with enhanced rate control for H.264/AVC encoder. In stage-1, the algorithm performs RD optimization process with a constant quantization QP. Based on prediction residual signals from stage-1 and target distortion for smooth video quality purpose, the frame-level bit target is allocated by using a close-form approximations of ratedistortion relationship similar to [1], and a fast stage-2 encoding process is performed with enhanced basic unit rate control. Experimental results show that, compared with original rate control algorithm provided by H.264/AVC reference software JM12.1, the proposed constant-distortion frame-level bit allocation scheme reduces quality fluctuation and delivers much smoother PSNR on all testing sequences.

Scalable In-Band Optical Notch-Filter Labeling for Ultrahigh Bit Rate Optical Packet Switching

DEFF Research Database (Denmark)

Medhin, Ashenafi Kiros; Galili, Michael; Oxenløwe, Leif Katsuo

2014-01-01

We propose a scalable in-band optical notch-filter labeling scheme for optical packet switching of high-bit-rate data packets. A detailed characterization of the notch-filter labeling scheme and its effect on the quality of the data packet is carried out in simulation and verified by experimental...... demonstrations. The scheme is able to generate more than 91 different labels that can be applied to 640-Gb/s optical time division multiplexed packets causing an eye opening penalty of $1.2-dB. Experimental demonstration shows that up to 256 packets can be uniquely labeled by employing up to eight notch filters...... with only 0.9-dB power penalty to achieve BER of 1E-9. Using the proposed labeling scheme, optical packet switching of 640 Gb/s data packets is experimentally demonstrated in which two data packets are labeled by making none and one spectral hole using a notch filter and are switched using a LiNbO$_3...

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.

10-bit segmented current steering DAC in 90nm CMOS technology

International Nuclear Information System (INIS)

Bringas, R Jr; Dy, F; Gerasta, O J

2015-01-01

This special project presents a 10-Bit 1Gs/s 1.2V/3.3V Digital-to-Analog Converter using1 Poly 9 Metal SAED 90-nm CMOS Technology intended for mixed-signal and power IC applications. To achieve maximum performance with minimum area, the DAC has been implemented in 6+4 Segmentation. The simulation results show a static performance of ±0.56 LSB INL and ±0.79 LSB DNL with a total layout chip area of 0.683 mm 2 .The segmented architecture is implemented using two sub DAC's, which are the LSB and MSB section with certain number bits. The DAC is designed using 4-BitBinary Weighted DAC for the LSB section and 6-BitThermometer-coded DAC for the MSB section. The thermometer-coded architecture provides the most optimized results in terms of linearity through reducing the clock feed-through effect especially in hot switching between multiple transistors. The binary- weighted architecture gives better linearity output in higher frequencies with better saturation in current sources. (paper)

PERBANDINGAN BIT ERROR RATE KODE REED-SOLOMON DENGAN KODE BOSE-CHAUDHURI-HOCQUENGHEM MENGGUNAKAN MODULASI 32-FSK

Directory of Open Access Journals (Sweden)

Eva Yovita Dwi Utami

2016-11-01

Full Text Available Kode Reed-Solomon (RS dan kode Bose-Chaudhuri-Hocquenghem (BCH merupakan kode pengoreksi error yang termasuk dalam jenis kode blok siklis. Kode pengoreksi error diperlukan pada sistem komunikasi untuk memperkecil error pada informasi yang dikirimkan. Dalam makalah ini, disajikan hasil penelitian kinerja BER sistem komunikasi yang menggunakan kode RS, kode BCH, dan sistem yang tidak menggunakan kode RS dan kode BCH, menggunakan modulasi 32-FSK pada kanal Additive White Gaussian Noise (AWGN, Rayleigh dan Rician. Kemampuan memperkecil error diukur menggunakan nilai Bit Error Rate (BER yang dihasilkan. Hasil penelitian menunjukkan bahwa kode RS seiring dengan penambahan nilai SNR, menurunkan nilai BER yang lebih curam bila dibandingkan sistem dengan kode BCH. Sedangkan kode BCH memberikan keunggulan saat SNR bernilai kecil, memiliki BER lebih baik daripada sistem dengan kode RS.

Video steganography based on bit-plane decomposition of wavelet-transformed video

Science.gov (United States)

Noda, Hideki; Furuta, Tomofumi; Niimi, Michiharu; Kawaguchi, Eiji

2004-06-01

This paper presents a steganography method using lossy compressed video which provides a natural way to send a large amount of secret data. The proposed method is based on wavelet compression for video data and bit-plane complexity segmentation (BPCS) steganography. BPCS steganography makes use of bit-plane decomposition and the characteristics of the human vision system, where noise-like regions in bit-planes of a dummy image are replaced with secret data without deteriorating image quality. In wavelet-based video compression methods such as 3-D set partitioning in hierarchical trees (SPIHT) algorithm and Motion-JPEG2000, wavelet coefficients in discrete wavelet transformed video are quantized into a bit-plane structure and therefore BPCS steganography can be applied in the wavelet domain. 3-D SPIHT-BPCS steganography and Motion-JPEG2000-BPCS steganography are presented and tested, which are the integration of 3-D SPIHT video coding and BPCS steganography, and that of Motion-JPEG2000 and BPCS, respectively. Experimental results show that 3-D SPIHT-BPCS is superior to Motion-JPEG2000-BPCS with regard to embedding performance. In 3-D SPIHT-BPCS steganography, embedding rates of around 28% of the compressed video size are achieved for twelve bit representation of wavelet coefficients with no noticeable degradation in video quality.

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.

Worst-case residual clipping noise power model for bit loading in LACO-OFDM

KAUST Repository

Zhang, Zhenyu; Chaaban, Anas; Shen, Chao; Elgala, Hany; Ng, Tien Khee; Ooi, Boon S.; Alouini, Mohamed-Slim

2018-01-01

Layered ACO-OFDM enjoys better spectral efficiency than ACO-OFDM, but its performance is challenged by residual clipping noise (RCN). In this paper, the power of RCN of LACO-OFDM is analyzed and modeled. As RCN is data-dependent, the worst-case situation is considered. A worst-case indicator is defined for relating the power of RCN and the power of noise at the receiver, wherein a linear relation is shown to be a practical approximation. An LACO-OFDM bit-loading experiment is performed to examine the proposed RCN power model for data rates of 6 to 7 Gbps. The experiment's results show that accounting for RCN has two advantages. First, it leads to better bit loading and achieves up to 59% lower overall bit-error rate (BER) than when the RCN is ignored. Second, it balances the BER across layers, which is a desired property from a channel coding perspective.

BetaBit: A fast generator of autocorrelated binary processes for geophysical research

Science.gov (United States)

Serinaldi, Francesco; Lombardo, Federico

2017-05-01

We introduce a fast and efficient non-iterative algorithm, called BetaBit, to simulate autocorrelated binary processes describing the occurrence of natural hazards, system failures, and other physical and geophysical phenomena characterized by persistence, temporal clustering, and low rate of occurrence. BetaBit overcomes the simulation constraints posed by the discrete nature of the marginal distributions of binary processes by using the link existing between the correlation coefficients of this process and those of the standard Gaussian processes. The performance of BetaBit is tested on binary signals with power-law and exponentially decaying autocorrelation functions (ACFs) corresponding to Hurst-Kolmogorov and Markov processes, respectively. An application to real-world sequences describing rainfall intermittency and the occurrence of strong positive phases of the North Atlantic Oscillation (NAO) index shows that BetaBit can also simulate surrogate data preserving the empirical ACF as well as signals with autoregressive moving average (ARMA) dependence structures. Extensions to cyclo-stationary processes accounting for seasonal fluctuations are also discussed.

FY 1975 Report on results of Sunshine Project. Development of techniques of digging high-temperature beds (Researches on roller cutter bits); 1975 nendo koon chiso kussaku gijutsu no kaihatsu. Roller cutter bit no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1976-03-31

It is necessary to establish the techniques for digging bedrocks under elevated temperature and pressure for development and utilization of geothermal energy. This project is aimed at development of heat- and wear-resistant bit cutters, which have efficient tooth edge forms and arrangements. Another factor that determines bit serviceability is the bearing built in a cutter, and this project is also aimed at development of long-serviceable bit bearings by improving their resistance to heat. Four types of bits were developed, on a trial basis, and tested (size: 8.625 inches, two types of tooth forms, different shapes and arrangements of insert tips). They were tested for, e.g., their excavation rate, under the conditions of 5 tons as load and 100 rpm. It is found that their excavation rate vary with load, speed of rotation, tooth height and tooth form. Excavation torque increases in almost proportion to load. The sliding bearings of silver and its alloy were tested, to confirm the effects of silver. It is necessary to conduct the field tests in an actual geothermal area of high rock temperature and the ground tests with test machines to dig heated rocks in and after FY 1975, for overall evaluation of the bits developed. (NEDO)

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.

Worst-case residual clipping noise power model for bit loading in LACO-OFDM

KAUST Repository

Zhang, Zhenyu

2018-03-19

Layered ACO-OFDM enjoys better spectral efficiency than ACO-OFDM, but its performance is challenged by residual clipping noise (RCN). In this paper, the power of RCN of LACO-OFDM is analyzed and modeled. As RCN is data-dependent, the worst-case situation is considered. A worst-case indicator is defined for relating the power of RCN and the power of noise at the receiver, wherein a linear relation is shown to be a practical approximation. An LACO-OFDM bit-loading experiment is performed to examine the proposed RCN power model for data rates of 6 to 7 Gbps. The experiment\\'s results show that accounting for RCN has two advantages. First, it leads to better bit loading and achieves up to 59% lower overall bit-error rate (BER) than when the RCN is ignored. Second, it balances the BER across layers, which is a desired property from a channel coding perspective.

Controlling torque and cutting costs: steerable drill bits deliver in Latin America

Energy Technology Data Exchange (ETDEWEB)

Barton, Steve; Garcia, Alexis; Amorim, Dalmo [ReedHycalog, Stonehouse (United Kingdom); Iramina, Wilson [University of Sao Paulo (USP), SP (Brazil); Herrera, Gabriel

2008-07-01

Tool face Control is widely regarded as one of the greatest directional drilling challenges with a Fixed Cutter (FC) drill bit on a Steerable Motor assembly. Tool face offset is proportional to the torque generated by the bit, and by nature, FC bits are capable of generating high levels of torque. If large changes in downhole torque are produced while drilling, this will cause rotation of the drill string, and loss of tool face orientation. This results in inefficient drilling and increases risk of bit and downhole tool damage. This paper examines the effect of various FC drill bit components to determine the key design requirements to deliver a smooth torque response and an improved directional performance. Included is a review of the results from comprehensive laboratory testing to determine the effectiveness of a number of different configurations of removable Torque Controlling Components (TCC). These, in combination with specific cutting structure layouts, combine to provide predictable torque response while optimized for high rates of penetration. In addition, unique gauge geometry is disclosed that was engineered to reduce drag and deliver improved borehole quality. This gauge design produces less torque when sliding and beneficial gauge pad interaction with the borehole when in rotating mode. Field performance studies from within Latin America clearly demonstrate that matching TCC, an optimized cutting structure, and gauge geometry to a steerable assembly delivers smooth torque response and improved directional control. Benefits with regard to improved stability are also discussed. Successful application has resulted in significant time and cost savings for the operator, demonstrating that Stability and Steerability improvements can be achieved with an increase in penetration rate. (author)

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

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.)

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

Corrected multiple upsets and bit reversals for improved 1-s resolution measurements

International Nuclear Information System (INIS)

Brucker, G.J.; Stassinopoulos, E.G.; Stauffer, C.A.

1994-01-01

Previous work has studied the generation of single and multiple errors in control and irradiated static RAM samples (Harris 6504RH) which were exposed to heavy ions for relatively long intervals of time (minute), and read out only after the beam was shut off. The present investigation involved storing 4k x 1 bit maps every second during 1 min ion exposures at low flux rates of 10 3 ions/cm 2 -s in order to reduce the chance of two sequential ions upsetting adjacent bits. The data were analyzed for the presence of adjacent upset bit locations in the physical memory plane, which were previously defined to constitute multiple upsets. Improvement in the time resolution of these measurements has provided more accurate estimates of multiple upsets. The results indicate that the percentage of multiples decreased from a high of 17% in the previous experiment to less than 1% for this new experimental technique. Consecutive double and triple upsets (reversals of bits) were detected. These were caused by sequential ions hitting the same bit, with one or two reversals of state occurring in a 1-min run. In addition to these results, a status review for these same parts covering 3.5 years of imprint damage recovery is also presented

Cross Institutional Cooperation on a Shared Bit Repository

DEFF Research Database (Denmark)

Zierau, Eld; Kejser, Ulla Bøgvad

2013-01-01

This paper explores how independent institutions, such as archives and libraries, can cooperate on managing a shared bit repository with bit preservation, in order to use their resources for preservation in a more cost-effective way. It uses the OAIS Reference Model to provide a framework...... for systematically analysing institutions technical and organisational requirements for a remote bit repository. Instead of viewing a bit repository simply as Archival Storage for the institutions repositories, we argue for viewing it as consisting of a subset of functions from all entities defined by the OAIS...... Reference Model. The work is motivated by and used in a current Danish feasibility study for establishing a national bit repository. The study revealed that depending on their missions and the collections they hold, the institutions have varying requirements e.g. for bit safety, accessibility...

Cross Institutional Cooperation on a Shared Bit Repository

DEFF Research Database (Denmark)

Zierau, Eld; Kejser, Ulla Bøgvad

2010-01-01

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...

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.

Adaptive bit plane quadtree-based block truncation coding for image compression

Science.gov (United States)

Li, Shenda; Wang, Jin; Zhu, Qing

2018-04-01

Block truncation coding (BTC) is a fast image compression technique applied in spatial domain. Traditional BTC and its variants mainly focus on reducing computational complexity for low bit rate compression, at the cost of lower quality of decoded images, especially for images with rich texture. To solve this problem, in this paper, a quadtree-based block truncation coding algorithm combined with adaptive bit plane transmission is proposed. First, the direction of edge in each block is detected using Sobel operator. For the block with minimal size, adaptive bit plane is utilized to optimize the BTC, which depends on its MSE loss encoded by absolute moment block truncation coding (AMBTC). Extensive experimental results show that our method gains 0.85 dB PSNR on average compare to some other state-of-the-art BTC variants. So it is desirable for real time image compression applications.

Inter-track interference mitigation with two-dimensional variable equalizer for bit patterned media recording

Directory of Open Access Journals (Sweden)

Yao Wang

2017-05-01

Full Text Available The increased track density in bit patterned media recording (BPMR causes increased inter-track interference (ITI, which degrades the bit error rate (BER performance. In order to mitigate the effect of the ITI, signals from multiple tracks can be equalized by a 2D equalizer with 1D target. Usually, the 2D fixed equalizer coefficients are obtained by using a pseudo-random bit sequence (PRBS for training. In this study, a 2D variable equalizer is proposed, where various sets of 2D equalizer coefficients are predetermined and stored for different ITI patterns besides the usual PRBS training. For data detection, as the ITI patterns are unknown in the first global iteration, the main and adjacent tracks are equalized with the conventional 2D fixed equalizer, detected with Bahl-Cocke-Jelinek-Raviv (BCJR detector and decoded with low-density parity-check (LDPC decoder. Then using the estimated bit information from main and adjacent tracks, the ITI pattern for each island of the main track can be estimated and the corresponding 2D variable equalizers are used to better equalize the bits on the main track. This process is executed iteratively by feeding back the main track information. Simulation results indicate that for both single-track and two-track detection, the proposed 2D variable equalizer can achieve better BER and frame error rate (FER compared to that with the 2D fixed equalizer.

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 ...

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

LDPC product coding scheme with extrinsic information for bit patterned media recoding

Science.gov (United States)

Jeong, Seongkwon; Lee, Jaejin

2017-05-01

Since the density limit of the current perpendicular magnetic storage system will soon be reached, bit patterned media recording (BPMR) is a promising candidate for the next generation storage system to achieve an areal density beyond 1 Tb/in2. Each recording bit is stored in a fabricated magnetic island and the space between the magnetic islands is nonmagnetic in BPMR. To approach recording densities of 1 Tb/in2, the spacing of the magnetic islands must be less than 25 nm. Consequently, severe inter-symbol interference (ISI) and inter-track interference (ITI) occur. ITI and ISI degrade the performance of BPMR. In this paper, we propose a low-density parity check (LDPC) product coding scheme that exploits extrinsic information for BPMR. This scheme shows an improved bit error rate performance compared to that in which one LDPC code is used.

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.)

Efficient Hybrid Watermarking Scheme for Security and Transmission Bit Rate Enhancement of 3D Color-Plus-Depth Video Communication

Science.gov (United States)

El-Shafai, W.; El-Rabaie, S.; El-Halawany, M.; Abd El-Samie, F. E.

2018-03-01

Three-Dimensional Video-plus-Depth (3DV + D) comprises diverse video streams captured by different cameras around an object. Therefore, there is a great need to fulfill efficient compression to transmit and store the 3DV + D content in compressed form to attain future resource bounds whilst preserving a decisive reception quality. Also, the security of the transmitted 3DV + D is a critical issue for protecting its copyright content. This paper proposes an efficient hybrid watermarking scheme for securing the 3DV + D transmission, which is the homomorphic transform based Singular Value Decomposition (SVD) in Discrete Wavelet Transform (DWT) domain. The objective of the proposed watermarking scheme is to increase the immunity of the watermarked 3DV + D to attacks and achieve adequate perceptual quality. Moreover, the proposed watermarking scheme reduces the transmission-bandwidth requirements for transmitting the color-plus-depth 3DV over limited-bandwidth wireless networks through embedding the depth frames into the color frames of the transmitted 3DV + D. Thus, it saves the transmission bit rate and subsequently it enhances the channel bandwidth-efficiency. The performance of the proposed watermarking scheme is compared with those of the state-of-the-art hybrid watermarking schemes. The comparisons depend on both the subjective visual results and the objective results; the Peak Signal-to-Noise Ratio (PSNR) of the watermarked frames and the Normalized Correlation (NC) of the extracted watermark frames. Extensive simulation results on standard 3DV + D sequences have been conducted in the presence of attacks. The obtained results confirm that the proposed hybrid watermarking scheme is robust in the presence of attacks. It achieves not only very good perceptual quality with appreciated PSNR values and saving in the transmission bit rate, but also high correlation coefficient values in the presence of attacks compared to the existing hybrid watermarking schemes.

A facile approach for screening isolated nanomagnetic behavior for bit-patterned media

International Nuclear Information System (INIS)

Thiyagarajah, Naganivetha; Ng, Vivian; Asbahi, Mohamed; Yakovlev, Nikolai L; Yang, Joel K W; Wong, Rick T J; Low, Kendrick W M

2014-01-01

Bit-patterned media (BPM) fabricated by the direct deposition of magnetic material onto prepatterned arrays of nanopillars is a promising approach for increasing magnetic recording of areal density. One of the key challenges of this approach is to identify and control the magnetic interaction between the bits (on top of the nanopillars) and the trench material between the pillars. Using independent techniques, including magnetic force microscopy, the variable-angle magneto-optic Kerr effect, and remanence curves, we were able to determine the presence and relative intensities of exchange and dipolar interactions in Co-Pd multilayer-based BPM fabricated by direct deposition. We found that for pitches of 30 nm or less, there were negligible exchange interactions, and the bits were found to be magnetically isolated. As we move to higher densities, the absence of exchange interactions indicates that direct deposition is a promising approach to BPM fabrication. (papers)

Bit Plane Coding based Steganography Technique for JPEG2000 Images and Videos

Directory of Open Access Journals (Sweden)

Geeta Kasana

2016-02-01

Full Text Available In this paper, a Bit Plane Coding (BPC based steganography technique for JPEG2000 images and Motion JPEG2000 video is proposed. Embedding in this technique is performed in the lowest significant bit planes of the wavelet coefficients of a cover image. In JPEG2000 standard, the number of bit planes of wavelet coefficients to be used in encoding is dependent on the compression rate and are used in Tier-2 process of JPEG2000. In the proposed technique, Tier-1 and Tier-2 processes of JPEG2000 and Motion JPEG2000 are executed twice on the encoder side to collect the information about the lowest bit planes of all code blocks of a cover image, which is utilized in embedding and transmitted to the decoder. After embedding secret data, Optimal Pixel Adjustment Process (OPAP is applied on stego images to enhance its visual quality. Experimental results show that proposed technique provides large embedding capacity and better visual quality of stego images than existing steganography techniques for JPEG2000 compressed images and videos. Extracted secret image is similar to the original secret image.

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...

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.

LDPC product coding scheme with extrinsic information for bit patterned media recoding

Directory of Open Access Journals (Sweden)

Seongkwon Jeong

2017-05-01

Full Text Available Since the density limit of the current perpendicular magnetic storage system will soon be reached, bit patterned media recording (BPMR is a promising candidate for the next generation storage system to achieve an areal density beyond 1 Tb/in2. Each recording bit is stored in a fabricated magnetic island and the space between the magnetic islands is nonmagnetic in BPMR. To approach recording densities of 1 Tb/in2, the spacing of the magnetic islands must be less than 25 nm. Consequently, severe inter-symbol interference (ISI and inter-track interference (ITI occur. ITI and ISI degrade the performance of BPMR. In this paper, we propose a low-density parity check (LDPC product coding scheme that exploits extrinsic information for BPMR. This scheme shows an improved bit error rate performance compared to that in which one LDPC code is used.

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

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.

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)

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.

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.

Cross-Layer Resource Allocation for Variable Bit Rate Multiclass Services in a Multirate Multicarrier DS-CDMA Network

Directory of Open Access Journals (Sweden)

Kee-Chaing Chua

2005-02-01

Full Text Available An approximate analytical formulation of the resource allocation problem for handling variable bit rate multiclass services in a cellular round-robin carrier-hopping multirate multicarrier direct-sequence code-division multiple-access (MC-DS-CDMA system is presented. In this paper, all grade-of-service (GoS or quality-of-service (QoS requirements at the connection level, packet level, and link layer are satisfied simultaneously in the system, instead of being satisfied at the connection level or at the link layer only. The analytical formulation shows how the GoS/QoS in the different layers are intertwined across the layers. A novelty of this paper is that the outages in the subcarriers are minimized by spreading the subcarriers' signal-to-interference ratio evenly among all the subcarriers by using a dynamic round-robin carrier-hopping allocation scheme. A complete sharing (CS scheme with guard capacity is used for the resource sharing policy at the connection level based on the mean rates of the connections. Numerical results illustrate that significant gain in the system utilization is achieved through the joint coupling of connection/packet levels and link layer.

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.

Synchronization of random bit generators based on coupled chaotic lasers and application to cryptography.

Science.gov (United States)

Kanter, Ido; Butkovski, Maria; Peleg, Yitzhak; Zigzag, Meital; Aviad, Yaara; Reidler, Igor; Rosenbluh, Michael; Kinzel, Wolfgang

2010-08-16

Random bit generators (RBGs) constitute an important tool in cryptography, stochastic simulations and secure communications. The later in particular has some difficult requirements: high generation rate of unpredictable bit strings and secure key-exchange protocols over public channels. Deterministic algorithms generate pseudo-random number sequences at high rates, however, their unpredictability is limited by the very nature of their deterministic origin. Recently, physical RBGs based on chaotic semiconductor lasers were shown to exceed Gbit/s rates. Whether secure synchronization of two high rate physical RBGs is possible remains an open question. Here we propose a method, whereby two fast RBGs based on mutually coupled chaotic lasers, are synchronized. Using information theoretic analysis we demonstrate security against a powerful computational eavesdropper, capable of noiseless amplification, where all parameters are publicly known. The method is also extended to secure synchronization of a small network of three RBGs.

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.

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.

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 ¡ ...

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.

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.

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...

Design of a 12-bit 80MS/s pipeline analog-to-digital converter for PLC-VDSL applications

Science.gov (United States)

Ruiz-Amaya, Jesus; Delgado-Restituto, Manuel; Fernandez-Bootello, Juan F.; de la Rosa, Jose M.

2005-06-01

This paper describes the design of a 12-bit 80MS/s pipeline Analog-to-Digital converter implemented in 0.13mm CMOS logic technology. The design has been computer-aided by a developed toolbox for the simulation, synthesis and verification of Nyquist-Rate Analog-to-Digital and Digital-to-Analog Converters in MATLAB. The embedded simulator uses SIMULINK C-coded S-functions to model all required subcircuits including their main error mechanisms. This approach allows to drastically speed up the simulation CPU-time and makes the proposed tool an advantageous alternative for fast exploration of requirements and as a design validation tool. The converter is based on a 10-stage pipeline preceded by a sample/hold with bootstrapping technique. Each stage gives 1.5 effective bits, except for the first one which provides 2.5 effective bits to improve linearity. The Analog-to-Digital architecture uses redundant bits for digital correction, it is planned to be implemented without using calibration and employs a subranging pipeline look-ahead technique to increase speed. Substrate biased MOSFETs in the depletion region are used as capacitors, linearized by a series compensation. Simulation results show that the Multi-Tone Power Ratio is higher than 56dB for several DMT test signals and the estimated Signal-to-Noise Ratio yield is supposed to be better than 62 dB from DC to Nyquist frequency. The converter dissipates less than 150mW from a 3.3V supply and occupies less than 4 mm2 die area. The results have been checked with all process corners from -40° to 85° and power supply from 3V to 3.6V.

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

Analysis of simultaneous multi-bit induced by a cosmic ray for onboard memory

International Nuclear Information System (INIS)

Ono, Takashi; Mori, Masato

1987-01-01

Accompanying the development of intelligent onboard equipment using high density memories, the soft-error phenomenon, which is the bit upset induced by a cosmic ray, must be investigated. Especially, the simultaneous multi-bit error (SME) induced by a cosmic ray negligible on earth becomes remarkable in space use. This paper entimates the SME occurrence rate of memory chip by computer simulations and describes the results of the SME experiments using a cyclotron. The computer simulation and experiment results confirm the SME occurrence and show that layout of memory cells is important for the probability of SME occurrence. (author)

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

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.

A 10-bit 100 MSamples/s BiCMOS D/A Converter

DEFF Research Database (Denmark)

Jørgensen, Ivan Herald Holger; Tunheim, Svein Anders

1997-01-01

This paper presents a 10-bit Digital-to-Analogue Converter (DAC) based on the current steering principle. The DAC is processed in a 0.8 micron BiCMOS process and is designed to operate at a sampling rate of 100MSamples/s. The DAC is intended for applications using direct digital synthesis...

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...

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...

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.

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.

Bit-level quantum color image encryption scheme with quantum cross-exchange operation and hyper-chaotic system

Science.gov (United States)

Zhou, Nanrun; Chen, Weiwei; Yan, Xinyu; Wang, Yunqian

2018-06-01

In order to obtain higher encryption efficiency, a bit-level quantum color image encryption scheme by exploiting quantum cross-exchange operation and a 5D hyper-chaotic system is designed. Additionally, to enhance the scrambling effect, the quantum channel swapping operation is employed to swap the gray values of corresponding pixels. The proposed color image encryption algorithm has larger key space and higher security since the 5D hyper-chaotic system has more complex dynamic behavior, better randomness and unpredictability than those based on low-dimensional hyper-chaotic systems. Simulations and theoretical analyses demonstrate that the presented bit-level quantum color image encryption scheme outperforms its classical counterparts in efficiency and security.

