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Improving the material machining by improving various input conditions promotes the functional stability of the component with high reliability and claims goodwill to the concern. The primary objective of this research is to experimentally examine how much materials can be removed with the help of a CNC turning center with respect to unit time from the material of Aluminum alloy Al-Si12CU by selecting of suitable tool or tool coating. Silicon Insert is conventionally employed (Control group) and WCC-coating on it is proposed (experimental group). A cylindrical bar of Al-Si12CU alloy, with dimensions 50mm in diameter and 20mm long the workpiece. The Control group workpieces (the predicted number of sample machining on workpieces with 80% G power setting was 20 for each group) were machined under the same working conditions with uncoated Silicon nitride inserts whereas the experimental group samples were machined with WCC-coated silicon nitride inserts. The material removal rate (MRR) calculated for machining the Al-Si12CU alloy was according to ASTM standards. The observations of MRR were statistically tested, the average performance by the coated tool was 1.801 mm3/min whereas it was for the uncoated tool 1.624 mm3/min. The probability of error was 0.3% and it was less than 5%. The observations are acceptable, and the proposed tool has significantly high performance in terms of MRR. This suggests that the WCC-coated silicon nitride inserts outperform the uncoated ones in terms of MRR. The findings affirm the effectiveness of the experimental design and highlight the substantial variance between the two groups. In summary, this investigation demonstrates that using WCC-coated silicon nitride inserts leads to a higher MRR when turning Al-Si12CU alloy compared to uncoated silicon nitride inserts. [ABSTRACT FROM AUTHOR]

The integration of human factors analysis and process safety management has emerged as a critical strategy for mitigating exposure to hazardous substances and consequential incidents. Given that human factors and behavior are major contributors to industrial accidents, the identification and assessment of human errors and their associated probabilities have become essential. In response, the Cognitive Reliability and Error Analysis Method (CREAM) was employed to seamlessly incorporate human factors into process safety management and to analyze human errors. This research aims to explore the factors that contribute to human-related incidents and to ascertain the probabilities of human errors within the chemical industry. Utilizing the CREAM methodology, the objective is to proactively reduce or prevent such errors. The creation of a CREAM Template within Microsoft Excel followed a comprehensive parameter study. Subsequently, insights were gathered from industry experts and on-site personnel, enriching the CREAM system with contextual data. Validation of the CREAM system was conducted by an experienced evaluator to ensure parameter accuracy. The resultant data underwent rigorous analysis and were benchmarked against industry standards. Notably, the likelihood of a human error occurring within one of the company's Hierarchical Task Analyses (HTAs) was determined to be 0.01152. During data collection, an in-depth analysis of parameters contributing to human incidents was also conducted. Furthermore, human errors were identified for each task step, with the highest error rate associated with the cognitive function of execution, reaching 64.71%. In conclusion, the CREAM system equips experts to pinpoint human errors and their probabilities, enabling proactive measures to prevent incidents from occurring. [ABSTRACT FROM AUTHOR]

The article considers the solution of the problem of pattern recognition with a given error and reliability, when the classes of the training sample are separated from each other with an error in the feature space, the dimension of which has an upper limit value. A method is presented for finding the upper bound on the size of the feature space, taking into account such parameters as the frequency of errors in the erroneous separation of each class of the training sample from other classes, the probability of error in recognition and its reliability, as well as the number of classes, features and objects in the training sample. In order to form a finite-dimensional space from individual class-specific features, the minimum and real separating strength of each selected individual feature is determined. Procedures for the formation of a finite-dimensional space from each type of individual features of the second and third types are proposed, taking into account their minimum and real separating forces. Based on the proposed methodology, an algorithm and software were developed. Computational experiments were carried out on a computer, and the results were presented in the form of decision rules, according to which new images were recognized. The conclusions of the study are also presented. [ABSTRACT FROM AUTHOR]

In this paper, is derived the reliability of an n-cascade stress-strength system based on the Rayleigh Distribution (RD) with unknown parameter λ is calculated in this paper for the probability of n-components having strengths Y between two stresses X and Z. There are six methods of parameter estimation in the Rayleigh Distribution, and these system reliability estimators were discussed using the Maximum Likelihood, Moments Method, Least Square Method, Weighted Least Square Method, Regression Method, and Percentile Method, estimators are based on simulation technique, and these estimates were compared by the mean square error using nine different experiments with different sample sizes: small (15), medium (25) and large (100). The maximum likelihood estimator and the percentile estimator were performed and the results all of the other options. [ABSTRACT FROM AUTHOR]

The visualization subsystem in virtual simulators is one of the most important components, as it provides the necessary level of trainable immersion in virtual space. The choice of optimal visualization components is a non-trivial task solved on the basis of an expert approach, which allows for the possibility of errors both in the architecture of this subsystem and in the parameters. The paper proposes an algorithm for selecting visualization components for virtual training systems, based on correlation matrices for quantitative and qualitative evaluation of components. The values of the matrices were obtained on the basis of experimental studies and comparison of components on a set of typical simulators, which make it possible to evaluate the components according to the metrics of the quality of display, interaction, movement, and sound. The proposed approach allows to reduce the probability of errors in the synthesis of the visualization subsystem of virtual training systems. [ABSTRACT FROM AUTHOR]

