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1.
AIP Conference Proceedings ; 2655, 2023.
Article in English | Scopus | ID: covidwho-20245510

ABSTRACT

The objective is to detect Novel Social Distancing using Local Binary Pattern (LBP) in comparison with Principal Component Analysis (PCA). Social Distance deduction is performed using Local Binary Pattern(N=20) and Principal Component Analysis(N=20) algorithms. Google AI open Images dataset is used for image detection. Dataset contains more than 10,000 images. Accuracy of Principal Component Analysis is 89.8% and Local Binary Pattern is 93.9%. There exists a statistical significant difference between LBP and PCA with (p<0.05). Local Binary Pattern appears to perform significantly better than Principal Component Analysis for Social Distancing Detection. © 2023 Author(s).

2.
Proceedings of the 10th International Conference on Signal Processing and Integrated Networks, SPIN 2023 ; : 806-810, 2023.
Article in English | Scopus | ID: covidwho-20238228

ABSTRACT

Crop image segmentation plays a key step in the field of agriculture. The crop images present near the environs have complex backgrounds and their grayscale histogram is mostly multimodal. Hence, multilevel segmentation of grayscale crop images may be helpful for better analysis. This paper proposed multilevel thresholding of grayscale crop images incorporated with minimum cross entropy as an objective function. The time complexity of this technique increases with the threshold levels. Hence, the coronavirus herd immunity optimizer (CHIO) has been amalgamated with the objective function. This technique improves the image's accuracy. The CHIO is a humanbased algorithm that separates the foreground and background efficiently with multiple thresholds value. The simulation has been performed on grayscale crop images. It is. compared with bacterial foraging algorithm (BFO), and beta differential algorithm (BDE) to validate the accuracy. The results validates that the proposed method outperforms BFO and BDE for grayscale crop images in terms of fidelity parameters. The qualitative and quantitative results evidence the proficiency of suggested method. © 2023 IEEE.

3.
Aims Mathematics ; 7(6):10495-10512, 2022.
Article in English | Web of Science | ID: covidwho-1810392

ABSTRACT

Under the background that Covid-19 is spreading across the world, the lifestyle of people has to confront a series of changes and challenges. This also presents new problems and requirements to automation facilities. For example, nowadays masks have almost become necessities for people in public places. However, most access control systems (ACS) cannot recognize people wearing masks and authenticate their identities to deal with increasingly serious epidemic pressure. Consequently, many public entries have turned to an attendant mode that brings low efficiency, infection potential, and high possibility of negligence. In this paper, a new security classification framework based on face recognition is proposed. This framework uses mask detection algorithm and face authentication algorithm with anti-spoofing function. In order to evaluate the performance of the framework, this paper employs the Chinese Academy of Science Institute of Automation-Face Anti-spoofing Datasets (CASIA-FASD) and Reply-Attack datasets as benchmarks. Performance evaluation indicates that the Half Total Error Rate (HTER) is 9.7%, the Equal Error Rate (EER) is 5.5%. The average process time of a single frame is 0.12 seconds. The results demonstrate that this framework has a high anti-spoofing capability and can be employed on the embedded system to complete the mask detection and face authentication task in real-time.