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.

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.

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.

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.)

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.

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.

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 ...

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.

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).

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.

MEKANISME SEGMENTASI LAJU BIT PADA DYNAMIC ADAPTIVE STREAMING OVER HTTP (DASH UNTUK APLIKASI VIDEO STREAMING

Directory of Open Access Journals (Sweden)

Muhammad Audy Bazly

2015-12-01

Full Text Available This paper aims to analyze Internet-based streaming video service in the communication media with variable bit rates. The proposed scheme on Dynamic Adaptive Streaming over HTTP (DASH using the internet network that adapts to the protocol Hyper Text Transfer Protocol (HTTP. DASH technology allows a video in the video segmentation into several packages that will distreamingkan. DASH initial stage is to compress the video source to lower the bit rate video codec uses H.26. Video compressed further in the segmentation using MP4Box generates streaming packets with the specified duration. These packages are assembled into packets in a streaming media format Presentation Description (MPD or known as MPEG-DASH. Streaming video format MPEG-DASH run on a platform with the player bitdash teritegrasi bitcoin. With this scheme, the video will have several variants of the bit rates that gave rise to the concept of scalability of streaming video services on the client side. The main target of the mechanism is smooth the MPEG-DASH streaming video display on the client. The simulation results show that the scheme based scalable video streaming MPEG- DASH able to improve the quality of image display on the client side, where the procedure bufering videos can be made constant and fine for the duration of video views

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.

Particle-induced bit errors in high performance fiber optic data links for satellite data management

International Nuclear Information System (INIS)

Marshall, P.W.; Carts, M.A.; Dale, C.J.; LaBel, K.A.

1994-01-01

Experimental test methods and analysis tools are demonstrated to assess particle-induced bit errors on fiber optic link receivers for satellites. Susceptibility to direct ionization from low LET particles is quantified by analyzing proton and helium ion data as a function of particle LET. Existing single event analysis approaches are shown to apply, with appropriate modifications, to the regime of temporally (rather than spatially) distributed bits, even though the sensitivity to single events exceeds conventional memory technologies by orders of magnitude. The cross-section LET dependence follows a Weibull distribution at data rates from 200 to 1,000 Mbps and at various incident optical power levels. The LET threshold for errors is shown, through both experiment and modeling, to be 0 in all cases. The error cross-section exhibits a strong inverse dependence on received optical power in the LET range where most orbital single events would occur, thus indicating that errors can be minimized by operating links with higher incident optical power. Also, an analytic model is described which incorporates the appropriate physical characteristics of the link as well as the optical and receiver electrical characteristics. Results indicate appropriate steps to assure suitable link performance even in severe particle orbits

SOLAR TRACKER CERDAS DAN MURAH BERBASIS MIKROKONTROLER 8 BIT ATMega8535

Directory of Open Access Journals (Sweden)

I Wayan Sutaya

2016-08-01

Full Text Available 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 bit sebagai otak utama pada penelitian ini menjadikan produk ini berbiaya rendah. Pengujian yang dilakukan menunjukkan bahwa solar tracker cerdas dibandingkan dengan solar tracker biasa mempunyai perbedaan konsumsi daya baterai yang sangat signifikan yaitu terjadi penghematan sebesar 85 %. Besar penghematan konsumsi daya ini tentunya bukan sebuah angka konstan melainkan tergantung seberapa besar noise yang dikenakan pada alat solar tracker. Untuk sebuah perlakuan yang sama, maka semakin besar noise semakin besar pula perbedaan penghematan konsumsi daya pada solar tracker yang cerdas. Kata-kata kunci: solar tracker, filter digital, mikrokontroler 8 bit, konsumsi daya Abstract This research had made a prototype of smart solar tracker product based on microcontroller AVR 8 bit. The solar tracker used digital filter IIR (Infinite Impulse Response on its software. Filter programming needs 32 bit multiplication but the processor inside of the microcontroller that used in this research is 8 bit. This multiplication is only can be solved on microcontroller 8 bit by using assembly language in programming. The language is a hardware level language. The smart solar tracker using the microcontroller 8 bit as a main brain in this research made the product had a low cost. The test results show that the comparison in saving of baterai power consumption between the smart solar tracker and the normal one is 85 %. The percentage of the saving indubitably is not a constant

Methods to ensure optimal off-bottom and drill bit distance under pellet impact drilling

Science.gov (United States)

Kovalyov, A. V.; Isaev, Ye D.; Vagapov, A. R.; Urnish, V. V.; Ulyanova, O. S.

2016-09-01

The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rock for various purposes. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The paper presents the survey of methods ensuring an optimal off-bottom and a drill bit distance. The analysis of methods shows that the issue is topical and requires further research.

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.

Bit rates in audio source coding

NARCIS (Netherlands)

Veldhuis, Raymond N.J.

1992-01-01

The goal is to introduce and solve the audio coding optimization problem. Psychoacoustic results such as masking and excitation pattern models are combined with results from rate distortion theory to formulate the audio coding optimization problem. The solution of the audio optimization problem is a

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

Detection and Symbol Synchronization for Multiple-bit Per Photon Optical Communications

Science.gov (United States)

Marshall, W. K.

1985-01-01

Methods of detection and synchronization in a highly efficient direct detection optical communication system are reported. Results of measurements on this moderate-rate demonstration system capable of transmitting 2.5 bits/detected photon in low-background situations indicate that symbol slot synchronization is not a problem, and that a simple symbol detection scheme is adequate for this situation. This system is a candidate for interplanetary optical communications.

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.

Scintillation and bit error rate analysis of a phase-locked partially coherent flat-topped array laser beam in oceanic turbulence.

Science.gov (United States)

Yousefi, Masoud; Kashani, Fatemeh Dabbagh; Golmohammady, Shole; Mashal, Ahmad

2017-12-01

In this paper, the performance of underwater wireless optical communication (UWOC) links, which is made up of the partially coherent flat-topped (PCFT) array laser beam, has been investigated in detail. Providing high power, array laser beams are employed to increase the range of UWOC links. For characterization of the effects of oceanic turbulence on the propagation behavior of the considered beam, using the extended Huygens-Fresnel principle, an analytical expression for cross-spectral density matrix elements and a semi-analytical one for fourth-order statistical moment have been derived. Then, based on these expressions, the on-axis scintillation index of the mentioned beam propagating through weak oceanic turbulence has been calculated. Furthermore, in order to quantify the performance of the UWOC link, the average bit error rate (BER) has also been evaluated. The effects of some source factors and turbulent ocean parameters on the propagation behavior of the scintillation index and the BER have been studied in detail. The results of this investigation indicate that in comparison with the Gaussian array beam, when the source size of beamlets is larger than the first Fresnel zone, the PCFT array laser beam with the higher flatness order is found to have a lower scintillation index and hence lower BER. Specifically, in the sense of scintillation index reduction, using the PCFT array laser beams has a considerable benefit in comparison with the single PCFT or Gaussian laser beams and also Gaussian array beams. All the simulation results of this paper have been shown by graphs and they have been analyzed in detail.

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.

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.

Hybrid Data Hiding Scheme Using Right-Most Digit Replacement and Adaptive Least Significant Bit for Digital Images

Directory of Open Access Journals (Sweden)

Mehdi Hussain

2016-05-01

Full Text Available The goal of image steganographic methods considers three main key issues: high embedding capacity, good visual symmetry/quality, and security. In this paper, a hybrid data hiding method combining the right-most digit replacement (RMDR with an adaptive least significant bit (ALSB is proposed to provide not only high embedding capacity but also maintain a good visual symmetry. The cover-image is divided into lower texture (symmetry patterns and higher texture (asymmetry patterns areas and these textures determine the selection of RMDR and ALSB methods, respectively, according to pixel symmetry. This paper has three major contributions. First, the proposed hybrid method enhanced the embedding capacity due to efficient ALSB utilization in the higher texture areas of cover images. Second, the proposed hybrid method maintains the high visual quality because RMDR has the closest selection process to generate the symmetry between stego and cover pixels. Finally, the proposed hybrid method is secure against statistical regular or singular (RS steganalysis and pixel difference histogram steganalysis because RMDR is capable of evading the risk of RS detection attacks due to pixel digits replacement instead of bits. Extensive experimental tests (over 1500+ cover images are conducted with recent least significant bit (LSB-based hybrid methods and it is demonstrated that the proposed hybrid method has a high embedding capacity (800,019 bits while maintaining good visual symmetry (39.00% peak signal-to-noise ratio (PSNR.

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

A 10-bit 200-kS/s SAR ADC IP core for a touch screen SoC

International Nuclear Information System (INIS)

Tong Xingyuan; Yang Yintang; Zhu Zhangming; Sheng Wenfang

2010-01-01

Based on a 5 MSBs (most-significant-bits)-plus-5 LSBs (least-significant-bits) C-R hybrid D/A conversion and low-offset pseudo-differential comparison approach, with capacitor array axially symmetric layout topology and resistor string low gradient mismatch placement method, an 8-channel 10-bit 200-kS/s SAR ADC (successive-approximation-register analog-to-digital converter) IP core for a touch screen SoC (system-on-chip) is implemented in a 0.18 μm 1P5M CMOS logic process. Design considerations for the touch screen SAR ADC are included. With a 1.8 V power supply, the DNL (differential non-linearity) and INL (integral non-linearity) of this converter are measured to be about 0.32 LSB and 0.81 LSB respectively. With an input frequency of 91 kHz at 200-kS/s sampling rate, the spurious-free dynamic range and effective-number-of-bits are measured to be 63.2 dB and 9.15 bits respectively, and the power is about 136 μW. This converter occupies an area of about 0.08 mm 2 . The design results show that it is very suitable for touch screen SoC applications. (semiconductor integrated circuits)

Rate-distortion optimization for compressive video sampling

Science.gov (United States)

Liu, Ying; Vijayanagar, Krishna R.; Kim, Joohee

2014-05-01

The recently introduced compressed sensing (CS) framework enables low complexity video acquisition via sub- Nyquist rate sampling. In practice, the resulting CS samples are quantized and indexed by finitely many bits (bit-depth) for transmission. In applications where the bit-budget for video transmission is constrained, rate- distortion optimization (RDO) is essential for quality video reconstruction. In this work, we develop a double-level RDO scheme for compressive video sampling, where frame-level RDO is performed by adaptively allocating the fixed bit-budget per frame to each video block based on block-sparsity, and block-level RDO is performed by modelling the block reconstruction peak-signal-to-noise ratio (PSNR) as a quadratic function of quantization bit-depth. The optimal bit-depth and the number of CS samples are then obtained by setting the first derivative of the function to zero. In the experimental studies the model parameters are initialized with a small set of training data, which are then updated with local information in the model testing stage. Simulation results presented herein show that the proposed double-level RDO significantly enhances the reconstruction quality for a bit-budget constrained CS video transmission system.

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

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

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

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.

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...

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.

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.

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...

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.

Information rates of probabilistically shaped coded modulation for a multi-span fiber-optic communication system with 64QAM

Science.gov (United States)

Fehenberger, Tobias

2018-02-01

This paper studies probabilistic shaping in a multi-span wavelength-division multiplexing optical fiber system with 64-ary quadrature amplitude modulation (QAM) input. In split-step fiber simulations and via an enhanced Gaussian noise model, three figures of merit are investigated, which are signal-to-noise ratio (SNR), achievable information rate (AIR) for capacity-achieving forward error correction (FEC) with bit-metric decoding, and the information rate achieved with low-density parity-check (LDPC) FEC. For the considered system parameters and different shaped input distributions, shaping is found to decrease the SNR by 0.3 dB yet simultaneously increases the AIR by up to 0.4 bit per 4D-symbol. The information rates of LDPC-coded modulation with shaped 64QAM input are improved by up to 0.74 bit per 4D-symbol, which is larger than the shaping gain when considering AIRs. This increase is attributed to the reduced coding gap of the higher-rate code that is used for decoding the nonuniform QAM input.

Optimized bit extraction using distortion modeling in the scalable extension of H.264/AVC.

Science.gov (United States)

Maani, Ehsan; Katsaggelos, Aggelos K

2009-09-01

The newly adopted scalable extension of H.264/AVC video coding standard (SVC) demonstrates significant improvements in coding efficiency in addition to an increased degree of supported scalability relative to the scalable profiles of prior video coding standards. Due to the complicated hierarchical prediction structure of the SVC and the concept of key pictures, content-aware rate adaptation of SVC bit streams to intermediate bit rates is a nontrivial task. The concept of quality layers has been introduced in the design of the SVC to allow for fast content-aware prioritized rate adaptation. However, existing quality layer assignment methods are suboptimal and do not consider all network abstraction layer (NAL) units from different layers for the optimization. In this paper, we first propose a technique to accurately and efficiently estimate the quality degradation resulting from discarding an arbitrary number of NAL units from multiple layers of a bitstream by properly taking drift into account. Then, we utilize this distortion estimation technique to assign quality layers to NAL units for a more efficient extraction. Experimental results show that a significant gain can be achieved by the proposed scheme.

A Model of Computation for Bit-Level Concurrent Computing and Programming: APEC

Science.gov (United States)

Ajiro, Takashi; Tsuchida, Kensei

A concurrent model of computation and a language based on the model for bit-level operation are useful for developing asynchronous and concurrent programs compositionally, which frequently use bit-level operations. Some examples are programs for video games, hardware emulation (including virtual machines), and signal processing. However, few models and languages are optimized and oriented to bit-level concurrent computation. We previously developed a visual programming language called A-BITS for bit-level concurrent programming. The language is based on a dataflow-like model that computes using processes that provide serial bit-level operations and FIFO buffers connected to them. It can express bit-level computation naturally and develop compositionally. We then devised a concurrent computation model called APEC (Asynchronous Program Elements Connection) for bit-level concurrent computation. This model enables precise and formal expression of the process of computation, and a notion of primitive program elements for controlling and operating can be expressed synthetically. Specifically, the model is based on a notion of uniform primitive processes, called primitives, that have three terminals and four ordered rules at most, as well as on bidirectional communication using vehicles called carriers. A new notion is that a carrier moving between two terminals can briefly express some kinds of computation such as synchronization and bidirectional communication. The model's properties make it most applicable to bit-level computation compositionally, since the uniform computation elements are enough to develop components that have practical functionality. Through future application of the model, our research may enable further research on a base model of fine-grain parallel computer architecture, since the model is suitable for expressing massive concurrency by a network of primitives.

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.

Bounds on Minimum Energy per Bit for Optical Wireless Relay Channels

Directory of Open Access Journals (Sweden)

A. D. Raza

2014-09-01

Full Text Available An optical wireless relay channel (OWRC is the classical three node network consisting of source, re- lay and destination nodes with optical wireless connectivity. The channel law is assumed Gaussian. This paper studies the bounds on minimum energy per bit required for reliable communication over an OWRC. It is shown that capacity of an OWRC is concave and energy per bit is monotonically increasing in square of the peak optical signal power, and consequently the minimum energy per bit is inversely pro- portional to the square root of asymptotic capacity at low signal to noise ratio. This has been used to develop upper and lower bound on energy per bit as a function of peak signal power, mean to peak power ratio, and variance of channel noise. The upper and lower bounds on minimum energy per bit derived in this paper correspond respectively to the decode and forward lower bound and the min-max cut upper bound on OWRC capacity

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.

Optimization of rock-bit life based on bearing failure criteria

International Nuclear Information System (INIS)

Feav, M.J.; Thorogood, J.L.; Whelehan, O.P.; Williamson, H.S.

1992-01-01

This paper reports that recent advances in rock-bit seal technology have allowed greater predictability of bearing life. Cone loss following bearing failure incurs costs related to remedial activities. A risk analysis approach, incorporating bearing-life relationships and the inter-dependence of drilling events, is used to formulate a bit-run cost-optimization method. The procedure enables a choice to be made between elastomeric and metal seals on a lowest-replacement-cost basis. The technique also provides a formal method for assessing the opportunity cost for using a device to detect bit-bearing failures downhole

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

FastBit: an efficient indexing technology for accelerating data-intensive science

International Nuclear Information System (INIS)

Wu Kesheng

2005-01-01

FastBit is a software tool for searching large read-only datasets. It organizes user data in a column-oriented structure which is efficient for on-line analytical processing (OLAP), and utilizes compressed bitmap indices to further speed up query processing. Analyses have proven the compressed bitmap index used in FastBit to be theoretically optimal for onedimensional queries. Compared with other optimal indexing methods, bitmap indices are superior because they can be efficiently combined to answer multi-dimensional queries whereas other optimal methods can not. In this paper, we first describe the searching capability of FastBit, then briefly highlight two applications that make extensive use of FastBit, namely Grid Collector and DEX

FastBit: An Efficient Indexing Technology For AcceleratingData-Intensive Science

Energy Technology Data Exchange (ETDEWEB)

Wu, Kesheng

2005-06-27

FastBit is a software tool for searching large read-only data sets. It organizes user data in a column-oriented structure which is efficient for on-line analytical processing (OLAP), and utilizes compressed bitmap indices to further speed up query processing. Analyses have proven the compressed bitmap index used in FastBit to be theoretically optimal for one-dimensional queries. Compared with other optimal indexing methods, bitmap indices are superior because they can be efficiently combined to answer multi-dimensional queries whereas other optimal methods cannot. In this paper, we first describe the searching capability of FastBit, then briefly highlight two applications that make extensive use of FastBit, namely Grid Collector and DEX.

FastBit: an efficient indexing technology for accelerating data-intensive science

Science.gov (United States)

Wu, Kesheng

2005-01-01

FastBit is a software tool for searching large read-only datasets. It organizes user data in a column-oriented structure which is efficient for on-line analytical processing (OLAP), and utilizes compressed bitmap indices to further speed up query processing. Analyses have proven the compressed bitmap index used in FastBit to be theoretically optimal for onedimensional queries. Compared with other optimal indexing methods, bitmap indices are superior because they can be efficiently combined to answer multi-dimensional queries whereas other optimal methods can not. In this paper, we first describe the searching capability of FastBit, then briefly highlight two applications that make extensive use of FastBit, namely Grid Collector and DEX.

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

High Rate Digital Demodulator ASIC

Science.gov (United States)

Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew

1998-01-01

The architecture of High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation in other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA's Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an over-view of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

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....

Detection of LSB+/-1 steganography based on co-occurrence matrix and bit plane clipping

Science.gov (United States)

Abolghasemi, Mojtaba; Aghaeinia, Hassan; Faez, Karim; Mehrabi, Mohammad Ali

2010-01-01

Spatial LSB+/-1 steganography changes smooth characteristics between adjoining pixels of the raw image. We present a novel steganalysis method for LSB+/-1 steganography based on feature vectors derived from the co-occurrence matrix in the spatial domain. We investigate how LSB+/-1 steganography affects the bit planes of an image and show that it changes more least significant bit (LSB) planes of it. The co-occurrence matrix is derived from an image in which some of its most significant bit planes are clipped. By this preprocessing, in addition to reducing the dimensions of the feature vector, the effects of embedding were also preserved. We compute the co-occurrence matrix in different directions and with different dependency and use the elements of the resulting co-occurrence matrix as features. This method is sensitive to the data embedding process. We use a Fisher linear discrimination (FLD) classifier and test our algorithm on different databases and embedding rates. We compare our scheme with the current LSB+/-1 steganalysis methods. It is shown that the proposed scheme outperforms the state-of-the-art methods in detecting the LSB+/-1 steganographic method for grayscale images.

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...

Time-space modal logic for verification of bit-slice circuits

Science.gov (United States)

Hiraishi, Hiromi

1996-03-01

The major goal of this paper is to propose a new modal logic aiming at formal verification of bit-slice circuits. The new logic is called as time-space modal logic and its major feature is that it can handle two transition relations: one for time transition and the other for space transition. As for a verification algorithm, a symbolic model checking algorithm of the new logic is shown. This could be applicable to verification of bit-slice microprocessor of infinite bit width and 1D systolic array of infinite length. A simple benchmark result shows the effectiveness of the proposed approach.

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.

Klasifikasi Bit-Plane Noise untuk Penyisipan Pesan pada Teknik Steganography BPCS Menggunakan Fuzzy Inference Sistem Mamdani

Directory of Open Access Journals (Sweden)

Rahmad Hidayat

2015-04-01

Full Text Available Bit-Plane Complexity Segmentation (BPCS is a fairly new steganography technique. The most important process in BPCS is the calculation of complexity value of a bit-plane. The bit-plane complexity is calculated by looking at the amount of bit changes contained in a bit-plane. If a bit-plane has a high complexity, the bi-plane is categorized as a noise bit-plane that does not contain valuable information on the image. Classification of the bit-plane using the set cripst set (noise/not is not fair, where a little difference of the value will significantly change the status of the bit-plane. The purpose of this study is to apply the principles of fuzzy sets to classify the bit-plane into three sets that are informative, partly informative, and the noise region. Classification of the bit-plane into a fuzzy set is expected to classify the bit-plane in a more objective approach and ultimately message capacity of the images can be improved by using the Mamdani fuzzy inference to take decisions which bit-plane will be replaced with a message based on the classification of bit-plane and the size of the message that will be inserted. This research is able to increase the capability of BPCS steganography techniques to insert a message in bit-pane with more precise so that the container image quality would be better. It can be seen that the PSNR value of original image and stego-image is only slightly different.

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

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

The Effects of Bit Wear on Respirable Silica Dust, Noise and Productivity: A Hammer Drill Bench Study.

Science.gov (United States)

Carty, Paul; Cooper, Michael R; Barr, Alan; Neitzel, Richard L; Balmes, John; Rempel, David

2017-07-01

Hammer drills are used extensively in commercial construction for drilling into concrete for tasks including rebar installation for structural upgrades and anchor bolt installation. This drilling task can expose workers to respirable silica dust and noise. The aim of this pilot study was to evaluate the effects of bit wear on respirable silica dust, noise, and drilling productivity. Test bits were worn to three states by drilling consecutive holes to different cumulative drilling depths: 0, 780, and 1560 cm. Each state of bit wear was evaluated by three trials (nine trials total). For each trial, an automated laboratory test bench system drilled 41 holes 1.3 cm diameter, and 10 cm deep into concrete block at a rate of one hole per minute using a commercially available hammer drill and masonry bits. During each trial, dust was continuously captured by two respirable and one inhalable sampling trains and noise was sampled with a noise dosimeter. The room was thoroughly cleaned between trials. When comparing results for the sharp (0 cm) versus dull bit (1560 cm), the mean respirable silica increased from 0.41 to 0.74 mg m-3 in sampler 1 (P = 0.012) and from 0.41 to 0.89 mg m-3 in sampler 2 (P = 0.024); levels above the NIOSH recommended exposure limit of 0.05 mg m-3. Likewise, mean noise levels increased from 112.8 to 114.4 dBA (P < 0.00001). Drilling productivity declined with increasing wear from 10.16 to 7.76 mm s-1 (P < 0.00001). Increasing bit wear was associated with increasing respirable silica dust and noise and reduced drilling productivity. The levels of dust and noise produced by these experimental conditions would require dust capture, hearing protection, and possibly respiratory protection. The findings support the adoption of a bit replacement program by construction contractors. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

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

Feasibility of bit patterned media for HAMR at 5 Tb/in{sup 2}

Energy Technology Data Exchange (ETDEWEB)

Wang, Sumei, E-mail: wang3936@umn.edu; Ghoreyshi, Ali; Victora, R. H. [MINT, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

2015-05-07

We have investigated the feasibility of BPM for HAMR via Finite Difference Time Domain and atomistic simulation and we have substantiated the feasibility of 5 Tb/in{sup 2} with two filling factors 25% and 56% even when the maximum on-track bit temperature is below the Curie temperature. The success of this underheated switching is attributed to sufficiently low anisotropy instead of reduction of Curie temperature. The temperature gradient in the cross-track direction is almost doubled if the optical head width is reduced by half, indicating the possibility of higher areal densities. Moreover, contrary to continuous media, we also found that the power absorption peaks at the bottom of the bit patterned FePt when the media is illuminated from above, which is probably due to stronger coupling there between FePt and the surrounding materials.

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...

A 14-bit 50 MS/s sample-and-hold circuit for pipelined ADC

International Nuclear Information System (INIS)

Yue Sen; Zhao Yiqiang; Pang Ruilong; Sheng Yun

2014-01-01

A high performance sample-and-hold (S/H) circuit used in a pipelined analog-to-digital converter (ADC) is presented. Capacitor flip-around architecture is used in this S/H circuit with a novel gain-boosted differential folded cascode operational transconductance amplifier. A double-bootstrapped switch is designed to improve the performance of the circuit. The circuit is implemented using a 0.18 μm 1P6M CMOS process. Measurement results show that the effective number of bits is 14.03 bits, the spurious free dynamic range is 94.62 dB, the signal to noise and distortion ratio is 86.28 dB, and the total harmonic distortion is −91:84 dB for a 5 MHz input signal with 50 MS/s sampling rate. A pipeline ADC with the designed S/H circuit has been implemented. (semiconductor integrated circuits)

SEMICONDUCTOR INTEGRATED CIRCUITS A 10-bit 200-kS/s SAR ADC IP core for a touch screen SoC

Science.gov (United States)

Xingyuan, Tong; Yintang, Yang; Zhangming, Zhu; Wenfang, Sheng

2010-10-01

Based on a 5 MSBs (most-significant-bits)-plus-5 LSBs (least-significant-bits) C-R hybrid D/A conversion and low-offset pseudo-differential comparison approach, with capacitor array axially symmetric layout topology and resistor string low gradient mismatch placement method, an 8-channel 10-bit 200-kS/s SAR ADC (successive-approximation-register analog-to-digital converter) IP core for a touch screen SoC (system-on-chip) is implemented in a 0.18 μm 1P5M CMOS logic process. Design considerations for the touch screen SAR ADC are included. With a 1.8 V power supply, the DNL (differential non-linearity) and INL (integral non-linearity) of this converter are measured to be about 0.32 LSB and 0.81 LSB respectively. With an input frequency of 91 kHz at 200-kS/s sampling rate, the spurious-free dynamic range and effective-number-of-bits are measured to be 63.2 dB and 9.15 bits respectively, and the power is about 136 μW. This converter occupies an area of about 0.08 mm2. The design results show that it is very suitable for touch screen SoC applications.

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.

Nanocrystalline, superhard, ductile ceramic coatings for roller-cone bit bearings

Energy Technology Data Exchange (ETDEWEB)

Namavar, F.; Colter, P.; Karimy, H. [Spire Corp., Bedford, MA (United States)] [and others

1997-12-31

The established method for construction of roller bits utilizes carburized steel, frequently with inserted metal bearing surfaces. This construction provides the necessary surface hardness while maintaining other desirable properties in the core. Protective coatings are a logical development where enhanced hardness, wear resistance, corrosion resistance, and surface properties are required. The wear properties of geothermal roller-cone bit bearings could be further improved by application of protective ceramic hard coatings consisting of nanometer-sized crystallites. Nanocrystalline protective coatings provide the required combination of hardness and toughness which has not been available thus far using traditional ceramics having larger grains. Increased durability of roller-cone bit bearings will ultimately reduce the cost of drilling geothermal wells through increased durability.

