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Optimal combination of the correction model and parameters for the precision geometric correction of UAV hyperspectral images

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 173-184页

作者： Wenzhong Tian za Kan Qingzhan Zhao Ping Jiang Xuewen Wang Hanqing Liu College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina Research Center for Space Information Engineering Technology Shihezi 832000XinjiangChina XPCC Division of National Remote Sensing Center of China Shihezi 832000XinjiangChina College of Information Science and Technology Shihezi UniversityShihezi 832000XinjiangChina

Nowadays,with the rapid development of quantitative remote sensing represented by high-resolution UAV hyperspectral remote sensing observation technology,people have put forward higher requirements for the rapid preprocessing and geometric correction accuracy of hyperspectral *** optimal geometric correction model and parameter combination of UAV hyperspectral images need to be determined to reduce unnecessary waste of time in the preprocessing and provide high-precision data support for the application of UAV hyperspectral *** this study,the geometric correction accuracy under various geometric correction models(including affine transformation model,local triangulation model,polynomial model,direct linear transformation model,and rational function model)and resampling methods(including nearest neighbor resampling method,bilinear interpolation resampling method,and cubic convolution resampling method)were ***,the distribution,number,and accuracy of control points were analyzed based on the control variable method,and precise ground control points(GCPs)were *** results showed that the average geometric positioning error of UAV hyperspectral images(at 80 m altitude AGL)without geometric correction was as high as 3.4041 m(about 65 pixels).The optimal geometric correction model and parameter combination of the UAV hyperspectral image(at 80 m altitude AGL)used a local triangulation model,adopted a bilinear interpolation resampling method,and selected 12 edgemiddle distributed *** correction accuracy could reach 0.0493 m(less than one pixel).This study provides a reference for the geometric correction of UAV hyperspectral images.

关键词： geometric correction hyperspectral images unmanned aerial vehicle(UAV) ground control point(GCP)

A convolutional neural network to detect possible hidden data in spatial domain images

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Cybersecurity 2024年第1期7卷 37-52页

作者： Jean De la Croix Ntivuguruzwa Tohari Ahmad Department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African Center of Excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the ***,attackers with a steganalysis technique may break *** steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of Convolutional Neural Network(CNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based *** the existing CNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training *** research proposes a new method with a CNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain *** proposed method comprises three phases:pre-processing,feature extraction,and ***,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax *** results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis Deep learning Convolutional neural network Infrastructure

Design and optimization of an airflow-vibration sieving device for the effective cleaning of cyperus esculentus *** mixture

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 77-88页

作者： Shan Chen Shiguan An za Kan Lidong Huang Hewei Meng Jiangtao Qi Huijie Peng College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina Engineering Research Center for Production Mechanization of Oasis Special Economic Crop Ministry of EducationShihezi 832000XinjiangChina Guilin Mike Machinery Co. LtdGuilin 541000GuangxiChina

The threshing mixture of Cyperus esculentus(Tiger nut)planted in sandy areas is complex during harvesting,and there are problems of high impurity rate and high cleaning loss rate of the *** this paper,the threshing mixture of Cyperus esculentus is taken as the research object,and the suspension speed of each component is measured to design an“airflow+vibration”sieving *** the vector polygon method to explore the law of motion of the vibrating sieve,establish the force model of the seeds on the sieve surface,and analyze the conditions for the seeds to penetrate the *** to the principle of seeds penetrating the sieve and long stalks not penetrating the sieve,the geometric model of sieve blades opening degree adjustment mechanism is *** of the conditions under which long stalks can be thrown out of the *** experiment bench of the cleaning device was built,and the evaluation indexes were the rate of seed impurity and the rate of cleaning loss of the device,and the crank speed,sieve blades opening degree and fan speed were used as the experiment factors to study the influence law of each influencing factor on the evaluation index through single-factor *** response surface methodology to find the optimal combination of working parameters of the cleaning *** verify the device’s application on the combine harvester to improve the effectiveness of the cleaning operation of the Cyperus esculentus combine harvester.

关键词： sand cultivation Cyperus esculentus wind sieve type cleaning device optimization

ZnSb/Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction for flexible near-infrared photodetector arrays

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Journal of Semiconductors 2024年第5期45卷 99-105页

作者： Chuqiao Hu Ruiqing Chai Zhongming Wei la Li Guozhen Shen State Key laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronic Engineering University of Chinese Academy of SciencesBeijing 100049China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China

Two-dimension(2D)van der Waals heterojunction holds essential promise in achieving high-performance flexible near-infrared(NIR)***,we report the successful fabrication of ZnSb/Ti_(3)C_(2)T_(x)MXene based flexible NIR photodetector array via a facile photolithography *** single ZnSb/Ti_(3)C_(2)T_(x)photodetector exhibited a high light-to-dark current ratio of 4.98,fast response/recovery time(2.5/1.3 s)and excellent stability due to the tight connection between 2D ZnSb nanoplates and 2D Ti_(3)C_(2)T_(x)MXene nanoflakes,and the formed 2D van der Waals *** polyethylene terephthalate(PET)substrate enables the ZnSb/Ti_(3)C_(2)T_(x)photodetector withstand bending such that stable photoelectrical properties with non-obvious change were maintained over 5000 bending ***,the ZnSb/Ti_(3)C_(2)T_(x)photodetectors were integrated into a 26×5 device array,realizing a NIR image sensing application.

