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Analysis of pseudo-random number generators in QMC-SSE method
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作者 刘东旭 徐维 张学锋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期75-79,共5页
In the quantum Monte Carlo(QMC)method,the pseudo-random number generator(PRNG)plays a crucial role in determining the computation time.However,the hidden structure of the PRNG may lead to serious issues such as the br... In the quantum Monte Carlo(QMC)method,the pseudo-random number generator(PRNG)plays a crucial role in determining the computation time.However,the hidden structure of the PRNG may lead to serious issues such as the breakdown of the Markov process.Here,we systematically analyze the performance of different PRNGs on the widely used QMC method known as the stochastic series expansion(SSE)algorithm.To quantitatively compare them,we introduce a quantity called QMC efficiency that can effectively reflect the efficiency of the algorithms.After testing several representative observables of the Heisenberg model in one and two dimensions,we recommend the linear congruential generator as the best choice of PRNG.Our work not only helps improve the performance of the SSE method but also sheds light on the other Markov-chain-based numerical algorithms. 展开更多
关键词 stochastic series expansion quantum Monte Carlo pseudo-random number generator
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Pseudo-randomness of the fourth class of GSS sequences 被引量:4
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作者 HU Yupu XIAO Guozhen 《Science in China(Series F)》 2004年第2期170-183,共14页
This paper discusses pseudo-randomness of a periodic sequence, named the fourth class of GSS sequence. We get the following results: ① Its least period always reaches the maximum (that is, 2n-1). ② Its least period ... This paper discusses pseudo-randomness of a periodic sequence, named the fourth class of GSS sequence. We get the following results: ① Its least period always reaches the maximum (that is, 2n-1). ② Its least period and linear complexity keep robust under single-symbol-substitution. ③ It has good low-degree-auto-correlation feature. ④ It has good short-length-run-distribution. 展开更多
关键词 GSS sequence M-SEQUENCE pseudo-randomness stream cipher.
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Pseudo-Randomness of Certain Sequences of k Symbols with Length pq 被引量:1
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作者 陈智雄 杜小妮 吴晨煌 《Journal of Computer Science & Technology》 SCIE EI CSCD 2011年第2期276-282,共7页
The theory of finite pseudo-random binary sequences was built by C. Mauduit and A. Sarkozy and later extended to sequences of k symbols (or k-ary sequences). Certain constructions of pseudo-random sequences of k sym... The theory of finite pseudo-random binary sequences was built by C. Mauduit and A. Sarkozy and later extended to sequences of k symbols (or k-ary sequences). Certain constructions of pseudo-random sequences of k symbols were presented over finite fields in the literature. In this paper, two families of sequences of k symbols are constructed by using the integers modulo pq for distinct odd primes p and q. The upper bounds on the well-distribution measure and the correlation measure of the families sequences are presented in terms of certain character sums over modulo pq residue class rings. And low bounds on the linear complexity profile are also estimated. 展开更多
关键词 stream ciphers pseudo-random sequences well-distribution measure correlation measure discrete logarithm modulo pq residue class rings character sums
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Application of pseudo-random frequency domain electromagnetic method in mining areas with strong interferences 被引量:7
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作者 Yan-fang HU Di-quan LI +2 位作者 Bo YUAN Guang-yun SUO Zi-jie LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第3期774-788,共15页
Due to the strong electromagnetic interferences and human interference,traditional electromagnetic methods cannot obtain high quality resistivity data of mineral deposits in Chinese mines.The wide field electromagneti... Due to the strong electromagnetic interferences and human interference,traditional electromagnetic methods cannot obtain high quality resistivity data of mineral deposits in Chinese mines.The wide field electromagnetic method(WFEM),in which the pseudo-random signal is taken as the transmitter source,can extract high quality resistivity data in areas with sever interference by only measuring the electric field component.We use the WFEM to extract the resistivity information of the Dongguashan mine in southeast China.Compared with the audio magnetotelluric(AMT)method,and the controlled source audio-frequency magnetotelluric(CSAMT) method,the WFEM can obtain data with higher quality and simpler operations.The inversion results indicate that the WFEM can accurately identify the location of the main ore-body,which can be used for deep mine exploration in areas with strong interference. 展开更多