Validation of the VitaBit Sit–Stand Tracker: Detecting Sitting, Standing, and Activity Patterns

Directory of Open Access Journals (Sweden)

Nathalie M. Berninger

2018-03-01

Full Text Available Sedentary behavior (SB has detrimental consequences and cannot be compensated for through moderate-to-vigorous physical activity (PA. In order to understand and mitigate SB, tools for measuring and monitoring SB are essential. While current direct-to-customer wearables focus on PA, the VitaBit validated in this study was developed to focus on SB. It was tested in a laboratory and in a free-living condition, comparing it to direct observation and to a current best-practice device, the ActiGraph, on a minute-by-minute basis. In the laboratory, the VitaBit yielded specificity and negative predictive rates (NPR of above 91.2% for sitting and standing, while sensitivity and precision ranged from 74.6% to 85.7%. For walking, all performance values exceeded 97.3%. In the free-living condition, the device revealed performance of over 72.6% for sitting with the ActiGraph as criterion. While sensitivity and precision for standing and walking ranged from 48.2% to 68.7%, specificity and NPR exceeded 83.9%. According to the laboratory findings, high performance for sitting, standing, and walking makes the VitaBit eligible for SB monitoring. As the results are not transferrable to daily life activities, a direct observation study in a free-living setting is recommended.

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.

A Symmetric Chaos-Based Image Cipher with an Improved Bit-Level Permutation Strategy

Directory of Open Access Journals (Sweden)

Chong Fu

2014-02-01

Full Text Available Very recently, several chaos-based image ciphers using a bit-level permutation have been suggested and shown promising results. Due to the diffusion effect introduced in the permutation stage, the workload of the time-consuming diffusion stage is reduced, and hence the performance of the cryptosystem is improved. In this paper, a symmetric chaos-based image cipher with a 3D cat map-based spatial bit-level permutation strategy is proposed. Compared with those recently proposed bit-level permutation methods, the diffusion effect of the new method is superior as the bits are shuffled among different bit-planes rather than within the same bit-plane. Moreover, the diffusion key stream extracted from hyperchaotic system is related to both the secret key and the plain image, which enhances the security against known/chosen plaintext attack. Extensive security analysis has been performed on the proposed scheme, including the most important ones like key space analysis, key sensitivity analysis, plaintext sensitivity analysis and various statistical analyses, which has demonstrated the satisfactory security of the proposed scheme

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.

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

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

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.

Social motivation in prospective memory: higher importance ratings and reported performance rates for social tasks.

Science.gov (United States)

Penningroth, Suzanna L; Scott, Walter D; Freuen, Margaret

2011-03-01

Few studies have addressed social motivation in prospective memory (PM). In a pilot study and two main studies, we examined whether social PM tasks possess a motivational advantage over nonsocial PM tasks. In the pilot study and Study 1, participants listed their real-life important and less important PM tasks. Independent raters categorized the PM tasks as social or nonsocial. Results from both studies showed a higher proportion of tasks rated as social when important tasks were requested than when less important tasks were requested. In Study 1, participants also reported whether they had remembered to perform each PM task. Reported performance rates were higher for tasks rated as social than for those rated as nonsocial. Finally, in Study 2, participants rated the importance of two hypothetical PM tasks, one social and one nonsocial. The social PM task was rated higher in importance. Overall, these findings suggest that social PM tasks are viewed as more important than nonsocial PM tasks and they are more likely to be performed. We propose that consideration of the social relevance of PM will lead to a more complete and ecologically valid theoretical description of PM performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

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

Polling-Based High-Bit-Rate Packet Transfer in a Microcellular Network to Allow Fast Terminals

Science.gov (United States)

Hoa, Phan Thanh; Lambertsen, Gaute; Yamada, Takahiko

A microcellular network will be a good candidate for the future broadband mobile network. It is expected to support high-bit-rate connection for many fast mobile users if the handover is processed fast enough to lessen its impact on QoS requirements. One of the promising techniques is believed to use for the wireless interface in such a microcellular network is the WLAN (Wireless LAN) technique due to its very high wireless channel rate. However, the less capability of mobility support of this technique must be improved to be able to expand its utilization for the microcellular environment. The reason of its less support mobility is large handover latency delay caused by contention-based handover to the new BS (base station) and delay of re-forwarding data from the old to new BS. This paper presents a proposal of multi-polling and dynamic LMC (Logical Macro Cell) to reduce mentioned above delays. Polling frame for an MT (Mobile Terminal) is sent from every BS belonging to the same LMC — a virtual single macro cell that is a multicast group of several adjacent micro-cells in which an MT is communicating. Instead of contending for the medium of a new BS during handover, the MT responds to the polling sent from that new BS to enable the transition. Because only one BS of the LMC receives the polling ACK (acknowledgement) directly from the MT, this ACK frame has to be multicast to all BSs of the same LMC through the terrestrial network to continue sending the next polling cycle at each BS. Moreover, when an MT hands over to a new cell, its current LMC is switched over to a newly corresponding LMC to prevent the future contending for a new LMC. By this way, an MT can do handover between micro-cells of an LMC smoothly because the redundant resource is reserved for it at neighboring cells, no need to contend with others. Our simulation results using the OMNeT++ simulator illustrate the performance achievements of the multi-polling and dynamic LMC scheme in eliminating

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

Energy Technology Data Exchange (ETDEWEB)

Jo, Jong Young; Song, Dong Soo; Byun, Choong Sub [Korea Electric Power Research Institute, Daejeon (Korea, Republic of)

2008-07-01

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{sup 3} and 2400ppm BIT, 3.4m{sup 3} and 0ppm BIT and no volume of BIT. The results show that the deactivation of BIT is plausible for success.

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

Kombinasi Steganografi Berbasis Bit Matching dan Kriptografi DES untuk Pengamanan Data

Directory of Open Access Journals (Sweden)

Budi Prasetiyo

2015-05-01

Full Text Available Pada penelitian ini dilakukan kombinasi steganografi dan kriptografi untuk pengamanan data dengan tidak mengubah kualitas media cover. Metode steganografi yang digunakan dengan melakukan pencocokan bit pesan pada bit MSB citra. Proses pencocokan dilakukan secara divide and conquer. Hasil indeks posisi bit kemudian dienkripsi menggunakan algoritma kriptografi Data Encryption Standard (DES. Masukkan data berupa pesan teks, citra, dan kunci. Output yang dihasilkan berupa chiperteks posisi bit yang dapat digunakan untuk merahasiakan data. Untuk mengetahui isi pesan semula diperlukan kunci dan citra yang sama. Kombinasi yang dihasilkan dapat digunakan untuk pengamanan data. Kelebihan metode tersebut citra tidak mengalami perubahan kualitas dan kapasitas pesan yang disimpan dapat lebih besar dari citra. Hasil pengujian menunjukkan citra hitam putih maupun color dapat digunakan sebagai cover, kecuali citra 100% hitam dan 100% putih. Proses pencocokan pada warna citra yang bervariasi lebih cepat. Kerusakan pesan dengan penambahan noise salt and peper mulai terjadi pada nilai MSE 0,0067 dan gaussian mulai terjadi pada nilai MSE 0,00234. 

Linear transceiver design for nonorthogonal amplify-and-forward protocol using a bit error rate criterion

KAUST Repository

Ahmed, Qasim Zeeshan; Park, Kihong; Alouini, Mohamed-Slim; Aï ssa, Sonia

2014-01-01

The ever growing demand of higher data rates can now be addressed by exploiting cooperative diversity. This form of diversity has become a fundamental technique for achieving spatial diversity by exploiting the presence of idle users in the network

Variable Rate Characteristic Waveform Interpolation Speech Coder Based on Phonetic Classification

Institute of Scientific and Technical Information of China (English)

WANG Jing; KUANG Jing-ming; ZHAO Sheng-hui

2007-01-01

A variable-bit-rate characteristic waveform interpolation (VBR-CWI) speech codec with about 1.8kbit/s average bit rate which integrates phonetic classification into characteristic waveform (CW) decomposition is proposed.Each input frame is classified into one of 4 phonetic classes.Non-speech frames are represented with Bark-band noise model.The extracted CWs become rapidly evolving waveforms (REWs) or slowly evolving waveforms (SEWs) in the cases of unvoiced or stationary voiced frames respectively, while mixed voiced frames use the same CW decomposition as that in the conventional CWI.Experimental results show that the proposed codec can eliminate most buzzy and noisy artifacts existing in the fixed-bit-rate characteristic waveform interpolation (FBR-CWI) speech codec, the average bit rate can be much lower, and its reconstructed speech quality is much better than FS 1016 CELP at 4.8kbit/s and similar to G.723.1 ACELP at 5.3kbit/s.

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.

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

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

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

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....

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...

Rate Adaptive OFDMA Communication Systems

International Nuclear Information System (INIS)

Abdelhakim, M.M.M.

2009-01-01

Due to the varying nature of the wireless channels, adapting the transmission parameters, such as code rate, modulation order and power, in response to the channel variations provides a significant improvement in the system performance. In the OFDM systems, Per-Frame adaptation (PFA) can be employed where the transmission variables are fixed over a given frame and may change from one frame to the other. Subband (tile) loading offers more degrees of adaptation such that each group of carriers (subband) uses the same transmission parameters and different subbands may use different parameters. Changing the code rate for each tile in the same frame, results in transmitting multiple codewords (MCWs) for a single frame. In this thesis a scheme is proposed for adaptively changing the code rate of coded OFDMA systems via changing the puncturing rate within a single codeword (SCW). In the proposed structure, the data is encoded with the lowest available code rate then it is divided among the different tiles where it is punctured adaptively based on some measure of the channel quality for each tile. The proposed scheme is compared against using multiple codewords (MCWs) where the different code rates for the tiles are obtained using separate encoding processes. For bit interleaved coded modulation architecture two novel interleaving methods are proposed, namely the puncturing dependant interleaver (PDI) and interleaved puncturing (IntP), which provide larger interleaving depth. In the PDI method the coded bits with the same rate over different tiles are grouped for interleaving. In IntP structure the interleaving is performed prior to puncturing. The performance of the adaptive puncturing technique is investigated under constant bit rate constraint and variable bit rate. Two different adaptive modulation and coding (AMC) selection methods are examined for variable bit rate adaptive system. The first is a recursive scheme that operates directly on the SNR whereas the second

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

Rich or poor: Who should pay higher tax rates?

Science.gov (United States)

Murilo Castro de Oliveira, Paulo

2017-08-01

A dynamic agent model is introduced with an annual random wealth multiplicative process followed by taxes paid according to a linear wealth-dependent tax rate. If poor agents pay higher tax rates than rich agents, eventually all wealth becomes concentrated in the hands of a single agent. By contrast, if poor agents are subject to lower tax rates, the economic collective process continues forever.

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

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

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)

The Random Telegraph Signal Behavior of Intermittently Stuck Bits in SDRAMs

Science.gov (United States)

Chugg, Andrew Michael; Burnell, Andrew J.; Duncan, Peter H.; Parker, Sarah; Ward, Jonathan J.

2009-12-01

This paper reports behavior analogous to the Random Telegraph Signal (RTS) seen in the leakage currents from radiation induced hot pixels in Charge Coupled Devices (CCDs), but in the context of stuck bits in Synchronous Dynamic Random Access Memories (SDRAMs). Our analysis suggests that pseudo-random sticking and unsticking of the SDRAM bits is due to thermally induced fluctuations in leakage current through displacement damage complexes in depletion regions that were created by high-energy neutron and proton interactions. It is shown that the number of observed stuck bits increases exponentially with temperature, due to the general increase in the leakage currents through the damage centers with temperature. Nevertheless, some stuck bits are seen to pseudo-randomly stick and unstick in the context of a continuously rising trend of temperature, thus demonstrating that their damage centers can exist in multiple widely spaced, discrete levels of leakage current, which is highly consistent with RTS. This implies that these intermittently stuck bits (ISBs) are a displacement damage phenomenon and are unrelated to microdose issues, which is confirmed by the observation that they also occur in unbiased irradiation. Finally, we note that observed variations in the periodicity of the sticking and unsticking behavior on several timescales is most readily explained by multiple leakage current pathways through displacement damage complexes spontaneously and independently opening and closing under the influence of thermal vibrations.

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

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...

Semifragile Speech Watermarking Based on Least Significant Bit Replacement of Line Spectral Frequencies

Directory of Open Access Journals (Sweden)

Mohammad Ali Nematollahi

2017-01-01

Full Text Available There are various techniques for speech watermarking based on modifying the linear prediction coefficients (LPCs; however, the estimated and modified LPCs vary from each other even without attacks. Because line spectral frequency (LSF has less sensitivity to watermarking than LPC, watermark bits are embedded into the maximum number of LSFs by applying the least significant bit replacement (LSBR method. To reduce the differences between estimated and modified LPCs, a checking loop is added to minimize the watermark extraction error. Experimental results show that the proposed semifragile speech watermarking method can provide high imperceptibility and that any manipulation of the watermark signal destroys the watermark bits since manipulation changes it to a random stream of bits.

FY 1998 results of the regional consortium R and D project/the venture promotion type regional consortium R and D (small-/medium-size venture creation type). 2nd year. R and D of the audiovisual coding/decoding technology in the low bit-rate mutltimedia communication system; 1998 nendo tei bit rate multimedia tsushinkei ni okeru gazo onsei fugo fukugoka gijutsu no kenkyu kaihatsu seika hokokusho. 2

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

The paper studied how to solve the problems in TV telephones such as low quality of pictures and less application. As to the development of H.263 codec LSI, an architecture which makes the efficient moving image codec possible even at low action frequency was designed for achieving low electric power consumption, and the LSI was mounted. In relation to the development of G.723.1 codec soft on SH3, encoding motion was conducted with audio data inputted, and it was confirmed that the bit stream obtained was effective. For the verification of motion/system of ASIC, conducted were the design/development of the reference board for mobile information devices and the verification using the board. The one that is correspondent to the low bit-rate for development is 1485 macroblock/second in the required performance in MPEG-4, and it was confirmed that it could be fully achieved even by the designed H.263 core. Concerning the object processing, an object extraction algorithm was devised. An algorithm of the moving picture codec was designed by conversion of discrete wavelets which were reduced in memory use amount. (NEDO)

Visual Perception Based Rate Control Algorithm for HEVC

Science.gov (United States)

Feng, Zeqi; Liu, PengYu; Jia, Kebin

2018-01-01

For HEVC, rate control is an indispensably important video coding technology to alleviate the contradiction between video quality and the limited encoding resources during video communication. However, the rate control benchmark algorithm of HEVC ignores subjective visual perception. For key focus regions, bit allocation of LCU is not ideal and subjective quality is unsatisfied. In this paper, a visual perception based rate control algorithm for HEVC is proposed. First bit allocation weight of LCU level is optimized based on the visual perception of luminance and motion to ameliorate video subjective quality. Then λ and QP are adjusted in combination with the bit allocation weight to improve rate distortion performance. Experimental results show that the proposed algorithm reduces average 0.5% BD-BR and maximum 1.09% BD-BR at no cost in bitrate accuracy compared with HEVC (HM15.0). The proposed algorithm devotes to improving video subjective quality under various video applications.

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.

BitCoin meets Google Trends and Wikipedia: Quantifying the relationship between phenomena of the Internet era

Science.gov (United States)

Kristoufek, Ladislav

2013-12-01

Digital currencies have emerged as a new fascinating phenomenon in the financial markets. Recent events on the most popular of the digital currencies - BitCoin - have risen crucial questions about behavior of its exchange rates and they offer a field to study dynamics of the market which consists practically only of speculative traders with no fundamentalists as there is no fundamental value to the currency. In the paper, we connect two phenomena of the latest years - digital currencies, namely BitCoin, and search queries on Google Trends and Wikipedia - and study their relationship. We show that not only are the search queries and the prices connected but there also exists a pronounced asymmetry between the effect of an increased interest in the currency while being above or below its trend value.

Real-time minimal-bit-error probability decoding of convolutional codes

Science.gov (United States)

Lee, L.-N.

1974-01-01

A recursive procedure is derived for decoding of rate R = 1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit, subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e., fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications, such as in the inner coding system for concatenated coding.

Real-time minimal bit error probability decoding of convolutional codes

Science.gov (United States)

Lee, L. N.

1973-01-01

A recursive procedure is derived for decoding of rate R=1/n binary convolutional codes which minimizes the probability of the individual decoding decisions for each information bit subject to the constraint that the decoding delay be limited to Delta branches. This new decoding algorithm is similar to, but somewhat more complex than, the Viterbi decoding algorithm. A real-time, i.e. fixed decoding delay, version of the Viterbi algorithm is also developed and used for comparison to the new algorithm on simulated channels. It is shown that the new algorithm offers advantages over Viterbi decoding in soft-decision applications such as in the inner coding system for concatenated coding.

Multichannel analyzer with real-time correction of counting losses based on a fast 16/32 bit microprocessor

International Nuclear Information System (INIS)

Westphal, G.P.; Kasa, T.

1984-01-01

It is demonstrated that from a modern microprocessor with 32 bit architecture and from standard VLSI peripheral chips a multichannel analyzer with real-time correction of counting losses may be designed in a very flexible yet cost-effective manner. Throughput rates of 100,000 events/second are a good match even for high-rate spectroscopy systems and may be further enhanced by the use of already available CPU chips with higher clock frequency. Low power consumption and a very compact form factor make the design highly recommendable for portable applications. By means of a simple and easily reproducible rotating sample device the dynamic response of the VPG counting loss correction method have been tested and found to be more than sufficient for conceivable real-time applications. Enhanced statistical accuracy of correction factors may be traded against speed of response by the mere change of one preset value which lends itself to the simple implementation of self-adapting systems. Reliability as well as user convenience is improved by self-calibration of pulse evolution time in the VPG counting loss correction unit

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.

True random bit generators based on current time series of contact glow discharge electrolysis

Science.gov (United States)

Rojas, Andrea Espinel; Allagui, Anis; Elwakil, Ahmed S.; Alawadhi, Hussain

2018-05-01

Random bit generators (RBGs) in today's digital information and communication systems employ a high rate physical entropy sources such as electronic, photonic, or thermal time series signals. However, the proper functioning of such physical systems is bound by specific constrains that make them in some cases weak and susceptible to external attacks. In this study, we show that the electrical current time series of contact glow discharge electrolysis, which is a dc voltage-powered micro-plasma in liquids, can be used for generating random bit sequences in a wide range of high dc voltages. The current signal is quantized into a binary stream by first using a simple moving average function which makes the distribution centered around zero, and then applying logical operations which enables the binarized data to pass all tests in industry-standard randomness test suite by the National Institute of Standard Technology. Furthermore, the robustness of this RBG against power supply attacks has been examined and verified.

Prediction of sonic flow conditions at drill bit nozzles to minimize complications in UBD

Energy Technology Data Exchange (ETDEWEB)

Guo, B.; Ghalambor, A. [Louisiana Univ., Lafayette, LA (United States); Al-Bemani, A.S. [Sultan Qaboos Univ. (Oman)

2002-06-01

Sonic flow at drill bit nozzles can complicate underbalanced drilling (UBD) operations, and should be considered when choosing bit nozzles and fluid injection rates. The complications stem from pressure discontinuity and temperature drop at the nozzle. UBD refers to drilling operations where the drilling fluid pressures in the borehole are maintained at less than the pore pressure in the formation rock in the open-hole section. UBD has become a popular drilling method because it offers minimal lost circulation and reduces formation damage. This paper presents an analytical model for calculating the critical pressure ratio where two-phase sonic flow occurs. In particular, it describes how Sachdeva's two-phase choke model can be used to estimate the critical pressure ratio at nozzles that cause sonic flow. The critical pressure ratio charts can be coded in spreadsheets. The critical pressure ratio depends on the in-situ volumetric gas content, or gas-liquid ratio, which depends on gas injection and pressure. 6 refs., 2 tabs., 5 figs.

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.

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.

Parallel efficient rate control methods for JPEG 2000

Science.gov (United States)

Martínez-del-Amor, Miguel Á.; Bruns, Volker; Sparenberg, Heiko

2017-09-01

Since the introduction of JPEG 2000, several rate control methods have been proposed. Among them, post-compression rate-distortion optimization (PCRD-Opt) is the most widely used, and the one recommended by the standard. The approach followed by this method is to first compress the entire image split in code blocks, and subsequently, optimally truncate the set of generated bit streams according to the maximum target bit rate constraint. The literature proposes various strategies on how to estimate ahead of time where a block will get truncated in order to stop the execution prematurely and save time. However, none of them have been defined bearing in mind a parallel implementation. Today, multi-core and many-core architectures are becoming popular for JPEG 2000 codecs implementations. Therefore, in this paper, we analyze how some techniques for efficient rate control can be deployed in GPUs. In order to do that, the design of our GPU-based codec is extended, allowing stopping the process at a given point. This extension also harnesses a higher level of parallelism on the GPU, leading to up to 40% of speedup with 4K test material on a Titan X. In a second step, three selected rate control methods are adapted and implemented in our parallel encoder. A comparison is then carried out, and used to select the best candidate to be deployed in a GPU encoder, which gave an extra 40% of speedup in those situations where it was really employed.

A 10-bit column-parallel cyclic ADC for high-speed CMOS image sensors

International Nuclear Information System (INIS)

Han Ye; Li Quanliang; Shi Cong; Wu Nanjian

2013-01-01

This paper presents a high-speed column-parallel cyclic analog-to-digital converter (ADC) for a CMOS image sensor. A correlated double sampling (CDS) circuit is integrated in the ADC, which avoids a stand-alone CDS circuit block. An offset cancellation technique is also introduced, which reduces the column fixed-pattern noise (FPN) effectively. One single channel ADC with an area less than 0.02 mm 2 was implemented in a 0.13 μm CMOS image sensor process. The resolution of the proposed ADC is 10-bit, and the conversion rate is 1.6 MS/s. The measured differential nonlinearity and integral nonlinearity are 0.89 LSB and 6.2 LSB together with CDS, respectively. The power consumption from 3.3 V supply is only 0.66 mW. An array of 48 10-bit column-parallel cyclic ADCs was integrated into an array of CMOS image sensor pixels. The measured results indicated that the ADC circuit is suitable for high-speed CMOS image sensors. (semiconductor integrated circuits)

Adjustable Nyquist-rate System for Single-Bit Sigma-Delta ADC with Alternative FIR Architecture

Science.gov (United States)

Frick, Vincent; Dadouche, Foudil; Berviller, Hervé

2016-09-01

This paper presents a new smart and compact system dedicated to control the output sampling frequency of an analogue-to-digital converters (ADC) based on single-bit sigma-delta (ΣΔ) modulator. This system dramatically improves the spectral analysis capabilities of power network analysers (power meters) by adjusting the ADC's sampling frequency to the input signal's fundamental frequency with a few parts per million accuracy. The trade-off between straightforwardness and performance that motivated the choice of the ADC's architecture are preliminary discussed. It particularly comes along with design considerations of an ultra-steep direct-form FIR that is optimised in terms of size and operating speed. Thanks to compact standard VHDL language description, the architecture of the proposed system is particularly suitable for application-specific integrated circuit (ASIC) implementation-oriented low-power and low-cost power meter applications. Field programmable gate array (FPGA) prototyping and experimental results validate the adjustable sampling frequency concept. They also show that the system can perform better in terms of implementation and power capabilities compared to dedicated IP resources.

Architecture and performance of radiation-hardened 64-bit SOS/MNOS memory

International Nuclear Information System (INIS)

Kliment, D.C.; Ronen, R.S.; Nielsen, R.L.; Seymour, R.N.; Splinter, M.R.

1976-01-01

This paper discusses the circuit architecture and performance of a nonvolatile 64-bit MNOS memory fabricated on silicon on sapphire (SOS). The circuit is a test vehicle designed to demonstrate the feasibility of a high-performance, high-density, radiation-hardened MNOS/SOS memory. The array is organized as 16 words by 4 bits and is fully decoded. It utilizes a two-(MNOS) transistor-per-bit cell and differential sensing scheme and is realized in PMOS static resistor load logic. The circuit was fabricated and tested as both a fast write random access memory (RAM) and an electrically alterable read only memory (EAROM) to demonstrate design and process flexibility. Discrete device parameters such as retention, circuit electrical characteristics, and tolerance to total dose and transient radiation are presented

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

A Novel Digital Background Calibration Technique for 16 bit SHA-less Multibit Pipelined ADC

Directory of Open Access Journals (Sweden)

Swina Narula

2016-01-01

Full Text Available In this paper, a high resolution of 16 bit and high speed of 125MS/s, multibit Pipelined ADC with digital background calibration is presented. In order to achieve low power, SHA-less front end is used with multibit stages. The first and second stages are used here as a 3.5 bit and the stages from third to seventh are of 2.5 bit and last stage is of 3-bit flash ADC. After bit alignment and truncation of total 19 bits, 16 bits are used as final digital output. To precise the remove linear gain error of the residue amplifier and capacitor mismatching error, a digital background calibration technique is used, which is a combination of signal dependent dithering (SDD and butterfly shuffler. To improve settling time of residue amplifier, a special circuit of voltage separation is used. With the proposed digital background calibration technique, the spurious-free dynamic range (SFDR has been improved to 97.74 dB @30 MHz and 88.9 dB @150 MHz, and the signal-to-noise and distortion ratio (SNDR has been improved to 79.77 dB @ 30 MHz, and 73.5 dB @ 150 MHz. The implementation of the Pipelined ADC has been completed with technology parameters of 0.18μm CMOS process with 1.8 V supply. Total power consumption is 300 mW by the proposed ADC.

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 ...

ColliderBit. A GAMBIT module for the calculation of high-energy collider observables and likelihoods

Energy Technology Data Exchange (ETDEWEB)

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); Buckley, Andy [University of Glasgow, SUPA, School of Physics and Astronomy, Glasgow (United Kingdom); Dal, Lars A.; Krislock, Abram; Raklev, Are [University of Oslo, Department of Physics, Oslo (Norway); Farmer, Ben [AlbaNova University Centre, Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Jackson, Paul; Murnane, Daniel; 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); Kvellestad, Anders [NORDITA, Stockholm (Sweden); Putze, Antje [Universite de Savoie, LAPTh, Annecy-le-Vieux (France); Rogan, Christopher [Harvard University, Department of Physics, Cambridge, MA (United States); Saavedra, Aldo [Australian Research Council Centre of Excellence for Particle Physics at the Tera-scale (Australia); The University of Sydney, Faculty of Engineering and Information Technologies, Centre for Translational Data Science, School of Physics, Sydney, NSW (Australia); Scott, Pat [Imperial College London, Blackett Laboratory, Department of Physics, London (United Kingdom); Weniger, Christoph [University of Amsterdam, GRAPPA, Institute of Physics, Amsterdam (Netherlands); Collaboration: The GAMBIT Scanner Workgroup

2017-11-15

We describe ColliderBit, a new code for the calculation of high energy collider observables in theories of physics beyond the Standard Model (BSM). ColliderBit features a generic interface to BSM models, a unique parallelised Monte Carlo event generation scheme suitable for large-scale supercomputer applications, and a number of LHC analyses, covering a reasonable range of the BSM signatures currently sought by ATLAS and CMS. ColliderBit also calculates likelihoods for Higgs sector observables, and LEP searches for BSM particles. These features are provided by a combination of new code unique toColliderBit, and interfaces to existing state-of-the-art public codes. ColliderBit is both an important part of the GAMBIT framework for BSM inference, and a standalone tool for efficiently applying collider constraints to theories of new physics. (orig.)

