基于GCL算法的智能电网假数据攻击定位方法

针对假数据攻击行为的定位准确度较低,影响智能电网稳定运行能力的问题,提出基于GCL算法的智能电网假数据攻击定位方法。根据偏差系数求解结果,根据假数据的透明度水平定义CL算法模型;计算电网假数据样本的先验阈值指标,构建假数据攻击行为定位模型;按照电网区域划分原则,分析假数据攻击行为的隐蔽性,判定电网假数据隐蔽性攻击行为能力强度;计算假数据样本的识别特征,完善自适应定位标准,判断已存储数据参量,实现基于GCL算法的假数据攻击定位方法的设计。实验结果表明,该定位方法找到母线扰动事件中的假数据分别在位置S1、S2、S3、S4、S5,线路扰动事件当中的假数据分别在位置S6、S7,定位结果与实际情况一致,准确度较高,可以为电网运行提供技术支持。

GCL膨润土衬垫膨胀量对渗透性能的影响

GCL膨润土衬垫有很好的吸水膨胀性能,作为防渗材料被广泛应用在环境工程和水利工程。在上覆荷载作用下,GCL膨润土衬垫的膨胀量会受到影响。采用膨胀试验和渗透试验研究上覆荷载与膨胀量之间的关系,以及膨胀量对渗透系数的影响。结果表明,随着上覆荷载的增加,GCL膨润土衬垫膨胀量明显减小,荷载超过1000 kPa后几乎不会发生膨胀现象。GCL膨润土衬垫膨胀量大,防渗性能低,膨胀量达到12 mm时渗透系数增大1个数量级。根据拟合得到的膨胀量与上覆荷载、膨胀量与渗透系数的关系式,计算了不同堆载高度下的膨胀量和渗透系数,GCL膨润土衬垫上部铺设0.2 m的砂土,能大大提高安全性。

Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner

This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition(CVD)that has tungsten as its inner liner.The feasibility of this design was evaluated through penetration tests.Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners.The microstructures of the tungsten layers were analyzed using a scanning electron microscope(SEM).The feasibility analysis was carried out by pulsed X-rays,slug-retrieval test and static penetration tests.The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method.The results showed that the double-layer liners could form well-shaped jets.The errors between the X-ray test results and the numerical results were within 11.07%.A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug.Compared with the traditional pure copper shaped charge jet,the penetration depth of the double-layer shaped charge liner increased by 11.4% and>10.8% respectively.In summary,the test results are good,and the numerical simulation is in good agreement with the test,which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner.

Simulation Study of Solid Rocket Motor C/C Throat Liner Ablation Based on Two Regions

Based on the ablation micro-morphological characteristics, thermo-chemical ablation mechanism, and mechanical stripping mechanism, a dual-region solid rocket motor C/C throat liner ablation model and physical model are established. The ablation program was written and the experimental data of 70 lb BATES engine platform was used for model validation. The relative errors between the simulation calculation results and the experimental results were −6.83% - 10.20%. The ablation program was applied to study the effects of combustion chamber temperature, pressure, oxidation component concentration, throat particle concentration and particle scouring angle on the nozzle throat liner, which provides a reference for the design of the nozzle throat liner and the estimation of solid rocket motor ablation.

