Source arrays for directional and non-directional sound generation

In this paper, methods are presented to design an acoustic source array for both directional sound generation and non-directional sound generation. The methods are based on measured transfer functions to be able to take into account different source sensitivities, to use extended sources that cannot be regarded as point sources, and complex geometries modifying the radiation characteristics. The aim of this paper is to develop a sound source that can be integrated in passenger vehicles with the objective to warn vulnerable road users while minimising noise pollution. Nowadays, sensor systems exist which are able to reveal the position of the vulnerable road users, which can be used to optimise the performance of the warning signal generator. Based on this information, the signal generator is designed to generate the specified warning signal at the location of the vulnerable road user while minimising the noise pollution at other locations. Such a directional sound beam was realised with an array of controlled acoustic sources. Changes of the relative positions of the vehicle and the vulnerable road user require continuous adjustments of the sound beam. In an alternative operation mode the sound field should not be directional but uniform in a wide horizontal sector. It will be shown how to combine the different requirements of directional sound radiation and uniform sound radiation with a single array configuration. Practical sound sources mounted in cars should be as compact as possible. Therefore the efficiency of the array is an important property. It will be shown that different beam forming approaches can lead to significant differences in the efficiency of the array. The influence of beamforming parameters on the efficiency will be discussed as well as the physical interpretation of the resulting beamformer solutions. The acoustic results shown in this paper to illustrate these effects are obtained using numerical simulations based on FEM and BEM transfer function models of acoustic sources mounted in the front of a car, combined with models of the reflecting ground and other reflecting objects

Front Matter

nrpages: 11status: publishe

Simulation-based design of a steerable acoustic warning device to increase (H)EV detectability while reducing urban noise pollution

This paper describes the simulation-based design methodology used in the eVADER project for the development of targeted acoustic warning devices for increased detectability of Hybrid and Electric Vehicles (HEVs) while, at the same time, reducing urban noise pollution compared to conventional acoustic pedestrian warning systems. A key component of this system is an external warning signal generator capable of projecting the warning signals to a contained area in front of the vehicle where potential at-risk situations are detected. Using acoustic beam forming principles a suitable warning strategy and an initial layout for realizing such a system is defined. Starting from this information, acoustic Finite and Boundary Element models of the transducer array allow assessing more realistically the performance impact of the system integration and of the most critical changes in the acoustic environment in which the signal generator needs to operate

On the design of a (H)EV steerable warning device using acoustic beam forming and advanced numerical acoustic simulation

This paper describes the simulation-based design methodology used in the eVADER project for the development of targeted acoustic warning devices for increased detectability of Hybrid and Electric Vehicles (HEVs) while, at the same time, reducing urban noise pollution. A key component of this system is an external warning signal generator capable of projecting the warning signals to a contained area in front of the vehicle where potential at-risk situations are detected. Using acoustic beam forming principles a suitable warning strategy and an initial layout for realizing such a system is defined. Starting from this information, acoustic Finite and Boundary Element models of the transducer array allow assessing more realistically the performance impact of the system integration and of the most critical changes in the acoustic environment in which the signal generator needs to operate

Successful treatment of adenovirus infection with brincidofovir in an immunocompromised patient after hematological stem cell transplantation

Immunocompromised patients, including hematopoietic stem cell transplantation (HSCT), HIV, and malnourished patients, are at increased risk for viral infections with high incidences of morbidity and mortality. In HSCT patients, the infection risk is increased until immune reconstitution is re-established. Therapy with standard of care antiviral drugs, for example Cidofovir, is expensive, requires prolonged administration, and has unfavorable toxicity profiles. Our case describes the successful use of Brincidofovir (CMX001), a lipid-conjugate of the nucleotide analog Cidofovir, in a 9-year-old post-HSCT girl with disseminated adenovirus infection. The increased efficacy of Brincidofovir (BCV) against multiple viral infections, limited toxicity, and oral-administered schedule opens options in different resource settings

A psychobiographical study of Helen Keller

This psychobiographical study of Helen Keller’s life is exploratory-descriptive in nature. The subject was chosen through purposive sampling. The choice was based on the researcher’s personal interest and the remarkable impact this profoundly handicapped woman had within her society. Helen Keller also meets the psychobiographical requirements. These include that she is historically well known, inspirational, and her life has been completed. The study uses a qualitative, single case, interpretive research design. The design is employed to study Helen Keller’s entire life span within a formal psychological theory. The theory used in this study is Daniel Levinson’s (1996) Life Structure theory of adult development. Data for this study were collected from a variety of primary and secondary sources which provided alternative perspectives on her life. In addition, the data have been corroborated by historical texts, and newspaper and journal articles. Levinson’s (1996) theory divides the lifespan into four developmental eras, each with its own biopsychosocial character. Each era in turn is divided into shorter periods of development, each with particular developmental tasks. Cross-era transitions separate the eras. By describing and exploring the data according to this theory, Helen Keller as a profoundly handicapped person is shown to display universal patterns of development as suggested by Levinson. At the same time, the Life Structure she developed, her life components, and Satisfactoriness illuminated her uniqueness. Through the application of the theory to Helen Keller’s life, this psychobiographical study facilitated an examination of the theory. This led to suggestions for potential development of the theory

University Colleges can help smaller land surveying companies in introducing new data acquisition techniques

The ever developing instruments, techniques and software are at the same time a blessing and a curse for the contemporary land surveyor. Laser scanning is one of these new techniques and although its versatility, speed and accuracy are praised in articles and on exhibitions, a lot of Belgian land surveyors are somewhat reluctant to introduce laser scanning in their own company. There is still a lot of uncertainty in regard to the efficiency of this data acquisition method and especially the processing of the data and the production of deliverables that meet the client's needs and expectations. University Colleges can contribute to stimulate the smaller land surveying companies to invest in innovation and thus maintain their competitiveness and consolidate their position in an open European market. This article describes how researchers at university colleges translate their knowledge and experience in such a way that they can support smaller companies, which do not have the resources to do their own research, in making an educated decision concerning the introduction of laser scanning in their company

Unofficial Name-List of the Urban Residents of the Belorussian Lake District in the Areal Aspect

The article reveals areal features of the unofficial name-list of the urban residents of Belorussian Lake District in three ethnical and cultural parts: Belorussian-Lithuanian-Latvian border zone, central parts of Vitebsk region, and Byelorussian-Russian border zone. The study is based on the author’s classification of unofficial anthroponyms. The mapping method of describing intralinguistically motivated unofficial personal names has been used for the first time. Personal name-forms of different operating frequency are characterised in actual, inert zone and the zone of the unit coverage, which emphasises complex nominative priorities in the land area under study. Refs 14. Figs 3. Tables 2.Работа поддержана грантом БРФФИ № Г14М-103 договор от 23.05.2014 г. Тема: «Неофициальный ономастикон в социосфере Витебского региона». Номер госрегистрации: 20142540 от 10.10.2014