Localization is one of the fundamental problems of autonomous robots. This problem is related to determining the position of a mobile robot from sensor data. However, the mostly solution to localization problems is passive, meaning they do not manage the opportunity to control the robot's effectors during localization. This paper proposes an active localization approach, which is Markov localization. Markov localization provides rational criteria for setting the robot's motion direction (exploration) and determining the pointing direction of the sensors to localize the robot most efficiently. Furthermore, it can deal with noisy sensors and approximative world models, which is far more beneficial. After the demonstration in a structured environment of 5×5 boxes area, Markov can find the actuator position within four steps. The error probability reading shows a result of 3/100 for the highest and 1/100 for the lowest. The corresponding error measurement is discussed. [ABSTRACT FROM AUTHOR]

The article describes the application of the technology of the digital twin of the person to solve the problem of tasks distribution of in modern production. The person is a cyber-physical system; therefore, it is possible to create his digital twin with characteristics and properties that are important for us. From the point of view of modern production, a person is a production resource that has certain characteristics and is capable of performing certain work. The task of the planner in production is to optimally distribute tasks among production resources whether is a robot or a person. It is necessary to take into account not only the cost of work, but also other important parameters, such as the probability of error, injury, etc. The complexity is also added by the fact that the characteristics of a person are not constant, depend on many factors and change even during the work shift. It is necessary to take into account all these parameters when distributing tasks, as well as to track them in dynamics in order to transfer the work performance to the resource that is optimal for this on time. [ABSTRACT FROM AUTHOR]

In the digital age, cyber threats pose an increasing danger, especially for critical information infrastructure [1-2], including energy objects [3-8]. The task of ensuring the cybersecurity of automatic control systems at electric power objects, such as relay protection devices, the regime, and emergency control devices, automated process control systems, is extremely important [9-11]. Cybersecurity issues include not only the problems of hacker attacks but also the whole complex of problems of adequate functioning of cybernetic systems. The most acute problem of cybersecurity is in the power distribution complex, especially in that part of it that is not part of vertically integrated companies. A methodological approach is considered to analyze the structure of the construction of automatic means of the regime and emergency control in the aspect of the impact of their cyber vulnerabilities on the reliability of power supply to consumers. [ABSTRACT FROM AUTHOR]

The article examines a model of an information system for the hidden transmission of a control signal. The model describes the conditions for the synchronization of the receiver and the transmitter when transmitting a control signal over a channel with a relatively high level of interference, depending on the properties of the channel and the length of the framing pulse crnxponocb1Ka. An analytical expression is obtained for the probability of system synchronization with hidden transmission of a control signal, depending on the level of noise in the channel and the length of the initializing sequence. The behavior of the function characterizing the probability of synchronization for noisy channels is investigated. [ABSTRACT FROM AUTHOR]

Automation of the routine tasks of institutes allows for the reduction of the processing time of admission applications and reduces the probability of human errors. For this study, two tasks that needed to be automated using information technology were selected - building analytical reports (working with OLAP data cubes) and optical recognition of elements of manually filled forms in Python. As a result of the introduction of automation, the tasks described in the work began to require minimal manual intervention and the processing time decreased greatly. With further iterations to optimize the work of institutes, new opportunities will appear to accelerate the processing of large volumes of applications. [ABSTRACT FROM AUTHOR]

In this work, we proposed Offset-Quadrature Amplitude Modulation (OQAM) for Discrete Wavelet Transform (DWT) as alternative of Multi-Carrier Modulation (MCM) systems. Instead of the upsampler in the conventional DWT-MCM, OQAM is used in each level. In OQAM, each symbol will be separate into two components, in-phase and quadrature. With OQAM, maximum phase variation will decrease to its half value, which means that the performance of the RF power amplifier will improved. In addition, half symbols period will offset (stagger) the quadrature and in-phase components of the modulated signal to achieve low bit error rate. By contrast, in conventional orthogonal frequency division multiplexing (OFDM), without using the guard interval (Cyclic Prefix (CP)), inherent interferences cause degeneration in received symbols. In this paper, the proposed system model enhanced the spectrum efficiency and becomes more robust to the frequency selective environments. The simulation results illustrate that our proposed system model improves the system performance in terms of probability of errors compared with the OFDM system. [ABSTRACT FROM AUTHOR]