4.
Phlebology ; 37(1 SUPPL):23-24, 2022.
Article in English | EMBASE | ID: covidwho-1724206

ABSTRACT

Introduction, Objectives, and/or Purpose: Incompetent truncal and perforating veins of the legs contribute to a variety of conditions collectively called chronic venous insufficiency (CVI). Symptoms and signs of CVI adversely affect patient's quality-of-life. These can range from tired and heavy legs, through varicose veins, swollen ankles, fasciocutaneous damage all the way to leg ulceration. International guidelines recommend the treatment of venous reflux using endovenous thermal ablation as a first-line, and foam sclerotherapy as a second-line treatment. Both of these ablate the incompetent vein. There has been a push towards less invasive techniques, but most of these still involve endovenous cannulation. High-Intensity Focused Ultrasound (HIFU) is a completely non-invasive ablative technique. The HIFU technique uses to ultrasound systems within one machine. The first, a greyscale ultrasound with a colour flow capability, is used to identify the target vein and to target the focused ultrasound. The second is a conical focused ultrasound beam, that focuses on a point approximately 5 mm high by 3.6 mm circumference. In this focus area, temperatures can rise to 70-90°C. This is sufficient to ablate biological tissue. Objectives: (1) To assess the success of using HIFU for the treatment of incompetent truncal veins (GSV, SSV, AASV). (2) To assess the success of using HIFU for the treatment of incompetent perforator veins. (3) To determine the success of adjuvant foam sclerotherapy with of after HIFU, as a treatment protocol. Methods: A retrospective audit of 55 patients treated with HIFU using the Sonovein device (Theraclion, Paris, France) between May 2019 and September 2020 was performed. Due to the COVID-19 pandemic, and consequent travel restrictions and lockdowns, not all patients could return for follow-up DUS at the planned time intervals (1-2 weeks, 6- 8 weeks, 6 months, 1-year post-treatment). DUS outcome of the treated vein was graded: 1. complete success (complete atrophy of the target vein) 2. partial success (≥ 1 patent section;none giving rise to recurrent varicose veins / subclinical reflux not requiring treatment) 3. partial failure (≥ 1 patent section giving rise to significant recurrent varicose veins) 4. complete failure. Initially, we performed HIFU of incompetent veins and then completed the procedure with ultrasound-guided foam sclerotherapy. Later, the foamsclerotherapy was delayed and only used if required.We analysed the success rate of HIFU alone in those patients who had only HIFU treatment. In those who had additional foam sclerotherapy, we analysed the success rate of HIFU and foam sclerotherapy starting from the date of the foam sclerotherapy, regardless of whether it was performed on the same day as HIFU or subsequently. Results: Fifty patients (female:male 39:11) returned for at least one follow-up scan giving a 90.9% response rate for at least 1 scan. Due to the COVID-19 pandemic, and consequent travel restrictions and lockdowns, not all patients could return for follow-up DUS at planned time intervals (1-2 weeks, 6-8 weeks, 6 months, 1-year post-treatment). There were 78 legs treated, and 41 truncal veins and 146 incompetent perforator veins. Truncal veins: Twenty-nine patients (41 truncal veins in 35 legs) had at least one follow-up scan. Ten patients (15 truncal veins) had concurrent foam sclerotherapy, and nineteen patients (26 truncal veins) did not. Of these nineteen patients, seven patients (10 truncal veins) received foam sclerotherapy within one year of having HIFU treatment. Twelve patients (16 truncal veins) did not receive foam sclerotherapy at all. Those patients having HIFU only showed an 83.3% (15 out of 18) closure at 6- 8 weeks (Figure 1). The results for HIFU and foam sclerotherapy are shown in Figure 2. Despite difficulties in getting patients back for scans, closure rates of 83.3% and 100% were found between 9 and 12 months and over 12 months, respectively. Perforator veins: Forty-three patients (146 perforator veins in 68 legs) attended at least once. Suc essful ablation was seen in 88% at 6 months and 70% at one year in those not having foam sclerotherapy, and 83.3% and 100% in those having HIFU and foam sclerotherapy. Conclusions: High Intensity Focused Ultrasound (HIFU) is a new technique that can treat incompetent truncal and incompetent perforator veins extracorporeally. We have reported the one-year results of patients having either HIFU alone, or HIFU combined with ultrasound guided foam sclerotherapy. Allowances need to be made for the sporadic follow-up due to the COVID-19 pandemic, and also the fact that we changed our protocols of treatment as we got more experienced. Hence, even although we are reporting what is in effect the learning curve for this technique, the outcomes are not dissimilar from the early outcomes from endovenous thermal ablation. Increased speed of treatment with a corresponding reduction in the need of any local anaesthetic is being introduced, and further audits will be performed in the future to ensure the success rates are maintained or improved.

5.
Acs Applied Nano Materials ; : 10, 2022.
Article in English | Web of Science | ID: covidwho-1625984

ABSTRACT

The outbreak of SARS-CoV-2 has emphasized the value of point-of-care diagnostics, as well as reliable and cost-effective serological antibody tests, to monitor the viral spread and contain pandemics and endemics. Here, we present a three-dimensional (3D) nanofluidic device for rapid and multiplexed detection of viral antibodies. The device is made from poly(methyl methacrylate) and contains 3D fluidic channels with nanoscale topography variations on the millimeter length scale, enabled by combining gray-scale e-beam lithography and nanoimprint lithography. It works with capillary pumps only and does not require a complex microfluidic setup and pumps, which hinder the widespread usage of micro- and nanofluidic devices. The device is designed to size dependently immobilize particles from a multiparticle mixture at predefined positions in nanochannels, resulting in distinct trapping lines. We show that it can be used as an on-chip fluorescence-linked immunosorbent assay for highly specific and sensitive multiplexed detection of serological antibodies against different viral proteins. Further test flexibility is demonstrated by on-bead color multiplexing for simultaneous detection of IgG and IgM antibodies in convalescent human serum. The particle sorting is further leveraged to enable concurrent detection of anti-spike (SARS-CoV-2) and anti-hemagglutinin (influenza A) antibodies. The device's applications can be further extended to detect a large variety of diseases simultaneously in a reliable and straightforward manner.

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