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Analysis on influencing factors of detecting chemical oxygen demand in water by ultraviolet absorption spectroscopy

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Optoelectronics Letters 2022年第12期18卷 749-754页

作者： ZHOU Kunpeng LIU Zhiyang CONG Menglong man shanxin Intelligent manufacturing Technology Key Laboratory Intelligent Agricultural Machinery Equipment&Technology TeamCollege of EngineeringInner Mongolia Minzu UniversityTongliao028000China College of Information Engineering Jingzhou University(College of Engineering and Technology Yangtze University)Jingzhou434000China Alxa League Meteorological Bureau Alxa750300China

Taking the standard solution and actual water samples as the research object, this paper studies the influence of various environmental factors(temperature, alkalinity(pH), inorganic salt ions and salinity) on the detection of chemical oxygen demand(COD) in water by ultra-violet(UV) spectrometry, analyzes the influence mechanism, and draws relevant conclusions. The results show that the UV absorbance of the COD standard solution and the actual river water samples varies very little with temperature. The value of pH has certain impact on both the standard solution and the actual water samples, but the pH values of the affected experimental samples are in different ranges. The effects of nitrogen salt ions(NO_(2)^(-)and NO_(3)^(-)) on the UV absorption spectra can be eliminated by intercepting the UV spectrum interval less affected for modeling. The influence of salinity values below 35‰ on the UV absorption spectrum of water is mainly concentrated in the spectral band of 200—250 nm, and the influence above 250 nm is very little. This paper provides a preliminary analysis and discussion on the influence mechanism and laws of various environmental factors in the detection of water quality parameters by UV spectrometry, which provides an experimental basis for selecting the optimal test conditions when establishing the COD prediction model.

关键词： absorption chemical mechanism

Detection of chemical oxygen demand in water based on UV absorption spectroscopy and PSO-LSSVM algorithm

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Optoelectronics Letters 2022年第4期18卷 251-256页

作者： ZHOU Kunpeng LIU Zhiyang CONG Menglong man shanxin College of Engineering Intelligent Manufacturing Technology Key LaboratoryInner Mongolia Minzu UniversityTongliao 028000China Jingzhou University Jingzhou 434000China Alxa League Meteorological Bureau Alxa 750300China

A method of detecting chemical oxygen demand(COD) of water based on ultraviolet(UV) absorption spectra is proposed. The modeling and analysis of the standard samples and the actual water samples are carried out respectively. For the standard solution samples, the univariate linear models based on single wavelengths and the partial least square(PLS) model based on synergy interval partial least square(Si PLS) and moving window partial least square(MWPLS) are established. For the actual water samples, different pre-processing methods are used. Si PLS and MWPLS are used to select the characteristic bands. The least squares support vector machine algorithm optimized by particle swarm optimization(PSO-LSSVM) algorithm is used to establish the prediction model, and the prediction results of various models are compared. The results show that the optimal model is PSO-LSSVM which uses Si PLS to select the characteristic bands of the first derivative spectra(preprocessing method). The determination coefficient of the prediction set is 0.963 1, and the root mean square error of prediction(RMSEP) is 2.225 4 mg/L. PSO-LSSVM algorithm has good prediction performance for the analysis of COD in actual water samples by UV spectra. This paper provides a new design idea for the research and development of water quality detection optical sensor.

关键词： algorithm prediction bands

Migration and distribution characteristics of soil heavy metal(loid)s at a lead smelting site

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Journal of Environmental Sciences 2024年第1期135卷 600-609页

作者： Chuxuan Li Mu Li Jiaqing Zeng shanxin Yuan Xinghua Luo Chuan Wu Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China

Heavy metal(loid)s contamination is a constant issue at smelting sites.It is essential to investigate the spatial distribution and migration characteristics of heavy metal(loid)s in the soil for environmental management and remediation strategies of non-ferrous smelting sites.In this study,203 soil samples from 57 sites were collected in a typical lead smelting site.The findings demonstrated that there were significant Pb,Zn,Cd,and As contamination in soil samples.The spatial distribution of heavy metal(loid)s showed strong spatial heterogeneity,the contaminated soil areas of Pb,As,Cd,and Zn were 99.5%,98.9%,85.3%,and 72.4%,respectively.Pb,Cd,and As contamination of the soil reached a depth of 5 m,which migrated from the surface to deep soil layers.The leaching contents of Zn,Pb,and As decreased obviously in 3-4 m soil layer,but the leaching content of Cd was still high,which indicated the high migration of Cd.With the increase of depth,the proportion of acid soluble fraction of heavy metal(loid)s decreased,and the residual fraction increased.The acid soluble fraction of Cd accounted for a higher proportion,and As mainly existed in reducible and residual fractions in soil.According to the calculation of the migration factor,the migration of heavy metal(loid)s in soils were ordered as Cd>Zn>Pb>As.The outcomes are advantageous for risk reduction and site remediation for non-ferrous metal smelting sites.

