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Metal extraction and recovery from cathode material of spent lithium-ion batteries utilizing an organic acid reagent scheme
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作者 WU Jia-jia KIM Jaeyeon +1 位作者 AHN Junmo LEE Jaeheon 《Journal of Central South University》 2025年第9期3645-3656,共12页
This study focuses on using a green reagent scheme of methanesulfonic acid (MSA) and citric acid (CA) to extract valuable metals from the cathodes, aiming to minimize environmental impact during the recycling process.... This study focuses on using a green reagent scheme of methanesulfonic acid (MSA) and citric acid (CA) to extract valuable metals from the cathodes, aiming to minimize environmental impact during the recycling process. Leaching studies on LiCoO_(2) identified optimal conditions as follows: 2.4 mol/L MSA, 1.6 mol/L CA, S/L ratio of 80 g/L, leaching temperature of 90oC and leaching time of 6 h. The maximum Co and Li extraction achieved was 92% and 85%, respectively. LiCoO_(2) dissolution in MSA-CA leaching solution is highly impacted by temperature;Avrami equation showed a good fitting for the leaching data. The experimental activation energy of Co and Li was 50.98 kJ/mol and 50.55 kJ/mol, respectively, indicating that it is a chemical reaction-controlled process. Furthermore, cobalt was efficiently recovered from the leachate using oxalic acid, achieving a precipitation efficiency of 99.91% and a high-purity cobalt oxalate product (99.85 wt.%). In the MSA-CA leaching solution, MSA served as a lixiviant, while CA played a key role in reducing Co in LiCoO_(2). The overall organic acid leaching methodology presents an attractive option due to its reduced environmental impact. 展开更多
关键词 methanesulfonic acid citric acid cathode material leaching organic acid reagent scheme
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S-scheme活性炭负载g-C_(3)N_(4)/TiO_(2)光催化混凝土降解性能分析
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作者 张典 《无机盐工业》 北大核心 2025年第4期118-127,共10页
为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素... 为了解决抗生素废水污染和室内装修低浓度甲醛污染,采用简易的混合高温煅烧法制备了活性炭负载g-C_(3)N_(4)/TiO_(2)(g-C_(3)N_(4)/TiO_(2)/AC)复合光催化剂。通过XRD、XPS、TEM、UV-vis DRS和PL等技术对复合光催化剂的物相晶型、元素组成、微观形貌、光谱响应范围和光生载流子重组等进行了表征。S-scheme异质结弯曲能带和内电场实现了光生载流子的高效分离,拓宽了光谱吸收范围,有效保留了高活性的·O_(2)^(-)、h^(+)和·OH等活性基团,表现出优异的磺胺甲基噻唑(STZ)降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC投加量为1.0 mg和STZ初始质量浓度为100 mg/L条件下,可见光照射30 min时STZ降解率为98.8%,明显优于g-C_(3)N_(4)、TiO_(2)和TiO_(2)/AC。g-C_(3)N_(4)/TiO_(2)/AC掺杂到环氧树脂涂料中合成了光催化涂料,通过空气喷枪均匀喷涂到混凝土表面得到光催化混凝土,光催化混凝土表现出良好的甲醛降解活性和稳定性,g-C_(3)N_(4)/TiO_(2)/AC负载量为3%、甲醛初始质量浓度为1000 mg/L、可见光照射180 min时,甲醛降解率达到了96.3%,有效实现了室内装修低浓度甲醛气体的高效降解。 展开更多
关键词 g-C_(3)N_(4) TiO_(2) 光催化 混凝土 S-scheme电荷转移机制 抗生素降解 室内装修甲醛降解
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Microwave-assisted preparation of Z scheme heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)for peroxymonosulfate activation towards levofloxacin degradation
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作者 HAN Peng-da DONG Guo-hua +6 位作者 ZHANG Xin-jia CHAI Dong-feng SU Ting ZHANG Zhuan-fang ZHAO Ming LI Jin-long ZHANG Wen-zhi 《Journal of Central South University》 2025年第3期894-918,共25页