关键词： ZnSb nanoplates Ti_(3)C_(2)T_(x)MXene van der Waals heterojunction flexible photodetector image sensing

Benefits of jejunostomy feeding in patients who underwent gastrectomy for cancer treatment

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2461-2473页

作者： Romain Jaquet Emmanuel Rivkine Nicole De souza Jean Roudié Department of Digestive and Visceral Surgery Nord Essonne Hospital Group-Longjumeau SiteLongjumeau 91160France Department of General and Digestive Surgery Pierre Zobda-Quitman HospitalUniversity Hospital CenterMartiniqueFranceFort de France 97261Martinique

BACKGROUND Gastric cancer is associated with significant undernutrition responsible for an increase in morbidity and mortality after *** To evaluate the impact of enteral nutrition by jejunostomy feeding in patients undergoing gastrectomy for *** Between 2003 and 2017,all patients undergoing gastrectomy for cancer treatment were included retrospectively.A group with jejunostomy(J+group)and a group without jejunostomy(J-group)were *** Of the 172 patients included,60 received ***,the two groups were comparable with respect to the nutritional parameters studied(body mass index,albumin,etc.).In the postoperative period,the J+group lost less weight and albumin:5.74±8.4 vs 9.86±7.5 kg(P=0.07)and 7.2±5.6 vs 14.7±12.7 g/L(P=0.16),*** morbidity was 25%in the J+group and 36.6%in the J-group(P=0.12).The J+group had fewer respiratory,infectious,and grade 3 complications:0%vs 5.4%(P=0.09),1.2%vs 9.3%(P=0.03),and 0%vs 4.7%(P=0.05),*** 30-day mortality was 6.7%in the J+group and 6.3%in the J-group(P=0.91).CONclUSION Jejunostomy feeding after gastrectomy improves nutritional characteristics and decreases postoperative morbidity.A prospective study could confirm our results.

关键词： Feeding jejunostomy Gastric cancer Undernutrition Morbimortality Survival

Tri-axial accelerometry allows to determine parental food provisioning behaviour in a marine bird

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Avian Research 2024年第3期15卷 345-351页

作者： Monserrat Del caño Flavio Quintana Giacomo Dell’Omo Agustina Gómez-laich Instituto de Biología de Organismos Marinos(IBIOMAR) CONICETBoulevard Brown 2915U9120ACDPuerto MadrynChubutArgentina Ornis Italica Piazza Crati 1500199RomeItaly Departamento de Ecología Genética y Evolución(EGE)and Instituto de EcologíaGenética y Evolución de Buenos Aires(IEGEBA)CONICETFacultad de CienciasExactas y NaturalesUniversidad de Buenos AiresPabellón II Ciudad UniversitariaC1428EGACiudad Autónoma de Buenos AiresArgentina

The study of parental food provisioning is essential for understanding the breeding ecology of *** conducted the first study using accelerometry to detect food provisioning in birds,using Support Vector Machine(SVM)models to identify when adults feed chicks of three different age *** were attached to the head of adult female Imperial Shags(Leucocarbo atriceps),and various attributes derived from the acceleration signals were used to train SVM models for each chick age *** performance improved with chick age class,with SVM models achieving high overall accuracy(>88%)and highest sensitivity in older chick categories(>91%).However,precision values,especially for younger chicks,remained relatively low(between 26%and 45%).The application of a time filter based on the minimum duration of the observed food provisioning behaviours for each chick age category,improved model performance by reducing false provisioning behaviours,particularly in the model for older chicks,which showed the highest precision(72.4%).This study highlights the effectiveness of accelerometry and machine learning in studying parental food provisioning in birds,providing a rapid and accurate data collection method to complement traditional *** described methodology can be applied to any bird species that exhibits distinctive movements while feeding its offspring and has suitable characteristics for attaching an accelerometer to the body part that best captures this ***,it is hoped that the results of this study will contribute to future research on key questions in parental investment theory and reproductive strategies in birds.

