Banu Gunel

Banu Gunel
Middle East Technical University | METU · Department of Information Systems

BSc, MSc, PhD

About

43
Publications
5,644
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
235
Citations
Additional affiliations
June 2004 - November 2010
University of Surrey
Position
  • PostDoc Position
September 2001 - June 2004
Queen's University Belfast
Position
  • PhD Student

Publications

Publications (43)
Article
Full-text available
Forming high quality requirements has a direct impact on project success. Gathering security requirements could be challenging, since it demands a multidisciplinary approach and security expertise. Security requirements repository enables an effective alternative for addressing this challenge. The main objective of this paper is to present the desi...
Article
Full-text available
As the number of web applications and the corresponding number and sophistication of the threats increases, creating new tools that are efficient and accessible becomes essential. Although there is much research concentrating on network security visualizations, there are only a few studies considering the web application vulnerabilities’ possible v...
Chapter
Security visualization has been an issue, and it continues to grow in many directions. In order to give sufficient security visualization designs, information both in many different aspects of visualization techniques and the security problems is required. More beneficial designs depend on decisions that include use cases covering security artifact...
Article
Types and complexity of information security related vulnerabilities are growing rapidly and present numerous challenges to the enterprises. One of the key challenges is to identify the optimal set of precautions with limited budget. Despite the fact that majority of enterprises have a budget constraint for installing and maintaining the protection...
Article
Video streaming, whether on demand or live, has become one of the most popular internet applications. However, financial investments required for it is a severe problem since it needs more real time storage, higher data transfer and a significant amount of computation than other kinds of multimedia data. To tackle this problem, cloud computing, off...
Conference Paper
Full-text available
This study aims to shed light on various aspects of refugees’ lives in Turkey using mobile call data records of Türk Telekom, which is enriched with numerous local data sets. To achieve this, we made use of several techniques in addition to a novel methodology we developed for this particular domain. Our results showed that refugees are highly mobi...
Conference Paper
In order to find gaps or missing points in any domain, examination of the literature work is necessary and provides a good amount of information. Doing a requirement analysis on top of this literature search incorporating the domain experts is a convenient way to find out ideas to fill out the detected gaps. The security visualization domain has be...
Conference Paper
Self-defense solutions on current aircraft usually handle advanced weapons while most helicopters down or damaged are known to be attacked from ground using rifles or Rocket-Propelled Grenades (RPG). Although there are ground based localization solutions for Small Arms Fire (SAF) attacks, there are only a few implementations of onboard applications...
Article
Full-text available
Hearing loss simulation (HLS) is a useful tool for hearing studies, since finding large numbers of hearing-impaired volunteers with various levels of hearing loss is usually a problem. Correct simulation of the hearing impaired ear should take into account different suprathreshold effects, such as reduced frequency selectivity, reduced audibility,...
Conference Paper
In computer graphics, proposing efficient and usable human-computer interaction design solutions is a challenging task. Well defined guidelines and principles are very useful for designers to design new solutions for systems. To create these guidelines and principles, firstly differences among systems should be identified. In this study, we focused...
Article
Full-text available
High frequency hearing loss is a growing problem for both children and adults. To overcome this impairment, different frequency lowering methods (FLMs) were tried from 1930s, however no satisfaction was provided up to now. In this study, for getting higher speech intelligibility, eight combinations of FLMs which were designed originally were tried...
Article
Full-text available
Objective: There are both objective and subjective tests for evaluating the speech intelligibility. Speech Intelligibility Index (SII) and Modified Rhyme Test (MRT) are the most common methods for objective and subjective tests, respectively. While objective tests do not depend on the language, subjective tests are applied to the hearing-impaired s...
Conference Paper
Full-text available
An audio recording, made in a real environment, carries an acoustical signature which changes according to the acoustical characteristics of the environment and the recording positions. This signature which is similar to a 3D room impulse response contains the directions, levels and arrival times of the direct source and reflections. Although it is...
Conference Paper
It is obvious that, human life is being affected by the facilities of new technologies with all of its aspects including learning and development. On the other hand, besides the increasing use of the facilities, we have limited knowledge about the question of how social interaction and Web 2.0 technologies affect the training environments in workpl...
Conference Paper
Full-text available
This paper presents an evaluation methodology to reveal the relationships between the attributes of software products, practices applied during the development phase and the user evaluation of the products. For the case study, the games sector has been chosen due to easy access to the user evaluation of this type of software products. Product attri...