It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)h... It is still challenging for exploring high-active photocatalysts to efficiently remove levofloxacin(LFX)by activating peroxymonosulfate(PMS).Herein,we constructed a novel Z scheme ZnFe_(2)O_(4)/g-C_(3)N_(4)/CQDs(ZCC)heterojunction by anchoring ZnFe_(2)O_(4)on tubular-like g-C_(3)N_(4)induced by CQDs(denoted as CNC)using microwave-assisted thermal methods.The ZCC exhibits the highest photocatalytic activity in activating PMS for LFX degradation,endowing a removal rate~95.3%,which is 4.8 and 7.3 times that of pure ZnFe_(2)O_(4)(19.8%)and g-C_(3)N_(4)(13.1%),separately.The enhanced photocatalytic activity of ZCC can be attributed to the distinctive morphology of CNC,enhanced light response,increased specific surface area and abundant pore structure.Besides,the formed Z scheme heterojunction and CQDs acting as a transmission bridge of the photogenerated charges(e−and h+)can accelerate transfer and inhibit recombination of e−and h+.Radical capture experiments and electron spin resonance(ESR)measurements revealed that SO4•-and O2•-play a predominant role in degradation process of LFX.Liquid chromatography-mass spectrometry(LC-MS)was applied to identify intermediates and propose feasible degradation pathways of LFX.In conclusion,this study presents a promising strategy for regulating the photocatalytic activity of g-C_(3)N_(4)by simultaneously integrating CQDs induction and Z scheme heterojunction construction. 展开更多
关键词 ZnFe_(2)O_(4) carbon quantum dots g-C_(3)N_(4) LEVOFLOXACIN Z scheme heterojunction
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Special secret sharing scheme with the function of assignment 被引量:3
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作者 叶振军 孟繁桢 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期651-653,共3页
A concept of secret sharing scheme with the function of assignment is proposed. It provides great capabilities for many practical applications. In this scheme, the dealer can randomly assign one or more than one parti... A concept of secret sharing scheme with the function of assignment is proposed. It provides great capabilities for many practical applications. In this scheme, the dealer can randomly assign one or more than one participant to get the secret at any time, but these participants can get nothing about the secret before that moment. At the same time, the other participants cannot get anything about the secret by stealing the secret value when it is transferred. However, if the dealer is lost, a certain number or more partidtmnts of them can reoonstruct the secret by ccoperating. In order to clear this concept, an illustrating scheme with geometry method and a practical scheme with algebra method is given. 展开更多
关键词 secret sharing THRESHOLD assignment scheme dynamtic assignment scheme.
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Application of ADER Scheme in MHD Simulation 被引量:1
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作者 ZHANG Yanyan FENG Xueshang +1 位作者 JIANG Chaowei ZHOU Yufen 《空间科学学报》 CAS CSCD 北大核心 2012年第2期170-181,共12页
The Arbitrary accuracy Derivatives Riemann problem method(ADER) scheme is a new high order numerical scheme based on the concept of finite volume integration,and it is very easy to be extended up to any order of space... The Arbitrary accuracy Derivatives Riemann problem method(ADER) scheme is a new high order numerical scheme based on the concept of finite volume integration,and it is very easy to be extended up to any order of space and time accuracy by using a Taylor time expansion at the cell interface position.So far the approach has been applied successfully to flow mechanics problems.Our objective here is to carry out the extension of multidimensional ADER schemes to multidimensional MHD systems of conservation laws by calculating several MHD problems in one and two dimensions: (ⅰ) Brio-Wu shock tube problem,(ⅱ) Dai-Woodward shock tube problem,(ⅲ) Orszag-Tang MHD vortex problem.The numerical results prove that the ADER scheme possesses the ability to solve MHD problem,remains high order accuracy both in space and time,keeps precise in capturing the shock.Meanwhile,the compared tests show that the ADER scheme can restrain the oscillation and obtain the high order non-oscillatory result. 展开更多