关键词： Smelting sites Heavy metal(loid)s Spatial distribution Chemical speciation Migration characteristics

无人机辅助MEC系统中的联合计算卸载和轨迹设计

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武汉理工大学学报（交通科学与工程版） 2024年第1期48卷 7-12页

作者：许晨旭曹润宇薛志钢张善新江苏省特种设备安全监督检验研究院无锡214025 江南大学物联网工程学院无锡214122

文中提出了一种无人机辅助移动边缘计算(MEC)系统,其中一架配备计算资源的无人机作为飞行基站(BS)处理从用户迁移来的应用任务,以节省用户设备的能耗.考虑了一种通用的瑞森衰落信道模型,通过联合优化无人机轨迹、用户发射功率、用户调... 详细信息

文中提出了一种无人机辅助移动边缘计算(MEC)系统,其中一架配备计算资源的无人机作为飞行基站(BS)处理从用户迁移来的应用任务,以节省用户设备的能耗.考虑了一种通用的瑞森衰落信道模型,通过联合优化无人机轨迹、用户发射功率、用户调度和比特分配,以最小化所有用户设备的平均能耗.设计了一种基于迭代分块连续上界最小化算法,并引入二次惩罚项进行交替求解.结果表明:文中所提出的联合优化方案优于其他基准方案,能显著降低用户的能量消耗.

关键词：移动边缘计算无人机能量消耗计算卸载轨迹优化

熵权法改进的模糊数学滑坡稳定性评价方法研究

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中国地质灾害与防治学报 2024年第1期35卷 19-27页

作者：霍善欣王新刚薛晨王友林李琦刘凯大陆动力学国家重点实验室(西北大学地质学系) 陕西西安710069 陕西省水工环地质调查中心陕西西安710068

滑坡是中国最为常见的一种地质灾害类型,其具有的易发、频发特点使得人民的生命财产安全受到了严重的威胁,滑坡的稳定性评价是滑坡防灾减灾工作中最为关键的一项工作。鉴于滑坡诱发因素具有模糊性的特点,文章以陕西省勉县新铺镇发育的... 详细信息

滑坡是中国最为常见的一种地质灾害类型,其具有的易发、频发特点使得人民的生命财产安全受到了严重的威胁,滑坡的稳定性评价是滑坡防灾减灾工作中最为关键的一项工作。鉴于滑坡诱发因素具有模糊性的特点,文章以陕西省勉县新铺镇发育的典型堆积层滑坡为例,在地质环境条件分析的基础上,考虑了采用模糊数学法进行滑坡稳定性评价,并引入热力学中“熵”的概念,采用熵权法确定了滑坡诱发因子的权重,进而提出了一种基于熵权法改进的模糊数学滑坡稳定性评价新方法。结果表明:新提出的基于熵权法改进的模糊数学滑坡稳定性评价方法克服了传统模糊综合评价方法主观性判断滑坡影响因子权重的弊端;通过数值模拟法进行滑坡稳定性定量化分析验证,发现两种方法评价结论较为吻合,说明了所提出的新方法具有一定的可靠性。基于熵权法改进的模糊数学滑坡稳定性评价方法较为快速简捷,可用于临灾快速预警、应急救援等突发情况下的滑坡防灾减灾工作。

关键词：模糊综合评价熵权法数值模拟滑坡稳定性分析

金属有机框架衍生的Co_(3)O_(4)/SnO_(2)复合材料制备及其光催化性能

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上海大学学报（自然科学版） 2024年第1期30卷 54-67页

作者：吴函鸿刘善鑫王大卫黄茹婷陈志文安徽大学资源与环境工程学院合肥230601 安徽大学湿地生态保护与修复安徽省重点实验室合肥230601 上海大学环境与化学工程学院上海200444

