中包过热度、钙硫质量比、轧制变形量对中碳石油套管钢低温冲击韧性的影响

通过改变中包过热度(20,40℃)、钢液中钙硫质量比(0~0.9)、粗轧单道次变形量(14%,20%)、中间坯厚度(49,52,53 mm)、精轧后三道累积变形量(29%,34%)生产中碳石油套管钢,分析了中包过热度、轧制变形量和钙硫质量比对试验钢组织和-10℃冲击功的影响。结果表明:在中包过热度为20℃下连铸铸坯的中心偏析和碳元素偏析减轻,由线链状分布变为点状分布;轧制变形量越大,试验钢晶粒尺寸越小、带状组织级别越低、低温冲击功越大;随着钙硫质量比增加,试验钢低温冲击功提高。较优的生产工艺参数为中包过热度20℃、钙硫质量比不小于0.4、粗轧单道次变形量20%、中间坯厚度53 mm、精轧累积变形量34%,该工艺生产的钢板中未观察到带状组织,低温冲击功远高于标准要求。

Molecular Dynamic Simulation on the Absorbing Process of Isolating and Coating of α-olefin Drag Reducing Polymer

The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles with polyurethane as coating material. The distributions of sodium laurate, sodium dodeeyl sulfate, and sodium dodeeyl benzene sulfonate on the surface of α-olefin drag reducing polymer particles were almost the same, but the bending degrees of them were obviously different. The bending degree of SLA molecules was greater than those of the other two surfactant molecules. Simulation results of absorbing and accumulating structure showed that, though hydrophobie properties of surfactant molecules were almost the same, water density around long chain sulfonate sodium was bigger than that around alkyl sulfate sodium. This property goes against useful absorbing and accumulating on the surface of α-olefin drag reducing polymer particles; simulation results of interactions of different surfactant and multiple hydroxyl compounds on surface of particles showed that, interactions of different surfaetant and one kind of multiple hydroxyl compound were similar to those of one kind of surfaetant and different multiple hydroxyl compounds. These two contrast types of interactions also exhibited the differences of absorbing distribution and closing degrees to surface of particles. The sequence of closing degrees was derived from simulation; control step of addition polymerization interaction in coating process was absorbing mass transfer process, so the more closed to surface of particle the multiple hydroxyl compounds were, the easier interactions With isoeyanate were. Simulation results represented the compatibility relationship between surfactant and multiple hydroxyl compounds. The isolating and coating processes of α-olefin drag reducing polymer were further understood on molecule and atom level through above simulation research, and based on the simulation, a referenced theoretical basis was provided for practical optimal selection and experimental preparation of α-olefin drag reducing polymer particles suspension isolation agent.

Facilitating IT outsourcing through improving buyer-vendor interaction in outsourcing life cycle

For a clear understanding of how to foster necessary attributes of partnerships that promote a closer relationship for achieving outsourcing success,this paper tries to explore the role of interaction.Based on empirical data from a logistics and procurement flat system outsourcing case and earlier research,the industrial network approach and the international marketing and purchasing interaction model are used to analyze the nature of interaction in a three-phased outsourcing life cycle,particularly,characteristics and activities of the transition phase are identified.The findings reveal that developing a relationship between partners requires an industrial network perspective.Improving the key aspects of interaction,information and knowledge sharing,communication and collaborative participation,involved in the important events of three phases would contribute to enhance the relationships performance.The key aspects of interaction should take place among the network actors and not just between buyers and vendors.

HRB400E螺纹钢筋生产实践

吕梁建龙实业公司通过对HRB400E钢筋的化学成分科学设计,对轧制过程的温度合理管控,一次性成功生产出性能合格的直条抗震钢筋。同时对连铸生产工序的中包钢液过热度水平、对结晶器铜管锥度尺寸、铜管过钢量进行合理管控,适当降低拉坯速度,杜绝了铸坯表面的“纵裂”缺陷,从根本上解决了轧材轧材表面的“细微”裂纹发生,生产出成分设计合理、组织达标、表面质量良好的高质量HRB400E钢筋,满足了市场的需求。

