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Early vs late cholecystectomy in mild gall stone pancreatitis: Anupdated meta-analysis and review of literature

World Journal of Clinical Cases 2021年第13期9卷 3038-3047页

作者： saqib Walayat Muhammad Baig Srinivas R Puli Department of Internal Medicine OSF Saint Francis Medical CenterUniversity of Illinois Peoria CampusPeoriaIL 61637United States Department of Gastroenterology University of IllinoisPeoriaIL 61637United States Department of Medicine University of Illinois-PeoriaPeoriaIL 61604United States

BACKGROUND Gallstone pancreatitis is one of the most common causes of acute *** remains the definitive treatment of choice to prevent *** rate of early cholecystectomies during index admission remains low due toperceived increased risk of *** compare outcomes including length of stay, duration of surgery, biliarycomplications, conversion to open cholecystectomy, intra-operative, and postoperativecomplications between patients who undergo cholecystectomy duringindex admission as compared to those who undergo cholecystectomy *** Method: Pooled proportions were calculated using both Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (randomeffects model).RESULTSInitial search identified 163 reference articles, of which 45 were selected andreviewed. Eighteen studies (n = 2651) that met the inclusion criteria were includedin this analysis. Median age of patients in the late group was 43.8 years while thatin the early group was 43.6. Pooled analysis showed late laparoscopiccholecystectomy group was associated with an increased length of stay by 88.96 h(95%CI: 86.31 to 91.62) as compared to early cholecystectomy group. Pooled riskdifference for biliary complications was higher by 10.76% (95%CI: 8.51 to 13.01) in the late cholecystectomy group as compared to the early cholecystectomy *** analysis showed no risk difference in intraoperative complications [riskdifference: 0.41%, (95%CI: -1.58 to 0.75)], postoperative complications [riskdifference: 0.60%, (95%CI: -2.21 to 1.00)], or conversion to open cholecystectomy[risk difference: 1.42%, (95%CI: -0.35 to 3.21)] between early and latecholecystectomy groups. Pooled analysis showed the duration of surgery to beprolonged by 39.11 min (95%CI: 37.44 to 40.77) in the late cholecystectomy groupas compared to the early *** patients with mild gallstone pancreatitis early cholecystectomy leads to shorterhospital

关键词： Cholecystectomy Gallstone pancreatitis Acute pancreatitis Laparoscopic cholecystectomy Biliary colic Open cholecystectomy

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Joint Design of QC-LDPC Codes for Coded Relay Cooperation

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Chinese Journal of Electronics 2016年第1期25卷 179-184页

作者： TANG Lei YANG Fengfan ZHANG Shunwai saqib Ejaz LUO Lin College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics School of Communication Engineering Nanjing Institute of Technology College of Information Science and Engineering Southeast University

This paper proposes an effective method to jointly design girth-4 cycle-free Quasi-cyclic(QC) Lowdensity parity-check(LDPC) codes for multi-relay cooperation in a Rayleigh fading channel, where the joint iterative decoding by Min-sum algorithm(MSA) based on the introduced joint Tanner graph is also presented at the destination. Theoretical analysis and simulation show that the proposed QC-LDPC coded cooperation outperforms the randomly coded cooperation under the same conditions.

关键词： Coded cooperation Low-density parity check(LDPC) codes Min-sum algorithm(MSA) Joint it erative decoding Treble-layer Tanner graph

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Optimization of gob ventilation boreholes design in longwall mining

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International Journal of Mining Science and Technology 2020年第6期30卷 811-817页

作者： saqib Ahmad Saki Jürgen F.Brune Muhammad Usman Khan University of Engineering and Technology Lahore Lahore 54890Pakistan Colorado School of Mines GoldenCO 80401USA

Gob ventilation boreholes(GVBs)are widely used for degasification in *** coal *** on geological conditions,30–50%of methane can be recovered from longwall gob using GVBs.A NIOSH funded research at the Colorado School of Mines confirmed that GVBs can efficiently reduce methane at the ***,GVBs can also draw some fresh air from the face and create explosive gas zones(EGZs).Explosive gas mixtures may be formed in gob areas due to the increased ingress of oxygen from *** is critical to identify the locations for GVBs for maximizing extraction of methane and minimizing hazards of *** study analyzes the effect of operating parameters and design of GVB on methane extraction,EGZs formation,and face and tailgate methane *** extraction,formation of EGZs,and concentration of methane in working areas are significantly impacted by various *** factors include the distance of work face and tailgate from GVBs,diameter of GVBs,vacuum pressure of wellhead,GVB distance from the roof of the coal seam,and number of operating GVBs in a *** fluid dynamics(CFD)evaluations suggest optimal design and operating parameters of GVBs that can contribute to maximum benefits with minimum risks.

