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Oil-paper insulation is the key insulation structure of the transformers, whose aging condition is closely related to the operations of the equipment. The degree of polymerization (DP) is the direct parameter characterizing the aging condition of oil-paper insulation. Recently, the near infrared spectroscopy (NIRS) measurement powered by quantitative analysis is used to evaluate DP of the insulating papers mainly. While the applications of NIRS for DP evaluation is constrained because the present spectral quantitative analysis method is not accurate and stable enough, especially for onsite tests. In this paper, we propose a Gaussian process regression (GPR) method to predict DP of the oil- paper insulation in laboratory as well as in field. Firstly, the basic principles of GPR algorithm are illustrated. A GPR model for DP prediction is established based on the spectra of differently aged insulating paper samples which are prepared in laboratory. The GPR model show a high prediction accuracy both for training set and testing set. The established GPR model is finally applied on the DP prediction of insulating papers originating from a de-tanked transformer. The accurate predicted DP and the reliable aging assessment results indicate that the established model can be implemented on site.

Oil-paper insulation is an important component of the oil-immersed power transformer, and its insulation life is directly related to the operating life of the transformer. Therefore, it is particularly important to accurately assess the life of the oil-paper insulation system. In this paper, aging insulation paper samples with different mechanical stresses were prepared in an aging vibration chamber under laboratory conditions, and the activation energy under the synergistic machine-thermal action was obtained using the translation factor. The Arrhenius equation was then combined with the Ekenstam equation to derive an equation that can accurately determine the degree of polymerization of the oil-paper insulation system. It is proved that this equation can predict the degree of polymerization of the paper under the synergistic action of machine and heat, and can provide theoretical support for the evaluation of paper life.

In this paper, we obtain samples of thermal aging transformer insulation paper at 6 time points through an accelerated thermal aging test that simulates the actual operating state of the transformer. The Raman spectroscopy diagnosis model of transformer insulating paper aging is proposed. The model combines an autoencoder and a linear discriminant analysis algorithm to extract the characteristics of the Raman spectrum, and uses a Naive Bayes classification method to divide the aging stage of the insulating paper. Through the Raman spectroscopy diagnosis model of transformer insulation paper aging designed in this paper, the Raman spectroscopy characteristic quantity extracted by the AE-LDA method can effectively reflect the aging characteristic information of the insulating paper, and the Naive Bayes classification algorithm is used to predict. Research shows that the model has a high predictive accuracy for the assessment of the aging state of insulating paper, and can effectively diagnose the aging state of transformer oil-paper insulation. The Raman spectroscopy used in the diagnosis of the aging of insulating paper has good aging discrimination ability and good application prospects, and provides a new idea for the diagnosis of the aging state of transformer oil-paper insulation.

In this paper, a method based on Raman spectroscopy to diagnose the aging degree of oil-paper insulation is discussed. According to IEEE guidelines, oil-paper insulation samples were prepared in the laboratory, and the degree of polymerization values of the samples were measured to obtain the exact aging states. Raman detections of the samples were carried out based on the Raman experimental platform. T-S fuzzy neural network was used to analyze the Raman spectrum data of insulating oil. By using the experimental data to train the diagnosis model, constantly modifying the membership function, and mining the internal mathematical relationship between the Raman spectrum characteristics of oil paper insulation and the degree of polymerization of insulating paper, this paper managed to use the Raman spectrum data of insulating oil to predict the aging degree of oil paper insulation. Finally, the deviations between the predicted and the measured degree of polymerization values of the five test samples in this experiment are both less than 150.

In this paper, we study the state-dependent Gaussian wiretap channel with action encoder and noncausal state at the transmitter, which is also called the action-dependent dirty paper wiretap channel. Two lower bounds on the secrecy capacity of this model are provided, and we find that the two bounds have their advantages and disadvantages, i.e., none of the two always performs better than the other. In addition, we find that taking action on the state helps to increase the achievable secrecy rate of the dirty paper wiretap channel.

The dirty paper wiretap channel, also referred to as the Gaussian wiretap channel with noncausal channel state at the transmitter, plays an important role in wireless physical layer security. In this paper, the dirty paper wiretap channel is revisited by considering actions on the channel state, i.e., the transmitter generates an action sequence that affects the formation of the channel state. Lower and upper bounds on the secrecy capacity of this model are proposed, and numerical results indicate that the actions on the state help to increase the achievable secrecy rate of the dirty paper wiretap channel. The study of this paper offers a new option for enhancing the secrecy rates of the state-dependent wiretap channel models.

