Dense Haze Removal by Nonlinear Transformation Agrawal, Subhash Chand; Jalal, Anand Singh
IEEE transactions on circuits and systems for video technology,
02/2022, Volume:
32, Issue:
2
Journal Article
Peer reviewed
Images captured in hazy or foggy weather conditions, suffer from various problems, such as limited visibility, low contrast, color distortions. These images are used in many computer vision ...applications, such as video surveillance, transportation, remote sensing. The elimination of the haze effect from these images is essential to ensure the perfect working of these applications. The degradation of a captured image is expressed by the physical model of hazy image formation. The physical model requires the estimation of transmission to restore a haze-free image, which is one of the most important parameters of single image dehazing (SID). Due to the ill-posed nature of SID, lots of priors/assumptions have been used. However, traditional methods fail when these priors do not hold, especially for varying haze concentrations, which lead to many issues such as incomplete haze removal or over enhancement in long-range regions. In this paper, a single image dehazing method based on a superpixel and nonlinear transformation is proposed. The proposed method transforms the minimum filtering on superpixels of a hazy image into the minimum filtering on superpixels of a haze-free image using nonlinear transformation. The nonlinear transformation prevents over enhancement in the long-range regions, while the superpixels reduce the halo artifacts in the dehazed image. The experimental results on challenging real hazy images, dense-hazy images, and synthetic images have proved that a combination of nonlinear transformation and superpixels provide the strength to the proposed method. The obtained dehazed results are evaluated qualitatively and quantitatively and it is found that the proposed method has tremendous performance as compared to state-of-the-art dehazing approaches.
Following the discovery of ruins of Nalanda Mahavihara, multiple questions were raised, a plethora of speculations were made, and stifling conjectures were advanced about the origin, evolution, and ...decline of the greatest academic institution of the world. Multiple excavations through the years have yielded a lot of information about the structures and functions of the Mahavihara, which are well corroborated by the literary evidences. Though the bulk of the monastic sites is still not excavated due to habitation over the mounds and other factors. Still, scattered surveys and excavations have provided information revealing enough to facilitate a re-examination of the hypothesis developed on Nalanda. The knowledge furthered by the excavations and supplemented by the epigraphic and literary sources has raised many questions about some of the established myths related to the foundation/founder of the Mahavihara, the nomenclature of Nalanda, and origin of the structural form of Nalanda seals. Could Śakraditya be the founder? Was Nalanda the first Mahavihara? This paper examines these questions with the support of new archaeological sources and literary arguments.
The advent of tyrosine kinase inhibitors (TKIs) targeted therapy revolutionized the treatment of chronic myeloid leukemia (CML) patients. However, cardiotoxicity associated with these targeted ...therapies puts the cancer survivors at higher risk. Ponatinib is a third-generation TKI for the treatment of CML patients having gatekeeper mutation T315I, which is resistant to the first and second generation of TKIs, namely, imatinib, nilotinib, dasatinib, and bosutinib. Multiple unbiased screening from our lab and others have identified ponatinib as most cardiotoxic FDA approved TKI among the entire FDA approved TKI family (total 50+). Indeed, ponatinib is the only treatment option for CML patients with T315I mutation. This review focusses on the cardiovascular risks and mechanism/s associated with CML TKIs with a particular focus on ponatinib cardiotoxicity. We have summarized our recent findings with transgenic zebrafish line harboring BNP luciferase activity to demonstrate the cardiotoxic potential of ponatinib. Additionally, we will review the recent discoveries reported by our and other laboratories that ponatinib primarily exerts its cardiotoxicity via an off-target effect on cardiomyocyte prosurvival signaling pathways, AKT and ERK. Finally, we will shed light on future directions for minimizing the adverse sequelae associated with CML-TKIs.
•Radiation and chemotherapy-induced cardiotoxicity is well established.•However, kinase inhibitors (KIs)-induced cardiotoxicity is less recognized.•Multiple labs have identified ponatinib as most cardiotoxic FDA approved KI.•Ponatinib is the only treatment option for CML patients with T315I mutation.•Herein, ponatinib and other CML KIs-induced cardiotoxicity is discussed.
Images acquired in poor weather conditions (haze, fog, smog, mist, etc
.
