Velocity

摘要： The flow field or multidimensional velocity distribution of the coolant in fuel rod bundles of the reactor core in pressurized water reactors (PWRs) is an important parameter that is revealed through experimental investigations. This paper presents the two-dimensional (2D) velocity profile measurement using a two-element ultrasonic transducer with both elements acting as a transceiver. The size of the transducer is minimized for compactness, leading to a narrow sound field appropriate for applications in fuel rod bundle flow. Furthermore, the transducer’s sound pressure is evaluated via simulations and experimental measurements. In order to confirm the ability of the ultrasonic velocity profiler (UVP) with a two-element transducer, the experimental measurement is conducted in turbulent horizontal pipe flow. The 2D velocity vector profile is obtained, and then the measurement in swirling flow is conducted. The 2D velocity profile in an axial and radial plane is obtained utilizing the UVP measurement. Lastly, the ability of the UVP to derive the 2D velocity profile in the narrow area of the rod bundles is demonstrated.

摘要： The pathogen plays an important role in spreading infection and bad impact on the public health of the river. Therefore, water quality as a model is used to simulate the spreading and fate of the pathogen in Lijiang River, it is located in Lijiang City, Yunnan Province, China (100°25'E, 26°86'N). Even at low bacterial levels, there is a risk of pathogens in the Lijiang River ecosystem. The water quality model results showed that the spatiotemporal (space and time) migration of pathogenic bacteria in Lijiang River from 2005 to 2015 was quantitatively revealed by the model simulation. The simulation results also showed that the transports of pathogenic bacteria in Lijiang River are extremely sensitive to the speed distribution and seasonal temperature characteristics. The study found that the rising water temperature in spring leads to a sharp rise in the concentration of pathogenic bacteria. When the water temperature is low in winter, the simulated pathogenic bacteria are relatively stable, which is lower than the concentration of pathogenic bacteria at high temperature. If the spring water temperature rises, the flow rate increases, the concentration of pathogenic bacteria accordingly increases. This research recommends the development of best management practices to control microbial growth in river basins.

摘要： 近年来,随着互联网、云计算和物联网技术的快速发展,数据规模急剧扩大,大数据应运而生[1]。作为一个新生概念,大数据是通过分析海量信息,进而发现规律、收集有价值的见解以及预测复杂问题答案的技术和科学,可用来解决数据再利用的问题。其基本特征表现为Volume(数据量大)、Variety(数据类型多)、Velocity(数据创建、处理和分析的速度快)和Veracity(数据不确定)[2]。

摘要： Breaststroke kick pattern is different from elite breaststrokers to none elite breaststrokers.We analyzed breaststroke kick of knee angles and hip angles from FINA(Fédération internationale de natation)former world record holder,Olympians,World Championship,The International Swimming League(ISL)and NCAA(the National Collegiate Athletic Association)Division 1 championship qualifier.Previous study explored the 1990’s breaststroke kick is very powerful because swimmers can push water back with the soles of their feet for a long period of time.We assess the effectiveness of utilizing a downward kick in the breaststroke with regard to the overall time,max speed,tempo,and velocity when using a downward breaststroke kick technique.We hypothesize that a significant proportion of the improvement is due to the downward breaststroke kick used in breaststroke competitions which resulted in a time improvement in the men’s 100-yard record from 57.04s to 53.69s.Using a downward breaststroke kick in individual medley competition resulted in improvements from 1:15.42s to 1:13.50s in 100-m breaststroke split time men’s 400-m individual medley.We find the introduction of the downward kick in the breaststroke kick is primarily responsible for this improvement in time.

