In this paper we give approximation algorithms and inapproximability results for various asymmetric k-center with minimum coverage problems. In the k-center with minimum coverage problem, each center is required to serve a minimum number of clients. These problems have been studied by Lim et al. [Theor. Comput. Sci. 2005] in the symmetric setting. In the q-all-coverage k-center problem each cen...

When deploying a new mobile technology such as LTE, it is crucial to identify the factors that affect the radio network in terms of capacity and quality of service. In this context, network coverage is arguably the single most influential factor. This work presents a metaheuristic-optimization approach that automatically adapts the parameters of a signal-propagation model. The optimization proc...

The kinetics of tertiarybutylphosphine adsorption and phosphorus desorption from indium phosphide (001) have been determined using reflectance difference spectroscopy for real-time monitoring of the phosphorus coverage. The precursor adsorption rate depends linearly on the coverage, and the initial sticking coefficient varies from 0.007 to 0.001 as the temperature increases from 420 to 520 C. T...

To improve the unreasonable distribution of sensors' random deployment and increase network coverage rate, an optimization method of wireless sensor networks coverage based on improved shuffled frog leaping algorithm (ISFLA) was proposed in this paper.During the process of updating the frog, a novel learning strategy is introduced, in which the poor frog learns not only from the best frog of it...

introduction: immunization is one of the most important health programs in first level prevention and is also one of the most cost-effective prevention programs in the entire world. this study evaluates the situation of immunization in fewer than one year old afghan refugee children in kerman, iran. materials and methods: this was a cross-sectional study. data was extracted from the records of ...

The way address sequences and data patterns appear on the outside of a memory may differ from their internal appearance; this effect is referred to as scrambling, which has a large impact on the effectiveness of the used tests. This paper presents an analysis of address and data scrambling for memory chips, at the layout and at the electrical level. A method is presented to determine the data b...

A structurally testable delay fault might become untestable in the functional mode of the circuit due to logic or timing constraints or both. Experimental data suggests that there could be a large difference in the number of structurally and functionally testable delay faults. However, this difference is usually calculated based only on logic constraints. It is unclear how this difference would...

Students invariably ask the question \How large does n have to be for Z and t intervals to give appropriate coverage probabilities?" In this article we review the role of p 1 (X)= p n, where p 1 (X) is the skewness coeecient of the random sample, in the answer to this question. We also comment on the opposite eeect that p 1 (X) has on the behavior of t intervals compared to Z intervals. Finally...

investments in the extension of health insurance coverage, the strengthening of public health services, as well as primary care and better hospitals, highlights the emerging role of healthcare as part of china’s new growth regime, based on an expansion of services, and redistributive policies. such investments, apart from their central role in terms of relief for low-income people, serve to reb...

there are different methods for controling the flood damages which one of them is flood zoning. in this method, flood zones are determined by simulating river hydraulic behavior and its flood plain for different return periods.in other hand, soil and specially plant coverage are the most effective factor to determine manning roughness coefficient. so it is expected, seasonal plant coverage chan...