Numerical Investigation on the Deformation of the Free Interface During Water Entry and Exit of a Circular Cylinder by Using the Immersed Boundary-Multiphase Lattice Boltzmann Flux Solver

In this work,the deformation of free interface during water entry and exit of a circular cylinder is investigated numerically by using the two-dimensional(2D)immersed boundary-multiphase lattice Boltzmann flux solver(IB-MLBFS).The fluid domain is discretized by finite volume discretization,and the flux on the grid interface is evaluated by lattice Boltzmann equations.Both the implicit velocity correction and the surface flux correction are implemented by using the immersed boundary-method to consider the fluid-structure interaction and the contact interface between the multiphase fluids and the structure.First,the water entry of a circular cylinder is simulated and the results are compared with the experiment,which considered the length-diameter ratio of the circular cylinder.The reliability of 2D simulation is verified and the deformation of the free interface is well investigated.Afterward,the water exit of a circular cylinder with constant velocity is simulated,which is less researched.In addition,the results show the advantage of present IB-MLBFS to some extent.Finally,the water exit and re-entry of a circular cylinder are presented,and the results present the complex deformation of the free interface and the dynamic response of the moving structure.Based on the numerical results,the free interface of the multiphase fluids is well captured,and the contact interface on the boundary of the moving structure is accurately presented by the IB-MLBFS.

Connectivity Analysis of Vehicles in Highway with One Entry/Exit and One RSU

In this paper, we consider a unidirectional highway road with one entry/exit uniformly distributed on the road interval. One road side unit (RSU) is located on the position of the entry/exit. We build an analytical model to study the network connectivity problem. In building the analytical model, we take into account several parameters, such as vehicle arrival rate, vehicle moving speed, vehicle communication radius, RSU communication radius, highway road length and the probability of vehicles driving through the entry/exit. The analytical model is verified by using simulation tools.

A Study of How Market Entry and Exit Matter for Productivity in China＇s 426 Industries

Based on extensive micro data sets, this paper examines the relationship among large-scale entry and exit, competition and total factor productivity （TFP） growth of China＇s industry during economic transition and market opening. We have arrived at these findings： market opening spurs entry and exit of large numbers of non-state-owned enterprises （non-SOEs） and facilitates dynamic competition; through the stimulation effect of competition, entry and exit push TFP growth on the part of enterprises; through the resource reallocation effect, entry and exit promote growth of the aggregate TFP. However, results indicate that the resource allocation efficiency remains very low in capital-intensive industries where the government intervenes a lot. To conclude, promoting open competition is significant to the growth of industrial sectors ＇productivity.

Application of Connected Truck Data to Evaluate Spatiotemporal Impact of Rest Area Closures on Ramp Parking

Ensuring adequate access to truck parking is critical to the safe and efficient movement of freight traffic. There are strict federal guidelines for commercial truck driver rest periods. Rest areas and private truck stops are the only places for the trucks to stop legally and safely. In locations without sufficient parking areas, trucks often park on interstate ramps, which create safety risks for other interstate motorists. Historically, agencies have employed costly and time intensive manual counting methods, camera surveillance, and driver surveys to assess truck parking. Connected truck data, available in near real-time, offers an efficient alternative to practitioners to assess truck parking patterns and identify areas where there may be insufficient safe parking spaces. This paper presents a case study of interstate I-70 in east central Indiana and documents the observed spatiotemporal impacts of a rest area closure on truck parking on nearby interstate ramps. Results showed that there was a 28% increase in parking on ramps during the rest area closure. Analysis also found that ramps closest to the rest area were most impacted by the closure, seeing a rise in truck parking sessions as high as 2.7 times. Parking duration on the ramps during rest area closure also increased drastically. Although it was expected that this would result in increased parking by trucks on adjacent ramps, this before, during, after scenario provided an ideal scenario to evaluate the robustness of these techniques to assess changing parking characteristics of long-haul commercial trucks. The data analytics and visualization tools presented in this study are scalable nationwide and will aid stakeholders in informed data-driven decision making when allocating resources towards improving the nations commercial vehicle parking infrastructure.

