两种新的push-pull平衡的大数据量无线传感器网络数据分发算法

无线传感器网络中如何获得较低的通信代价同时在事件数据的push和pull之间实现更好的平衡是各种数据分发算法共同追求的目标.分析了目前已公认较好的两种典型的有结构和无结构的数据分发算法,指出了它们的优缺点.在此基础上,结合这两种算法使用的push-pull策略,针对不同应用环境下的无线传感器网络的ALL型查询的特定需求,提出了两种基于有结构和无结构存储模式相结合的混合型数据分发算法,分别是Hybrid-Dcs-Cn1(HDC1)算法和Hybrid-Dcs-Cn2(HDC2)算法.分析表明这两种算法在保证push-pull之间平衡的前提下解决了已有算法存在的热点问题:存储拷贝数多和查询性能低,能更好地适应传感器网络的特点,是两种能量高效的数据分发算法.

Push-Pull型pFLASH开关单元结构设计及特性

基于90 nm eFLASH工艺设计并制备了一种新型抗辐照Push-Pull型pFLASH开关单元,并对其特性进行了研究。该结构由2个2T-FLASH管（T1/T2）和1个信号传输PMOS管（T3）组成,采用带带隧穿（BTBT）编程方式和福勒-诺德海姆（FN）擦除方式实现其＂开/关＂态功能。同时,对其＂开/关＂态特性进行表征,研究其耐久性和电荷保持特性,最后,对其抗总剂量（TID）能力进行评估。实验结果表明：该器件的＂T1编程-T2擦除＂与＂T1擦除-T2编程＂态均可以实现信号传输管的＂开/关＂态功能,其阈值窗口的均值约为10.5 V;在工作电压为-1.2 V条件下,T3管的＂开＂态驱动电流均值约为0.92 mA,＂关＂态漏电流低于40 pA,且均表现出了良好的一致性。同时,该器件的循环擦/写次数可达10 000次,在25℃的＂开/关＂态应力条件下寿命大于10年,抗总剂量能力可达150 krad（Si）以上。

基于第三方的Push-Pull逆向物流模式

首先阐述了逆向物流的内涵、功能以及基于第三方逆向物流的提出,其次分析了外包逆向物流的优势,最后分析了生产控制系统中的Push-Pull方法.在此基础上,提出基于第三方的Push-Pull逆向物流模式.

基于DTN网络的PUSH-PULL策略研究

DTN网络是新一代的网络体系结构,PUSH-PULL是解决DTN网络中拥塞控制的一种有效策略,介绍了DTN网络中拥塞控制的研究现状,并对PUSH-PULL的各个策略进行了阐述,通过NS2搭建DTN网络环境并通过模拟对PUSH-PULL的7种策略进行仿真,模拟仿真结果表明,采用PUSH-PULL策略的可以有效的提高信息的传输率.

高并发数据共享系统基于Push-Pull混合模式的性能优化

随着面向服务架构的大规模分布式系统的应用,多个系统之间由于数据集成的需要,彼此间要高并发传递大量数据,特别是状态数据的同步,对数据的实时性要求越来越高。数据单纯通过客户端以Pull(拉取)模式获取已经不能满足实时性要求,高频率服务调用也会给服务端数据库带来较大的压力。单纯通过服务端以Push(推送)模式推送给客户端也不能满足客户端对个性化数据的需求,大量推送既会给服务端带来较大压力,又会造成客户端数据处理不及时。本文针对高并发数据共享系统应用过程中产生的性能问题,提出一种基于pub/sub消息处理的Push-Pull混合模式优化方案,实践表明该方案极大地提高了系统可用性及数据安全性,对同类系统的性能优化具有较好的借鉴作用。

Research into Technology of Bao Steel's Pickling Tension Leveler

According to the survey of Bao Steel's pickling tenstion leveler,the technology of the tension leveler is analysed systematically.In order to solve the problem which hinders the production,the given technological parameters of this leveler have been improved and good results achieved.