Article
Pressure and pressure differences measured using closely-spaced microphone pairs enable the calculation of active intensity directions. These directions are exploited in various applications such as acoustical analysis and modelling, multichannel audio systems, source localization and real-time blind source separation. Despite their widespread usag...
Presentation
Patient interview is the process that provides the current complaints and medical history of the patient to the practitioner. Based on this interview, the practitioner tries to build a hypothesis about possible conditions depending on his/her knowledge and experience, This process can also start before the medical examination by obtaining prior kno...
Conference Paper
Full-text available
Within this paper a highly flexible approach for audio and visual attention modeling is presented. The developed system aims to be widely adaptable for different application scenarios within multimedia processing and coding. Possible use cases are presented and their influence on the system concept is shown. Furthermore the development of an attent...
Article
Spatial hearing enables translation of an auditory scene into a perceived 3-D image by interpreting the acoustic cues related to the sounding objects, their locations, and the physical characteristics of the space. Spatial audio production requires multichannel audio signals in order to convey this information and increase the realism of a real or...
Conference Paper
Full-text available
Free viewpoint video enables the visualisation of a scene from arbitrary viewpoints and directions. However, this flexibility in video rendering provides a challenge in 3D media for achieving spatial synchronicity between the audio and video objects. When the viewpoint is changed, its effect on the perceived audio scene should be considered to avoi...
Conference Paper
Full-text available
Delivery of 3D immersive entertainment to the home remains a highly challenging problem due to the large amount of data involved, and the need to support a wide variety of different displays. Support of such displays may require different numbers of views, delivered over time varying networks. This requires a delivery scheme featuring scalable comp...
Chapter
Automatic sound source localization has recently gained interest due to its various applications that range from surveillance to hearing aids, and teleconferencing to human computer interaction. Automatic sound source localization may refer to the process of determining only the direction of a sound source, which is known as the direction-of-arriva...
Conference Paper
In-situ audio recordings for forensic analysis are generally made using purpose-installed microphones in order to capture speech and other relevant sounds in an environment. Often, post-processing efforts are focused on cleaning these recordings from interference. An acoustic scene is made up of audio objects and their not only contents, but also p...
Article
Full-text available
Digital waveguide mesh (DWM) models are time-domain numerical methods providing computationally simple solutions for wave propagation problems. They have been used in various acoustical modeling and audio synthesis applications including synthesis of musical instrument sounds and speech, and modeling of room acoustics. A successful model of room ac...
Conference Paper
Full-text available
This article presents a technique that uses the intensity vector direction exploitation (IVDE) method for exhaustive separation of convolutive mixtures. While only a four-element compact sensor array is used, multiple channels for all possible source directions are produced by exhaustive separation. Singular value decomposition (SVD) is then applie...
Conference Paper
Full-text available
A multitude of convolutive blind source separation algorithms exist, a small number of which can deal with moving sources. The main assumption for moving source algorithms is that for a small amount of time the sources are approximately stationary and hence the mixing conditions are slowly varying. In reality, speech sources are likely to fall sile...
Article
Full-text available
Digital waveguide mesh (DWM) models offer a simple, accurate, time-domain, numerical solution of the wave equation. A specific case where such accurate and computationally simple solutions are needed is the acoustical modeling of open or closed volumes. It is possible to model 3-D propagation of waves in enclosures such as rooms using DWM models. G...
Article
Full-text available
Various techniques have previously been proposed for the separation of convolutive mixtures. These techniques can be classified as stochastic, adaptive, and deterministic. Stochastic methods are computationally expensive since they require an iterative process for the calculation of the demixing filters based on a separation criterion that usually...
Article
Full-text available
The evaluation of audio separation algorithms can either be performed objectively by calculation of numerical measures, or subjectively through listening tests. Although objective evaluation is inherently more straightforward, subjective listening tests are still essential in determining the perceived quality of separation. This paper aims to find...
Article
Full-text available
Microphone array signal processing techniques are extensively used for sound source localisation, acoustical characterisation and sound source separation, which are related to audio analysis. However, the use of microphone arrays for auralisation, which is generally related to synthesis, has been limited so far. This paper proposes a method for bin...
Article
Full-text available