The problem of joint information transmission and input signalling estimation over a state-dependent channel is considered. The general single-letter upper and lower bounds of the optimal capacity-distortion trade-offs are provided. For the Gaussian dirty paper channel, we calculate the bounds by choosing parameters carefully, and obtain a computable form eventually. In such a way, we obtain a complete characterization for this problem setting.

Rapid identification of aging state of oil-paper insulation is of great significance to the operation safety of power transformers. Raman spectroscopy can rapidly analyze the aging characteristic information dissolved in oil, and it is an effective means for the aging diagnosis of oil-paper insulation. In this paper, Multiple screening KNN Algorithms for Raman spectroscopy analysis of aging oil-paper insulation samples is presented. A large number of aging oil samples were obtained by accelerated thermal aging test. According to the aging days, the samples were divided into 12 categories, and 230 Raman spectra were obtained by Raman spectroscopy. The KNN algorithm is used for classification and regression of Raman Spectra of test samples by Pearson correlation coefficient. Then, based on the traditional KNN algorithm, a multi-screening KNN is proposed according to the actual situation of the aging process of insulating oil Raman spectrum. The prediction of Multiple screening KNN Algorithms accuracy of classification reaches 87.92%, and the RMSE of regression reached 54.28.

In this paper we propose to implements blockchain technology for Internet of Things (IoT) networks that use Practical Byzantine Fault Tolerance (PBFT) consensus algorithm. To eliminate the reliance on a single leader and improve performance, we propose to allow multiple leaders to propose request batches independently and, possibly, concurrently, by using different overlay networks. Nodes participate in parallel consensus rounds without contention, and they only contend with others to reserve the next available spot for the atomic insertion of a new transaction batch or block into the replicated blockchain ledger. We develop an analytical model for the multiple leader PBFT ordering service by using a Discrete-time Markov chain. Our evaluations show that our model outperforms the original multiple entry point PBFT protocol in a wide range of parameter values, and that it scales well with the number of orderer nodes in the PBFT committee and block arrival rate.

People re-identification is a fundamental stage in video surveillance systems. This stage is used for determining the labels of the people’s images usually based on their visual similarities. The appearance salience caused by wearing the clothes and carrying objects, with specific colors can be used for improving the performance of re-identification systems. To address the mentioned point, in this paper, we propose a color-based re-ranking process. In the proposed approach first, the input images are semantically segmented as: person’s body, possible carried objects, and background. Then the most frequent colors of person’s body and possible carried objects are used to re-order the ranked results obtained from two commonly used re-identification approaches i.e., Gaussian of Gaussian (GOG) and Hierarchical Gaussian Descriptors (HGDs). Experimental results on various people re-identification datasets show that our proposed re-ranking approach can improve the performance of re-identification systems.

International audience; Reconfigurable intelligent surfaces (RISs) represent a new technology that can shape the radio wave propagation and thus offers a great variety of possible performance and implementation gains. Motivated by this, we investigate the achievable sum-rate optimization in a broadcast channel (BC) that is equipped with an RIS. We exploit the well-known duality between the Gaussian multiple-input multiple-output (MIMO) BC and multiple-access channel (MAC) to derive an alternating optimization (AO) algorithm which jointly optimizes the users’ covariance matrices and the RIS phase shifts in the dual MAC. The optimal users’ covariance matrices are obtained by a dual decomposition method in which each iteration is solved in closed-form. The optimal RIS phase shifts are also computed using a derived closed-form expression. Furthermore, we present a computational complexity analysis for the proposed AO algorithm. Simulation results show that the proposed AO algorithm can provide significant achievable sum-rate gains in a BC.

We explore the power of parallelism in a stochastic search for global optimum in high-dimensional optimization problems. This search, that often navigates a large solution space through a Markov-Chain Monte Carlo (MCMC) process, needs to make stochastic decisions at every step and needs to escape from local optima. Through parallelism, we are able to survey an entire neighbourhood (all states with Hamming distance of 1) to make efficient moves, use multiple replicas at different temperatures, such as in parallel tempering, or deploy a population of replicas at the same temperature. Once combined, these methods of parallelism can yield 100x to 10,000x speedups.

In this paper, we present a plug and play Rock-Paper-Scissors game set that utilizes CNN-based static hand gesture recognition and a Markov chain-based bot. Each game round, the camera output is fed to the neural network and the hand gesture result is compared to the current Markov chain state. We utilize a CNN trained with a dataset containing rock-paperscissors hand gestures and unwanted inputs, and a multi-state Markov chain. Automated tests confirm the bot prediction capabilities and practical tests verify the precision of static hand gesture recognition. Tests against a verification dataset reveal a recognition accuracy of 97.4%.

