Three-Dimensional Simulations of RESET Operation in Phase-Change Random Access Memory with Blade-Type Like Phase Change Layer by Finite Element Modeling

An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current.

Three-dimensional Operation Design of Forest Engineering——A Case Study of Bagua Zhou in Nanjing City

[Objective] The aim was to construct a virtuous eco-system covering multi-populations, multi-layers and multi-products and to explore timber production of physical and non-physical products, in order to extend products operated in forestry engineering and seek a novel model for forestry engineering. [Method] A three-dimensional operation project was designed based on forestry lands in Bagua Zhou in Nanjing City. [Result] In the project, timber products, by-products in forest and relaxing products supplimented and supported each other, and a virtuous circle has been achieved. [Conclusion] The novel model makes simultaneous relaxing and working possible, which creat vaule together.

Preoperative diagnosis and operative effect of intracranial aneurysm with three-dimensional computed tomography angiography

BACKGROUND ： Digital subtraction angiography （DSA） is always regarded as the golden standard for diagnosis of intracranial aneurysm; however, the procedure is complex, traumatic, expensive and easy to induce vascular complication. Three-dimensional computed tomography angiography （3D-CTA） can make up deficiencies of DSA; therefore, it is used in clinical therapy wider and wider. OBJECTIVE ： To evaluate the clinical effect of 3D-CTA on disruption and hemorrhage of intracranial aneurysm pre- and post-operation and compare with the effect of DSA. DESIGN ： Auto-control contrast observation SETTING ： Department of Neurosurgery, Shengjing Hospital of China Medical University PARTICIPANTS ： A number of 106 patients with disruption and hemorrhage of intracranial aneurysm were selected from the Department of Neurosurgery, Shengjing Hospital of China Medical University from January 2003 to April 2006. All patients were diagnosed with cranial operation and consent. There were 47 males and 59 females aged from 3-76 years with the mean age of （47±13） years. Among them, 82 patients had extensive subarachnoid hemorrhage （SAH）, 7 had hemorrhage at longitudinal fissure, and 17 had hemorrhage at ambiens cistema and lateral fissure. Moreover, intraventricular hematocele was accompanied on 13 patients and hematom on 9 patients. METHODS： （1） 3D-CTA examination： Siemens SOMATOM Sensation 64 CT was used in this study. The thickness was 1 mm and interval of reconstruction was 0.8 mm. Localizing section was plainly scanned as the standard of canthus line. Scan ranged from 30 mm below sella to 50 mm above sella. Non-ion contrast medium of Omnipaque 350 （concentration of iodine was 350 g/L） was inserted into anterior vein of elbow with 18G trochar retained with high-pressured injectoc pum. The speed was 4.5 mL/s and the total volume was 80-100 mL with the means of 90 mL. Scan started at 10-20 s after injection of contrast medium. Original image was dealt with Leonardo workstation and retreated with Syngo software. Volume rendering and maximum intensity projection were used to reconstructed images, （2） All 106 patients suffered from occlusion of aneurysm clamp. Before operation, 3D-CTA was undertaken and DSA was followed. After operation, patients were rechecked with 3D-CTA. MAIN OUTCOME MEASURES： Comparisons between 3D-CTA and DSA. RESULTS ： All 106 patients were involved in the final analysis. （1） Examination of 3D-CTA and DSA： Among 118 patients with aneurysm, 110 were checked with 3D-CTA and the detected rate was 93.2% （110/118）. Among other 8 cases, 3 were negative and checked again with DSA; 1 had pericallosal aneurysm, 1 ophthalmic aneurysm, and 1 anterior choroidal artery of aneurysm. 3D-CTA results of other 5 cases were suspicious, and then, they were regarded as having aneurysm with DSA. Before operation, correlation among site, body, neck of aneurysm and peripheral anatomic structure were shown sufficiently. After operation, 82 patients were rechecked with 3D-CTA, which was complete occlusion, precise, unobvious constriction, emphraxis or remains as compared with 3D-CTA those pre-operation. （2） Characteristics of 3D-CTA： With multiple vessels and angles, 3D-CTA observed the relationship between aneurysm neck and carried artery and showed thrombosis in cavity of aneurysm, calcification of aneurysm wall and peripheral structure of vessel at the same time. However, DSA could not detect the reactions mentioned above. It could delete image of cranium, simulate image of operative route, eliminate artifact induced by metal, but not distinguish blood stream direction. Meanwhile, posterior communicating artery was always poor during circle of Willis artery showing. CONCLUSION： （1） 3D-CTA is characterized by simple operation and non-invasive showing vascular stereo structure and correlation. Therefore, it is significant for diagnosis and designing plan of operative approach and focal location pre-operation and evaluating effect post-operation. （2） 3D-CTA does not completely replace DSA on the diagnosis of intracranial aneurysm.