Push-Pull型不对称钴(III)咔咯的合成与性质

酸催化下,在水-甲醇体系中,合成并分离了3种含有Push-Pull取代基的新型低对称A2B型钴(III)咔咯,其结构经1H NMR,19F NMR和HR-MS(ESI-TOF)表征。并利用光谱学和电化学方法对3种钴咔咯的电子结构进行了深入研究。结果表明:引入Push-Pull型不对称对钴(III)咔咯分子的电子结构有明显的调控作用,且随着引入基团的改变而产生显著的规律性差异,为进一步的分子设计、合成及其应用奠定基础。

Exploiting push-pull strategy to combat the tea green leafhopper based on volatiles of Lavandula angustifolia and Flemingia macrophylla

Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppers/trap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppers/trap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppers/trap/day. Control efficacy on the leafhoppers within the push-pull zones increased progressively from day 1(43%) to day 5(73%). This push-pull approach might have a great potential as a green control strategy for combating the tea green leafhoppers.

Two-stage treatment process of pickling wastewater in the cold-rolling production of stainless steel

Based on the characteristics of pickling wastewater in the cold-rolling production of stainless steel, a new processing route, featuring source sludge reduction, wastewater two-stage treatment, heavy metal-contained sludge and calcium salt sludge separating recovery, was proposed. As shown by the research results, after the two-stage process treatment, the effluent water can steadily reach the emission standards, the sludge yield can be decreased by more than 8% ; within the heavy metal-contained sludge, the recovery rates of Fc,Cr and Ni can either reach or surpass 95% ,and the total content ofF and S can drop to around 3%. Therefore,the sludge in the front part can be used as ferric dust. In the calcium salt sludge ,the recovery rate of F can either reach or surpass 85% ,and the total contents of Fe,Cr and Ni can fall below 0.5%. So the sludge in the rear part can be used as fluorgypsum or fluorite. Meanwhile,the results of the analysis on heavy metals leaching toxicity and morphologic distribution indicate that the two kinds of sectionalized sludge are not classified as hazardous wastes, which have a stable behavior and better utilization values compared with the former mixed- sludge.

Synthesis of Fe_3O_4 Magnetic Powder from Spent Pickling Liquors

Spent pickling liquors pose a serious environmental problem in most industrialized countries, mainly owing to their corrosive properties and their ferrous iron and hydrochloric acid content. In this paper, spent pickling liquor was used as an inexpensive raw material to prepare Fe304 magnetic powder via an oxidation method. Being able to recover the dissolved iron from spent pickling liquors would not only salvage a valuable material but also render the effluent environmentally benign. The structure of the Fe_3O_4 magnetic powder was characterized by X-ray diffraction. The morphology and size were characterized by scanning electron microscopy and transmission electron microscopy. Their magnetic properties were tested at room temperature by a vibrating sample magnetometer. In addition, the saturation magnetization of Fe_3 O_4 products can be further enhanced to 96.1 emu/g after purification.

Does acid pickling of Mg-Ca alloy enhance biomineralization?

The mechanical and physical properties of biodegradable magnesium(Mg)alloys make them suitable for temporary orthopaedic implants.The success of these alloys depends on their performance in the physiological environment.In the present work,surface modification of Mg-Ca binary alloy by acid pickling for better biomineralization and controlled biodegradation is explored.The corrosion rates of nitric and phosphoric acid treated samples were analysed by conducting electrochemical corrosion tests.In vitro degradation behaviour was studied using immersion test in simulated body fluid(SBF).The sample surfaces were characterized using scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).It is seen that acid pickling leads to significant improvement in biomineralization and develop in situ calcium phosphate(Ca P)coating on the sample surfaces.In addition,the treated samples recorded a reduced degradation rate in the SBF compared to untreated samples.Thus,acid pickling is suggested as an effective surface treatment method to tailor the biomineralization and degradation behaviour of the Mg-Ca alloy in the physiological environment.

