中日义务教育阶段教师流动程序的比较研究

义务教育阶段教师合理流动是推进教师资源均衡配置的有益尝试,是保证受教育者公平地享有受教育权的重要举措。教师流动程序的规范和公正既是教师、学校和教育行政部门实施流动行为的需要,也是尊重教师流动意愿、重视教师选择流动学校的需要。日本教师流动程序的立法比较完善,流动行为有法可依,有章可循。分析比较中日义务教育阶段教师流动程序的异同,有利于参考日本制定流动程序的成功经验和教训,完善我国的教师流动程序。

高温灰渣在斜面冷渣器中的流动分析

为了分析工业生产中的高温灰渣在斜面上的流动特性,采用基于离散单元法的颗粒流动程序（PFC2D）,建立料仓和斜面的仿真模型,首先分析颗粒通过斜面的临界角,然后针对颗粒在不同斜面倾角,进行了颗粒运动的数值模拟,为下一步分析颗粒传热做准备.通过模拟发现：①颗粒通过斜面的临界角为28°～ 29°;②在斜面倾角大于临界角的前提下,颗粒的堆积厚度随着通过斜面的距离的增大而减小,堆积厚度拟合直线的斜率逐渐增大,在40°之前呈现直线增长的趋势,40°～50°增长速度逐渐平缓,拟合直线的截距随着倾角的增大,逐渐较小.

RFQ电极参数计算和加工程序——RFQPOLE

介绍了RFQ加速器电极参数计算程序FRQPOLE。该程序可以直接调用RFQ束流动力学计算程序PARMTEQ的输出文件 ,采用准正弦近似求出加速器电极极面参数随纵向位置z的关系。然后以北京大学 2 6MHz 1MeVO+ 的微翼型RFQ电极为例进行了计算 ,求解出电极极面参数后给出直观的电极图形和铣刀模拟加工过程。

库房管理物品流程的改革

从唐山工业职业技术学院搬迁到新校区,在库房管理物品流动中存在的问题出发,叙述了科学合理物品的摆放方法和数据处理方法,重点阐述了物品流动程序的改革,提高了物流速度,减少物流中的漏洞,为高效、快捷库房管理提供科学手段。

An Accurate and Extensible Machine Learning Classifier for Flow-Level Traffic Classification

Machine Learning(ML) techniques have been widely applied in recent traffic classification.However, the problems of both discriminator bias and class imbalance decrease the accuracies of ML based traffic classifier. In this paper, we propose an accurate and extensible traffic classifier. Specifically, to address the discriminator bias issue, our classifier is built by making an optimal cascade of binary sub-classifiers, where each binary sub-classifier is trained independently with the discriminators used for identifying application specific traffic. Moreover, to balance a training dataset,we apply SMOTE algorithm in generating artificial training samples for minority classes.We evaluate our classifier on two datasets collected from different network border routers.Compared with the previous multi-class traffic classifiers built in one-time training process,our classifier achieves much higher F-Measure and AUC for each application.

A General Formula of Flow Equations for Harry-Dym Hierarchy

In this paper, we derive a general formula of the flow equtions for the Harry-Dym hierarchy. And three applications in n-reduction, （2 ＋ 1）-dimensional generalization, and Kupershmidt reduction, are considered.

Design and Implementation of an Adaptive Feedback Queue Algorithm over Open Flow Networks

The concurrent presence of different types of traffic in multimedia applications might aggravate a burden on the underlying data network, which is bound to affect the transmission quality of the specified traffic. Recently, several proposals for fulfilling the quality of service(QoS) guarantees have been presented. However, they can only support coarse-grained QoS with no guarantee of throughput, jitter, delay or loss rate for different applications. To address these more challenging problems, an adaptive scheduling algorithm for Parallel data Processing with Multiple Feedback(PPMF) queues based on software defined networks(SDN) is proposed in this paper, which can guarantee the quality of service of high priority traffic in multimedia applications. PPMF combines the queue bandwidth feedback mechanism to realise the automatic adjustment of the queue bandwidth according to the priority of the packet and network conditions, which can effectively solve the problem of network congestion that has been experienced by some queues for a long time. Experimental results show PPMF significantly outperforms other existing scheduling approaches in achieving 35--80% improvement on average time delay by adjusting the bandwidth adaptively, thus ensuring the transmission quality of the specified traffic and avoiding effectively network congestion.

