Shutting the Door

China pledges to crack down on counterfeit products to Africa MANY people who have traveled in Africa and visited some of many Chinese retail outlets across the continent have encountered cheap fake items on the shelves,which not only present a bad image of China’s manufacturing abilities but also infringe on the intellectual property rights of others.

Transient Hydraulic Performance and Numerical Simulation of a Centrifugal Pump with an Open Impeller during Shutting Down

In this paper, the transient behavior of a low specific speed centrifugal pump with straight blades during shutting down is studied through the experimental test, theoretical calculation, and numerical simulation. The variations of the rota- tional speed, flow rate, and head with time are obtained in experiment. Based on the experimental results of the rota- tional speed and flow rate, the additional theoretical heads are quantitatively calculated and analyzed. The experimental results of the rotational speed and flow rate are worked as the boundary conditions to accurately accomplish the nu- merical simulation of the transient flow during shutting down. The experimental results show that the decrease history of the flow rate evidently lags behind that of the rotational speed, while the rotational speed slightly lags behind the head. Theoretical analysis shows that there exists a clear negative head impact phenomenon in the process of stopping. The transient behavior of the centrifugal pump with straight blades mainly comes from the rotation deceleration of im- peller, and has nothing to do with the fluid deceleration. The numerical simulations show that a large area backflow can be seen when the rotational speed decreases to zero due to the flowing inertia. In conclusion, the numerical simulation of the flow field is in good agreement with the internal flow theory of centrifugal pumps.

Microstructure and defect of titanium alloy electron beam deep penetration welded joint

The microstructure, phase composition and cold shut defect of thick titanium alloy electron beam welded joint were studied. The results showed that the microstructure of weld zone was composed of α′ phase; the heat affected zone was divided into fine-grained zone and coarse-grained zone, the microstructure of fine-grained zone was primary α phase ＋ β phase ＋ equiaxed α phase, and the microstructure of coarse-grained zone was primary α phase ＋ acicular α′ phase; the microstructure of base metal zone basically consisted of primary α phase, and a small amount of residual β phase sprinkled. The forming. reason of cold shut was analyzed, and the precaution of cold shut was proposed.

On-site raw gas cut-off during the shut down of Baosteel phaseⅠcoke ovens

The preparation and implementation of raw coke oven gas cut-off, which was the key process involved with shutting down the Baosteel phase I coke ovens, were investigated, and the main technical points and countermeasures are presented.

基于通用荧光标签的microRNA芯片检测平台

microRNA(miRNA)是一类生物内源性非编码小RNA分子,在细胞的生长、发育、增殖和细胞凋亡中具有重要的调控作用,并且与癌症的发生息息相关.miRNA表达谱是miRNA研究中的一个关键环节,使用芯片技术分析miRNA表达谱通常要求对miRNA样品进行耗时耗力的荧光标记,并且常规的芯片技术难以精确识别高度同源的miRNAs分子.为了解决以上问题,本实验室建立了一个被命名为SHUT(Stacking-hybridized Universal Tag)的新型非标记miRNA芯片分析方法.本文通过分别使用两步杂交法、一步杂交法对SHUT平台的miRNAs特异性检测进行优化.研究结果表明,SHUT平台在48℃下杂交18 h,除了let-7b和P-let-7c,let-7c和P-let-7a分别存在超过32.5%和83.3%的假阳性信号之外,其它交叉杂交信号都低于10%,具有较好的特异性.在该杂交条件下,靶标分子let-7d的最低检测浓度为20 fmol/L,并且在20 fmol/L至200 pmol/L之间具有较好的线性关系.

Confluence and cold shut computation based on time field in casting simulation

Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of liquid metal streams.The main filling-related defects are cold shut defects.To calculate the positions of casting defects,the characteristics of liquid metal confluences were analyzed.The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field,which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams.To distinguish small confluences from the main confluences,the concept of confluent scale was developed,which was used to filter the small confluences based on a threshold.The calculation process was demonstrated through the post-processing of numerical simulation.A "W" shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study.The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams.The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting.The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan.

一种汽车侧部铰链门洞密封面设计及优化介绍

在汽车设计中,汽车的乘客舱门密封面设计既是一个要点,也是一个难点,对于提升车身品质和质量细节具有关键作用。文章对汽车侧门门洞(乘客舱)密封面的设计及优化进行了介绍,包括车门系统如何布置、密封面何时开始绘制、密封面的优化方法、密封面的lessons learn等。

VPLS网络常见故障分析及对策

从一例VPLS网络入手,分析了针对单个VPN的单个用户或者多个或者所有该VSI下的用户出现的常见问题及处理对策。

Research on main circuit parameter coupling relationship of single-phase shunt active power filter

There is a certain coupling relationship among the main circuit parameters of a single-phase shunt active power filter(SAPF),which has a great influence on the reasonable selection of various parameter values.By analyzing the calculation methods of the inductance of alternating current(AC)side and the voltage and capacitance values of direct current(DC)side in the existing single/three-phase SAPF main circuit,a specific single-phase SAPF circuit parameter analytical expression was obtained.Aiming at the coupling relationship among the variables in the resulting expression,the model was optimized and analyzed in MATLAB,and a complete set of parameters design scheme was obtained,which ensure the comprehensive optimization target of the post-harmonic content below 2% is compensated under a specific load.The simulation and experimental procedures verify the correctness of the selected parameters.