The article substantiates the need to switch to wireless channels of the optical range for communication with mobile objects. The relevance of the topic is due to the growing need to increase the speed of information transfer. This is due to the introduction of unmanned technologies in railway transport, which involve a constant exchange of data between the rolling stock and the traffic control center. The limited capacity of radio channels does not allow remote control of trains. This problem can be solved by switching communication channels with mobile objects to the optical wavelength range. To implement projects for the introduction of wireless optical communication, it is necessary to ensure the required range and quality of communication. This problem can be solved by increasing the optical budget of the wireless optical communication channel (BOX) by increasing the sensitivity of the photodetectors and the corresponding signal-to-noise power ratio. This way is more rational than increasing the laser power. For this purpose, the article proposes to use new nanoelectronics materials based on enriched semiconductors. As evidence, the results of studies of the influence of the concentrations of heavy isotopes on the band gap of semiconductors, as well as the light absorption coefficients and quantum efficiency are presented. Calculation of the communication quality in the form of the error probability of an elementary pulse at the output of the photodetector showed that enriched materials in the form of multiple quantum wells provide the error probability by two orders of magnitude less than natural semiconductors. Thus, the obtained gain in the signal-to-noise ratio at the output of the photodetector due to new materials can be used: a) to improve the quality of communication, which is important in conditions of atmospheric interference; b) to increase the communication range, which is important for a moving object. [ABSTRACT FROM AUTHOR]

In this article, we describe the developed program package intended for synthesis of the logical part of Emergency Protection Systems (EPS). The Emergency Protection Systems are used in modern control devices for hazardous production facilities, and they are subject to especially high requirements for reliability and response speed. The logical structures of emergency protection systems are complex and difficult to design. Theoretical calculations were made and a program was developed to automate the design of the logical part of emergency protection systems. Calculation is made on the basis of sequence equations, including minimization of initial logical functions using the developed method of finding the minimization option with the least labor input. In this article we considered the sequence of work with the program and the features of setting calculation conditions. The software package simplifies the process of synthesis of the logical part of Emergency Protection Systems and reduces the probability of design errors. [ABSTRACT FROM AUTHOR]

The study of seismicity in the Black Sea region is of particular interest for assessing the vulnerability of the surrounding coastal zones to strong earthquakes and their consequences. The seismicity pattern in the area is determined by the geodynamic processes along the boundaries of the Eurasian, Anatolian and Arabian tectonic plates. The paper presents an approach to assessing the seismic activity of the Black Sea and the surrounding region covering historical and recent seismicity. The historical events since after Christ are included in the catalogue compiled in our previous study, which contains 6468 de-clustered events from 1905 to 2021 with a magnitude M?3. All catalogue data are processed by ZMAP, which is routinely applied in the seismological practice to evaluate catalogue quality and in routine network operations. Based on the Frequency-Magnitude Distribution of the overall catalogue, we compiled the magnitude of completeness Mc, b-value and probability maps with their error evaluations for the two periods: recent seismicity (1977-2021) and including historical events, respectively. The catalogue data show a significant increase in small to moderate (3.0?M<5.0) earthquakes after 1980. The considerable increase in the number of seismic stations installed in the countries bordering the Black Sea increases the sensitivity to earthquake detection capability. The seismic events are clustered to the strongest (M?6) earthquakes and outlined the main seismic zones: Shabla-Kaliakra, the Crimean peninsula, three clusters located on the eastern shores of the Black Sea, and one on the southern coast near Bartin, Turkey. These seismic zones outline tectonic units, with specific seismicity patterns in the locations of the clusters. [ABSTRACT FROM AUTHOR]

Quantum cryptography provides methods for secret key distribution between the two distant users. An important step in quantum key distribution protocols is the correction of errors that occur during the transmission and implementation of the protocol. Here we consider error estimation and error correction with linear codes such as repetition code, Hamming code, low density parity check (LDPC) code. The paper investigates the increase in the efficiency of error correction using a combination of a repetition code and a LDPC code for a high error probability. [ABSTRACT FROM AUTHOR]

This article deals with effect of signals with phase and quadrature amplitude modulation on the reception of signals with quadrature amplitude modulation. Numerical simulation of the bit error rate and symbol error rate is performed using the MATLAB/Simulink software environment. Based on the results of calculations, it was found that the impact of signals with QPSK modulation causes more bit errors than the impact of signals with 16-QAM modulation. The presence of a frequency shift between the information and interference signal increases the bit error rate, which is associated with the rotation of the signal constellation. Increasing the probability of bit errors with frequency shift increasing occurs up to the limit frequency, depending on the length of the considered bit sequence. [ABSTRACT FROM AUTHOR]