基于EXIT图的连续变量密钥分发数据协调优化

在量子密码通信中,未优化的低密度奇偶校验（LDPC）码的度分布性能较差,得到的协调效率较低,且传输距离较短。针对上述问题,提出一种基于连续变量的量子密钥分发数据协调算法。利用外信息转移图分析特点,从基于粒子群的高斯近似算法得到的度分布中,通过比较门限值大小筛选出性能更好的度分布,进而优化低密度奇偶校验码。仿真结果表明,与密度进化算法和高斯近似算法相比,外信息转移图可以有效地优化LDPC码度分布,同时,当连续变量分组数为2×105时,与未优化的LDPC码相比,优化的LDPC码能降低收敛信噪比,提高协调效率,延长传输距离。

Wikidata中数据来源分析

文章选取人名名称作为研究对象,分析了Wikidata中人物条目的属性及来源的描述能力,并使用数据质量维度评估了来源质量。研究发现:Wikidata使用多个属性对人物条目进行描述,Wikidata人物类来源可靠性不高,Wikidata数据来源本身的质量难以保证。

Medication Regularities of Traditional Chinese Medicine for treating COVID-19: A data mining-based literature analysis

Objective:Traditional Chinese Medicine(TCM)has been widely used as an approach worldwide.To explore distribution regularities of the nature,flavor,and meridian entry of Chinese Medicines(CMs)for treating Corona Virus Disease 2019(COVID-19)by data mining in the relevant literature to provide basis for clinical prescriptions.Methods:The database was established by collecting and analyzing the prescriptions for COVID-19 in regional schemes of CMs for COVID-19 announced by National health Commission and Administration of TCM of the provinces,municipalities and autonomous regions.The frequencies and the distribution regularities of the nature and flavor of these Chinese medicines were statistically analyzed by SPSS 21.0.Results:CMs with bitter,xin,sweet flavors were widely used in treating COVID-19,most of them entered lung,stomach,spleen,and heart meridian entries,with warm,cold,flat properties.Warm property CMs were used most in coastal areas such as Liaoning,Hebei,Tianjin,Shandong,Jiangsu,Shanghai,Zhejiang,Guangxi and inland areas such as Ningxia,Shanxi,Hubei,and Sichuan,and Guizhou,while cold property CMs were used most in coastal areas such as Heilongjiang,Jilin,Fujian,Guangdong,Hainan and inland areas such as Inner Mongolia,Xinjiang,Beijing,Shanxi,Jiangxi,and Hunan.Conclusion:The medication regularities of nature and flavor of CMs might reflect the pathogenesis of COVID-19.CMs were used variously according ro the region,reflected the dialectical characteristics of TCM,patients were treated in accordance with seasonal conditions,local conditions and the patient's individuality.

职业教育“双师型”教师资格认定的“结”与“解”

“双师型”教师是推进职业教育高质量发展的第一资源,是加速实现职业教育现代化的重要力量。我国职业教育“双师型”教师经过了概念内涵逐步清晰、教师数量逐年增多、资格认定标准逐渐完善、相关法律制度体系日趋严密的发展历程。“双师型”教师资格的取得与丧失,事关教师切身利益,关乎职业教育师资队伍整体素质与建设水平。建立完备的职业教育“双师型”教师资格准入退出机制,将为建设一支符合中国实际、体现职教特色的“双师型”教师队伍,提供充足的制度支持和法律保障。为此,需要分层分类细化标准要求,建立健全认证与评价机制,强化彰显职业教育跨界属性,补强优化法律制度保障。

骗取出入境证件行为的刑法定性

对于以提供伪假证明材料等方式骗取出入境证件行为的刑法定性,存在行政法中的出境入境证件与刑法中的出入境证件混同、对出售出入境证件罪中出售行为的认定争议较大等诸多问题。《出境入境管理法》规定的外国人停留居留证件既不属于司法解释例示的出入境证件,也不可归为司法解释所规定的“其他出入境时需要查验的资料”,故不属于刑法意义上的“出入境证件”。对于骗得出入境证件后将该证件出售的行为,应当将其认定为出售出入境证件罪;对于有偿为他人骗取出境证件的行为,可以将其认定为骗取出境证件罪或骗取出境证件的行政违法行为;对于有偿为他人骗取入境证件的行为,只能认定为骗取入境证件的行政违法行为。骗取入境证件行为与骗取出境证件行为的规制必要性相当,应在刑事立法层面将“骗取出境证件罪”调整为“骗取出入境证件罪”,从而进一步完善对出入境证件的刑法保护。