) are often severely degraded. In the atmosphere, there exists two types of particles: dry particles (dust, smoke, etc
.
) and ...wet particles (water droplets, rain, etc.) Due to the scattering and absorption of these particles, various adverse effects, including reduced visibility and contrast, color distortions, etc
.
are introduced in the image. These degraded images are not acceptable for many computer vision applications such as smart transportation, video surveillance, weather forecasting, remote sensing, etc
.
The computer vision task associated with the mitigation of this effect is known as image dehazing. A high-quality input image (haze-free) is required to ensure the accurate working of these applications, supplied by image dehazing methods. The haze effect in the captured image is dependent on the distance from the observer to the scene. Besides, the scattering of particles adds non-linear and data-dependent noise to the captured image. Single image dehazing utilizes the physical model of hazy image formation in which estimation of depth or transmission is an important parameter to obtain a haze-free image. This review article groups the recent dehazing methods into different categories and elaborates the popular dehazing methods of each category. This category-wise analysis of different dehazing methods reveals that the deep learning and the restoration-based methods with priors have attracted the attention of the researchers in recent years in solving two challenging problems of image dehazing: dense haze and non-homogeneous haze. Also, recently, hardware implementation-based methods are introduced to assist smart transportation systems. This paper provides in-depth knowledge of this field; progress made to date and compares performance (both qualitative and quantitative) of the latest works. It covers a detailed description of dehazing methods, motivation, popular, and challenging datasets used for testing, metrics used for evaluation, and issues/challenges in this field from a new perspective. This paper will be useful to all types of researchers from novice to highly experienced in this field. It also suggests research gaps in this field where recent methods are lacking.
The paper deals with the study of the hilltop Buddhist complex known as Giriyaka at Rajgir, Nalanda district of Bihar, India. This site was first noticed by the archaeologists of the colonial period. ...A M Broadley, Francis Buchanan, Malcom Kittoe, Alexander Cunningham, etc., surveyed and explored the site to identify Buddhist monastic artefacts and remains. The archaeological landscape of Giriyaka offers multi phases linear development of Buddhism since the NBPW period. Cunningham articulates it as Indasala-guha where the Buddha preached the Sakkapaňňa Sutta but it was vehemently opposed by Broadley and others. The archaeological remains include well-preserved stūpas, water reservoir, monasteries, and seals. The close examination of remains at Giriyaka provides new facets into antiquity, development, and continuity of Buddhism from the age of the Buddha to the early medieval period. An enigmatic structure located on a steep hill protected by parapet corresponds to a glimpse of a well-developed sacred space of stūpas and viharas. The caves in the surrounding hills show interesting but intricate information. The structural remains also indicate that the Giriyaka was the first fully evolved hilltop monastery in the Magadha region.
The automatic narration of a natural scene is an important trait in artificial intelligence that unites computer vision and natural language processing. Caption generation is a challenging task in ...scene understanding. Most of the state-of-the-art methods are using deep convolutional neural network models to extract visual features of the entire image, based on which the parallel structures between images and sentences are exploited using recurrent neural networks for image captioning. However, in such models, only visual features are exploited for caption generation. This work investigated that fusion of text available in an image can give more fined-grained captioning of a scene. In this paper, we have proposed a model which incorporates a deep convolutional neural network and long short-term memory to boost the accuracy of image captioning by fusing text feature available in an image with the visual features extracted in state-of-the-art methods. We have validated the effectiveness of the proposed model on the benchmark datasets (Flickr8k and Flickr30k). The experimental outcomes illustrate that the proposed model outperformed the state-of-the-art methods for image captioning.
Background
The ideal management of common bile duct (CBD) stones associated with gall stones is a matter of debate. We planned a meta-analysis of randomized trials comparing single-stage laparoscopic ...CBD exploration and cholecystectomy (LCBDE) with two-stage preoperative endoscopic stone extraction followed by cholecystectomy (ERCP + LC).
Methods
We searched the Pubmed/Medline, Web of science, Science citation index, Google scholar and Cochrane Central Register of Controlled trials electronic databases till June 2017 for all English language randomized trials comparing the two approaches. Statistical analysis was performed using Review Manager (RevMan) Computer program, Version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014 and results were expressed as odds ratio for dichotomous variables and mean difference for continuous.
p
value ≤ 0.05 was considered significant. Trial sequential analysis (TSA) was performed using TSA version 0.9.5.5 (Copenhagen: The Copenhagen Trial Unit, Centre for Clinical Intervention Research, 2016). PROSPERO trial registration number is CRD42017074673.