赤泥渗滤液对GCL多尺度孔隙结构及防渗性能影响

赤泥渗滤液会对赤泥堆场使用的土工合成黏土衬垫(Geosynthetic Clay Liner, GCL)防渗性能造成负面影响,易产生渗滤液渗漏风险,严重威胁地下水和土壤环境安全。为了从多尺度孔隙结构角度揭示GCL对赤泥渗滤液的防渗机理,通过柔性壁渗透试验获取GCL对赤泥渗滤液的渗透系数,利用XRD试验分析蒙脱石晶体结构和质量分数的变化,描述固液相互作用,并开展压汞试验和氮气吸附-脱附试验,定量探究渗透液体对GCL中膨润土多尺度孔隙结构的影响。结果显示,具有高离子强度的赤泥渗滤液可以压缩GCL中膨润土的扩散双电层厚度,抑制渗透膨胀过程,进而导致作为渗流通道的集合体内和集合体间孔隙(渗流孔隙)体积增大,GCL渗透系数大幅增加;强碱性的赤泥渗滤液能溶解具有吸水膨胀性的蒙脱石,生成非膨胀性的次生矿物。通过降低膨润土膨胀性能和堵塞孔隙作用可改变膨润土多尺度孔隙结构,进而影响GCL渗透系数。天然钠基GCL的防渗性能好于人工钠化GCL,这是因为前者蒙脱石质量分数较高,具有更好的膨胀性能,相同赤泥渗滤液渗透后,天然钠基GCL依旧可以保持较小的渗流孔隙体积。具有更高离子强度和更强碱性的赤泥渗滤液会因剧烈的固液相互作用,导致渗透后的GCL具有较大的渗流孔隙体积和较高的渗透系数。

GCL用于路基水分场调控可行性及铺设位置优化分析

为优化路基土水分场的调控铺设,基于水分场在路基中的迁移规律,对土工复合膨润土垫(GCL)在路基中调控水分场的影响因素进行了系统性研究。通过室内模型试验验证了GCL阻隔毛细水上升和防止雨水下渗的性能;基于水分在非饱和土路基中的迁移规律,采用数值模拟方法对GCL在路基中的铺设位置进行了优化;运用有限元分析法对比研究了现场尺度下GCL在路基中的铺设深度及铺设层数对路基水分场的影响。结果表明:GCL具有十分重要的防渗作用;在单层铺设条件下,GCL位于地面以下1.0 m处可以起到较好的调控水分场作用,GCL上、下0.3 m范围内路基土的体积含水量可以快速达到稳定状态和低值;GCL双层铺设的效果与单层铺设差异不大。

GCL复合垂直防渗墙中污染物运移的一维解析解

为研究膨润土防水毯(GCL)和水泥-膨润土防渗墙组成的新型复合垂直防渗墙中有机污染物的运移机理,分别考虑水泥-膨润土防渗墙和GCL作用,以及污染物击穿GCL复合垂直防渗墙迁移到零浓度的潜水层中,建立了污染物在GCL复合垂直防渗墙中的一维运移模型,并给出了出口边界采用混合边界条件时的一维解析解,所得结果与GeoStudio软件数值模拟结果高度吻合,由此验证了解析解的正确性,进而采用一维解析解开展了参数分析。研究结果表明:GCL层可以进一步提高垂直防渗墙的防污效果;有机污染物的半衰期主要影响水泥-膨润土防渗墙中的浓度分布,水泥-膨润土防渗墙的墙厚与渗透系数对墙体内部的污染物浓度分布和出口边界的污染物通量的影响较大。

GO/HTPB composite liner for anti-migration of small molecules

Hydroxyl-terminated polybutadiene/toluene diisocyanate(HTPB/TDI)system is widely used in composite solid propellants.The migrations of plasticizers and water molecules from solid propellants and surrounding environment to the inhibitor have always been the important issues.This study focuses on the preparation,characterization and anti-migration behavior of graphene oxide(GO)/HTPB nanocomposite liner.The GO/HTPB(GH)composite liners affect the migration of small molecules through a tighter cross-linked structure and weakening function of small molecule adsorption.The anti-migration performance of the liner at different temperatures was analyzed,and the influence of the added amount of GO on the anti-migration performance and adhesion performance was also systematically studied.The overall performance of the liner is optimized when the amount of GO filler is 0.3 wt%.After adding 0.3 wt%GO,the concentration of dioctyl sebacate(DOS)migrated into the liner is decreased by 23.28%,and the concentration of water molecules is decreased by 51.89%,indicating that the introduction of GO can significantly improve the anti-migration performance of the liner.In addition,the bond strength is greatly increased from 0.25 MPa to 0.95 MPa,which meets the application requirements of the current propellant system.This research provides an important way for the preparation of structure-function synergistic anti-migration composite liners.