关键词 ADER scheme Generalized Riemann problem MHD numerical simulation HLL scheme
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APPLICATIONS OF HIGHER-ORDER UPWIND SCHEME FOR PROJECTILES IN TRANSONIC FLOW
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作者 鞠玉涛 郑亚 武晓松 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
针对弹丸跨音速粘性绕流流场进行了数值仿真研究,并与实验进行了对比。数值仿真的控制方程为雷诺平均的Navier-Stokes方程,湍流模型采用Baldwin-Lomax模型,应用了四阶的MUSCL TVD格式。结果表明,该方法可以取得高清晰度的流场结构。
关键词 TVD格式 NAVIER-STOKES方程 弹丸流动 APPLICATIONS OF HIGHER-ORDER UPWIND scheme FOR
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S-scheme ZnO/MoS_(2)异质结构筑与对盐酸四环素降解性能
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作者 胡怀生 张鹏会 《兰州理工大学学报》 CAS 北大核心 2022年第6期28-33,共6页
抗生素药物使用范围广且用量大,导致大量抗生素废水进入水体或者残留在土壤环境中,对人类健康造成威胁,然而传统工艺对其去除效果并不理想.以ZnO为基底,通过掺杂MoS_(2),制备了S-scheme ZnO/MoS_(2)异质结复合材料,研究了该材料对抗生... 抗生素药物使用范围广且用量大,导致大量抗生素废水进入水体或者残留在土壤环境中,对人类健康造成威胁,然而传统工艺对其去除效果并不理想.以ZnO为基底,通过掺杂MoS_(2),制备了S-scheme ZnO/MoS_(2)异质结复合材料,研究了该材料对抗生素废水的净化性能.通过调节复合材料中ZnO含量、光照条件、盐酸四环素浓度等,探讨了ZnO/MoS_(2)复合材料对不同浓度盐酸四环素(tetracycline hydrochloride,TC)废水的净化效果.结果表明:在光照条件下,催化剂复合比为1∶1的ZnO/MoS_(2)复合材料对60 mg·L^(-1)四环素废水的降解效率可达88%(pH=7,105 min);电子传递与污染物降解机理研究表明,电子由ZnO导带迁移至MoS_(2)价带,形成S-scheme异质结,从而有效提高了催化效率与污染物降解性能. 展开更多
关键词 ZNO MoS_(2) S-scheme异质结 盐酸四环素 废水净化
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Scheme语言的LED自由曲面透镜快速建模方法(英文) 被引量:1
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作者 戴艺丹 屈恩世 任立勇 《红外与激光工程》 EI CSCD 北大核心 2015年第9期2690-2695,共6页
传统的自由曲面透镜建模通常需要多个软件共同协作完成,其建模过程繁琐,且由于不同软件之间的不兼容会导致模型在导入光学仿真软件时出现微小形变。提出一种在光学仿真软件中利用Scheme语言直接进行快速建模的LED自由曲面透镜建模方法... 传统的自由曲面透镜建模通常需要多个软件共同协作完成,其建模过程繁琐,且由于不同软件之间的不兼容会导致模型在导入光学仿真软件时出现微小形变。提出一种在光学仿真软件中利用Scheme语言直接进行快速建模的LED自由曲面透镜建模方法。根据光源辐射特性和需要实现的照明面上的能量分布,采用划分网格法,利用Snell方程和能量守恒定律,沿经纬方向分别迭代求解,在得到自由曲面各节点坐标后,分别采用3D建模软件和Scheme语言编程构建透镜模型。通过光学仿真软件,模拟计算了100万条光线,直径1mm的光源在距离地面10 m、面积为40 m×10 m的照明区域内的照度分布。结果表明:利用Scheme语言在光学仿真软件中直接快速建模避免了模型从3D软件导入光学仿真软件时产生的微小形变从而使光照均匀度由67%提升到93.5%。同时Scheme语言编程建模仅需5 s,建模速度远高于3D建模软件。 展开更多
关键词 scheme语言 LED道路照明 快速建模 自由曲面透镜 二次光学设计
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将In_(2)O_(3)/CdSe-DETA纳米复合材料中的电荷转移从Type-Ⅰ转变为S-Scheme以提高光催化制氢的活性和稳定性 被引量:4
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作者 李真 刘雯 +3 位作者 陈春旭 马婷婷 张金锋 王正华 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第6期64-74,共11页
化石能源的问题限制了人类的发展。解决这个问题的有效方法是发展可持续性的清洁能源。近年来,氢气作为一种新型的清洁能源被争相报道。氢气燃烧热很大,且产物只有水,完全符合绿色环保可持续性能源的特点。因此,解决氢能源的生产方法就... 化石能源的问题限制了人类的发展。解决这个问题的有效方法是发展可持续性的清洁能源。近年来,氢气作为一种新型的清洁能源被争相报道。氢气燃烧热很大,且产物只有水,完全符合绿色环保可持续性能源的特点。因此,解决氢能源的生产方法就可以有效地解决能源危机问题。自TiO_(2)在1972年作为光催化剂分解水产生氢气开始,半导体光催化剂分解水产生氢气登上了历史的舞台。然而,单一组分光催化剂的固有缺点限制了它的实际应用,寻找克服单一组分光催化剂缺点的解决方案仍然具有挑战性。相对于单一的光催化剂,复合材料光催化剂可以更有效地分离光生电子和空穴,增加光催化析氢反应的速率。因此,通过选择复合材料异质结处合适的光催化机制(如:S-scheme),可以进一步提升催化剂的光催化析氢活性和稳定性。本文通过改变合成条件获得了一系列具有不同带隙宽度的单一CdSe-DETA光催化剂。光催化实验显示调节CdSe-DETA的带隙(2.31eV)可以获得最佳的光催化产氢活性,但是其稳定性很差。因此,我们将CdSe-DETA纳米花附着在In2O3多孔纳米片表面,构建了In_(2)O_(3)/CdSe-DETA纳米复合材料,以提升光催化析氢活性,稳定性和光电流响应。In_(2)O_(3)/CdSe-DETA纳米复合材料中异质结的类型可随着CdSe-DETA带隙宽度的改变而变化。随着CdSe-DETA带隙宽度的增加,异质结的类型可从Type-I型转变到S-scheme型。相对于单一光催化剂和Type-I型光催化剂,S-scheme型In_(2)O_(3)/CdSe-DETA纳米复合材料具有更高的光催化活性以及良好的稳定性。因此,我们选择S-scheme异质结的In_(2)O_(3)/CdSe-DETA纳米复合材料来获得光催化活性和稳定性的最大收益。此外,我们通过差分电荷密度计算结合实验结果证实了S-scheme异质结的存在。S-scheme异质结In_(2)O_(3)/CdSe-DETA纳米复合材料有效分离了光生电子和空穴,最大程度地利用复合材料的导带和价带,高效且稳定的光催化析氢。本研究展示了一种调制载流子转移机制的策略,可为开发高效的析氢光催化剂提供借鉴。 展开更多
关键词 带隙 S-scheme 理论计算 析氢 光腐蚀