The Thermal and Mechanical Properties of Ultra-High Molecular Weight Polyethylene/Montmorillonite (UHMWPE/MMT) Nanocomposites Hybrid Gel Using Pressure-Induced Flow (PIF) Processing

Hybrid organic-inorganic polymer nanocomposites incorporating organically modified montmorillonite (MMT) and ultra-high molecular weight polyethylene (UHMWPE) were examined. UHMWPE/MMT hybrid nanocomposites were prepared using gel and pressure-induced flow(PIF) processing methods at a gel weight concentration of 8% UHMWPE with various organoclay contents (0, 0.4, 0.8, 1.2, and 1.6 parts per hundred parts). The interlayer properties of the nanocomposites were studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The thermal and mechanical interfacial properties of the nanocomposites were investigated through thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and the use of a universal test machine (UTM). TEM indicates that the nanocomposites are formed upon dispersion of MMT in the polymer matrix. From the DSC, TGA, and DMA results, we find that the thermal stability of the UHMWPE nanocomposites increases as the MMT content increases. The nanocomposites show higher tensile strengths than pure UHMWPE gel sheet. These findings indicate that the interfacial and mechanical properties are improved by the addition of MMT and PIF processing.

A CFD model for gas uniform distribution in turbulent flow for the production of titanium pigment in chloride process

The fluid dynamic behavior of feeding gas （TiCI4） in an annular channel affects the combination of 02 and TiCI4 in an oxidation reactor, a key piece of equipment in titanium pigment production. The numerical procedure was validated by a 3-dimensional gas flow in the annular channel. Applying the validated model, the flow character- istics of TiCl4 in the oxidation reactor with a tangential inlet were simulated and characterized. The flow distribu- tion with five rectifying rings of different structure was simulated and analyzed. The results showed that the rectifying ring improved the distribution uniformity of the pressure and outlet velocity. Compared to the original case without a rectifying ring, the non-uniformity of the pressure and outlet velocity could be reduced by up to 91% and 69% respectively. The rectifying ring #5, which can be installed and adjusted easily, is more effective in realizing even distribution. In addition, installation of the rectifying ring effectively reduced the circulating flow in an annular channel as well as the total energy loss.

Cellular Automaton Simulation of Evacuation Process in Story

Computer simulations on the evacuation process in a story are launched with cellular automaton in this article. The story is composed of five rooms and one corridor. Influence of various parameters on the evacuation process is investigated. It shows that the width of the door of rooms has little influence but the width of the corridor and the maximum velocity of the pedestrian have great influence on the time for evacuation. The relation between evacuation time and the width of corridor is found as tc ∝ W^-0.84. It is also found that appropriate shape of the room is helpful to evacuation.

The Attributes of Social Media as a Strategic Marketing Communication Tool

New digital trends are transforming the media industry landscape, modifying elemental characteristics and attitudes of companies as well as of consumers. Firms often claim that their presence in social media （SM） is a key element to success. SM helps companies rethink the traditional one-way flow of their marketing messages and to incorporate a new interactive pattern into their communications. Nevertheless, these tendencies involve problems of strategic myopia for firms that do not structurally integrate these tools. One main problem is that institutions can rarely differentiate between the various types of SM and the attributes thereof, while the literature equally reveals a number of contradictions in the subject. The present conceptual paper lays the foundations of a strategic approach to SM and discusses its theoretical implications. Following an overview on the concept of SM, through a content analysis of the specialized management literature （n = 14）, we present various best practices and reflect on the apparent lack of strategic thinking in using SM as a marketing application. Then, we compare these practical examples with general marketing strategy theory. By merging theory and practice, we aim to provide an insight towards a well-founded application of SM as a genuinely strategic marketing tool.

Work Organization at Farm Level： A Process-Led Approach to Understand Land Use Changes

In the French Alps, some grasslands have been abandoned, others are invaded by scrub whereas they are still used by farmers What are the relationships between land use changes and other changes at farm level that lead to scrub invasion？ We hypothesize that they are linked by two work organization processes： process of changes （changes in the household and farm） leading to less intensive land use; and annual processes （sequences of activities during the year） and their repetition from one year to another, leading to insufficient land maintenance. In this paper, we present a study carried out in the Northern French Alps, based on surveys with livestock farmers. It appears that land use changes are often the consequence of other changes made to address work problems, and land use sequences are defined according to workforce and prioritization of tasks. This highlights the importance of considering farmers as workers in order to evaluate land use changes at the farm level and to link them to the human dimension within farming systems.

