The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we mention our work on incorporating rule based reordering and morphological information for English to Malayalam statistical machine translation. The main ideas which have proven very effective are (i) reordering the English source sentence according to Malayalam syntax, and (ii) using the root suffix separation on both English and Malayalam words. The first one is done by applying...
We study randomized fingerprinting codes that achieve the fundamental capacity limits subject to the so-called Boneh-Shaw marking assumption. Two decoding schemes are studied in particular: the joint decoder is capacity-achieving but computationally intense, while the simple decoder is suboptimal but efficient. We provide tight bounds as well as numerical results for capacities and study the difference...
We consider the problem of data harvesting in wireless sensor networks. A designated collector node seeks to compute a function of the sensor measurements. For a directed graph G = (V ,??) on the sensor nodes, we wish to determine the optimal encoders on each edge which achieve zero-error block computation of the function at the collector node. Our goal is to characterize the rate region in R|??|...
Cooperative-diversity networks have recently been proposed as an effective technique to form virtual antenna arrays without using collocated multiple antennas. In this paper, we consider the adaptive decode-and-forward (DF) cooperative-diversity system with the Nth best-relay selection scheme. In the best-relay selection scheme, from the set of M relays the best relay only forwards the source signal...
In this paper, we analyze the performance of cooperative diversity wireless networks using amplify-and-forward (AF) or decode-and-forward (DF) relaying over independent, non-identically distributed Nakagami-m fading channels. We derive the symbol error probability (SEP) using the moment generating function (MGF) of the end-to-end signal-to-noise-ratio (SNR) at the destination. In AF relaying, and...
The ever-increasing demand for precious radio spectrum along with the inefficient usage of licensed band has led to the advent of the cognitive radio (CR) technology, which aims to provide opportunistic spectrum usage to unlicensed users and thus lead to the co-existence and interference control problem among heterogeneous systems. In this paper, an interference minimization and subcarrier power allocation...
We propose a new method for equivalence checking of RTL and schematic descriptions of memories using translation into first-order logic. Our method is based on a powerful abstraction of memories and address decoders within them. We propose two ways of axiomatizing some of the bit-vector operations, decoders, and memories. The first axiomatization uses an algebra of operations on bit-vectors. The second...
We introduce the use of fast flat histogram (FFH) method employing Wang Landau algorithm in an adaptive noise sampling framework using random walk to find out the pseudo-codewords and consequently the pseudo-weights for the belief propagation (BP) decoding of LDPC codes over an additive white Gaussian noise (AWGN) channel. The FFH method enables us to tease out pseudo-codewords at very high signal-to-noise...
Upper bounds on the mutual entropy of syndrome components of low-density parity-check (LDPC) codes are developed. Using these bounds, an upper bound is derived on the rates of LDPC codes for which reliable communication over a memoryless binary-input symmetric-output (MBIOS) channel is achievable. This bound improves on the earlier known bounds due to Gallager, Burshtein et al., and Weichmann-Sason.
We introduce a new family of graph-based source codes that can be regarded as a nonlinear generalization of LDPC codes, and apply them to the compression of asymmetric binary memoryless sources. Simulation results and the application of density evolution show that the proposed family presents a performance very close to the theoretical limits, clearly outperforming schemes based on linear codes.
The statistical mechanical interpretation of algorithmic information theory (AIT, for short) was introduced and developed by our former works [K. Tadaki, Local Proceedings of CiE 2008, pp. 425-434, 2008] and [K. Tadaki, Proceedings of LFCS'09, Springer's LNCS, vol. 5407, pp. 422-440, 2009], where we introduced the notion of thermodynamic quantities, such as partition function Z(T), free energy F (T),...
Distributed video coding (DVC) gains more and more interest in the recent decade. State-of-the-art Wyner-Ziv decoding is performed by a mandatory feedback channel. It's mandatory for rate allocation and high reconstruction quality. The feedback channel is a handicap for real application. If no feedback channel is available the RD-performance of the system is decreased. We propose a soft reconstruction...
We investigate the symbol error rate (SER) and outage probability of the cooperative transmission with the decode-and-forward relay protocol over dissimilar Rayleigh fading channels. The technique of orthogonal space-time block coding (STBC) is applied at the links of source-relay, source-destination and relay-destination. Closed-form expressions of outage probability and SER are derived, respectively...
We describe a scheme for rate-distortion with distributed encoding in which the sources to be compressed contain a common component. We show that this scheme is optimal in some situations and that it strictly improves upon existing schemes, which do not make full use of common components. This resolves in the negative an open question regarding whether independent quantization followed by independent...
This paper studied the identification algorithm of Chinese character coding type by analyzing the sub-sentence length. A sub-sentence definition is given in this paper and the pdf of sub-sentence length is analyzed based on the sentence samples from Lancaster corpus. We proposed a new algorithm to recognize the coding type of Chinese characters by splitting sentences into sub-sentences using Chinese...
Scheduling schemes always have impacts on system performances. This paper gives an analysis of Proportional Fairness (PF) and Maximum C/I (MCI) algorithms in downlink multiuser cooperative relay system with decode-and-forward (DF) protocol. Through an approximation of the signal-to-noise ratio (SNR), analytic expressions of system average throughput and fairness index under both scheduling schemes...
In this paper, transmission of fountain code over cooperative networks is considered. While it is known that fountain code is optimal for sending data to multiple receivers, extra care is needed when it is used in cooperative networks. On one hand, the presence of relay node can help to improve the overall performance. On the other hand, multiple relay nodes introduce the problem of mutual interference,...
A two-state compound relay channel is considered where the relay and the destination are informed about the channel state while the source is not. Achievable rates and upper bounds are derived for discrete memoryless and Gaussian models, and specialized to a scenario with orthogonal components. It is shown that, apart from some special cases, optimality conditions valid for decode-and-forward (DF)-based...
In this paper, we consider modulation codes for practical multilevel flash memory storage systems with q cell levels. Instead of maximizing the lifetime of the device we maximize the average amount of information stored per cell-level, which is defined as storage efficiency. Using this framework, we show that the worst-case criterion and the average-case criterion are two extreme cases of our objective...
In this paper we investigate the performance of linear interactive encoding and decoding based on syndrome accumulation(SA-IED) over binary LDPC ensembles. Assume that the source alphabet is GF(2), and the side information alphabet is finite. It is shown that we can construct universal SA-IED schemes, which are asymptotically optimal for any stationary ergodic source-side information pair. Our analysis...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.