Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-11-23T21:08:30Z No. of bitstreams: 1 Dissertação - Cláudio Henrique Albuquerque Rodrigues.pdf: 3025271 bytes, checksum: 33bddf32584a136783577f65549474ff (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-11-27T20:36:37Z (GMT) No. of bitstreams: 1 Dissertação - Cláudio Henrique Albuquerque Rodrigues.pdf: 3025271 bytes, checksum: 33bddf32584a136783577f65549474ff (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-11-27T20:43:17Z (GMT) No. of bitstreams: 1 Dissertação - Cláudio Henrique Albuquerque Rodrigues.pdf: 3025271 bytes, checksum: 33bddf32584a136783577f65549474ff (MD5) / Made available in DSpace on 2015-11-27T20:43:17Z (GMT). No. of bitstreams: 1 Dissertação - Cláudio Henrique Albuquerque Rodrigues.pdf: 3025271 bytes, checksum: 33bddf32584a136783577f65549474ff (MD5) Previous issue date: 2015-09-11 / Não informada / The Second Screen is a technology created to offer the viewer the ability to interact with the content through mobile devices using applications created for this purpose. It is a platform that is already being used in cable television and satellite television, on some channels available in this type of business, pay TV. It is also used in available content through Bluray media and movie theaters. Among the new applications and services of the companies in the field of electronic games, there are applications that allow players to transform smartphones and tablets on a second screen to enhance the overall experience of a player compared to controls and challenges of a game. The purpose of this work is to create an interactive application prototype for Brazilian System of Digital Television - SBTVD in the ISDB-TB standard (Integrated Services Digital Broadcasting Terrestrial Brazil), that provides the second screen technology in mobile viewers. For this, it will be carried out changes in the signal generated by content providers to inclusion of the second screen option and creating the necessary conditions for detection, synchronization and use of this technology by the end user at his residence. To check the operation of the proposal, it was set up a test environment with the necessary components to simulate the complete system. / A segunda tela, ou em inglês, second screen é uma tecnologia criada para oferecer ao telespectador a possibilidade de interagir com o conteúdo por meio de dispositivos móveis, utilizando aplicativos criados para este fim. Trata-se de uma plataforma que já está sendo utilizada na TV a cabo e na TV via satélite, em alguns canais disponibilizados nesta modalidade de negócio, TV por assinatura. É utilizada também em conteúdos disponibilizados através de mídia BluRay e nas salas de cinema. Entre as novas aplicações e serviços das empresas do ramo de jogos eletrônicos, já existem aplicações que permitem aos jogadores transformarem smartphones e tablets em uma segunda tela para melhorar a experiência geral de um jogador em relação aos controles e desafios de um jogo. A proposta deste trabalho é criar um protótipo de aplicação interativa para o Sistema Brasileiro de Televisão Digital - SBTVD no padrão ISDB-TB (Integrated Services Digital Broadcasting Terrestrial Brazil), que permita disponibilizar a tecnologia de segunda tela em dispositivos móveis aos telespectadores. Para isto, serão realizadas alterações no sinal gerado pelos provedores de conteúdo para inclusão da opção de segunda tela e a criação das condições necessárias para detecção, sincronização e utilização desta tecnologia pelo usuário final em sua residência. Para verificar o funcionamento da proposta, foi criado um ambiente de testes com os componentes necessários para simular o sistema completo.

