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3. Prediction of Hydrate Phase Equilibrium of Condensate Gas with High CO2 Content

Author

Jing, Pengcheng, Yu, Changhong, Xia, Yuxiang, Liang, Youran, Ma, Wang, Liu, Hongtao, Chen, Litao, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, Sun, Baojiang, editor, Sun, Jinsheng, editor, Wang, Zhiyuan, editor, Chen, Litao, editor, and Chen, Meiping, editor

Published
2024
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4. Study on Methane Hydrate Detection in Gas Containing Oil Pipelines by Electrical Resistivity Test

Author

Liang, Youran, Zhang, Yuhang, Ma, Wang, Xia, Yuxiang, Jing, Pengcheng, Yu, Changhong, Xiao, Kai, Chen, Litao, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, Sun, Baojiang, editor, Sun, Jinsheng, editor, Wang, Zhiyuan, editor, Chen, Litao, editor, and Chen, Meiping, editor

Published
2024
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5. Experimental Investigation on the Effect of AA + PVCap + MeOH Compound to Methane Hydrate Agglomeration in Water

Author

Ma, Wang, Lv, Fengjun, Chen, Litao, Liang, Youran, Yu, Changhong, Jing, Pengcheng, Xia, Yuxiang, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, Sun, Baojiang, editor, Sun, Jinsheng, editor, Wang, Zhiyuan, editor, Chen, Litao, editor, and Chen, Meiping, editor

Published
2024
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19. Mammography machine compression paddle movement and observer performance analysis

Author

Ma, Wang Kei

Subjects
618.1
Abstract

Full field digital mammography (FFDM) was introduced into the United Kingdom (UK) as a replacement for screen-film mammography (SFM) in 2005. Since then, individual breast screening centres have begun to report blurred images through local audits. Blurring was probably present in SFM as well, however the improvement in contrast resolution in FFDM may have made it more apparent. The sources of blurring include improper imaging techniques, patient movement caused by breathing and heart motion,the viscoelastic motion of the breast, and paddle motion. This thesis aims to test the hypothesis that paddle motion might cause image blur. It investigates whether blurring can be detected visually on technical review monitors and reporting grade monitors. The thesis presents a method to minimise paddle motion during X-ray exposure. Six papers have been published. Two of these (papers 1 and 2) investigated paddle displacement using linear potentiometers. Three investigated the influence of paddle motion on image quality. Paper 3 investigated whether paddle motion can cause image blur; paper 4 determined the minimum amount of simulated motion required for the visual detection of blurring; and paper 5 evaluated the practitioner's ability to identify blurring on monitors with different resolutions (2.3 MP and 5 MP). The final research paper (paper 6) investigated a way to reduce paddle displacement settling time; this involved the use of a closed-loop control system. Results: In papers 1 and 2 paddle displacement followed a bi-exponential function with a settling time of approximately 40 s. The use of average paddle displacement to estimate the amount of paddle motion would underestimate the worst case of the three different runs of the experiment. The estimated paddle motion would be greatly reduced if the time of exposure is delayed from 5 to 10 s. In paper 3 all metal ball bearings shown increased in diameters and the range of magnification varied from 1.04 to 1.21. T-test results shown that there was a significant difference (p < 0.05) in the ball bearing diameters between the intensity thresholding and the edge detection methods for all paddle/ compression force combinations. The ball bearing diameters calculated by the intensity thresholding method had higher variability than the edge detection method. In paper 4 the soft-edged mask method best represented the physical process that caused the blurring effect and was chosen as the standard simulation approach for motion blurring. The ratio between the vertical paddle motion and the horizontal breast motion estimated by the mathematical model is approximately 1:0.3. In paper 5 the angular size calculation shown that for a viewing distance of 75 cm the screen resolution for 5 MP and 12 MP monitors was better than the observer eyes' resolution. For a viewing distance of 30 cm the observer eyes' resolution was better than the screen resolution for 2.3 MP, 5 MP and 12 MP monitors. Among all three monitors, image displayed on the 12 MP monitor has the lowest loss in image quality after interpolation. In paper 6 the simulation results shown that force overshoot is possible for position control system. Force overshoot occurred almost instantaneously for step input and its magnitude is about 10 times larger than the ramp input. Force overshoot and steadystate error can be eliminated by the use of force control system. Conclusion: The magnitude of calculated paddle motion is much lower than the minimum amount of simulated motion required for the visual detection of blurring. Mathematical models have shown that vertical paddle motion caused a smaller horizontal breast displacement when compressed. Therefore, there is no sufficient evidence to support the hypothesis that paddle motion is a cause of image blurring in FFDM.