Digital waveguide mesh (DWM) models are numerical solvers for the wave equation in -dimensions. They are used for obtaining the traveling-wave solution in practical acoustical modeling applications. Although unstructured meshes can be used with DWMs, regular mesh topologies are traditionally used due to their implementation simplicity. This letter...
Article
Full-text available
One of the simplest ways of designing allpass fractional-delay filters with maximally flat group delays is by using the Thiran approximation by which the filter coefficients are calculated using a closed-form equation. However, due to the number of multiplications and divisions involved, the calculation of these coefficients is a computationally co...
Article
This paper presents a passive analysis method for determining the spatio-temporal characteristics of sound fields in small rooms. The analysis finds an approximate directional reflectogram (ADR) which reveals the approximate arrival directions, time delays and amplitudes of the direct sound and early reflections without using a special or known sou...
Conference Paper
Plane wave decomposition (PWD) is an effective method for the analysis of sound fields. The use of spherical and circular microphone arrays with PWD has been well studied. In this paper, it is shown that PWD is also possible by using the recordings from a single rotating half-cardioid microphone. The microphone output is considered as the matrix pr...
Conference Paper
Digital waveguide meshes provide a computationally simple physical modelling approach for simulating wave propagation inside enclosures such as rooms. A digital waveguide mesh allows access both to the pressure values at scattering junctions and to the incoming and outgoing wave variables at those junctions. It is thus possible to access both the p...
Conference Paper
Full-text available
Fractional-delay filter is the general name given to filters modelling non-integer delays. Such filters have a flat phase delay for a wide frequency band, with the value of the phase delay approximating the fractional delay. A maximally-flat delay IIR fractional-delay filter can be obtained by the Thiran approximation. A simple and efficient method...
Conference Paper
Full-text available
The characteristics of a sound field at a location are determined by the arrival directions of the direct sound and the reflections, their amplitudes and time delays, which constitute the directional room responses (DRRs). While the sound field in a room can be modelled with a variety of acoustical modelling methods, there are relatively few record...
Conference Paper
Full-text available
Head-related transfer function (HRTF) filters are used in virtual auditory displays for the binaural synthesis of the direction of a sound source over headphones. Once low-order HRTF filters are designed, the interpolation of these filters becomes an important issue for the synthesis of moving sound sources. An HRTF filter interpolation method base...
Conference Paper
Positions of loudspeakers with respect to the listener play an important role in loudspeaker reproduction. When the listener is outside the sweet spot, one of the loudspeakers becomes dominant, decreasing the reproduction fidelity. Compensation of the time and level differences between the loudspeakers is possible if the positions of the loudspeake...
Conference Paper
Fidelity of spatial hearing effects generated by loudspeakers degrades outside the sweet spot. This paper proposes a method to analyze a sound scene created by stereo loudspeakers and modify it with the help of assistant headphones. Loudspeaker positions are found by analyzing B-format recordings at the listener position. This information is evalua...
Conference Paper
Impulse response of a room carries abstract information on the size and shape of that room. Acoustics research has focused on obtaining reflectograms from these physical characteristics using acoustical modelling techniques. However, estimation of the physical structure is also possible by analyzing the impulse responses for early reflections, echo...
Conference Paper
Full-text available
Three wavelet-based spectral smoothing techniques are presented in this paper as a pre-processing stage for head-related transfer function (HRTF) filter design. These wavelet-based methods include wavelet denoising, wavelet approximation, and redundant wavelet transform. These methods are used with time-domain parametric filter design methods to re...

Network

Cited By

Projects

Projects (2)
Project
www.iris-interaction.eu Marie Curie IAPP IRIS The overall goal of IRIS is to provide a natural interaction communication platform accessible and adapted for all users, particularly for people with speech impairments and elderly in indoor scenarios. Human-Computer interaction with this platform will adopt the principles of universal design and natural user interfaces such as speech, silent speech, gestures, tactile and haptic devices, pictograms, animated characters and personalized synthetic voices. The platform will provide a set of services that allow easy access to social networks, friends and remote family members, fighting social-exclusion of people with special needs or impairments. Application of these features will be performed in the context of serious games, virtual reality environments and assisted living scenarios. We will also explore the use of personalized avatars (that resemble with the user) in asynchronous human-human and human-machine communications, in situations where the user has lost his/her voice and in scenarios where it is not possible to have a video signal transmission due to low bandwidth or privacy reasons. Biometrics will complement the platform, in the sense that authentication and authorization are fundamental aspects for assuring access security to personal information in a natural way.