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VCR-LFM-BPSK signal design for countering advanced interception technologies

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Journal of Systems Engineering and Electronics 2021年第2期32卷 380-388页

作者： wang shanshan LIU Zheng XIE Rong wang Jingjing National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

The hybrid waveform of linear frequency modulation and binary phase shift keying(LFM-BPSK)can take advantages of the LFM and BPSK signals,and reduce the defects of ***,with the development of interception technology for the LFM-BPSK signal,the application of the signal is *** this paper,to improve the anti-interception performance of the hybrid waveform,a new waveform of LFM-BPSK with the varying chirp rate(denoted as VCR-LFM-BPSK)is *** this design,based on the working principle of the interception frame for the LFM-BPSK signal,different chirp rates are introduced in different sub-pulses to prevent the signal from being intercepted by the ***,to further improve the anti-interception performance of the VCR-LFM-BPSK signal,the chirp rates are optimized by minimizing the interception capability of the ***,based on the VCR-LFM-BPSK signal with the optimized chirp rates,the binary phases are designed via a multiobjective Pareto optimization to improve the capabilities of autocorrelation and *** results demonstrate that the designed VCR-LFM-BPSK signal outperforms the traditional LFM-BPSK signal in countering the advanced interception technologies.

关键词： hybrid waveform waveform design anti-interception optimization

Relationship between local damage and structural dynamic behavior

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Science China(Technological Sciences) 2012年第12期55卷 3257-3262页

作者： wang shanshan REN QingWen College of Mechanics and Materials Hohai UniversityNanjing 210098China

Damage in the structures alters the structural dynamic behavior. Damage generally occurs locally in the components of structures, and its effect often exhibits in the changes of both local and global characteristics of structures. Better understanding of this relationship helps to monitor and assess the condition of structures and develop dynamics-based structural health monitoring techniques. In this study, the relationship between the local damage and structural dynamic behavior is investigated. To validate the concept, an experiment of a three-dimensional (3-D) steel frame structure with different magnitudes of local damage is illustrated. The experimental results indicate that the change of global resonant response between the intact and damage structure is not obvious. The change of local resonant responses measured near the location of saw-cut crack damage is quite significant. The experimental study conducted indicates that the local resonant responses at the low order resonance can be used as an effective damage identification method to detect and quantify the local damage in the 3D frame structures.

关键词： local damage dynamic behavior relationship global resonant response local resonant response

Dynamic response of gravity dam model with crack and damage detection

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Science China(Technological Sciences) 2011年第3期54卷 541-546页

作者： wang shanshan REN QingWen College of Mechanics and Materials Hohai University Nanjing 210098 China

Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynamic response of structure with damage and associated damage detection method. In order to study thoroughly the dynamic behavior of gravity dam with damage, the sweep vibration responses of the gravity dam with and without damage are investigated. The experimental results show that the peak-peak acceleration responses all increase for the structure is with crack. At the same time, a structural damage detection method, i.e., the local damage factor (LDF) method, is considered in the study of gravity dam damage detection when the dam is subjected to the base excitation. It is shown that the LDF method can be used as a damage index and is capable of evaluating both the presence and relative severity of structural damage, and it can be used as a viable condition assessment and damage identification technique to detect and quantify the damage in the gravity dam.

关键词： gravity dam dynamic response crack sweep damage detection local damage factor

Statistical regression modeling for energy consumption in wastewater treatment

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Journal of Environmental Sciences 2019年第1期31卷 201-208页

作者： Yang Yu Zhihong Zou shanshan wang School of Economics and Management Beihang University Beijing Key Laboratory of Emergence Support Simulation Technologies for City Operations