关键词 pseudo-random signal frequency domain electromagnetic method wide field electromagnetic method(WFEM) strong interference anti-interference capability Dongguashan copper deposit
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Energy distribution and effective components analysis of 2^(n) sequence pseudo-random signal 被引量:6
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作者 Yang YANG Ji-shan HE Di-quan LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第7期2102-2115,共14页
In order to extract usable harmonics from real 2^(n) sequence pseudo-random data,a technical method is proposed.An equation for predicting the average amplitude of the main frequencies is proposed to guide the choice ... In order to extract usable harmonics from real 2^(n) sequence pseudo-random data,a technical method is proposed.An equation for predicting the average amplitude of the main frequencies is proposed to guide the choice of signal type for different exploration tasks.By the threshold of the amplitude of the transmitted signal,a set of candidate frequencies are first selected.Then,by operating a spectrum envelope method at these candidate frequencies on received data,effective components in data are extracted.A frequency density calculation method is proposed based on a logical number summation method,to reasonably characterize the frequency density in different frequency bands.By applying this method to real data in Sichuan,China,with signal Type 13,75 effective components are extracted,including both main frequencies and harmonics.The result suggests that the number of effective frequencies in the 2^(n) sequence pseudo-random signal can be increased by extracting usable harmonics,without any additional fieldwork. 展开更多
关键词 electromagnetic prospecting 2^(n) pseudo-random signal energy conservation harmonic extraction frequency density
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Blind parameter estimation of pseudo-random binary code-linear frequency modulation signal based on Duffing oscillator at low SNR 被引量:1
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作者 Ke Wang Xiaopeng Yan† +2 位作者 Ze Li Xinhong Hao Honghai Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期312-319,共8页
Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-no... Conventional parameter estimation methods for pseudo-random binary code-linear frequency modulation(PRBC-LFM)signals require prior knowledge,are computationally complex,and exhibit poor performance at low signal-to-noise ratios(SNRs).To overcome these problems,a blind parameter estimation method based on a Duffing oscillator array is proposed.A new relationship formula among the state of the Duffing oscillator,the pseudo-random sequence of the PRBC-LFM signal,and the frequency difference between the PRBC-LFM signal and the periodic driving force signal of the Duffing oscillator is derived,providing the theoretical basis for blind parameter estimation.Methods based on amplitude method,short-time Fourier transform method,and power spectrum entropy method are used to binarize the output of the Duffing oscillator array,and their performance is compared.The pseudo-random sequence is estimated using Duffing oscillator array synchronization,and the carrier frequency parameters are obtained by the relational expressions and characteristics of the difference frequency.Simulation results show that this blind estimation method overcomes limitations in prior knowledge and maintains good parameter estimation performance up to an SNR of-35 dB. 展开更多
关键词 Duffing oscillator pseudo-random binary code-linear frequency modulation(PRBC-LFM)signal blind parameter estimation low signal-to-noise ratio(SNR)
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Pseudo-Random Sequences Generator Based on Discrete Hyperchaotic Systems 被引量:1
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作者 Li Changgang & Han Zhengzhi Department of Automation, Shanghai Jiaotong University, Shanghai 200030, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第4期84-89,共6页
We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hype... We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hyperchaos. Then, we use three suchlike hyperchaotic systems with different feedback gain matrices to design a pseudo-random sequence generator (PRSG). Through a threshold function, three sub-sequences generated from the output of piecewise linear functions are changed into 0-1 sequences. Then, followed by XOR operation, an unpredictable pseudo-random sequence (PRS) is ultimately obtained. The analysis and simulation results indicate that the PRS, generated with hyperchaotic systems, has desirable statistical features. 展开更多
关键词 discrete hyperchaotic system piecewise linear state feedback pseudo-random sequences.