Published
2021

23. Diagnostic value and key features of computed tomography in Coronavirus Disease 2019.

Author

Li, Bingjie, Li, Xin, Wang, Yaxuan, Han, Yikai, Wang, Yidi, Wang, Chen, Zhang, Guorui, Jin, Jianjun, Jia, Hongxia, Fan, Feifei, Ma, Wang, Liu, Hong, and Zhou, Yue

Subjects
Lung, Humans, Pneumonia, Viral, Coronavirus Infections, Severe Acute Respiratory Syndrome, Disease Progression, Diagnosis, Differential, Tomography, X-Ray Computed, Radiography, Thoracic, Clinical Laboratory Techniques, Nucleic Acid Amplification Techniques, Pandemics, Betacoronavirus, COVID-19, SARS-CoV-2, COVID-19 Testing, Coronavirus Disease 2019, computed tomography, diagnosis, ground-glass opacity, Rare Diseases, Infectious Diseases, Vaccine Related, Clinical Research, Prevention, Pneumonia, Clinical Trials and Supportive Activities, Emerging Infectious Diseases, Biomedical Imaging, Biodefense, Detection, screening and diagnosis, 4.2 Evaluation of markers and technologies, Good Health and Well Being, Microbiology
Abstract

On 31 December 2019, a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, Hubei province, China, and caused the outbreak of the Coronavirus Disease 2019 (COVID-19). To date, computed tomography (CT) findings have been recommended as major evidence for the clinical diagnosis of COVID-19 in Hubei, China. This review focuses on the imaging characteristics and changes throughout the disease course in patients with COVID-19 in order to provide some help for clinicians. Typical CT findings included bilateral ground-glass opacity, pulmonary consolidation, and prominent distribution in the posterior and peripheral parts of the lungs. This review also provides a comparison between COVID-19 and other diseases that have similar CT findings. Since most patients with COVID-19 infection share typical imaging features, radiological examinations have an irreplaceable role in screening, diagnosis and monitoring treatment effects in clinical practice.

Published
2020

35. The safety and efficacy of myomectomy in the treatment of recurrent uterine fibroids after HIFU.

Author

Bao, Yi‐Ming, Ma, Wang‐Wa, Li, Shuang, Jiang, Li, Yang, Mei‐jie, and Chen, Jin‐Yun

Subjects
*UTERINE fibroids, *BLOOD transfusion, *UNIVERSITY hospitals, *MYOMECTOMY, *GORGES, *LAPAROSCOPIC surgery
Abstract

Objective: To evaluate the safety and efficacy of myomectomy for recurrent uterine fibroids (UFs) after high‐intensity focused ultrasound (HIFU) ablation. Methods: This was a retrospective study. Patients who underwent abdominal myomectomy (AM) and laparoscopic myomectomy (LM) from January 2018 to December 2021 at the Three Gorges Hospital of Chongqing University were included. Among them, 73 had undergone prior HIFU ablation (Group 1), while 120 had not undergone HIFU (Group 2). Outcome measures included operating time, estimated blood loss (EBL), blood transfusion, postoperative activity times (PAT), duration of hospital stay (DOHS), and complications. Results: The operating time was 90.0 min (70.5, 115.0) for Group 1 and 110.0 min (81.5, 130.0) for Group 2 (P < 0.05). During all AM pathways, there were no significant differences observed between the two groups in EBL, blood transfusion, PAT, DOHS, and complications; however, operating time was shorter in Group 1. The operating time, EBL, blood transfusion, PAT, DOHS, and complications were similar in both groups during LM pathway. During the follow‐up 40 (range: 24–53) months, the rate of relief, recurrence, and reintervention in Groups 1 and 2 was 78.1% versus 74.1%, 14.6% versus 16.4%, and 3.7% versus 2.6%, respectively (P > 0.05). Conclusion: Myomectomy is a safe and effective surgical method for treating recurrent UFs after HIFU. Myomectomy for treating recurrent UFs resulted in a shorter operative and hospital stay, reduced blood loss, faster postoperative recovery, and fewer complications, better symptom relief rates, and lower risk of recurrence or reintervention. These findings indicate that previous HIFU ablation does not worsen the outcomes of the subsequent myomectomy. Synopsis: Myomectomy is a safe and effective therapy in the treatment of recurrent uterine fibroids after HIFU. [ABSTRACT FROM AUTHOR]

Published
2024
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