TOBIAS WÜNSCHER (corresponding author), email: [email protected], tel. 3 +49 (0)228 73 1851, fax. +49 (0)228 73 1869 4 5 MERCELYNE KHALUMBA, email: [email protected] 6 7 KARIN HOLM-MÜLLER , email: [email protected] 8 9 MIRJAM BÜDENBENDER, email: [email protected] 10 11 Center for Development Research, University of Bonn, Walter-Flex-Str. 3, 53227 ...

3D beamforming is a technique which allows the adaptation of the base station (BS) antenna downtilt per user equipment (UE). The selection of the appropriate downtilt depends on the propagation properties of the environment. This paper investigates the optimum downtilt angle in a typical nonline-of-sight (NLOS) urban outdoor environment. Therefore measurements with variable downtilt have been c...

The proliferation of technology requiring user authentication has increased the number of passwords which users have to remember, creating a significant usability problem. This paper reports a usability comparison between a new mechanism for user authentication Passfaces and passwords, with 34 student participants in a 3-month field trial. Fewer login errors were made with Passfaces, even when ...

Intel PRO/10GbE LR adapter is the first commercially available 10 Gigabit Ethernet adapter for PC. In this report we describe our observations about the adapter functionality and performance, with respect to the possibility of the use for 10 Gigabit end-to-end communication over a wide-area network. 1 Obtaining adapters Intel PRO/10GbE LR is the first commercially available 10 Gigabit Ethernet ...

Today's available solutions for the production of digitally compressed TV programmes require successive decoding and re-coding operations due both to the multiplicity of digital formats currently in use for signal acquisition and to technology limitations. This has the consequence of increasing the production costs and of reducing the overall signal quality. The ability of using compression als...

We present measurement results with a GSM1800 smart antenna base station. The base station is equipped with an adaptive antenna array processor that allows in every GSM frame full beam adaptation in uplink and downlink. The smart antenna processing is based on the estimation of the directions of arrival in uplink. It includes separate DOA trackers for uplink and downlink, angular diversity, and...

The present study was carried out to evaluate the effectiveness of a specific program regarding the occurrence of vocal attrition symptoms in telemarketers. A total of 71 subjects participated in this study: 28 completed the Vocal Symptoms questionnaire to test its reliability, and 43 were randomly assigned to two groups: an 8-week vocal training group (n = 14) and a no-training control group (...

There is now an extensive literature on “gift exchange” showing that when principals and agents can trade “gifts” (rewards that should not emerge in a competitive equilibrium), exchange becomes more efficient. However, it is not obvious how gift exchange should be organized if the principal’s goal is to increase the performance of a reciprocal agent. Specifically, who should make the first gift...

Speech recognition techniques are most useful when used over the phone. A telephone speech recognizer was developed and many field trials were carried out[1][2][3]. We have developed telephone speech recognition hardware for a voice-activated home banking system based on a client-server network configuration[4]. The speech recognition unit is a workstation with six boards for dealing with simul...

Control of Chagas’ disease vectors in Central and South America has relied principally on repeated spraying of infested houses with benzene hexachloride (BHC) or dieldrin. Nevertheless, the continued use of these chlorinated hydrocarbon insecticides is currently under review. In Venezuela, strains of Rhodnius prolixus resistant to dieldrin and crossresistant to BHC have already emerged (1, Z), ...