Este trabalho apresenta um método que simula o desempenho dos sistemas de registro radiológicos, considerando tanto a capacidade de absorção, a eficiência de conversão, o espectro de emissão e a eficiência intrínseca do écran quanto a distribuição espacial dos fótons de luz, o ruído quântico, o espectro de sensibilidade do filme, a quantidade de fótons necessários para tomar o grão haleto de prata revelável e um fator que engloba os parâmetros que não são diretamente fornecidos pelos fabricantes. Implementamos os algoritmos empregando o ambiente de programação Delphi, uma ferramenta de desenvolvimento de aplicações para plataforma Windows e microcomputador, que possibilitou o desenvolvimento de uma interface amigável de interação com o usuário. O método prevê a influência de qualquer combinação écran-filme usada ou planejada sobre a nitidez de imagens radiográficas e permite simular o contraste e a nitidez da imagem a ser obtida para uma dada combinação écran-filme em função da exposição quanto a sua curva H&D. / This work presents a method that simulates the performance of radiological recording systems, considering the absorption capacity, the conversion efficiency, the emission spectrum and the intrinsic efficiency of the intensifying screen, the spatial distribution of the light photon, the quantum noise, the sensibility spectrum of the radiographic film, the necessary photons to become the silver halide grain developable and a factor that includes the parameters that are not supplied directly by the manufacturer. We have implemented the algorithms using the Delphi programming language, an application development tool for Windows and personal computer, which allowed the development of a friendly interface of interaction with the user. The method predicts the influence of any screen-film system used or planned on radiographic image sharpness and allows one to simulate the contrast and the image sharpness to be obtained with a given screen-film combination in function of the x-ray exposure as well as the H&D curve this combination.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-06-15T12:48:16Z No. of bitstreams: 1 mayradeoliveirasa.pdf: 2417121 bytes, checksum: f0d0f8875d10d1bd97ea4054d5b1a86b (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T14:10:48Z (GMT) No. of bitstreams: 1 mayradeoliveirasa.pdf: 2417121 bytes, checksum: f0d0f8875d10d1bd97ea4054d5b1a86b (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T14:11:08Z (GMT) No. of bitstreams: 1 mayradeoliveirasa.pdf: 2417121 bytes, checksum: f0d0f8875d10d1bd97ea4054d5b1a86b (MD5) / Made available in DSpace on 2016-07-13T14:11:08Z (GMT). No. of bitstreams: 1 mayradeoliveirasa.pdf: 2417121 bytes, checksum: f0d0f8875d10d1bd97ea4054d5b1a86b (MD5) Previous issue date: 2016-02-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente trabalho é um estudo sobre a TV digital brasileira, principalmente em relação as suas propostas de inclusão digital, através da interatividade com o público. Para isso, a partir dos estudos de Mattos (2002), Jambeiro (2008), Machado (2003) e Barbosa (2007), são apresentados tanto a evolução da TV, quanto as características que fazem da televisão, ainda hoje, o principal veículo de comunicação no Brasil. Após isso, a pesquisa volta-se para as propostas de interatividade da TV aberta, por meio dos aplicativos para outros dispositivos, com destaque para autores como Primo (2003) e Santaella (2010). Com a análise do funcionamento e dos conteúdos do aplicativo para as partidas de futebol exibidas pela TV Globo, a partir da Copa do Mundo de 2014, e também com a da apresentação de dois projetos desenvolvidos pelo grupo de pesquisa Laboratório de Mídia Digital da UFJF, o trabalho busca comparar o que se tem visto como estratégia das grandes produtoras de conteúdo televisivo e em trabalhos que se dedicam a essa temática, feitos em âmbito experimental e acadêmico. / The present work is a study on the Brazilian digital TV, especially regarding its proposals for digital inclusion, through the interactivity with the audience. To do this, from the studies of Mandy (2002), Jambeiro (2008), Machado (2003) and Barbosa (2007), are presented both the evolution of TV as the features that make television, the main vehicle of communication in Brazil still today. After that, the search turns to open TV interactivity proposals through the apps for other devices, especially for authors such as Primo (2003) and Santaella (2010). With the analysis of the functioning and contents of the application to the football matches shown on TV Globo, from the 2014 FIFA World Cup, and also with the presentation of two projects developed by the research group Digital Media Lab of Juiz de Fora Federal University, the work seeks to compare what's seen as a strategy of the major producers of TV content and in jobs that are dedicated to this subject, made in experimental and academic level.