Core-edge 2D fluid modeling of full tokamak discharge with varying magnetic equilibrium: from WEST start-up to ramp-down

In the present work we investigate for the first time the 2D fluid transport of the plasma in WEST during an entire discharge from the start-up to the ramp-down (shot #54487). The evolution of density profile, electron and ion temperatures together with the experimental magnetic equilibrium, total current and gas-puff rate is investigated. Comparisons with the interferometry diagnostic show a remarkable overall qualitative agreement during the discharge that can be quantitative at some locations in the plasma core. If at the onset of the X-points during the ramp-up the electron heat flux is dominant at the target, present results show that the ion heat flux becomes dominant during the stationary phase of the discharge. Using a simple model for erosion, present results assess the tungsten sputtering due to deuterium ions during the start-up and ramp-up phases of the discharge and confirms the need to consider full discharge simulation to accurately treat the W source of contamination. This work also demonstrates the interest of developing magnetic equilibrium free solver including efficient time integration to step toward predictive capabilities in the future for fusion operation.

A New Foreground-Background based Method for Behavior-Oriented Social Media Image Classification

Due to various applications, research on personal traits using information on social media has become an important area. In this paper, a new method for the classification of behavior-oriented social images uploaded on various social media platforms is presented. The proposed method introduces a multimodality concept using skin of different parts of human body and background information, such as indoor and outdoor environments. For each image, the proposed method detects skin candidate components based on R, G, B color spaces and entropy features. The iterative mutual nearest neighbor approach is proposed to detect accurate skin candidate components, which result in foreground components. Next, the proposed method detects the remaining part (other than skin components) as background components based on structure tensor of R, G, B color spaces, and Maximally Stable Extremal Regions (MSER ) concept in the wavelet domain. We then explore Hanman Transform for extracting context features from foreground and background components through clustering and fusion operation. These features are then fed to an SVM classifier for the classification of behavior-oriented images. Comprehensive experiments on 10-class datasets of Normal Behavior-Oriented Social media Image (NBSI) and Abnormal Behavior-Oriented Social media Image (ABSI) show that the proposed method is effective and outperforms the existing methods in terms of average classification rate. Also, the results on the benchmark dataset of five classes of personality traits and two classes of emotions of different facial expressions (FERPlus dataset) demonstrated the robustness of the proposed method over the existing methods.

Image Focus Enhancement Using Focusing Filter and DT-CWT Based Image Fusion

Combining multi-model images of the same scene that have different focus distances can produce clearer and sharper images with a larger depth of field. Most available image fusion algorithms are superior in results. However, they did not take into account the focus of the image. In this paper a fusion method is proposed to increase the focus of the fused image and to achieve highest quality image using the suggested focusing filter and Dual Tree-Complex Wavelet Transform. The focusing filter consist of a combination of two filters, which are Wiener filter and a sharpening filter. This filter is used before the fusion operation using Dual Tree-Complex Wavelet Transform. The common fusion rules, which are the average-fusion rule and maximum-fusion rule, were used to obtain the fused image. In the experiment, using the focus operators, the performance of the proposed fusion algorithm was compared with the existing algorithms. The results showed that the proposed method is better than these fusion methods in terms of the focus and quality.

A New Method for Detecting Altered Text in Document Images

As more and more office documents are captured, stored, and shared in digital format, and as image editing software are becoming increasingly more powerful, there is a growing concern about document authenticity. To prevent illicit activities, this paper presents a new method for detecting altered text in document images. The proposed method explores the relationship between positive and negative coefficients of DCT to extract the effect of distortions caused by tampering by fusing reconstructed images of respective positive and negative coefficients, which results in Positive-Negative DCT coefficients Fusion (PNDF). To take advantage of spatial information, we propose to fuse R, G, and B color channels of input images, which results in RGBF (RGB Fusion). Next, the same fusion operation is used for fusing PNDF and RGBF, which results in a fused image for the original input one. We compute a histogram to extract features from the fused image, which results in a feature vector. The feature vector is then fed to a deep neural network for classifying altered text images. The proposed method is tested on our own dataset and the standard datasets from the ICPR 2018 Fraud Contest, Altered Handwriting (AH), and faked IMEI number images. The results show that the proposed method is effective and the proposed method outperforms the existing methods irrespective of image type.

An Improved Object Detection Method using Feature Map Refinement and Anchor Optimization

Lower detection accuracy and insufficient detection ability for small objects are the main problems of the region-free object detection algorithm. Aiming at solving the abovementioned problems, an improved object detection method using feature map refinement and anchor optimization is proposed. Firstly, the reverse fusion operation is performed on each of the object detection layer, which can provide the lower layers with more semantic information by the fusion of detection features at different levels. Secondly, the self-attention module is used to refine each detection feature map, calibrates the features between channels, and enhances the expression ability of local features. In addition, the anchor optimization model is introduced on each feature layer associated with anchors, and the anchors with higher probability of containing an object and more closely match the location and size of the object are obtained. In this model, semantic features are used to confirm and remove negative anchors to reduce search space of the objects, and preliminary adjustments are made to the locations and sizes of anchors. Comprehensive experimental results on PASCAL VOC detection dataset demonstrate the effectiveness of the proposed method. In particular, with VGG-16 and lower dimension 300×300 input size, the proposed method achieves a mAP of 79.1% on VOC 2007 test set with an inference speed of 24.7 milliseconds per image.

