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Makespan Minimization in Two-Machine Flow-Shop Scheduling under No-wait and Deterministic Unavailable Interval Constraints

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Journal of Systems Science and Systems Engineering 2020年第4期29卷 400-411页

作者： Kejia Chen debiao li Xiao Wang School of Economics and Management Fuzhou UniversityFuzhou 350116China

This paper systematically studies the two machine flow-shop scheduling problems with no-wait and deterministic unavailable interval *** minimize the makespan,three integer programming mathematical models are formulated for two-machine flow-shop with no-wait constraint,two-machine flow-shop with resumable unavailable interval constraint,and two-machine flow-shop with no-wait and non-resumable unavailable interval constraints problems,*** optimal conditions of solv-ing the two-machine flow-shop with no-wait constraint problem by the permutation schedules,the two-machine flow-shop with resumable unavailable interval constraint problem by the Johnson algorithm,and two-machine flow-shop with no-wait and non-resumable unavailable interval constraints problem by the Gilmore and Gomory Algorithm(GGA)are presented,*** the tight worst-case performance bounds of Johnson and GGA algorithms for these problems are also proved to be *** instances are generated to demonstrate the proposed *** on the experimental results,GGA obtains the optimal solution for the two-machine flow-shop with no-wait constraint *** it cannot reach the optimal solution for the two-machine flow-shop with resumable unavailable interval constraint problem,the optimal gap is 0.18%on average when the number of jobs is ***,under some special conditions,it yields the optimal solution for the two-machine flow-shop with no-wait and non-resumable unavailable interval constraints ***,GGA is an efficient heuristic to solve these problems.

关键词： Two-machine flow-shop no-wait unavailable interval Gilmore and Gomory Algorithm

Discrete particle simulation of mixed sand transport

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Particuology 2012年第2期10卷 221-228页

作者： Fengjiun Xiao lieiin Guo debiao li Yueshe Wang State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

An Eulerian/Lagrangian numerical simulation is performed on mixed sand transport. Volume averaged Navier-Stokes equations are solved to calculate gas motion, and particle motion is calculated using Newton＇s equation, involving a hard sphere model to describe particle-to-particle and particle-to-wall collisions. The influence of wall characteristics, size distribution of sand particles and boundary layer depth on vertical distribution of sand mass flux and particle mean horizontal velocity is analyzed, suggesting that all these three factors affect sand transport at different levels. In all cases, for small size groups, sand mass flux first increases with height and then decreases while for large size groups, it decreases exponen- tially with height and for middle size groups the behavior is in-between. The mean horizontal velocity for all size groups well fits experimental data, that is, increasing logarithmically with height in the middle height region. Wall characteristics greatly affects particle to wall collision and makes the fiat bed similar to a Gobi surface and the rough bed similar to a sandy surface. Particle size distribution largely affects the sand mass flux and the highest heights they can reach especially for larger particles.

关键词： Mixed sand transportHard sphere modelSand mass fluxParticle horizontal mean velocity

Sand particle lift-off velocity measurements and numerical simulation of mass flux distributions in a wind tunnel

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Journal of Arid Land 2017年第3期9卷 331-344页

作者： XIAO Fengjun DONG Zhibao GUO liejin WANG Yueshe li debiao National Demonstration Center for Experimental Geography Education College of Tourism and Environment Shaanxi Normal University Xi'an 710119 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China Xi'an Special Equipment Inspection Institute Xi'an 710065 China

lift-off velocity of saltating sand particles in wind-blown sand located at 1.0 mm above the sand bed surface was measured using a phase Doppler particle analyzer in a wind tunnel. The results show that the probability distribution of lift-off velocity can be expressed as a lognormal function, while that of lift-off angle follows an exponential function. The probability distribution of lift-off angle conditioned for each lift-off velocity also follows an exponential function, with a slope that becomes steeper with increasing lift-off velocity. This implies that the probability distribution of lift-off velocity is strongly dependent on the lift-off angle. However, these lift-off parameters are generally treated as an independent joint probability distribution in the literature. Numerical simulations were carried out to investigate the effects of conditional versus independent joint probability distributions on the vertical sand mass flux distribution. The simulation results derived from the conditional joint probability distribution agree much better with experimental data than those from the independent ones. Thus, it is better to describe the lift-off velocity of saltating sand particles using the conditional joint probability distribution. These results improve our understanding of saltation processes in wind-blown sand.