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HIERACHICAL STRUCTURES FOR GENERATING PSEUDO-RANDOM SEQUENCES AND ARRAYS
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作者 Shi Wenhong Chen Jinguang(Department of Radio Engineering, Fuzhou University, Fuzhou 350002) 《Journal of Electronics(China)》 1997年第1期20-26,共7页
This paper proposes new hierarchical structures for generating pseudorandom sequences and arrays. The principle of the structures is based on a new concept-multi-interleaving. It is the generalization of normal sequen... This paper proposes new hierarchical structures for generating pseudorandom sequences and arrays. The principle of the structures is based on a new concept-multi-interleaving. It is the generalization of normal sequence decimation(sampling). The kernal of the structures is a lower speed linear feedback shift register together with several high speed time-division multiplexers arranged hierarchically. These new structures have much higher speed compared with that of other schemes proposed before. 展开更多
关键词 pseudo-random SEQUENCES pseudo-random ARRAYS High-speed generation SEQUENCE DECIMATION
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Pseudo-Random Coding Side-Lobe Suppression Method Based on CLEAN Algorithm
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作者 Liyu Tian Lianjuan Zhang Jiaying Li 《Journal of Beijing Institute of Technology》 EI CAS 2017年第3期375-380,共6页
A pseudo-random coding side-lobe suppression method based on CLEAN algorithm is introduced.The CLEAN algorithm mainly processes pulse compression results of a pseudo-random coding,and estimates a target's distance by... A pseudo-random coding side-lobe suppression method based on CLEAN algorithm is introduced.The CLEAN algorithm mainly processes pulse compression results of a pseudo-random coding,and estimates a target's distance by a method named interpolation method,so that we can get an ideal pulse compression result of the target,and then use the adjusted ideal pulse compression side-lobe to cut the actual pulse compression result,so as to achieve the remarkable performance of side-lobe suppression for large targets,and let the adjacent small targets appear.The computer simulations by MATLAB with this method analyze the effect of side-lobe suppression in an ideal or noisy environment.It is proved that this method can effectively solve the problem due to the side-lobe of pseudo-random coding being too high,and can enhance the radar's multi-target detection ability. 展开更多
关键词 CLEAN algorithm pseudo-random coding pulse compression interpolation method
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BIT COMMITMENT USING PSEUDO-RANDOM SYNTHESIZER
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作者 Zheng Dong Liu Shengli Wang Yumin (ISN Key Lab., Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 1999年第4期372-375,共4页
This paper presents two practical message commitment schemes: one is suitable for committing many bits, and another is useful for committing any bit-long message. They are provably secure based on pseudo-random synthe... This paper presents two practical message commitment schemes: one is suitable for committing many bits, and another is useful for committing any bit-long message. They are provably secure based on pseudo-random synthesizers. In these schemes, the sender may be unbounded to polynomial time and the receiver is bounded. The advantage of these schemes is that the secure parameter may be small. 展开更多
关键词 BIT COMMITMENT pseudo-random SYNTHESIZER
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Adding Pseudo-Random Test Sequence Generator in the Test Simulator for DFT Approach
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作者 Afaq Ahmad Dawood Al-Abri Sayyid Samir AI-Busaidi 《Computer Technology and Application》 2012年第7期463-470,共8页
This paper presents modified version of a realistic test tool suitable to Design For Testability (DFT) and Built-ln Self Test (BIST) environments. A comprehensive tool is developed in the form of a test simulator.... This paper presents modified version of a realistic test tool suitable to Design For Testability (DFT) and Built-ln Self Test (BIST) environments. A comprehensive tool is developed in the form of a test simulator. The simulator is capable of providing a required goal of test for the Circuit Under Test (CUT). The simulator uses the approach of fault diagnostics with fault grading procedures to provide the optimum tests. The current version of the simulator embeds features of exhaustive and pseudo-random test generation schemes along with the search solutions of cost effective test goals. The simulator provides facilities of realizing all possible pseudo-random sequence generators with all possible combinations of seeds. The tool is developed on a common Personal Computer (PC) platform and hence no special software is required. Thereby, it is a low cost tool hence economical. The tool is very much suitable for determining realistic test sequences for a targeted goal of testing for any CUT. The developed tool incorporates flexible Graphical User Interface (GUI) procedures and can be operated without any special programming skill. The tool is debugged and tested with the results of many bench mark circuits. Further, this developed tool can be utilized for educational purposes for many courses such as fault-tolerant computing, fault diagnosis, digital electronics, and safe-reliable-testable digital logic designs. 展开更多
关键词 Digital system testing built-in self test design for testability test vector pseudo-random test sequence linear feedbackshift registers fault diagnosis fault collapsing realistic test fault cover iteration.
