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Study on the characteristics of dolphins click signal

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Study on the characteristics of dolphins click signal

作者： ZHANG Zhaohui PENG Yuan Science and Technology on Underwater Test and Control Laboratory

Dolphins have a strong ability of target identification in the ocean, how to use it has become a new field of *** is mainly divided into three categories in the research of dolphin communication signals namely whistle, click and emergency signals. Dolphin Click sound is mainly used for target detection and recognition. In this paper, the research group designed a pool experiment to obtain the click signal when dolphin identify rubber bar, reef, aluminum bar and steel ball, and analyzes the signal form, frequency, spectrum change rule and other information from the perspective of time domain and time-frequency domain. The number of sine waves in click signal is analyzed when dolphins identify four kind of targets. We summarize six kinds of spectrum forms to classify the acquired acoustic signals, the probability of each spectrum form is analyzed and counted when dolphins detect and identify different *** results show that the click signal emitted by dolphins in target recognition is mainly one waveform click signal. The main energy of the frequency is concentrated at 0-200 khz.

关键词： Dolphin Click Signal Processing

Experimental Study on Forward Acoustic Scattering in Stratified Water Turbulence

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Experimental Study on Forward Acoustic Scattering in Stratif...

作者： Jintao Yong Yunfei Chen Zhenshan Wang Bing Jia Rui Wang Jianglin Wu Science and Technology on Underwater Test and Control Laboratory

In this thesis, the forward acoustic scattering characteristics of two kinds of turbulence are experimentally tested and studied through the stratified tank simulation experiment. The fluctuation of the amplitude of the turbulent forward acoustic scattering signal with space and time is analyzed. The turbulent forward acoustic scattering intensity at different detection points in space and the variation trend of the turbulent forward acoustic scattering intensity at the same detection point with time are obtained. The experimental results show that the amplitude fluctuation frequency of the forward acoustic scattering signal decreases with time. In the density thermocline, the changing trend of the amplitude and transmission time of the acoustic signal at the adjacent position in the horizontal direction with time is similar, and the magnitude value is equivalent. The changing trend and magnitude of the acoustic signal amplitude at the adjacent depth in the vertical direction are different. The turbulence intensity has a significant impact on the amplitude fluctuation of forward acoustic scattering signal.

关键词： Turbulence Forward acoustic scattering Experimental test

Apple microbial communities and differences between two main Chinese producing regions

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Food Quality and Safety 2022年第1期6卷 34-44页

作者： Youming Shen Jianyi Zhang Jiyun Nie Hui Zhang Syed Asim Shah Bacha College of Horticulture Qingdao Agricultural University/Laboratory of Quality&Safety Risk Assessment for Fruit(Qingdao)Ministry of Agriculture and Rural Affairs/National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products(Qingdao)/Qingdao Key Lab of Modern Agriculture Quality and Safety EngineeringQingdaoChina Institute of Pomology Chinese Academy of Agricultural Sciences/Laboratory of Quality&Safety Risk Assessment for Fruit(Xingcheng)Ministry of Agriculture and Rural Affairs/Quality Inspection and Test Center for Fruit and Nursery Stocks(Xingcheng)Ministry of Agriculture and Rural AffairsXingchengChina

Microbes on fresh apples are closely associated with fruit disease,preservation,and quality *** into the microbial commu-nities on apples from different producing regions could reveal the microbial specificity and help disease prevention and quality *** this paper,the apple surface microbes of 44 samples from two main Chinese apple-producing regions,Bohai Bay(BHB)and the Loess Plateau(LP),were investigated by sequencing fungal internal transcribed spacer and bacterial 16s rRNA hypervariable *** and LP apples con-tained significantly different bacterial and fungal *** apples had a higher fungal diversity than LP apples.A total of 102 different fungal and bacterial taxonomies were obtained between apples from the two regions,in which 24 genera were *** apples had higher phytopathogenic fungal genera,such as Tilletiopsis,Acremonium,Candida,and Phoma,indicating the higher phytopathogenic risks of apples from the humid climate of the BHB *** apples contained more bacterial genera identified as gut microbes,indicating the potential risks of contaminating apples with foodborne pathogens in the arid environment of the LP This study highlighted the environment-oriented mi-crobial specificity on apples from two main apple-producing regions,and provided a basis for further investigation.

关键词： Apple regional climate microbiome metagenomics next generation sequencing

control design under attacks of multi-agent switched systems via arbitrary switching

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Control design under attacks of multi-agent switched systems...

2022 Chinese Automation Congress, CAC 2022

作者： Li, Zhanjie Ma, Yajing Nanjing University of Posts and Telecommunications Institute of Advanced Technology for Carbon Neutrality Nanjing China Sichuan Xihua University Provincial Engineering Research Center for New Energy Vehicle Intelligent Control and Simulation Test Technology Chengdu China School of Internet of Things Jiangsu Key Laboratory of Broadband Wireless Communication and Internet of Things Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9781665465335

In this paper, the consensus control against attacks for a type of nonlinear multi-agent switched systems under arbitrary switching is studied. The attacks corrupt the information data, which cannot be used for the feedback design. Meanwhile, the switching logic is not allowed to be designed. To tackle the complicated effects, some intermediate variables and adaptive laws are introduced to compensate the uncertainties. By constructing a common Lyapunov function, an adaptive protocol is proposed such that the outputs of the agents achieve consensus against attacks under arbitrary switching. © 2022 IEEE.