In order to finding more perfect dielectric response function, the mixed polarization equivalent circuit model is proposed by combining interface polarization equivalent circuit model in oil paper insulation, which fit the actual relaxation process of oil paper insulation system. At the same time, to resolve complex computational problems of parameters identification quickly, the method of parameters identification for mixed polarization circuit model is presented based on particle swarm optimization algorithm. Finally, through the analysis and comparison of examples, confirmed that the mixed polarization circuit model is correct and has higher accuracy compared to the Debye equivalent circuit model, and can more truly reflect the relaxation process of oil paper insulation system.

Thermal aging of HVDC Mass Impregnated Polypropylene Laminated Paper (MI-PPLP) cable could reduce the dielectric strength. And degradation of the physical and chemical properties of MI-PPLP could be caused by partial discharge in voids created by cavitation phenomenon. If void discharge is maintained, electrical aging is accelerated at the interface between air void and MI-PPLP, and ultimately dielectric breakdown occurs. There are several reports on the dielectric breakdown and partial discharge characteristics for insulation diagnosis of HVDC MI-PPLP cable. However, studies on the dielectric breakdown and partial discharge characteristics of HVDC MI-PPLP cables considering the thermal aging are insufficient. Therefore, in this paper, breakdown voltage (BDV) and partial discharge inception voltage (PDIV) characteristics are analyzed under the influence of the thermal aging of void defects. since it takes a lot of time to evaluate the insulation performance of MI-PPLP due to thermal aging under normal operating conditions, the thermal aging process was shortened through accelerated aging at 120°C. For reliable experiments, the equivalent lifetime between accelerated aging and normal operating conditions was suggested using the Arrhenius model. Since the Arrhenius model shows the reaction rate according to the activation energy of the specimen, the equivalent lifetime must be derived from the activation energy. The activation energy can be derived by applying the Kissinger method to thermos gravimetric analysis (TGA). From the experimental results, As the thermal aging of MI-PPLP proceeded, decrease in BDV is more severe than PDIV due to the increased Permittivity. Consequently, it is considered that relation between BDV and PDIV characteristics due to thermal aging can be estimated based on the equivalent lifetime obtained through the Arrhenius model.

Paper illustrates the process of topic modeling and text classification. Specifically, the dataset used is a corpus consisting of scientific publications published by Neural Information Systems Processing Conference. Topic modeling itself is performed using Latent Dirichlet Allocation model. It is followed by optimization of a number of topics on the basis of topic coherence, a quality measure of human interpretability. Results of topic modeling are used for labeling data prior to text classification. Labels are determined based on the distribution of assigned papers' topics over time. Specifically, peak changes used for differentiating between time periods dominated by specific topics are calculated as a Kullback-Leibler divergence. Finally, transforming data into the feature vectors, several different text classification approaches are evaluated. As observed, the greatest accuracy score is recorded for the use of extreme gradient boosting classifier being 77.1%.

The conventional fixed-coefficient linear modeling of the rectifiers in energy harvesting devices can lead to inaccurate analysis and design of far-field radio-frequency wireless power transfer systems. The said inaccuracy exists even in the square-law operation region of the rectifiers. In this paper, a new Bessel-based tight lower-bound formula for the output current in energy harvesters [1] is applied for multi-band MIMO (multiple-input multiple-output) wireless power transfer, with the purpose of finding the optimal transmit waveform for maximizing the harvested energy. Comparisons with the conventional fixed-coefficient rectifier model are provided, and show the superiority of the proposed Bessel-based model and design.

In order to assess the moisture content of insulating pressboard in oil-immersed transformer, and thus providing reliable guidance for insulation condition and life estimation of oil-immersed transformer, in this paper, we made four groups of oil-paper insulation samples with different moisture content under laboratory conditions and studied the relationship between pressboard and moisture content by using polarization and depolarization current (PDC) technique. The experiment result shows that PDC curve is very sensitive to the change of moisture content, and the change of moisture content mainly affects the tail of depolarization current curve; the extended Debye model parameters can be obtained from depolarization current curve, and as the moisture content increases the number of branches in Debye model increases, the largest time constant becomes large; the peak of time domain spectroscopy turn up at 1000s., the time constant branch which is longer than 1000s presents the pressboard branches of Debye model; the feature quantity Q paper can show the internal polarization of insulating paper and has a linear fitting relationship with moisture content, so Q paper can be used to assess the moisture content of insulating pressboard.

Micro aerial vehicle (MAV) gradually gains plentiful attention in recent years. However, it is still a full challenge to design MAVs with high aerodynamic performance because aerodynamic efficiency of wings deteriorates sharply at low Reynolds numbers. Under this circumstance, we focus on one unconventional configuration with annular wing, which can be folded from a square paper. The annular paperplane configuration is described with geometric parameters, and the longitudinal and lateral aerodynamic characteristics are studied with RANS method.