数字普惠金融的区域经济韧性效应及机制——基于中小微经营主体进入退出视角

中小微市场经营主体对冲击更为敏感且受金融约束更为突出,数字普惠金融发展有助于中小微经营主体获得金融支持应对各种冲击,进而增强区域经济韧性。本文以2011—2021年288个地级市面板数据为样本,基于中小微经营主体进入退出视角,应用中介效应模型检验了数字普惠金融对区域经济韧性的影响效应及其作用机制。研究发现:数字普惠金融显著促进了区域经济韧性提升,这一结论在内生性处理和稳健性检验后仍然成立。异质性分析表明,数字普惠金融对区域经济韧性的促进效应在东部地区更显著。相对于大城市而言,中小城市数字普惠金融发展的区域经济韧性效应更强。机制分析显示,数字普惠金融通过强化中小微经营主体进入退出机制提升区域经济韧性。为了更好地发挥数字普惠金融的区域经济韧性效应,应完善数字普惠金融设施建设、创新数字普惠金融产品和加强数字普惠金融培训。

基于MySQL数据库的数据录入系统设计研究

为进一步提升数据处理的自动化水平,基于MySQL数据库,设计并实现了一个数据录入系统。首先,明确了系统流程与总体架构,详细设计了数据库结构,并对系统功能模块进行划分,尤其在核心技术方面,重点设计了MySQL数据库与Allegro软件之间的通信协议,开发了关键的通信接口。其次,对主要功能进行实现。该系统采用SKILL语言与IPC通信原理,实现了数据的自动采集、高效录入、安全保存,以及网页端展示与处理等功能。

基层涉外警务工作的困境与破解——以湖北省W市为观察视角

基层涉外警务工作具有维护国家安全、保障社会稳定、促进国际交流、推进经济社会发展等重要作用,但当前我国基层涉外警务工作面临管理服务理念存在偏差、管理服务整体力量薄弱、管理服务制度有待完善、管理服务机制不够健全、管理服务技术手段不足等困境。涉外警务工作的复杂性和敏感性要求公安机关更加注重合法合规执法。基层涉外警务工作应以问题为导向,从转变管理服务立法理念、完善地方管理服务制度、深化管理服务机制改革、创新管理服务方式举措、建强管理服务专业队伍等方面予以改革。

我国科学数据出境管理对策研究

信息化时代,科技创新越来越依赖于科学数据。随着国际竞争形势愈发严峻,科学数据安全与出境管理问题日益凸显。当前,我国科学数据出境管理存在政策法规不完善、技术能力不够、国际合作机制不完备等问题,亟须完善相关管理制度,建立协调统一的科学数据出境管理体系;加强数据安全监测与监管技术研发,推动科学数据关键技术创新升级;积极探索双边多边国际科学数据合作,引领国际科学数据规则框架制定。与其他国家一起共同应对科学数据出境中的风险挑战,推动全球科学数据安全、有序流通,加速科技创新发展。

高校“强基计划”动态进出机制的运行方式、存在问题及优化方向

我国自2020年开始在全国试点高校开展“强基计划”,并要求各高校在“强基计划”实施过程中建立科学化、多阶段的动态进出机制。建立“强基计划”动态进出机制能够有效提升高校拔尖创新人才的培养质量,完善高校内部质量保障体系。目前各试点高校已初步建立“强基计划”动态进出机制,主要采取转专业、分流退出和选拔补入三种主要运行方式。在实践过程中各试点高校的动态进出机制仍然存在计划性过强,缺乏科学的理论支撑,对流入和流出学生的后续培养关注不足等问题。为进一步提高“强基计划”动态进出机制的实施效果,建议加快理论生产、增加动态进出机制建立和运行的理论依据,加强相关主体的协同、提高动态进出机制的运行效果,深化实践探索、加快动态进出机制的保障和完善。

粮食智能出入库系统配套设备标准化研究

粮食仓储信息化和数字化已成为当前粮食行业实现创新和发展的必然趋势。针对粮食出入库系统存在的设计不规范、建设不系统、标准不统一等问题,中储粮集团建设了粮食智能出入库系统,对该系统在登记、扦样、检验、检斤、卸车和结算等粮食出入库各业务流程中的配套设备的标准化进行了一系列探索和实践,通过统一技术要求实现了配套设备的互联互通,具有较强的应用价值和示范意义。