This article proposes an approach to comparing the criteria that are used in the analysis of time series of parameters for registering the state of complex technical objects. The approach is based on the establishment of an important characteristic of trend criteria (namely: the power of the criteria), which are considered as criteria for distinguishing composite hypotheses. A statistical model of data generation in the form of a set of deterministic trend and random components is proposed for analysis. The deterministic component is considered in the form of a linear approximation of its expansion in the Taylor series. The random component is represented as a sample from the general population of independent random variables that have a normal distribution. The most frequently encountered trend criteria were selected for analysis: Student's test for equality of means; Fisher's variance ratio test; correlation criterion and its varieties. The supporting hypothesis has the form of the time series belonging to a sample from the general population of independent random variables, and the alternative one - belonging to a sample with a linear trend. Trend statistics of the considered criteria are generated on a sliding or sectional non-overlapping analysis window of a given dimension. As a parameter of the trend development, we choose the ratio of the trend growth during the analysis to the mean-square deviation (MSD) of the random component. For the considered trend criteria, the dependences of their power on the trend development parameter and the probability of errors of the first kind (false alarm) were obtained, as well as the operational characteristics of the criteria. The analysis was carried out by methods of analytical estimates and statistical modeling. Comparison of trend criteria for power at equal values of the probability of errors of the first kind allows us to establish the advantage of the Student and Fisher criteria, and the correlation criterion has the worst indicators. Obtaining power indicators for trend criteria is of great practical importance, since it allows us to establish the probability of errors of the second kind (trend skipping). [ABSTRACT FROM AUTHOR]

Blood grouping is the first and foremost essentiality for many of the major medical procedures. Traditional ways of detecting blood group have remained analogue in this era of digitization and are therefore susceptible to human fallibility. Digital methods are essential in handling blood group identification and classification reduces error. So it would be very efficient and arguably a lifesaving approach if the process of detecting blood can be completed successfully in a cost effective way with the technologies at hand and without the plausibility of man-made error. This proposition is expected to evaluate the Rh factor as well as the group of a sample blood with its computed image. The whole process excludes a major probability of human error while detecting the agglutination from the traditional method and it would get the task done within a fairly insignificant amount of time. The procedure will start by taking a photo of the sample blood slide followed by the application of a number of algorithms such as grey scale, binary and canny edge detection on it. After that, the detected edges will be counted and thus we will decide the agglutination. The method is established upon real-time dataset including 100 blood samples of people of different ages. The experimental result is almost accurate compared to the real time results from the sample dataset. It can, therefore, conclude the procedure with certain numeric values which were determined after realtime data analysis of images from a Camera, to make it simpler and more precise. [ABSTRACT FROM AUTHOR]

Applications of electronic map from mobile phone have helped drivers finding travel destinations. These applications were often used by driver as guidance when he was driving. There were some factors caused traffic accident that endanger individuals. Among these factors, human error was the main factor that caused traffic accidents. This research aims analyzing the effect of using electronic maps while driving on human error probability. This research used goggle map application as secondary task on driver. Human Error Assessment and Reduction Technique (HEART) were used to analyze human error probability and its output be compared to drivers shelves report. The reports include incident and accident that have been experienced by drivers along driving while using electronic map. The value of human error probability on this condition was 0.0106 and according to driver subjective judgment, the drivers never had experienced on incidents and accidents. However sometime a driver got a warning from another driver because he inhibited the traffics. A procedure driving safely while using electronic map was designed to minimize accident and protest from others driver. This research concluded this driving activity increased human error probability very slight and it will safe if driver allow the procedure. [ABSTRACT FROM AUTHOR]

The Coarse Wavelength Division Multiplexing (CWDM) system presented in this paper has several distinct characteristics from the standard CWDM system. One of them is the channel spacing whereby it uses smaller channel spacing compared to the standard system. The other is that, the system uses a broad spectrum laser source. The source is filtered by using ‘Bragg Grating’ before being transmitted. The filtration gives higher OSNR compared to standard CWDM setup. It was found that the system can transmit through each channel up to 2.5 Gbps with the probability of error of 10-12. The maximum distance that can be supported by this system is about 27 km, for the data rate of 155 Mbps. [ABSTRACT FROM AUTHOR]

As an important part of resource allocation, power allocation affects the performance of wireless cooperative system to a great extent. However, the existing cooperative communication power allocation scheme using only a single index to optimize the performance of the system makes the optimization effect unideal, put forward a cooperative communication power allocation scheme comprehensively consider of the capacity and error probability as objective function. In this paper, the capacity and error probability of the cooperative communication technology are analyzed and the corresponding theoretical formulas are derived, then prove the nonlinear relationship between the two. On this basis, make the maximizing the capacity and minimizing error probability as objective function, present the power allocation scheme based on particle swarm optimization. The simulation results show that the proposed scheme has better effect on cooperative communication system, and is more suitable for the future development of cooperative communication technology. [ABSTRACT FROM AUTHOR]

Near threshold computing (NTC) through aggressive supply voltage scaling has the potential to significantly improve energy-efficiency. However, the increase in variation-induced timing errors is a major challenge in NTC. This can be addressed in the scope of approximate computing by selectively embracing non-important variation-induced timing errors. In this paper, we propose a framework to leverage the error tolerance potential of approximate computing for energy-efficient NTC designs. In our framework, statistical timing error analysis as well as structural and functional error propagation analysis is performed to identify the approximable portion of a design. Then, a mixed-timing logic synthesis is employed to improve energy-efficiency by embracing errors in the approximable portion of the design. Experimental results show that the proposed approach can improve the energy-efficiency of NTC designs by more than 30%. [ABSTRACT FROM AUTHOR]

