Effects of tide-surge interaction and wave set-up/set-down on surge: case studies of tropical cyclones landing China's Zhe-Min coast

Storm surge along the China＇s Zhe-Min coast is addressed using the tightly coupled surge model ofADCIRC＋SWAN. In this study, we primarily focus on the effects of surge-tide interaction and waveset-up/set-down. And the influences of intensity and landing moment of tropical cyclone （TC） arealso presented. The results show that： water elevation without considering tide-surge interactiontends to be underestimated/overestimated when TC lands during astronomical low/high tide;tide-surge coupling effect is more pronounced north of TC track （more than 0.7 m in our cases）;irrelevant to TC＇s intensity, wave set-up south of TC track is negligible because the depth-relatedwave breaking doesn＇t occur in water body blown towards open seas.

Numerical Simulation of Wave Height and Wave Set-Up in Nearshore Regions

Based on the time dependent mild slope equation including the effect of wave energy dissipation, an expression for the energy dissipation factor is derived in conjunction with the wave energy balance equation, and then a practical method for the simulation of wave height and wave set- up in nearshore regions is presented. The variation of the complex wave amplitude is numerically simulated by use of the parabolic mild slope equation including the effect of wave energy dissipation due to wave breaking. The components of wave radiation stress are calculated subsequently by new expressions for them according to the obtained complex wave amplitude, and then the depth-averaged equation is applied to the calculation of wave set-up due to wave breaking. Numerical results are in good agreement with experimental data, showing that the expression for the energy dissipation factor is reasonable and that the new method is effective for the simulation of wave set-up due to wave breaking in nearshore regions.

Wave Height Transformation and Set-up Between A Submerged Permeable Breakwater and A Seawall

In this study, we investigated wave transformation and wave set-up between a submerged permeable breakwater and a seawall. Modified time-dependent mild-slope equations, which involve parameters of the porous medium, were used to calculate the wave height transformation and the mean water level change around a submerged breakwater. The numerical solution is verified with experimental data. The simulated results show that modulations of the wave profile and wave set-up are clearly observed between the submerged breakwater and the seawall. In contrast to cases without a seawall, the node or pseudo-node of wave height evolution can be found between the submerged breakwater and the seawall. Higher wave set-up occurs if the nodal or pseudo-nodal point appears near the submerged breakwater. We also examined the influence of the porosity and friction factor of the submerged permeable breakwater on wave transformation and set-up.

Development of HSPECM set-up and its experiments

A new high frequency short pulse electrochemical machining(HSPECM) set-up was developed, including mechanical machine set-up, pulse power, drive system, interelectrode gap detection unit and controlling system. According to the present investigation, using a group of optimal parameters, an experiment replicating complex shape workpiece was made. From the photograph of the machined jobs, it can be seen that it has clear contour and smooth end surface. And the machining rate increases largely and the effective utilization of HSPECM in the micromachining field will be further strengthened.

Study on the Set-up and Set-down Induced by Breaking Waves Over A Reef

This paper proposes an equation to calculate breaking wave induced wave set-up and set-down along reef flat. The mathematical equation was derived based on the theory of radiation stress and the conservation of wave energy. The equation is primarily determined by several physical variables including the breaking wave index, the stable wave index, the attenuation coefficient of wave energy flux, and the flow velocity in the re-stabilization zone. A series of laboratory experiments were carried out to calibrate the theoretical equations. Specifically, the breaking wave index,the stable wave index, and the velocity over the reef flat were measured in the laboratory. The attenuation coefficient of wave energy flux in our theoretical equation was determined by calibration by comparing with the laboratory measured wave height. Furthermore, it has been put forward that the velocity based on cnoidal wave theory could be used to determine the velocity over the reef flat if there is no velocity measurement available. Overall, the proposed equation can provide satisfactory prediction of wave set-up and set-down along the reef flat.

Research on Unbounded Parallel-Batch Scheduling with Jobs Having Set-Up Times

We study the scheduling on an unbounded parallel-batch machine with jobs having set-up times to minimize a regular objective function which is either of the sumform or of the max-form.As we know,in the existing literature,the research about parallel-batch scheduling does not consider the set-up times of jobs.However,the set-up times of jobs are widely presented in practical applications.Each job considered in this paper has a set-up time.The set-up time of each batch is equal to the maximum set-up time of all jobs contained in the batch,and the processing time of each batch is equal to the longest processing time of the jobs contained in the batch.Depending on the different definitions of the completion time of a job,we consider two types of jobs:batch jobs and drop-line jobs.For batch jobs,the completion time of a job is given by the completion time of the batch containing this job.For drop-line jobs,the completion time of a job is given by the starting time of the batch containing this job plus the processing time of this job.In this paper,we give pseudo-polynomial time algorithms for the above scheduling problems in which the jobs have agreeable processing times and set-up times.In addition,when the objective functions are the total weighted completion time,the maximum lateness,and the maximum cost,we present a polynomial time algorithm,respectively.