摘要： 数据智能曾被看做是各个行业的催化剂,不属于基础建设领域。但现在,数据智能领域已经成为了一个重要的基础建设领域。我们对大数据的理解最初来源于4个“V”,即真实性(Veracity)、大量化(Volume)、速度化(Velocity)、多样化(Variety)。现在大家对4个“V”这个概念的理解已经不尽相同。我们把真实性换成了价值密度(Value density)这种特性,因为我们认为只有价值密度低的数据才是大数据。如果价值密度较高,数据就不能被称作是大数据,而应该被叫做结果数据,因为这些数据无法进行进一步地多维分析。只有对价值密度非常低的数据进行多维分析,才有可能产生有影响力的结果。

摘要： BACKGROUND Single umbilical artery(SUA)is the most common umbilical cord malformation in prenatal diagnosis.The presence of an SUA can cause blood circulation disorder in the foetus and functional changes of the foetal heart,affecting foetal circulation.The right ventricular diastolic functions in foetuses with isolated SUA and in normal foetuses in the third trimester were evaluated using the spectral Doppler of blood flow in the foetal ductus venosus(DV).AIM To evaluate the right ventricular diastolic functions in foetuses with isolated SUA and in normal foetuses in the third trimester.METHODS Colour Doppler was used to measure the spectrum of foetal DV and tricuspid orifice in 34 foetuses with isolated SUA aged 28-39 wk and in age-matched healthy controls.The DV flow velocities and velocity ratios were measured.The early passive/late active(E/A)ratio at the tricuspid orifice and tissue Doppler Tei index of the foetal right ventricular in the two groups were also measured.RESULTS During the third trimester,the isolated SUA group showed a lower‘a’-wave peak velocity in the DV than the control group(P<0.05).The correlations between the velocity ratios and E/A ratio at the tricuspid orifice in the two groups were analysed,and the correlation between the ventricular late diastolic velocity/ventricular diastolic peak flow velocity and E/A ratios was the best(R^2of the isolated SUA group:0.520;R2 of the control group:0.358).The correlations between the velocity ratios and tissue Doppler Tei index of foetal right ventricular in the two groups were analysed,and the correlation between the pulsatility index for veins(PIV)and tissue Doppler Tei index ratios was the best(R2 of the isolated SUA group:0.865;R2 of the control group:0.627).CONCLUSION In the isolated SUA group,the atrial systolic peak velocity‘a’decreased,and this finding might be related to the changes in foetal cardiac functions.The ratio of ventricular late diastolic velocity to ventricular diastolic peak flow velocity was closely related to the E/A ratio at the tricuspid valve and can be used to identify changes in the right ventricular diastolic functions of isolated SUA and healthy foetuses.PIV was closely related to the tissue Doppler Tei index of the foetal right ventricular and can be used to identify the right ventricular overall functions of isolated SUA and healthy foetuses.

摘要： 就在上个月英特尔发布了全新的第十代酷睿高性能版处理器,此次推出的使用英特尔Thermal Velocity Boost的酷睿i9-10980HK和i7-10875H,其中酷睿i9-10980HK一举将单核睿频最高提升到了5.3GHz,采用八核心十六线程以及16MB智能高速缓存。而此前,英特尔也先后推出多款H后缀结尾的高性能移动版处理器。作为今年上半年最值得期待的移动版处理器,英特尔酷睿十代高性能移动版,必将引领高端笔记本和游戏笔记本细分市场的新一轮消费热情。今天我们就为大家带来了首批搭载第十代英特尔酷睿处理器的游戏本Acer暗影骑士·擎,和大家一起见证十代酷睿游戏本的全新升级使用体验。

摘要： To deal with the problem that the initial velocity of the bullet is difficult to increase,the research on the super-high initial velocity propulsion in the barrel weapon with an adaptive pressure-maintaining chamber are conducted.Considering the law of gun-powder burning and the flow characteristics of gun-powder gas in multi-chamber,the scheme of super-high initial velocity propulsion with an adaptive pressure-maintaining chamber is designed,the ballistic model of the barrel weapon with super-high velocity bullet propulsion is established.The research results show that the technical scheme can greatly increase the initial velocity of the bullet with the peak pressure keeping nearly the same as the tradition barrel weapon.The research results can provide a theoretical foundation to significantly increase the initial velocity in barrel weapons using solid propellants,and have an important reference value to comprehensively increase the power of the barrel weapons.