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-12T14:34:55Z No. of bitstreams: 1 brunovieiramoreira.pdf: 2986462 bytes, checksum: c198dea2a937b12bd2ca08fbd5e3e153 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T16:48:50Z (GMT) No. of bitstreams: 1 brunovieiramoreira.pdf: 2986462 bytes, checksum: c198dea2a937b12bd2ca08fbd5e3e153 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-13T16:49:08Z (GMT) No. of bitstreams: 1 brunovieiramoreira.pdf: 2986462 bytes, checksum: c198dea2a937b12bd2ca08fbd5e3e153 (MD5) / Made available in DSpace on 2016-07-13T16:49:08Z (GMT). No. of bitstreams: 1 brunovieiramoreira.pdf: 2986462 bytes, checksum: c198dea2a937b12bd2ca08fbd5e3e153 (MD5) Previous issue date: 2012-03-21 / A Revolução Industrial acabou por constituir uma sociedade de consumo. Essa sociedade utiliza-se da publicidade e da propaganda, dentro do campo da comunicação, como forma de promover o consumo através do contato direto e da orientação do consumidor. A partir do surgimento das tecnologias digitais de comunicação, novas formas de atingir o sujeito contemporâneo vêm surgindo, fazendo com que o campo da comunicação se reoriente. O propósito do presente estudo é apresentar e refletir criticamente sobre o digital signage e suas representações na sociedade do consumo e se essa nova ferramenta de comunicação é eficaz e pode ajudar a manter o propósito da publicidade e propaganda. / The Industrial Revolution turned out to constitute a consumer society. This society uses the publicity and advertising, in the field of communication, as a way to promote consumption through direct contact and customer orientation. From the rise of digital communications technologies, new ways to reach the contemporary subject have emerged, making the field of communication reoriented. The purpose of this study is to present and reflect critically about the digital signage and its representations in the society of consumption and if this new communication tool is effective and can help keep the purpose of publicity and advertising.

Many everyday systems and products seem to be designed with little regard to usability. This leads to the frustration, wasted time and errors. So the usability of the product is important for its survival in the market. In many previous studies the usability evaluation of the iPhone and iPad carried out individually and very little work has been done on the comparative usability evaluation. However, there was not any study conducted on the comparative usability evaluation and measuring the performance of the iPhone versus iPad in a controlled environment. In this research work, the authors performed the comparative usability evaluation and measured the performances of the iPhone and iPad on the selected applications by considering the young users as well as the elderly users. Another objective of this study is to identify the usability issues in performances of the iPhone and iPad. A survey and experiment techniques were used to achieve the dened objectives. The survey questionnaire consisted of 42 statements that presented the different usability aspects. The objectives of the survey study were to validate the identified issues from the literature study, identify new issues and measure the signicant difference in user opinions for the iPhone and iPad. However, the experiment studies helped to measure the performance significances between the devices against the three user groups (novice user, experienced user, elderly user) and among the groups over the devices. Further, objective was to measure the satisfaction level of the participated users against the iPhone and iPad. The experiment was performed in a controlled environment. Total six tasks (two tasks per application) were dened and each participant performed the same task on both devices. Generally the authors found that the participants performed better on the iPad with lower error rates as compare to the iPhone. / The aim of this study was to evaluate and measure the comparative usability performances of the iPhone an iPad. The preliminary focus of the study was to nd the usability issues regarding both the devices. Several dierent methods have been used in the study when investigating the answers of predened research questions. The study in this thesis was a literature review, a survey study and an empirical usability testing experiment. In the literature review, the authors studied the dierent usability issues such as inconsistency in applications, applications crashes and accidental errors.The detail list of the issues also presented in Table 2. However, the survey responses validated such issues and highlighted some additional issues such as low battery time, Blue-tooth connectivity problems, wireless connectivity problem, week signal strength and missing help. Two participants commented on the missing of a swyping feature. According to them if the iPhone and iPad had such feature then their typing performance should be improved. A survey study was conducted to evaluate and measure the significance in the four main parts of the devices i.e. system, touch screen, keypad and applications. Each part contained the multiple related statements that explored the different usability aspects. The detail and results of each statement are given in Table 4. After the statistical analysis, the authors did not nd a signicant dierence between the statements regarding the iPhone and iPad apart from in four statements. In the two