This study proposes Raman spectroscopy of tear fluid with paper substrates for on-site therapeutic drug monitoring(TDM). In this method, the paper substrates are used for tear sample collection and measurement. The use of paper offers a minimally-invasive, simple, and inexpensive method for therapeutic drug monitoring. To demonstrate the usability of the paper substrates for this purpose, we measured Raman spectra of samples containing therapeutic drug and glucose with a filter paper. Experimental results show the ability to detect Raman signals from the samples absorbed on the paper substrate.

Uncertainty quantification techniques have been widely used to model devices, circuits, and systems with fabrication process variations. However, most existing techniques assume that all random parameters are mutually independent or Gaussian correlated, which is rarely true in practice. How to handle non-Gaussian correlated random parameters is a fundamental and long-standing challenge. In this paper, we review existing techniques and point out their limitations. Then, we summarize our recent work to address the theoretical and computational challenges caused by non-Gaussian correlations.

In this paper, we address the problem of finding sequence motifs in substrate proteins specific to E3 ubiquitin ligases (E3s). We formulated a posterior probability distribution of sites by designing a likelihood function based on amino acid indexing and a prior distribution based on the disorderness of protein sequences. These designs are derived from known characteristics of E3 binding sites in substrate proteins. Then, we devise a collapsed Gibbs sampling algorithm for the posterior probability distribution called DegSampler. We performed computational experiments using 36 sets of substrate proteins specific to E3s and compared the performance of DegSampler with those of popular motif finders, MEME and GLAM2. The results showed that DegSampler was superior to the others in finding E3 binding motifs. Thus, DegSampler is a promising tool for finding E3 motifs in substrate proteins.

This paper discuss drug concentration measurement based on Raman spectroscopy of tear fluids with paper substrates for on-site therapeutic drug monitoring (TDM). We focus on tear fluids as alternative specimens to blood for minimally-invasive TDM. By using paper substrates, specimen collection and measurement based on surface enhanced Raman spectroscopy will be performed easily and inexpensively. In experiment, we fabricated paper-based substrate for surface enhanced Raman spectroscopy (SERS) of tear fluids and evaluated its surface. Scanning electron microscope images of them showed that gold nano-rods were adsorbed on the surface uniformly. This result implies that analysis of tear fluids with paper substrates would be realized with high sensitivity by SERS.

In this paper we study the effect of partial channel state information (CSI) on the performance of dirty paper coding (DPC) schemes. We derive a novel lower bound that shows that the effect of the CSI is upper bounded by the effect of an additive white Gaussian noise with an appropriate variance. The bound is proved using a constructive proof that shows that the predicted rates are achievable using high dimensional lattice modulo precoding schemes. Simulation results demonstrate the usefulness of the bound. The derived bound is useful for the characterization of the interference mitigation performance in partial CSI scenarios such as FDD networks with finite rate feedback, uplink downlink capacity balancing in cooperative cellular networks, etc'.

As computational needs increase in relation to the growing fields of Internet of Things and Deep Learning, energy-efficient, computational units are needed to bypass DSP units within Von Neumann architectures. A charge-mode vector matrix multiplier (VMM) with compute-in memory capabilities was fabricated in the Global Foundries 55nm LP process. The array is comprised of a 156 row by 512 column crossbar where each row computes a 512 element binary dot product in the charge domain. This normalized analog multiply and accumulate (MAC) is carried out by charge-injection devices who compute a 1-bit multiplication in the charge domain. Preliminary test results show successful, linear output computation in the analog domain to various input vectors that are both digital and multi-level analog. The 156 × 512 compute-in memory, CID array has been simulated to achieve an efficiency of 1.8 TOPs per mW.

In this paper, we characterize the capacity regions of the Gaussian doubly dirty two-way channel (DD-TWC) in the presence of noise-dependent interference as well as input-dependent interference, and thereby we quantify the impact of such dependencies on the capacity region of the Gaussian DD-TWC. We also show that for the Gaussian DD-TWC with noise/input-dependent interference, adaptation (the use of formerly received signals in encoding process) is useless from a capacity point of view. The above-mentioned claims are proved by obtaining a capacity outer bound in the adaptive mode which is coincided with capacity inner bound derived in the non-adaptive mode.