With the emerging nanoscale CMOS technology, Multiple Event Transients (METs) originated from radiation strikes are expected to become more frequent than Single Event Transients (SETs). In this paper, a fast and accurate layout- based Soft Error Rate (SER) estimation technique with consideration of both SET and MET fault models is pro- posed. Unlike previous techniques in which the adjacent MET sites are obtained from logic-level netlist, we perform a comprehensive layout analysis to extract MET adjacent cells. It is shown that layout-based technique is the only effective solution for identification of adjacent cells as netlist-based techniques significantly underestimate the overall SER. [ABSTRACT FROM AUTHOR]

Choosing the correct error injection technique is of primary importance in simulation-based design and evaluation of robust systems that are resilient to soft errors. Many low-level (e.g., flip-flop-level) error injection techniques are generally used for small systems due to long execution times and significant memory requirements. High-level error injections at the architecture or memory levels are generally fast but can be inaccurate. Unfortunately, there exists very little research literature on quantitative analysis of the inaccuracies associated with high-level error injection techniques. In this paper, we use simulation and emulation results to understand the accuracy trade-offs associated with a variety of high-level error injection techniques. A detailed analysis of error propagation explains the causes of high degrees of inaccuracies associated with error injection techniques at higher levels of abstraction. [ABSTRACT FROM AUTHOR]

Cognitive radio (CR) is a technology that addresses the problem of scarcity of spectrum and paves the way for efficient use of the same. In recent times, it has been observed that most research is focused on building theoretical models which are backed mostly by simulation results. In order to successfully support any theoretically developed model, it is necessary that the algorithm be tested in practical environment using hardware. Since some assumptions made to satisfy simulation requirements may not hold under practical circumstances, the implementation and testing of a theoretical concept is quite challenging. In this paper, we present experimental test results from our implementation of improved energy detector for single node and co-operative CR networks. The theoretical model is taken from [1], while GNU Radio and universal software radio peripherals 2 (USRP2) kits serve as software and hardware, respectively, in the implementation. Shadowed fading (due to obstacles and hidden node problem) makes single node sensing sometimes unreliable. Use of cooperation among secondary nodes, along with proper fusion rules, not only exploits the advantage of spatial diversity but also improves the reliability of spectrum hole sensing, as evident from the test results. It has been demonstrated by using the practical testing that cooperative sensing is better than single node sensing. [ABSTRACT FROM PUBLISHER]

In this paper, the performance of cooperative spectrum sensing with multiple antennas at each cognitive radio (CR) has been assessed in both Hoyt faded and non-faded (additive white Gaussian noise) environments. The CRs which employ improved energy detector (IED) utilize selection combining (SC) of the decision statistics obtained by IEDs for making hard decisions about the presence or absence of a primary user (PU). We analytically derive expressions of probability of missed detection in both the environments. Several types of hard decision fusion rules such as OR rule, AND rule and MAJORITY rule are investigated at fusion center (FC) to obtain the final decision about PU. Comparison among the fusion rules has been carried out for a wide range of average signal-to-noise ratio (SNR) values in Hoyt fading environment. The performance has been assessed in terms of missed detection and false alarm probabilities in both the environments. The performance has also been investigated in terms of total error probability for different values of IED parameter (p), normalized detection threshold, different number of antennas and number of CRs in Hoyt fading environment. Impact of Hoyt fading parameter on detection performance is indicated. [ABSTRACT FROM PUBLISHER]

We investigate the performance of a two-way relay (TWR) assisted Free Space Optical (FSO) system over weak atmospheric turbulence channels. A dual-hop bi-directional relaying system which consists of three nodes is considered. Closed form expression for its outage performance is derived assuming a fixed-gain relay and considering decode-and-forward (DF) protocol. Additionally, we study its error performance by calculating the moment generating function (MGF). [ABSTRACT FROM PUBLISHER]

This paper presents a comprehensive approach to the smart application of redundancy techniques in multiple-layer hierarchical systems. Computing systems today are rapidly evolving into increasingly complex structures with an ever-increasing number of components. Moreover, future technology generations are expected to have associated lower levels of quality. For these reasons, it is emerging nowadays a renewed interest in the development of reliable architectures. In this work we delve into this topic putting special emphasis on the system hardware hierarchy. We analyze the advantages in terms of reliability of distributing redundancy effort in cross-layer systems. We base our analysis on a general fault model that takes into account both devices and interconnections. Using the Rent's Law we relate the number of devices and interconnections for different configurations of redundancy and compare the global error probability. Our results provide meaningful information about the benefits that can be achieved by properly choosing the system layer at which to apply redundancy, and if applicable, the optimal distribution of redundancy effort through the system layers. [ABSTRACT FROM PUBLISHER]