Numerical simulations and comparative analysis of two- and three-dimensional circulating fluidized bed reactors for CO2 capture

Carbon dioxide(CO2),the main gas emitted from fossil burning,is the primary contributor to global warming.Circulating fluidized bed reactor(CFBR)is proved as an energy-efficient method for post-combustion CO2 capture.The numerical simulation by computational fluid dynamics(CFD)is believed as a promising tool to study CO2 adsorption process in CFBR.Although three-dimensional(3D)simulations were proved to have better predicting performance with the experimental results,two-dimensional(2D)simulations have been widely reported for qualitative and quantitative studies on gas-solid behavior in CFBR for its higher computational efficiency recently.However,the discrepancies between 2D and 3D simulations have rarely been evaluated by detailed study.Considering that the differences between the 2D and 3D simulations will vary substantially with the changes of independent operating conditions,it is beneficial to lower computational costs to clarify the effects of dimensionality on the numerical CO2 adsorption runs under various operating conditions.In this work,the comparative analysis for CO2 adsorption in 2D and 3D simulations was conducted to enlighten the effects of dimensionality on the hydrodynamics and reaction behaviors,in which the separation rate,species distribution and hydrodynamic characteristics were comparatively studied for both model frames.With both accuracy and computational costs considered,the viable suggestions were provided in selecting appropriate model frame for the studies on optimization of operating conditions,which directly affect the capture and energy efficiencies of cyclic CO2 capture process in CFBR.

Autonomous process collaboration framework for C4ISR system interoperation

Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to fulfill a common mission are challenged by the ever-changing battlefield and hence requires a cross-organizational process management that produces an autonomous, flexible and adaptable architecture for collaborative process evolution. The traditional business process collaboration pattern is based on the predefined "public-view" perspective and cannot meet the requirement of the joint task operations. This paper proposes a flexible visibility control mechanism and a dynamic collaboration framework for modeling and generating collaborative processes. The mechanism allows collaborators to define a set of visibility rules to generate different views of the private processes for different collaborations, which gives a great flexibility for the collaboration initiator to decide on an appropriate collaboration pattern. The framework supports collaborators to dynamically and recursively add a new process or even a new organization to an existing collaboration. Moreover, a formal representation of the processes and a set of generation algorithms are provided to consolidate the proposed theory.

Balanced Functional Maps for Three-Dimensional Non-Rigid Shape Registration

Three-dimensional(3D)shape registration is a challenging problem,especially for shapes under non-rigid transformations.In this paper,a 3D non-rigid shape registration method is proposed,called balanced functional maps(BFM).The BFM algorithm generalizes the point-based correspondence to functions.By choosing the Laplace-Beltrami eigenfunctions as the function basis,the transformations between shapes can be represented by the functional map(FM)matrix.In addition,many constraints on shape registration,such as the feature descriptor,keypoint,and salient region correspondence,can be formulated linearly using the matrix.By bi-directionally searching for the nearest neighbors of points’indicator functions in the function space,the point-based correspondence can be derived from FMs.We conducted several experiments on the Topology and Orchestration Specification for Cloud Applications(TOSCA)dataset and the Shape Completion and Animation of People(SCAPE)dataset.Experimental results show that the proposed BFM algorithm is effective and has superior performance than the state-of-the-art methods on both datasets.