statements (i.e. nding a new application in the Apple store and replacing the contents location on the interface) the users agreed that the iPad performance was better than the iPhone. However, in the other two statements (i.e. use of system in the sun light and zooming gestures) they preferred the iPhone rather than the iPad. Its means 90.47% users addressed the same issues in the iPhone and iPad. There is no dierence in their preferences regarding the iPhone and iPad. 4.76% users preferred the iPhone and 4.46% users preferred the iPad in above mentioned conditions. The empirical usability testing experiment focused on studying the usability performances of the iPhone and iPad considering three target groups. The performances comparisons were conducted by comparing the dierent participants groups and both devices. In total 60 users participated in the empirical usability performance testing study. The selection of the participants was based on their earlier experience with mobile phones usage. The detail of the participant are given in Figure 13. The comparisons results of the participant groups are shown in Table 7, the devices in Table 8 and the errors on both devices in Table 9 provided the signicance in the performances. The novice users versus experienced users comparison results across the iPhone (all six tasks) and the iPad (rst ve tasks) presented that the experienced users performed faster than the novice users with lower error rate. The results of the novice users versus elderly user comparison presented that the novice user using the iPhone ( first four tasks) and using the iPad (facebook login, location close view, new note and Evernote logout) performed faster than the elderly users with lower error rate. Similarly the results in the last comparison of the experienced users versus elderly users shown that the experienced users performed all the six tasks faster than the elderly users with lower error rate. Based on such nding the authors can conclude that the experienced users performances were better than the other two groups on both devices. The authors can also conclude that if someone is using the iPhone he/she could easily use the iPad. In the devices comparison results, the performances of the iPad across the novice users (in tasks facebook login, send a message, location close view, new note Evernote logout), the experienced users (in tasks facebook login, send a message, location close view and new note) and the elderly users (st ve tasks) were better than the iPhone with lower error rate. Base on such ndings of the empirical usability testing, the authors conclude that in the controlled environment the performance of the iPad was better than the iPhone. Three participant groups performed each task faster on the iPad than the iPhone apart from in one task. The task named location identication the iPhone and iPad performed the same across the novice user and experienced user but across the elderly user, the iPad performed better than the iPhone. Table 10 presents the results of the satisfaction level of the participants in a control environment for both devices. The satisfaction level acquired through the post test questionnaire during the experiment. The results of the novice users and the experienced users presented that their satisfaction levels were higher for the iPad than the iPhone. The experienced users results shown that their satisfaction levels were same for the iPhone as well as for the iPad. However, with the keypads performances they looked more satisfied on the iPad than the iPhone. / Near Chungi number 1 Chitterpari Mirpur Azad Kashmir Pakistan.

Ambient Occlusion är en teknik för ambient ljussättning i digitala tredimensionella scener. Sådana scener ljussätts vanligtvis med en konstant mängd ambient ljus på samtliga ytor oberoende av ytornas vinkel och position gentemot olika ljuskällor i scenen. Detta ger ett platt och kalt intryck och utan vidare ljussättningstekniker är det ytterst svårt att urskönja detaljer i scenen. Ambient Occlusion åthjälper detta genom att reducera mängden ambient ljus i vissa delar av scenen. Ambient ljus är en enkel approximation av det reflekterade diffusa ljuset som antas nå nästan överallt i scenen. Genom att sänka det ambienta ljuset på punkter i scenen med tät eller täckande geometri så ger Ambient Occlusion ett intryck av att det sekundära diffusa ljuset ej når dessa platser. Pappret undersöker en äldre variant av Ambient Occlusion där mängden ambient ljus beräknas statiskt för en scen och sparas i texturer. Vidare undersöks nyare metoder där mängden ambient ljus beräknas dynamiskt på den renderade scenen i Pixel Shaders. Det senare tillvägagångssättet kallas Image Based Ambient Occlusion eller Screen Space Ambient Occlusion. Detta nya tillvägagångssätt jämförs mot den traditionella angreppsvinkeln med förberäknade texturer. Teknikerna utvärderas och jämförs mot varandra i avseende på tids- och minneskomplexitet, enkelhet och visuellt resultat utöver specifika egenskaper för de enskilda teknikerna. Arbetets resultat beskrivs i slutet av rapporten. I resultatet presenteras hur shaderteknikerna pga sina brister inte är applicerbara i alla scener.