Results
A total of 11 trials were included in the analysis, with a total of 1513 patients (751-LCBDE; 762-ERCP + LC). LCBDE was found to have significantly lower rates of technical failure OR 0.59, 95% CI (0.38, 0.93),
p
= 0.02 and shorter hospital stay MD − 1.63, 95% CI (− 3.23, − 0.03),
p
= 0.05. There was no significant difference in mortality OR 0.37, 95% CI (0.09, 1.51),
p
= 0.17, morbidity OR 0.97, 95% CI (0.70, 1.33),
p
= 0.84, cost MD − 379.13, 95% CI (− 784.80, 111.2),
p
= 0.13 or recurrent/retained stones OR 1.01, 95% CI (0.38, 2.73),
p
= 0.98. TSA showed that although the Z-curve crossed the boundaries of conventional significance, the estimated information size is yet to be achieved.
Conclusions
Single-stage LCBDE is superior to ERCP + LC in terms of technical success and shorter hospital stay in good-risk patients with gallstones and CBD stones, where expertise, operative time and instruments are available.
Many computer vision-based techniques utilize semantic information i.e. scene text present in a natural scene for image analysis. Subsequently, in recent times researchers pay more attention to key ...tasks such as scene text detection, recognition, and end-to-end system. In this survey, we have given a comprehensive review of the recent advances on these key tasks. The review focused firstly on the traditional methods and their categorization, also show the evolution of scene text detection, recognition methods, and end-to-end systems with their pros and cons. Secondly, this survey focuses on the latest state-of-the-art (SOTA) methods based on transfer learning and additionally do the extension of scene text reading system i.e. salient text detection, text or non-text image classification, a fusion of scene text in vision and language, etc. After that, we have done a performance analysis on various SOTA methods on the various key issues and techniques. Finally, we discuss the various evaluation metrics and standard dataset on which the various SOTA methods of scene text detection is investigated and compared.
The unprecedented increase in the Sea Surface Temperature (SST) in the warming climate yield stress to the system and pose severe threats to the marine ecosystem. Marine Heatwaves (MHWs) and Marine ...Cold Spells (MCSs) are two extreme events related to SST variability. For better management of ocean productivity, marine ecosystem, marine services, and fisheries, the understanding of seasonal discrepancies rather than annual documentation of MHWs and MCSs metrics is more utilitarian. This study documents the decadal changes in the MHWs and MCSs over the Tropical Indian Ocean (TIO) for all seasons. Additionally, highly intense events (based on intensity and duration) are identified and demonstrate the associated drivers. During the past two decades (1982–1990, 1991–2000), the MCSs were more frequent than MHWs in every season. However, in the recent two decades (2001–2010, 2011–2020), TIO become more prone to MHWs with considerably more frequent and prolonged events in JJAS months. Moreover, MCSs are disappearing from the TIO. It was noted that the choice of baseline period has an impact on the magnitude of MHWs and MCSs changes, but the spatial pattern (regions with high/low magnitude MHWs and MCSs) stays fairly constant in all baseline period sensitivity checks. The investigation of highly intense events reveals that MHWs and MCSs are produced and sustained by the same drivers when they are at their opposing edges. In general, the coherence effort from winds, net heat fluxes (shortwave radiation, longwave radiation, latent heat flux, and sensible heat flux), mixed level depth, and mean sea level pressure contribute to the genesis of seasonal MHWs or MCSs events. Additionally, in some cases, a single driver (e.g., wind) may also play a crucial role in these extreme events. The remote climate modes of variability, such as El Niño–Southern Oscillation, also contribute significantly to the MHWs and MCSs. El Niño (La Niña) events not only increase the spatial coverage of MHWs (MCSs) but also increases the intensity.
The frequency and intensity of marine heatwaves (marine cold spell) has increased (decreased) in the recent decades, even shifting dominantly from colder to warmer events which attributed by wind speed and net heat flux. Highly exaggerated marine heatwaves are associated with El Niño while Marine cold spells are connected to La‐Niña events.
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