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S-scheme光催化剂在制氢、还原CO_(2)及降解污染物领域的研究进展 被引量:1
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作者 王禹程 蔡天凤 +3 位作者 赵华 李会鹏 马骏 刘源 《石油化工》 CAS CSCD 北大核心 2022年第10期1242-1248,共7页
简要阐述了S-scheme光催化剂的反应机理,综述了多种由不同材料构建而成的S-scheme光催化剂在光分解水制氢、CO_(2)还原及污染物降解等领域的应用研究进展,简要分析了S-scheme光催化剂光催化效率高的主要原因,并对S-scheme光催化剂未来... 简要阐述了S-scheme光催化剂的反应机理,综述了多种由不同材料构建而成的S-scheme光催化剂在光分解水制氢、CO_(2)还原及污染物降解等领域的应用研究进展,简要分析了S-scheme光催化剂光催化效率高的主要原因,并对S-scheme光催化剂未来研究方向与应用前景进行了展望。 展开更多
关键词 S-scheme光催化剂 制氢 二氧化碳还原 污染物降解
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石墨相氮化碳基Z-Scheme体系光催化分解水研究进展 被引量:2
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作者 时晓羽 李会鹏 +1 位作者 赵华 张杰 《石油化工》 CAS CSCD 北大核心 2019年第9期982-987,共6页
石墨相氮化碳(g-C3N4)以独特的电子结构、稳定的化学结构和显著的可见光活性而备受瞩目,g-C3N4基Z-Scheme光催化体系能够有效地降低光生电子空穴的复合几率,提高光源吸收利用率。介绍了光催化分解水的反应机理,综述了g-C3N4基Z-Scheme... 石墨相氮化碳(g-C3N4)以独特的电子结构、稳定的化学结构和显著的可见光活性而备受瞩目,g-C3N4基Z-Scheme光催化体系能够有效地降低光生电子空穴的复合几率,提高光源吸收利用率。介绍了光催化分解水的反应机理,综述了g-C3N4基Z-Scheme体系在光催化水氧化、光催化水解制氢、光催化全分解水方面的应用,并对未来Z-Scheme的发展进行了展望。 展开更多
关键词 石墨相氮化碳 Z-scheme 光催化体系 光催化分解水
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SCHEMES OF GAS PRODUCTION FROM NATURAL GAS HYDRATES 被引量:6
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作者 李淑霞 陈月明 杜庆军 《化工学报》 EI CAS CSCD 北大核心 2003年第z1期102-107,共6页
Natural gas hydrates are a kind of nonpolluting and high quality energy resources for future, the reserves of which are about twice of the carbon of the current fossil energy (petroleum, natural gas and coal) on the e... Natural gas hydrates are a kind of nonpolluting and high quality energy resources for future, the reserves of which are about twice of the carbon of the current fossil energy (petroleum, natural gas and coal) on the earth. And it will be the most important energy for the 21st century. The energy balance and numerical simulation are applied to study the schemes of the natural gas hydrates production in this paper,and it is considered that both depressurization and thermal stimulation are effective methods for exploiting natural gas hydrates, and that the gas production of the thermal stimulation is higher than that of the depressurization. But thermal stimulation is non-economic because it requires large amounts of energy.Therefore the combination of the two methods is a preferable method for the current development of the natural gas hydrates. The main factors which influence the production of natural gas hydrates are: the temperature of injected water, the injection rate, the initial saturation of the hydrates and the initial temperature of the reservoir which is the most important factor. 展开更多
关键词 NATURAL GAS hydrate energy balance NUMERICAL simulation scheme of production
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An improved computation scheme of strapdown inertial navigation system using rotation technique 被引量:8
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作者 张伦东 练军想 +1 位作者 吴美平 胡小平 《Journal of Central South University》 SCIE EI CAS 2012年第5期1258-1266,共9页
To improve the accuracy of strapdown inertial navigation system(SINS) for long term applications,the rotation technique is employed to modulate the errors of the inertial sensors into periodically varied signals,and,a... To improve the accuracy of strapdown inertial navigation system(SINS) for long term applications,the rotation technique is employed to modulate the errors of the inertial sensors into periodically varied signals,and,as a result,to suppress the divergence of SINS errors.However,the errors of rotation platform will be introduced into SINS and might affect the final navigation