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10 Gbit/s PRBS tester implemented in FPGA 被引量:1
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作者 苗澎 王志功 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期516-519,共4页
The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BI... The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BIP-8) error detector is presented. Implemented in a parallel feedback configuration, this tester features PRBS generation of sequences with bit lengths of 2^7 - 1,2^10- 1,2^15 - 1,2^23 - land 2^31 - 1 for up to 10 Gbit/s applications with a 10 Gbit/s optical transceiver, via the SFI-4 (OC-192 serdes-framer interface). In the OC-192 frame alignment circuit, a dichotomy search algorithm logic which performs the functions of word alignment and STM-64/OC192 de-frame speeds up the frame sync logic and reduces circuit complexity greatly. The system can be used as a low cost tester to evaluate the performance of OC-192 devices and components, taking the replacement of precious commercial PRBS testers. 展开更多
关键词 bit interleaved polarity 8 BIP-8 synchronous digital hierarchy SDH FRAMER field programmable gate array (FPGA) pseudo-random binary sequence (PRBS)
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MULTI-BLOCK CHAINING-BASED AUTHENTICATION MODE
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作者 Huang Yuhua Hu Aiqun Zhong Ziguo 《Journal of Electronics(China)》 2006年第4期564-568,共5页
A fast authentication mode based on Multi-Block Chaining (MBC) is put forward; and its security is proved. The MBC mode is for new generation block cipher algorithms. Its speed is about 13% faster than that of the aut... A fast authentication mode based on Multi-Block Chaining (MBC) is put forward; and its security is proved. The MBC mode is for new generation block cipher algorithms. Its speed is about 13% faster than that of the authentication modes in common use (for example, cipher block chaining-message authentication code mode). The dependence test results meet the requirement. The MBC mode is complete; its degree of ava-lanche effect is about 0.9993; its degree of strict avalanche criterion is 0.992 or so. The frequency test results indicate that the output generated by the MBC mode has uniformity. The binary matrix rank test results imply that it is linear independent among disjoint sub-matrices of the output. Maurer’s universal statistical test results show that the output could be significantly compressed without loss of information. Run test, spectral test, non-overlapping template matching test, overlapping template matching test, Lempel-Ziv compression test, linear complexity test, serial test, approximate entropy test, cumulative sums test, random excursions test and random excursions variant test results fulfill the requirements of all. Therefore the MBC mode has good pseudo-randomness. Thus the security of MBC mode is verified by the way of statistical evaluation. 展开更多
关键词 Block cipher algorithm Authentication mode Statistical evaluation pseudo-randomness
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PERFECT PUNCTURED BINARY SEQUENCE PAIRS 被引量:15
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作者 JiangTing ZhaoXiaoqun HouLantian 《Journal of Electronics(China)》 2003年第4期285-288,共4页
This paper presents the definition of perfect punctured binary sequence pair and the combinatorial admissible conditions for searching the perfect punctured binary sequence pairs and proves that all of the pseudo-rand... This paper presents the definition of perfect punctured binary sequence pair and the combinatorial admissible conditions for searching the perfect punctured binary sequence pairs and proves that all of the pseudo-random binary sequences satisfy these conditions. Computer calculation verifies that the pseudo-random binary sequences with length up to N=127 can be easily turned into perfect punctured binary sequence pairs. 展开更多
关键词 Information theory Perfect sequences CODES pseudo-random binary sequence
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Distributed wide field electromagnetic method based on high-order 2^(n) sequence pseudo random signal 被引量:4
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作者 Yang YANG Ji-shan HE +1 位作者 Fan LING Yu-zhen ZHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1609-1622,共14页
To make three-dimensional electromagnetic exploration achievable,the distributed wide field electromagnetic method(WFEM)based on the high-order 2^(n) sequence pseudo-random signal is proposed and realized.In this meth... To make three-dimensional electromagnetic exploration achievable,the distributed wide field electromagnetic method(WFEM)based on the high-order 2^(n) sequence pseudo-random signal is proposed and realized.In this method,only one set of high-order pseudo-random waveforms,which contains all target frequencies,is needed.Based on high-order sequence pseudo-random signal construction algorithm,the waveform can be customized according to different exploration tasks.And the receivers are independent with each other and dynamically adjust the acquisition parameters according to different requirements.A field test in the deep iron ore of Qihe−Yucheng showed that the distributed WFEM based on high-order pseudo-random signal realizes the high-efficiency acquisition of massive electromagnetic data in quite a short time.Compared with traditional controlled-source electromagnetic methods,the distributed WFEM is much more efficient.Distributed WFEM can be applied to the large scale and high-resolution exploration for deep resources and minerals. 展开更多