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...

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.

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.

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.

Differential Fault Analysis on CLEFIA with 128, 192, and 256-Bit Keys

Science.gov (United States)

Takahashi, Junko; Fukunaga, Toshinori

This paper describes a differential fault analysis (DFA) attack against CLEFIA. The proposed attack can be applied to CLEFIA with all supported keys: 128, 192, and 256-bit keys. DFA is a type of side-channel attack. This attack enables the recovery of secret keys by injecting faults into a secure device during its computation of the cryptographic algorithm and comparing the correct ciphertext with the faulty one. CLEFIA is a 128-bit blockcipher with 128, 192, and 256-bit keys developed by the Sony Corporation in 2007. CLEFIA employs a generalized Feistel structure with four data lines. We developed a new attack method that uses this characteristic structure of the CLEFIA algorithm. On the basis of the proposed attack, only 2 pairs of correct and faulty ciphertexts are needed to retrieve the 128-bit key, and 10.78 pairs on average are needed to retrieve the 192 and 256-bit keys. The proposed attack is more efficient than any previously reported. In order to verify the proposed attack and estimate the calculation time to recover the secret key, we conducted an attack simulation using a PC. The simulation results show that we can obtain each secret key within three minutes on average. This result shows that we can obtain the entire key within a feasible computational time.

Single-chip pulse programmer for magnetic resonance imaging using a 32-bit microcontroller.

Science.gov (United States)

Handa, Shinya; Domalain, Thierry; Kose, Katsumi

2007-08-01

A magnetic resonance imaging (MRI) pulse programmer has been developed using a single-chip microcontroller (ADmicroC7026). The microcontroller includes all the components required for the MRI pulse programmer: a 32-bit RISC CPU core, 62 kbytes of flash memory, 8 kbytes of SRAM, two 32-bit timers, four 12-bit DA converters, and 40 bits of general purpose I/O. An evaluation board for the microcontroller was connected to a host personal computer (PC), an MRI transceiver, and a gradient driver using interface circuitry. Target (embedded) and host PC programs were developed to enable MRI pulse sequence generation by the microcontroller. The pulse programmer achieved a (nominal) time resolution of approximately 100 ns and a minimum time delay between successive events of approximately 9 micros. Imaging experiments using the pulse programmer demonstrated the effectiveness of our approach.

Using game theory for perceptual tuned rate control algorithm in video coding

Science.gov (United States)

Luo, Jiancong; Ahmad, Ishfaq

2005-03-01

This paper proposes a game theoretical rate control technique for video compression. Using a cooperative gaming approach, which has been utilized in several branches of natural and social sciences because of its enormous potential for solving constrained optimization problems, we propose a dual-level scheme to optimize the perceptual quality while guaranteeing "fairness" in bit allocation among macroblocks. At the frame level, the algorithm allocates target bits to frames based on their coding complexity. At the macroblock level, the algorithm distributes bits to macroblocks by defining a bargaining game. Macroblocks play cooperatively to compete for shares of resources (bits) to optimize their quantization scales while considering the Human Visual System"s perceptual property. Since the whole frame is an entity perceived by viewers, macroblocks compete cooperatively under a global objective of achieving the best quality with the given bit constraint. The major advantage of the proposed approach is that the cooperative game leads to an optimal and fair bit allocation strategy based on the Nash Bargaining Solution. Another advantage is that it allows multi-objective optimization with multiple decision makers (macroblocks). The simulation results testify the algorithm"s ability to achieve accurate bit rate with good perceptual quality, and to maintain a stable buffer level.

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.

Power and area efficient 4-bit column-level ADC in a CMOS pixel sensor for the ILD vertex detector

International Nuclear Information System (INIS)

Zhang, L; Morel, F; Hu-Guo, Ch; Hu, Y

2013-01-01

A 48 × 64 pixels prototype CMOS pixel sensor (CPS) integrated with 4-bit column-level, self triggered ADCs for the outer layers of the ILD vertex detector (VTX) was developed and fabricated in a 0.35 μm CMOS process with a pixel pitch of 35 μm. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation. The ADCs accommodating the pixel read out in a rolling shutter mode complete the conversion by performing a multi-bit/step approximation. The design was optimised for power saving at sampling frequency. The prototype sensor is currently at the stage of being started testing and evaluation. So what is described is based on post simulation results rather than test data. This 4-bit ADC dissipates, at a 3-V supply and 6.25-MS/s sampling rate, 486 μW in its inactive mode, which is by far the most frequent. This value rises to 714 μW in case of the active mode. Its footprint amounts to 35 × 545 μm 2 .

Single-word multiple-bit upsets in static random access devices

International Nuclear Information System (INIS)

Koga, R.; Pinkerton, S.D.; Lie, T.J.; Crawford, K.B.

1993-01-01

Energetic ions and protons can cause single event upsets (SEUs) in static random access memory (SRAM) cells. In some cases multiple bits may be upset as the result of a single event. Space-borne electronics systems incorporating high-density SRAM are vulnerable to single-word multiple-bit upsets (SMUs). The authors review here recent observations of SMU, present the results of a systematic investigation of the physical cell arrangements employed in several currently available SRAM device types, and discuss implications for the occurrence and mitigation of SMU

Design and development of CAMAC 12 bit ADC/DAC dual purpose module

International Nuclear Information System (INIS)

Kulkarni, S.G.; Gore, J.A.; Ramlal, V.; Matkar, U.V.; Lokare, R.N.; Yadav, M.L.; Ekambaram, M.; Gupta, A.K.; Datar, V.M.

2013-01-01

A dual function CAMAC module is designed for Pelletron Accelerator which can function as 12 bit 8 channels DAC or 12 bit 16 channels ADC. Spartan 2 series of FPGA is used for implementing the CAMAC interface logic as well as logic for ADC/DAC interface. The PCB has both the ADC and DAC mounted but the module can have only one function selected due to wiring constraint. Two different VHDL programs (one for the ADC and other for the DAC) reside on the EEPROM permitting selection of any one as per the functionality required. The module is working as a 12 bit DAC at BARC-TIFR Pelletron Linac Facility, successfully. (author)

A 10-bit 50-MS/s subsampling pipelined ADC based on SMDAC and opamp sharing

Energy Technology Data Exchange (ETDEWEB)

Chen Lijie; Zhou Yumei; Wei Baoyue, E-mail: frankdhz@yahoo.com.cn [Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029 (China)

2010-11-15

This paper describes a 10-bit, 50-MS/s pipelined A/D converter (ADC) with proposed area- and power-efficient architecture. The conventional dedicated sample-hold-amplifier (SHA) is eliminated and the matching requirement between the first multiplying digital-to-analog converter (MDAC) and sub-ADC is also avoided by using the SHA merged with the first MDAC (SMDAC) architecture, which features low power and stabilization. Further reduction of power and area is achieved by sharing an opamp between two successive pipelined stages, in which the effect of opamp offset and crosstalk between stages is decreased. So the 10-bit pipelined ADC is realized using just four opamps. The ADC demonstrates a maximum signal-to-noise distortion ratio and spurious free dynamic range of 52.67 dB and 59.44 dB, respectively, with a Nyquist input at full sampling rate. Constant dynamic performance for input frequencies up to 49.7 MHz, which is the twofold Nyquist rate, is achieved at 50 MS/s. The ADC prototype only occupies an active area of 1.81 mm{sup 2} in a 0.35 {mu}m CMOS process, and consumes 133 mW when sampling at 50 MHz from a 3.3-V power supply.

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...

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...

ParBiBit: Parallel tool for binary biclustering on modern distributed-memory systems.

Science.gov (United States)

González-Domínguez, Jorge; Expósito, Roberto R

2018-01-01

Biclustering techniques are gaining attention in the analysis of large-scale datasets as they identify two-dimensional submatrices where both rows and columns are correlated. In this work we present ParBiBit, a parallel tool to accelerate the search of interesting biclusters on binary datasets, which are very popular on different fields such as genetics, marketing or text mining. It is based on the state-of-the-art sequential Java tool BiBit, which has been proved accurate by several studies, especially on scenarios that result on many large biclusters. ParBiBit uses the same methodology as BiBit (grouping the binary information into patterns) and provides the same results. Nevertheless, our tool significantly improves performance thanks to an efficient implementation based on C++11 that includes support for threads and MPI processes in order to exploit the compute capabilities of modern distributed-memory systems, which provide several multicore CPU nodes interconnected through a network. Our performance evaluation with 18 representative input datasets on two different eight-node systems shows that our tool is significantly faster than the original BiBit. Source code in C++ and MPI running on Linux systems as well as a reference manual are available at https://sourceforge.net/projects/parbibit/.

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 ...

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.

Image Watermarking Scheme for Specifying False Positive Probability and Bit-pattern Embedding

Science.gov (United States)

Sayama, Kohei; Nakamoto, Masayoshi; Muneyasu, Mitsuji; Ohno, Shuichi

This paper treats a discrete wavelet transform(DWT)-based image watermarking with considering the false positive probability and bit-pattern embedding. We propose an iterative embedding algorithm of watermarking signals which are K sets pseudo-random numbers generated by a secret key. In the detection, K correlations between the watermarked DWT coefficients and watermark signals are computed by using the secret key. L correlations are made available for the judgment of the watermark presence with specified false positive probability, and the other K-L correlations are corresponding to the bit-pattern signal. In the experiment, we show the detection results with specified false positive probability and the bit-pattern recovery, and the comparison of the proposed method against JPEG compression, scaling down and cropping.

Rate-cost tradeoffs in control

KAUST Repository

Kostina, Victoria; Hassibi, Babak

2017-01-01

function is the mean-square deviation of the system state from the desired state. We study the fundamental tradeoff between the communication rate r bits/sec and the limsup of the expected cost b, and show a lower bound on the rate necessary to attain b

Achievable Information Rates for Coded Modulation With Hard Decision Decoding for Coherent Fiber-Optic Systems

Science.gov (United States)

Sheikh, Alireza; Amat, Alexandre Graell i.; Liva, Gianluigi

2017-12-01

We analyze the achievable information rates (AIRs) for coded modulation schemes with QAM constellations with both bit-wise and symbol-wise decoders, corresponding to the case where a binary code is used in combination with a higher-order modulation using the bit-interleaved coded modulation (BICM) paradigm and to the case where a nonbinary code over a field matched to the constellation size is used, respectively. In particular, we consider hard decision decoding, which is the preferable option for fiber-optic communication systems where decoding complexity is a concern. Recently, Liga \\emph{et al.} analyzed the AIRs for bit-wise and symbol-wise decoders considering what the authors called \\emph{hard decision decoder} which, however, exploits \\emph{soft information} of the transition probabilities of discrete-input discrete-output channel resulting from the hard detection. As such, the complexity of the decoder is essentially the same as the complexity of a soft decision decoder. In this paper, we analyze instead the AIRs for the standard hard decision decoder, commonly used in practice, where the decoding is based on the Hamming distance metric. We show that if standard hard decision decoding is used, bit-wise decoders yield significantly higher AIRs than symbol-wise decoders. As a result, contrary to the conclusion by Liga \\emph{et al.}, binary decoders together with the BICM paradigm are preferable for spectrally-efficient fiber-optic systems. We also design binary and nonbinary staircase codes and show that, in agreement with the AIRs, binary codes yield better performance.

"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.

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.

FlavBit. A GAMBIT module for computing flavour observables and likelihoods

Energy Technology Data Exchange (ETDEWEB)

Bernlochner, Florian U. [Physikalisches Institut der Rheinischen Friedrich-Wilhelms-Universitaet Bonn (Germany); Chrzaszcz, Marcin [Universitaet Zuerich, Physik-Institut, Zurich (Switzerland); Polish Academy of Sciences, H. Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Dal, Lars A. [University of Oslo, Department of Physics, Oslo (Norway); Farmer, Ben [Oskar Klein Centre for Cosmoparticle Physics, AlbaNova University Centre, Stockholm (Sweden); Stockholm University, Department of Physics, Stockholm (Sweden); Jackson, Paul; White, Martin [University of Adelaide, Department of Physics, Adelaide, SA (Australia); Australian Research Council Centre of Excellence for Particle Physics at the Tera-scale (Australia); Kvellestad, Anders [NORDITA, Stockholm (Sweden); Mahmoudi, Farvah [Univ Lyon, Univ Lyon 1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR5574, Saint-Genis-Laval (France); CERN, Theoretical Physics Department, Geneva (Switzerland); Putze, Antje [LAPTh, Universite de Savoie, CNRS, Annecy-le-Vieux (France); Rogan, Christopher [Harvard University, Department of Physics, Cambridge, MA (United States); Scott, Pat [Imperial College London, Department of Physics, Blackett Laboratory, London (United Kingdom); Serra, Nicola [Universitaet Zuerich, Physik-Institut, Zurich (Switzerland); Weniger, Christoph [University of Amsterdam, GRAPPA, Institute of Physics, Amsterdam (Netherlands); Collaboration: The GAMBIT Flavour Workgroup

2017-11-15

Flavour physics observables are excellent probes of new physics up to very high energy scales. Here we present FlavBit, the dedicated flavour physics module of the global-fitting package GAMBIT. FlavBit includes custom implementations of various likelihood routines for a wide range of flavour observables, including detailed uncertainties and correlations associated with LHCb measurements of rare, leptonic and semileptonic decays of B and D mesons, kaons and pions. It provides a generalised interface to external theory codes such as SuperIso, allowing users to calculate flavour observables in and beyond the Standard Model, and then test them in detail against all relevant experimental data. We describe FlavBit and its constituent physics in some detail, then give examples from supersymmetry and effective field theory illustrating how it can be used both as a standalone library for flavour physics, and within GAMBIT. (orig.)

Two-bit trinary full adder design based on restricted signed-digit numbers

Science.gov (United States)

Ahmed, J. U.; Awwal, A. A. S.; Karim, M. A.

1994-08-01

A 2-bit trinary full adder using a restricted set of a modified signed-digit trinary numeric system is designed. When cascaded together to design a multi-bit adder machine, the resulting system is able to operate at a speed independent of the size of the operands. An optical non-holographic content addressable memory based on binary coded arithmetic is considered for implementing the proposed adder.

Gigahertz repetition rate, sub-femtosecond timing jitter optical pulse train directly generated from a mode-locked Yb:KYW laser.

Science.gov (United States)

Yang, Heewon; Kim, Hyoji; Shin, Junho; Kim, Chur; Choi, Sun Young; Kim, Guang-Hoon; Rotermund, Fabian; Kim, Jungwon

2014-01-01

We show that a 1.13 GHz repetition rate optical pulse train with 0.70 fs high-frequency timing jitter (integration bandwidth of 17.5 kHz-10 MHz, where the measurement instrument-limited noise floor contributes 0.41 fs in 10 MHz bandwidth) can be directly generated from a free-running, single-mode diode-pumped Yb:KYW laser mode-locked by single-wall carbon nanotube-coated mirrors. To our knowledge, this is the lowest-timing-jitter optical pulse train with gigahertz repetition rate ever measured. If this pulse train is used for direct sampling of 565 MHz signals (Nyquist frequency of the pulse train), the jitter level demonstrated would correspond to the projected effective-number-of-bit of 17.8, which is much higher than the thermal noise limit of 50 Ω load resistance (~14 bits).

A Modified Differential Coherent Bit Synchronization Algorithm for BeiDou Weak Signals with Large Frequency Deviation.

Science.gov (United States)

Han, Zhifeng; Liu, Jianye; Li, Rongbing; Zeng, Qinghua; Wang, Yi

2017-07-04

BeiDou system navigation messages are modulated with a secondary NH (Neumann-Hoffman) code of 1 kbps, where frequent bit transitions limit the coherent integration time to 1 millisecond. Therefore, a bit synchronization algorithm is necessary to obtain bit edges and NH code phases. In order to realize bit synchronization for BeiDou weak signals with large frequency deviation, a bit synchronization algorithm based on differential coherent and maximum likelihood is proposed. Firstly, a differential coherent approach is used to remove the effect of frequency deviation, and the differential delay time is set to be a multiple of bit cycle to remove the influence of NH code. Secondly, the maximum likelihood function detection is used to improve the detection probability of weak signals. Finally, Monte Carlo simulations are conducted to analyze the detection performance of the proposed algorithm compared with a traditional algorithm under the CN0s of 20~40 dB-Hz and different frequency deviations. The results show that the proposed algorithm outperforms the traditional method with a frequency deviation of 50 Hz. This algorithm can remove the effect of BeiDou NH code effectively and weaken the influence of frequency deviation. To confirm the feasibility of the proposed algorithm, real data tests are conducted. The proposed algorithm is suitable for BeiDou weak signal bit synchronization with large frequency deviation.

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

An Information-Theoretic Perspective on the Quantum Bit Commitment Impossibility Theorem

Directory of Open Access Journals (Sweden)

Marius Nagy

2018-03-01

Full Text Available This paper proposes a different approach to pinpoint the causes for which an unconditionally secure quantum bit commitment protocol cannot be realized, beyond the technical details on which the proof of Mayers’ no-go theorem is constructed. We have adopted the tools of quantum entropy analysis to investigate the conditions under which the security properties of quantum bit commitment can be circumvented. Our study has revealed that cheating the binding property requires the quantum system acting as the safe to harbor the same amount of uncertainty with respect to both observers (Alice and Bob as well as the use of entanglement. Our analysis also suggests that the ability to cheat one of the two fundamental properties of bit commitment by any of the two participants depends on how much information is leaked from one side of the system to the other and how much remains hidden from the other participant.

Implementation of a two-state quantum bit commitment protocol in optical fibers

International Nuclear Information System (INIS)

Almeida, Á J; Stojanovic, A D; Paunković, N; Loura, R; Mateus, P; Muga, N J; Silva, N A; André, P S; Pinto, A N

2016-01-01

We demonstrate experimentally the feasibility of a two-state quantum bit commitment protocol, which is both concealing and partially binding, assuming technological limitations. The security of this protocol is based on the lack of long-term stable quantum memories. We use a polarization-encoding scheme and optical fiber as a quantum channel. The measurement probability for the commitment is obtained and the optimal cheating strategy demonstrated. The average success rates for an honest player in the case where the measurements are performed using equal bases are 93.4%, when the rectilinear basis is measured, and 96.7%, when the diagonal basis is measured. The rates for the case when the measurements are performed in different bases are 52.9%, when the rectilinear basis is measured, and 55.4% when the diagonal basis is measured. The average success rates for the optimal cheating strategy are 80% and 73.8%, which are way below the success rates of an honest player. Using a strict numerical validity criterion, we show that, for these experimental values, the protocol is secure. (paper)

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

Along-strike structural variation and thermokinematic development of the Cenozoic Bitlis-Zagros fold-thrust belt, Turkey and Iraqi Kurdistan

Science.gov (United States)

Barber, Douglas E.; Stockli, Daniel F.; Koshnaw, Renas I.; Tamar-Agha, Mazin Y.; Yilmaz, Ismail O.

2016-04-01

The Bitlis-Zagros orogen in northern Iraq is a principal element of the Arabia-Eurasia continent collision and is characterized by the lateral intersection of two structural domains: the NW-SE trending Zagros proper system of Iran and the E-W trending Bitlis fold-thrust belt of Turkey and Syria. While these components in northern Iraq share a similar stratigraphic framework, they exhibit along-strike variations in the width and style of tectonic zones, fold morphology and trends, and structural inheritance. However, the distinctions of the Bitlis and Zagros segments remains poorly understood in terms of timing and deformation kinematics as well as first-order controls on fold-thrust development. Structural and stratigraphic study and seismic data combined with low-T thermochronometry provide the basis for reconstructions of the Bitlis-Zagros fold-thrust belt in southeastern Turkey and northern Iraq to elucidate the kinematic and temporal relationship of these two systems. Balanced cross-sections were constructed and incrementally restored to quantify the deformational evolution and use as input for thermokinematic models (FETKIN) to generate thermochronometric ages along the topographic surface of each cross-section line. The forward modeled thermochronometric ages from were then compared to new and previously published apatite and zircon (U-Th)/He and fission-track ages from southeastern Turkey and northern Iraq to test the validity of the timing, rate, and fault-motion geometry associated with each reconstruction. The results of these balanced theromokinematic restorations integrated with constraints from syn-tectonic sedimentation suggest that the Zagros belt between Erbil and Suleimaniyah was affected by an initial phase of Late Cretaceous exhumation related to the Proto-Zagros collision. During the main Zagros phase, deformation advanced rapidly and in-sequence from the Main Zagros Fault to the thin-skinned frontal thrusts (Kirkuk, Shakal, Qamar) from middle

Bit Bang 4: Future of internet - Societal, business, governance and technological aspects

OpenAIRE

Neuvo, Yrjö (ed.); Karvonen, Elina (ed.)

2012-01-01

Bit Bang – Future of the Internet: Societal, business, governance and technological aspects was the fourth multidisciplinary post-graduate course for doctoral students at Aalto University. Altogether 24 students were selected from five Aalto University Schools: School of Arts, Design and Architecture; School of Economics; School of Electrical Engineering; School of Engineering; and School of Science. Bit Bang is part of the MIDE (Multidisciplinary Institute of Digitalisation and Energy) resea...

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.

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...

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)

A 9-Bit 50 MSPS Quadrature Parallel Pipeline ADC for Communication Receiver Application

Science.gov (United States)

Roy, Sounak; Banerjee, Swapna

2018-03-01

This paper presents the design and implementation of a pipeline Analog-to-Digital Converter (ADC) for superheterodyne receiver application. Several enhancement techniques have been applied in implementing the ADC, in order to relax the target specifications of its building blocks. The concepts of time interleaving and double sampling have been used simultaneously to enhance the sampling speed and to reduce the number of amplifiers used in the ADC. Removal of a front end sample-and-hold amplifier is possible by employing dynamic comparators with switched capacitor based comparison of input signal and reference voltage. Each module of the ADC comprises two 2.5-bit stages followed by two 1.5-bit stages and a 3-bit flash stage. Four such pipeline ADC modules are time interleaved using two pairs of non-overlapping clock signals. These two pairs of clock signals are in phase quadrature with each other. Hence the term quadrature parallel pipeline ADC has been used. These configurations ensure that the entire ADC contains only eight operational-trans-conductance amplifiers. The ADC is implemented in a 0.18-μm CMOS process and supply voltage of 1.8 V. The proto-type is tested at sampling frequencies of 50 and 75 MSPS producing an Effective Number of Bits (ENOB) of 6.86- and 6.11-bits respectively. At peak sampling speed, the core ADC consumes only 65 mW of power.

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)

"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...

A Methodology and Tool for Investigation of Artifacts Left by the BitTorrent Client

Directory of Open Access Journals (Sweden)

Algimantas Venčkauskas

2016-05-01

Full Text Available The BitTorrent client application is a popular utility for sharing large files over the Internet. Sometimes, this powerful utility is used to commit cybercrimes, like sharing of illegal material or illegal sharing of legal material. In order to help forensics investigators to fight against these cybercrimes, we carried out an investigation of the artifacts left by the BitTorrent client. We proposed a methodology to locate the artifacts that indicate the BitTorrent client activity performed. Additionally, we designed and implemented a tool that searches for the evidence left by the BitTorrent client application in a local computer running Windows. The tool looks for the four files holding the evidence. The files are as follows: *.torrent, dht.dat, resume.dat, and settings.dat. The tool decodes the files, extracts important information for the forensic investigator and converts it into XML format. The results are combined into a single result file.

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

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...

Area-efficient readout with 14-bit SAR-ADC for CMOS image sensors

Directory of Open Access Journals (Sweden)

Aziza Sassi Ben

2016-01-01

Full Text Available This paper proposes a readout design for CMOS image sensors. It has been squeezed into a 7.5um pitch under a 0.28um 1P3M technology. The ADC performs one 14-bit conversion in only 1.5us and targets a theoretical DNL feature about +1.3/-1 at 14-bit accuracy. Correlated Double Sampling (CDS is performed both in the analog and digital domains to preserve the image quality.

Joint Machine Learning and Game Theory for Rate Control in High Efficiency Video Coding.

Science.gov (United States)

Gao, Wei; Kwong, Sam; Jia, Yuheng

2017-08-25

In this paper, a joint machine learning and game theory modeling (MLGT) framework is proposed for inter frame coding tree unit (CTU) level bit allocation and rate control (RC) optimization in High Efficiency Video Coding (HEVC). First, a support vector machine (SVM) based multi-classification scheme is proposed to improve the prediction accuracy of CTU-level Rate-Distortion (R-D) model. The legacy "chicken-and-egg" dilemma in video coding is proposed to be overcome by the learning-based R-D model. Second, a mixed R-D model based cooperative bargaining game theory is proposed for bit allocation optimization, where the convexity of the mixed R-D model based utility function is proved, and Nash bargaining solution (NBS) is achieved by the proposed iterative solution search method. The minimum utility is adjusted by the reference coding distortion and frame-level Quantization parameter (QP) change. Lastly, intra frame QP and inter frame adaptive bit ratios are adjusted to make inter frames have more bit resources to maintain smooth quality and bit consumption in the bargaining game optimization. Experimental results demonstrate that the proposed MLGT based RC method can achieve much better R-D performances, quality smoothness, bit rate accuracy, buffer control results and subjective visual quality than the other state-of-the-art one-pass RC methods, and the achieved R-D performances are very close to the performance limits from the FixedQP method.

A low power 8-bit successive approximation register A/D for a wireless body sensor node

Energy Technology Data Exchange (ETDEWEB)

Liu Liyuan; Zhang Chun; Wei Shaojun; Wang Zhihua [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China); Li Dongmei; Chen Liangdong, E-mail: lidmei@tsinghua.edu.c [Department of Electronic Engineering, Tsinghua University, Beijing 100084 (China)

2010-06-15

A power efficient 8-bit successive approximation register (SAR) A/D for the vital sign monitoring of a wireless body sensor network (WBSN) is presented. A charge redistribution architecture is employed. The prototype A/D is fabricated in 0.18 {mu}m CMOS. The A/D achieves 7.5 ENOB with sampling rate varying from 64 kHz to 1.5 MHz. The power consumption varies from 10.8 to 225.7 {mu}W. (semiconductor integrated circuits)

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

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

Very Low-Cost 80-Bit Chipless-RFID Tags Inkjet Printed on Ordinary Paper

Directory of Open Access Journals (Sweden)

Cristian Herrojo

2018-05-01

Full Text Available This paper presents a time-domain, chipless-RFID system with 80-bit tags inkjet-printed on ordinary DIN A4 paper. The tags, consisting of a linear chain of resonant elements (with as many resonators as the number of identification bits plus header bits, are read sequentially and by proximity (through near-field coupling. To this end, a transmission line, fed by a harmonic (interrogation signal tuned to the resonance frequency of the tag resonators (or close to it, is used as a reader. Thus, during reader operation, the tag chain is mechanically shifted over the transmission line so that the coupling between the line and the functional resonant elements of the tag chain is favored. Logic states that ‘1’ and ‘0’ are determined by the functionality and non-functionality (resonator detuning, respectively, of the resonant elements of the chain. Through near-field coupling, the transmission coefficient of the line is modulated and, as a result, the output signal is modulated in amplitude (AM, which is the identification code contained in the envelope function. As long as the tags are inkjet-printed on ordinary DIN A4 paper, the cost is minimal. Moreover, such tags can be easily programmed and erased, so that identical tags can be fabricated on a large scale (and programmed at a later stage, further reducing the cost of manufacture. The reported prototype tags, with 80 bits of information plus four header bits, demonstrate the potential of this approach, which is of particular interest to secure paper applications.