Characterization and recycling of nickel- and chromium-contained pickling sludge generated in production of stainless steel

Pickling sludge generated during the neutralization of pickling wastewater with calcium hydroxide in stainless steel pickling process was characterized using X-ray fluorescence spectrometry,X-ray diffractometry,scanning electron microscopy,thermogravimetry and differential scanning calorimetry,etc.The major compositions of pickling sludge are CaF2,CaSO4,Me(OH)n(M: Fe,Cr,Ni),and the content of CaF2 is high in the sludge.The melting point of pickling sludge is about 1350 °C and the viscosity is about 0.14 Pa·s at 1450 °C,which are comparatively lower than those of normal refining slag.After heat treatment,the contents of sulfur and fluorine in the pickling sludge were reduced,confirming the thermal decomposition of sulfate in the sludge.Fluorine in the sludge is reduced by the gaseous SiF4 and AlF3 generated through the reactions of CaF2 with SiO2 and Al2O3.The preliminary results from the reduction test indicate that the sulfur content in the steel is not affected by the presence of sulfur in the sludge.The recovery of nickel is about 40%,and the chromium content changes marginally due to the protective atmosphere under the reduction condition of chromic oxide.The pickling sludge is a potential auxiliary material for the production of stainless steel.

One-step pickling-activation before magnesium alloy plating

A one-step pickling-activation process was proposed as an environmental friendly pretreatment method in phosphate-permanganate solution before electroplating on magnesium alloys. The effects of pickling-activation on qualities of coating were assessed by adhesion and porosity testing of copper plating. The interfacial reactions between specimen and solution were analyzed with SEM,EDX and XRD. The results show that the developed process of pickling-activation can equalize the potentials on substrate surface. The compacted zinc film can be obtained by zinc immersion after treating magnesium alloy in the pH 4-6 phosphate-permanganate solution for 3-5 min. The adhesion and corrosion resistance of copper plating are enhanced. The one-step pickling-activation can replace the existing two-step process of acid pickling and activation which contains a great deal of chromium and fluorine. The procedure of surface pretreatment is simplified and the production environment is improved.

Push-Pull Finite-Time Convergence Distributed Optimization Algorithm

With the widespread application of distributed systems, many problems need to be solved urgently. How to design distributed optimization strategies has become a research hotspot. This article focuses on the solution rate of the distributed convex optimization algorithm. Each agent in the network has its own convex cost function. We consider a gradient-based distributed method and use a push-pull gradient algorithm to minimize the total cost function. Inspired by the current multi-agent consensus cooperation protocol for distributed convex optimization algorithm, a distributed convex optimization algorithm with finite time convergence is proposed and studied. In the end, based on a fixed undirected distributed network topology, a fast convergent distributed cooperative learning method based on a linear parameterized neural network is proposed, which is different from the existing distributed convex optimization algorithms that can achieve exponential convergence. The algorithm can achieve finite-time convergence. The convergence of the algorithm can be guaranteed by the Lyapunov method. The corresponding simulation examples also show the effectiveness of the algorithm intuitively. Compared with other algorithms, this algorithm is competitive.

Acid-pickling plates and strips speed control system by microwave heating based on self-adaptive fuzzy PID algorithm

Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful in overcoming non-linear dynamic behavior, uncertain and time-varying parameters, un-modeled dynamics, and couples between the automatic turbulence control (ATC) and the automatic acid temperature control (AATC) with varying parameters during the operation process. The quasi-cascade control system of inner and outer loop self-adaptive fuzzy PID controller was built, which could effectively control the pickling speed of plates and strips. The simulated results and real application indicate that the plates and strips acid pickling speed control system has good performances of adaptively tracking the parameter variations and anti-disturbances, which ensures the match of acid pickling temperature and turbulence of flowing with acid pickling speed, improving the surface quality of plates and strips acid pickling, and energy efficiency.