关键词 distributed wide field electromagnetic method(WFEM) high-order pseudo-random signal MULTIFREQUENCY massive data
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A CLASS OF RANDOM NUMBER GENERATORS BASED ON WEYL SEQUENCE 被引量:1
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作者 Liang Heng Liu Qinghua Bai Fengshan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第4期483-490,共8页
The generation of good pseudo-random numbers is the base of many important fields in scientific computing, such as randomized algorithms and numerical solution of stochastic differential equations. In this paper, a cl... The generation of good pseudo-random numbers is the base of many important fields in scientific computing, such as randomized algorithms and numerical solution of stochastic differential equations. In this paper, a class of random number generators (RNGs) based on Weyl sequence is proposed. The uniformity of those RNGs is proved theoretically. Statistical and numerical computations show the efficiency of the methods. 展开更多
关键词 pseudo-random number randomized algorithm statistical test uniform distribution.
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Adaptive and Dynamic Mobile Phone Data Encryption Method 被引量:1
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作者 CAO Wanpeng BI Wei 《China Communications》 SCIE CSCD 2014年第1期103-109,共7页
To enhance the security of user data in the clouds,we present an adaptive and dynamic data encryption method to encrypt user data in the mobile phone before it is uploaded.Firstly,the adopted data encryption algorithm... To enhance the security of user data in the clouds,we present an adaptive and dynamic data encryption method to encrypt user data in the mobile phone before it is uploaded.Firstly,the adopted data encryption algorithm is not static and uniform.For each encryption,this algorithm is adaptively and dynamically selected from the algorithm set in the mobile phone encryption system.From the mobile phone's character,the detail encryption algorithm selection strategy is confirmed based on the user's mobile phone hardware information,personalization information and a pseudo-random number.Secondly,the data is rearranged with a randomly selected start position in the data before being encrypted.The start position's randomness makes the mobile phone data encryption safer.Thirdly,the rearranged data is encrypted by the selected algorithm and generated key.Finally,the analysis shows this method possesses the higher security because the more dynamics and randomness are adaptively added into the encryption process. 展开更多
关键词 data encryption mobile phone cloud storage pseudo-random number
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Designing a Secure Round Function Based on Chaos 被引量:1
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作者 Bin Lu Xin Ge Fenlin Liu 《China Communications》 SCIE CSCD 2020年第5期29-37,共9页
A round function based on chaos is designed combining Feistel structure’s pseudo-randomness, chaotic system’s parameter sensitivity and image data characteristics. The round function composes of two parts--data tran... A round function based on chaos is designed combining Feistel structure’s pseudo-randomness, chaotic system’s parameter sensitivity and image data characteristics. The round function composes of two parts--data transformation based on Feistel(abbreviated as FST) and sampling output based on chaos(abbreviated as SMP). FST bases on Feistel structure and several efficient operations including bitwise xor, permutation and circulating shift. SMP is a chaos based pseudo-random sampling algorithm. It is from theoretical analysis that the round function is a pseudo-random function. The upper bounds of the average maximum differential probability and average maximum linear probability are p^2 and q^2 respectively. Finally, the good pseudo-randomness of the round function is examined with the NIST random test. The design of this round function provides an important cryptographic component for the design of chaotic image encryption algorithm. 展开更多
关键词 image encryption round function CHAOS pseudo-random function
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Variant Map System to Simulate Complex Properties of DNA Interactions Using Binary Sequences 被引量:1
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作者 Jeffrey Zheng Weiqiong Zhang +2 位作者 Jin Luo Wei Zhou Ruoyu Shen 《Advances in Pure Mathematics》 2013年第7期5-24,共20页