关键词： Longwall mining Explosive gas zones Computational fluid dynamics Gob ventilation boreholes

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Trends in species distribution modelling in context of rare and endemic plants:a systematic review

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Ecological Processes 2022年第1期11卷 525-535页

作者： Ammad Waheed Qazi Zafeer saqib Muhammad Zaman‑ul‑Haq Department of Environmental Science International Islamic University IslamabadIslamabad 46000Pakista

Background:Many research papers have utilized Species Distribution Models to estimate a species’current and future geographic distribution and environmental *** study aims to(a)understand critical features of SDMs used to model endemic and rare species and(b)to identify possible constraints with the collected *** present systematic review examined how SDMs are used on endemic and rare plant species to identify optimal practices for future ***:The evaluated literature(79 articles)was published between January 2010 and December *** number of papers grew considerably over *** studies were primarily conducted in Asia(41%),Europe(24%),and Africa(2%).The bulk of the research evaluated(38%)focused on theoretical ecology,climate change impacts(19%),and conservation policy and planning(22%).Most of the papers were published in publications devoted to biodiversity conservation,ecological or multidisciplinary *** degree of uncertainty was not disclosed in most studies(81%).Conclusion:This systematic review provides a broad overview of the emerging trends and gaps in the SDMs *** majority of studies failed to present uncertainties and error ***,when model performance estimates are given,the model results will be highly effective,allowing for more assurance in the predictions they ***,based on our systematic review,we recommend that in the future rare and endemic SDMs should represent uncertainty levels and estimates of errors in the modelling process.

关键词： Species distribution modelling Endemic Rare Uncertainty measures Model validation

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Topological evolution of laminar juncture flows under different critical parameters

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Science China(Technological Sciences) 2014年第7期57卷 1342-1351页

作者： YOUNIS Muhammad Yamin ZHANG Hua HU Bo MEHMOOD saqib National Key Laboratory of Fluid Mechanics School of Aeronautical Science and Engineering Beihang University School of Astronautics Beihang University

Horseshoe vortex topological structure has been studied extensively in the past,traditional"saddle of separation"and new"attachment saddle point"topologies found in literature both have theoretical basis and experimental and computational evidences for *** laminar incompressible juncture flows at low Reynolds numbers especially are observed to have new *** concerning the existence of the new topology though found in literature,the topological evolution and its dependency on various critical flow parameters require further investigation.A Particle Image Velocimetry based analysis is carried out to observe the effect of aspect ratio,?*/D and shape of the obstacle on laminar horseshoe vortex topology for small *** in aspect ratio evolves the topology from the traditional to new for all the cases *** circular cross section obstacles are found more apt to having the new topology compared to square cross *** is noted that the sweeping effect of the fluid above the vortex system in which horseshoe vortex is immersed plays a critical role in this *** evolution is observed not only in the most upstream singular point region of horseshoe vortex system but also in the corner *** corner vortex topology evolves from the traditional type to new one before the topological evolution of the most upstream singular point,resulting in a new topological pattern of the laminar juncture flows"separation-attachment combination".The study may help extend the understanding of the three-dimensional boundary layer separation phenomenon.

关键词： horseshoe vortex saddle of attachment saddle of separation topological evolution sweeping effect

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A Levenberg–Marquardt Based Neural Network for Short-Term Load Forecasting

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Computers, Materials & Continua 2023年第4期75卷 1783-1800页

作者： saqib Ali Shazia Riaz Safoora Xiangyong Liu Guojun Wang School of Computer Science Guangzhou University Guangzhou510006Guangdong ProvinceChina Department of Computer Science University of AgricultureFaisalabad38000Pakistan Department of Computer Science Government College Women UniversityFaisalabad38000Pakistan

Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy *** ranges from an hour ahead prediction to a day ahead prediction. Variouselectric load forecasting methods have been used in literature for electricitygeneration planning to meet future load demand. A perfect balance regardinggeneration and utilization is still lacking to avoid extra generation and misusageof electric load. Therefore, this paper utilizes Levenberg–Marquardt(LM) based Artificial Neural Network (ANN) technique to forecast theshort-term electricity load for smart grids in a much better, more precise,and more accurate manner. For proper load forecasting, we take the mostcritical weather parameters along with historical load data in the form of timeseries grouped into seasons, i.e., winter and summer. Further, the presentedmodel deals with each season’s load data by splitting it into weekdays andweekends. The historical load data of three years have been used to forecastweek-ahead and day-ahead load demand after every thirty minutes makingload forecast for a very short period. The proposed model is optimized usingthe Levenberg-Marquardt backpropagation algorithm to achieve results withcomparable statistics. Mean Absolute Percent Error (MAPE), Root MeanSquared Error (RMSE), R2, and R are used to evaluate the model. Comparedwith other recent machine learning-based mechanisms, our model presentsthe best experimental results with MAPE and R2 scores of 1.3 and 0.99,respectively. The results prove that the proposed LM-based ANN modelperforms much better in accuracy and has the lowest error rates as comparedto existing work.