A capability of tracking and follows the target object on the water surface is an essential measurement in the control system for a Unmanned Surface Vehicle (USV). Path following algorithm usually used to describe the target, compute in the controller and minimize as well as to zero the distance between USV; and the angle between the vessel speed and the tangent to the path. USV needs to follow a time-parameterized reference curve are defined as a trajectory tracking. This paper gives an attention in reviewing a few common path following as well as path tracking techniques used in the design of USV where there is no predefined position will be declared in the control system. In particular, this paper is focused on a motion control approaches developed using USV by reviewing forty journals for last ten years. Based on the reviews, a line-of-sight (LOS) technique is a frequently implemented in the USV control system than another method such as constant-bearing guidance, Kalman filtering, PID guidance, Lyapunov-based guidance, pure-pursuit (PP) guidance, motion goal prediction, back stepping method and Jacobian task priority. As the conclusion, various types of mathematical computation are introduced in the USV control system is customizes with the requirement based on the situation needed will make this autonomous vehicle more advanced.

In the past, partial discharge was considered as a completely random process, and various statistical spectra such as phase resolved partial discharge (PRPD) were constructed, but the accuracy still needs to be further improved. The chaos theory is introduced to research the development of partial-discharge defects of oil-paper insulation in transformer. The sphere-plate partial discharge model was constructed in the laboratory. And the data of the pulse discharge during the development of the pressboard from the initial discharge to the breakdown was obtained by the constant voltage method under six voltage levels. By constructing the discharge time series, the chaotic attractors are reconstructed in the phase space. And all the attractors of the samples under the six voltage levels satisfy the largest Lyapunov exponent λ 1 >0, the correlation dimension D is the fraction and the Kolmogorov entropy K 2 >0, indicating that the partial discharge is a deterministic chaotic process. It provides new research ideas for the diagnosis and prediction of the aging and the development of electrical branches for oil-paper insulation.

The insulation diagnosis method based on frequency domain dielectric spectrum is widely used in field test because of its nondestructive testing, rich insulation information and so on. FDS measurement results are easy to be affected by many factors. However, interpretation on the dielectric properties of oil paper insulation with moisture content, impurity ion concentration influence mechanism of the current research is not very ideal, so it is necessary to determine more appropriate and effective dielectric response simulation and experimental analysis of characteristics. In addition, moisture content (m.c.) is an extremely important factor which can determine the insulation state of Oil-immersed paper. Therefore, the evaluation of moisture content of oil-immersed paper has obvious significance. In this paper, based on the experimental results, the extended Debye model parameters of the field transformer are obtained. Then, the influence of the insulation resistance value in the Debye model on the FDS curve is simulated by MATLAB modeling. The simulation and experimental verification show that the regularity of the change of the FDS conductance process is obviously different from the moisture content influenced by the impurity ions. The impurity ions mainly affect the low frequency section of the imaginary part of the complex capacitor. A non-linear phenomenon in dielectric response with different moisture contents under different is observed. We found that the non-linear phenomenon has relationship with the hindrance effect of cellulose (m.c.

Recycled paper is extensively used worldwide. In the last decades its market has expanded considerably. The increasing use of recycled paper in papermaking has led to the production of paper containing several types of impurities. Consequently, wastepaper mills are forced to implement quality control schemes for evaluating the incoming wastepaper stock, thus guarantying the specifications of the final product. The main objective of this work is to present a fast and reliable system for identifying different paper types. Therefore, undesirable paper types can be refused, improving the performance of the paper machine and the final quality of the paper manufactured. For this purpose two fast techniques, i.e., Fourier transform mid-infrared (FTIR) and reflectance near-infrared (*IR) were applied to acquire the infrared spectra of the paper samples. *ext, four processing multivariate methods, i.e., principal component analysis (PCA), canonical variate analysis (CVA), extended canonical variate analysis (ECVA) and support vector machines (SVM) were employed in the feature extraction –or dimension reduction– stage. Afterwards, the k nearest neighbors algorithm (k**) was used in the classification phase. Experimental results show the usefulness of the proposed methodology and the potential of both FTIR and *IR spectroscopic methods. Using the FTIR spectrum in association with SVM and k** the system achieved maximum classification accuracy of 100%, whereas using the *IR spectrum in association with ECVA or SVM and k** the system achieved maximum classification accuracy of 96.4%

In an academic paper search to confirm the originality of a user's research, it is important that the search returns comprehensive results relevant to the user's information need. To achieve comprehensive search results, users often relax initially restrictive search formula by adding synonyms and expressions similar to the search words with operator OR, and/or replacing AND with OR operations. However, it is difficult to anticipate all the terms that authors of relevant papers might have used. In addition, the replacement of AND with OR in search phrases can return a large number of unrelated papers. To overcome these issues, we propose a research paper search method based on topic analysis, which uses Boolean search based on the topics assigned to the search words in the search formula and the abstracts that contain any search word. Our method considers synonyms and expressions similar to the search words, which a user might not anticipate, while limiting the number of papers unrelated to the information need in the search result. To investigate the effectiveness of our method, we conducted experiments using the NTCIR-1 and 2 datasets, and confirmed that our method shows a reduction effect on unrelated papers, while maintaining high coverage.