An Evaluation of Inter-Fractional Set-Up Errors in Patients Treated with Distinct Immobilization Equipment for Varying Anatomical Regions

This study aims to evaluate inter-fractional set-up errors in patients treated with distinct immobilization equipment (thermoplastic mask, knee-fix and feet-fix, wing board and vac-lok) for four anatomical regions including brain, head and neck (HN), thorax and pelvis. Data of randomly selected 140 patients who were treated for four anatomical regions were obtained using Hi-Art Helical Tomotherapy (HT) system. Pre-treatment planning was based on automatic registration readings of computed tomography (CT) and mega-voltage computed tomography (MVCT) on a daily basis. Distinct immobilization equipment was used for varying anatomical regions. Individual mean set-up error (M), systematic error (Σ), and random error (σ) values were calculated through daily translational and rotational deviation values. The size of translational, systematic and random error was 1.31 - 4.93 mm for brain, 2.28 - 4.88 mm for HN, 4.04 - 9.90 mm for thorax, and 6.34 - 14.68 mm for pelvis. Rotational values were as follows: 0.06&deg - 0.73&deg for brain, 0.42&deg - 0.6&deg for HN, 0.48&deg - 1.14&deg for thorax and 0.65&deg - 1.05&deg for pelvis. The highest translational, systematic and random error value was obtained from the pelvic regional. The highest standard and random error value in pitch and roll was produced in the rotational direction of the pelvis (0.05° and 0.71°), while the highest error value in yaw was (1.14°) produced from thorax. Inter-fractional set-up errors were most commonly produced in the pelvis, followed by thorax. Our study results suggest that the highest systematic and random errors are found for thorax and pelvis. Distinct immobilization equipment was important in these results. Safety margins around the clinical target volume (CTV) are changeable for different anatomical regions. A future work could be developed to new equipment for immobilization because of the reduced margins CTV.

An Experimental Set-Up for the in Vitro Simulation of a Physiological Pulsatile Flow in the Abdominal Aorta

In vitro experimental set-up is an important tool for investigating abdominal aortic aneurysm (AAA). Accurate reproduction of the physiological pulsatile flow waveform in the abdominal aorta at various anatomic locations is an important component of these experimental methods. The objective of this study is to establish an experimental set-up to generate a physiological pulsatile flow for in vitro simulations of the abdominal aorta. The physiological flow was established by a computer-controlled peristaltic pump and the flow field in a circular straight pipe is measured under pulsatile flow conditions by a 2-dimensional particle image velocimetry system (2D-PIV). Experimental results show that the in vitro experimental set-up provides a flow with a period of 2 s, a reasonable cross-sectional velocity distribution and an approximate inlet velocity profile that is close to the human abdominal aorta.

Target for Power Construction in 9th Five-year Plan Period Set-up

According to the National Meeting on Power Construction and Cost Control held in Beijing on 26th August 1996, the target for power construction in the period of 9th Five- year Plan is set-up as follows:

Design of Fin-propeller Test Set-up and Analysis of Roll Stabilization Ability

Presents the fin-propeller test set-up to solve the problem of roll stabilization with ships in full speed range, withwhich, tests were run in water rank for acquisition of data, and concludes from data acquired that the fin-propeller test set-up produces more lift than simple fin, and provides lateral thrust as well, and it is therefore an effective roll stabilization devicefor ships in full speed range.

基于启动时间和完全故障的双阶段休假排队系统的流体模型性能分析

基于风力发电路灯的能量转化机制,该文构建并分析了具有启动时间和完全故障策略的M/M/1排队系统驱动的流体模型.首先,对驱动系统进行模型描述,运用矩阵几何解方法得到驱动系统的稳态概率分布.其次,引入流体模型的净输入率结构,并利用概率分析方法得到流体库存水平在稳态条件下的微分差分方程组,进而运用Laplace-Stieltjes transform(LST)方法得到稳态条件下库存量的均值及空库概率.根据性能指标构建系统的费用函数,在数值分析中给出系统参数对性能指标和费用的影响.

胸部肿瘤三维适形调强放疗摆位误差相关因素分析

分析胸部肿瘤患者行三维适形调强放疗(IMRT)时产生摆位误差的相关因素,以准确计算出临床靶区(CTV)外放边界(摆位扩边(SM)值),从而实现安全放疗.以莆田学院附属医院接受IMRT治疗的83例胸部恶性肿瘤患者为研究对象,应用体位固定技术及电子射野影像装置(EPID)测量比较胸部恶性肿瘤IMRT的摆位误差,采用多元线性回归分析方法对摆位误差相关因素进行分析,进而分类计算出其SM值.结果显示,83例受试者在X轴、Y轴、Z轴上的SM值分别为0.31、0.28、0.28 cm;靶区定位、性别及肺容量分别为Y轴个体随机误差、Z轴个体系统误差、Z轴个体随机误差的独立影响因素.这表明肿瘤患者行IMRT治疗时靶区定位、性别及肺容量在不同方向上影响其摆位误差.