关键词： Accelerometry Food provisioning Imperial shag Leucocarbo atriceps Seabird Support vector machine

High Seebeck Coefficient Thermally Chargeable Supercapacitor with Synergistic Effect of Multichannel Ionogel Electrolyte and Ti_(3)C_(2)T_(x)MXene-Based Composite Electrode

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Energy & Environmental Materials 2024年第6期7卷 367-377页

作者： Zhongming Chen Zhijian Du la Li Kai Jiang Di Chen Guozhen Shen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China Faculty of Hepato-Pancreato-Biliary Surgery Chinese PLA General HospitalInstitute of Hepatobiliary Surgery of Chinese PLA&Key Laboratory of Digital Hepetobiliary SurgeryChinese PLABeijing 100853China

Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable ***,the low Seebeck coefficient and heat-to-electricity conversion efficiency hinder further *** this paper,we designed a high-performance thermally chargeable supercapacitor device composed of ZnMn_(2)O_(4)@Ti_(3)C_(2)T_(x)MXene composites(ZMO@Ti_(3)C_(2)T_(x)MXene)electrode and UIO-66 metal–organic framework doped multichannel polyvinylidene fluoridehexafluoro-propylene ionogel electrolyte,which realized the thermoelectric conversion and electrical energy storage at the same *** thermally chargeable supercapacitor device exhibited a high Seebeck coefficient of 55.4 mV K^(−1),thermal voltage of 243 mV,and outstanding heat-to-electricity conversion efficiency of up to 6.48%at the temperature difference of 4.4 *** addition,this device showed excellent charge–discharge cycling stability at high-temperature differences(3 K)and low-temperature differences(1 K),*** two thermally chargeable supercapacitor units in series,the generated output voltage of 500 mV further confirmed the stability of *** a single device was worn on the arm,a thermal voltage of 208.3 mV was obtained indicating the possibility of application in wearable electronics.

关键词： ionogel electrode Soret effect thermally chargeable supercapacitor Ti_(3)C_(2)T_(x)MXene UIO-66 MOF

The Influence of Significant Public Health Events on Offline Consumption and Its Pathways

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 627-648页

作者： Baile Lu Kewei Zhou Shuai Hao la Ta Hongyan Dai Weihua Zhou College of Systems Engineering National University of Defense TechnologyChangsha 410073China Business School Central University of Finance and EconomicsBeijing 100081China Department of Marketing and Operations Management College of BusinessSouthern University of Science and TechnologyShenzhen 518055China School of Management Zhejiang UniversityHangzhou 310058China

In the face of a significant public health event,consumers may either increase their panic buying or decrease their willingness to make *** study focuses on the impact of a significant public health event on offline store sales and consumer consumption,utilizing data from chain convenience stores in Hefei and Wuhu during early 2019 and early 2020 in *** a difference-in-differences model,the study investigates the effect of the significant public health event outbreak on weekly store sales,order numbers,and consumer consumption in terms of product quantities,transaction amount,average amount per order,and transaction *** from prior literature that finds hoarding behavior of consumers online,the findings of this paper indicate a significant reduction in stores’offline weekly sales and order numbers,as well as consumers’offline weekly consumption across the four dimensions,as a result of the significant public health event ***,employing a mediation model,the study explores the pathway of population mobility through which the significant public health event adversely affects offline ***,subset analysis is conducted for stores located in different areas and consumers with varying characteristics,revealing that the aforementioned conclusions predominantly apply to stores situated in office areas and residential areas,as well as consumers with either no apparent preference for different product categories or a noticeable preference for food.

关键词： Significant public health event offline consumption population mobility mediating effect

Pollen analysis reveals the effects of uncovered interactions,pollen-carrying structures,and pollinator sex on the structure of wild bee-plant networks

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Insect Science 2024年第3期31卷 971-988页

作者： clément Tourbez carmelo Gómez-Martínez MiguelÁngel Gonzalez-Estévez Amparo lazaro Mediterranean Institute for Advanced Studies(UIB-CSIC) Global Change Research GroupEsporlesBalearic IslandsSpain Department of Biology Ecology AreaUniversity of the Balearic/slandsPalmaSpain

Pollination networks are increasingly used to model the complexity of interactions between pollinators and flowering plants in *** methods exist to sample these interactions,with direct observations of plant-pollinator contacts in the field being by far the most *** the identification of pollen carried by pollinators allows uncovering interactions and increasing sample sizes,the methods used to build pollen-transport networks are variable and their effect on network structure remains *** understand how interaction sampling influences the structure of networks,we analyzed the pollen found on wild bees from eight communities across Mallorca Island and investigated the differences in pollen loads between bee body parts(scopa ***)and *** then assessed how these differences,as well as the uncovered interactions not detected in the field,influenced the structure of wild bee-plant *** identified a higher quantity and diversity of pollen in the scopa than in the rest of the female body,but these differences did not lead to differences in structure between plant-pollination(excluding scopa pollen)and bee-feeding interaction(including scopa pollen)***,networks built with pollen data were richer in plant species and interactions and showed lower modularity and specialization(H2'),and higher nestedness than visitation networks based on field *** interactions with plants were stronger compared to those of males,although not ***,females were more generalist(low d')and tended to be more central in interaction networks,indicating their more key role structuring pollination networks in comparison to *** study highlights the importance of palynological data to increase the resolution of networks,as well as to understand important ecological questions such as the differences between plant-pollination and bee-feeding interaction networks,and the role of sexes in pollination.

关键词： palynology pollen-transport networks pollination role of bee sexes sampling methodology visitation networks