摘要： Oral 4-aminopyridine(4-AP)is clinically used for symptomatic relief in multiple sclerosis and we recently demonstrated that systemic 4-AP had previously unknown clinically-relevant effects after traumatic peripheral nerve injury including the promotion of re-myelination,improvement of nerve conductivity,and acceleration of functional recovery.We hypothesized that,instead of oral or injection administration,transdermal 4-AP(TD-4-AP)could also improve functional recovery after traumatic peripheral nerve injury.Mice with surgical traumatic peripheral nerve injury received TD-4AP or vehicle alone and were examined for skin permeability,pharmacokinetics,functional,electrophysiological,and nerve morphological properties.4-AP showed linear pharmacokinetics and the maximum plasma 4-AP concentrations were proportional to TD-4-AP dose.While a single dose of TD-4-AP administration demonstrated rapid transient improvement in motor function,chronic TD-4-AP treatment significantly improved motor function and nerve conduction and these effects were associated with fewer degenerating axons and thicker myelin sheaths than those from vehicle controls.These findings provide direct evidence for the potential transdermal applicability of 4-AP and demonstrate that 4-AP delivered through the skin can enhance in-vivo functional recovery and nerve conduction while decreasing axonal degeneration.The animal experiments were approved by the University Committee on Animal Research(UCAR)at the University of Rochester(UCAR-2009-019)on March 31,2017.

摘要： 基于模板的代码生成方法克服了基于XML/XSLT方法的性能、模型分割等不足之处,适用于MDA代码生成框架.这种方法使用在基于MDA的电子商务开发平台开发过程中,提高了开发和维护的效率,并且在具体的电子商务网站开发项目中取得了成功.

摘要： 基于模板的代码生成方法克服了基于XML/XSLT方法的性能、模型分割等不足之处,适用于MDA代码生成框架.这种方法使用在基于MDA的电子商务开发平台开发过程中,提高了开发和维护的效率,并且在具体的电子商务网站开发项目中取得了成功.

摘要： 基于模板的代码生成方法克服了基于XML/XSLT方法的性能、模型分割等不足之处,适用于MDA代码生成框架.这种方法使用在基于MDA的电子商务开发平台开发过程中,提高了开发和维护的效率,并且在具体的电子商务网站开发项目中取得了成功.

摘要： 基于模板的代码生成方法克服了基于XML/XSLT方法的性能、模型分割等不足之处,适用于MDA代码生成框架.这种方法使用在基于MDA的电子商务开发平台开发过程中,提高了开发和维护的效率,并且在具体的电子商务网站开发项目中取得了成功.

摘要： 本发明公开了一种在服务器中基于Velocity块指令的局部缓存方法，包括：接收客户端发送的访问具有Velocity块指令的超文本标记语言HTML页面的请求；在缓存中检查客户端请求的与Velocity块指令有关的数据是否更新；以及向客户端返回更新状态和缓存键值。

摘要： 本公开涉及一种基于Velocity模板引擎的数据库表结构翻译方法和装置；其中，方法包括：构建异构数据库之间的目标格式转换文件，基于目标接口获取源端的表字段信息，初始化Velocity后，构建Velocity上下文对象，将表字段信息输入Velocity上下文对象，在Velocity中加载目标格式转换文件对Velocity上下文对象中的表字段信息进行处理，得到表结构翻译结果并发送给目标端。由此，通过采用Velocity模板引擎进行表结构翻译，提高表结构翻译效率和准确性。

摘要： 本发明公开了一种在服务器中基于Velocity块指令的局部缓存方法，包括：接收客户端发送的访问具有Velocity块指令的超文本标记语言HTML页面的请求；在缓存中检查客户端请求的与Velocity块指令有关的数据是否更新；以及向客户端返回更新状态和缓存键值。

摘要： 本发明公开一种基于velocity可定制的代码生成方法和系统，涉及简化代码开发技术领域；提取元数据，归一化处理所述元数据，并获取所述元数据的附属参数，定义代码生成的velocity模板，设置所述velocity模板及生成文件的关系，调用velocity的api，传入所述元数据、所述附属参数及所述velocity模板，生成代码，进行代码合并提交至相关业务工程中。