Wastewater treatment is one of critical issues faced by water utilities, and receives more and more attentions recently. The energy consumption modeling in biochemical wastewater treatment was investigated in the study via a general and robust approach based on Bayesian semi-parametric quantile regression. The dataset was derived from a municipal wastewater treatment plant, where the energy consumption of unit chemical oxygen demand(COD) reduction was the response variable of interest. Via the proposed approach,the comprehensive regression pictures of the energy consumption and truly influencing factors, i.e., the regression relationships at lower, median and higher energy consumption levels were characterized respectively. Meanwhile, the proposals for energy saving in different cases were also facilitated specifically. First, the lower level of energy consumption was closely associated with the temperature of influent wastewater, and the chroma-rich wastewater also showed helpful in the execution of energy saving. Second, at median energy consumption level, the COD-rich wastewater played a determinative role in the reduction of energy consumption, while the higher quality of treated water led to slightly energy intensive. Third, the higher level of energy consumption was most likely to be attributed to the relatively high temperature of wastewater and total nitrogen(TN)-rich wastewater,and both of the factors were preferably to be avoided to alleviate the burden of energy consumption. The study provided an efficient approach to controlling the energy consumption of wastewater treatment in the perspective of statistical regression modeling, and offered valuable suggestions for the future energy saving.

关键词： Energy consumption modeling Wastewater treatment Semi-parametric model Bayesian quantile regression

Gerber-Shiu function of a discrete risk model with and without a constant dividend barrier

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Frontiers of Mathematics in China 2015年第2期10卷 377-393页

作者： shanshan wang Chuangji AN Chunsheng ZHANG Department of Mathematics Tianjin Polytechnic University Tianjin 300387 China School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

We consider the discrete risk model with exponential claim sizes. We derive the finite explicit elementary expression for the joint density function of three characteristics： the time of ruin, the surplus immediately before ruin, and the deficit at ruin. By using the explicit joint density function, we give a concise expression for the Gerber-Shiu function with no dividends. FinMly, we obtain an integral equation for the Gerber-Shiu function under the barrier dividend strategy. The solution can be expressed as a combination of the Gerber-Shiu function without dividends and the solution of the corresponding homogeneous integral equation. This latter function is given clearly by means of the Gerber- Shiu function without dividends .

关键词： Discrete risk model Gerber-Shiu function time of ruin surplus before ruin deficit at ruin dividend

Response of grease film at low speeds under pure rolling reciprocating motion

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Friction 2020年第1期8卷 115-135页

作者： Yiming HAN Jing wang shanshan wang Qian ZOU Gary BARBER School of Mechanical and Automotive Engineering Qingdao University of TechnologyHuangdao CampusQingdao 266520China School of Engineering and Computer Science Oakland UniversityRochesterMI 48309USA

Using an optical interferometric technique,the grease film distribution under a pure rolling reciprocating motion is observed on a ball‐disk test rig,to explore the transient response of grease,which is expected to fill the contact with thickener fiber and run for a long time under steady‐state *** is found that the reciprocating motion reduces the accumulation of the thickener fiber gradually with *** maximum film thickness forms around the stroke *** 1,000 working cycles,very severe starvation occurs so that either the central or minimum film thickness becomes nearly constant over one working ***,the life of grease lubrication under a transient condition is far below that under steady‐state ***,it is also found that by selecting a smaller stroke length,the thickener fiber spreads out in the contact instead of being removed from the contact at the 1,000th working *** increasing the maximum entraining speed of the reciprocating motion to a certain value,during which the thickener fiber is not expected to accumulate under a steady‐state condition,severe starvation occurs very quickly,causing surface damage.

关键词： grease lubrication reciprocation pure rolling grease starvation thickener fiber

Recovery of natural active molecules using aqueous two-phase systems comprising of ionic liquids/deep eutectic solvents

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Green Chemical Engineering 2022年第1期3卷 5-14页

作者： Yicong wang shanshan wang Leilei Liu Key Laboratory of Hunan Forest Products and Chemical Industry Engineering Jishou UniversityZhangjiajie427000China

Due to environmental protection requirements,extraction of bioactive compounds from plant materials using environment-friendly green solvents has always been a research *** great efforts of scholars have been made in this direction,as well as environment-friendly solvents have been used to develop many innovative extraction *** liquids(ILs)and deep eutectic solvents(DESs)are two kinds of typical designable green solvents,which are potential replacements for traditional volatile organic solvents used for *** the substances action of inorganic salts or polymers,ILs/DESs can form an aqueous two-phase system(ATPS),which has obvious advantages for separating natural *** paper discussed the phase separation principle of ILs/DESs-based ATPSs and reviewed the applications in the extraction of natural active molecules in recent years,as well as to promote the development of separation of the active constituents in Chinese materia medica.