Stream cipher, DNA cryptography and DNA analysis are the most important R&D fields in both Cryptography and Bioinformatics. HC-256 is an emerged scheme as the new generation of stream ciphers for advanced network ... Stream cipher, DNA cryptography and DNA analysis are the most important R&D fields in both Cryptography and Bioinformatics. HC-256 is an emerged scheme as the new generation of stream ciphers for advanced network security. From a random sequencing viewpoint, both sequences of HC-256 and real DNA data may have intrinsic pseudo-random properties respectively. In a recent decade, many DNA sequencing projects are developed on cells, plants and animals over the world into huge DNA databases. Researchers notice that mammalian genomes encode thousands of large noncoding RNAs (lncRNAs), interact with chromatin regulatory complexes, and are thought to play a role in localizing these complexes to target loci across the genome. It is a challenge target using higher dimensional visualization tools to organize various complex interactive properties as visual maps. The Variant Map System (VMS) as an emerging scheme is systematically proposed in this paper to apply multiple maps that used four Meta symbols as same as DNA or RNA representations. System architecture of key components and core mechanism on the VMS are described. Key modules, equations and their I/O parameters are discussed. Applying the VM System, two sets of real DNA sequences from both sample human (noncoding DNA) and corn (coding DNA) genomes are collected in comparison with pseudo DNA sequences generated by HC-256 to show their intrinsic properties in higher levels of similar relationships among relevant DNA sequences on 2D maps. Sample 2D maps are listed and their characteristics are illustrated under controllable environment. Visual results are briefly analyzed to explore their intrinsic properties on selected genome sequences. 展开更多
关键词 pseudo-random Number Generator STREAM CIPHER HC-256 Binary to DNA Pseudo DNA Sequence Large Noncoding DNA Analysis 2D MAP Visual Distribution VARIANT MAP System
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Design for Vibrator Field Experiment Based-on Vibrator-earth System 被引量:8
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作者 Chen Zubin Lin Jun +1 位作者 Liang Tiecheng Zhang Linhang 《Global Geology》 2000年第1期107-113,共7页
Source-generated energy in seismic vibrator records high frequency harmonic behavior. Conventional vibrator-earth coupling model was set up on the linear system. Some assumptions in the application of linear theory to... Source-generated energy in seismic vibrator records high frequency harmonic behavior. Conventional vibrator-earth coupling model was set up on the linear system. Some assumptions in the application of linear theory to the vibrator problem play an insignificant role in the overall coupling structure. Obviously, non-linear behaviors can be modeled using a “hard-spring” form of the Duffing equation. Model dedicates that a qualitatively similar harmonic component is present for a broad range of possible mathematical descriptions. After some qualitative analysis about the non-linear system, some conclusion can be drawn. Firstly, The design of the vibrator weight should be abided by two points as followed: In order to avoid decoupling for the vibrator to the earth, the weight should be greater than the peak of the driving force amplitude as to keep the resultant force pointing to the earth’s core. On the other hand, for the limited energy output, the vibrator overweight may damage the system high-frequency ability.Secondly, as the driving force frequency approaching to the ground hard-spring inherent frequency, the energy transmission was found to climb its peak from the system energy absorbed curve. At last, due to the non-linear coupling model system, its load curve would come into unstable frequency range, which might limit the application of the Vibroseis conventional sweeping pattern-linear sweep. A new sweeping pattern was listed: the driving signal was the pseudo-random sequence modulated by a fixed frequency cosine signal satisfying with the exploration precision and absorbing efficiency. The synthesized signal was ready to be realized by the electromagnetic driven system. Even the side-lobes noise of its auto-correlation function was restrained well. The theory coming from the Vibrator-earth coupling model was applied to the design of the Portable High-frequency Vibrator System (PHVS), and the good result was obtained. By the analysis of the vibrator base plate signal, the model was proved to be true. The exploration research on PHVS made a first step on its following optimal design. 展开更多
关键词 Portable High-frequency Vibrator System(PHVS) Coupling model Seismic prospecting Auto-correlation function Linear sweep pseudo-random sequence
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