Euclidean Geometry Codes, minimum weight words and decodable error-patterns using bit-flipping

DEFF Research Database (Denmark)

Høholdt, Tom; Justesen, Jørn; Jonsson, Bergtor

2005-01-01

We determine the number of minimum wigth words in a class of Euclidean Geometry codes and link the performance of the bit-flipping decoding algorithm to the geometry of the error patterns.......We determine the number of minimum wigth words in a class of Euclidean Geometry codes and link the performance of the bit-flipping decoding algorithm to the geometry of the error patterns....

Interpretation of chest radiographs with a high-resolution (2,000 x 2,000 x 12 bit) display

International Nuclear Information System (INIS)

Cox, G.G.

1989-01-01

This paper presents an evaluation of high-resolution (2K x 2Kx 12 bit) display for interpretation of chest radiographs. Three radiologists chose a total of 165 chest radiographs to ensure representation of nine signs: apical pleural scarring, chronic obstructive pulmonary disease, interstitial processes, atelectasis, pneumothorax, hilar mass, pleural effusion, pneumonia, and nodules. Each chest film was digitized to 4Kx 4Kx 12 bit and averaged to 2Kx 2Kx 12 bit and printed on a laser film printer. The 2K x 2K x 12-bit images were displayed and interactively windowed on a 2K x 2K x 12-bit high-resolution gray-scale cathode ray tube display. Six radiologists, none of whom participated in the case selection process, then interpreted a mixture of the screen film chest radiographs, the laser printed 2K chest radiographs, and the high resolution displayed 2K images

Head and bit patterned media optimization at areal densities of 2.5 Tbit/in2 and beyond

International Nuclear Information System (INIS)

Bashir, M.A.; Schrefl, T.; Dean, J.; Goncharov, A.; Hrkac, G.; Allwood, D.A.; Suess, D.

2012-01-01

Global optimization of writing head is performed using micromagnetics and surrogate optimization. The shape of the pole tip is optimized for bit patterned, exchange spring recording media. The media characteristics define the effective write field and the threshold values for the head field that acts at islands in the adjacent track. Once the required head field characteristics are defined, the pole tip geometry is optimized in order to achieve a high gradient of the effective write field while keeping the write field at the adjacent track below a given value. We computed the write error rate and the adjacent track erasure for different maximum anisotropy in the multilayer, graded media. The results show a linear trade off between the error rate and the number of passes before erasure. For optimal head media combinations we found a bit error rate of 10 -6 with 10 8 pass lines before erasure at 2.5 Tbit/in 2 . - Research Highlights: → Global optimization of writing head is performed using micromagnetics and surrogate optimization. → A method is provided to optimize the pole tip shape while maintaining the head field that acts in the adjacent tracks. → Patterned media structures providing an area density of 2.5 Tbit/in 2 are discussed as a case study. → Media reliability is studied, while taking into account, the magnetostatic field interactions from neighbouring islands and adjacent track erasure under the influence of head field.

A novel image encryption algorithm based on synchronized random bit generated in cascade-coupled chaotic semiconductor ring lasers

Science.gov (United States)

Li, Jiafu; Xiang, Shuiying; Wang, Haoning; Gong, Junkai; Wen, Aijun

2018-03-01

In this paper, a novel image encryption algorithm based on synchronization of physical random bit generated in a cascade-coupled semiconductor ring lasers (CCSRL) system is proposed, and the security analysis is performed. In both transmitter and receiver parts, the CCSRL system is a master-slave configuration consisting of a master semiconductor ring laser (M-SRL) with cross-feedback and a solitary SRL (S-SRL). The proposed image encryption algorithm includes image preprocessing based on conventional chaotic maps, pixel confusion based on control matrix extracted from physical random bit, and pixel diffusion based on random bit stream extracted from physical random bit. Firstly, the preprocessing method is used to eliminate the correlation between adjacent pixels. Secondly, physical random bit with verified randomness is generated based on chaos in the CCSRL system, and is used to simultaneously generate the control matrix and random bit stream. Finally, the control matrix and random bit stream are used for the encryption algorithm in order to change the position and the values of pixels, respectively. Simulation results and security analysis demonstrate that the proposed algorithm is effective and able to resist various typical attacks, and thus is an excellent candidate for secure image communication application.

10-bit rapid single flux quantum digital-to-analog converter for ac voltage standard

International Nuclear Information System (INIS)

Maezawa, M; Hirayama, F

2008-01-01

Digital-to-analog (D/A) converters based on rapid single flux quantum (RSFQ) technology are under development for ac voltage standard applications. We present design and test results on a prototype 10-bit version integrated on a single chip. The 10-bit chip includes over 6000 Josephson junctions and consumes a bias current exceeding 1 A. To reduce the effects of the high bias current on circuit operation, a custom design method was employed in part and large circuit blocks were divided into smaller ones. The 10-bit chips were fabricated and tested at low speed. The test results suggested that our design approach could manage large bias currents on the order of 1 A per chip

Twin-bit via resistive random access memory in 16 nm FinFET logic technologies

Science.gov (United States)

Shih, Yi-Hong; Hsu, Meng-Yin; King, Ya-Chin; Lin, Chrong Jung

2018-04-01

A via resistive random access memory (RRAM) cell fully compatible with the standard CMOS logic process has been successfully demonstrated for high-density logic nonvolatile memory (NVM) modules in advanced FinFET circuits. In this new cell, the transition metal layers are formed on both sides of a via, given two storage bits per via. In addition to its compact cell area (1T + 14 nm × 32 nm), the twin-bit via RRAM cell features a low operation voltage, a large read window, good data retention, and excellent cycling capability. As fine alignments between mask layers become possible, the twin-bit via RRAM cell is expected to be highly scalable in advanced FinFET technology.

Corrected RMS Error and Effective Number of Bits for Sinewave ADC Tests

International Nuclear Information System (INIS)

Jerome J. Blair

2002-01-01

A new definition is proposed for the effective number of bits of an ADC. This definition removes the variation in the calculated effective bits when the amplitude and offset of the sinewave test signal is slightly varied. This variation is most pronounced when test signals with amplitudes of a small number of code bin widths are applied to very low noise ADC's. The effectiveness of the proposed definition is compared with that of other proposed definitions over a range of signal amplitudes and noise levels

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.)

arXiv FlavBit: A GAMBIT module for computing flavour observables and likelihoods

CERN Document Server

Bernlochner, Florian U.; Dal, Lars A.; Farmer, Ben; Jackson, Paul; Kvellestad, Anders; Mahmoudi, Farvah; Putze, Antje; Rogan, Christopher; Scott, Pat; Serra, Nicola; Weniger, Christoph; White, Martin

2017-11-21

Flavour physics observables are excellent probes of new physics up to very high energy scales. Here we present FlavBit, the dedicated flavour physics module of the global-fitting package GAMBIT. FlavBit includes custom implementations of various likelihood routines for a wide range of flavour observables, including detailed uncertainties and correlations associated with LHCb measurements of rare, leptonic and semileptonic decays of B and D mesons, kaons and pions. It provides a generalised interface to external theory codes such as SuperIso, allowing users to calculate flavour observables in and beyond the Standard Model, and then test them in detail against all relevant experimental data. We describe FlavBit and its constituent physics in some detail, then give examples from supersymmetry and effective field theory illustrating how it can be used both as a standalone library for flavour physics, and within GAMBIT.

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.

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

A Preliminary Study on the Containment Integrity following BIT Removal for Kori NPP Unit 3,4

Energy Technology Data Exchange (ETDEWEB)

Song, Dong Soo; Byun, Choong Sup [KEPRI, Nuclear Power Generation Laboratory, Daejeon (Korea, Republic of); Jo, Jong Young [ENERGEO Inc., Sungnam (Korea, Republic of)

2008-05-15

The Boron Injection Tank (BIT) is to provide high concentrated boric acid to the reactor in order to mitigate the consequences of postulated Main Steam Line Break accidents (MSLB). Although BIT plays an important role in mitigating the accident, high concentration of 20,000ppm causes valve leakage, pipe clog, precipitation and continuous heat tracing have to be provided. This paper is for the feasibility study of containment integrity using CONTEMPT code for BIT removal of Kori Nuclear Power Plant (NPP) Unit 3, 4.

A Preliminary Study on the Containment Integrity following BIT Removal for Kori NPP Unit 3,4

International Nuclear Information System (INIS)

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

2008-01-01

The Boron Injection Tank (BIT) is to provide high concentrated boric acid to the reactor in order to mitigate the consequences of postulated Main Steam Line Break accidents (MSLB). Although BIT plays an important role in mitigating the accident, high concentration of 20,000ppm causes valve leakage, pipe clog, precipitation and continuous heat tracing have to be provided. This paper is for the feasibility study of containment integrity using CONTEMPT code for BIT removal of Kori Nuclear Power Plant (NPP) Unit 3, 4

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 ...

Compact battery-less information terminal (CoBIT) for location-based support systems

Science.gov (United States)

Nishimura, Takuichi; Itoh, Hideo; Yamamoto, Yoshinobu; Nakashima, Hideyuki

2002-06-01

The target of ubiquitous computing environment is to support users to get necessary information and services in a situation-dependent form. Therefore, we propose a location-based information support system by using Compact Battery-less Information Terminal (CoBIT). A CoBIT can communicate with the environmental system and with the user by only the energy supply from the environment. It has a solar cell and get a modulated light from an environmental optical beam transmitter. The current from the solar cell is directly (or through passive circuit) introduced into an earphone, which generates sound for the user. The current is also used to make vibration, LED signal or electrical stimulus on the skin. The sizes of CoBITs are about 2cm in diameter, 3cm in length, which can be hanged on ears conveniently. The cost of it would be only about 1 dollar if produced massively. The CoBIT also has sheet type corner reflector, which reflect optical beam back in the direction of the light source. Therefore the environmental system can easily detect the terminal position and direction as well as some simple signs from the user by multiple cameras with infra-red LEDs. The system identifies the sign by the modulated patterns of the reflected light, which the user makes by occluding the reflector by hand. The environmental system also recognizes other objects using other sensors and displays video information on a nearby monitor in order to realize situated support.

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

Higher rates of sex evolve in spatially heterogeneous environments.

Science.gov (United States)

Becks, Lutz; Agrawal, Aneil F

2010-11-04

The evolution and maintenance of sexual reproduction has puzzled biologists for decades. Although this field is rich in hypotheses, experimental evidence is scarce. Some important experiments have demonstrated differences in evolutionary rates between sexual and asexual populations; other experiments have documented evolutionary changes in phenomena related to genetic mixing, such as recombination and selfing. However, direct experiments of the evolution of sex within populations are extremely rare (but see ref. 12). Here we use the rotifer, Brachionus calyciflorus, which is capable of both sexual and asexual reproduction, to test recent theory predicting that there is more opportunity for sex to evolve in spatially heterogeneous environments. Replicated experimental populations of rotifers were maintained in homogeneous environments, composed of either high- or low-quality food habitats, or in heterogeneous environments that consisted of a mix of the two habitats. For populations maintained in either type of homogeneous environment, the rate of sex evolves rapidly towards zero. In contrast, higher rates of sex evolve in populations experiencing spatially heterogeneous environments. The data indicate that the higher level of sex observed under heterogeneity is not due to sex being less costly or selection against sex being less efficient; rather sex is sufficiently advantageous in heterogeneous environments to overwhelm its inherent costs. Counter to some alternative theories for the evolution of sex, there is no evidence that genetic drift plays any part in the evolution of sex in these populations.

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)

Variable Rate, Adaptive Transform Tree Coding Of Images

Science.gov (United States)

Pearlman, William A.

1988-10-01

A tree code, asymptotically optimal for stationary Gaussian sources and squared error distortion [2], is used to encode transforms of image sub-blocks. The variance spectrum of each sub-block is estimated and specified uniquely by a set of one-dimensional auto-regressive parameters. The expected distortion is set to a constant for each block and the rate is allowed to vary to meet the given level of distortion. Since the spectrum and rate are different for every block, the code tree differs for every block. Coding simulations for target block distortion of 15 and average block rate of 0.99 bits per pel (bpp) show that very good results can be obtained at high search intensities at the expense of high computational complexity. The results at the higher search intensities outperform a parallel simulation with quantization replacing tree coding. Comparative coding simulations also show that the reproduced image with variable block rate and average rate of 0.99 bpp has 2.5 dB less distortion than a similarly reproduced image with a constant block rate equal to 1.0 bpp.

16QAM transmission with 5.2 bits/s/Hz spectral efficiency over transoceanic distance.

Science.gov (United States)

Zhang, H; Cai, J-X; Batshon, H G; Davidson, C R; Sun, Y; Mazurczyk, M; Foursa, D G; Pilipetskii, A; Mohs, G; Bergano, Neal S

2012-05-21

We transmit 160 x 100 G PDM RZ 16 QAM channels with 5.2 bits/s/Hz spectral efficiency over 6,860 km. There are more than 3 billion 16 QAM symbols, i.e., 12 billion bits, processed in total. Using coded modulation and iterative decoding between a MAP decoder and an LDPC based FEC all channels are decoded with no remaining errors.

Terahertz wave manipulation based on multi-bit coding artificial electromagnetic surfaces

Science.gov (United States)

Li, Jiu-Sheng; Zhao, Ze-Jiang; Yao, Jian-Quan

2018-05-01

A polarization insensitive multi-bit coding artificial electromagnetic surface is proposed for terahertz wave manipulation. The coding artificial electromagnetic surfaces composed of four-arrow-shaped particles with certain coding sequences can generate multi-bit coding in the terahertz frequencies and manipulate the reflected terahertz waves to the numerous directions by using of different coding distributions. Furthermore, we demonstrate that our coding artificial electromagnetic surfaces have strong abilities to reduce the radar cross section with polarization insensitive for TE and TM incident terahertz waves as well as linear-polarized and circular-polarized terahertz waves. This work offers an effectively strategy to realize more powerful manipulation of terahertz wave.

Entropy of Bit-Stuffing-Induced Measures for Two-Dimensional Checkerboard Constraints

DEFF Research Database (Denmark)

Forchhammer, Søren; Vaarby, Torben Strange

2007-01-01

A modified bit-stuffing scheme for two-dimensional (2-D) checkerboard constraints is introduced. The entropy of the scheme is determined based on a probability measure defined by the modified bit-stuffing. Entropy results of the scheme are given for 2-D constraints on a binary alphabet....... The constraints considered are 2-D RLL (d, infinity) for d = 2, 3 and 4 as well as for the constraint with a minimum 1-norm distance of 3 between Is. For these results the entropy is within 1-2% of an upper bound on the capacity for the constraint. As a variation of the scheme, periodic merging arrays are also...

Pulse Sign Separation Technique for the Received Bits in Wireless Ultra-Wideband Combination Approach

Directory of Open Access Journals (Sweden)

Rashid A. Fayadh

2014-01-01

Full Text Available When receiving high data rate in ultra-wideband (UWB technology, many users have experienced multiple-user interference and intersymbol interference in the multipath reception technique. Structures have been proposed for implementing rake receivers to enhance their capabilities by reducing the bit error probability (Pe, thereby providing better performances by indoor and outdoor multipath receivers. As a result, several rake structures have been proposed in the past to reduce the number of resolvable paths that must be estimated and combined. To achieve this aim, we suggest two maximal ratio combiners based on the pulse sign separation technique, such as the pulse sign separation selective combiner (PSS-SC and the pulse sign separation partial combiner (PSS-PC to reduce complexity with fewer fingers and to improve the system performance. In the combiners, a comparator was added to compare the positive quantity of positive pulses and negative quantities of negative pulses to decide whether the transmitted bit was 1 or 0. The Pe was driven by simulation for multipath environments for impulse radio time-hopping binary phase shift keying (TH-BPSK modulation, and the results were compared with those of conventional selective combiners (C-SCs and conventional partial combiners (C-PCs.

A Novel Multiple-Bits Collision Attack Based on Double Detection with Error-Tolerant Mechanism

Directory of Open Access Journals (Sweden)

Ye Yuan

2018-01-01

Full Text Available Side-channel collision attacks are more powerful than traditional side-channel attack without knowing the leakage model or establishing the model. Most attack strategies proposed previously need quantities of power traces with high computational complexity and are sensitive to mistakes, which restricts the attack efficiency seriously. In this paper, we propose a multiple-bits side-channel collision attack based on double distance voting detection (DDVD and also an improved version, involving the error-tolerant mechanism, which can find all 120 relations among 16 key bytes when applied to AES (Advanced Encryption Standard algorithm. In addition, we compare our collision detection method called DDVD with the Euclidean distance and the correlation-enhanced collision method under different intensity of noise, which indicates that our detection technique performs better in the circumstances of noise. Furthermore, 4-bit model of our collision detection method is proven to be optimal in theory and in practice. Meanwhile the corresponding practical attack experiments are also performed on a hardware implementation of AES-128 on FPGA board successfully. Results show that our strategy needs less computation time but more traces than LDPC method and the online time for our strategy is about 90% less than CECA and 96% less than BCA with 90% success rate.

Demonstrating Multi-bit Magnetic Memory in the Fe8 High Spin Molecule by Muon Spin Rotation

OpenAIRE

Shafir, Oren; Keren, Amit; Maegawa, Satoru; Ueda, Miki; Amato, Alex; Baines, Chris

2005-01-01

We developed a method to detect the quantum nature of high spin molecules using muon spin rotation, and a three-step field cycle ending always with the same field. We use this method to demonstrate that the Fe8 molecule can remember 6 (possibly 8) different histories (bits). A wide range of fields can be used to write a particular bit, and the information is stored in discrete states. Therefore, Fe8 can be used as a model compound for Multi-bit Magnetic Memory. Our experiment also paves the w...

Directed self-assembly of block copolymers for use in bit patterned media fabrication

International Nuclear Information System (INIS)

Griffiths, Rhys Alun; Vijayaraghavan, Aravind; Thomson, Thomas; Williams, Aled; Oakland, Chloe; Roberts, Jonathan

2013-01-01

Reduction of the bit size in conventional magnetic recording media is becoming increasingly difficult due to the superparamagnetic limit. Bit patterned media (BPM) has been proposed as a replacement technology as it will enable hard disk areal densities to increase past 1 Tb in −2 . Block copolymer directed self-assembly (BCP DSA) is the leading candidate for forming BPM due to its ability to create uniform patterns over macroscopic areas. Here we review the latest research into two different BCP DSA techniques: graphoepitaxy and chemoepitaxy (or chemical prepatterning). In addition to assessing their potential for forming high density bit patterns, we also review current approaches using these techniques for forming servo patterns, which are required for hard disk drive (HDD) operation. Finally, we review the current state of UV nanoimprint lithography, which is the favoured technique for enabling mass production of BPM HDDs. (topical review)

Error-free 5.1 Tbit/s data generation on a single-wavelength channel using a 1.28 Tbaud symbol rate

DEFF Research Database (Denmark)

Mulvad, Hans Christian Hansen; Galili, Michael; Oxenløwe, Leif Katsuo

2009-01-01

We demonstrate a record bit rate of 5.1 Tbit/s on a single wavelength using a 1.28 Tbaud OTDM symbol rate, DQPSK data-modulation, and polarisation-multiplexing. Error-free performance (BER......We demonstrate a record bit rate of 5.1 Tbit/s on a single wavelength using a 1.28 Tbaud OTDM symbol rate, DQPSK data-modulation, and polarisation-multiplexing. Error-free performance (BER...

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...

0.5 V and 0.43 pJ/bit Capacitive Sensor Interface for Passive Wireless Sensor Systems.

Science.gov (United States)

Beriain, Andoni; Gutierrez, Iñigo; Solar, Hector; Berenguer, Roc

2015-08-28

This paper presents an ultra low-power and low-voltage pulse-width modulation based ratiometric capacitive sensor interface. The interface was designed and fabricated in a standard 90 nm CMOS 1P9M technology. The measurements show an effective resolution of 10 bits using 0.5 V of supply voltage. The active occupied area is only 0.0045 mm2 and the Figure of Merit (FOM), which takes into account the energy required per conversion bit, is 0.43 pJ/bit. Furthermore, the results show low sensitivity to PVT variations due to the proposed ratiometric architecture. In addition, the sensor interface was connected to a commercial pressure transducer and the measurements of the resulting complete pressure sensor show a FOM of 0.226 pJ/bit with an effective linear resolution of 7.64 bits. The results validate the use of the proposed interface as part of a pressure sensor, and its low-power and low-voltage characteristics make it suitable for wireless sensor networks and low power consumer electronics.

An 8 bit 1 MS/s SAR ADC with 7.72-ENOB

Science.gov (United States)

Duan, Jihai; Zhu, Zhiyong; Deng, Jinli; Xu, Weilin

2017-08-01

This paper presents a low power 8-bit 1 MS/s SAR ADC with 7.72-bit ENOB. Without an op-amp, an improved segmented capacitor DAC is proposed to reduce the capacitance and the chip area. A dynamic latch comparator with output offset voltage storage technology is used to improve the precision. Adding an extra positive feedback in the latch is to increase the speed. What is more, two pairs of CMOS switches are utilized to eliminate the kickback noise introduced by the latch. The proposed SAR ADC was fabricated in SMIC 0.18 {{μ }}{{m}} CMOS technology. The measured results show that this design achieves an SFDR of 61.8 dB and an ENOB of 7.72 bits, and it consumes 67.5 μW with the FOM of 312 fJ/conversion-step at 1 MS/s sample under 1.8 V power supply. Project supported by the National Natural Science Foundation of China (Nos. 61161003, 61264001, 61166004) and the Guangxi Key Laboratory of Precision Navigation Technology and Application Foundation (No. DH201501).

Comparison of statistical sampling methods with ScannerBit, the GAMBIT scanning module

Energy Technology Data Exchange (ETDEWEB)

Martinez, Gregory D. [University of California, Physics and Astronomy Department, Los Angeles, CA (United States); McKay, James; Scott, Pat [Imperial College London, Department of Physics, Blackett Laboratory, London (United Kingdom); Farmer, Ben; Conrad, Jan [AlbaNova University Centre, Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Stockholm University, Department of Physics, Stockholm (Sweden); Roebber, Elinore [McGill University, Department of Physics, Montreal, QC (Canada); Putze, Antje [LAPTh, Universite de Savoie, CNRS, Annecy-le-Vieux (France); Collaboration: The GAMBIT Scanner Workgroup

2017-11-15

We introduce ScannerBit, the statistics and sampling module of the public, open-source global fitting framework GAMBIT. ScannerBit provides a standardised interface to different sampling algorithms, enabling the use and comparison of multiple computational methods for inferring profile likelihoods, Bayesian posteriors, and other statistical quantities. The current version offers random, grid, raster, nested sampling, differential evolution, Markov Chain Monte Carlo (MCMC) and ensemble Monte Carlo samplers. We also announce the release of a new standalone differential evolution sampler, Diver, and describe its design, usage and interface to ScannerBit. We subject Diver and three other samplers (the nested sampler MultiNest, the MCMC GreAT, and the native ScannerBit implementation of the ensemble Monte Carlo algorithm T-Walk) to a battery of statistical tests. For this we use a realistic physical likelihood function, based on the scalar singlet model of dark matter. We examine the performance of each sampler as a function of its adjustable settings, and the dimensionality of the sampling problem. We evaluate performance on four metrics: optimality of the best fit found, completeness in exploring the best-fit region, number of likelihood evaluations, and total runtime. For Bayesian posterior estimation at high resolution, T-Walk provides the most accurate and timely mapping of the full parameter space. For profile likelihood analysis in less than about ten dimensions, we find that Diver and MultiNest score similarly in terms of best fit and speed, outperforming GreAT and T-Walk; in ten or more dimensions, Diver substantially outperforms the other three samplers on all metrics. (orig.)

Configurable Electronics with Low Noise and 14-bit Dynamic Range for Photodiode-based Photon Detectors

CERN Document Server

Müller, H; Yin, Z; Zhou, D; Cao, X; Li, Q; Liu, Y; Zou, F; Skaali, B; Awes, T C

2006-01-01

We describe the principles and measured performance characteristics of custom configurable 32-channel shaper/digitizer Front End Electronics (FEE) cards with 14-bit dynamic range for use with gain-adjustable photon detectors. The electronics has been designed for the PHOS calorimeter of ALICE with avalanche photodiode (APD) readout operated at -25 C ambient temperature and a signal shaping time of $1 {\\mu}s$. The electronics has also been adopted by the EMCal detector of ALICE with the same APD readout, but operated at an ambient temperature of +20 C and with a shaping time of 100ns. The CR-RC2 signal shapers on the FEE cards are implemented in discrete logic on a 10-layer board with two shaper sections for each input channel. The two shaper sections with gain ratio of 16:1 are digitized by 10-bit ADCs and provide an effective dynamic range of 14 bits. Gain adjustment for each individual APD is available through 32 bias voltage control registers of 10-bit range. The fixed gains and shaping times of the pole-z...

Enabling Higher Data Rates for Planetary Science Missions

Science.gov (United States)

Deutsch, L. J.; Townes, S. A.; Lazio, J.; Bell, D. J.; Chahat, N. E.; Kovalik, J. M.; Kuperman, I.; Sauder, J.; Liebrecht, P. E.

2017-12-01

The data rate from deep space spacecraft has increased by more than 10 orders of magnitude since the first lunar missions in the 1960s. The demand for increased data rates has stemmed from the increasing sophistication of the science questions being addressed and the concomitant increase in the complexity of the missions themselves (from fly-by to orbit to land and rove). Projections for the next few decades suggest the demand for data rates for deep space missions will continue to increase by approximately one order of magnitude every decade, driven by these same factors. Achieving higher data rates requires a partnership between the spacecraft and the ground system. We describe a series of technology developments for flight telecommunications systems, both at radio frequency (RF) and optical, to enable spacecraft to transmit and receive larger data volumes. These technology developments include deployable high gain antennas for small spacecraft, re-programmable software-defined radios, and optical communication packages designed for CubeSat form factors. The intent is that these developments would provide enhancements in capability for both spacecraft-Earth and spacecraft-spacecraft telecommunications. We also describe the future planning for NASA's Deep Space Network (DSN), which remains the prime conduit for data from all planetary science missions. Through a combination of new antennas and backends being installed over the next five years and incorporation of optical communications, the DSN aims to ensure that the historical improvements in data rates and volumes will continue for many decades. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

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.