轧制电力角钢用Q355B钢坯生产实践

吕梁建龙炼钢厂通过对转炉冶炼制度、连铸浇铸工艺制度优化,对冶炼终点碳、温进行合理管控,强化转炉挡渣效果、吹氩效果,同时在连铸浇铸过程中实行低过热度浇铸、合理控制中间包液面、低拉速控制,生产出成分合格铸坯低倍组织达标的高质量Q355B钢坯。

A Router Based Packet Filtering Scheme for Defending Against DoS Attacks

The filter-based reactive packet filtering is a key technology in attack traffic filtering for defending against the Denial-of- Service （DOS） attacks. Two kinds of relevant schemes have been proposed as victim- end filtering and source-end filtering. The first scheme prevents attack traffic from reaching the victim, but causes the huge loss of legitimate flows due to the scarce filters （termed as collateral damages）; the other extreme scheme can obtain the sufficient filters, but severely degrades the network transmission performance due to the abused filtering routers. In this paper, we propose a router based packet filtering scheme, which provides relatively more filters while reducing the quantity of filtering touters. We implement this scheme on the emulated DoS scenarios based on the synthetic and real-world Internet topologies. Our evaluation results show that compared to the previous work, our scheme just uses 20% of its filtering routers, but only increasing less than 15 percent of its collateral damage.

SAFE:a Scalable Filter-Based Packet Filtering Scheme

Recently, attacks have become Denial-of-Service （DOS） the mainstream threat to the internet service availability. The filter-based packet filtering is a key technology to defend against such attacks. Relying on the filtering location, the proposed schemes can be grouped into Victim-end Filtering and Source-end Filtering. The first scheme uses a single filtering router to block the attack flows near the victim, but does not take the factor that the filters are scarce resource into account, which causes the huge loss of legitimate flows; considering each router could contribute a few filters, the other extreme scheme pushes the filtering location back into each attack source so as to obtain ample filters, but this may incur the severe network transmission delay due to the abused filtering routers. Therefore, in this paper, we propose a scalable filter-based packet filtering scheme to balance the number of filtering routers and the available filters. Through emulating DoS scenarios based on the synthetic and real-world Intemet topologies and further implementing the various filter-based packet filtering schemes on them, the results show that our scheme just uses fewer filtering routers to cut off all attack flows while minimizing the loss of legitimate flows.

Accelerating Packet Classification with Counting Bloom Filters for Virtual Open Flow Switching

The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance.

Solidification process and microstructure of transition layer of Cu-Al composite cast prepared by method of pouring molten aluminum

The Cu?Al composite casts were prepared by the method of pouring molten aluminum. The solidification process and themicrostructure of the transition layer were investigated during the recombination process of the liquid Al and the solid Cu. The results reveal that the microstructure of the transition layer in the Cu?Al composite cast consists of α(Al)+α(Al)?CuAl2 eutectic,α(Al)?CuAl2 eutectic, CuAl2+α(Al)?CuAl2 eutectic and Cu9Al4. Additionally, the pouring temperature, cooling mode of the Cu platesurface and start time of the forced cooling after pouring have no effect on the microstructure species. But the proportion of thevarious microstructures in the transition layer changes with the process parameters. The pure Al at the top of the transition layer startsto solidify first and then the α(Al) phase grows in a dendritic way, while the CuAl2 phase exhibits plane or cellular crystal growth from the two sides of the transition layer towards its interior. The stronger the cooling intensity of the Cu plate outer surface, the more developed the dendrite, and the easier it is for the CuAl2 phase to grow into a plane crystal.

Eosinophilic cholecystitis along with pericarditis caused by Ascaris lumbricoides: A case report

Although the etiology of eosinophilic cholecystitis is still obscure, the postulated causes include allergies, parasites, hypereosinophilic syndrome, and eosinophilic gastroenteritis. It is sometimes accompanied by several complications, but a simultaneous onset with pericarditis is very rares. A 28-year-old woman complained of acute right hypocondrial pain and dyspnea associated with systemic eruption. Several imaging modalities revealed acute cholecystitis and pericarditis with massive pericardial effusion. A marked peripheral blood eosinophilia was observed, and the eruption was diagnosed as urticaria. Her serum had a high titer of antibody against Ascaris lumbricoides . Treatment with albendazole drastically improved all clinical manifestations along with normalization of the imaging features and eosinophilia. We report herein a rare case of simultaneous onset of acute cholecystitis and pericarditis associated with a marked eosinophilia caused by parasitic infection.