关键词： lift-off velocity lift-off angle joint probability distribution sand mass flux saltation

Deep learning in hepatocellular carcinoma:Current status and future perspectives

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World Journal of Hepatology 2021年第12期13卷 2039-2051页

作者： Joseph C Ahn Touseef Ahmad Qureshi Amit G Singal debiao li Ju-Dong Yang Gastroenterology and Hepatology Mayo ClinicRochesterMN 55904United States Biomedical Imaging Research Institute Cedars-Sinai Medical CenterLos AngelesCA 90048United States Internal Medicine University of Texas Southwestern Medical CenterDallasTX 75390United States Karsh Division of Gastroenterology and Hepatology Cedars-Sinai Medical CenterLos AngelesCA 90048United States

Hepatocellular carcinoma(HCC)is among the leading causes of cancer incidence and *** decades of research and development of new treatment options,the overall outcomes of patients with HCC continue to remain *** are areas of unmet need in risk prediction,early diagnosis,accurate prognostication,and individualized treatments for patients with *** years have seen an explosive growth in the application of artificial intelligence(AI)technology in medical research,with the field of HCC being no *** the various AI-based machine learning algorithms,deep learning algorithms are considered state-of-the-art techniques for handling and processing complex multimodal data ranging from routine clinical variables to high-resolution medical *** article will provide a comprehensive review of the recently published studies that have applied deep learning for risk prediction,diagnosis,prognostication,and treatment planning for patients with HCC.

关键词： Hepatocellular carcinoma Artificial intelligence Deep learning

Magnetic Resonance Imaging of Coronary Arteries:Latest Technical Innovations and Clinical Experiences

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Cardiovascular Innovations and Applications 2016年第B12期2卷 85-99页

作者： Yibin Xie Jianing Pang Qi Yang debiao li Biomedical Imaging Research Institute Cedars Sinai Medical CenterLos AngelesCAUSA Siemens Healthcare ChicagoILUSA Department of Bioengineering University of CaliforniaLos AngelesCAUSA

Cardiovascular disease(CVD)is the leading cause of death and a major health care challenge *** artery disease(CAD)is a primary underlying pathological process in the majority of cardiovascular disease *** resonance imaging(MRI)can play a potentially important role in the management of CAD as a noninvasive imaging modality without ionizing radiation,although its early promise has not been delivered because of several crucial technical ***,recent innovations in MRI have reopened the door,with tremendous opportunities for multiparametric assessment of CAD including luminal stenosis,plaque burden and composition,and disease activities such as infl ammation and *** MRI acquisition and reconstruction strategies now offer much increased spatial resolution and image quality and shortened examination times compared with conventional *** clinical experiences of coronary MRI indicated the potential to improve the current management of coronary atherosclerosis,such as identifying the patients at the highest risk and evaluating therapeutic *** this review we discuss the latest technical advances and clinical insights in coronary MRI.

关键词： magnetic resonance imaging magnetic resonance angiography coronary atherosclerosis coronary vessel wall imaging

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金属材料在超临界水中动态腐蚀特性

材料工程 2023年第11期51卷 61-70页

作者：刘云帆雷贤良苟灵通李德标西安交通大学动力工程多相流国家重点实验室西安710049 西安特种设备检验检测院西安710065

采用超临界流体静、动态腐蚀实验平台,对Q235,304,316L,P91,N80,3Cr13六种材料在超临界水拟临界区(22.5 MPa,375.6℃)和类气相区(22.5 MPa,407.6℃)环境下进行72 h的静态及动态腐蚀实验研究。结果表明:材料在超临界水环境中的动态腐蚀... 详细信息

采用超临界流体静、动态腐蚀实验平台,对Q235,304,316L,P91,N80,3Cr13六种材料在超临界水拟临界区(22.5 MPa,375.6℃)和类气相区(22.5 MPa,407.6℃)环境下进行72 h的静态及动态腐蚀实验研究。结果表明:材料在超临界水环境中的动态腐蚀速率明显高于静态腐蚀速率,流动加速腐蚀进程,其中304提升4倍以上;同时,随着材料耐腐蚀性的降低,动态条件对腐蚀增重的强化作用减弱。动态条件加剧腐蚀的因素为:流动剪切力加速超临界流体中的腐蚀性介质向基体表面移动,促进腐蚀化学反应的进行;流动剪切力对材料表面冲刷,促进材料表面Fe的溶解,加快腐蚀化学反应;剪切力的冲刷作用促进腐蚀产物晶体在壁面形成过程中的脱落,加速腐蚀进程。

关键词：超临界水金属材料动态腐蚀腐蚀机理

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3.0T MR自动呼吸导航对比增强全心冠状动脉磁共振血管成像的临床应用