accuracy.Considering the disadvantages of the conventional navigation computation scheme,an improved computation scheme of the SINS using rotation technique is proposed which can reduce the effects of the rotation platform errors.And,the error characteristics of the SINS with this navigation computation scheme are analyzed.Theoretical analysis,simulations and real test results show that the proposed navigation computation scheme outperforms the conventional navigation computation scheme,meanwhile reduces the requirement to the measurement accuracy of rotation angles. 展开更多
关键词 strapdown inertial navigation system rotation technique navigation computation scheme error characteristic
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Numerical prediction of inner turbulent flow in conical diffuser by using a new five-point scheme and DLR k-ε turbulence model 被引量:2
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作者 蒋光彪 何永森 +1 位作者 舒适 肖映雄 《Journal of Central South University》 SCIE EI CAS 2008年第S1期181-186,共6页
The internal turbulent flow in conical diffuser is a very complicated adverse pressure gradient flow.DLR k-ε turbulence model was adopted to study it.The every terms of the Laplace operator in DLR k-ε turbulence mod... The internal turbulent flow in conical diffuser is a very complicated adverse pressure gradient flow.DLR k-ε turbulence model was adopted to study it.The every terms of the Laplace operator in DLR k-ε turbulence model and pressure Poisson equation were discretized by upwind difference scheme.A new full implicit difference scheme of 5-point was constructed by using finite volume method and finite difference method.A large sparse matrix with five diagonals was formed and was stored by three arrays of one dimension in a compressed mode.General iterative methods do not work wel1 with large sparse matrix.With algebraic multigrid method(AMG),linear algebraic system of equations was solved and the precision was set at 10-6.The computation results were compared with the experimental results.The results show that the computation results have a good agreement with the experiment data.The precision of computational results and numerical simulation efficiency are greatly improved. 展开更多
关键词 conical DIFFUSER turbulent flow DLR k-ε turbulence model 5-point scheme ALGEBRAIC MULTIGRID method(AMG)
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A sink moving scheme based on local residual energy of nodes in wireless sensor networks 被引量:4
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作者 谭长庚 许可 +1 位作者 王建新 陈松乔 《Journal of Central South University》 SCIE EI CAS 2009年第2期265-268,共4页
In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving ... In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly. 展开更多
关键词 wireless sensor network network lifetime moving scheme residual energy
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A novel non-separation opening scheme of front cover for rocket launch canister 被引量:2
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作者 Ce Zhang Xin Zhao +2 位作者 Zonglai Mo Zhuoyu Guo Jun Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第6期905-911,共7页