OPERATIONAL MODAL ANALYSIS SCHEMES USING CORRELATION TECHNIQUE

For some large-scale engineering structures in operating conditions, modal param- eters estimation must base itself on response-only data. This problem has received a considerable amount of attention in the past few years. It is well known that the cross-correlation function between the measured responses is a sum of complex exponential functions of the same form as the impulse response function of the original system. So this paper presents a time-domain operating modal identifcation global scheme and a frequency-domain scheme from output-only by cou- pling the cross-correlation function with conventional modal parameter estimation. The outlined techniques are applied to an airplane model to estimate modal parameters from response-only data.

深化职业教育产教融合的关键是实现跨界组织实体化运作

深化产教融合是职业教育实现高质量发展的核心举措。改革开放以来,我国职业教育产教融合在政策牵引和实践演绎的相互作用下,展现了由松散到紧密、由浅层次到深层次的演变历程。但长期以来,产教“融而不合”、校企“跨而不实”的现实困境始终难以破题。伴随市域产教联合体、行业产教融合共同体等新型产教跨界组织的产生与发展,以制度突破为基本前提,推进跨界组织的实体化运作成为深化职业教育产教融合的关键。而实现这一点,需要跨界组织具有符合实际的组织结构、发挥实效的主导权力、约束有力的职责分工、稳定的利益共享机制、有效的激励保障政策,也需要多方主体协同有效的共建共治。

广东省二、三级医疗机构延续护理部门设立及运作现况调查

目的:了解广东省二、三级医疗机构延续护理部门的设立及运作情况,为医疗机构建设延续护理部门、开展延续护理提供参考和借鉴。方法:采用便利抽样法于2023年5月4日—19日选取广东省110所二、三级医疗机构的护理管理人员进行调查,调查其所在医疗机构延续护理部门的建立情况、运作情况、阻滞因素及相关建议。结果:110所医疗机构中有35所(31.82%)设立了延续护理部门,58所(52.73%)拟计划开展延续护理服务,17所(15.45%)暂无设立延续护理部门及开展延续护理的计划。已开展延续护理的35所医疗机构中,2010年前设立延续护理部门的有3所(8.57%),2010—2018年有9所(25.71%),2019年至今有23所(65.71%)。35所医疗机构延续护理运作情况良好,但在医疗收费、医院-社区联动及延续护理质量指标设置方面需进一步加强和完善。51所(46.36%)医疗机构认为设立延续护理部门开展延续护理服务无障碍,59所(53.64%)认为存在障碍,障碍因素主要包括人力资源短缺(79.66%)、经济效益受限(76.27%)、实施场地缺乏(54.24%)、不知如何开展(32.20%)、院领导不支持(23.73%)等。结论:因缺乏统一、规范的标准及指南,广东省二、三级医疗机构延续护理部门的设立及运作情况参差不齐且存在多方面争议、困惑及不足。建议从“相关政策制度、部门组织架构、信息共享与协调机制、服务收费与支付机制、延续护理质量评价指标、工作人员绩效”等方面完善延续护理部门的设立及运作,从而推进延续护理的发展,助力实施健康中国战略。

异构平台要素协同理论方法研究

要素协同是协同作战发展的必经之路,杀伤链的动态重构是其典型特征.本文针对平台协同难以满足复杂作战任务需求的问题,提出了异构平台要素协同的解决思路和理论方法.首先分析了要素协同关系复杂性、协同能力不确定性两个难点问题;其次基于反馈机制的可重构架构对复杂作战网络进行建模,提出了杀伤链算子的要素动态重构、协同序参量的效能定量评估方法;最后基于仿真场景实现杀伤链的动态构建与重构,可指导要素协同的算法设计与工程实践.