关键词： Short-term load forecasting artificial neural network power generation smart grid Levenberg-Marquardt technique

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Group-Based Handover Authentication Scheme for Machine-to-Machine Communication in LTE-A Network

Group-Based Handover Authentication Scheme for Machine-to-Ma...

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作者： Ali saqib 南京理工大学

学位级别：硕士

机器对机器通信因为其必要性和实时网络应用而被证明是LTE-A网络中的重要实体。机器对机器(M2M)或机器类型通信(MTC)也正在成为未来移动通信新技术时代的里程碑。通过实时网络应用,MTC在短时间内获得了极大的关注。MTC是设备之间通信的... 详细信息

机器对机器通信因为其必要性和实时网络应用而被证明是LTE-A网络中的重要实体。机器对机器(M2M)或机器类型通信(MTC)也正在成为未来移动通信新技术时代的里程碑。通过实时网络应用,MTC在短时间内获得了极大的关注。MTC是设备之间通信的平均源,其核心网络没有第三方的介入。随着MTC设备的快速增长和使用,安全漏洞的威胁也在增加,而安全是M2M通信中最重要的问题。当大量MTC设备一起请求注册到期望的网络时,单个设备必须通过网络完成其认证过程。同一时间大量设备的接入认证的过程可能遭受严重的信令拥塞,并且不愿意在LTE-A网络上为MTC设备提供鲁棒的安全机制。为了解决这些问题,我们提出了一种安全有效的基于群组的切换认证方案(SEGHAS),同时将其命名为改进的隐私感知切换认证(iPAHA)。它能够实现所有的安全机制,同时只需要较少通信和计算成本,能够快速切换,可以避免信令拥塞并防止LTE-A网络中M2M通信中的未授权用户接入。此外,通过使用Pro-Verif工具进行网络测试和针对恶意攻击的身份验证,最终,实验结果表明我们的方案在计算和信令开销方面是最合适的。

关键词：安全快速切换 M2M LTE-A 隐私性

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Implied volatility estimation of bitcoin options and the stylized facts of option pricing

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Financial Innovation 2021年第1期7卷 1508-1537页

作者： Noshaba Zulfiqar saqib Gulzar COMSATS University Islamabad-Wah Campus Wah CanttPakistan

The recently developed Bitcoin futures and options contracts in cryptocurrency derivatives exchanges mark the beginning of a new era in Bitcoin price risk *** need for these tools dates back to the market crash of 1987,when investors needed better ways to protect their portfolios through option *** tools provide greater flexibility to trade and hedge volatile swings in Bitcoin prices *** violation of constant volatility and the log-normality assumption of the Black–Scholes option pricing model led to the discovery of the volatility smile,smirk,or skew in options *** stylized facts;that is,the volatility smile and implied volatilities implied by the option prices,are well documented in the option literature for almost all financial *** are expected to be true for Bitcoin options as *** data sets for the study are based on short-dated Bitcoin options(14-day maturity)of two time periods traded on Deribit Bitcoin Futures and Options Exchange,a Netherlandsbased cryptocurrency derivative *** estimated results are compared with benchmark Black–Scholes implied volatility values for accuracy and efficiency *** study has two aims:(1)to provide insights into the volatility smile in Bitcoin options and(2)to estimate the implied volatility of Bitcoin options through numerical approximation techniques,specifically the Newton Raphson and Bisection *** experimental results show that Bitcoin options belong to the commodity class of assets based on the presence of a volatility forward skew in Bitcoin option ***,the Newton Raphson and Bisection methods are effective in estimating the implied volatility of Bitcoin ***,the Newton Raphson forecasting technique converges faster than does the Bisection method.

关键词： Bitcoin options Deribit Bitcoin smile Implied volatility estimation Numerical estimation

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Research on Real-Time Image Semantic Segmentation using Deep Learning

Research on Real-Time Image Semantic Segmentation using Deep...