关键词： Multi agent systems

Enhancing Vehicular Emissions Monitoring: A Ga-Gru-Based Soft Sensors Approach for Hddvs

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SSRN 2023年

作者： Yang, Luoshu Lyu, Liqun Tan, Jianwei Hao, Lijun Wang, Xin Yin, Hang Wang, Junfang Ge, Yunshan School of Mechanical Engineering Beijing Institute of Technology Beijing100081 China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental Sciences Beijing100012 China National Laboratory of Automotive Performance & Emission Test

The continuous release of pollutants has posed a significant threat to both public health and the sustainability of the environment. Consequently, governments across the globe have introduced more stringent rules pertaining to vehicle emissions to address this issue. In addition, the Portable Emission Measurement System (PEMS) is now the most widely used approach for detecting NOx and PN emissions from heavy-duty vehicles on real roads. However, this technology is associated with significant requirements in terms of human labor and resources, making it both expensive and time-consuming. Hence, it is imperative to put up a novel approach for the surveillance of actual on-road emissions. Prior research has indicated the potential of employing soft sensors as an alternative to physical sensors for the purpose of CO2 monitoring. However, there exists a scarcity of scholarly investigations pertaining to the monitoring of NOx and PN. The present study presents a soft sensor based on a combination of genetic algorithm (GA) and gated recurrent unit (GRU) for the purpose of monitoring real-time emissions of nitrogen oxides (NOx) and particle number (PN) within the on-board diagnostics (OBD) system. This research addresses the existing research gap in the development of soft sensors specifically designed for NOx and PN emissions. In this study, we present evidence that the described soft sensor exhibits exceptional R2 values and outperforms other conventional models. Our findings illustrate the potential of the described soft sensor to operate by effectively eliminating outliers accurately and promptly and consistently tracking predictions over the lifespan of the vehicle. Moreover, our model exhibits a high degree of reusability in the domain of emissions prediction and possesses significant potential for addressing more stringent emission rules and emerging gas pollutant constituents in forthcoming times. © 2023, The Authors. All rights reserved.

关键词： Genetic algorithms

Molybdenum Doping Leads to Faster Photo-Dissolution of Commercial Molybdate Red Pigment than Chrome Yellow Pigment Under Sunlight Irradiation

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SSRN 2024年

作者： Liu, Huiting Zhang, Shuangshuang Qu, Xiaolei Fu, Heyun Zuo, Linzi School of Environmental and Chemical Engineering Shenyang Ligong University Liaoning 110159 China State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Jiangsu210023 China Analysis and Test Center Guangdong University of Technology Guangzhou510006 China

The photo-dissolution of lead chromate pigments poses specific environmental hazards. In particular, the presence of molybdenum in lead chromate molybdate pigments, commonly known as molybdate red, might increase the risk of heavy metal leaching when exposed to light. Our study demonstrates that commercial molybdate red pigments can undergo photo-dissolution when exposed to simulated sunlight and exhibit lower photostability compared to lead chromate pigments such as chrome yellow. After 24 hours of irradiation, the leaching rates of toxic lead (Pb) and chromium (Cr)from molybdate red pigments are 2.98 and 3.70 times higher, respectively, than those from chrome yellow pigments under identical conditions. Molybdate red pigment also exhibits a faster initial release rate of heavy metals. The primary factor leading to decreased pigment photostability is the activation of pigment semiconductors facilitated by molybdenum (Mo)doping. Molybdate red pigments, unlike conventional chrome yellow pigments, exhibit a broader light absorption spectrum and more effective separation and transfer of photogenerated charge carriers. This ultimately boosts the photochemical activity of molybdate red pigments in aqueous environments. Overall, this study indicates that Mo doping can reduce the photostability of lead chromate pigments, highlighting the potential for increased environmental risks associated with complex inorganic metal pigments. © 2024, The Authors. All rights reserved.

关键词： Dissolution

Rapid Prediction Model of Equivalent Thermal Conductivity of Plain Weave Fabric in Space Environment

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SSRN 2023年

作者： Qin, Jiaxing Wu, Jiawen Mu, Lei Zhang, Biao Li, Jian Xu, Chuanlong National Engineering Research Center of Power Generation Control and Safety School of Energy and Environment Southeast University Nanjing210096 China National Key Laboratory of Science and Technology on Test Physics & Numerical Mathematics Beijing100076 China