Study on the simulated pickling of 443NT medium chrome ferritic stainless steel

The oxide scale structure of 443NT hot-rolled strips was analyzed. The pickling of 443NT stainless steel was simulated via the 6σ experimental design. The results indicate that parabolic relations exist between the pickling scores and some of the pickling influencing factors, such as the nitric acid density, the hydrofluoric acid density and the pickling temperature. Effective pickling of 443NT can be achieved by controlling the pickling processing parameters with the HNO3 density ranging from 80 g/L to 180 g/L ,the HF density from 20 g/L to 40 g/L and the pickling temperature from 45 ℃ to60 ℃.

Mechanism underlying the formation of cloud-shaped defects in 304 stainless steel after hot-rolled annealing and pickling

It is highly imperative to understand the mechanism underlying the formation of cloud-shaped defects in stainless steel to reduce the defect incidences. This study investigated the defect microstructure by SEM, simulated pickling in the laboratory, and performed structure analysis of oxide scales after hot rolling. Results show that the cloud-shaped defects in 304 No. 1 surface （after hot-rolled annealing and pickling） cause the pickling chromatic aberration between the honeycomb-shaped grains of the Cr-depleted layer and the smooth grains of the stainless steel matrix, which is formed in the case of insufficient pickling. The chromatic aberration is related to the uneven oxide scales formed before pickling. With the improvement of pickling capacity, it is possible to completely pickle the Cr-depleted layer and eliminate the cloud-shaped defects.

A new acid pickling process for copper alloys

The cleaning process of removing oxides on the surface of copper alloy sheetswas investigated systematically. Through optimizing, a perfect process was selected that is fit forremoving oxides on the surface. By acid pickling, all kinds of copper oxides are removedcompletely, furthermore, no poisonous gases are given out and a smooth and clean surface of copperalloys is obtained. At present, the process is applied successfully in the copper-processingindustry.

Analytical Method to Monitor Industrial Pickling Baths Initially Constituted by HF, HNO₃

The present study couples the acid/basis titration and the ICP analysis in order to monitor the concentrations of nitric and hydrofluoric acids, and presents into baths used to pickle alloys of titanium or stainless steel, largely employed in the aeronautic industry. The pickling of the alloys releases various metallic cations able to react with HF in order to lead to metal-fluoride complexes and free H+, the last being able to react with the basis. In this study, it was determined: the most significant correlations providing the number of the protons released by the complexation of the metallic cation by the fluoride. The proposed method based on: 1) these correlations;2) the titration pH = f(VKOH) curves;and 3) the content of metallic cations determined by ICP, enables the monitoring of the content of HNO3 and HF into the pickling bath. Assuming that one bath was used for one type of alloy (alloys of Titanium for example, or alloys of stainless steel), then the proposed method appears providing reliable concentration values of both acids as well as metallic cations.

Innovative surfactant of Gemini-type for dissolution mitigation of steel in pickling HCl medium

A new surfactant of Gemini-type,N,N'-((phthylbis(oxy))bis(ethane-2,1-diyl))bis(N,N-dimethyldodecan-1-aminium bromide)is prepped&confirmed.The dissolution suppression impact of the new compound on steel is performed in 1 mol·L^(-1)HCl environment by means of chemical and electrochemical methods.The prepared surfactant is an agreeable dissolution inhibitor for steel.The mitigation efficacy rises with the quantity of the compound.The surfactant belongs to inhibitors of mixed-type.The adsorption of the synthesized compound followed the Langmuir's model.The negative magnitudes of bothΔG_(ads)^(θ) andΔH^(adsθ)indicate that the adsorption process proceeds from its own accord and exothermic.The mechanism of adsorption is elucidated by scanning microscopy.It is established that the transfer resistance(R_(ct))value rose,where the value of the phase element(CPE)reduced with the amount of synthesized inhibitor.According to the experimental data arrived by surface tension measurements,the prepared compound is a powerful active agent at the air/water boundary.