土工膜GCL复合衬里剪切强度确定方法

为了完善和优化含土工膜(GM)和土工膨润土防水毯(GCL)组成的复合衬里边坡工程的稳定性分析方法,在对已有剪切试验结果进行综合分析的基础上提出了一种GM+GCL复合衬里剪切强度的简便确定方法。通过归纳GM+GCL复合衬里在涵盖低到高法向压力条件下的剪切破坏模式、峰值剪切强度特征和残余剪切强度特征,提出了将复合衬里作为一个复合界面整体看待时的剪切强度选取原则。考虑GM+GCL复合衬里的破坏面转移特征和峰值后软化特征,给出了具体的复合衬里峰值强度和残余强度简便确定方法。研究结果发展了含土工合成材料边坡的剪切强度计算办法,能够在实现快速分析工程安全的同时减小或避免开展GM+GCL复合衬里剪切试验所需的大量时间和精力。

The Efect of Rich Synthetic Copper-rich Solution on Antiseepage Dense Pre-hydration Geosynthetic Clay Liner

Dense pre-hydrated geosynthetic clay liners(DPH GCLs)were manufactured as innovative materials accompanied by the advantage of lower hydraulic conductivity(k).The k of DPH GCLs permeated with de-ionized water(DIW)was 9.8×10^(−12) m/s.The effect of Cu^(2+)synthetic solution on DPH GCLs was discussed.Furthermore,the effect mechanism was studied on the basis of test technologies.A significant adverse impact on hydraulic performance of DPH GCLs is found when the concentration of Cu^(2+)is greater than 1 g/L.SEM,XRD,XRF,FTIR,and XPS analyses show that the effect of Cu^(2+)on DPH GCLs includes two steps.Firstly,Cu^(2+)interacts with hydrophobic organic matter(HOM),and the adhesion of bentonite is destroyed,and some holes appear.The Cu^(2+)contacts with bentonite directly,and Cu^(2+)interacts with bentonite through ion exchange.Passivated phenomenon occurs on the surface of the bentonite,and swelling ability of bentonite is reduced,which causes permeable DPH GCLs.

Structural design of the fluted shaped charge liner using multi-section optimization method

Spin effect of the small diameter shaped charge results in the centrifugal stress during the jet stretching process. Consequently, the jet scatters, which deceases the jet penetration capability. In the present study, a multi-section method was proposed to design the spin-compensation liner. The spincompensation rate(SCR) of the liner was defined as the specific angular velocity that a fluted liner can offset. Based on the plain stress theory, SPH numerical method was applied to study the converging process of the 2D fluted structure. The spin-compensation mechanism of the fluted structure was illustrated. Then, nine cross sections were chosen along the liner axis equidistantly. On each of the section, a 2D fluted structure was designed to offset a given initial angular velocity. After, the optimized fluted structures were integrated into a 3D fluted liner. Jet appearances of the normal liner and the fluted liners under different initial angular velocities were compared, which verifies the practicality of the multi-sectional method. The multi-section optimization method provides a new efficient method of designing the shaped charge liner for a specific usage.