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作者： saqib Mamoon 南京理工大学

学位级别：硕士

语义分割在图像的解释中起着重要的作用,对图像分析任务至关重要。语义分割是一样集分类、识别和定位于一体的任务。分类是指为每幅图像指定一个类别;检测是指对目标的定位和识别;而图像分割可以被视为像素级预测,因为它要将每个像素分... 详细信息

语义分割在图像的解释中起着重要的作用,对图像分析任务至关重要。语义分割是一样集分类、识别和定位于一体的任务。分类是指为每幅图像指定一个类别;检测是指对目标的定位和识别;而图像分割可以被视为像素级预测,因为它要将每个像素分类到其所属类别中。语义分割曾经也有很多基于图像处理和机器学习的方法,大部分都着眼于手工设计的技术来独立地识别每个像素点。在传统的方法中,随机森林和Boosting是最有效的策略。这些方法基于中心像素的类别概率进行预测。自深度神经网络重新出现以来,分割性能得到了显著的提高。尽管深度神经网络在语义分割任务中取得了巨大的成功,但是它的实时应用依然充满挑战。大量的特征通道、参数和浮点运算使得网络缓慢且计算量大,这对于机器人和自动驾驶等实时任务来说是不可取的。设计一个轻量级语义分割网络通常需要研究人员在性能和速度之间找到一个折衷点,由于神经网络的可解释性有限,这种折衷点通常是根据经验设定的。本文被研究并提出了一种使用深度神经网络的轻量级快速分割网络,称为阶段池化语义分割网络（Stage Pooling Semantic Segmentation Network,简称SPSSN）,该网络可以有效地重用低层或中间层多个阶段、不同空间分辨率的重要特征。本文网络主要包括三个部分:一个深层分支、一个浅层分支以及一个四阶段池化模块。深层分支提取特征并将分辨率下采样至原来的1/32。浅层分支在高分辨率上精化空间细节。阶段池化模块接收深层分支的输出,提取不同分辨率的特征,每个模块的输出都送入浅层分支。为了保证网络轻量,我们只简单地使用元素相加来融合各模块的特征。为了捕获图像中更多的上下文信息,深度分支后面接了空间金字塔池化。分割任务的图像分辨率至关重要,因此,SPSSN网络以全分辨率2048×1024的图像作为输入,仅使用1.42M参数,而无需预先训练即获得69.4%的m Io U,并且在Cityscapes数据集上的运行速度为每秒59帧。此外,SPSSN的分类准确率达到86.4%。由于它的轻量级架构,SPSSN能够直接在移动设备上实时运行。在Cam Vid上获得了64.3%的高结果,推理速度为105FPS。最后,为了证明所提出的网络的有效性,本文将其与最新的网络进行了比较。此外,我们还设计了流池化模块,该模块不仅接收深层分支的输出,还接收前面流池化模块的输出。与阶段池化模块不同的是,流池化中只有最后一个模块的输出被融入到浅层分支中。最后,为了展示提出网络的有效性,本文将与当前最新网络进行比较。

关键词：语义分割特征重用阶段池化流池化实时分割

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Painting Classification Using Machine Learning

Painting Classification Using Machine Learning

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作者： saqib Imran 西安理工大学

学位级别：硕士

本研究的重点是开发一个高效的软件系统,用于检索和分类博物馆及美术馆的美术图像。艺术藏品的数字化使人们对藏品的艺术风格快速分析和组织的需求越来越大。本论文所提出的算法包括两个阶段,旨在提高风格分类的精度。第一阶段,输入图... 详细信息

本研究的重点是开发一个高效的软件系统,用于检索和分类博物馆及美术馆的美术图像。艺术藏品的数字化使人们对藏品的艺术风格快速分析和组织的需求越来越大。本论文所提出的算法包括两个阶段,旨在提高风格分类的精度。第一阶段,输入图像被划分为五个子块。然后,使用深度卷积神经网络(CNN)对每个子块进行单独分类。第二阶段涉及利用浅层神经网络的决策模块。使用从第一阶段分类器获得的概率向量来训练该网络。在这个阶段中,将五个子块的结果逐个进行组合,以推导输入图像的最终风格分类。这种方法的创新点在于,第二阶段独立于第一阶段进行训练,使用概率向量而不是图像。这有助于补偿第一阶段中可能出现的错误,从而提高最终分类的准确性。为了评估所提出的方法,六个不同的预训练CNN模型,即AlexNet、VGG-16、VGG-19、GoogLeNet、ReSNet-50和Inceptionv3,用作第一阶段分类器。第二阶段分类器被实现为一个浅层神经网络。使用三个标准art数据集进行了实验试验,结果表明,所提出的方法在风格分类的准确性方面显著优于现有方法。总的来说,这项研究有助于开发有效的美术图像分析和分类软件系统,使公众更容所易通过数字平台访问这些图像。

关键词：美术风格分类绘画分类机器学习多阶段分类迁移学习数字人文

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