Dans le passé, Nichols et al. (Cell, 2010) ont criblé une collection de mutants de déletion d’Escherichia coli (~4000 gènes) dans ~324 conditions. L’utilisation de la taille des colonies comme indicateur de croissance, leur a permis de définir des phénotypes robustes pour ~50% des mutants, conduisant ainsi à de nouvelles idées biologiques. Cependant, 50% des gènes restants n’ont pas donné de réponse significative.J’ai souhaité dépasser les limitations du précédent criblage en augmentant le crible dans 2 directions : tout d’abord, j’ai augmenté le nombre et la complexité des conditions de stress dans le but d’imiter les contraintes d'origine naturelle. Puis, j’ai adapté le test «rouge Congo» afin de tester la formation de biofilm.J’ai ainsi généré deux ensembles de données, contenant ~2 millions de phénotypes de croissance et de biofilm, dans approximativement 250 conditions de stress simples et complexes. Les données ont révélé des phénotypes pour ~80% des mutants testés, la majorité d'entre eux provenant de conditions de stress complexes et de la mesure de biofilm. L'utilisation de ces phénotypes a permis la construction d’un réseau connectant les complexes de protéines connus avec ~500 gènes de fonction inconnue.De plus, la mesure de biofilm a permis d’identifier de nouveaux acteurs impliqués dans la formation de biofilm. Les données obtenues grâce au test «rouge Congo» ont également révélé que de nombreux enzymes régulant les niveaux de ci-di-GMP servent de senseurs pour différents signaux entrants impliqués dans cette même voie. L’identité des signaux entrants a été révélée par les phénotypes spécifiques à une condition. / In the past, Nichols et al. probed a knock out collection of E. coli across 324 conditions. Using colony size as a proxy for fitness allowed them to define robust phenotypes (5% FDR) for about 50% of the knockouts, leading to novel insights into E. coli’s biology. The remaining 50% of the genes did not yield a significant response even when growth was probed in such diverse conditions.I address the limitations of this previous high-throughput screen by expanding the screen design it in 2 directions: First, I increased the number and complexity of conditions to mimic naturally occurring stresses. Second, I adapted the Congo-red assay to probe biofilm formation in parallel to growth. I was able to generate two datasets that consist of more than 2 million growth and biofilm phenotypes across ~250 simple and complex stresses. The datasets revealed phenotypes for ~80% of the knockouts probed (5% FDR) with the large majority of them originating from complex stresses and the biofilm readout. Using these phenotypes, I generated a high-confident network connecting known protein complexes with >500 uncharacterized genes. In addition, the biofilm readout captured dozens of new players involved in biofilm formation. Even further, the color dataset revealed that the multiple enzymes regulating the levels of ci-di-GMP, serve as sensors for different input signals that feed into the same pathway. Identity of the input signals was revealed by the condition-specific phenotypes.

I denna uppsats undersöker vi hur tre olika tidpunkter för visning av information på en secondscreen uppfattas av personer. Målet med undersökningen är att få en inblick i hur tittare upplever information som visas på en second-screen. Vi hoppas att resultatet ska kunna bidra till utformingen av kommande second-screenapplikationer. Dessutom har vi undersökt om tidpunkten av när information visas påverkar minnet av det personer ser på second-screenen. Vi utförde tester på totalt 18 personer med hjälp av tre stycken prototyper och varje testperson blev intervjuad efteråt. / In this paper, we examine how three different times for displaying information on a second-screen is perceived by people. The goal of the survey is to get an insight in how viewers perceive information displayed on a second-screen. We hope that the results will contribute to the design of future second-screen applications. In addition, we investigated whether the timing of when the information is displayed, affects the memory of the people using the second-screen. We performed tests on a total of 18 people with the help of three prototypes, each subject was interviewed afterwards.