In this paper we present a design concept for a new family of Improved Nyquist Filters (INFs). The filters performance, in terms of error probability, depends on the presence of symbol timing errors for the same values of the excess bandwidth, timing jitter, signal to noise ratio and number of interfering pulses. The characteristic property of the new family of inter-symbol interference (ISI) free pulses generated by the proposed filters is the asymptotic decay rate of t−1 and t−2. The proposed design concept to construct Nyquist filters is based on a piece-wise frequency characteristic, composed of two or three linear pieces in the transition region with different slopes. Analytical and simulation results are presented to show that improvements can be achieved as compared to previously reported pulses taken as references. [ABSTRACT FROM PUBLISHER]

In this work we explore the decoding process when information words have different semantic values. In that setting, we introduce a convenient loss function that allows us to express the overall performance of a decoding scheme for discrete channels, switching the usual goal of minimizing the error probability to that of minimizing the expected loss. [ABSTRACT FROM AUTHOR]

In this paper, we consider a binary decision fusion problem for a wireless sensor network, with flat Rayleigh fading, where the sensors make local binary decisions on the status of a common binary phenomenon. A training-based channel estimator is used at the fusion center (FC) to estimate the complex Gausssian fading coefficients characterizing the (direct) links between sensors and FC. This (estimated) channel state information is used, by proper thresholding, to censor the sensors. On the other hand, a locally optimal decision threshold is considered for binary quantization at the sensors. The average detection error probability at the FC, under the use of a majority logic fusion rule, is selected as a qualitative measure of system performance and is evaluated by simulation. The impact of the choice of the censoring threshold on the average detection error probability, under several values of channel estimation error, channel SNR, and sensor SNR, is studied. [ABSTRACT FROM PUBLISHER]

Physical Unclonable Functions (PUFs) are an alternative to conventional secure key storage in embedded devices. PUFs exploit unique sub-micron manufacturing variations in each device to generate characteristic responses. Each response is subject to noise, so a so called fuzzy embedder is required to use a PUF for reliable key reproduction. Index-Based Syndrome coding (IBS) is an information theoretically secure fuzzy embedder, introduced in 2010 [1]. This work derives a lower bound for the reliability of IBS-based fuzzy embedders, that depends on the characteristics of the PUF and the parameters of the fuzzy embedder. In addition, the channel capacity is applied as new criterion for fuzzy embedder evaluation. In this case, the channel capacity determines the maximum key size that can be embedded. The presented measure is complementary to security analysis and thus adds a new dimension for evaluating future encoding schemes for IBS-based fuzzy embedders. A case study demonstrates the practical impact of the contributions. [ABSTRACT FROM PUBLISHER]

This paper explores the balance between cooperation through relay nodes and aggregated interference generation in large decentralized wireless networks using decode-and-forward. The source nodes in the network are modeled using a marked Poisson process. We consider the case in which only a single randomly located relay is added to one source in the network and study the outage probability gains obtained. Then, using a simple model, we study the case in which all sources can potentially use their nearest neighbor from the set of inactive nodes as relays, leading to a mixed transmission scheme in which some users employ decode-and-forward and others employ direct transmission. The optimal relay activation probability for the second case is found, observing that in the small outage probability regime it exhibits a binary behavior, being zero or one. Comparing both scenarios we conclude that activating more relays rapidly reduces the gains observed when only one source can use a relay. We derive closed-form approximations to the upper bounds on the error probability, averaging over all node positions and fading gains realizations, to support our claims. [ABSTRACT FROM PUBLISHER]

We consider the bidirectional broadcast channel with common and confidential messages. We show that polar codes achieve the capacity of binary input symmetrical bidirectional broadcast channels with confidential messages, if one node's channel is a degraded version of the other node's channel. We also find a new bound on the cardinality of the auxiliary random variable in this setup. [ABSTRACT FROM PUBLISHER]

In this paper, we determine the performances of an Optical Code Division Multiple Access (OCDMA) based wireless transmission system for indoor healthcare monitoring application. We consider line of sight communication links between multiple emitters placed on monitored patients and a base station located at the environment ceiling. We first establish an analytical expression of error probability for fixed patient positions, considering On-Off Keying modulation and Optical Orthogonal Codes (OOC). After validation of the theoretical results, we then study the performance degradation because of patient mobility, in terms of outage probability. The impact of mobility is analyzed as a function of patient number, OOC length end environment dimensions. Thanks to our theoretical approach, we show that it is possible to assess the wireless OCDMA system performance for any quality of service. [ABSTRACT FROM PUBLISHER]

Cooperative systems are being widely investigated and error probability expressions for various network configurations have been obtained. Even though analytical models are accurate, they often lack tractability and do not shed much light on the interplay between channel conditions, network parameters and transceiver characteristics. This paper exploits a recently introduced technique, which uses signal-to-noise ratios to characterise the modulation and coding scheme of transceivers for Rayleigh fading channels. Based on this technique, which allows decoupling of error probability analysis and radio specifications, we derive conditions on the adopted transmission scheme to ensure that cooperation improves the outage probability of each user in decode-and-forward networks with statistically similar or dissimilar uplink channels. [ABSTRACT FROM PUBLISHER]