Frequency Domain Spectroscopy (FDS) technique is widely used to perform diagnosis of oil-paper insulation. Results reported in this paper suggest that it is imperative to obtain charge free insulation for FDS measurement in order to obtain reliable insulation diagnosis result. It is practically difficult to ensure such condition for practical transformer as it often contains trapped charge. This means the results of FDS must be studied along with the effect of charge for better interpretation of the physical condition of oil-paper insulation under test. This paper presents a comparative study of FDS data obtained from a charged and uncharged oil-paper insulation sample. FDS measurement of uncharged insulation sample is performed and tanδ profile is measured first. Thereafter, different amount of charge is introduced in the insulation sample by applying high dc voltage across the sample for different time intervals followed by FDS measurement of the charged sample. It is observed that presence of charge affects the frequency domain dielectric response of the sample non-linearly. Being a linear model, this non-linear behavior of oil-paper insulation in presence of charge cannot be addressed by popular insulation model like Conventional Debye Model (CDM).

Polarization Depolarization Current (PDC) measurement is widely used by utilities for condition assessment of oil-paper insulation. Conventional Debye Model (CDM) is an accepted technique used to analyze PDC data. Highest magnitude of Zero (Zi) of the Transfer Function obtained from the CDM model is reported to maintain a well-defined relation with moisture content (%pm) present in the paper. However, the influence of measurement temperature on the said relationship between Zi and %pm is yet to be investigated. It is known that %pm as well as the polarization current profile are influenced by measurement temperature. As PDC measurement is an offline technique, the measurement is performed post shut-down after the unit reaches thermal equilibrium with ambient. Hence, the result does not follow the system behavior when it is in operation. To estimate the condition of the system during operation, it is required to obtain the performance parameters at different temperatures other than the temperature at which the measurement is done. In the present work, multiple samples are prepared in the laboratory and PDC measurement is carried out at three different temperatures. In the present study influence of measurement temperature on the relation (between Z 1 and %pm) is investigated.

Conventional Debye Model is commonly used for analysis of dielectric response function evaluated from Polarization and Depolarization Current data. The same Polarization current profile when fitted to obtain insulation model, may result in different number of branches depending on curve fitting parameter. Zero of Transfer Function (evaluated using insulation Model parameters) having highest magnitude can be used to obtain performance parameters like paper-moisture and dissipation factor. In this present work, polarization current data from laboratory sample is measured at two different temperatures. This is followed by formulation of Conventional Debye Model parameters from each measurement. The two resulting insulation model structures are not identical in terms of number of branches and parameters therein as branch parameters depend on curve fitting. This paper investigates the influence of varying branch parameters of Conventional Debye Model on the values of performance parameters that are evaluated using Zero of insulation model Transfer Function.

PDC measurement and analysis is one of widely used tool for reliable diagnosis of power transformer insulation. In different reported methods of analysis it is considered that polarization current is composed of the current due to dipole movement and conduction current. Similarly the depolarization current is assumed to be composed of relaxation of dipoles. However when the dc conduction effect is removed from polarization current it is found the resulting current is not similar to the measured depolarization current. This deviation in both the currents show the presence of nonlinearity in the system. This nonlinearity arises due to migration of trapped charges that reside at the interfacial region of oil-paper insulation. The present paper shows the effect of such free charge on some important performance parameters like paper moisture and zero of Transfer Function of Classical Debye Model.

Recently there has been a lot of success in using the deterministic approach to provide approximate characterization of Gaussian network capacity. In this paper, we take a deterministic view and revisit the problem of wiretap channel with side information. A precise characterization of the secrecy capacity is obtained for a linear deterministic model, which naturally suggests a coding scheme which we show to achieve the secrecy capacity of the degraded Gaussian model (dubbed as "secret writing on dirty paper") to within half a bit., Removed the section on writing on fading paper; improved the gap result from $(1/2)\log3$ bits to half a bit; added a section on secret-key agreement via dirty-paper coding; revised version submitted to the IEEE Transaction on Information Theory

The aim of this research is to classify the front side (observe) and back side (reserve) of Myanmar currencies (kyats) in three denominations. The system consists of binary image conversion, noise removal, feature extraction, and recognition. Zernike moment is used for feature extraction. The features from the top left, top right, bottom left and bottom right of the currency are extracted. The classification of the correct currency using the k -nearest neighbor algorithm based on the data set generated by Zernike Moment. The accuracy is measured based on the confusion matrix. The experimental results suggested that the approach is sufficiently effective and efficient in classifying the paper currencies.

