Modelling of Facial Images for Analysis of Recognition System

Face recognition is categorized as a biometric technology that employs the use of computer ability in image processing to detect and recognize human faces. Face recognition system has numerous applications for many purposes such as for access control, law enforcement and surveillance thus this system is dominant in present technology. Generally, face recognition system become more advance in term of the accuracy and implementation. However, there are a few parameters that effects the accuracy of recognition system for examples, the pose invariant, illumination effect, size of image and noise tolerance. Even though there are a number of systems were already available in the literature, the complete understanding of their performances are relatively limited. This is due to many systems focused on a narrow application band – therefore, a comprehensive analysis are needed in order to understand their performances leading to establishing the conditions for successful face recognition system. In this paper we developed a synthetic model to represent facial images to be used as a platform for performance analysis of facial recognition systems. The model includes 5 face types with the ability to vary all parameters that are affecting recognition performance – measurement noise, face size and face-background intensity differences. The model is important as it provide an avenue for performance analysis of facial recognition systems.

Localizing hot spots in Poisson radiation data matrices: nonnegative tensor factorization and phase congruency

Detecting and delineating hot spots in data from radiation sensors is required in applications ranging from monitoring large geospatial areas to imaging small objects in close proximity. This paper describes a computational method for localizing potential hot spots in matrices of independent Poisson data where, in numerical terms, a hot spot is a cluster of locally higher sample mean values (higher Poisson intensity) embedded in lower sample mean values (lower background intensity). Two numerical algorithms are computed sequentially for a 3D array of 2D matrices of gross Poisson counts: (1) nonnegative tensor factorization of the 3D array to maximize a Poisson likelihood and (2) phase congruency in pertinent matrices. The indicators of potential hot spots are closed contours in phase congruency in these matrices. The method is illustrated for simulated Poisson radiation datasets, including visualization of the phase congruency contours. The method may be useful in other applications in which there are matrices of nonnegative counts, provided that a Poisson distribution fits the dataset.

Switching median filter for suppressing multi-pixel impulse noise

This paper proposes a new switching median filter for suppressing multi-pixel impulse noise in X-ray images. A multi-pixel impulse is understood as a set of several neighboring pixels, the intensity of each significantly exceeds background intensity. Multi-pixel noise can occur, for example, due to the blooming effect, the reason being the limited value of pixel saturation capacity. This article defines the thresholds for the intensity increment relative to the eight immediate neighbors, above which the current pixel is processed by the median filter. The dependence of these thresholds on the number of pixels in an impulse is presented. The proposed algorithm is based on the median filtering process, which consists of several iterations. In this case, the filter has the smallest possible size, which minimizes image distortion during processing. In particular, to exclude a single-pixel impulse, pixel processing is turned on when intensity surge exceeds 3.5 with the grayscale value ranging from 0 to 1. At the same time, to exclude nine-pixel impulses, three iterations are required with the following thresholds: the first iteration with a threshold 2.0; the second iteration also with a threshold 2.0 and the third iteration with a threshold 3.5. The algorithm proposed was tested on real X-ray images corrupted by multi-pixel impulse noise. The algorithm is not only simple, but also reliable and suitable for real-time implementation and application. The efficiency of the technique is shown in comparison with other known filtering methods with respect to the degree of noise suppression. The main result of the testing is that only the proposed method allows excluding multi-pixel noise. Other advantage of the algorithm is its weak effect on the level of Gaussian noise leading to the absence of image blurring (or preserving image details) during processing.

3-D shape reconstruction of non-uniform reflectance surface based on pixel intensity, pixel color and camera exposure time adaptive adjustment

High dynamic range 3-D shape measurement is a challenge. In this work, we propose a novel method to solve the 3-D shape reconstruction of high-reflection and colored surfaces. First, we propose a method to establish a fast pixel-level mapping between the projected image and the captured image. Secondly, we propose a color texture extraction method using a black-and-white (B/W) camera and a pixel-level projection color adjustment method. Third, we give an optimal projection fringe modulation/background intensity ratio. Fourth, we propose a method for estimating the reflectivity of the object surface and ambient light interference, and a method for adjusting the projection intensity at the pixel level and a method for estimating the optimal exposure time. Experiments show that, compared with the existing methods, the proposed method not only can obtain high-quality captured images, but also has higher measurement efficiency and wider application range.