In analyses of the convolutional codes with soft decision Viterbi decoding, an upper bound approach was widely adopted to evaluate the error performance. The upper bound approach gives better estimation of error performance in high signal-to-noise-power ratio (SNR) condition, by contrast, it gives a poor result in low SNR. The exact bit error analyses of convolutional codes have been reported. Their method can derive exact error performance in low SNR. Besides, they employ an iterative calculation of probability density function (pdf) without considering truncation errors. The purpose of this paper is to extend their result to the error performance with truncation errors due to a finite path history. Furthermore, an application to the interference channels is demonstrated. [ABSTRACT FROM PUBLISHER]

In this paper, the combination of distributed Interleave-Division-Multiplexing-Space-Time Codes (IDM-STCs) with Orthogonal Frequency Division Multiplexing (OFDM) in two-hop relay systems applying Decode-and-Forward (DF) is investigated. In order to cope with erroneous decoding at the relays, a model to capture the decoding reliabilities of the relays is formulated and a method to incorporate these reliabilities in the iterative detection process at the destination is presented. In addition, different approaches to keep the required signaling overhead low are discussed and compared with each other. It is shown, that the proposed scheme achieves significant gains over the common DF detection scheme assuming perfect decoding at the relays. Even with only one bit signaling per frame and relay an improvement of 3.6 dB can be obtained in certain scenarios. [ABSTRACT FROM PUBLISHER]

Hyperspectral image is a substitution of more than a hundred images, called bands, of the same region. They are taken at juxtaposed frequencies. The reference image of the region is called Ground Truth map (GT). the problematic is how to find the good bands to classify the pixels of regions; because the bands can be not only redundant, but a source of confusion, and decreasing so the accuracy of classification. Some methods use Mutual Information (MI) and threshold, to select relevant bands. Recently theres an algorithm selection based on mutual information, using bandwidth rejection and a threshold to control and eliminate redundancy. The band top ranking the MI is selected, and if its neighbors have sensibly the same MI with the GT, they will be considered redundant and so discarded. This is the most inconvenient of this method, because this avoids the advantage of hyperspectral images∷ some precious information can be discarded. In this paper well make difference between useful and useless redundancy. A band contains useful redundancy if it contributes to decreasing error probability. According to this scheme, we introduce new algorithm using also mutual information, but it retains only the bands minimizing the error probability of classification. To control redundancy, we introduce a complementary threshold. So the good band candidate must contribute to decrease the last error probability augmented by the threshold. This process is a wrapper strategy; it gets high performance of classification accuracy but it is expensive than filter strategy. [ABSTRACT FROM PUBLISHER]

Recently the demand for high data rate has been increasing along with the need to connect many users to an access point (AP) or a base station (BS). In this paper, we propose a bit-interleaved coded multi-user multilevel modulation (MU-MLM) for orthogonal frequency division multiple access (OFDMA) systems. MU-MLM is multilevel modulation (MLM) incorporating multiple users at each modulated symbol. This allows each channel resource of OFDM system to be optimized with higher order modulation (HOM) as well as carry data to multiple users. At the receive side, the received signal is MMSE equalized and successive decoding is done until the level of MLM that is assigned to respective user is decoupled. The equalization at the receiver for the proposed system is far less complex as the same signal is transmitted to all the users. Simulation results show that the proposed system has better BER performance compared to conventional M-ary Quadrature amplitude modulation (M-QAM). The performance is further improved for HOM like 1024-QAM. [ABSTRACT FROM PUBLISHER]

It is shown that, for all prime powers q and all equation, then there exists an [n, k; q] code that is proper for error detection. [ABSTRACT FROM PUBLISHER]

Given an independent and identically distributed source X = {Xi}i=1∞ with finite Shannon entropy or differential entropy (as the case may be) H(X), the non-asymptotic equipartition property (NEP) with respect to H(X) is established, which characterizes, for any finite block length n, how close −1 over n ln p(X1X2…Xn) is to H(X) by determining the information spectrum of X1X2…Xn, i.e., the distribution of −1 over n ln p(X1X2…Xn). Non-asymptotic equipartition properties (with respect to conditional entropy, mutual information, and relative entropy) in a similar nature can also be established [3]. These non-asymptotic equipartition properties are instrumental to the development of non-asymptotic coding (including both source and channel coding) results in information theory in the same way as the asymptotic equipartition property to all asymptotic coding theorems established so far in information theory. As an example, the NEP with respect to H(X) is used to establish a non-asymptotic fixed rate source coding theorem, which reveals, for any finite block length n, a complete picture about the tradeoff between the minimum rate of fixed rate coding of X1…Xn and error probability when the error probability is a constant, or goes to 0 with block length n at a sub-polynomial n−α, 0 &#60; α &#60; 1, polynomial n−α, α ≥ 1, or sub-exponential ℯ−nα, 0 &#60; α &#60; 1, speed. In particular, it is shown that for any finite block length n, the minimum rate (in nats per symbol) of fixed rate coding of X1X2…Xn with error probability equation is equation, where α > 0 and σH2(X) = E[−lnp(X1)]2 − H2(X) is the information variance of X. With the help of the NEP with respect to other information quantities, non-asymptotic channel coding theorems of similar nature will be established in a separate paper. [ABSTRACT FROM PUBLISHER]