In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separat... In view of that existing opening technologies of front cover for rocket launch canister have disadvantages such as causing damage on the ground equipment,not being reused and easily broken.A novel reusable non-separation spring-driven opening scheme is proposed to achieve rapid and reliable opening of the front cover.The mathematical model of the opening process of the front cover is established by the rigid body dynamics theory.To establish a response surface model to optimize the opening scheme,three main influencing factors of the opening process are obtained through the designed experiments,including the pre-compression,the stiffness of the thrust spring,and the thrust spring force arm length.In addition,the prescribed kinematic law was taken as constraint,and the smaller thrust spring preliminary pressure and angular velocity was taken as optimization expectations.The results show that the opening scheme meets the design requirements on opening process well.It also shows that the optimized scheme can reduce the kinetic energy of the front cover,and the impact on the canister effectively,achieving a reliable and rapid opening of the front cover. 展开更多
关键词 Canister covers Spring-driven Non-separation Optimized opening scheme Rocket launch canisters Launch safety
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High-end equipment development task decomposition and scheme selection method 被引量:4
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作者 XU Xiangqian YANG Kewei +3 位作者 DOU Yajie ZHOU Zhexuan CHEN Ziyi TAN Yuejin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期118-135,共18页
Decomposition of tasks and selection of optimal schemes are key procedures in high-end equipment development processes.However,such procedures are highly innovative,technology intensive,interdisciplinary,and multi-par... Decomposition of tasks and selection of optimal schemes are key procedures in high-end equipment development processes.However,such procedures are highly innovative,technology intensive,interdisciplinary,and multi-party engineering projects,making the decomposition and scheme selection more difficult and complicated than that in the development of ordinary equipment.In this study,we consider three factors,namely,functional structure,task granularity,and task feasibility in task decomposition of high-end equipment development.Based on the principles of systems engineering,a method of task decomposition is proposed.As for decomposition scheme selection,a method based on the superiority and inferiority ranking(SIR)method mixed information and multiple attribute decision making is proposed by considering attributes of scheme feasibility,uncertainty risk and task integration complexity.To verify the proposed method,development of a military electric vehicle is used as an example to demonstrate the calculation process. 展开更多
关键词 high-end equipment task decomposition decomposition scheme selection
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Traffic assignment problem under tradable credit scheme in a bi-modal stochastic transportation network: A cumulative prospect theory approach 被引量:3
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作者 HAN Fei ZHAO Xiang-mo CHENG Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期180-197,共18页
The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertain... The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertainty, the cumulative prospect theory(CPT) is adopted. Travelers are assumed to choose the paths with the minimum perceived generalized path costs, consisting of time prospect value(PV) and monetary cost. At equilibrium with a given TCS, the endogenous reference points and credit price remain constant, and are consistent with the equilibrium flow pattern and the corresponding travel time distributions of road sub-network. To describe such an equilibrium state, the CPT-based stochastic user equilibrium(SUE) conditions can be formulated under TCS. An equivalent variational inequality(VI) model embedding a parameterized fixed point(FP) model is then established, with its properties analyzed theoretically. A heuristic solution algorithm is developed to solve the model, which contains two-layer iterations. The outer iteration is a bisection-based contraction method to find the equilibrium credit price, and the inner iteration is essentially the method of successive averages(MSA) to determine the corresponding CPT-based SUE network flow pattern. Numerical experiments are provided to validate the model and algorithm. 展开更多