外阴癌膀胱截石位电子线放疗支架在体位固定中的临床价值分析

目的探讨外阴癌膀胱截石位电子线放疗支架在体位固定中的临床价值。方法选取32例外阴癌患者,随机分为两组,各16例。两组均行膀胱截石位电子线放疗,对照组采用传统放疗摆位,研究组采用放疗支架进行摆位。比较两组摆位误差、照射野中心偏移距离、计划靶区(PTV)剂量学指标[适形指数(CI)、均匀性指数(HI)]、放疗疗效、摆位舒适度。结果研究组X轴、Y轴、Z轴摆位误差均小于对照组(P<0.05);研究组照射野中心偏移距离小于对照组(P<0.05);研究组CI、HI与对照组比较,均有显著性差异(P<0.05);研究组缓解率(87.50%)与对照组(81.25%)比较,差异无统计学意义(P>0.05);研究组摆位舒适度(93.75%)高于对照组(56.25%)(P<0.05)。结论外阴癌膀胱截石位电子线放疗支架能有效提高摆位准确度和患者舒适度,同时能降低照射野中心偏移距离,提高放疗照射剂量精准性,具有推广应用价值。

组织因素对用户创业企业绩效的影响机制研究——基于模糊集定性比较分析

用户成为创业者,为“大众创业、万众创新”带来新的活力,用户创业及其绩效问题已成为创业领域研究的重点之一。以65个用户创业企业为样本,基于用户创业企业组织因素的创业能力、创业氛围、创业拼凑、创业导向和创业战略5个前因条件,构建用户创业企业绩效影响机制模型。运用模糊集定性比较分析(fsQCA)方法,探究5个条件变量组合形成的不同组态对用户创业企业绩效的影响。研究结果表明:创业拼凑是产生高用户创业企业绩效的必要条件;高用户创业企业绩效的路径可被归纳为团队资源内外驱动型和策略资源双向驱动型,其与构成非高用户创业企业绩效的组态呈现非对称性关系。建议用户创业企业有意识地培养创业拼凑能力,发挥多种因素的协同效应,进而促进企业绩效提升。

基于光学表面监视系统的乳腺癌放射治疗定位质控

目的将光学表面监视系统(OSMS)用于乳腺癌的放射治疗(简称放疗)定位环节的质量控制,探索其可行性和有效性。方法选择海南省肿瘤医院2017年9月至2020年3月女性乳腺癌患者60例,年龄27~71岁,平均年龄46.1岁(标准差9.91岁);手术治疗方式,保乳术后放疗26例,乳腺全切术后放疗34例;肿瘤部位,左乳43例,右乳17例。根据是否行OSMS质控,分为试验组29例(定位过程中加入OSMS质控)和对照组31例(未加入OSMS质控)。试验组定位完成后,增加OSMS重复性监测环节,通过OSMS测量患者重复摆位的平移误差和旋转误差,并依据测量结果对固定装置进行调整;对照组不加入OSMS辅助,按照科室定位流程,常规定位。在后续的放射治疗过程中,采集摆位影像,记录两组患者的位置偏差数据。分析两组的摆位偏差。结果试验组摆位偏差总体偏小。在Z方式(腹背方向)及总偏差上差异有显著统计学意义[(0.056±0.286)cm vs(0.192±0.406)cm、(0.474±0.237)cm vs(0.661±0.299)cm。P<0.01]。试验组系统误差和随机误差均偏小,在X方向(左右方向)和Z方向上差异有统计学意义(P<0.05),且计算得到的计划靶区(PTV)外放边界也更小。试验组摆位误差在X、Y、Z方向上分布区间更加集中在小误差(≤0.3 cm)范围,差异有显著统计学意义(P<0.01)。结论基于OSMS的乳腺癌放疗定位安全有效,可以识别出重复性差的治疗体位和标记点,帮助提高放疗定位质量。