A comparison of long-term efficacy of K-rod-assisted non-fusion operation and posterior lumbar interbody fusion for single-segmental lumbar disc herniation

BACKGROUND Since the development of internal fixation, posterior lumbar interbody fusion (PLIF) surgery has become the gold standard for the treatment of lumbar disc herniation. Although it has good short-term clinical efficacy, it can result in problems such as postoperative intractable lower back pain and degeneration of adjacent segments. K-rod-assisted non-fusion surgery for the treatment of lumbar disc herniation has also been proven to have clinical efficacy; however, its long-term effects have not been examined.AIMTo compare the long-term clinical efficacy of K-rod-assisted non-fusion operation to the clinical efficacy of PLIF in the management of single-segment lumbar disc herniation.METHODSThis study retrospectively analyzed 22 patients with lumbar disc (L4/5) herniation who underwent K-rod-assisted non-fusion operation (n=13) or PLIF (n=9) between December 2010 and December 2013 and were followed-up for more than 5 years. Clinical outcomes were evaluated by the Oswestry Disability Index (ODI), pain Visual Analogue Score (VAS), and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). Imaging evaluations included adjacent segmental intervertebral height, range of motion (ROM) of the vertebrae, incidence of lumbar instability, spino-pelvic parameters, Pfirrmann grading, Modic changes, and University of California Los Angeles (UCLA) grading.RESULTS Clinical outcomes, namely operation times (110.5±11.15 min vs. 134.44±12.36 min, P <0.05) and blood loss (59.2±7.03 ml vs. 80.0±8.66 ml, P <0.05), were significantly reduced in the K-rod group compared to the PLIF group. At the last follow-up, the clinical outcomes of the K-rod group were improved compared to those of the PLIF group as observed by the VAS score (2.1±0.9 vs. 3.0±0.7, P <0.05), JOABPEQ (26.7±1.1 vs. 25.2±1.5, P <0.05), and ODI (21.0±3.7 vs. 28.4±6.9, P <0.05). Imaging outcomes at the last follow-up indicated that the loss of height in the L3/4 intervertebral space (0.4±0.9 mm vs. 1.5±0.7 mm, P <0.05) and L5/S1 intervertebral space (0.2±0.5 mm vs. 1.8±1.7 mm, P <0.05), the ROM of L3/4 (4.9±2.0 vs. 8.8±2.4, P <0.05), the ROM of L5/S1 (5.7±1.7 vs. 8.6±1.2, P <0.05), and the incidence of adjacent segment degeneration (7.7% vs. 38.9%, P <0.05) in the PLIF group were significantly higher than those in the K-rod group. According to Pfirrmann grading, Modic changes, and UCLA grading, the incidence of adjacent segment degeneration was 55.6% in the PLIF group and 15.4% in the K-rod group. Changes in spino-pelvic parameters between the two groups were as follows: pelvic index remained unchanged, pelvic tilt angle increased, and lumbar lordosis and sacral slope decreased.CONCLUSIONCompared to PLIF, single-segment lumbar disc herniation using K-rod-assisted non-fusion surgery resulted in better long-term clinical efficacy. Our results demonstrate that this procedure can delay adjacent segment degeneration after lumbar surgery.

“Nature Abhors a Vaccuum”: Invagination of the Small Intestine into the Lumbar Disc Space After a Spinal Fusion Operation

A 77-year-old woman having back pain due to an L2 vertebral body compression fracture took a lumbar spine magnetic resonance imaging (MRI). In MRI, in addition to the L2 vertebral body fracture, invagination of the small intestine into the intervertebral disc space at L5-S1 was found by chance. On a lateral lumbar spinal X-ray, the lordotic angle was markedly increased at the L5-S1 level. Additionally, the L5-S1 disc space had widened. These X-ray findings indicate the segmental instability at L5-S1. The spinal fusion operation on L3-4-5 seems to have resulted in overt mechanical loading on the inferior spinal segment (L5-S1). We think the instability damaged the anterior longitudinal ligament and caused a tear in the anterior portion of the annulus fibrosus. The defect in the L5-S1 intervertebral disc after the tear would have caused the vacuum, which is presumed to have pulled the patient’s small intestine into the empty space within the L5-S1 intervertebral disc. Although intervertebral invagination of intra-abdominal structures is not common, clinicians should be aware of the possibility of this complication in patients who have spinal segmental instability.

Outcomes of a retrospective study on sustained release betamethasone for transient radicular symptoms in patients after Transforaminal Lumbar Interbody Fusion operation

Objective To observe the efficacy and Complications of gelatin sponge sustained release betamethasone for transient radicular symptoms in patients after TLIF operation.Method A total of 218 patients with single-level LDH were retrospectively analyzed from March 2017 to July 2019. Patients were divided into observation group and control groups according to different approach.Clinical data such as lasegue sign, VAS score, ODI index were compared, the data analyzed by SPSS 24.0 statistical software.Results 186 patients were finally included. The observation group has significantly different between the control groups(P<0.05)at five days after surgery. And there was no significant difference in VAS and ODI between the four groups (P > 0.05)at 2-3 months after surgery, . There was no significant difference in blood glucose before and after operation in the observation group(P > 0.05), and numeration of leukocyte in the four groups was significantly higher than before operation (P<0.05), but there was no statistically significant difference between the four groups before and after operation (P > 0.05). The patients in the four groups had basically the same satisfaction with the final efficacy (> 90%) . In addition, there was the same Complications in four groups(eg.postoperative nausea, vomiting and other complications.)Conclusion the use of gelatin sponge sustained-release steroids and other mixed solutions can significantly relieve transient radicular symptoms after TLIF operation,and does not influence the occurrence of postoperative complications.