This paper gives a comparison of a low bandwidth, long range ultrasonic indoor communication system for room-level localization and a wide bandwidth coded system. The comparison is done using the link budget and focuses on range. Robustness, reliability and a range greater than 10 meters can be accomplished by coding 8 kHz bandwidth ultrasonic signals. Pseudo-random properties of the codes perm...

This paper assesses the prospects for the new Polish monetary policy strategy of inflation targeting. Regarding the general requirements for implementing an inflation targeting strategy it appears that Poland has made sufficient progress in reducing fiscal dominance and hardening budget constraints. The paper also finds that the exchange rate has played a dominant role as a policy instrument, w...

In this paper, we consider the effect of the initial sample size on the performance of a sequential approach that used in selecting a good enough simulated system, when the number of alternatives is very large. We implement a sequential approach on M/M/1 queuing system under some parameter settings, with a different choice of the initial sample sizes to explore the impacts on the performance of...

We consider how to allocate bandwidth in a multicast tree so as to optimize some global measure of performance. In our model each receiver has a budget to be used for bandwidth reservation on links along its path from the source, and each link has a cost function depending on the amount of total bandwidth reserved at the link by all receivers using that link. We formulate and solve a problem of...

We describe a method for generating sentences from “keywords” or “headwords”. This method consists of two main parts, candidate-text construction and evaluation. The construction part generates text sentences in the form of dependency trees by using complementary information to replace information that is missing because of a “knowledge gap” and other missing function words to generate natural ...

In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth’s atmosphere. Based on statistical rain rates data for Bulgaria, the link...

Calibration of Optical Time Domain Reflectometer (OTDR) has a crucial role for the accurate determination of fault locations and the accurate calculation of loss budget of long-haul optical fibre links during installation and repair. A comparison has been made between the Egyptian National Institute for Standards (NIS-Egypt) and the National Metrology institute of South Africa (NMISA-South Afri...

This work is focused on the atmospheric turbulence effect and a new method for determining optical signal attenuation caused by turbulence is presented here. A new method of power budget of optical links comes from optical intensity distribution in a laser beam after the beam passed through turbulent atmosphere. Results given by this method are compared with Rytov approximation which is nowaday...

In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth’s atmosphere. Based on statistical rain rates data for Bulgaria, the link...