Segregation of voiced and unvoiced components from residual of speech signal

In conventional source-filter models, voiced and unvoiced components were considered independently. However, in practice it was difficult to separate the source into two parts. An actual source consists of a mixture of two sources and the ratio varies according to the content or the intention of speaker. It had been investigated to separate the voiced and unvoiced components for different source models. Source signals were modeled based on the residual signal measured from inverse filtering. Three different source models were assumed. The parameters of each model were optimized for the original speech signal using a genetic algorithm. The resulting parameters were compared in terms of the mel-cepstral distance to the original signal, the spectrogram and the spectral envelope from the synthesized signal. The optimization method achieves an improvement of 15% for the Klatt model, but there is little improvement in the modified residual case.

New Process for Extracting Oil and Starch from Tea Seeds

A new process for extracting oil and starch from tea seed was introduced. The new process included one special link compared with all of the processes used now for tea seed oil and starch production. The link was static fermentation by which oil bodies and starch were separated naturally from tea seeds. By the process, tea seed oil and starch which were in conformity with government standards about edible oil and starch were successfully produced with 16% and 8% of production rate, respectively. The new process has many advantages, such as more simple equipments, lower production cost and whole natural products, etc..

Numerical study on freezing-thawing phase change heat transfer in biological tissue embedded with two cryoprobes

A two-dimensional model for freezing and thawing phase change heat transfer in biological tissue embedded with two cryoprobes was established.In this model,the blood vessels were considered as tree-like branched fractal network,and the effective flow rate and effective thermal conductivity of blood were obtained by fractal method.The temperature distribution and ice crystal growth process in biological tissue embedded with two cryoprobes during freezing-thawing process were numerically simulated.The results show that the growth velocity of ice crystal in freezing process from 200 to 400 s is more rapid than that from 400 to 600 s. Thawing process of frozen tissue occurs in the regions around cryoprobes tips and tissue boundary simultaneously,and the phase interfaces are close to each other until ice crystal melts completely.The distance of two cryoprobes has a more profound effect on the temperature distribution in freezing process at 400 s than at 800 s.

Hydrodynamics and Mass Transfer of Jet Co-flow Packing Tray

The jet co-flow packing tray(JCPT) with three different types of perforation in equal opening fraction was tested in two rectangular columns with 0.12m in width and 0.27m in length operated with air-water system. The influences of gas phase orifice F-factor and clear liquid height Hc on the amount of liquid lifted, Q, were examined. The corresponding correlation between Q with F-factor and equivalent diameter of perforated holes as well as Hc was obtained. Furthermore, the non-steady state mass transfer performance of JCPT was tested by the humidification of air with water. Finally, by the analysis of data and comparison, it was found that the JCPT tray with single cap and two holes exhibited the highest mass transfer efficiency and best performance.

Effect of Modified Atmosphere Packaging on Postharvest Quality of Rambutan cv. Binjai

An experiment on retail film packaging system was conducted to compare the atmospheric composition within sealed packs containing rambutan fruits. This research was done in order to study the effect of packaging films with different permeability on the some of physicochemical properties of rambutan during storage at 10℃. The films used were 0.090 mm low density polyethylene （LDPE）, 0.040 mm polyprophylene and 0.057 mm LDPE compared unwrapped fruits. Fruits were evaluated every 5 days for changes in moisture content, total sugars, vitamin C, hardness and color. Unwrapped rambutan had severe browning after 10 days. Sealed packages especially the LDPE had delayed the development of the browning for 20 days of storage and had the lowest weight loss.

Use of Residual Material in Biobanking： Solidarity, Common Good, and Informed Consent

Biological residual materials can be obtained from surgical activities or from pathological waste material collected for analysis and stored in formalin. This material can be stored in biobanks with the purpose of future research. Formalin-fixed tissue and also formalin-fixed paraffin embedded tissues are not suitable for all kinds of genetic studies on DNA or RNA, as formalin solution is well known for damaging nucleic acids. Therefore, for the purpose of conducting genetic studies, samples should be frozen in order to maintain a good quality of DNA/RNA over time Biobanks, in which waste samples are frozen, are undoubtedly expensive to maintain; however, it could be useful and important to consider their possible implication in particular research, regarding for example the tumor cells growth process, or when the procurement of samples is difficult. Regarding the relationship between informed consent and tissue collection, storage and research, two choices are possible： irreversible or reversible sample anonymization. These procedures involve different approaches and possible solutions that we will seek to define. Also, an important ethical aspect in regard to the role of biobanks is encouraging sample donation. For donors, seeing human sample being kept rather than discarded and seeing them become useful for research highlight the importance of the human body and improve the attitude towards donation. This process might also facilitate the giving of informed consent more trustfully and willingly.