Denna rapport har undersökt hur interaktivitet, genom interaktiva barnböcker på mobila enheter med pekskärm, kan påverka engagemanget för läsande hos barn i tre till fem års ålder. Detta har gjorts genom att en interaktiv barnbok skapades och deltagande observationer sedan utfördes vid sex tillfällen på tre förskolor där barnen fick testa den utvecklade produkten. De deltagande observationerna kompletterades sedan med åsikter om digitalt lärande från förskollärare på respektive förskola genom semistrukturerade intervjuer. Resultatet från undersökningen visar på en tendens till att engagemanget hos barnen kan ökas genom att införa interaktivitet i barnböcker genom att leverera dessa på mobila enheter med pekskärm. Undersökningen är dock gjord i för liten skala samt att produkten och undersökningen innehåller för många brister för att kunna ställa upp en faktisk teori. Istället ställs en hypotes upp som skulle behöva testas vidare under längre tid och i en mer rigorös undersökning. / This paper has researched how interactivity, through interactive children’s books on mobile devices with touch screen, can affect the involvement in reading for children in the ages three to five years old. This has been done by creating an interactive children’s book and then conducting participative observations over six occasions at three different preschools where the children got to test the developed product. The observations were then supplemented with opinions on digital learning from preschool teachers from each of the schools through the use of semi-structured interviews. The result from this research shows a tendency that the involvement of the kids can be increased by introducing interactivity to children’s books by the use of mobile devices with touch screen. However the research is at too small a scale and both the product and the research contain too many flaws for an actual theory to be constructed. Instead a hypothesis is constructed that would need to be evaluated during a longer period of time and through more rigorous research.

Pas de résumé / Propagation of nonlinear acoustic waves in inhomogeneous media is an important problem inmany research domains of modern theoretical and applied acoustics. For example, studies onpropagation of high amplitude N-waves in turbulent atmosphere are relevant to the sonic boomproblem which involves high interest due to development of new civil supersonic aircrafts. Inrelation to sonic boom problem, many studies on spark-generated N-wave propagation through aturbulent layer were carried out in model laboratory-scale experiments which are more controlledand reproducible than field measurements. Propagation of high intensity focused ultrasound intissue (HIFU) is intensively studied for medical applications. HIFU is a basis of new surgicaldevices for noninvasive thermal and mechanical ablation of tumors.In this thesis, the problem of characterization of high amplitude N-waves generated in air byan electric spark was studied using combined acoustical and optical methods. The fine structureof shocks was deduced from the shadowgraphy images with a resolution that cannot be obtainedusing condenser microphones. It was shown that the combination of optical and acoustical methodsallows complete characterization of the N-waves.N-wave propagation through a layer of thermal turbulence was further studied in a laboratoryexperiment. The evolution of statistical distributions and average values of the most importantN-wave parameters was investigated at different propagation distances. Experimental results werecompared to data obtained in another experiment known in literature, where N-wave was propagatedthrough kinematic turbulence. It was shown that in the case of almost the same widths ofthe turbulent layers, values of the characteristic scales and rms of refractive index fluctuations, thekinematic turbulence leads to stronger distortions of the peak pressure and the shock rise time ofthe N-wave and to 2-3 greater probabilities to observe intense focusing in caustics.Effects of nonlinear propagation and random focusing on the statistics of N-wave amplitudewere studied theoretically using the KZK equation and the phase screen model. The phase screenwas characterized by the correlation length and the refraction length – the distance where firstcaustics occur. Probability distributions, mean values and standard deviations of the N-wave peakpressure were obtained from the numerical solutions and were presented as functions of the propagationdistance and the nonlinear length. Statistical results from the KZK model were comparedwith analytical predictions of the nonlinear geometrical acoustics approach (NGA). It was shown,that NGA approach is valid only up to the distance of one third of refraction length of the screen.Strong nonlinear effects were shown to suppress amplitude fluctuations. The effect of the scale ofinhomogeneities on amplitude statistics was also investigated.The problem of focusing of ultrasound beam through inhomogeneous medium is importantfor medical diagnostics and nondestructive testing problems. The inhomogeneities of biologicaltissue or of industrial materials can destroy beam focusing. In the thesis, distortions of a weaklynonlinear diagnostic beam focused through a phase layer of special configuration were consideredexperimentally and theoretically. Feasibility of selective destruction of focusing of differentharmonics in the beam was predicted in the modeling and confirmed in experiment.The most modern HIFU devices rely on using two-dimensional multi-element phased arrayswith elements randomly distributed over a segment of a spherical surface. Numerical experimentis an important tool to characterize pressure fields created by HIFU radiators. Intensity levels atthe focus of HIFU radiators can reach several tens of thousands of W/cm2, causing nonlinearpropagation effects and formation of shocks [...]