Image-based Early Detection System for Wildfires

Wildfires are a disastrous phenomenon which cause damage to land, loss of property, air pollution, and even loss of human life. Due to the warmer and drier conditions created by climate change, more severe and uncontrollable wildfires are expected to occur in the coming years. This could lead to a global wildfire crisis and have dire consequences on our planet. Hence, it has become imperative to use technology to help prevent the spread of wildfires. One way to prevent the spread of wildfires before they become too large is to perform early detection i.e, detecting the smoke before the actual fire starts. In this paper, we present our Wildfire Detection and Alert System which use machine learning to detect wildfire smoke with a high degree of accuracy and can send immediate alerts to users. Our technology is currently being used in the USA to monitor data coming in from hundreds of cameras daily. We show that our system has a high true detection rate and a low false detection rate. Our performance evaluation study also shows that on an average our system detects wildfire smoke faster than an actual person.Comment: Published in Tackling Climate Change with Machine Learning workshop, Thirty-sixth Conference on Neural Information Processing Systems (NeurIPS 2022

The Lick AGN Monitoring Project 2016 : dynamical modeling of velocity-resolved Hβ lags in luminous Seyfert galaxies

K.H. acknowledges support from STFC grant ST/R000824/1.We have modeled the velocity-resolved reverberation response of the Hβ broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitoring Project 2016 sample, drawing inferences on the geometry and structure of the low-ionization broad-line region (BLR) and the mass of the central supermassive black hole. Overall, we find that the Hβ BLR is generally a thick disk viewed at low to moderate inclination angles. We combine our sample with prior studies and investigate line-profile shape dependence, such as log10(FWHM/σ), on BLR structure and kinematics and search for any BLR luminosity-dependent trends. We find marginal evidence for an anticorrelation between the profile shape of the broad Hβ emission line and the Eddington ratio, when using the rms spectrum. However, we do not find any luminosity-dependent trends, and conclude that AGNs have diverse BLR structure and kinematics, consistent with the hypothesis of transient AGN/BLR conditions rather than systematic trends.Publisher PDFPeer reviewe

The Lick AGN Monitoring Project 2016: Dynamical Modeling of Velocity-Resolved H\b{eta} Lags in Luminous Seyfert Galaxies

We have modeled the velocity-resolved reverberation response of the H\b{eta} broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitioring Project 2016 sample, drawing inferences on the geometry and structure of the low-ionization broad-line region (BLR) and the mass of the central supermassive black hole. Overall, we find that the H\b{eta} BLR is generally a thick disk viewed at low to moderate inclination angles. We combine our sample with prior studies and investigate line-profile shape dependence, such as log10(FWHM/{\sigma}), on BLR structure and kinematics and search for any BLR luminosity-dependent trends. We find marginal evidence for an anticorrelation between the profile shape of the broad H\b{eta} emission line and the Eddington ratio, when using the root-mean-square spectrum. However, we do not find any luminosity-dependent trends, and conclude that AGNs have diverse BLR structure and kinematics, consistent with the hypothesis of transient AGN/BLR conditions rather than systematic trends

The Lick AGN Monitoring Project 2016 : velocity-resolved Hβ lags in luminous Seyfert galaxies

Funding: K.H. acknowledges support from STFC grant ST/R000824/1.We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on the 3 m Shane telescope at Lick Observatory from April 2016 to May 2017. Targetingactive galactic nuclei (AGN) with luminosities of λLλ(5100 Å) ≈ 1044 erg s−1 and predicted Hβ lags of∼ 20–30 days or black hole masses of 107–108.5 M⊙, our campaign probes luminosity-dependent trends in broad-line region (BLR) structure and dynamics as well as to improve calibrations for single-epoch estimates of quasar black hole masses. Here we present the first results from the campaign, including Hβ emission-line light curves, integrated Hβ lag times (8–30 days) measured against V -band continuum light curves, velocity-resolved reverberation lags, line widths of the broad Hβ components, and virial black hole mass estimates (107.1–108.1 M⊙). Our results add significantly to the number of existing velocity-resolved lag measurements and reveal a diversity of BLR gas kinematics at moderately high AGN luminosities. AGN continuum luminosity appears not to be correlated with the type of kinematics that its BLR gas may exhibit. Follow-up direct modeling of this dataset will elucidate the detailed kinematics and provide robust dynamical black hole masses for several objects in this sample.Publisher PDFPeer reviewe

Perceptions of components of the special education system in Korea.