The Efficiency of Non-repayable Funding Against Crisis Effects in Romania

The current economical crisis pointed out the gaps and the weak development of the Romanian economical system. If we were to compare the economy of a country to the human body then we would realize that constant and massive loss of ＂blood＂ may eventually lead to collapse of the economical system, which require Romania to speed up financial ＂transfusions＂. In these conditions, the most accessible and inexpensive source of funding is the non-repayable funding that Romanian economy can acquire by the year of 2013. In this paper we analyze the evolution of non-repayable funds allocated to Romania, in terms of those funds for the approved projects （their implementation has not yet started） but also in terms of those contracted projects or in the process of running （in fact representing ＂the necessary＂ amount of money that the Romanian economy needs）. The first part of the paper contains an overview of the situation about the requiring and the absorption of non-repayable funding since 2007 （officially since the crisis emerged in the U.S.） to present, also making an analysis of the influence they had on the Romanian economy. We take into account in this analysis that the effects of the crisis in Romania began to be felt in the second half of 2008, economical politics against crisis were not taken into accounted by this date. In this analysis we started from the assumption that one anti-crisis policy, taken into account by public decision members in Romania, is to increase efficiency and absorption of funds by raising the capacity of the Romanian economical environment for the implementation （and not only the winning ） of these funds. The second part of the paper contains an econometrieal development model which highlights the influence of changing the interest rates and exchange rate on the rate of contracting projects during January 2007-March 2010. The Analysis of the results emphasizes the stronger influence of the changing rate on the approved contracting projects compared with the changing influence of the reference interest rate. Following the results of the analysis we highlight the main reasons for which this economical policy of attracting and using outstanding funding represents until now, a failure more than a success. Also we present these several solutions to increase the volume of financial ＂transfusion＂ with a direct impact on the Romanian economy, arguing that such measures cannot be implemented without real political will from decision-makers in Romania.

Measurement of Economic Result in Public Organizations： A Departmental Analysis

The aim of this work is to demonstrate how public university hospital （UH） managers can improve the process of decision-making by using the measurement of economic value added to the society （EVAS） generated by these organizations. Thus, the economic values of the organization and its departments were calculated, according to the theory studied： measurement model of economic result of Slomski （1996）. It was considered the conduction of a case study in a public UH, evaluating its economic performance in a 3-year period. For the interpretation of results, the Data Envelopment Analysis （DEA） which categorized the departments of the hospital studied as efficient or inefficient was used. This study revealed that managers can improve the decision-making process by using the EVAS, since it has been established that this measurement of economic value has sensitivity to identify which of the economic value drivers should be emphasized in the management.

加固Linux系统的安全防线(上) 浅谈基于netfilter/iptables的软件防火墙

在网络安全措施中,防火墙是最基本的也是最关键安全防护措施。在浪潮的某些服务器产品,存储产品中都已经用到了该项技术。在新一代存储系统中,将会加入优化的软件防火墙,这将有力的加固存储服务系统的安全防线。

Apolipoprotein C1 regulates epiboly during gastrulation in zebrafish

Apolipoprotein C1 （Apocl） is associated with lipoprotein metabolism, but its physiological role during embryogenesis is largely unknown. We reveal a new function of Apoclb, a transcript isoform of Apocl, in epiboly during zebrafish gastrulation. Apoclb is expressed in yolk syncytial layers and in deep cells of the ventral and lateral region of the embryos. It displays a ra- dial gradient with high levels in the interior layer and low levels in the superficial layer. Knockdown of Apoclb by injecting antisense morpholino （MO） caused the epiboly arrest in deep cells. Moreover, we show that the radial intercalation and the ra- dial gradient distribution of E-cadherin are disrupted both in Apoclb knockdown and overexpressed embryos. Therefore, Apoc 1 b controls epiboly via E-cadherin-mediated radial intercalation in a gradient-dependent manner.