12-bit 32 channel 500 MS/s low-latency ADC for particle accelerators real-time control

Science.gov (United States)

Karnitski, Anton; Baranauskas, Dalius; Zelenin, Denis; Baranauskas, Gytis; Zhankevich, Alexander; Gill, Chris

2017-09-01

Particle beam control systems require real-time low latency digital feedback with high linearity and dynamic range. Densely packed electronic systems employ high performance multichannel digitizers causing excessive heat dissipation. Therefore, low power dissipation is another critical requirement for these digitizers. A described 12-bit 500 MS/s ADC employs a sub-ranging architecture based on a merged sample & hold circuit, a residue C-DAC and a shared 6-bit flash core ADC. The core ADC provides a sequential coarse and fine digitization featuring a latency of two clock cycles. The ADC is implemented in a 28 nm CMOS process and consumes 4 mW of power per channel from a 0.9 V supply (interfacing and peripheral circuits are excluded). Reduced power consumption and small on-chip area permits the implementation of 32 ADC channels on a 10.7 mm2 chip. The ADC includes a JESD204B standard compliant output data interface operated at the 7.5 Gbps/ch rate. To minimize the data interface related time latency, a special feature permitting to bypass the JESD204B interface is built in. DoE Phase I Award Number: DE-SC0017213.

Evaluation of Giga-bit Ethernet instrumentation for SalSA electronics readout

International Nuclear Information System (INIS)

Varner, Gary S.; Murakami, Laine; Ridley, David; Zhu Chaopin; Gorham, Peter

2005-01-01

An instrumentation prototype for acquiring high-speed transient data from an array of high bandwidth antennas is presented. Multi-kilometer cable runs complicate acquisition of such large bandwidth radio signals from an extensive antenna array. Solutions using analog fiber optic links are being explored though are very expensive. We propose an inexpensive solution that allows for individual operation of each antenna element, operating at potentially high local self-trigger rates. Digitized data packets are transmitted to the surface via commercially available Giga-bit Ethernet hardware. Events are then reconstructed on a computer farm by sorting the received packets using standard networking gear, eliminating the need for custom, very high speed trigger hardware. Such a system is completely scalable and leverages the enormous capital investment made by the telecommunications industry. Test results from a demonstration prototype are presented

Faithful remote state preparation using finite classical bits and a nonmaximally entangled state

International Nuclear Information System (INIS)

Ye Mingyong; Zhang Yongsheng; Guo Guangcan

2004-01-01

We present many ensembles of states that can be remotely prepared by using minimum classical bits from Alice to Bob and their previously shared entangled state and prove that we have found all the ensembles in two-dimensional case. Furthermore we show that any pure quantum state can be remotely and faithfully prepared by using finite classical bits from Alice to Bob and their previously shared nonmaximally entangled state though no faithful quantum teleportation protocols can be achieved by using a nonmaximally entangled state

A 12-bit 40 MS/s pipelined ADC with over 80 dB SFDR

Energy Technology Data Exchange (ETDEWEB)

Wei Qi; Yin Xiumei; Han Dandan; Yang Huazhong, E-mail: q-wei05@mails.tsinghua.edu.c [Department of Electronic Engineering, Tsinghua University, Beijing 100084 (China)

2010-02-15

This paper describes a 12-bit 40 MS/s calibration-free pipelined analog-to-digital converter (ADC), which is optimized for high spurious free dynamic range (SFDR) performance and low power dissipation. With a 4.9 MHz sine wave input, the prototype ADC implemented in a 0.18-{mu}m 1P6M CMOS process shows measured differential nonlinearity and integral nonlinearity within 0.78 and 1.32 least significant bits at the 12-bit level without any trimming or calibration. The ADC, with a total die area of 3.1 x 2.1 mm{sup 2}, demonstrates a maximum signal-to-noise distortion ratio (SNDR) and SFDR of 66.32 and 83.38 dB, respectively, at a 4.9 MHz analog input and a power consumption of 102 mW from a 1.8 V supply. (semiconductor integrated circuits)

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...

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...

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...

DarkBit. A GAMBIT module for computing dark matter observables and likelihoods

Energy Technology Data Exchange (ETDEWEB)

Bringmann, Torsten; Dal, Lars A. [University of Oslo, Department of Physics, Oslo (Norway); Conrad, Jan; Edsjoe, Joakim; Farmer, Ben [AlbaNova University Centre, Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden); Stockholm University, Department of Physics, Stockholm (Sweden); Cornell, Jonathan M. [McGill University, Department of Physics, Montreal, QC (Canada); Kahlhoefer, Felix; Wild, Sebastian [DESY, Hamburg (Germany); Kvellestad, Anders; Savage, Christopher [NORDITA, Stockholm (Sweden); Putze, Antje [LAPTh, Universite de Savoie, CNRS, Annecy-le-Vieux (France); Scott, Pat [Blackett Laboratory, Imperial College London, Department of Physics, London (United Kingdom); Weniger, Christoph [University of Amsterdam, GRAPPA, Institute of Physics, Amsterdam (Netherlands); White, Martin [University of Adelaide, Department of Physics, Adelaide, SA (Australia); Australian Research Council Centre of Excellence for Particle Physics at the Tera-scale, Parkville (Australia); Collaboration: The GAMBIT Dark Matter Workgroup

2017-12-15

We introduce DarkBit, an advanced software code for computing dark matter constraints on various extensions to the Standard Model of particle physics, comprising both new native code and interfaces to external packages. This release includes a dedicated signal yield calculator for gamma-ray observations, which significantly extends current tools by implementing a cascade-decay Monte Carlo, as well as a dedicated likelihood calculator for current and future experiments (gamLike). This provides a general solution for studying complex particle physics models that predict dark matter annihilation to a multitude of final states. We also supply a direct detection package that models a large range of direct detection experiments (DDCalc), and that provides the corresponding likelihoods for arbitrary combinations of spin-independent and spin-dependent scattering processes. Finally, we provide custom relic density routines along with interfaces to DarkSUSY, micrOMEGAs, and the neutrino telescope likelihood package nulike. DarkBit is written in the framework of the Global And Modular Beyond the Standard Model Inference Tool (GAMBIT), providing seamless integration into a comprehensive statistical fitting framework that allows users to explore new models with both particle and astrophysics constraints, and a consistent treatment of systematic uncertainties. In this paper we describe its main functionality, provide a guide to getting started quickly, and show illustrative examples for results obtained with DarkBit (both as a stand-alone tool and as a GAMBIT module). This includes a quantitative comparison between two of the main dark matter codes (DarkSUSY and micrOMEGAs), and application of DarkBit's advanced direct and indirect detection routines to a simple effective dark matter model. (orig.)

Diseño de multiplicador de 64 bits utilizando la técnica de barrido superpuesto

OpenAIRE

Montalvo Ramírez, Luis

1987-01-01

Se presenta el desarrollo del novel algoritmo de multiplicación por barrido superpuesto de 3-bits, así como también los aspectos importantes del diseño de la arquitectura, redes lógicas y layout de un multiplicador de 64-bits utilizando como caso de estudio.

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

A new approach to quantum oblivious transfer and quantum bit commitment

International Nuclear Information System (INIS)

Dang, Minh-Dung; Bellot, P.

2005-01-01

Full text: In this communication, we present our works on building quantum OT and BC protocols. The starting idea is to use non-orthogonal instead of orthogonal quantum states (|0>, |1>) to encode classical bits. Based on this coding, we propose a Weak Quantum Oblivious Transfer protocol, and by extending Crepeau's works, we can create a Quantum One-out-of-two Oblivious Transfer protocol that is secure against Alice and Bob cheating. A regular Bit Commitment protocol can then be built from our OOT protocol. Although the unconditional security of our BC and OOT protocols seem to contradict Mayers and Lo-Chau theorems, we conjecture that our protocols do not fit in the models of Mayers and Lo-Chau. (author)

United States private schools have higher rates of exemptions to school immunization requirements than public schools.

Science.gov (United States)

Shaw, Jana; Tserenpuntsag, Boldtsetseg; McNutt, Louise-Anne; Halsey, Neal

2014-07-01

To compare medical, religious, and personal belief immunization exemption rates between private and public schools in US. Exemption rates were calculated using the Centers for Disease Control and Prevention School Immunization Assessment Surveys for the 2009-2010 school year excluding states with incomplete survey data. Standardized exemption rates weighted on enrollments in public and private schools were calculated. Differences in exemption rates between public and private schools were tested using Wilcoxon signed rank test. The overall state exemption rate was higher in US private than public schools, 4.25% (SD 4.27) vs 1.91% (1.67), P = .0001 and private schools had higher exemption rates for all types of exemptions; medical 0.58% (0.71) vs 0.34% (0.34) respectively (P = .0004), religious 2.09% (3.14) vs 0.83% (1.05) respectively (P = .0001), and personal belief 6.10% (4.12) vs 2.79% (1.57), respectively (P = .006). Overall exemption rates were significantly higher in states that allowed personal belief exemptions. Exemption rates were significantly higher in US private than in public schools. Children attending private schools may be at higher risk of vaccine-preventable diseases than public school children. Copyright © 2014 Elsevier Inc. All rights reserved.

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....

Digitally Controlled Offline Converter with Galvanic Isolation Based on an 8-bit Microcontroller

DEFF Research Database (Denmark)

Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.

2007-01-01

This paper presents an offline AC/DC converter with digital control and galvanic isolation that can be implemented using cheap commercially available components. An ATMEL ATTiny26 8-bit microcontroller is used to control the converter. The microcontroller is placed on the secondary side of the co......This paper presents an offline AC/DC converter with digital control and galvanic isolation that can be implemented using cheap commercially available components. An ATMEL ATTiny26 8-bit microcontroller is used to control the converter. The microcontroller is placed on the secondary side...

Multi-bits memory cell using degenerated magnetic states in a synthetic antiferromagnetic reference layer

International Nuclear Information System (INIS)

Fukushima, Akio; Yakushiji, Kay; Konoto, Makoto; Kubota, Hitoshi; Imamura, Hiroshi; Yuasa, Shinji

2016-01-01

We newly developed a magnetic memory cell having multi-bit function. The memory cell composed of a perpendicularly magnetized magnetic tunnel junction (MB-pMTJ) and a synthetic antiferromagnetic reference layer. The multi-bit function is realized by combining the freedom of states of the magnetic free layer and that in the antiferromagnetically coupled reference layer. The structure of the reference layer is (FeB/Ta/[Co/Pt]_3)/Ru/([Co/Pt]_6); the top and the bottom layers are coupled through Ru layer where the reference layer has two degrees of freedom of a head-to-head and a bottom-to-bottom magnetic configuration. A four-state memory cell is realized by combination of both degrees of freedom. The states in the reference layer however is hardly detected by the total resistance of MB-pMTJ, because the magnetoresistance effect in the reference layer is negligibly small. That implies that the resistance values for the different states in the reference layer are degenerated. On the other hand, the two different states in the reference layer bring different stray fields to the free layer, which generate two different minor loop with different switching fields. Therefore, the magnetic states in the reference layer can be differentiated by the two-step reading, before and after applying the appropriately pulsed magnetic field which can identify the initial state in the reference layer. This method is similar to distinguishing different magnetic states in an in-plane magnetized spin-valve element. We demonstrated that four different states in the MB-pMTJ can be distinguished by the two-step read-out. The important feature of the two-step reading is a practically large operation margins (large resistance change in reading) which is equal to that of a single MTJ. Even though the two-step reading is a destructive method by which 50% of the magnetic state is changed, this MB-pMTJ is promising for high density non-volatile memory cell with a minor cost of operation speed

A New Scrambling Evaluation Scheme Based on Spatial Distribution Entropy and Centroid Difference of Bit-Plane

Science.gov (United States)

Zhao, Liang; Adhikari, Avishek; Sakurai, Kouichi

Watermarking is one of the most effective techniques for copyright protection and information hiding. It can be applied in many fields of our society. Nowadays, some image scrambling schemes are used as one part of the watermarking algorithm to enhance the security. Therefore, how to select an image scrambling scheme and what kind of the image scrambling scheme may be used for watermarking are the key problems. Evaluation method of the image scrambling schemes can be seen as a useful test tool for showing the property or flaw of the image scrambling method. In this paper, a new scrambling evaluation system based on spatial distribution entropy and centroid difference of bit-plane is presented to obtain the scrambling degree of image scrambling schemes. Our scheme is illustrated and justified through computer simulations. The experimental results show (in Figs. 6 and 7) that for the general gray-scale image, the evaluation degree of the corresponding cipher image for the first 4 significant bit-planes selection is nearly the same as that for the 8 bit-planes selection. That is why, instead of taking 8 bit-planes of a gray-scale image, it is sufficient to take only the first 4 significant bit-planes for the experiment to find the scrambling degree. This 50% reduction in the computational cost makes our scheme efficient.

A 16-bit sigma-delta modulator applied in micro-machined inertial sensors

Science.gov (United States)

Honglin, Xu; Qiang, Fu; Hongna, Liu; Liang, Yin; Pengfei, Wang; Xiaowei, Liu

2014-04-01

A fourth-order low-distortion low-pass sigma-delta (ΣΔ) modulator is presented for micro-machined inertial sensors. The proposed single-loop single-bit feedback modulator is optimized with a feed-forward path to decrease the nonlinearities and power consumption. The IC is implemented in a standard 0.6 μm CMOS technology and operates at a sampling frequency of 3.846 MHz. The chip area is 2.12 mm2 with 23 pads. The experimental results indicate a signal-to-noise ratio (SNR) of 100 dB and dynamic range (DR) of 103 dB at an oversampling rate (OSR) of 128 with the input signal amplitude of -3.88 dBFS at 9.8 kHz; the power consumption is 15 mW at a 5 V supply.

A 16-bit sigma–delta modulator applied in micro-machined inertial sensors

International Nuclear Information System (INIS)

Xu Honglin; Fu Qiang; Liu Hongna; Yin Liang; Wang Pengfei; Liu Xiaowei

2014-01-01

A fourth-order low-distortion low-pass sigma–delta (ΣΔ) modulator is presented for micro-machined inertial sensors. The proposed single-loop single-bit feedback modulator is optimized with a feed-forward path to decrease the nonlinearities and power consumption. The IC is implemented in a standard 0.6 μm CMOS technology and operates at a sampling frequency of 3.846 MHz. The chip area is 2.12 mm 2 with 23 pads. The experimental results indicate a signal-to-noise ratio (SNR) of 100 dB and dynamic range (DR) of 103 dB at an oversampling rate (OSR) of 128 with the input signal amplitude of −3.88 dBFS at 9.8 kHz; the power consumption is 15 mW at a 5 V supply. (semiconductor integrated circuits)

Vastus Lateralis Motor Unit Firing Rate Is Higher in Women With Patellofemoral Pain.

Science.gov (United States)

Gallina, Alessio; Hunt, Michael A; Hodges, Paul W; Garland, S Jayne

2018-05-01

To compare neural drive, determined from motor unit firing rate, in the vastus medialis and lateralis in women with and without patellofemoral pain. Cross-sectional study. University research laboratory. Women (N=56) 19 to 35 years of age, including 36 with patellofemoral pain and 20 controls. Not applicable. Participants sustained an isometric knee extension contraction at 10% of their maximal voluntary effort for 70 seconds. Motor units (N=414) were identified using high-density surface electromyography. Average firing rate was calculated between 5 and 35 seconds after recruitment for each motor unit. Initial firing rate was the inverse of the first 3 motor unit interspike intervals. In control participants, vastus medialis motor units discharged at higher rates than vastus lateralis motor units (P=.001). This was not observed in women with patellofemoral pain (P=.78) because of a higher discharge rate of vastus lateralis compared with control participants (P=.002). No between-group differences were observed for vastus medialis (P=.93). Similar results were obtained for the initial motor unit firing rate. These findings suggest that women with patellofemoral pain have a higher neural drive to vastus lateralis but not vastus medialis, which may be a contributor of the altered patellar kinematics observed in some studies. The different neural drive may be an adaptation to patellofemoral pain, possibly to compensate for decreased quadriceps force production, or a precursor of patellofemoral pain. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A Fast Multiple Sampling Method for Low-Noise CMOS Image Sensors With Column-Parallel 12-bit SAR ADCs

Directory of Open Access Journals (Sweden)

Min-Kyu Kim

2015-12-01

Full Text Available This paper presents a fast multiple sampling method for low-noise CMOS image sensor (CIS applications with column-parallel successive approximation register analog-to-digital converters (SAR ADCs. The 12-bit SAR ADC using the proposed multiple sampling method decreases the A/D conversion time by repeatedly converting a pixel output to 4-bit after the first 12-bit A/D conversion, reducing noise of the CIS by one over the square root of the number of samplings. The area of the 12-bit SAR ADC is reduced by using a 10-bit capacitor digital-to-analog converter (DAC with four scaled reference voltages. In addition, a simple up/down counter-based digital processing logic is proposed to perform complex calculations for multiple sampling and digital correlated double sampling. To verify the proposed multiple sampling method, a 256 × 128 pixel array CIS with 12-bit SAR ADCs was fabricated using 0.18 μm CMOS process. The measurement results shows that the proposed multiple sampling method reduces each A/D conversion time from 1.2 μs to 0.45 μs and random noise from 848.3 μV to 270.4 μV, achieving a dynamic range of 68.1 dB and an SNR of 39.2 dB.

A 0.7V 7-to-10bit 0-to-2MS/s Flexible SAR ADC for Ultra Low-Power Wireless Sensor Nodes

NARCIS (Netherlands)

Harpe, P.J.A.; Dolmans, G.; Philips, K.J.P.; Groot, de H.W.H.

2012-01-01

This paper presents a flexible SAR ADC in 90nm CMOS for wireless sensor nodes. By supporting resolutions from 7 to 10bit and sample rates from DC to 2MS/s, this design can be used for a variety of applications such as sensor interfacing and receiver frontends. Flexibility is achieved by a

Patterns in the distribution of digital games via BitTorrent

DEFF Research Database (Denmark)

Drachen, Anders; Veitch, Robert W. D.

2013-01-01

The distribution of illegal copies of computer games via digital networks forms the centre in one of the most heated debates in the international games environment, but there is minimal objective information available. Here the results of a large-scale, open-method analysis of the distribution...... of computer games via BitTorrent peer-to-peer file-sharing protocol is presented. 173 games were included, tracked over a period of three months from 2010 to 2011. A total of 12.6 million unique peers were identified across over 200 countries. Analysis indicates that the distribution of illegal copies...... of games follows distinct pattern, e.g., that a few game titles drive the traffic - the 10 most accessed games encompassed 42.7% of the number of peers tracked. The traffic is geographically localised - 20 countries encompassed 76.7% of the total. Geographic patterns in the distribution of BitTorrent peers...

Room temperature solid-state quantum bit with second-long memory

Science.gov (United States)

Kucsko, Georg; Maurer, Peter; Latta, Christian; Hunger, David; Jiang, Liang; Pastawski, Fernando; Yao, Norman; Bennet, Steven; Twitchen, Daniel; Cirac, Ignacio; Lukin, Mikhail

2012-02-01

Realization of stable quantum bits (qubits) that can be prepared and measured with high fidelity and that are capable of storing quantum information for long times exceeding seconds is an outstanding challenge in quantum science and engineering. Here we report on the realization of such a stable quantum bit using an individual ^13C nuclear spin within an isotopically purified diamond crystal at room temperature. Using an electronic spin associated with a nearby Nitrogen Vacancy color center, we demonstrate high fidelity initialization and readout of a single ^13C qubit. Quantum memory lifetime exceeding one second is obtained by using dissipative optical decoupling from the electronic degree of freedom and applying a sequence of radio-frequency pulses to suppress effects from the dipole-dipole interactions of the ^13C spin-bath. Techniques to further extend the quantum memory lifetime as well as the potential applications are also discussed.

Micromagnetic studies for bit patterned media above 2 Tbit/in.2

International Nuclear Information System (INIS)

Zhang Kaiming; Wei Dan

2012-01-01

Bit patterned media (BPM) recording is a candidate for extremely high density magnetic recording. A micromagnetic model is built up to analyze the phase diagram of the correct-write-in condition in BPM above 2 Tb/in. 2 fabricated by lithography or ion irradiation methods. The target of the study is to acquire the relationship between the recording performance and the magnetic properties of the media. The medium includes the polycrystalline grains and grain boundary. In BPM fabricated by lithography with FCT structure, two phase diagrams of the correct-write-in condition are found for the anisotropy angular distribution Δθ, the ratio of tetragonal anisotropy K 22 to uniaxial anisotropy K 1 and the uniaxial anisotropy distribution ΔK 1 . In BPM fabricated by ion irradiation methods, two phase diagrams of the correct-write-in condition are analyzed for the ratio of saturation magnetization M' s /M s , anisotropy field H' k /H k and the exchange field H' ex /H ex in the ion irradiated region and the bit islands. - Research highlights: → Two types of BPM, regular or with irradiated regions, are studied using micromagnetics. → Optimum parameters are found for regular BPM with non-magnetic inter-bit spacing. → Recording phase diagrams versus M s , H k and A * in irradiated regions are found.

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

Characterization of subsurface structure at Soultz HDR field by the triaxial drill-bit VSP; Sanjiku drill bit VSP ho ni yoru Soultz HDR field no chika kozo suitei

Energy Technology Data Exchange (ETDEWEB)

Asanuma, H; Niitsuma, H; Liu, H [Tohoku University, Sendai (Japan); Baria, R

1997-10-22

Triaxial drill-bit VSP (vertical seismic profiling) method is applied to the Soultz HDR (hot dry rock) field, France, where an artificial reservoir is provided inside the bedrock, and the structure inside the rockbed is estimated. An elastic wave detector is installed in the rockbed in this field, and data are acquired having frequency components up to approximately 1kHz. The trajectory of particles due to excavation noise is analyzed, and it is found that the drill-bit is the primary source of noise during excavation and that the SV-wave dominates in the emitted noise. Estimating the subsurface structure aided by the principle of the triaxial drill-bit VSP method, the lower part is detected of the artificial reservoir formed by hydraulic fracturing. As is reported in this paper, when the principle of the subject VSP method is considered, it has to be said that it is quite difficult to employ this method to extensively estimate the subsurface structure on the basis of measurements of the inside of the rockbed. There is a plan for a future study of a technique for accurately and extensively estimating subsurface structures by use of a small number of sensors. 8 refs., 7 figs.

Fast Rate Estimation for RDO Mode Decision in HEVC

Directory of Open Access Journals (Sweden)

Maxim P. Sharabayko

2014-12-01

Full Text Available The latter-day H.265/HEVC video compression standard is able to provide two-times higher compression efficiency compared to the current industrial standard, H.264/AVC. However, coding complexity also increased. The main bottleneck of the compression process is the rate-distortion optimization (RDO stage, as it involves numerous sequential syntax-based binary arithmetic coding (SBAC loops. In this paper, we present an entropy-based RDO estimation technique for H.265/HEVC compression, instead of the common approach based on the SBAC. Our RDO implementation reduces RDO complexity, providing an average bit rate overhead of 1.54%. At the same time, elimination of the SBAC from the RDO estimation reduces block interdependencies, thus providing an opportunity for the development of the compression system with parallel processing of multiple blocks of a video frame.

FY 1975 Report on results of Sunshine Project. Development of techniques of digging high-temperature beds (Development of solid bits and air-friction bearings); 1975 nendo koon chiso kussaku gijutsu no kaihatsu. Solid bit oyobi air friction bearing no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1976-03-31

A combination of superhard alloy and diamond powder has been widely used as the solid type edge. The solid type with only a superhard alloy edge is no better than the traditional metal bit. It is ironical to admit that one of the most important items in the development of solid bits for digging high-temperature beds is not related to high temperature itself but development of highly efficient, long serviceable bits, growing out of the inefficient digging mechanisms for the conventional solid bits. It is considered that use of a superhard alloy edge is disadvantageous for digging hard rocks in the so-called scratching manner, for the two major reasons: (1) a superhard alloy is certainly resistant to wear, but nothing to that of diamond, and (2) it is homogeneous and lacks directional properties, such as the cleavage plane of diamond, which is effective for cutting. This project is aimed at development, on a trial basis, and eventual commercialization of new types of solid bits serviceable for extended periods by drastically improving suerhard alloys to provide them with new structures, e.g., those corresponding to the crystal axes of diamond, and also introducing a concept of crushing. (NEDO)

Cheat-sensitive commitment of a classical bit coded in a block of mxn round-trip qubits

International Nuclear Information System (INIS)

Shimizu, Kaoru; Fukasaka, Hiroyuki; Tamaki, Kiyoshi; Imoto, Nobuyuki

2011-01-01

This paper proposes a quantum protocol for a cheat-sensitive commitment of a classical bit. Alice, the receiver of the bit, can examine dishonest Bob, who changes or postpones his choice. Bob, the sender of the bit, can examine dishonest Alice, who violates concealment. For each round-trip case, Alice sends one of two spin states |S±> by choosing basis S at random from two conjugate bases X and Y. Bob chooses basis C is an element of {X,Y} to perform a measurement and returns a resultant state |C±>. Alice then performs a measurement with the other basis R (≠S) and obtains an outcome |R±>. In the opening phase, she can discover dishonest Bob, who unveils a wrong basis with a faked spin state, or Bob can discover dishonest Alice, who infers basis C but destroys |C±> by setting R to be identical to S in the commitment phase. If a classical bit is coded in a block of mxn qubit particles, impartial examinations and probabilistic security criteria can be achieved.

Cheat-sensitive commitment of a classical bit coded in a block of mxn round-trip qubits

Energy Technology Data Exchange (ETDEWEB)

Shimizu, Kaoru; Fukasaka, Hiroyuki [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); Tamaki, Kiyoshi [NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan); National Institute of Information and Communications Technology (NICT), 4-2-1 Nukui-kitamachi, Koganei, Tokyo 184-8795 (Japan); Imoto, Nobuyuki [Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531 (Japan)

2011-08-15

This paper proposes a quantum protocol for a cheat-sensitive commitment of a classical bit. Alice, the receiver of the bit, can examine dishonest Bob, who changes or postpones his choice. Bob, the sender of the bit, can examine dishonest Alice, who violates concealment. For each round-trip case, Alice sends one of two spin states |S{+-}> by choosing basis S at random from two conjugate bases X and Y. Bob chooses basis C is an element of {l_brace}X,Y{r_brace} to perform a measurement and returns a resultant state |C{+-}>. Alice then performs a measurement with the other basis R ({ne}S) and obtains an outcome |R{+-}>. In the opening phase, she can discover dishonest Bob, who unveils a wrong basis with a faked spin state, or Bob can discover dishonest Alice, who infers basis C but destroys |C{+-}> by setting R to be identical to S in the commitment phase. If a classical bit is coded in a block of mxn qubit particles, impartial examinations and probabilistic security criteria can be achieved.

Framed bit error rate testing for 100G ethernet equipment

DEFF Research Database (Denmark)

Rasmussen, Anders; Ruepp, Sarah Renée; Berger, Michael Stübert

2010-01-01

rate. As the need for 100 Gigabit Ethernet equipment rises, so does the need for equipment, which can properly test these systems during development, deployment and use. This paper presents early results from a work-in-progress academia-industry collaboration project and elaborates on the challenges...