跨线条件下城市轨道交通列车交路计划优化方法

跨线运营是城市轨道交通重点发展方向。针对跨线条件下列车交路计划编制问题,通过构造乘客出行时空网络图准确刻画复杂交路下的客流行为,建立以最小化列车走行公里与乘客出行时间成本为目标的混合整数规划模型。模型以列车交路方案、开行比例与频率为决策变量,并针对跨线交路与本线交路的行车冲突,考虑非等间隔发车,确定列车发车时刻。设计基于交路及开行频率搜索与运行间隔协调的定制分解算法。案例结果表明,列车跨线方向与乘客换乘主方向一致时,跨线交路可同时提升企业运营与乘客出行效益。换乘出行导致的断面客流量差异是跨线交路开行方案设置的主要依据。研究结论可为运营企业制定列车交路计划提供依据,有助于提高网络运输效率。

跨境电商自建独立站的优劣势分析

过去20多年,我国跨境电商行业经历了从无到有、从弱到强的发展历程。跨境电商行业在我国外贸领域具有举足轻重的地位,已成为推动外贸增长的重要引擎,其发展状况充分体现了我国对外贸易的创新与活力。当前,我国跨境电商产业正在加速外贸创新发展进程,通过优化产业结构、拓展市场空间、提升运营效率等方式,不断推动我国外贸行业的整体发展。但由于第三方平台运营成本增加、头部效应越来越明显,且常出现罚款或封号等运营问题,因此独立站逐渐成为跨境电商发展的新趋势。独立站服务商在本土化运营方面具有优势,能够更好地满足卖家的品牌需求,提高市场竞争力。独立站的建设和运营门槛逐渐降低,成为卖家向品牌化转型的重要手段。

区域轨道交通跨线站配线方案研究

“四网融合”发展背景下,区域轨道交通网络化运营成为重要发展趋势,而跨线站则是实现不同轨道交通线路互联互通的关键节点,因此有必要对跨线站设计进行探究。从优化车站运输组织出发,对跨线站配线方案进行研究,为实际配线布设提供参考。首先,以跨线运营模式为研究对象,根据跨线前后信号制式异同,将跨线分为同信号制式跨线和跨信号制式跨线,分析两种跨线模式列车作业种类及流程,并研究两种模式下行车组织、承载客流形式、应急管理等因素对于车站配线设置的相关需求。之后,结合配线需求,针对同信号制式和跨信号制式跨线站,分别提出了配线布置原则。最后,基于布置原则,在进一步分析两种跨线站列车作业特征基础上,研究并提出适用于不同车站构型、不同客流特征的典型配线设置方法,并进一步考虑运输组织适应性、建筑规模、工程量等因素提出适应不同实际运营场景的建议方案。通过研究,对于同信号制式跨线站,建议以在发车端设单渡线、交叉渡线等配线为主;对于跨信号制式跨线站,结合当前技术条件建议增设到发线,并根据实际需求设置折返线等其他配线。

非常规储层压裂支撑剂多级裂缝运移和沉降规律

水力压裂过程中支撑剂在裂缝中有效填充是形成高导流裂缝通道的关键。目前,关于支撑剂在裂缝中运移与沉降规律的研究方法多为物理实验或数值模拟,且主要聚焦支撑剂沉降结果,对支撑运移和沉降机理的研究较少。为进一步揭示支撑剂在裂缝中的运移和沉降规律,采用实验与数值模拟结合的方法探究了支撑剂尺寸、注入速度以及压裂液黏度对支撑剂在单一与交叉裂缝中的运移沉降行为的影响。研究结果表明:①支撑剂尺寸主要通过对沉降角的影响决定颗粒运移的分布,支撑剂尺寸越大,颗粒沉降角越大,运移距离越短;②注入速度对砂丘形态影响较大,当注入速度从0.2m/s增加至1.0m/s时,单一裂缝内砂丘有效支撑面积比和最大高度都明显降低,而分支缝内砂丘有效支撑面积比增加34.3%,表现出与单一裂缝中相反的变化趋势;③压裂液黏度主要影响流体携砂能力,随着压裂液黏度增加,主裂缝内砂丘有效支撑面积比降低8.4%,砂丘最大高度下降6.1cm,而在分支裂缝内表现为先增加后降低。结论认为,分支裂缝与主裂缝内支撑剂运移受施工因素影响往往表现出不同变化规律,该研究成果将进一步完善了水力压裂相关理论认识,同时为压裂现场施工设计优化提供了理论支撑。