火星探测热防护系统传感测量技术进展与启示

当前对于火星进入、下降与着陆过程(entry,descent and landing,EDL)气动环境认知不足,任务风险高。在EDL系统上搭载传感仪器进行飞行数据测量,重建火星大气和气动热环境,并开展充分全面的地面验证是验证科学设计工具和降低未来火星EDL任务风险的有效途径,对任务成功与否至关重要。本文首先回顾了人类火星探测任务的发展历程,明确设置热防护传感系统的必要性;然后系统总结了美国两次火星着陆任务MSL、Mars 2020,欧洲ExoMars2016任务和中国天问一号任务所搭载的EDL热防护传感系统的体系构成,以及为满足任务要求,如何进行仪器选择与布局;归纳了4次任务飞行数据的重建方法、关键技术和结果结论;最后给出了EDL热防护传感系统总结的经验、面临的技术难题和未来发展建议。

重要数据出境安全评估制度的偏离与修正

数据分类分级保护制度下,重要数据是内蕴国家安全与公共利益的数据类型。数据出境监管规则体系中,安全评估的功能定位系防范整体安全风险。而我国重要数据出境安全评估制度却偏离了聚焦整体安全的理念,侧重于关注个体安全。这易使数据出境监管滑向过度规制,不利于数据的流通与利用,因而亟须修正。首先,《数据出境安全评估办法》多处采取关注个体安全的法条表述应被修改。其次,个人信息集群型重要数据的安全评估门槛过低,应适当提升,并从国家安全层面界定个人信息敏感性。再次,殷鉴欧盟充分性认定的“中国版充分性认定”仍难适用于重要数据的出境监管,理应摒弃“实质等同”逻辑并进一步细化考量因素。最后,标准合同条款在重要数据出境场景下存在适用障碍,应专门制定针对性的重要数据出境示范合同条款,与适用于小规模个人信息出境的标准合同条款并列,使数据出境监管规则体系更适恰于数据出境监管实践需要。

基于自主作业的农业机械动态路径规划方法研究

针对无人农场中农机从下田点到初始作业位置以及从终止作业位置到下田点的自主行驶需求,提出了基于自主作业的农业机械动态路径规划方法。该方法将农机行驶路径明确划分为工作路径和非工作路径,并深入阐述了非工作路径中进入路径和退出路径的生成原理。为验证该方法的可行性,选取了4个典型的凸多边形地块进行了实际测试。实验结果表明,所规划的路径完全满足农机自主进入和退出地块的要求,确保了农机在无人农场中的高效、自主作业。

输日实验动物检疫监管政策的解析与思考

日本是我国进出口实验动物的主要贸易伙伴之一,对于实验动物的进出口检疫监管政策十分细致而严格。本文以实验犬、猫和猴为例,对出口日本的主要实验动物检疫监管政策进行了深入解析,同时对我国目前实验动物相关的法律法规、进出境管理办法、标准、生物安全、养殖和管理现状以及进出口业务现状展开思考,在完善实验动物法律法规和进出境管理办法、保障国门生物安全、提高实验动物养殖管理水平以及促进实验动物进出口贸易等方面给出了建议,以期为全面提升我国实验动物生产、使用、养殖管理水平,加强中日实验动物贸易往来提供参考。

东北三省战略性新兴产业企业进入与退出的时空格局及影响机理

基于企业数据,结合核密度估计、标准差椭圆和地理探测器方法,分析2009—2022年东北三省战略性新兴产业企业进入和退出的时空格局演变及影响机理。结果表明:(1)东北三省战略性新兴产业企业进入与退出均具有较强的中心城市指向性。(2)资源型城市的产业发展呈现渐进式稳定发展态势。(3)企业进入空间演化形成“多核心-外围”格局,退出形成“单核心-多核心-外围”演化格局,进而影响重心转移轨迹,进入重心逐渐南移,退出重心逐渐北移。(4)产业、区域和政策关联的共同作用塑造了东北三省战略性新兴产业企业进退格局。