The prediction of effective thermal conductivity of aerospace insulation materials is crucial for insulation design and radiation characteristics control of space targets. In this paper, a rapid and accurate prediction model is proposed for the effective thermal conductivity of plain weave fabrics in space environments. This model assumes that the cross-sectional shape and bending degree of yarns within aerospace fabrics remain unchanged. To represent the structural characteristics of the plain weave fabric, a dimensionless parameter called "[[EQUATION]]" is defined. Numerical simulations are conducted to investigate the effects of fabric structure, temperature, and yarn thermal properties on the effective thermal conductivity of multilayer fabrics. Three parameters are identified as the most influential factors for the effective thermal conductivity of plain weave fabrics: the structural parameter [[EQUATION]], and the axial and radial thermal conductivities of yarns. Based on extensive simulation data, an empirical formula is proposed for the rapid prediction of the effective thermal conductivity of plain weave fabrics. Moreover, polyester, cotton, and wool plain weave fabric samples are tested for their thermal conductivity in a vacuum environment. The predicted results from the empirical formula proposed in this study exhibit a deviation of less than 6% when compared to experimental measurements. This study can provide valuable insights for the design of plain weave fabrics used in aerospace insulation materials. © 2023, The Authors. All rights reserved.

关键词： Yarn

Cuo2@Sio2 Nanoparticle Assisted Click Reaction-Mediated Magnetic Relaxation Biosensor for Rapid Detection of Salmonella in Food

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SSRN 2024年

作者： Zhao, Junpeng Chen, Rui Ma, Aimin Dong, Yongzhen Han, Minjie Yu, Xuezhi Chen, Yiping Dalian Jinshiwan Laboratory Liaoning Dalian116034 China College of Food Science and Technology Huazhong Agricultural University Shizishan Street Hongshan District Hubei Wuhan430070 China State Key Laboratory of Marine Food Processing and Safety Control Dalian Polytechnic University Liaoning Dalian116034 China Analysis and Test Center Chinese Academy of Tropical Agricultural Sciences Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables Key Laboratory of Quality and Safety Control of Subtropical Fruits and Vegetables Ministry of Agriculture and Rural Affairs Haikou571101 China Key Laboratory of Detection Technology for Animal Derived Food Safety Beijing Laboratory for Food Quality and Safety College of Veterinary Medicine China Agricultural University Beijing100193 China

Foodborne pathogens seriously threaten people's life and well-being. A novel magnetic relaxation time biosensor was constructed by integrating phage, differential magnetic separation technology and copper catalyzed click reaction for rapid and sensitive detection of viable Salmonella typhimurium (S. typhimurium) in food within 80 minutes with linearity range (102-107 CFU/mL) and limit of quantification (80 CFU/mL). This assay employed phage as the recognition element to precisely identify and distinguish viable and nonviable S. typhimurium. We synthesized CuO2@SiO2-phage nanoparticles loaded with numerous Cu2+ ions to convert the concentration of S. typhimurium into the corresponding concentration of copper ions, which then modulate the click reaction between magnetic nanoparticles of different sizes, resulting in alterations in both the number of small magnetic nanoparticles and magnetic signals. The biosensor exhibits exceptional sensitivity and detection time, which has potential applications to various other fields. © 2024, The Authors. All rights reserved.

关键词： Salmonella

A novel malachite green staining approach for evaluating the internal freshness of egg by detecting the quality of egg cuticle

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Food Bioscience 2022年第6期50卷 814-822页

作者： Zixuan Xu Yuliang Liu Fangwei Yang Lijun Huang Hang Yu Weirong Yao Yunfei Xie State Key Laboratory of Food Science and Technology Jiangnan University1800 Lihu AvenueWuxiJiangsu214122China School of Food Science and Technology Jiangnan UniversityNo.1800 Lihu AvenueWuxi214122Jiangsu ProvinceChina Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityNo.1800 Lihu AvenueWuxi214122Jiangsu ProvinceChina Wuxi Food Safety Inspection and Test Center 35-210 Changjiang South RoadWuxi214142Jiangsu ProvinceChina

The cuticle is the outermost protective film of eggs, whose quality will affect internal freshness. At present, the undamaged detection of eggs freshness relies on hyperspectral imaging technology, which is relatively complicated. In this study, a novel simple approach for evaluating internal freshness of eggs was further explored by detecting the quality of egg cuticle. Malachite green selected as the alternative dye for quality evaluation of adhesive film, the correlation analysis was carried out by collecting the physical and chemical indexes of eggs with different degrees of freshness. It is found that there was a strong positive correlation between the quality of all parts of the cuticle and internal freshness (p < 0.01), and the Pearson correlation coefficient was over 0.85. The Haugh unit and pH of albumen were most strongly correlated with cuticle quality at the top, with the correlation coefficient of 0.919 and −0.906, respectively. The cuticle quality of eggs with contents got worse than that of eggs without contents, and the holes increased when they were stored for 28 days. In this way, malachite green staining method can be used to identify the freshness of egg cuticle, and the quality of egg cuticle can be used to distinguish eggs with different freshness. This study provided a new direction for the study of egg freshness and assisted to distinguish the quality and safety of eggs nondestructively.

关键词： Cuticle Egg freshness Bidirectional effect Quality evaluation Correlation analysis