• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2312
  • 603
  • 320
  • 318
  • 305
  • 144
  • 73
  • 42
  • 38
  • 37
  • 29
  • 19
  • 18
  • 15
  • 12
  • Tagged with
  • 5438
  • 661
  • 552
  • 537
  • 502
  • 461
  • 428
  • 409
  • 332
  • 312
  • 311
  • 301
  • 293
  • 274
  • 267
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
971

A systematic review on noise-induced hearing loss prevention and conservation programs in children and adolescents

He, Chenjin, 何晨瑾 January 2013 (has links)
Children suffering from noise-induced hearing loss could have disease burden such as communication difficulties, frustration, isolation as well as impaired self-cognition due to different degrees of hearing loss. Lack of hearing protection was the easiest way to tackle among the risk factors. Hence, the aim of this review is to review and synthesize existing evidence to show the effects of hearing conservation programs targeted on children and adolescents. Six studies included meeting strict requirements of inclusion and exclusion criteria. Significant improvements were shown in knowledge, attitude, intended behavior as well as hearing protective devices use regarding educational programs. However, limited effective consequence was shown in terms of audiometric threshold testing, thus, indicating limited effectiveness of educational programs in noise-induced hearing loss prevention. The results of hearing conservation programs were illustrated in details. And limitations as well as implications were discussed. / published_or_final_version / Medicine / Master / Master of Public Health
972

Environmental noise and non-auditory health impacts in Hong Kong

Ruan, Ruoling, 阮若琳 January 2014 (has links)
The magnitude of noise pollution is fast-growing worldwide. Environmental noise has been linked with several non-auditory health impacts, including annoyance, sleep disturbance, cardiovascular diseases and impaired cognitive performance. Also, environmental noise exposure is associated with increased reported psychological symptoms, prolonged healing time of patients and poorer performance of staff in hospitals. Hong Kong has been suffering from environmental noise for years, especially transportation noise, but lack of relevant local studies to support public health intervention. This review is attempted to summarize three governmental study reports and overseas studies on the relationship between noise and non-auditory effects. Also data on noise complaints will be briefly analysed as a supplement. It is ascertained that noise pollution and noise-induced annoyance and sleep disturbance are prevalent in Hong Kong. Also, noise mapping and subjective auditory effect scales are already available. Noise complaint level in Hong Kong is generally lower than levels in London and New York City, but is probably underestimated. Future studies are needed to emphasize on noise exposure in particular areas and vulnerable populations / published_or_final_version / Public Health / Master / Master of Public Health
973

Arts of Noise: Sound and Media in Milan ca. 1900

Williams, Gavin January 2013 (has links)
This dissertation explores the place of sound, noise and silence in Milan at the turn of the twentieth century. By focusing on this particular urban environment, it aims to investigate the notion of sonic modernity through a series of four case studies. It begins in 1881, the year of the city's National Industrial Exposition, with the premiere of the ballet Excelsior--a work that, like the Exposition itself, celebrated modern progress by staging technological inventions and was preoccupied with industrial production. Pursuing these echoes of labor, a second case study examines workers' songs, which comprised a resonant document in the rise of Italian socialism. These songs present us with a workers' culture that commemorated factory disputes and strikes; they also embody tensions in the interface between workers and socialists which, I argue, characterized the ways in which songs imagined urban space. In my third case study, my attention shifts to this urban imagination by focusing on a media event: the death of Giuseppe Verdi. Focusing on different contemporary interpretations of the respectful silence, as articulated through the city's transport and communication media, I argue that Verdi's death can provide a fresh perspective on the political unconscious of Milan's lugubrious fine secolo. It is against this historical context, that my fourth and final case study examines Luigi Russolo's famous "L'arte dei rumori" (The Art of Noises); in it, I seek to show that Russolo's ideas stand out against the resonant background of Milan's symbolic architectural sites and the noise of its human multitudes. Ultimately, this dissertation provides alternative contexts against which to understand Futurist noise, seeking to move beyond existing interpretations of Futurism as a turning point in music history and to position it instead as a refraction of Milan's increasingly industrial soundscape. / Music
974

A study of industrial hearing loss in Hong Kong: the contribution of impulsive noise characteristics

Hui, Yat-ming, Simon., 許一鳴. January 1983 (has links)
published_or_final_version / Industrial Engineering / Master / Master of Philosophy
975

