Search results for "image"

High-Frame Rate Thermal Imagery of Strombolian Explosions: Implications for Explosive and Infrasonic Source Dynamics

2012

Digitaalisten kuvaväärennösten tunnistaminen JPEG-pakkausta hyödyntäen

2010

Digitaalisten valokuvien muokkaamisesta on tullut hyvin helppoa ja yleistä, mikä on nostanut esille huolen valokuvien uskottavuudesta. Ongelman ratkaisuksi on esitetty erilaisia tekniikoita, joilla valokuvien aitoutta voidaan arvioida. Tarkastelen tässä tutkielmassa niin sanottuja passiivisia tekniikoita, jotka eivät edellytä kuvasta minkäänlaista ennakkotietoa, kuten vesileimaa. Vertailen viittä tällaista tekniikkaa laatimani neljä kohtaa käsittävän kriteeristön pohjalta. Vertailtavia ominaisuuksia ovat tarkkuus, tunnistetut muokkaustyypit, rajoitukset sekä vakaus vastatoimia vastaan. Vertailu osoittaa, että eräs merkittävimmistä tekniikoiden ongelmista on niiden huono toleranssi kuvan häv…

Palermo e la guerra. Narrazioni: dalle immagini alle proposte di rinnovamento urbano

2023

The images of the bombing in Palermo in May 1943 are still etched in the collective memory. Some of the lacerations caused by the bombs are still clearly visible in the historic city centre, which has been the subject, since the post-war period, of numerous proposals that have remained in the drawer, images of an ethical and civil responsibility that has remained unheard. Old images of war and maps of ideas intersect in a history only apparently concluded in which they become generators of meaning and also bearers of messages relating to a desire for renewal.

Development of an immunochromatographic assay based on carbon nanoparticles for the determination of the phytoregulator forchlorfenuron

2013

Rapid analytical methods enabling the determination of diverse targets are essential in a number of research areas, from clinical diagnostics to feed and food quality and safety. Herein, the development of a quantitative immunochromatographic assay for the detection of the synthetic phytoregulator forchlorfenuron (CPPU) is described. The competitive lateral flow immunoassay (LFIA) was based on the immobilization onto a nitrocellulose membrane of an ovalbumin-CPPU conjugate (test line) and on the use of an immunodetection ligand consisting of carbon nanoparticles labeled with an anti-CPPU monoclonal antibody through interaction with a secondary antibody. The presence of CPPU in horticultural…

A new approach for geological faults detection

2004

This paper will introduce a new approach, mainly based on wavelets transform and mathematical morphology, for the detection of geological faults in satellite and aerial photos. This can be useful for territorial analysis, digital cartography and the use of geographical information systems. The proposed method is fast enough and unsupervised. Different techniques will be compared and some examples on real data will be presented to indicate the applicability of these methods.

English on the Finnish web pages : representations of Finnish towns and municipalities

2005

Webcam based display calibration

2012

International audience; We present an automatic method for measuring the tone response curve of display devices based on visual methods, where the eye is replaced by an end-user, uncalibrated camera, such as a webcam. Our approach compares a series of halftoned patches of known covering ratio with a continuous series of tone patches for each ratio. Both patches are shot by a camera that is used as a virtual eye to evaluate the luminance difference. By an iterative process, the continuous tone value is adjusted while compared with the perceived level of the halftoned patch. When the camera does not see any difference between the patches or a minimal difference, the luminance level of the con…

Oppressive Faces of Whiteness in Walter Mosley’s "Devil in a Blue Dress"

2018

Walter Mosley’s Devil in a Blue Dress contributes significantly to the literary debate on the definition of whiteness. The socio-historical construction of whiteness emerging from the novel is amplified by white imagery dovetailing with the claims made about white people directly. For the African American first person narrator, Easy Rawlins, living in post-World War II Los Angeles, whiteness mostly spells terror. The oppressive faces of whiteness consist in the following trajectories: property relations, economic exploitation, labour relations, the legal system, different miens of oppressive white masculinity denigrating blackness, spatial dynamics of post-World War II Los Angeles and the w…

Modelling and analysing oriented fibrous structures

2014

Abstract. A mathematical model for fibrous structures using a direction dependent scaling law is presented. The orientation of fibrous nets (e.g. paper) is analysed with a method based on the curvelet transform. The curvelet-based orientation analysis has been tested successfully on real data from paper samples: the major directions of fibrefibre orientation can apparently be recovered. Similar results are achieved in tests on data simulated by the new model, allowing a comparison with ground truth. peerReviewed

Characterization of three-dimensional microstructure of composite materials by X-ray tomography

2016

Analysis methods for X-ray microtomographic images of short fibre composite materials were developed. The methods enable estimation of microstructural properties of the material, e.g., aspect ratio and orientation of fibres. Being based on X-ray microtomography and image analysis, the methods are nondestructive and do not require user intervention. In particular, a method for determination of the aspect ratio of fibres was first developed. The method contains an assumption about similarity of the shape of the fibres. The assumption was relaxed in an improved method that can estimate cross-sectional properties of fibres, too, e.g., cross-sectional area. Additionally, the effect of finite ima…