Quantum bit string commitment protocol using polarization of mesoscopic coherent states

International Nuclear Information System (INIS)

Mendonca, Fabio Alencar; Ramos, Rubens Viana

2008-01-01

In this work, we propose a quantum bit string commitment protocol using polarization of mesoscopic coherent states. The protocol is described and its security against brute force and quantum cloning machine attack is analyzed

Quantum bit string commitment protocol using polarization of mesoscopic coherent states

Science.gov (United States)

Mendonça, Fábio Alencar; Ramos, Rubens Viana

2008-02-01

In this work, we propose a quantum bit string commitment protocol using polarization of mesoscopic coherent states. The protocol is described and its security against brute force and quantum cloning machine attack is analyzed.

Error statistics in a high-speed fibreoptic communication line with a phase shift of odd bits

International Nuclear Information System (INIS)

Shapiro, Elena G

2009-01-01

The propagation of optical pulses through a fibreoptic communication line with a phase shift of odd bits is directly numerically simulated. It is shown that simple analytic expressions approximate well the error probability. The phase shift of odd bits in the initial sequence is statistically shown to decrease significantly the error probability in the communication line. (fibreoptic communication lines)

Diamonds are forever : roller bits once ruled the roost, but PDC drillbits have emerged as oilpatch champions

Energy Technology Data Exchange (ETDEWEB)

Cope, G.

2008-06-15

Polycrystalline diamond compact (PDC) drill bits are used in over 60 per cent of wells currently being drilled. PDC bits use thumb-sized diamond-impregnated cutters fixed into the body of the bit in order to shear the rock. Certain rock formations that contain large amounts of chert or pyrite can destroy PDCs, which are ideally suited for use in offshore wells which have soft, homogenous rock sections. This article discussed recent research programs conducted to analyze the strengths and weaknesses of PDCs and improve their cutting efficiency through the analysis of cutter geometry, material composition, and processing conditions. Researchers have now discovered that diamond chips of 10 microns performed better than chips of 70 microns. Cutters were found to be more durable when cobalt was used as a binder to sinter the diamond chips. PDCs are now being used extensively by the oil sands industry due to their abrasion resistance. Research is ongoing in order to improve the performance of PDC drill bits. 2 figs.

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....

An Efficient Method for Image and Audio Steganography using Least Significant Bit (LSB) Substitution

Science.gov (United States)

Chadha, Ankit; Satam, Neha; Sood, Rakshak; Bade, Dattatray

2013-09-01

In order to improve the data hiding in all types of multimedia data formats such as image and audio and to make hidden message imperceptible, a novel method for steganography is introduced in this paper. It is based on Least Significant Bit (LSB) manipulation and inclusion of redundant noise as secret key in the message. This method is applied to data hiding in images. For data hiding in audio, Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) both are used. All the results displayed prove to be time-efficient and effective. Also the algorithm is tested for various numbers of bits. For those values of bits, Mean Square Error (MSE) and Peak-Signal-to-Noise-Ratio (PSNR) are calculated and plotted. Experimental results show that the stego-image is visually indistinguishable from the original cover-image when nsteganography process does not reveal presence of any hidden message, thus qualifying the criteria of imperceptible message.

Plain packaging and indirect expropriation of trademark rights under BITs: does FCTC help to establish a right to regulate tobacco products?

Science.gov (United States)

Lo, Chang-Fa

2012-12-01

Recently the giant tobacco company Philip Morris served its notice to launch an investor-to-state dispute settlement proceeding against the Australian Government for its introduction of plain packaging requirements on tobacco products. It is an important event in the field of intellectual property, investment and international health law. The fundamental questions involved are whether the restriction of trademark rights as a result of the plain packaging requirement is a compensable indirect expropriation under BITs or whether it falls within the scope of government's right to regulate and thus become not compensable. This paper is of the view that the requirement of plain packaging will deprive the essential value or core function of trademark rights and thus constitutes an indirect expropriation under BITs. However, such indirect expropriation meets the public interest requirement and the necessity requirement. The paper further argues that sovereign States have an inherent right to regulate domestic economic activities. Since the pain packaging requirements provided in the FCTC Guidelines are expected to protect the value of human lives and health, the protected values clearly outweigh the affected commercial interests of tobacco companies. Also the justification for host States to adopt a plain packaging policy is strong. Thus, the interpreters of BITs need to pay higher respect to the host State's sovereign power concerning its right to regulate tobacco products for a legitimate purpose. The conclusion of the paper is that the host States should enjoy a defense of the right to regulate to refuse compensation. The author believes that this is the only reasonable conclusion to avoid possible conflicts between different treaty systems (BITs and the FCTC) and between different legal systems and fields (trademark law, investment law and international health law).

Bit-Vector Search Filtering with Application to a Kanji Dictionary

DEFF Research Database (Denmark)

Skala, Matthew

2016-01-01

dimensionality in geometric problems also causes their query languages to become expressive and inefficient. The IDSgrep kanji dictionary software approaches a highly expressive tree-matching query problem with a filtering technique set in 128-bit Hamming space. It can be a model for other highly expressive...

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

Using an FPGA for Fast Bit Accurate SoC Simulation

NARCIS (Netherlands)

Wolkotte, P.T.; Holzenspies, P.K.F.; Smit, Gerardus Johannes Maria

In this paper we describe a sequential simulation method to simulate large parallel homo- and heterogeneous systems on a single FPGA. The method is applicable for parallel systems were lengthy cycle and bit accurate simulations are required. It is particularly designed for systems that do not fit

Design and Implementation of Decimation Filter for 13-bit Sigma-Delta ADC Based on FPGA

Directory of Open Access Journals (Sweden)

Khalid Khaleel Mohammed

2016-10-01

Full Text Available A 13 bit Sigma-Delta ADC for a signal band of 40K Hz is designed in MATLAB Simulink and then implemented using Xilinx system generator tool.  The first order Sigma-Delta modulator is designed to work at a signal band of 40 KHz at an oversampling ratio (OSR of 256 with a sampling frequency of 20.48 MHz. The proposed decimation filter design is consists of a second order Cascaded Integrator Comb filter (CIC followed by two finite impulse response (FIR filters. This architecture reduces the need for multiplication which is need very large area. This architecture implements a decimation ratio of 256 and allows a maximum resolution of 13  bits in the output of the filter. The decimation filter was designed  and  tested  in  Xilinx  system  generator  tool  which  reduces  the  design  cycle  by  directly generating efficient VHDL code. The results obtained show that the overall Sigma-Delta ADC is able to achieve an ENOB (Effective Number Of Bit of 13.71 bits and SNR of 84.3 dB

Offset correction system for 128-channel self-triggering readout chip with in-channel 5-bit energy measurement functionality

Energy Technology Data Exchange (ETDEWEB)

Otfinowski, P., E-mail: potfin@agh.edu.pl; Grybos, P.; Szczygiel, R.; Kasinski, K.

2015-04-21

We report on a novel, two-stage 8-bit trimming solution dedicated for multichannel systems with reduced trim DAC area occupancy. The presented design was used for comparator offset correction in a 128-channel particle tracking, self-triggering readout system and manufactured in 180 nm CMOS process. The 8-bit trim DAC has a range of ±165 mV, current consumption of 3.2 µA and occupies an area of 37 µm×17 µm in each channel, which corresponds to a 6-bit conventional current steering DAC with similar linearity.

A High Resolution Switched Capacitor 1bit Sigma-Delta Modulator for Low-Voltage/Low-Power Applications

DEFF Research Database (Denmark)

Furst, Claus Efdmann

1996-01-01

A high resolution 1bit Sigma-Delta modulator for low power/low voltage applications is presented. The modulator operates at a supply of 1-1.5V, the current drain is 0.1mA. The maximum resolution is 87dB equivalent to 14 bits of resolution. This is achieved with a signal-band of 5kHz, over-samplin...

Feasibility study of current pulse induced 2-bit/4-state multilevel programming in phase-change memory

Science.gov (United States)

Liu, Yan; Fan, Xi; Chen, Houpeng; Wang, Yueqing; Liu, Bo; Song, Zhitang; Feng, Songlin

2017-08-01

In this brief, multilevel data storage for phase-change memory (PCM) has attracted more attention in the memory market to implement high capacity memory system and reduce cost-per-bit. In this work, we present a universal programing method of SET stair-case current pulse in PCM cells, which can exploit the optimum programing scheme to achieve 2-bit/ 4state resistance-level with equal logarithm interval. SET stair-case waveform can be optimized by TCAD real time simulation to realize multilevel data storage efficiently in an arbitrary phase change material. Experimental results from 1 k-bit PCM test-chip have validated the proposed multilevel programing scheme. This multilevel programming scheme has improved the information storage density, robustness of resistance-level, energy efficient and avoiding process complexity.

A higher chest compression rate may be necessary for metronome-guided cardiopulmonary resuscitation.

Science.gov (United States)

Chung, Tae Nyoung; Kim, Sun Wook; You, Je Sung; Cho, Young Soon; Chung, Sung Phil; Park, Incheol

2012-01-01

Metronome guidance is a simple and economical feedback system for guiding cardiopulmonary resuscitation (CPR). However, a recent study showed that metronome guidance reduced the depth of chest compression. The results of previous studies suggest that a higher chest compression rate is associated with a better CPR outcome as compared with a lower chest compression rate, irrespective of metronome use. Based on this finding, we hypothesized that a lower chest compression rate promotes a reduction in chest compression depth in the recent study rather than metronome use itself. One minute of chest compression-only CPR was performed following the metronome sound played at 1 of 4 different rates: 80, 100, 120, and 140 ticks/min. Average compression depths (ACDs) and duty cycles were compared using repeated measures analysis of variance, and the values in the absence and presence of metronome guidance were compared. Both the ACD and duty cycle increased when the metronome rate increased (P = .017, metronome rates of 80 and 100 ticks/min were significantly lower than those for the procedures without metronome guidance. The ACD and duty cyle for chest compression increase as the metronome rate increases during metronome-guided CPR. A higher rate of chest compression is necessary for metronome-guided CPR to prevent suboptimal quality of chest compression. Copyright © 2012 Elsevier Inc. All rights reserved.

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

A hybrid bit-encoding for SAT planning based on clique-partitioning

Science.gov (United States)

Tapia, Cristóbal; San Segundo, Pablo; Galán, Ramón

2017-09-01

Planning as satisfiability is one of the most efficient ways to solve classic automated planning problems. In SAT planning, the encoding used to convert the problem to a SAT formula is critical for the performance of the SAT solver. This paper presents a novel bit-encoding that reduces the number of bits required to represent actions in a SAT-based automated planning problem. To obtain such encoding we first build a conflict graph, which represents incompatibilities of pairs of actions, and bitwise encode the subsets of actions determined by a clique partition. This reduces the number of Boolean variables and clauses of the SAT encoding, while preserving the possibility of parallel execution of compatible (non-neighbor) actions. The article also describes an appropriate algorithm for selecting the clique partition for this application and compares the new encodings obtained over some standard planning problems.

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.)

NASA Glenn Steady-State Heat Pipe Code GLENHP: Compilation for 64- and 32-Bit Windows Platforms

Science.gov (United States)

Tower, Leonard K.; Geng, Steven M.

2016-01-01

A new version of the NASA Glenn Steady State Heat Pipe Code, designated "GLENHP," is introduced here. This represents an update to the disk operating system (DOS) version LERCHP reported in NASA/TM-2000-209807. The new code operates on 32- and 64-bit Windows-based platforms from within the 32-bit command prompt window. An additional evaporator boundary condition and other features are provided.

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 ...

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

X-band 5-bit MMIC phase shifter with GaN HEMT technology

Science.gov (United States)

Sun, Pengpeng; Liu, Hui; Zhang, Zongjing; Geng, Miao; Zhang, Rong; Luo, Weijun

2017-10-01

The design approach and performance of a 5-bit digital phase shifter implemented with 0.25 μm GaN HEMT technology for X-band phased arrays are described. The switched filter and high-pass/low-pass networks are proposed in this article. For all 32 states of the 5-bit phase shifter, the RMS phase error less than 5.5°, RMS amplitude error less than 0.8 dB, insertion loss less than 12 dB and input/output return loss less than 8.5 dB are obtained overall 8-12 GHz. The continuous wave power capability is also measured, and a typical input RF P1dB data of 32 dBm is achieved at 8 GHz.

Observational Evidence for Two Cosmological Predictions Made by Bit-String Physics; TOPICAL

International Nuclear Information System (INIS)

Noyes, H. Pierre

2001-01-01

A decade ago bit-string physics predicted that the baryon/photon ratio at the time of nucleogenesis(eta)= 1 1/256(sup 4) and that the dark matter/baryonic matter ratio(Omega)(sub DM)/(Omega)(sub B)= 12.7. Accepting that the normalized Hubble constant is constrained observationally to lie in the range 0.6 and lt; h(sub 0) and lt; 0.8, this translates into a prediction that 0.325 and gt;(Omega)(sub M) and gt; 0.183. This and a prediction by E.D. Jones, using a model-independent argument and ideas with which bit-string physics is not inconsistent, that the cosmological constant(Omega)(sub(Lambda))= 0.6(+-) 0.1 are in reasonable agreement with recent cosmological observations, including the BOOMERANG data

Programming 16-Bit PIC Microcontrollers in C Learning to Fly the PIC 24

CERN Document Server

Di Jasio, Lucio

2011-01-01

New in the second edition: * MPLAB X support and MPLAB C for the PIC24F v3 and later libraries * I2C™ interface * 100% assembly free solutions * Improved video, PAL/NTSC * Improved audio, RIFF files decoding * PIC24F GA1, GA2, GB1 and GB2 support   Most readers will associate Microchip's name with the ubiquitous 8-bit PIC microcontrollers but it is the new 16-bit PIC24F family that is truly stealing the scene. Orders of magnitude increases of performance, memory size and the rich peripheral set make programming these devices in C a must. This new guide by Microchip insid

Flexible Multi-Bit Feedback Design for HARQ Operation of Large-Size Data Packets in 5G

DEFF Research Database (Denmark)

Khosravirad, Saeed; Mudolo, Luke; Pedersen, Klaus I.

2017-01-01

large-size data packet thanks to which the transmitter node can reduce the retransmission size to only include the initially failed segments of the packet. We study the effect of feedback size on retransmission efficiency through extensive link-level simulations over realistic channel models. Numerical......A reliable feedback channel is vital to report decoding acknowledgments in retransmission mechanisms such as the hybrid automatic repeat request (HARQ). While the feedback bits are known to be costly for the wireless link, a feedback message more informative than the conventional single......-bit feedback can increase resource utilization efficiency. Considering the practical limitations for increasing feedback message size, this paper proposes a framework for the design of flexible-content multi-bit feedback. The proposed design is capable of efficiently indicating the faulty segments of a failed...

Bergy Bit and Melt Water Trajectories in Godthåbsfjord (SW Greenland) Observed by the Expendable Ice Tracker

NARCIS (Netherlands)

Carlson, D.F.; Boone, W.; Meire, L.; Abermann, J.; Rysgaard, S.

2017-01-01

Icebergs and bergy bits makes up a significant component of the total freshwater flux from the Greenland Ice Sheet to the ocean. Observations of iceberg trajectories are biased toward larger icebergs and, as a result, the drift characteristics of smaller icebergs and bergy bits are poorly

Front-end data processing using the bit-sliced microprocessor

International Nuclear Information System (INIS)

Machen, D.R.

1979-01-01

A state-of-the-art computing device, based upon the high-speed bit-sliced microprocessor, was developed into hardware for front-end data processing in both control and experiment applications at the Los Alamos Scientific Laboratory. The CAMAC Instrumentation Standard provides the framework for the high-speed hardware, allowing data acquisition and processing to take place at the data source in a CAMAC crate. 5 figures

Design of a low power 10 bit 300 ksps multi-channel SAR ADC for wireless sensor network applications

International Nuclear Information System (INIS)

Hong Hui; Li Shiliang; Zhou Tao

2015-01-01

This paper presents a low power 10 bit 300 ksps successive approximation register analog-to-digital converter (SAR ADC) which is applied in wireless sensor network (WSN) applications. A single ended energy-saving split capacitor DAC array and a latch comparator with a rail to rail input stage are utilized to implement the ADC, which can reduce power dissipation while expanding the full scale input range and improve the signal-to-noise ratio (SNR). For power optimization the supply voltage of the SAR ADC is designed to be as low as 2 V. Four analog input channels are designed which make the ADC more suitable for WSN applications. The prototype circuit is fabricated using 3.3 V, 0.35 μm 2P4M CMOS technology and occupies an active chip area of 1.23 mm 2 . The test results show that the power dissipation is only 200 μW at a 2 V power supply and a sampling rate of 166 ksps. The calculated SNR is 58.25 dB, the ENOB is 9.38 bit and the FOM is 4.95 pJ/conversion-step. (paper)

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

High speed and adaptable error correction for megabit/s rate quantum key distribution.

Science.gov (United States)

Dixon, A R; Sato, H

2014-12-02

Quantum Key Distribution is moving from its theoretical foundation of unconditional security to rapidly approaching real world installations. A significant part of this move is the orders of magnitude increases in the rate at which secure key bits are distributed. However, these advances have mostly been confined to the physical hardware stage of QKD, with software post-processing often being unable to support the high raw bit rates. In a complete implementation this leads to a bottleneck limiting the final secure key rate of the system unnecessarily. Here we report details of equally high rate error correction which is further adaptable to maximise the secure key rate under a range of different operating conditions. The error correction is implemented both in CPU and GPU using a bi-directional LDPC approach and can provide 90-94% of the ideal secure key rate over all fibre distances from 0-80 km.

Linear-Time Non-Malleable Codes in the Bit-Wise Independent Tampering Model

DEFF Research Database (Denmark)

Cramer, Ronald; Damgård, Ivan Bjerre; Döttling, Nico

Non-malleable codes were introduced by Dziembowski et al. (ICS 2010) as coding schemes that protect a message against tampering attacks. Roughly speaking, a code is non-malleable if decoding an adversarially tampered encoding of a message m produces the original message m or a value m' (eventuall...... non-malleable codes of Agrawal et al. (TCC 2015) and of Cher- aghchi and Guruswami (TCC 2014) and improves the previous result in the bit-wise tampering model: it builds the first non-malleable codes with linear-time complexity and optimal-rate (i.e. rate 1 - o(1)).......Non-malleable codes were introduced by Dziembowski et al. (ICS 2010) as coding schemes that protect a message against tampering attacks. Roughly speaking, a code is non-malleable if decoding an adversarially tampered encoding of a message m produces the original message m or a value m' (eventually...... abort) completely unrelated with m. It is known that non-malleability is possible only for restricted classes of tampering functions. Since their introduction, a long line of works has established feasibility results of non-malleable codes against different families of tampering functions. However...

AES Encryption Algorithm Optimization Based on 64-bit Processor Android Platform

Directory of Open Access Journals (Sweden)

ZHAO Jun

2017-06-01

Full Text Available Algorithm implemented on the mobile phone is different from one on PC． It requires little storage space and low power consumption． Standard AES S-box design uses look up table，and has high complexity and high power consumption，so it needs to be optimized when used in mobile phones． In our optimization AES encryption algorithm，the packet length is expanded to 256 bits，which would increase the security of our algorithm; look up table is replaced by adding the affine transformation based on inversion，which would reduce the storage space; operation is changed into 16-bit input and 64-bit output by merging the three steps，namely SubWords，ShiftＲows MixColumns and AddＲoundKey，which would improve the operation efficiency of the algorithm． The experimental results show that our algorithm not only can greatly enhance the encryption strength，but also maintain high computing efficiency．

Low dose rate gamma ray induced loss and data error rate of multimode silica fibre links

International Nuclear Information System (INIS)

Breuze, G.; Fanet, H.; Serre, J.

1993-01-01

Fiber optics data transmission from numerous multiplexed sensors, is potentially attractive for nuclear plant applications. Multimode silica fiber behaviour during steady state gamma ray exposure is studied as a joint programme between LETI CE/SACLAY and EDF Renardieres: transmitted optical power and bit error rate have been measured on a 100 m optical fiber

Complex networks generated by the Penna bit-string model: Emergence of small-world and assortative mixing

Science.gov (United States)

Li, Chunguang; Maini, Philip K.

2005-10-01

The Penna bit-string model successfully encompasses many phenomena of population evolution, including inheritance, mutation, evolution, and aging. If we consider social interactions among individuals in the Penna model, the population will form a complex network. In this paper, we first modify the Verhulst factor to control only the birth rate, and introduce activity-based preferential reproduction of offspring in the Penna model. The social interactions among individuals are generated by both inheritance and activity-based preferential increase. Then we study the properties of the complex network generated by the modified Penna model. We find that the resulting complex network has a small-world effect and the assortative mixing property.

The new designs of diamond drill bits for composite polymers tooling

Directory of Open Access Journals (Sweden)

Ruslan Yu. Melentiev

2015-12-01

Full Text Available The author explores the drilling operation of some new engineering materials such as carbon fiber reinforced plastics (CFRP and other polymers that have an anisotropic structure, high-strength and elastic properties combined with low heat endurance. Such combination of properties makes impossible the simple transfer of the existing technologies for classic materials working to considered new class. At the same time, the existing tools cannot assure the specified quality of tooled products at the current productivity and tool life. Aim: The aim of this research is to increase the process efficiency of diamond drilling in composite polymers by developing the new designs of diamond drill bits. Materials and Methods: One of the most promising directions to solve this problem is the diamond coated abrasive type tool. This paper addresses and classifies the existing types of diamond drill bits according to their application and operation. The literature data analysis of known disadvantages during drilling operation, the quality of surface and joining face was performed. Results: The experimental researches of the author prove the negative meaning of the already known but kept out fact – the drill core blocking. The most important factors and structural features affecting the CFRP drilling process are revealed. The accounting of these factors allowed creating the set of unique designs of diamond drill bits for different purposes. The presented patented models has different allowance distribution schemes and cutting forces, thus satisfy the mechanical requirements of quality, productivity, tool life and hole geometry in the tooling of the specified material class.

A 100 MS/s 9 bit 0.43 mW SAR ADC with custom capacitor array

Science.gov (United States)

Jingjing, Wang; Zemin, Feng; Rongjin, Xu; Chixiao, Chen; Fan, Ye; Jun, Xu; Junyan, Ren

2016-05-01

A low power 9 bit 100 MS/s successive approximation register analog-to-digital converter (SAR ADC) with custom capacitor array is presented. A brand-new 3-D MOM unit capacitor is used as the basic capacitor cell of this capacitor array. The unit capacitor has a capacitance of 1 fF. Besides, the advanced capacitor array structure and switch mode decrease the power consumption a lot. To verify the effectiveness of this low power design, the 9 bit 100 MS/s SAR ADC is implemented in TSMC IP9M 65 nm LP CMOS technology. The measurement results demonstrate that this design achieves an effective number of bits (ENOB) of 7.4 bit, a signal-to-noise plus distortion ratio (SNDR) of 46.40 dB and a spurious-free dynamic range (SFDR) of 62.31 dB at 100 MS/s with 1 MHz input. The SAR ADC core occupies an area of 0.030 mm2 and consumes 0.43 mW under a supply voltage of 1.2 V. The figure of merit (FOM) of the SAR ADC achieves 23.75 fJ/conv. Project supported by the National High-Tech Research and Development Program of China (No. 2013AA014101).

PENINGKATAN KINERJA PERANGKAT ELEKTRONIK BERBASIS MIKROKONTROLER AVR 8 BIT DENGAN MENGGUNAKAN RTOS (REAL TIME OPERATING SYSTEM

Directory of Open Access Journals (Sweden)

I Wayan Sutaya

2015-01-01

Full Text Available Tujuan dari penelitian ini adalah untuk mengimplementasikan RTOS (Real Time Operating System pada perangkat elektronik berbasis mikrokontroler AVR 8 bit sehingga didapatkan peningkatan kinerja pada perangkat tersebut. RTOS yang digunakan adalah freeRTOS dimana RTOS ini mendukung mikrokontroler 8 bit, berukuran kecil, dan bersifat open source. Hasil penelitian ini berguna bagi praktisi-praktisi elektronika dalam hal menekan biaya produksi pembuatan perangkat elektronik berbasis mikrokontroler 8 bit karena resource yang digunakan bisa dikurangi. Metode yang digunakan adalah metode penelitian pengembangan (Research and development dengan cara membuat studi kasus perangkat elektronik yang berbasis mikrokontroler. Perangkat elektronik yang dibuat adalah unit kendali elektronik pada sepeda motor. Selanjutnya mikrokontroler pada perangkat ini diprogram dengan menggunakan dua skenario. Skenario pertama adalah tanpa menggunakan RTOS dan skenario kedua dengan menggunakan RTOS. Dari dua skenario ini dilakukan pengujian dan analisis untuk mengetahui besar peningkatan kinerja yang didapat.

3.56-bits/cm Compact Inkjet Printed and Application Specific Chipless RFID Tag

KAUST Repository

Khan, Munawar M.

2015-10-26

© 2002-2011 IEEE. In this letter, a 28.5-bit chipless RFID tag, based on paper substrate and realized using inkjet printing technique is presented. Operating within ultrawideband, the tag occupies a compact size of 2 × 4 cm2. Focusing on applications requiring time and date identification, a novel encoding technique is presented that allows efficient frequency band allocation based on the number of required instances of time and date variables. A figure of merit (FOM) relating coding capacity and tag dimensions coined as code density is also introduced. A systematic design process followed by simulations and verified through measurements reveal a high code density of 3.56 bits/cm2 for the presented chipless tag.

Increase in Multicast OFDM Data Rate in PLC Network using Adaptive LP-OFDM

OpenAIRE

Maiga , Ali; Baudais , Jean-Yves; Hélard , Jean-François

2009-01-01

ISBN: 978-1-4244-3523-4; International audience; Linear precoding (LP) technique applied to OFDM systems has already proved its ability to significantly increase the system throughput in a powerline communication (PLC) context. In this paper, we propose resource allocation algorithms based on the LP technique to increase the multicast OFDM systems bit rate. The conventional multicast capacity is limited by the user which experiences the worst channel conditions. To increase the multicast bit ...

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

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...

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)

Assessing the efficiency of carbide drill bits and factors influencing their application to debris-rich subglacial ice

Science.gov (United States)

Yang, Cheng; Jiang, Jianliang; Cao, Pinlu; Wang, Jinsong; Fan, Xiaopeng; Shang, Yuequan; Talalay, Pavel

2017-09-01

When drilling into subglacial bedrock, drill operators commonly encounter basal ice containing high concentrations of rock debris and melt water. As such conditions can easily damage conventional ice drills, researchers have experimented with carbide, diamond, and polycrystalline diamond compact drill bits, with varying degrees of success. In this study, we analyzed the relationship between drilling speed and power consumption for a carbide drill bit penetrating debris-rich ice. We also assessed drill load, rotation speed, and various performance parameters for the cutting element, as well as the physical and mechanical properties of rock and ice, to construct mathematical models. We show that our modeled results are in close agreement with the experimental data, and that both penetration speed and power consumption are positively correlated with drill speed and load. When used in ice with 30% rock content, the maximum penetration speed of the carbide bit is 3.4 mm/s with a power consumption of ≤0.5 kW, making the bit suitable for use with existing electromechanical drills. Our study also provides a guide for further research into cutting heat and equipment design.

