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coded-Aperture imaging based on random code and Backpropagation neural network

ANNALS OF NUCLEAR ENERGY 2024年 195卷

作者： Wang, Zeyu Wang, Chao Gong, Pin Li, Liansheng Hu, Zhimeng Shi, Yongqiang Shen, Xiaolei Zhou, Cheng Zhu, Xiaoxiang Tang, Xiaobin Nanjing Univ Aeronaut & Astronaut Dept Nucl Sci & Technol Nanjing 210016 Peoples R China State Key Lab Intense Pulsed Radiat Simulat & Effe Xian 710024 Peoples R China Beijing Inst Control Engn Beijing 100094 Peoples R China Minist Ind & Informat Technol Key Lab Nucl Technol Applicat & Radiat Protect Ast Nanjing 210016 Peoples R China Jiangsu Nucl & Radiat Safety Supervis & Management Nanjing 210019 Peoples R China

coded-aperture radiation imaging technology has important application value in the field of space radiation detection. A coded-aperture imaging algorithm based on random code and Backpropagation neural network (BPNN) is proposed for high quality imaging of x-rays and gamma rays in space environments. The experimental results show that BPNN can improve the signal-to-noise ratio of the reconstructed image when applied to the reconstruction process of coded-aperture imaging based on random code. Therefore, it has a good application prospect in the field of space coded-aperture imaging.

关键词： coded-aperture imaging BPNN random code Monte Carlo simulation

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Improving the probability of complete decoding of random code by trading-off computational complexity

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IET COMMUNICATIONS 2015年第18期9卷 2281-2286页

作者： Chong, Zan-Kai Goi, Bok-Min Ohsaki, Hiroyuki Ng, Cheng-Kuan Bryan Ewe, Hong-Tat Univ Tunku Abdul Rahman Lee Kong Chian Fac Engn & Sci Selangor Malaysia Kwansei Gakuin Univ Sch Sci & Technol Tokyo Japan Victoria Univ Wellington Fac Engn Wellington New Zealand

random code is a rateless erasure code that can reconstruct the original message of k symbols from any k + 10 encoded symbols with high probability of complete decoding (PCD), i.e. 99.9% successful decoding, irrespective of the message length, k. Nonetheless, random code is inefficient in reconstructing short messages. For example, a message of k = 10 symbols requires k + 10 = 20 encoded symbols, i.e. two times the original message length in order to achieve high PCD. In this study, the authors propose micro-random code that encodes and decodes the original message using symbols of smaller dimensions, namely micro symbols. The authors' analysis and numerical simulations show that micro-random code achieves high PCD with only k + 1 encoded symbols. As the trade-off for such a gain, the number of steps for decoding increases exponentially with each incrementing segmentation factor, . In addition, the numerical results show that the decoding time increases by about 400% at = 10, depending on the processing power of the system.

关键词： probability random codes decoding computational complexity matrix algebra computational complexity rateless erasure code original message reconstruction microrandom code micro symbol segmentation factor random code complete decoding probability

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Probability of complete decoding of random codes for short messages

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ELECTRONICS LETTERS 2015年第3期51卷 251-U62页

作者： Chong, Zan Kai Goi, Bok-Min Ohsaki, Hiroyuki Ng, Bryan Ewe, Hong Tat Univ Tunku Abdul Rahman Petaling Jaya Selangor Malaysia Kwansei Gakuin Univ Nishinomiya Hyogo Japan Victoria Univ Wellington New Zealand

A random code is a rateless erasure code with a generator matrix of randomly distributed binary values. It encodes a message of k symbols into a potentially infinite number of coded symbols. For asymptotically large k, the tail bound in Kolchin's theorem asserts that the high probability of complete decoding (PCD) is attained almost surely with k + 10 coded symbols. However, for small values of k (short messages) it is unclear if such asymptotics are useful. That the random codes achieve a high PCD with k + 10 coded symbols for small k is demonstrated. In particular, a set of lemmas is established and show that the PCD converges to five decimal digits after k = 30. A theorem extending Kolchin's work is formulated and the theorem is used to explain the complete decoding probabilities of random codes in short messages.