This study surveyed the perceptions of educators in Korean special schools regarding the current status and issues in eight components of the special education system. The eight components of a special education system selected were: philosophy and fundamental practices, identification and evaluation, instruction and related services, personnel, parents and the public, organization, funding, and facilities. A survey instrument was used to obtain information from 70 principals and 192 teachers, with a response rate of 58 (83%) and 156 (81%), respectively. A mean score of responses to each questionnaire item in each component of the special education system was calculated to rate the perceptions of all subjects. The perceptions of special educators were negative toward the status of special education in many items of eight components of the system. The ratings were compared using a t-test or analysis of variance to analyze statistical differences by such variables as position of special educator (principal and teacher), foundation of special school (public and private), and disability areas of special educator (visual, hearing, mental, and physical impairments). The ratings of special educators on the eight system components were statistically significant in four components, according to the foundation of the special schools. As a whole, the perceptions of special educators did not reveal many significant differences by the variables of position and disability specialty areas. Critical issues to be resolved in the future were identified and discussed. Recommendations were made for future development of special education in Korea

An affine symmetric image model and its applications

Natural images contain considerable redundancy, some of which is successfully captured using recently developed directional wavelets. In this paper, an affine symmetric image model is considered. It provides a flexible scheme to exploit geometric redundancy. A patch of texture from an image is rotated, scaled and sheared to approximate other similar parts in the image, revealing the self-similarity relation. The general scheme is derived as follows. A texture model is required that identifies structural patterns. Then the affine symmetry is exploited between structural textures at a local level, the objective being to find the minimum residual error by estimating the affine transform relating two patches of texture. Having developed a local model, the methodology is extended to the whole image to estimate the global affine relation. This global model is further developed in a multiresolution framework for multiscale analysis, by which the self similarity of the image is exploited across space and scale. The multiresolution model can be applied to a series of practical problems. Experimental evaluation demonstrates the effectiveness of the approach in affine invariant texture segmentation and image approximation

Local affine image matching and synthesis based on structural patterns

A general purpose block-to-block affine transformation estimator is described. The estimator is based on Fourier slice analysis and Fourier spectral alignment. It shows encouraging performance in terms of both speed and accuracy compared to existing methods. The key elements of its success are attributed to the ability to: 1) locate an arbitrary number of affine invariant points in the spectrum that latch onto significant structural features; 2) match the estimated invariant points with the target spectrum by the slicewise phase-correlation; and 3) use affine invariant points to directly compute all linear parameters of the full affine transform by spectral alignment. Experimental results using a wide range of textures are presented. Potential applications include affine invariant image segmentation, registration, affine symmetric image coding, and motion analysis

Affine symmetry and applications in image processing

Natural images have a great deal of self-similarity in a sense that a part of an image can replace another part with a slight deformation. We employ affine symmetry to address the self-relationship, i.e. rotation, scaling, shearing and translation. In this report, various applications are presented exploiting affine symmetry in images. Firstly, an image coding technique is discussed that uses affine symmetric redundancy between blocks. This poses an interesting approach as opposed to the recent directional Wavelet based trend. Experiments show visually acceptable picture quality at low bitrates. Secondly, a segmentation algorithm is presented that analyses images in a similar manner to the image coding application. The algorithm uses a directional shape extracted from the local Fourier spectrum. From the obtained shape, a feature is extracted using the affine-invariant Fourier descriptor. Experimental evaluation on structural textures shows encouraging results and application on natural images demonstrates identification of texture objects. Thirdly, a denoising technique that combines Independent Component Analysis (ICA) and the Multiresolution Fourier Transform (MFT) is presented. This technique inherits the ability to find bases adaptively from given data using ICA and the computational efficiency of the MFT. Another denoising approach is demonstrated that utilises the shape information from the segmentation algorithm as a thresholding mechanism. The experimental results are promising even compared with the recent directional transform such as the Curvelet. Lastly, future research directions are briefly mentioned

Video compression : wavelet based coding and texture synthesis based coding

This report introduces the emerging Wavelet-based video coding system. Inefficiency of the block-based motion estimation in context of the wavelet coder is discussed in comparison to the mesh-based approach. A progressive mesh refinement technique using multiple layers is proposed also a fast motion estimation based on the redundant wavelet is presented that outperforms a full-search motion estimation in both computation requirement and motion accuracy. Finally, the two-component texture synthesis algorithm is explored in connection with recently developed technique using GMM and LM to model and estimate transformation. The texton and ICA is briefly explained as alternatives

Improved schemes for inter-frame coding in the H.264/AVC standard

An efficient algorithm for inter-frame coding in the H.264/AVC standard is extended to provide more significant speedup in computational performance for sequences containing high spatial correlation and motion. The proposed scheme features a more sophisticated search process and robust predictions to achieve better PSNR-rate performance for a large range of compression levels. Extensive simulation results demonstrate speedups of between 41% and 68%, with no noticeable deterioration in picture quality or compression ratio, even for the coding of complex video sequences