关键词 tradable credit scheme cumulative prospect theory endogenous reference points generalized path costs stochastic user equilibrium variational inequality model heuristic solution algorithm
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Splitting Based Scheme for Three-dimensional MHD with Dual Time Stepping 被引量:1
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作者 FU Huazheng FENG Xueshang 《空间科学学报》 CAS CSCD 北大核心 2015年第1期9-17,共9页
A new hybrid numerical scheme of combining an E-CUSP(Energy-Convective Upwind and Split Pressure) method for the fluid part and the Constrained Transport(CT) for the magnetic induction part is proposed.In order to avo... A new hybrid numerical scheme of combining an E-CUSP(Energy-Convective Upwind and Split Pressure) method for the fluid part and the Constrained Transport(CT) for the magnetic induction part is proposed.In order to avoid the occurrence of negative pressure in the reconstructed profiles and its updated value,a positivity preserving method is provided.Furthermore,the MHD equations are solved at each physical time step by advancing in pseudo time.The use of dual time stepping is beneficial in the computation since the use of dual time stepping allows the physical time step not to be limited by the corresponding values in the smallest cell and to be selected based on the numerical accuracy criterion.This newly established hybrid scheme combined with positivity preserving method and dual time technique has demonstrated the accurateness and robustness through numerical experiments of benchmark problems such as the 2D Orszag-Tang vortex problem and the3 D shock-cloud interaction problem. 展开更多
关键词 SPLITTING BASED scheme THREE-DIMENSIONAL MHD Dual time STEPPING
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Secret sharing scheme with inherited characteristic 被引量:1
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作者 Ye Zhenjun Meng Fanzhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期916-918,共3页
To assure the shareholders can look for their "legal" attorneys to renew the secret, once the secret sharing scheme is initialized, a secret sharing scheme with inherited characteristic is constructed. In this schem... To assure the shareholders can look for their "legal" attorneys to renew the secret, once the secret sharing scheme is initialized, a secret sharing scheme with inherited characteristic is constructed. In this scheme, each shareholder can produce a new share by his algorithm, which is equivalent to the primary one. Together with other shares, the primary secret can be renewed. Since this scheme is constructed not by replacing the primary share with a new share produced by the dealer in his primitive secret sharing scheme, so no matter how much shares the shareholder produces, these shares can not be gathered together to renew the secret in this scheme. Compared with the existing secret sharing schemes, this scheme provides more agility for the shareholders by investing each of them a function but not affect its security. 展开更多
关键词 CRYPTOGRAPHY secret sharing scheme INHERITED equivalent class.
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