关键词： probability random codes PCD distributed binary values generator matrix probability of complete decoding random code

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4-Sets-Cut-Decoding algorithms for random codes based on quasigroups

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AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS 2015年第10期69卷 1417-1428页

作者： Popovska-Mitrovikj, Aleksandra Markovski, Smile Bakeva, Verica Ss Cyril & Methodius Univ Skopje Fac Comp Sci & Engn Skopje Macedonia

The decoding speed is the biggest problem of random codes based on quasigroups proposed elsewhere. These codes are a combination of cryptographic algorithms and error-correcting codes. In our previous paper we proposed Cut-Decoding algorithm which is 4.5 times faster than the original one for code (72,288). In this paper, four new modifications (so-called 4-Sets-Cut-Decoding algorithms) of this algorithm are proposed in order to obtain an improvement of the decoding speed. We present and analyze several experimental results obtained with different algorithms for random codes based on quasigroups. It is shown that using new algorithms, improvement of the efficiency and decoding speed is obtained. Also, we derive the upper bound for packet-error probability obtained with Cut-Decoding and 4-SetsCut-Decoding algorithm. At the end, some methods for reducing the number of unsuccessful decodings in the new proposed algorithms are considered. (C) 2015 Elsevier GmbH. All rights reserved.

关键词： random code Error-correcting code Crypt-coding Packet-error probability Bit-error probability Quasigroup

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Performances of random codes Based on Quasigroups for transmission of audio files 23

Performances of Random Codes Based on Quasigroups for transm...

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20th Telecommunications Forum (TELFOR)

作者： Popovska-Mitrovikj, Aleksandra Ilievski, Vladimir Bakeva, Verica Univ Ss Cyril & Methodius Skopje Fac Comp Sci & Engn POB 393 Skopje Macedonia

ISBN: (纸本)9781509000555

Error-correcting codes can be applied for transmission of images and audio files through a noise channel. Application of random codes Based on Quasigroups (RCBQ) for image transmission is considered elsewhere. In this paper we investigate performances of these codes for transmission of audio files through a binary-symmetric channel. We present and analyze several experimental results obtained using Cut-Decoding and 4-Sets-Cut-Decoding algorithms defined for RCBQ. In the experiments we use code (72, 576) with rate 1/8. We made experiments with Beethoven's "Ode to Joy".

关键词： random code cryptcoding error-correcting code packet-error probability bit-error probability audio file

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Quasi-Cyclic codes of Index 1 1/3

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IEEE TRANSACTIONS ON INFORMATION THEORY 2016年第11期62卷 6342-6347页

作者： Fan, Yun Liu, Hualu Cent China Normal Univ Sch Math & Stat Wuhan 430079 Peoples R China

We introduce quasi-cyclic codes of index 1(1/3), and construct a class of such codes generated by pairs of polynomials. By investigating the pair of circulant matrices associated with the generator pair of polynomials, we obtain the generator matrix of any code of the class. Using a probabilistic method, we prove that, for any positive real number delta such that the asymptotic GV-bound at 2 delta is greater than 1/2, the probability that the relative minimal distance of the code in the class is greater than d is almost 1;and the probability that the rate of the code equals to 1/4 is also almost 1. An obvious consequence is that the quasicyclic codes of index 1(1/3) are asymptotically good.

关键词： Quasi-cyclic code fractional index relative minimum distance random code asymptotically good code

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The Arbitrarily Varying Channel With Colored Gaussian Noise

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IEEE TRANSACTIONS ON INFORMATION THEORY 2021年第6期67卷 3781-3817页

作者： Pereg, Uzi Steinberg, Yossef Tech Univ Munich Inst Commun Engn D-80333 Munich Germany Technion Israel Inst Technol Dept Elect Engn IL-3200003 Haifa Israel

We address the arbitrarily varying channel (AVC) with colored Gaussian noise. The work consists of three parts. First, we study the general discrete AVC with fixed parameters, a model that combines the AVC and the time-varying channel. We determine both the deterministic code capacity and the random code capacity. Super-additivity is demonstrated, showing that the deterministic code capacity can be strictly larger than the weighted sum of the parametric capacities. In the second part, we consider the arbitrarily varying Gaussian product channel (AVGPC). Hughes and Narayan characterized the random code capacity through min-max optimization leading to a "double" water filling solution. As in the case of the standard Gaussian AVC, the deterministic code capacity is discontinuous in the input constraint, and depends on which of the input or state constraint is higher. As opposed to Shannon's classic water filling solution, it is observed that deterministic coding using independent scalar codes is suboptimal for the AVGPC. Finally, we establish the capacity of the AVC with colored Gaussian noise, where double water filling is performed in the frequency domain. The analysis relies on our preceding results, on the AVC with fixed parameters and the AVGPC.