关键词： Ionic liquids Deep eutectic solvents Aqueous two-phase system Natural active molecules Extraction and separation

Application of in situ/operando characterization techniques in heterostructure catalysts toward water electrolysis

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Nano Research 2023年第2期16卷 1984-1991页

作者： Wanyi Liao shanshan wang Hong Su Yan Zhang Sichuan Engineering Research Center for Biomimetic Synthesis of Natural Drugs School of Life Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The key to achieving the breakthrough of hydrogen energy from marginal energy sources in large scale applications lies in the development and design of efficient electrocatalysts for the electrochemical oxidation and reduction of *** unique heterostructure endows the catalyst with a mass of functional interfaces that are decisive for the enhancement of catalyst activity,stability,and reaction *** some cutting-edge reviews have focused on the synthesis strategies,constitution,and applications of heterostructure catalysts,the field still lacks a detailed discussion of the actual reaction processes occurring at the interface,which is detrimental to the understanding of the true catalytic *** on advanced in situ/operando characterization techniques to understand the working mechanism of heterostructure catalysts is essential for rational design of advanced *** this review,we first present the advantages of heterostructure catalysts applied to electrolyzing ***,the application of in situ/operando techniques in probing three aspects of heterostructure catalyst surface reconstruction,reaction mechanism,and the role of each component is highlighted with classical case ***,the current challenges and prospects for the design of heterostructure electrocatalysts are discussed in detail.

关键词： in situ/operando characterization heterostructure reconfiguration reaction mechanism electrochemical water splitting

Influence factors and variation characteristics of water vapor absorption by soil in semi-arid region

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Science China Earth Sciences 2016年第11期59卷 2240-2251页

作者： ZHANG Qiang wang Sheng wang shanshan ZHAO YingDong WEN XiaoMei Key Laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province Key Open Laboratory of Arid Climate Change and Disaster Reduction of CMA Institute of Arid Meteorology Lanzhou 730020 China Gansu Meteorological Bureau Lanzhou 730020 China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Hydrology and Water Resources Bureau of Gansu Province Lanzhou 730000 China Shanghai Meteorological Service Shanghai 201901 China

The adsorption of water vapor by soil is one of the crucial contributors to non-rainfall water on land surface, particularly over semi-arid regions where its contribution can be equivalent to precipitation and can have a major impact on dry agriculture and the ecological environment in these regions. However, due to difficulties in the observation of the adsorption of water vapor,research in this area is limited. This study focused on establishing a method for estimating the quantitative observation of soil water vapor adsorption(WVA), and exploring the effects of meteorological elements(e.g., wind, temperature, and humidity) and soil environmental elements(e.g., soil temperature, soil moisture, and the available energy of soil) on WVA by soil over the semi-arid region, Dingxi, by combining use of the L-G large-scale weighing lysimeter and meteorological observation. In addition, this study also analyzed the diurnal and annual variations of WVA amount, frequency, and intensity by soil, how they changed with weather conditions, and the contribution of WVA by soil to the land surface water budget. Results showed that WVA by soil was co-affected by various meteorological and soil environmental elements, which were more likely to occur under conditions of relative humidity of 6.50% and the diurnal variation of relative humidity was large, inversion humidity, wind velocity of 3.4 m/s,lower soil water content, low surface temperature and slightly unstable atmospheric conditions. There was a negative feedback loop between soil moisture and the adsorption of water vapor, and, moreover, the diurnal and annual variations of WVA amount and frequency were evident—WVA by soil mainly occurred in the afternoon, and the annual peak appeared in December and the valley in June, with obvious regional characteristics. Furthermore, the contribution of WVA by soil to the land surface water budget obviously exceeded that of precipitation in the dry season.

关键词： Semi-arid region Water vapor adsorption Micro-meteorological elements Soil environment Water budget