Analysis of Factors Influencing Shut in Pressure Cone in Offshore Strong Bottom Water Reservoir

X oilfield is an offshore strong bottom water reservoir with water cut up to 96% at present, and liquid extraction has become one of the main ways to increase oil production. However, the current liquid production of the oilfield reaches 60,000 m3/d due to the limitation of offshore platform, well trough and equipment, the oilfield is unable to continue liquid extraction. In order to maximize the oil production of the oilfield, it is necessary to study the strategy of shut in and cone pressure. Through numerical simulation, this paper analyzes the influence of different factors, such as crude oil density, viscosity, reservoir thickness, interlayer, permeability and so on, on the drop height of water cone and the effect of precipitation and oil increase after well shut in. At the same time, the weight of each factor is analyzed by combining the actual dynamic data with the fuzzy mathematics method, and the strategy of well shut in and cone pressure is formulated for the offshore strong bottom water reservoir. It provides the basis and guidance for the reasonable use of shut in pressure cone when the reservoir with strong bottom water meets the bottleneck of liquid volume.

一种汽车侧部铰链门洞密封面设计及优化介绍

文章介绍了某汽车公司的一款MPV车型侧门门洞密封面设计所使用的方法和相关要求：门洞B＆R line是车型结构开发设计过程中的重要边界：侧围SHUTFACE面的输出包含了门洞B＆R line，包含了主密封和二道密封尺寸约束关系，体现了大部分门系统功能件布置所需的要求和周边关系：该密封面需要项目开发前期组织各相关区域讨论确认，尽早完善功能结构和沟通达成一致，然后锁定发布边界更新数模；虽然经过优化和讨论确认，但也永远没有最完美的密封面，只有满足项目开发时间、功能结构布置、感知等综合要求的输出物才是最优的。

Open and Shut Up

Doctor: Please open your wouth,madam.Lady:Thank you

采用非标记microRNA芯片筛选早产胎盘差异表达microRNA

目的应用非标记microRNA芯片筛选在早产胎盘组织中差异表达的miRNA,并分析其相关的靶基因。方法收集早产儿16例为病例组,同期健康足月产儿18例为对照组,取胎盘组织。通过非标记miRNA芯片技术构建早产胎盘组织miRNA表达谱,采用荧光实时定量PCR进行验证,并分析差异表达miRNAs的靶基因。结果 miRNA芯片结果显示44种miRNAs在早产胎盘组织和对照组胎盘组织中差异表达,其中下调表达的11种,上调表达的33种,荧光实时定量PCR验证出miR-493-3p显著下调,mi R-4632-5p显著上调,与芯片结果一致。经软件分析,miRNA靶基因有IL16、SH2D2A、CCNG2、PHB、WNT1、CCDC92、GIT1和ST7L等相关靶基因。结论早产胎盘组织中存在差异表达的miRNAs,提示这些差异表达的miRNAs在早产的发生中有重要的调控作用。

Gold glitters everywhere: nucleus microRNAs and their functions

As a highly conserved class of endogenous small(~22 nucleotides)non-coding RNAs,microRNAs(miRNAs)regulate a broad spectrum of biological processes.Increasing evidences suggested that miRNAs generally regulated gene expression at the posttranscriptional stage via inhibiting the translational process or degrading mRNA.Recent studies have also revealed that there is extensive amount of miRNA,as well as miRNA function-related proteins,in the cell nucleus.Although the molecular basis underneath the biogenesis and function of nucleus miRNAs remains largely unknown,the presence of various miRNAs and miRNA function-related proteins in the nucleus strongly argue that miRNAs may execute their role throughout the whole gene expression pathway.Here we review the recent advances in the researches about the nucleus miRNAs,including the biosynthesis pathways,biological functions and potential regulation machinery of nucleus miRNAs.

Optimization of cloud load balancing using fitness function and duopoly theory

Purpose-Current industrial scenario is largely dependent on cloud computing paradigms.On-demand services provided by cloud data centre are paid as per use.Hence,it is very important to make use of the allocated resources to the maximum.The resource utilization is highly dependent on the allocation of resources to the incoming request.The allocation of requests is done with respect to the physical machines present in the datacenter.While allocating the tasks to these physical machines,it needs to be allocated in such a way that no physical machine is underutilized or over loaded.To make sure of this,optimal load balancing is very important.Design/methodology/approach-The paper proposes an algorithm which makes use of the fitness functions and duopoly game theory to allocate the tasks to the physical machines which can handle the resource requirement of the incoming tasks.The major focus of the proposed work is to optimize the load balancing in a datacenter.When optimization happens,none of the physical machine is neither overloaded nor under-utilized,hence resulting in efficient utilization of the resources.Findings-The performance of the proposed algorithm is compared with different existing load balancing algorithms such as round-robin load(RR)ant colony optimization(ACO),artificial bee colony(ABC)with respect to the selected parameters response time,virtual machine migrations,host shut down and energy consumption.All the four parameters gave a positive result when the algorithm is simulated.Originality/value-The contribution of this paper is towards the domain of cloud load balancing.The paper is proposing a novel approach to optimize the cloud load balancing process.The results obtained show that response time,virtual machine migrations,host shut down and energy consumption are reduced in comparison to few of the existing algorithms selected for the study.The proposed algorithm based on the duopoly function and fitness function brings in an optimized performance compared to the four algorithms analysed.

Eyes Wide Shut

First impressions, they say, count for everything.This may be true in some cases, especially those in which one doesn’t have

拥抱变化? Shut up! 2016探讨如何赌对“不变”

TED演讲没有开头,总是上来就直奔主题。我猜测类似做法是希望尽量免去那些“完全正确”的废话,从而让更有价值的信息能够被凸显。有些废话,像去任一行业会议都能听到的“2016机遇大于挑战”一样,不仅毫无意义,其真实性也很值得怀疑。现实情况是：2016对大多数营销人来说,挑战大于机遇,这将是非常艰难的一年。最大的艰难可能来自信息的粉尘化。