We find conditions under which direct and inverse limits of arbitrary indexed systems of topological Abelian groups are related via the duality defined by the continuous convergence structure. This generalizes known results by Kaplan about duality of direct and inverse sequences of locally compact Abelian groups.

Quality Management is an essential part of successful organisations. But the effect of it is mostly not directly visible. The effects are more indirect, and have a time lag till results appear. In today’s challenging times, all activities of an organisation have to proof their ability to add value. While Value Based Management is more focussed on financial value, other concepts and models like ...

Orthogonal Frequency Division Multiplexing (OFDM) is being used by the modern communication systems due to the increase in demand for high throughput wireless communication systems. OFDM has highly efficient spectrum usage and robustness to multipath fading channel impairments. The focus of the paper is to improve Discrete Fourier Transform (DFT)based channel estimator designed over a slow fadi...

A generalized modified ratio estimator is proposed for estimating the population mean using the known population parameters. It is shown that the simple random sampling without replacement sample mean, the usual ratio estimator, the linear regression estimator and all the existing modified ratio estimators are the particular cases of the proposed estimator. The bias and the mean squared error o...

Frequency Estimation of a complex exponential is a problem relevant to a large number of fields. In this paper a computationally efficient and accurate frequency estimator is presented using the guaranteed stable Sliding DFT which gives stability as well as computational efficiency. The estimator approaches Jacobsens estimator and Candans estimator for large N with an extra correction term mult...

In this paper, we construct a point estimator when assuming unequal and unknown variances by using the empirical Bayes approach in the classical normal mean problem. The proposed estimator shrinks both means and variances, and is thus called the double shrinkage estimator. Extensive numerical studies indicate that the double shrinkage estimator has lower Bayes risk than the estimator which shri...

Extended Abstract. It is a traditional way in biological, sociological, agricultural and geological studies to partition a geographical area into quadrats and then take a sample of them by a particular sampling design. We study the relevant characteristic of quadrats to estimate a parameter of the population. We suppose that the variable of interest has a positive spatial autocorrelation. Sampl...

A new frequency estimator for a single complex sinusoid in complex white Gaussian noise is proposed. The estimator is more computationally efficient than the optimal maximum likelihood estimator yet attains as good performance at moderately high signal-tonoise ratios. Also, the estimator is shown to be related to the linear prediction estimator. This relationship is exploited to reveal why the ...

We introduce an unbiased two-parameter estimator based on prior information and two-parameter estimator proposed by Özkale and Kaçıranlar, 2007. Then we discuss its properties and our results show that the new estimator is better than the two-parameter estimator, the ordinary least squares estimator, and explain the almost unbiased two-parameter estimator which is proposed by Wu and Yang, 2013....