An Asynchronous Circuit Design Technique for a Flexible 8-Bit Microprocessor

Science.gov (United States)

Karaki, Nobuo; Nanmoto, Takashi; Inoue, Satoshi

This paper presents an asynchronous design technique, an enabler for the emerging technology of flexible microelectronics that feature low-temperature processed polysilicon (LTPS) thin-film transistors (TFT) and surface-free technology by laser annealing/ablation (SUFTLA®). The first design instance chosen is an 8-bit microprocessor. LTPS TFTs are good for realizing displays having integrated VLSI circuit at lower costs. However, LTPS TFTs have drawbacks, including substantial deviations in characteristics and the self-heating phenomenon. To solve these problems, the authors adopted the asynchronous circuit design technique and developed an asynchronous design language called Verilog+, which is based on a subset of Verilog HDL® and includes minimal primitives used for describing the communications between modules, and the dedicated tools including a translator called xlator and a synthesizer called ctrlsyn. The flexible 8-bit microprocessor stably operates at 500kHz, drawing 180μA from a 5V power source. The microprocessor's electromagnetic emissions are 21dB less than those of the synchronous counterpart.

Improved method of generating bit reversed numbers for calculating fast fourier transform

Digital Repository Service at National Institute of Oceanography (India)

Suresh, T.

Fast Fourier Transform (FFT) is an important tool required for signal processing in defence applications. This paper reports an improved method for generating bit reversed numbers needed in calculating FFT using radix-2. The refined algorithm takes...

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)

Cheat-sensitive commitment of a classical bit coded in a block of m × n round-trip qubits

Science.gov (United States)

Shimizu, Kaoru; Fukasaka, Hiroyuki; Tamaki, Kiyoshi; Imoto, Nobuyuki

2011-08-01

This paper proposes a quantum protocol for a cheat-sensitive commitment of a classical bit. Alice, the receiver of the bit, can examine dishonest Bob, who changes or postpones his choice. Bob, the sender of the bit, can examine dishonest Alice, who violates concealment. For each round-trip case, Alice sends one of two spin states |S±⟩ by choosing basis S at random from two conjugate bases X and Y. Bob chooses basis C ∈ {X,Y} to perform a measurement and returns a resultant state |C±⟩. Alice then performs a measurement with the other basis R (≠S) and obtains an outcome |R±⟩. In the opening phase, she can discover dishonest Bob, who unveils a wrong basis with a faked spin state, or Bob can discover dishonest Alice, who infers basis C but destroys |C±⟩ by setting R to be identical to S in the commitment phase. If a classical bit is coded in a block of m × n qubit particles, impartial examinations and probabilistic security criteria can be achieved.

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

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...

Higher education and the labour market : international policy frameworks for regulating graduate employability

NARCIS (Netherlands)

Kottmann, Andrea; de Weert, Egbert

2013-01-01

This report “Higher Education and the Labour Market” builds upon the previous report and aims to digging a bit deeper into some themes in the countries Belgium, Denmark, England, Finland, Germany, Sweden and the United States, and update developments since the first review in 2011. The following

10–25 GHz frequency reconfigurable MEMS 5-bit phase shifter using push–pull actuator based toggle mechanism

International Nuclear Information System (INIS)

Dey, Sukomal; Koul, Shiban K

2015-01-01

This paper presents a frequency tunable 5-bit true-time-delay digital phase shifter using radio frequency microelectromechanical system (RF MEMS) technology. The phase shifter is based on the distributed MEMS transmission line (DMTL) concept utilizing a MEMS varactor. The main source of frequency tuning in this work is a bridge actuation mechanism followed by capacitance variation. Two stages of actuation mechanisms (push and pull) are used to achieve a 2:1 tuning ratio. Accurate control of the actuation voltage between the pull to push stages contributes differential phase shift over the band of interest. The functional behavior of the push–pull actuation over the phase shifter application is theoretically established, experimentally investigated and validated with simulation. The phase shifter is fabricated monolithically using a gold based surface micromachining process on an alumina substrate. The individual primary phase-bits (11.25°/22.5°/45°/90°/180°) that are the fundamental building blocks of the complete 5-bit phase shifter are designed, fabricated and experimentally characterized from 10–25 GHz for specific applications. Finally, the complete 5-bit phase shifter demonstrates an average phase error of 4.32°, 2.8°, 1° and 1.58°, an average insertion loss of 3.76, 4.1, 4.2 and 4.84 dB and an average return loss of 11.7, 12, 14 and 11.8 dB at 10, 12, 17.2 and 25 GHz, respectively. To the best of the authors’ knowledge, this is the first reported band tunable stand alone 5-bit phase shifter in the literature which can work over the large spectrum for different applications. The total area of the 5-bit phase shifter is 15.6 mm 2 . Furthermore, the cold-switched reliability of the unit cell and the complete 5-bit MEMS phase shifter are extensively investigated and presented. (paper)

A Low-Power Single-Bit Continuous-Time ΔΣ Converter with 92.5 dB Dynamic Range for Biomedical Applications

Directory of Open Access Journals (Sweden)

Vishal Saxena

2012-07-01

Full Text Available A third-order single-bit CT-ΔΣ modulator for generic biomedical applications is implemented in a 0.15 µm FDSOI CMOS process. The overall power efficiency is attained by employing a single-bit ΔΣ and a subthreshold FDSOI process. The loop-filter coefficients are determined using a systematic design centering approach by accounting for the integrator non-idealities. The single-bit CT-ΔΣ modulator consumes 110 µW power from a 1.5 V power supply when clocked at 6.144 MHz. The simulation results for the modulator exhibit a dynamic range of 94.4 dB and peak SNDR of 92.4 dB for 6 kHz signal bandwidth. The figure of merit (FoM for the third-order, single-bit CT-ΔΣ modulator is 0.271 pJ/level.

Rate-distortion analysis of steganography for conveying stereovision disparity maps

Science.gov (United States)

Umeda, Toshiyuki; Batolomeu, Ana B. D. T.; Francob, Filipe A. L.; Delannay, Damien; Macq, Benoit M. M.

2004-06-01

3-D images transmission in a way which is compliant with traditional 2-D representations can be done through the embedding of disparity maps within the 2-D signal. This approach enables the transmission of stereoscopic video sequences or images on traditional analogue TV channels (PAL or NTSC) or printed photographic images. The aim of this work is to study the achievable performances of such a technique. The embedding of disparity maps has to be seen as a global rate-distortion problem. The embedding capacity through steganography is determined by the transmission channel noise and by the bearable distortion on the watermarked image. The distortion of the 3-D image displayed as two stereo views depends on the rate allocated to the complementary information required to build those two views from one reference 2-D image. Results from the works on the scalar Costa scheme are used to optimize the embedding of the disparity map compressed bit stream into the reference image. A method for computing the optimal trade off between the disparity map distortion and embedding distortion as a function of the channel impairments is proposed. The goal is to get a similar distortion on the left (the reference image) and the right (the disparity compensated image) images. We show that in typical situations the embedding of 2 bits/pixels in the left image, while the disparity map is compressed at 1 bit per pixel leads to a good trade-off. The disparity map is encoded with a strong error correcting code, including synchronisation bits.

Strain rate effects in nuclear steels at room and higher temperatures

Energy Technology Data Exchange (ETDEWEB)

Solomos, G. E-mail: george.solomos@jrc.it; Albertini, C.; Labibes, K.; Pizzinato, V.; Viaccoz, B

2004-04-01

An investigation of strain rate, temperature and size effects in three nuclear steels has been conducted. The materials are: ferritic steel 20MnMoNi55 (vessel head), austenitic steel X6CrNiNb1810 (upper internal structure), and ferritic steel 26NiCrMo146 (bolting). Smooth cylindrical tensile specimens of three sizes have been tested at strain rates from 0.001 to 300 s{sup -1}, at room and elevated temperatures (400-600 deg. C). Full stress-strain diagrams have been obtained, and additional parameters have been calculated based on them. The results demonstrate a clear influence of temperature, which amounts into reducing substantially mechanical strengths with respect to RT conditions. The effect of strain rate is also shown. It is observed that at RT the strain rate effect causes up shifting of the flow stress curves, whereas at the higher temperatures a mild downshifting of the flow curves is manifested. Size effect tendencies have also been observed. Some implications when assessing the pressure vessel structural integrity under severe accident conditions are considered.

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

An electrically reprogrammable 1024 bits MNOS ROM using MNOS-SOS e/d technology

International Nuclear Information System (INIS)

Mackowiak, E.; Le Goascoz, V.

1976-01-01

A 1024 bits fully decoded electrically writable and erasable non volatile ROM is described. Memory cells and peripheral circuits are made using P channel silicon on sapphire enhancement depletion technology [fr

Quantum data locking for high-rate private communication

OpenAIRE

Lupo, Cosmo; Lloyd, Seth

2015-01-01

We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security ...

Why do younger women have higher breast cancer recurrence rates after breast-conserving surgery?

International Nuclear Information System (INIS)

Nishimura, Reiki; Matsuda, Masakazu; Miyayama, Haruhiko; Okazaki, Shinji; Kai, Chiharu; Ozaki, N.

2003-01-01

Preventing breast cancer recurrence after breast-conserving surgery is an important issue. The main factors contributing to such recurrence are positive margins, absence of radiotherapy and young age. To investigate the clinical significance of age in breast-conserving surgery, we examined the relationship between clinicopathological findings or outcome and age, especially young age. The cases were divided into three groups by age; 35 years old or less, 36-50y.o. and 51y.o. or higher. Between April 1989 and March 2003, 743 patients were treated with breast-conserving surgery. There were 49 patients aged 35 years old or less (6.6%). Younger age significantly correlated with positive surgical margin, lymph node metastases, higher proliferative activity, negative estrogen receptor (ER) or progesterone receptor (PgR), larger tumor size, and shorter nipple-tumor distances. Although younger patients had a higher recurrence rate irrespective of radiotherapy, margin status had an impact on recurrence rate. Thus, the reason young age was a significant factor for breast recurrence after breast-conserving surgery was that young patients frequently had numerous risk factors such as positive margin, higher proliferative activity, positive nodes, negative ER/PgR and larger tumor. However, negative surgical margins could reduce recurrence rates even in young women. These results suggest that more suitable criteria and strategies may be needed for young patients with breast cancer. (author)

Protons and heavy ions induced stuck bits on large capacity RAMs

Energy Technology Data Exchange (ETDEWEB)

Duzellier, S; Falguere, D; Ecoffet, R [Centre National d` Etudes Spatiales (CNES), 31 - Toulouse (France)

1994-12-31

A semi-permanent imprint effect has been observed, on large capacity memories (static and dynamic), during heavy ion and proton irradiations. The experimental circumstances of stuck bits occurrence are described and the influence of irradiation conditions discussed. A total dose testing complete the investigation. (author). 10 refs., 5 figs., 3 tabs.

A 10-bit 120-MS/s pipelined ADC with improved switch and layout scaling strategy

International Nuclear Information System (INIS)

Zhou Jia; Xu Lili; Li Fule; Wang Zhihua

2015-01-01

A 10 bit, 120 MS/s two-channel pipelined analog-to digital converter (ADC) is presented. The ADC is featured with improved switch by using the body effect to improve its conduction performance. A scaling down strategy is proposed to get more efficiency in the OTAs layout design. Implemented in a 0.18-μm CMOS technology, the ADC's prototype occupied an area of 2.05 × 1.83 mm 2 . With a sampling rate of 120-MS/s and an input of 4.9 MHz, the ADC achieves a spurious-free-dynamic range of 74.32 dB and signal-to-noise-and-distortion ratio of 55.34 dB, while consuming 220-mW/channel at 3-V supply. (paper)

Will ageing lead to a higher real exchange rate for the Netherlands?

NARCIS (Netherlands)

van Ewijk, C.; Volkerink, M.

2012-01-01

Long term projections for the Netherlands indicate that demand for nontradables—e.g. health care services—will increase relative to supply due to population ageing. If this leads to higher future real exchanges rates this will erode the return of the savings currently made to prepare for ageing.

Will ageing lead to a higher real exchange rate for the Netherlands?

NARCIS (Netherlands)

van Ewijk, C.; Volkerink, M.

2011-01-01

Long-term projections for the Netherlands indicate that demand for nontradables - e.g. health care services - will increase relative to supply due to population ageing. If this leads to higher future real exchanges rates this will erode the return of the savings currently made to prepare for ageing.

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...

Multi-bits error detection and fast recovery in RISC cores

International Nuclear Information System (INIS)

Wang Jing; Yang Xing; Zhang Weigong; Shen Jiao; Qiu Keni; Zhao Yuanfu

2015-01-01

The particles-induced soft errors are a major threat to the reliability of microprocessors. Even worse, multi-bits upsets (MBUs) are ever-increased due to the rapidly shrinking feature size of the IC on a chip. Several architecture-level mechanisms have been proposed to protect microprocessors from soft errors, such as dual and triple modular redundancies (DMR and TMR). However, most of them are inefficient to combat the growing multi-bits errors or cannot well balance the critical paths delay, area and power penalty. This paper proposes a novel architecture, self-recovery dual-pipeline (SRDP), to effectively provide soft error detection and recovery with low cost for general RISC structures. We focus on the following three aspects. First, an advanced DMR pipeline is devised to detect soft error, especially MBU. Second, SEU/MBU errors can be located by enhancing self-checking logic into pipelines stage registers. Third, a recovery scheme is proposed with a recovery cost of 1 or 5 clock cycles. Our evaluation of a prototype implementation exhibits that the SRDP can successfully detect particle-induced soft errors up to 100% and recovery is nearly 95%, the other 5% will inter a specific trap. (paper)

Multi-bits error detection and fast recovery in RISC cores

Science.gov (United States)

Jing, Wang; Xing, Yang; Yuanfu, Zhao; Weigong, Zhang; Jiao, Shen; Keni, Qiu

2015-11-01

The particles-induced soft errors are a major threat to the reliability of microprocessors. Even worse, multi-bits upsets (MBUs) are ever-increased due to the rapidly shrinking feature size of the IC on a chip. Several architecture-level mechanisms have been proposed to protect microprocessors from soft errors, such as dual and triple modular redundancies (DMR and TMR). However, most of them are inefficient to combat the growing multi-bits errors or cannot well balance the critical paths delay, area and power penalty. This paper proposes a novel architecture, self-recovery dual-pipeline (SRDP), to effectively provide soft error detection and recovery with low cost for general RISC structures. We focus on the following three aspects. First, an advanced DMR pipeline is devised to detect soft error, especially MBU. Second, SEU/MBU errors can be located by enhancing self-checking logic into pipelines stage registers. Third, a recovery scheme is proposed with a recovery cost of 1 or 5 clock cycles. Our evaluation of a prototype implementation exhibits that the SRDP can successfully detect particle-induced soft errors up to 100% and recovery is nearly 95%, the other 5% will inter a specific trap.

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.

Extending R packages to support 64-bit compiled code: An illustration with spam64 and GIMMS NDVI3g data

Science.gov (United States)

Gerber, Florian; Mösinger, Kaspar; Furrer, Reinhard

2017-07-01

Software packages for spatial data often implement a hybrid approach of interpreted and compiled programming languages. The compiled parts are usually written in C, C++, or Fortran, and are efficient in terms of computational speed and memory usage. Conversely, the interpreted part serves as a convenient user-interface and calls the compiled code for computationally demanding operations. The price paid for the user friendliness of the interpreted component is-besides performance-the limited access to low level and optimized code. An example of such a restriction is the 64-bit vector support of the widely used statistical language R. On the R side, users do not need to change existing code and may not even notice the extension. On the other hand, interfacing 64-bit compiled code efficiently is challenging. Since many R packages for spatial data could benefit from 64-bit vectors, we investigate strategies to efficiently pass 64-bit vectors to compiled languages. More precisely, we show how to simply extend existing R packages using the foreign function interface to seamlessly support 64-bit vectors. This extension is shown with the sparse matrix algebra R package spam. The new capabilities are illustrated with an example of GIMMS NDVI3g data featuring a parametric modeling approach for a non-stationary covariance matrix.

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.

A heterogeneous computing environment to solve the 768-bit RSA challenge

OpenAIRE

Kleinjung, Thorsten; Bos, Joppe Willem; Lenstra, Arjen K.; Osvik, Dag Arne; Aoki, Kazumaro; Contini, Scott; Franke, Jens; Thomé, Emmanuel; Jermini, Pascal; Thiémard, Michela; Leyland, Paul; Montgomery, Peter L.; Timofeev, Andrey; Stockinger, Heinz

2010-01-01

In December 2009 the 768-bit, 232-digit number RSA-768 was factored using the number field sieve. Overall, the computational challenge would take more than 1700 years on a single, standard core. In the article we present the heterogeneous computing approach, involving different compute clusters and Grid computing environments, used to solve this problem.

Experimental demonstration of real-time adaptively modulated DDO-OFDM systems with a high spectral efficiency up to 5.76bit/s/Hz transmission over SMF links.

Science.gov (United States)

Chen, Ming; He, Jing; Tang, Jin; Wu, Xian; Chen, Lin

2014-07-28

In this paper, a FPGAs-based real-time adaptively modulated 256/64/16QAM-encoded base-band OFDM transceiver with a high spectral efficiency up to 5.76bit/s/Hz is successfully developed, and experimentally demonstrated in a simple intensity-modulated direct-detection optical communication system. Experimental results show that it is feasible to transmit a raw signal bit rate of 7.19Gbps adaptively modulated real-time optical OFDM signal over 20km and 50km single mode fibers (SMFs). The performance comparison between real-time and off-line digital signal processing is performed, and the results show that there is a negligible power penalty. In addition, to obtain the best transmission performance, direct-current (DC) bias voltage for MZM and launch power into optical fiber links are explored in the real-time optical OFDM systems.

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

metaBIT, an integrative and automated metagenomic pipeline for analysing microbial profiles from high-throughput sequencing shotgun data

DEFF Research Database (Denmark)

Louvel, Guillaume; Der Sarkissian, Clio; Hanghøj, Kristian Ebbesen

2016-01-01

-throughput DNA sequencing (HTS). Here, we develop metaBIT, an open-source computational pipeline automatizing routine microbial profiling of shotgun HTS data. Customizable by the user at different stringency levels, it performs robust taxonomy-based assignment and relative abundance calculation of microbial taxa......, as well as cross-sample statistical analyses of microbial diversity distributions. We demonstrate the versatility of metaBIT within a range of published HTS data sets sampled from the environment (soil and seawater) and the human body (skin and gut), but also from archaeological specimens. We present......-friendly profiling of the microbial DNA present in HTS shotgun data sets. The applications of metaBIT are vast, from monitoring of laboratory errors and contaminations, to the reconstruction of past and present microbiota, and the detection of candidate species, including pathogens....

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.

Design and characterization of a 12-bit 10MS/s 10mW pipelined SAR ADC for CZT-based hard X-ray imager

Science.gov (United States)

Xue, F.; Gao, W.; Duan, Y.; Zheng, R.; Hu, Y.

2018-02-01

This paper presents a 12-bit pipelined successive approximation register (SAR) ADC for CZT-based hard X-ray Imager. The proposed ADC is comprised of a first-stage 6-bit SAR-based Multiplying Digital Analog Converter (MDAC) and a second-stage 8-bit SAR ADC. A novel MDAC architecture using Vcm-based Switching method is employed to maximize the energy efficiency and improve the linearity of the ADC. Moreover, the unit-capacitor array instead of the binary-weighted capacitor array is adopted to improve the conversion speed and linearity of the ADC in the first-stage MDAC. In addition, a new layout design method for the binary-weighted capacitor array is proposed to reduce the capacitor mismatches and make the routing become easier and less-time-consuming. Finally, several radiation-hardened-by-design technologies are adopted in the layout design against space radiation effects. The prototype chip was fabricated in 0.18 μm mixed-signal 1.8V/3.3V process and operated at 1.8 V supply. The chip occupies a core area of only 0.58 mm2. The proposed pipelined SAR ADC achieves a peak signal-to-noise-and-distortion ratio (SNDR) of 66.7 dB and a peak spurious-free dynamic range (SFDR) of 78.6 dB at 10 MS/s sampling rate and consumes 10 mW. The figure of merit (FOM) of the proposed ADC is 0.56 pJ/conversion-step.

International Drug Discovery Science and Technology--BIT's Seventh Annual Congress.

Science.gov (United States)

Bodovitz, Steven

2010-01-01

BIT's Seventh Annual International Drug Discovery Science and Technology Congress, held in Shanghai, included topics covering new therapeutic and technological developments in the field of drug discovery. This conference report highlights selected presentations on open-access approaches to R&D, novel and multifactorial targets, and technologies that assist drug discovery. Investigational drugs discussed include the anticancer agents astuprotimut-r (GlaxoSmithKline plc) and AS-1411 (Antisoma plc).

Influence du compartiment trophique dans les réponses des populations de poissons aux variations artificielles de débit

Directory of Open Access Journals (Sweden)

ORTH D. J.

1995-04-01

Full Text Available Les réponses des populations de poissons aux altérations de débit sont assez peu souvent correctement prédites à partir des simulations physiques d'habitat. Actuellement, les évaluations de débit réservé sont basées sur des analyses de l'habitat physique, qui sont supposées avoir une influence sur ces populations. Cela conduit au dilemme en matière de détermination de ces débits : combien d'espèces et de stades faut-il analyser et comment pondérer leur importance respective ? Dans certains cours d'eau, les simulations d'habitat physique issues de PHABSIM (Physical Habitat Simulation pour les poissons les plus courants montrent une surface pondérée utile insensible ou maximum à faible débit. Or, les débits moyens à forts débits sont indubitablement importants pour différentes raisons, telles que le recrutement des espèces inféodées à la plaine alluviale, le nettoyage du fond du lit, les entrées de matière organique et la production des invertébrés benthiques. La densité, la diversité et la production des insectes aquatiques dans différents types de cours d'eau montrent des variations spatiales et interannuelles considérables, souvent directement reliables aux débits. De même, la croissance et le succès de prise de nourriture des poissons varient en fonction de l'abondance des proies. Un modèle de chaîne trophique a été développé pour étudier l'influence de la nourriture de base (insectes aquatiques, proies constituées par les poissons de petite taille et écrevisses sur la production des poissons prédateurs clé (Black bass à petite bouche, Micropterus dolomieu, Rock bass, Ambloplites rupestris, et Poisson chat à tête plate, Pylodictis olivaris dans un grand cours d'eau à régime thermique chaud. L'analyse du modèle indique que la production des poissons est très dépendante de la disponibilité des proies, en particulier les insectes aquatiques et les écrevisses. A partir des analyses du mod

An improved chaotic cryptosystem based on circular bit shift and XOR operations

International Nuclear Information System (INIS)

Xu, Shu-Jiang; Chen, Xiu-Bo; Zhang, Ru; Yang, Yi-Xian; Guo, Yu-Cui

2012-01-01

A type of chaotic encryption scheme by combining circular bit shift with XOR operations was proposed in 2006 based on iterating chaotic maps. Soon after the proposal, it was cryptanalyzed and improved. Unfortunately, there are still two drawbacks in the two improved schemes. To strengthen the performance of the focused type of scheme, a new improved scheme based on Chen's chaotic system is proposed in this Letter. Simulation results and theoretical analysis show that our improved scheme is immune to information extracting by chosen plaintext attack and has expected cryptographic properties. -- Highlights: ► There are 2 drawbacks in 2 improved chaos-based encryption schemes by bit shift and XOR operation. ► FIPS 140-2 test show the random number sequence generated by CCS is statistical random. ► The plaintext is first permuted byte by byte, and then masked in the inverse order. ► Small perturbation based on output ciphertext is given to c of CCS after iterating it every time.

An improved chaotic cryptosystem based on circular bit shift and XOR operations

Energy Technology Data Exchange (ETDEWEB)

Xu, Shu-Jiang, E-mail: xushj@keylab.net [Information Security Center, Beijing University of Posts and Telecommunications, Beijing 100876 (China); State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences), Beijing 100049 (China); Shandong Provincial Key Laboratory of Computer Network, Shandong Computer Science Center, Jinan 250014 (China); Chen, Xiu-Bo [Information Security Center, Beijing University of Posts and Telecommunications, Beijing 100876 (China); State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences), Beijing 100049 (China); Zhang, Ru; Yang, Yi-Xian [Information Security Center, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Guo, Yu-Cui [School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

2012-02-20

A type of chaotic encryption scheme by combining circular bit shift with XOR operations was proposed in 2006 based on iterating chaotic maps. Soon after the proposal, it was cryptanalyzed and improved. Unfortunately, there are still two drawbacks in the two improved schemes. To strengthen the performance of the focused type of scheme, a new improved scheme based on Chen's chaotic system is proposed in this Letter. Simulation results and theoretical analysis show that our improved scheme is immune to information extracting by chosen plaintext attack and has expected cryptographic properties. -- Highlights: ► There are 2 drawbacks in 2 improved chaos-based encryption schemes by bit shift and XOR operation. ► FIPS 140-2 test show the random number sequence generated by CCS is statistical random. ► The plaintext is first permuted byte by byte, and then masked in the inverse order. ► Small perturbation based on output ciphertext is given to c of CCS after iterating it every time.

Increasing data distribution in BitTorrent networks by using network coding techniques

DEFF Research Database (Denmark)

Braun, Patrik János; Sipos, Marton A.; Ekler, Péter

2015-01-01

Abstract: Peer-to-peer networks are well known for their benefits when used for sharing data among multiple users. One of the most common protocols for shared data distribution is BitTorrent. Despite its popularity, it has some inefficiencies that affect the speed of the content distribution. In ...

On a constant arising in the analysis of bit comparisons in quickselect

African Journals Online (AJOL)

A (real) constant that appears as the factor of the leading term of the average number of bit comparisons required by quickselect, and was originally given in terms of complex numbers, is expressed using real numbers alone. A further representation is derived which is converging very quickly. Methods include residue ...

Implementation of an FIR Band Pass Filter Using a Bit-Slice Processor.

Science.gov (United States)

1987-06-01

SYSTEM ’ SOFTWARE FIRMWARE HARDWARE Figure 2.1 Instruction Levels CRef. 5] 16 are microprogrammed (firmware) to enable physical control signals to the...Controllers and ALUs, pp. 9, 30-42, 70-71, Garland STPM Press, 1981. 6. Wolfe, C.F., "Bit-slice Processors Come To Mainframe Design," Electronics

Microprocessor based systems for the higher technician

CERN Document Server

Vears, RE

2013-01-01

Microprocessor Based Systems for the Higher Technician provides coverage of the BTEC level 4 unit in Microprocessor Based Systems (syllabus U80/674). This book is composed of 10 chapters and concentrates on the development of 8-bit microcontrollers specifically constructed around the Z80 microprocessor. The design cycle for the development of such a microprocessor based system and the use of a disk-based development system (MDS) as an aid to design are both described in detail. The book deals with the Control Program Monitor (CP/M) operating system and gives background information on file hand

Robustness of spiking Deep Belief Networks to noise and reduced bit precision of neuro-inspired hardware platforms.