金属有机框架(metal-organic framework,MOF)材料ZIF-67衍生Co_(3)O_(4)十二面体纳米块在室温下与SnO_(2)复合,制备出立方体Co_(3)O_(4)/SnO_(2)复合光催化剂.煅烧后形成的Co_(3)O_(4)/SnO_(2)材料禁带宽度明显降低,荧光淬灭明显,说明Co_(3)O_(4)的加入拓展了SnO_(2)的光响应范围至可见光甚至红外光区域,同时促进了光催化反应过程中光生载流子的分离.以罗丹明B(Rhodamine B,Rh B)为目标反应物,在可见光下考察了MOF衍生的Co_(3)O_(4)/SnO_(2)的光催化降解活性,发现Co_(3)O_(4)/SnO_(2)在60 min内可以降解89.6%的Rh B,分别是纯SnO_(2)和纯ZIF-67的4.5倍和3倍.同时,Co_(3)O_(4)/SnO_(2)表现出了良好的光反应能力和稳定性.基于以上实验结果并结合自由基淬灭实验,提出了MOF衍生的Co_(3)O_(4)/SnO_(2)复合材料光催化降解有机染料RhB的机理.

关键词： Co_(3)O_(4)/SnO_(2) 金属有机框架光催化机理

An indoor fusion navigation algorithm using HV-derivative dynamic time warping and the chicken particle flter

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Satellite Navigation 2022年第1期3卷 167-184,I0005页

作者： Jian Chen Shaojing Song Yumei Gong shanxin Zhang School of Computer and Information Engineering Shanghai Polytechnic UniversityShanghai 200000China School of Computer and Information Engineering Shandong Normal UniversityJinanChina

The use of dead reckoning and fngerprint matching for navigation is a widespread technical method.However,fngerprint mismatching and low fusion accuracy are prevalent issues in indoor navigation systems.This work presents an improved dynamic time warping and a chicken particle flter to handle these two challenges.To generate the Horizontal and Vertical(HV)fngerprint,the pitch and roll are employed instead of the original fngerprint intensity to extract the horizontal and vertical components of the magnetic feld fngerprint.Derivative dynamic time warping employs the HV fngerprint in its derivative form,which receives higher-level features because of the consideration of fngerprint shape information.Chicken Swarm Optimization(CSO)is used to enhance particle weights,which minimizes position error to tackle the particle impoverishment problem for a fusion navigation system.The results of the experiments suggest that the enhanced algorithm can improve indoor navigation accuracy signifcantly.

关键词： An indoor fusion navigation algorithm HV-derivative dynamic time warping Chicken particle flter

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基于SDN的通信网络管理策略分析

集成电路应用 2024年第4期41卷 335-337页

作者：王超冯瑞佳苟洋李善鑫 95577部队云南655601

阐述SDN的基本原理,探讨SDN通信网络管理的优势,它能够提高网络效率、增强网络安全性。分析SDN通信网络管理面临的挑战和解决方案,以及未来发展趋势和预测。SDN通过其集中式管理、可编程性、虚拟化能力和自动化能力,为通信网络管理提供... 详细信息

阐述SDN的基本原理,探讨SDN通信网络管理的优势,它能够提高网络效率、增强网络安全性。分析SDN通信网络管理面临的挑战和解决方案,以及未来发展趋势和预测。SDN通过其集中式管理、可编程性、虚拟化能力和自动化能力,为通信网络管理提供了新的可能性。

关键词：软件定义网络(SDN) 网络管理策略流量管理网络效率

Workflow optimization algorithm based on virtualization and nonlinear production quality under time constraints

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The Journal of China Universities of Posts and Telecommunications 2023年第4期30卷 55-66页

作者： Luo Zhiyong Tan shanxin Xu Haifeng Liu Xintong School of Computer Science and Technology Harbin University of Science and TechnologyHarbin 150080China

Balancing time,cost,and quality is crucial in intelligent manufacturing.However,finding the optimal value of production parameters is a challengingnon-deterministic polynomial(NP)-hard problem.In the actual production process,the production process has the characteristics of multi-stage parallel.Therefore,aiming at the difficult problem of multi-stage nonlinear production process optimization,this paper proposes a workflow optimization algorithm based on virtualization and nonlinear production quality under time constraints(T-OVQT).The algorithm proposed in this paper first abstracts the actual production process into a virtual workflow model,which is divided into three layers:The bottom production process collection layer,the middle layer of service node partial order composition layer,and the high level of virtual node collection layer.Then,the virtual technology is used to reconstruct the node set and divide the task interval.The optimal solution is obtained through inverse iterative normalization and forward scheduling,and the global optimal solution is obtained by algorithm integration.Experimental results demonstrate that this algorithm better meets actual production requirements than the traditional minimum critical path(MCP)algorithm.

关键词： work-flow optimize scheduling virtual node production quality virtual technology