新型防渗材料钠基膨润土防水毯(GCL)在滹沱河生态修复三期工程(灵寿县)中的应用

钠基膨润土防水毯(GCL)作为新型防渗材料在水利工程中得到广泛应用。它具有整体稳定性好,抗变形强度高,施工操作简便,生态环保和永久防渗等性能,在滹沱河生态修复施工应用中收到了良好的防渗效果。此文阐述防水毯的防渗机理和施工工艺,并对施工应用中注意事项给予特别介绍,为今后防水毯的使用技术起到指导作用。

Viscoelastic Burger’s model for tunnels supported with tangentially yielding liner

This study proposed an analytical model for the tunnel supported with a tangentially yielding liner in viscoelastic ground.The efficiency of the developed analytical model was verified by comparing the calculated results with associated numerical simulation results.Using the analytical model,a comprehensive parameter sensitivity analysis was performed to examine the effects of the rate of tunnel face advancement,concrete liner thickness,installation time of liner,and strength and thickness of yielding elements on the tunnel responses.The results highlight the significant benefit of the tangentially yielding liner to relieve overstress in the tunnel liner and improve the stability of the tunnel.The yield efficiency of the tangentially yielding liner depends highly on the yielding strength and deformable capacity of the yielding elements and less on the installation time.

Parameter Study on a Composite Sound-Absorbing Structure Liner in Elevator Shafts

With the growing global environmental awareness,the development of renewable and green materials has gained increased worldwide interest to substitute conventional materials and are favorable for sustainable economic development.This paper proposed a novel eco-friendly sound absorbing structure(NSAS)liner for noise reduction in elevator shafts.The base layer integrated with the shaft walls is a damping gypsum mortarboard,and a rock wool board and a perforated cement mortarboard are used to compose the NSAS.Based on the acoustic impedance theory of porous materials and perforated panels,the sound absorption theory of the NSAS was proposed;the parameter effects of the rock wool board(flow resistivity,porosity,structure factor)and perforated panel(perforated rates,thickness,density,perforated diameter)on NSAS absorption were discussed theoretically for absorption improvement,and experiments were also conducted.Numerical results showed that the perforation rate,the thickness of the perforated plate,and the porosity,flow resistance,and volume density of the rock wool board played a key issue in the absorption performances of the NSAS.Experiments verified the accuracy of the proposed theoretical model.Wideband sound absorption performance of the NSAS at frequencies between 500–1600 Hz was achieved in both numerical analysis and experiments,and the sound absorption coefficient was improved to 0.72 around 1000 Hz after parameter adjustments.The NSAS proposed in this paper can also be made of other renewable materials with preferable structure strength and still has the potential to broaden the absorption bandwidth.It can provide a reference for controlling the elevator shaft noise.

压气储能地下储气库衬砌裂缝分布特征及演化规律研究

地下储气库衬砌的主要作用是将内压传递给围岩,且同时作为柔性密封层的附着基层。高内压作用下衬砌开裂可导致密封层出现反射型裂缝,进而引起高压气体的泄漏。为深入认识地下储气库衬砌的开裂特征,开发了基于FLAC3D平台的衬砌裂缝分析程序,研究了衬砌配筋方式、配筋率、钢筋保护层厚度、围岩类别和温压循环荷载作用等因素对衬砌开裂演化特征的影响。研究成果表明:对衬砌采取合理的配筋方式和改善围岩质量的措施可有效控制衬砌裂缝的宽度;采用分区配筋的方式可有效控制圆形断面隧洞式储气库衬砌中的最大裂缝宽度,同时降低衬砌的配筋量。空气压力和温度同步变化引起的热力耦合效应还有助于减小衬砌中出现的裂缝宽度。

大面积GCL膨润土防水毯施工技术研究与应用

在湿地公园建设过程中,因其特殊的地质条件及周边复杂的施工环境,如何做好防渗施工成为建设中面临的重要难题。本文以重庆市垫江县三合湖湿地公园项目为依托,提出了大面积GCL膨润土防水毯施工技术,通过对施工方案及工艺等不断优化及改进,保证了湿地公园大面积防渗效果。