This paper presents a non-wide-sense stationary uncorrelated scattering (non-WSSUS) model which takes accurately into account that the Doppler frequencies and propagation delays vary with time if the mobile station (MS) moves. Another feature of the proposed channel model is that the MS can change its velocity along the route. The result is that the Doppler spread and the delay spread deviate from their initial values with increasing time. This effect motivates the definition of quasi-stationary intervals. The lengths of these intervals will be analysed in terms of the velocity parameters. Our analysis shows that real- world channels can be quasi-stationary but not wide-sense stationary (WSS), neither in the time domain nor in the frequency domain. This implies that the generally accepted WSS and WSSUS assumptions are not fulfilled in practice, even not if the travelling distance is short.

The capacity region of the Gaussian interference channel with two source-destination pairs where the sources can cooperate is not known. Prabhakaran and Viswanath showed that the sum-rate capacity can be achieved to within 19 bits/s/Hz by using a combination of superposition coding and zero-forcing. This paper only focuses on the symmetric capacity, i.e., the maximum equal rate point that the two sources can simultaneously achieve in a Gaussian interference channel with symmetric channel gains, in the strong cooperation regime, i.e., when the cooperation link is stronger than either the direct link or the interference link. In this setting, it is showed that the “binning+superposition” achievable scheme of Yang and Tuninetti, implemented with Gaussian codebooks and Dirty Paper Coding, achieves the symmetric capacity to within 2 bits/s/Hz-thereby considerably reducing the previously known gap. The extension of this gap-result to other regimes is also discussed.

Boolean Satisfiability (SAT), the first problem proven to be NP-complete, is intractable on digital computers based on the von Neumann architecture. An efficient SAT solver can benefit many applications such as artificial intelligence, circuit design, and functional verification. Recently, a SAT solver approach based on a deterministic, continuous-time dynamical system (CTDS) was introduced [1]. This approach shows polynomial analog time-complexity on even the hardest k-SAT (k ≥ 3) problem instances, but at an energy cost dependent on exponentially growing auxiliary variables. This paper reports a novel analog hardware SAT solver, AC-SAT, implementing the CTDS via incorporating novel, analog circuit design ideas. AC-SAT is intended to be used as a co-processor and is programmable for handling different problem specifications. Furthermore, with its modular design, AC-SAT can be readily extended to solve larger size problems. SPICE simulation results show that AC-SAT can indeed solve the SAT problems, and it has speedup factors of ∼104 on even the hardest 3-SAT problems, when compared with a state-of-the-art SAT solver on digital computers.

This paper studies dirty-paper coding in a Gaussian broadcast channel with two receivers. It finds that an approximate version of dirty-paper coding using low-density lattices can be implemented with a complexity that is polynomial-time on average in the block length. The main difference between this paper and prior work is that a non-binary LDPC-based lattice codebook is used for each user, and one codebook is aligned with the other. The low-density nature enables tractable encoding and decoding algorithms, and the alignment gives structure to the overall signal transmitted and it enables us to perform the encoding and decoding efficiently.1

The superior shaping performance of low-density generation matrix (LDGM) codes makes them important in the design of capacity-approaching dirty paper coding (DPC) schemes. One possible LDGM-based DPC scheme is the nested LDGM-LDPC code proposed by Wainwright and Martinian, which has been shown to be capacity-achieving under optimal encoding and decoding. In this paper, considering the Gaussian DPC problem limited to a binary alphabet, we propose practical encoding and decoding algorithms for the nested LDGM-LDPC code utilizing ideas from the fast LDPC encoding algorithm to satisfy the parity constraints, and optimize the degree distributions of the code through density evolution. Simulation results show that the proposed scheme can indeed closely approach the alphabet-constrained DPC capacity.

Highly exfoliated graphite have been prepared from fluorinated graphite intercalation compounds of various flake sizes and stably dispersed in dimethylformamide. Further, we have processed the colloid into thin films or paper-like materials. The dispersion and films have been characterized by a set of physico-chemical methods including UV/vis, Raman and IR spectroscopies, X-ray diffraction (XRD), scanning electron microcopy (SEM) and dynamic and electrophoretic light scattering (DLS/ELS) techniques. The studies have shown that the use of the special type of expanded graphite allowed to reach higher concentrations than with natural graphite or conventional expanded graphites. Graphene plates in colloid have larger lateral sizes reaching several micrometers that is superior comparing to other methods like graphite oxide reduction.