超高压拱形爆破片中操作比对爆破压力作用机理仿真研究

十字开槽正拱形爆破片具有响应快、无碎片飞溅等优点,在使用过程中操作比(工作压力与爆破压力的比值)对爆破性能的影响值得研究。对十字开槽正拱形爆破片进行动态爆破试验,并建立有限元仿真模型,通过动态爆破试验结果验证有限元模型的可靠性;对不同操作比下的爆破片爆破性能进行研究,总结爆破压力变化规律,发现随着操作比的增大,爆破压力出现了减小,在部分情况下,与无操作比影响时的相对偏差大于10%,爆破压力的相对偏差随操作比的增加先增大后减小,转折点出现在操作比为30%~70%的范围内,且转折点对应的操作比随拱高的增加逐渐增大,爆破片的拱高增大,爆破压力的相对偏差整体变小,主要原因与残余应力和塑性形变有关。

基于数据驱动的跨境电商运营机制创新研究——以F品牌为例

跨境电商的猛速增长面临外部环境危机与内部治理结构不完整问题,迫使企业在数据驱动下实现运营从“野蛮生长”转向“精耕细作”。通过案例分析引入F品牌作为研究对象,分析基于不同运营机制阶段下的数据演化过程,剖析当下F品牌运营壁垒,遵循“数据—产品—数据”思维逻辑,构建数据库迭代技术模型,揭示以“数据价值发现—数据价值创造—数据价值实现”为研究范式的创新运营机制实现方式以提升运营者在合适的环境中做出及时反应,提高中国跨境电商企业的竞争力与影响力。

过街通道改造小净距临近运营地铁设计方案研究

随着城市化的快速发展,过街通道的改造与扩建成为了城市交通规划中不可或缺的一环。特别是当改造项目涉及临近运营地铁线路时,如何确保施工过程中的安全,同时减少对既有地铁线路运营的影响,成为了一个亟待解决的问题。本文基于小净距条件下过街通道改造的实际背景,利用三维有限元软件,分析过街通道改造基坑的“分块分层”设计方案,以及运营地铁隧道结构和轨道的变形规律,旨在为类似工程提供理论支持和实践指导。

城际铁路与高速地铁互联互通技术研究——以广州地铁22号线与广佛环城际铁路为例

目前,不同轨道交通制式间主要通过车站换乘的方式实现互联互通,随着珠三角地区城际及地铁线网的完善、经济的发展,旅客出行需求日益增长,对时效性和便捷性要求不断提升,为提高运输质量,有必要进一步研究实现不同轨道交通系统间跨线运营的互联互通。以广州地铁22号线(采用市域D型车)与广佛环城际铁路为例,从客流特征、运输需求、列车运输组织及工程技术方案等方面分析两者实现互联互通的可行性。研究结果表明:广佛环线与广州地铁22号线实现跨线运营在时效性上具有吸引力,具备客流支撑条件;城际线与采用D型车的高速地铁线在主要标准方面采取相关技术措施后可基本实现兼容统一,满足互联互通条件,但需要对信号、无线通信、票务等系统进行相关工程改造和兼容性设计。

考虑快慢车的城轨跨线运营开行方案与时刻表优化

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