关键词： Jamming Gaussian noise Resource management Optimization Frequency-domain analysis Wireless communication Transmitters Arbitrarily varying channel water filling colored Gaussian noise time varying channel Gaussian product channel deterministic code random code

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NONCONVEXITY OF THE CAPACITY REGION OF THE MULTIPLE-ACCESS ARBITRARILY VARYING CHANNEL SUBJECT TO CONSTRAINTS

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IEEE TRANSACTIONS ON INFORMATION THEORY 1995年第1期41卷 3-13页

作者： GUBNER, JA HUGHES, BL JOHNS HOPKINS UNIV DEPT ELECT & COMP ENGNBALTIMOREMD 21218

The random-code capacity region of the multiple-access arbitrarily varying channel subject to both state and input constraints is determined. Consideration of a simple erasure channel shows that the capacity region is... 详细信息

关键词： random code MULTIPLE-ACCESS CHANNEL ARBITRARILY VARYING CHANNEL STATE CONSTRAINT INPUT CONSTRAINT CONVEXITY

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Tardos fingerprinting is better than we thought

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IEEE TRANSACTIONS ON INFORMATION THEORY 2008年第8期54卷 3663-3676页

作者： Skoric, Boris Vladimirova, Tatiana U. Celik, Mehmet Talstra, Joop C. Philips Res Labs NL-5656 AE Eindhoven Netherlands Philips Content Identificat NL-5656 AE Eindhoven Netherlands Accenture Nederland NL-1082 MA Amsterdam Netherlands

Tardos has proposed a randomized fingerprinting code that is provably secure against collusion attacks. We revisit his scheme and show that it has significantly better performance than suggested in the original paper. First, we introduce variables in place of Tardos' hard-coded constants and we allow for an independent choice of the desired false positive (FP) and false negative (FN) error rates. Following through Tardos' proofs with these modifications, we show that the code length can be reduced by more than a factor of two in typical content distribution applications where high FN rates can be tolerated. Second, we study the statistical properties of the code. Under some reasonable assumptions, the accusation sums can be regarded as Gaussian-distributed stochastic variables. In this approximation, the desired error rates are achieved by a code length twice shorter than in the first approach. Overall, typical FP and FN error rates may be achieved with a code length approximately five times shorter than in the original construction.

关键词： coalition collusion fingerprinting random code traitor tracing watermark

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Simulated evolution applied to study the genetic code optimality using a model of codon reassignments

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BMC BIOINFORMATICS 2011年第1期12卷 1-8页

作者： Santos, Jose Monteagudo, Angel Univ A Coruna Dept Comp Sci La Coruna 15071 Spain

Background: As the canonical code is not universal, different theories about its origin and organization have appeared. The optimization or level of adaptation of the canonical genetic code was measured taking into account the harmful consequences resulting from point mutations leading to the replacement of one amino acid for another. There are two basic theories to measure the level of optimization: the statistical approach, which compares the canonical genetic code with many randomly generated alternative ones, and the engineering approach, which compares the canonical code with the best possible alternative. Results: Here we used a genetic algorithm to search for better adapted hypothetical codes and as a method to guess the difficulty in finding such alternative codes, allowing to clearly situate the canonical code in the fitness landscape. This novel proposal of the use of evolutionary computing provides a new perspective in the open debate between the use of the statistical approach, which postulates that the genetic code conserves amino acid properties far better than expected from a random code, and the engineering approach, which tends to indicate that the canonical genetic code is still far from optimal. We used two models of hypothetical codes: one that reflects the known examples of codon reassignment and the model most used in the two approaches which reflects the current genetic code translation table. Although the standard code is far from a possible optimum considering both models, when the more realistic model of the codon reassignments was used, the evolutionary algorithm had more difficulty to overcome the efficiency of the canonical genetic code. Conclusions: Simulated evolution clearly reveals that the canonical genetic code is far from optimal regarding its optimization. Nevertheless, the efficiency of the canonical code increases when mistranslations are taken into account with the two models, as indicated by the fact that the best possible co

关键词： Codon Genetic code Standard code random code Mean Square

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