摆位误差对乳腺癌术后放疗患者心脏剂量影响

目的研究模拟摆位误差对左侧乳腺癌患者术后放疗心脏受照剂量的影响。方法选取17例左侧乳腺癌根治术后进行调强放疗的患者为研究对象。在计划系统中,模拟靶区中心相对于计划射野中心的偏移,包括向颅(S)、尾(I)、左(L)、右(R)、前(A)和后(P)各移动5 mm,并评估心脏受照剂量,分析不同方向的摆位误差对心脏剂量的影响。结果原始计划心脏平均剂量(Dmean)为5.72 Gy。射野中心向6个不同方向移动5 mm后,L、A、S方向心脏受照剂量减少,R、P、I方向心脏受照剂量增加,P方向心脏Dmean增加(1.46±0.24)Gy,R方向心脏Dmean增加(1.14±0.17)Gy,I方向心脏Dmean增加(0.43±0.25)Gy。结论左侧乳腺癌改良根治术后放疗,向R、P、I方向的摆位误差可增加心脏受照剂量,向L、A、S方向的摆位误差可减少心脏受照剂量。

自主最大笑容三维面像与数字化三维牙列模型整合方法的建立及其准确性研究

目的拟建立一种将自主最大笑容(AMS)三维面像与数字化三维牙列模型整合的方法,以实现在三维面像背景下显示数字化正畸终末位设计的目的。方法利用Geomagic Studio软件,通过手动注册和全局注册功能,将AMS三维面像和初始牙列模型进行配准对齐,然后用终末位牙列模型在原位替换初始牙列模型,并去除AMS三维面像口内区域,从而实现AMS三维面像和终末位牙列模型的融合显示。计算AMS三维面像和初始牙列模型上4组对应标志点对间的距离,通过配对t检验评估配准操作的准确性。结果该方法成功实现了AMS三维面像与初始、终末三维牙列模型的整合。两次配准对齐后,点对间的平均距离分别为(1.19±0.55)mm和(1.55±0.59)mm。两次测量结果的差异无统计学意义(P>0.05),且具有很高的一致性(组内相关性系数=0.914)。结论本研究建立了AMS三维面像与数字化初始、终末三维牙列模型整合的方法。该方法具有较高的准确性,有助于实现在三维面像背景下数字化正畸终末位设计效果的显示,从而提升以隐形正畸为代表的数字化正畸终末位设计的质量。

负压真空袋固定全上肢在乳腺癌保乳术后调强放疗中体位精度及重复性研究

目的 探讨负压真空袋固定全上肢在乳腺癌保乳术后调强放射治疗(IMRT)中的体位精度及重复性价值。方法 回顾性分析2020年10月至2022年5月乳腺癌保乳术后调强放疗患者34例,随机均分为试验组和对照组。试验组采用80 cm×120 cm真空袋全上肢塑型固定;对照组采用70 cm×100 cm真空袋上肢部分塑型固定,双手交叉置于额前。治疗前后分别获取左右(X)、头脚(Y)、腹背(Z)三维方向分次间、分次内的摆位误差(ΔP1、ΔP2);由ΔP1计算临床靶体积(CTV)至计划靶体积(PTV)三维方向的外放范围。计算当次治疗前后三维方向体表线偏移值ΔP3。两组ΔP1、ΔP2、ΔP3在同一方向上的摆位误差采用配对样本t检验;ΔP1与ΔP3在组内的相关性采用Pearson相关性分析。结果 试验组和对照组在X、Y、Z三维方向上的ΔP1进行比较,差异无统计学意义(P>0.05);试验组和对照组在X、Y、Z三维方向上的PTV外扩值分别为4.97 mm、6.31 mm、5.38 mm和8.24 mm、9.96 mm、7.52 mm,差异有统计学意义(P=0.02)。试验组和对照组在Z方向的ΔP2分别为(0.29±1.02)mm、(-0.09±1.49)mm,ΔP3分别为(-0.63±0.95)mm、(-1.05±1.35)mm,两组差异均有统计学意义(P<0.05)。Pearson相关性分析结果显示,两组ΔP1与ΔP3在Z方向均存在相关性(r=0.450,P<0.05;r=0.630,P<0.05)。结论 真空袋固定全上肢可提高乳腺癌保乳术后全乳IMRT中的体位精度及重复性,可能有一定的临床参考及推广价值。

基于中心城市偏向的城市功能与产业发展失衡问题研究——以长江经济带为例

本文在利用熵值法测算2008—2019年长江经济带96个城市市场型功能、非市场型功能和产业发展的基础上,构建城市功能与产业发展失衡度指标,实证分析中心城市偏向对城市功能与产业发展失衡的影响。研究结果发现,市场偏向降低城市功能与产业发展失衡度,政府偏向则加剧二者的失衡度;中心城市偏向通过城市开发和公共服务建设影响城市功能与产业发展失衡度;不同区域、不同市场化程度和不同规模城市间中心城市偏向影响城市功能与产业发展的失衡度存在明显差异性。通过将撤县设区的准自然实验作为中心城市偏向的外生冲击检验,发现撤县设区强化了城市功能与产业发展失衡度,为深入理解中心城市偏向的影响提供经验证据。