Application of Hilbert Analysis in Orthogonal Fourier Fringe-projection to Improve Object Shape Reconstruction -=SUP=-*-=/SUP=-

Three-dimensional (3D) measurement of an object is widely used in many fields including machine vision, quality control, robotics, medical diagnostics, and others. High-precision 3D surface topography is necessary for describing object shape accurately with high spatial resolution. A combined approach to improve 3D object shape recovery based on Fourier orthogonal fringe projection together with Hilbert transform is proposed and demonstrated. This new idea of combination is highly effective due to the suppressing of background intensity of the deformed fringe pattern while the zero spectrum is extracted precisely and easily. Removing the zero order component leads to increase the visualization and resolution of the measured object. Application of Hilbert processing for object shape recovery in orthogonal Fourier projection domain to improve 3D visualization has not been reported before. The processing framework of this strategy is described in detail. Validation of the proposed method is verified by experiments including visualization of objects with various shapes and sizes. A comparison between profilometry methods is also given which verify better performance in reconstruction of complex objects. 3D reconstruction of flow running at different speeds on a scattering medium with this combined approach is also demonstrated for the first time. Keywords: 3D shape measurements, orthogonal fringes, Fourier and Hilbert transform, image processing.

Lyman-α coupling and heating at Cosmic Dawn

The global 21-cm signal from the cosmic dawn is affected by a variety of heating and cooling processes. We investigate the impact of heating due to Lyman-α (Ly α) photons on the global 21-cm signal at cosmic dawn using an analytical expression of the spectrum around the Ly α resonance based on the so-called ‘wing approximation’. We derive a new expression for the scattering correction and for the first time give a simple close-form expression for the cooling due to injected Ly α photons. We perform a short parameter study by varying the Ly α background intensity by four orders of magnitude and establish that a strong Ly α background is necessary, although not sufficient, in order to reproduce the recently detected stronger-than-expected 21-cm signal by the EDGES Collaboration. We show that the magnitude of this Ly α heating is smaller than previously estimated in the literature by two orders of magnitude or more. As a result, even a strong Ly α background is consistent with the EDGES measurement. We also provide a detailed discussion on different expressions of the Ly α heating rate used in the literature.

Penetration of Carbon Nanotubes into the Retinoblastoma Tumor after Intravitreal Injection in LHBETATAG Transgenic Mice Reti-noblastoma Model

Purpose: To evaluate the penetration of carbon nanotubes (CNTs) throughout retinoblastoma in a transgenic mice model. Methods: CNTs functionalized with fluorescein isothiocyanate and targeting ligands biotin (CTN-FITC-Bio, 0.5mg/ml), or folic acid (CNT-FITC-FA, 0.5mg/ml) were injected into the vitreous of one eye of LHBETATAG transgenic mice. Other eye did not receive any injection and was used as control. Three mice were sacrificed at days 1, 2, and 3. Eyes were enucleated and stained with 4,6-diamidino-2-phenylindole. The sections were imaged by fluorescent microscope. The images were transformed into grey-scale in MATLAB for intensity analysis. Background intensity was normalized by marking squares outside the eyeball and using the mean intensity of these squares. Fluorescent intensity (FI) for each image was measured by calculating the intensity of a same-sized square within retinoblastoma. Results: Nine eyes of nine mice were included in each CNT-FITC-Bio and CNT-FITC-FA groups. The mean FI in CNT-FITC-Bio was 52.08 ± 6.33, 53.62 ± 9.00, and 65.54 ± 5.14 in days 1, 2, and 3, respectively. The mean FI in CNT-FITC-FA was 50.28 ± 7.37, 59.21 ± 6.43, and 58.38 ± 2.32 on days 1, 2, and 3, respectively. FI was significantly higher in eyes injected with CNT-FITC-Bio and CNT-FITC-FA compared to the control eyes (P = 0.02). There was no difference in FI between eyes with CNT-FITC-Bio and CNT-FITC-FA, and FI remained stable on days 1–3 in CNT-FITC-Bio, CNT-FITC-FA, and control eyes (P > 0.05). Conclusion: We observed higher FI in eyes with CNT-FITC-Bio and CNT-FITC-FA compared to control eyes, showing penetration of CNTs throughout retinoblastoma. CNTs can be a carrier candidate for imaging or therapeutic purposes in retinoblastoma.