A modified PANS model for computations of unsteady turbulence cavitating flows

A modification to the PANS(partially averaged Navier-Stokes) model is proposed to simulate unsteady cavitating flows. In the model, the parameter fk is modified to vary as a function of the ratios between the water density and the mixture density in the local flows. The objective of this study is to validate the modified model and further understand the interaction between turbulence and cavitation around a Clark-Y hydrofoil. The comparisons between the numerical and experiment results show that the modified model can be improved to predict the cavity evolution, vortex shedding frequency and the lift force fluctuating in time fairly well, as it can effectively modulate the eddy viscosity in the cavitating region and various levels of physical turbulent fluctuations are resolved. In addition, from the computational results, it is proved that cavitation phenomenon physically influences the turbulent level, especially by the vortex shedding behaviors. Also, the mean u-velocity profiles demonstrate that the attached cavity thickness can alter the local turbulent shear layer.

Relationship between the Flow Blockage of Tip Leakage Vortex and its Evolutionary Procedures inside the Rotor Passage of a Subsonic Axial Compressor

The near casing flow fields inside the rotor passage of a 1.5 stage axial compressor with different blade-loading levels and tip gap sizes were measured by using stereoscopic particle image velocimetry(SPIV). Based on a carefully defined blockage extracting method, the variations of blockage parameter inside the blade passage were analyzed. It was found that the variation of blockage parameter appeared as a non-monotonic behavior inside the blade passage in most cases. This non-monotonic behavior became much more remarkable as the blade loading increases or mass flow rate decreases.The variations of the blockage parameter inside the blade passage had close relation to the evolutionary procedures of the tip leakage vortex(TLV). The destabilization of the TLV caused a rapid increasing of the blockage parameter. After the TLV lost the features of a concentrated streamwise vortex,the blockage parameter usually got a peak value. And then, because of the intense turbulent mixing between the TLV low momentum flow and its surrounding flows, the flow deficit inside the TLV recovered.

On the Kahler-Ricci Flow on Projective Manifolds of General Type

This note concerns the global existence and convergence of the solution for Kahler-Ricci flow equation when the canonical class, Kx, is numerically effective and big. We clarify some known results regarding this flow on projective manifolds of general type and also show some new observations and refined results.

Sexual selection and magic traits in speciation with gene flow

The extent to which sexual selection is involved in speciation with gene flow remains an open question and the sub- ject of much research. Here, we propose that some insight can be gained from considering the concept of magic traits （i.e., traits involved in both reproductive isolation and ecological divergence）. Both magic traits and other, ＂non-magic＂, traits can contribute to speciation via a number of specific mechanisms. We argue that many of these mechanisms are likely to differ widely in the ex- tent to which they involve sexual selection. Furthermore, in some cases where sexual selection is present, it may be prone to in- hibit rather than drive speciation. Finally, there are a priori reasons to believe that certain categories of traits are much more ef- fective than others in driving speciation. The combination of these points suggests a classification of traits that may shed light on the broader role of sexual selection in speciation with gene flow. In particular, we suggest that sexual selection can act as a driver of speciation in some scenarios, but may play a negligible role in potentially common categories of magic traits, and may be likely to inhibit speciation in common categories of non-magic traits [Current Zoology 58 （3）： 510-516, 2012].

Application of Program Generation Technology in Solving Heat and Flow Problems

Based on a new DIY concept for software development, an automatic program-generating technology attached on a software system called as Finite Element Program Generator （FEPG） provides a platform of developing programs, through which a scientific researcher can submit his special physico-mathematical problem to the system in a more direct and convenient way for solution. For solving flow and heat problems by using finite element method, the stabilization technologies and fraction-step methods are adopted to overcome the numerical difficul- ties caused mainly due to the dominated convection. A couple of benchmark problems are given in this paper as examples to illustrate the usage and the superiority of the automatic program generation technique, including the flow in a lid-driven cavity, the starting flow in a circular pipe, the natural convection in a square cavity, and the flow past a circular cylinder, etc. They are also shown as the verification of the algorithms.