The paper describes an approach to fabricate large area Graphene (Gr)/MoS 2 on paper using simple, cost effective solution processed hydrothermal method. Gr was deposited on paper using dip coating method followed by hydrothermal growth of 2D MoS 2 on Gr. Raman analysis confirmed the growth of few layer MoS2. IV characteristic of MoS 2 , MoS2/Gr revealed higher conductivity for Gr/MoS 2 . Under illumination 31.84 % and 55.33 % decrease in resistance was observed for MoS 2 and Gr/MoS2 based devices respectively indicating that Gr/MoS 2 based devices are more sensitive compared to MoS2. Successful fabrication of flexible paper based Gr/MoS 2 photodetector is a step ahead in large area, low cost electronic applications.

A paper-based electromechanical system (PB-EMS) driven by means of the Lorentz force excitation method is introduced in this work. Such a system consists of a paper-based cantilever beam that is fabricated using conventional printer paper, printable electronics, and standard cutting tools. The results show the feasibility to develop PB-EMS using the Lorentz force actuation principle. In addition, the influence of the driven current on the dynamic response of the PB-EMS is analyzed. A softening effect is identified when increasing the magnitude of the excitation current. This softening effect is evaluated using a lumped model. The spring constant as a function of the excitation current exhibits a linear relationship. Moreover, the frequency response of the system is experimentally studied by using image processing. The maximum variation of the resonance frequency is measured as 16.5% of the nominal frequency when using an excitation current of 300 mA. Thus, it is expected that the Lorentz force excitation can be applied to both drive and tune the behavior of the proposed PB-EMS.

A bound on the capacity of the causal dirty paper problem with arbitrary interference and general independent identically distributed additive noise is derived. In particular, it is shown that for the case of Gaussian noise the capacity is upper bounded by log 2 (1 + SNR over e) bits per real dimension. This bound is useful for SNR ≤ e(e - 2).

Joint pushing and proactive caching holds the promise of significantly increasing the throughput and decreasing the latency of content-centric wireless networks. In this work, we import the pushing and caching mechanism into a traditional packet-oriented network for decreasing the average queueing delay. Since the decreasing relies on extra costs paid for the pushing-caching mechanism, such as the cost for the cache buffer's capacity, extra transmission power for pushing and so on, we mainly derive the average queueing delay under given cost in order to study the relationship between the average queueing delay and the extra cost. In order to do so, a metric named System State is defined to describe the transmitter and user's current buffer states. Based on the System State, a two-dimensional Markov Chain is built to derive the average queueing delay and the average hitting ratio. The results show us how much the average queueing delay can achieve when the cache buffer's capacity which usually has a high cost is given, and then provide us a method to make a tradeoff between the average queueing delay and the cost of the user's buffer size. Simulation results validate our conclusion.

We study a dirty paper channel model where the input is constrained to belong to a PAM constellation. In particular, we provide lower bounds on the capacity as well as explicit coding schemes for the binary-input dirty- paper channel. We examine the case of causal as well as non-causal side information.

We design a coding scheme for Costa's dirty paper coding (DPC) (M.H.M. Costa, 1983) using a channel and a shaping code. We show that by transforming the channel noise distribution the DPC channel can be converted into the binary erasure channel (BEC) with binary interference with memory. Furthermore, the messages exchanged during the iterative decoding between the channel and shaping codes become one dimensional under the new model. We analyze the iterative decoding and find good shaping and channel code pairs using some closed-form extrinsic information transfer (EXIT) curves. We verify that our dirty paper codes designed using this method are also good for the original DPC channel with the additive white Gaussian noise (AWGN) and arbitrary interference. Our implementation of DPC uses short block codes such as repetition codes for shaping codes. Although the shaping gains of such codes are not very high, they may provide a better complexity-performance trade-off for simple practical implementations of DPC. Furthermore, we show accurate theoretical analysis is possible for such codes under our channel model.

Costa's "writing on dirty paper" capacity result establishes that full state pre-cancellation can be attained in the Gel'fand-Pinsker channel with additive state and additive Gaussian noise. The "carbon copy onto dirty paper" channel is the extension of Costa's model to the compound setting: here a common message is to be decoded at M receivers, each observing the sum of the channel input, Gaussian noise and one of M possible state sequences. As in the Gel'fand-Pinsker channel, the state sequences are anti-causally known at the encoder, which can thus pre-code its transmissions so as to minimize the adverse effects of the channel states. In this paper we derive the capacity to within 2.25 bits-per-channel-use of the M-user "carbon copying onto dirty paper" channel in which the state sequences are Gaussian distributed with the same variance and the same pairwise correlation.