Identifiering och utvärdering av växters bullerreducerande förmåga i urban miljö

Claesson, Elin January 2015 (has links)
Trafikbuller är den miljöstörning som påverkar flest människor i Sverige. Studier visar att buller kan påverka människors hälsa genom att orsaka hörselskador, stress, sömnsvårigheter och i förlängningen hjärt- och kärlsjukdomar. Idag byggs städerna i Sverige allt tätare, vilket gör att antalet bullerstörda personer fortsätter att öka. För att dämpa buller används ofta höga och breda bullerskärmar, vilket inte är att föredra i urban miljö. Ny forskning undersöker därför andra alternativ, bland annat hur växter och gröna områden kan verka bullerreducerande. Forskare menar att växter med hjälp av sina stammar, bladverk och substratet de står i kan reducera ljud genom reflektion, absorption och spridning av ljudenergin. Detta examensarbete syftade till att utvärdera olika växtelement ur bullerreducerande synpunkt. Växters bullerreducerande förmåga är något varken akustiker eller landskapsarkitekter generellt sett tar hänsyn till och därför ansågs en kunskapssammanställning ligga i tiden. För att göra detta har en litteraturstudie, två intervjuer samt mätningar på två växtelement utförts. Mätningarna gjordes på häckar längs Luthagsesplanaden i Uppsala och på en fasad med klätterväxter på Norr Mälarstrand i Stockholm. Litteratur- och intervjustudien visade att växtbeklädda bullerbarriärer hade högst potential att reducera buller längs vägar, gröna tak högst potential att reducera buller in på innergårdar och gröna fasader högst potential att dämpa buller på torg. Växter har också möjlighet att osynliggöra ljudkällor, vilket gör att vi upplever ljudet som lägre. Mätningarna visade att häcken på Luthagsesplanaden hade möjlighet att dämpa ljudet precis bakom häcken med upp till 3 decibel (dBA). Minskningen höll sig inte ända in till fasaden vilket tros bero på att det reflekterade ljudet dominerar i gaturummet samt att den avskärmande effekten minskar med ökat avstånd. Höga frekvenser dämpades bäst av häcken med den högsta dämpningen på 18 dBA för frekvensbandet 16000 Hz. Dämpningen av de höga frekvenserna syns även in vid fasaden med en dämpning kring 4-5 dBA. Häcken efterliknades i modelleringsprogrammet CadnaA med den nordiska beräkningsmodellen för vägtrafikbuller, men inget objekt tycktes kunna representera häcken på ett reproducerbart sätt. På Norr Mälarstrand visades ingen signifikant skillnad i varken ljudtrycksnivå eller frekvensfördelning från fasaden med klätterväxter. En dämpning på upp till 4 dBA för frekvenser över 800 Hz kan dock antydas in vid fasaden. Vid modellering av fasaden visades att varken en reflekterande eller en absorberande fasad kunde representera klätterväxterna. / Traffic noise is the environmental problem that affects most people in Sweden. Studies show that noise can affect human health by causing hearing damage, stress, insomnia and cardiovascular disease. Swedish cities today are built increasingly close, increasing the number of people that are affected by noise. Today, the most common way to reduce noise is to use barriers. In towns, this is not preferable and new research brings up other suggestions that can fit into an urban environment. Some studies are investigating how plants can reduce noise. Research has shown that plants by their trunks, foliage and substrate can reduce sound by reflection, absorption and diffusion. This thesis aimed to identify and evaluate various plant elements through a noise abatement perspective. This perspective is something neither acoustician nor landscape architects in general takes into account and was therefore considered useful. To do this, a literature study, two interviews and measurements were made. The measurements were made on hedges along Luthagsesplanaden in Uppsala and on a facade with climbing plants on Norr Mälarstrand in Stockholm. The literature and the interviews showed that vegetated noise barriers had the highest potential to reduce noise along roads, green roofs had the maximum potential to reduce noise in courtyards and green facades had the maximum potential to reduce noise in squares. Plants are also able to hide sound sources, enabling us to perceive the sound as lower. The measurements showed that the hedge were able to lower the sound pressure level up to 3 decibels (dBA). This reduction did not last to the facade, which is believed to be due to reflected sound dominating the street canyon and that the shielding ability decreases with increasing distance. The hedge was able to lower the higher frequencies the most with the maximum attenuation of 18 dBA for the frequency 16000 Hz. The attenuation of high frequencies is also visible close by the facade with attenuation around 4-5 dBA. The hedge were imitated by different elements in the sound modeling program CadnaA with the help of the Nordic calculation model for road traffic noise, but no element seemed to be able to represent the hedge. The measurement at Norr Mälarstrand showed no significant difference in either sound pressure level or frequency distribution by the facade with climbing plants. However, a damping of up to 4 dBA for frequencies above 800 Hz could be hinted from the measurement by the facade. When modeling the same it was shown that neither an absorbing facade nor a reflecting facade could represent the facade with climbing plants.
976

ESTIMATION OF NONSTATIONARY SIGNALS IN NOISE (PROCESSING, ADAPTIVE, WIENER FILTERS, ESTIMATION, DIGITAL)

Warner, Carl Michael, 1952- January 1986 (has links)
No description available.
977

Αφαίρεση θορύβου από ψηφιακές εικόνες μικροσυστοιχιών DNA

Θεοχαροπούλου, Ελένη 19 August 2009 (has links)
Στη διπλωματική αυτή γίνεται μελέτη κάποιων τεχνικών που χρησιμοποιούνται για την αφαίρεση θορύβου από εικόνες μικροσυστοιχιών DNA. Στη συνέχεια γίνεται εφαρμογή φίλτρου median και μετασχηματισμού κυματιδίων (wavelet) για την αφαίρεση θορύβου από πραγματικές εικόνες μικροσυστοιχιών και σύγκριση των αποτελεσμάτων. / -
978

Selection of pulse power in a CW environment

Butler, Walker, 1940- January 1969 (has links)
No description available.
979

Positive ion emission from palladium (effects of selected ambient gases)

Pope, Richard Alan, 1947- January 1971 (has links)
No description available.
980

Development of an analog computer noise generator

Manella, John Gust, 1937- January 1961 (has links)
No description available.

Page generated in 0.3295 seconds