A novel code construction based on spatially coupled low-density parity-check (SC-LDPC) code chains is presented. The proposed code ensembles are described by graphs in which individual SC-LDPC code chains of various lengths serve as edges. We demonstrate that connecting several appropriately chosen SC-LDPC code chains results in improved iterative decoding thresholds compared to those of a single coupled chain in addition to reducing the decoding complexity required to achieve a specific bit error probability. [ABSTRACT FROM PUBLISHER]

By allowing the occurrence of infrequent timing errors and correcting them with rollback mechanisms, the so-called timing speculation (TS) technique can significantly improve circuit energy-efficiency and hence has become one of the most promising solutions to mitigate the ever-increasing variation effects in nanometer technologies. As timing error recovery incurs non-trivial performance/energy overhead, it is important to reshape the delay distribution of critical paths in timing-speculated circuits to minimize their timing error rates. Most existing TS optimization techniques achieve this objective with post-synthesis techniques such as gate sizing or body biasing. In this work, we propose to conduct logic synthesis for timing-speculated circuits from the ground up. Being able to manipulate circuit structures during logic optimization, the proposed solution is able to dramatically reduce circuit timing error rates and hence improve its throughput, as demonstrated with experimental results on various benchmark circuits. [ABSTRACT FROM PUBLISHER]

This paper focuses on energy efficient transmission in Amplify-and-Forward (AF) relay networks with bidirectional asymmetric traffic. A joint relay selection and power allocation scheme is designed to minimize the energy consumed per bit transmitted for both one-way and two-way relay networks. Through theoretical analysis, close-form solutions for energy efficient power allocation are derived at each relay. Then the direct transmission mode or the relay consuming the least energy is chosen by the sources according to the feedback of each relay. Simulation results present the considerable energy saving ability of the proposed scheme compared with the extended best worse channel relay selection and uniform power allocation (PA) schemes. [ABSTRACT FROM PUBLISHER]

Spectrum sensing is considered as the first and main step for cognitive radio systems to achieve an efficient use of spectrum. Cooperation and clustering among cognitive radio users are two techniques that can be employed with spectrum sensing in order to improve the sensing performance by reducing miss-detection and false alarm. In this paper, within the framework of a clustering-based cooperative spectrum sensing scheme, we study the effect of errors in transmitting the local decisions from the secondary users to the cluster heads (or the fusion center), while considering non-identical channel conditions between the secondary users. Closed-form expressions for the global probabilities of detection and false alarm at the cluster head are derived. [ABSTRACT FROM PUBLISHER]

In this paper, single amplify and forward (AF) relay is placed between the source and the destination in space shift keying (SSK) multiple-input single output (MISO) system. In SSK, transmit-antenna indices form a spatial constellation diagram where each group of base two logarithm of the input data bits are mapped to one spatial constellation point. Hence, at each time instant, only single transmit antenna is active, which transmits certain energy that contains no data symbol, and all other antennas are off. The receiver, with single receive antenna, decodes the received signal from the single antenna AF relay and estimates the index of the active transmit-antenna to retrieve the transmitted information bits. Closed-form bit error ratio (BER) is derived for the considered system in correlated and uncorrelated channels assuming a transmitter with two transmit antennas. The analytical framework is generalized for an arbitrary number of transmit antennas and a tight upper bound on the BER performance is derived. Additionally, asymptotic analysis are carried out to investigate the effect of the different system parameters on the overall system performance. The analytical results are validated through Monte-Carlo simulation results. [ABSTRACT FROM PUBLISHER]

Incremental opportunistic relaying (IOR) has been proposed to increase the spectral efficiency of the two-phase cooperative transmissions by exploiting limited feedback from the destination node. Specifically, the relaying process is activated only if the source-destination channel is of insufficient quality. In this case, the feedback instructs the best relay to forward the source message to the destination in order to exploit the spatial diversity. In this work, we analyze the effect of feedback delay on the performance of IOR with decode-and-forward strategy. Particularly, we derive an exact expression for the average symbol error probability (SEP) of IOR with feedback delay over independent but not necessarily identically distributed Rayleigh fading channels. An approximate but tight closed-form expression for the SEP is also provided. Finally, we perform Monte Carlo simulations to verify the analytical results. The results show that IOR is robust to the feedback delay at sufficiently high signal-to-noise ratio. [ABSTRACT FROM PUBLISHER]