Radial derivatives as a test of pre-big bang events on the Planck data

ABSTRACT Although the search for azimuthal patterns in cosmological surveys is useful to characterize some effects depending exclusively on an angular distance within the standard model, they are considered as a key distinguishing feature of some exotic scenarios, such as bubble collisions or conformal cyclic cosmology (CCC). In particular, the CCC is a non-stardard framework that predicts circular patterns on the cosmic microwave background intensity fluctuations. Motivated by some previous works that explore the presence of radial gradients, we apply a methodology based on the radial derivatives to the latest release of Planck data. The new approach allows exhaustive studies to be performed at all-sky directions at a healpix resolution of Nside = 1024. Specifically, two different analyses are performed focusing on weight functions in both small (up to a 5-deg radius) and large scales. We present a comparison between our results and those shown by An, Meissner & Nurowski (2017) and An et al. (2018). In addition, a possible polarization counterpart of these circular patterns is also analysed for the most promising case. Taking into account the limitations to characterize the significance of the results, including the possibility of suffering a look-elsewhere effect, no strong evidence of the kind of circular patterns expected from CCC is found in the Planck data for either the small or the large scales.

Pengaruh Tipe Industri, Ukuran Perusahaan, Latar Belakang Komite Audit, Intensitas Goodwill, dan Kualitas Audit Terhadap Kepatuhan Pengungkapan Goodwill Impairment Testing

The purpose of this study is to examine the effect of industrial type, company size, audit committee background, intensity of goodwill, and auditor quality on the disclosure of goodwill impairment testing compliance of firms listed on Indonesia Stock Exchange in the period of 2013-2017. It argues that manufacturing companies have higher operational complexity relative to other type of industry and thus disclose more information regarding firm’s activities, including information on goodwill impairment testing compliance. The results support the prediction. With regard to firm size, goodwill intensity, and auditor quality, the hypoyheses predict that these variables are positively associated with goodwill impairment testing compliance. The resultus support these predictions. Meanwhile, audit committee's background has no effect on the disclosure of goodwill impairment testing compliance. Abstrak Penelitian ini bertujuan untuk mengetahui pengaruh tipe industri, ukuran perusahaan, latar belakang komite audit, intensitas goodwill, dan kualitas auditor terhadap kepatuhan pengungkapan goodwill impairment testing pada perusahaan yang terdaftar di Bursa Efek Indonesia tahun 2013-2017. Tipe industri diprediksi mempengaruhi pengungkapan goodwill impairment testing karena perusahaan yang masuk kelompok industri manufaktur beroperasi dalam industri yang kompleks sehingga harus mengungkapkan lebih banyak informasi dibanding tipe industri lain, termasuk informasi tentang pengungkapan goodwill impairment testing. Ukuran perusahaan, intensitas goodwill, dan kualitas audit diprediksi berpengaruh positif terhadap kepatuhan pengungkapan goodwill impairment testing. Hasil pengujian juga mendukung prediksi tersebut. Sementara itu, Latar belakang komite audit tidak berpengaruh terhadap kepatuhan pengungkapan goodwill impairment testing.