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中国医学影像技术 2016年第4期32卷 504-508页

作者：贺毅戴沁怡安靖李德彪首都医科大学附属北京安贞医院医学影像科北京100029 美国洛杉矶雪松西奈山医院生物医学影像研究中心加利福尼亚州洛杉矶90001

目的评价3.0T MR自动呼吸导航全心冠状动脉磁共振血管成像（CMRA）诊断冠状动脉狭窄的临床应用价值。方法对50例临床疑诊或确诊冠心病或心肌病的患者行自动呼吸导航对比增强CMRA,其中33例经冠状动脉造影（CAG）证实。评价CMRA图像质量,... 详细信息

目的评价3.0T MR自动呼吸导航全心冠状动脉磁共振血管成像（CMRA）诊断冠状动脉狭窄的临床应用价值。方法对50例临床疑诊或确诊冠心病或心肌病的患者行自动呼吸导航对比增强CMRA,其中33例经冠状动脉造影（CAG）证实。评价CMRA图像质量,并与CAG相对照,评价CMRA诊断冠状动脉狭窄的效能。结果 1例CMRA图像质量较差,为1级;余49例CMRA图像质量均满足诊断要求,为2～4级。33例经CAG证实的患者共286段血管中,CRMA可显示238段（238/286,83.22%）,未显示48段（48/286,16.78%）。以患者数、血管支和血管段为单位,CMRA诊断冠状动脉狭窄的敏感度分别为80.95%（17/21）、79.31%（23/29）、84.62%（33/39）,特异度分别为75.00%（9/12）、91.09%（92/101）、75.00%（33/44）,阳性预测值（PPV）分别为85.00%（17/20）、71.88%（23/32）、75.00%（33/44）,阴性预测值（NPV）分别为69.23%（9/13）、93.88%（92/98）、96.91%（188/194）,准确率分别为78.79%（26/33）、88.46%（115/130）、92.86%（221/238）。结论 3.0T MR自动呼吸导航对比增强全心CMRA有助于诊断冠状动脉狭窄。

关键词：磁共振血管造影术冠状血管狭窄

FDTD方法在柱面波及半空间有耗介质散射问题中的应用

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西安电子科技大学学报 1998年第1期25卷 5-9页

作者：李清亮葛德彪石守元西安电子科技大学物理系

以柱面波及半空间有耗介质散射问题为例，研究了在时域有限差分计算分区的总场边界上入射波设置的波前逐步推进方法．给出了以Ｇｒｅｅｎ函数表述的、用于近－远场外推的统一公式，适用于自由空间以及地下介质电参数任意时的半空间中目... 详细信息

以柱面波及半空间有耗介质散射问题为例，研究了在时域有限差分计算分区的总场边界上入射波设置的波前逐步推进方法．给出了以Ｇｒｅｅｎ函数表述的、用于近－远场外推的统一公式，适用于自由空间以及地下介质电参数任意时的半空间中目标远区散射场的求解．几个数值计算例子验证了应用时域有限差分方法的有效性．

关键词： FDTD 电磁波电磁散射

胃癌患者血清中TNF-a IL-8的检测及临床意义

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长治医学院学报 2010年第6期24卷 404-406页

作者：李德彪长治医学院附属和平医院普外科 046000

目的:探讨血清TNF-a、IL-8水平与胃癌的关系。方法:选择胃癌住院患者64例,均经纤维内窥镜与病理检查确诊,用EliSA法测定胃癌患者术前、术后与健康者血清中TNF-a、IL-8含量,采用方差分析进行组间两两比较。结果:胃癌患者血清TNF-a、IL-8... 详细信息

目的:探讨血清TNF-a、IL-8水平与胃癌的关系。方法:选择胃癌住院患者64例,均经纤维内窥镜与病理检查确诊,用EliSA法测定胃癌患者术前、术后与健康者血清中TNF-a、IL-8含量,采用方差分析进行组间两两比较。结果:胃癌患者血清TNF-a、IL-8含量明显高于正常对照组(P<0.05),临床Ⅲ、Ⅳ期胃癌患者血清TNF-a和IL-8含量明显高于Ⅰ期、Ⅱ期(P<0.05),肿瘤根治术后血清TNF-a、IL-8含量较术前明显降低(P<0.05),但仍高于正常对照组(P<0.05)。结论:检测血清TNF-a、IL-8含量,对了解胃癌患者体内免疫状态,临床诊断和预后判断有重要意义。

关键词：胃癌 TNF-a IL-8