药型罩形状对活性聚能侵彻体成型的影响

结合理论与数值模拟,对3种不同形状药型罩活性聚能侵彻体的成型行为开展了研究.数值模拟结果表明,在聚能效应下,球缺罩和大锥角圆锥罩形成尾部带有碎片云的类杆状活性聚能侵彻体,而小锥角圆锥罩则形成活性射流.相比于活性射流,类杆状活性聚能侵彻体速度较低,但凝聚性较好.进一步结合活性材料反应动力学方程,对活性聚能侵彻体成型激活反应行为进行分析.分析结果表明:活性射流激活区位于杵体外壁、射流头部和轴线附近;随炸高增加,激活区内活性材料反应不断加剧,特别是射流头部和轴线附近材料的反应,将导致活性射流膨胀发散,不利于侵彻;而类杆状活性聚能侵彻体激活区域主要集中在尾部碎片区和杆尾中心部位,化学反应对其影响相对较小.

锥形束CT评价人工耳蜗植入的电极深度和位置

目的分析人工耳蜗植入后电极植入深度、位置与耳蜗大小、盘旋方式的关系,探讨植入后电极深度的影响因素和电极移位的原因。方法选取植入CI24RE(CA)弯电极30例和SONATA ti100 Standard直电极人工耳蜗装置41例,利用锥形束CT测量术后电极植入长度、植入深度角、电极在耳蜗内的位置,分析上述指标与术前CT评估的耳蜗大小、倾斜角度的关系。结果①术后电极植入深度角和长度均存在较大的个体差异。直电极组平均植入深度角为702±53度,平均植入长度为30.02±1.29 mm;弯电极组平均植入深度角为441±45度,平均植入长度为18.4±1.0 mm,两组间差异有统计学意义(P<0.001)。②电极植入深度角与耳蜗底回的长径和宽径均呈负相关:直电极组r=-0.768(P<0.001)、r=-0.678(P<0.001),弯电极组r=-0.467(P=0.008)、r=-0.471(P=0.008)。电极植入长度与植入深度角呈正相关:直电极组r=0.578(P<0.001),弯电极组r=0.748(P<0.001)。③术后电极移位6例,均为弯电极且位于耳蜗180度位置。弯电极组中电极移位者与未移位者耳蜗底回倾斜角以及第一回和第二回之间的夹角差异有统计学意义(10.28度vs 8.75度,P=0.006;15.23度vs 14.00度,P=0.033)。结论人工耳蜗植入术后电极植入长度和深度角存在较大的个体差异,与耳蜗大小密切相关;耳蜗盘旋方式不同是引起电极移位的原因之一。

纤维缠绕塑料内胆表面处理装置的设计与分析

为提高目前塑料内胆的表面处理质量以及处理时间,节约时间和人工成本,本文针对纤维缠绕塑料内胆的表面处理设计了一套自动化的处理装置。它主要可以实现塑料内胆的自动夹持夹紧定位以及塑料内胆表面处理等功能。文中主要介绍了所设计的夹持传动装置以及等离子表面处理装置等相关结构,并在SolidWorks软件中对此套装置进行了总体设计与装配,在Workbench中对部分零部件进行了强度校核,分析Workbench中的相关结果。结果显示,该装置达到了相关力学要求且能够平稳传动,满足设计要求。

内燃机缸套穴蚀预测与抑制研究综述

内燃机缸套的剧烈振动会引起冷却液空化并造成穴蚀。缸套穴蚀问题一直是影响内燃机寿命和可靠性的难题之一,随着内燃机高热效率和轻量化设计要求的不断提高,缸套穴蚀问题受到越来越多的关注。实现缸套穴蚀的早期预测与抑制对清洁高效内燃机提高运行可靠性、降低开发和维护成本具有重要意义。介绍了缸套穴蚀的产生机理,总结了缸套振动的求解方法,综述了柴油机缸套穴蚀的预测与抑制研究现状。在此基础上,分别从试验和模型2个方面总结了缸套穴蚀风险的评估方法及各类方法的局限性。介绍了现有的缸套穴蚀抑制技术。论述了目前缸套穴蚀研究中存在的主要问题与挑战,并展望了未来的研究方向。