Intelligent field monitoring system for cruciferous vegetable pests using yellow sticky board images and an improved Cascade R-CNN

Cruciferous vegetables are important edible vegetable crops.However,they are susceptible to various pests during their growth process,which requires real-time and accurate monitoring of these pests for pest forecasting and scientific control.Hanging yellow sticky boards is a common way to monitor and trap those pests which are attracted to the yellow color.To achieve real-time,low-cost,intelligent monitoring of these vegetable pests on the boards,we established an intelligent monitoring system consisting of a smart camera,a web platform and a pest detection algorithm deployed on a server.After the operator sets the monitoring preset points and shooting time of the camera on the system platform,the camera in the field can automatically collect images of multiple yellow sticky boards at fixed places and times every day.The pests trapped on the yellow sticky boards in vegetable fields,Plutella xylostella,Phyllotreta striolata and flies,are very small and susceptible to deterioration and breakage,which increases the difficulty of model detection.To solve the problem of poor recognition due to the small size and breaking of the pest bodies,we propose an intelligent pest detection algorithm based on an improved Cascade R-CNN model for three important cruciferous crop pests.The algorithm uses an overlapping sliding window method,an improved Res2Net network as the backbone network,and a recursive feature pyramid network as the neck network.The results of field tests show that the algorithm achieves good detection results for the three target pests on the yellow sticky board images,with precision levels of 96.5,92.2 and 75.0%,and recall levels of 96.6,93.1 and 74.7%,respectively,and an F_(1) value of 0.880.Compared with other algorithms,our algorithm has a significant advantage in its ability to detect small target pests.To accurately obtain the data for the newly added pests each day,a two-stage pest matching algorithm was proposed.The algorithm performed well and achieved results that were highly consistent with manual counting,with a mean error of only 2.2%.This intelligent monitoring system realizes precision,good visualization,and intelligent vegetable pest monitoring,which is of great significance as it provides an effective pest prevention and control option for farmers.

Effects of increased seeding density on seedling characteristics,mechanical transplantation quality,and yields of rice with crop straw boards for seedling cultivation

The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.

Experimental and numerical study regarding H-steel all-bolted connection steel frame with composite wall boards

H-steel all-bolted connection steel frame structures with heat preservation and decoration composite wall boards were investigated and the seismic performances of three scaled specimens were studied.The failure modes,hysteresis curves,bearing capacity,ductility,energy dissipation capacity,stiffness degradation and strain distribution were discussed.The calculation method of structural theoretical internal force was presented.The results showed that the overall structural seismic performance was better,and the structural ductility met the demands of elastic-plastic inter-story drift angle for seismic design.The H-steel weak-axis connection structure obtained better energy dissipation capacity,and its bearing capacity and stiffness were slightly different from the strong-axis connection.The heat preservation and decoration performance of composite wallboard and the all-bolted connection of the steel frame realized prefabrication during the whole construction period.The plastic hinge of the steel beam can be moved outwards because of the L-angles,which effectively avoids stress concentration in joint areas and expands the plastic hinge range.The errors between the theoretical structural capacity calculated by the plastic analysis method and the test results were within 2.44%.In addition,structural failure mechanisms and bearing capacities were verified by the finite element(FE)analysis,and the effects of the main parameters on the structures were investigated.The FE verification results were the same as in the test.The research results provide theoretical support and technical guidance for the application of thermal insulation and decorative composite wall panels in H-shaped steel all-bolted steel frames.

Distribution behavior of valuable elements in oxygen-enriched top-blown smelting process of waste printed circuit boards

Oxygen-enriched top-blown smelting is a promising technology for processing waste printed circuit boards(WPCBs).The distribution behavior of valuable elements in WPCBs during smelting was investigated by varying the oxygen-enriched concentration,oxygen volume,CaO/SiO_(2)(mass ratio),and Fe/SiO_(2)(mass ratio).The optimal operating conditions were obtained by implementing a one-factor-at-a-time method.X-ray diffractometer,scanning electron microscopy−energy dispersive spectrometer,and inductive coupled plasma-atomic emission spectroscopy methods were utilized to detect the chemical composition,occurrence state as well as elemental contents of alloy and slag.It is found that the elements of Cu,Sn and Ni are mainly accumulated in the alloy while Fe is mainly oxidized into the slag.The direct yields of Cu,Sn and Ni are 90.18%,85.32%and 81.10%under the optimal conditions of temperature 1250℃,oxygen-enriched concentration 30%,oxygen volume 24 L,CaO/SiO_(2) mass ratio 0.55,and Fe/SiO_(2) mass ratio 1.05.The results show that the valuable metals are mainly lost in the slag through mechanical entrainment.

Effect of copper content on the pyrolysis process of organic components in waste printed circuit boards:Based on experimental and quantum chemical DFT simulations

In recent years,scientists have become increasingly concerned in recycling electronic trash,particularly waste printed circuit boards(WPCBs).Previous research has indicated that the presence of Cu impacts the pyrolysis of WPCBs.However,there may be errors in the experimental results,as printed circuit boards(PCBs)with copper and those without copper are produced differently.For this experiment,we blended copper powder with PCB nonmetallic resin powder in various ratios to create the samples.The apparent kinetics and pyrolysis properties of four resin powders with varying copper concentrations were compared using nonisothermal thermogravimetric analysis(TG)and thermal pyrolysis-gas chromatography mass spectrometry(Py-GC/MS).From the perspective of kinetics,the apparent activation energy of the resin powder in the pyrolysis reaction shows a rise(0.1<a<0.2)-stable(0.2<a<0.4)-accelerated increase(0.4<a<0.8)-decrease(0.8<a<0.9)process.After adding copper powder,the apparent activation energy changes more obviously when(0.2<a<0.4).In the early stage of the pyrolysis reaction(0.1<a<0.6),the apparent activation energy is reduced,but when a?0.8,it is much higher than that of the resin sample without copper.Additionally,it is discovered using thermogravimetric analysis and Py-GC/MS that copper shortens the temperature range of the primary pyrolysis reaction and prevents the creation of compounds containing bromine.This inhibition will raise the temperature at which compounds containing bromine first form,and it will keep rising as the copper level rises.The majority of the circuit board molecules have lower bond energies when copper is present,according to calculations performed using the Gaussian09 software,which promotes the pyrolysis reaction.

Effect of Low pH on Forming Process of Desulfurization Gypsum Composite Boards Strengthened by Melamine-formaldehyde Resin

Through exploring the effects of low pH on the composite system of desulfurization gypsum(DG)enhanced by melamine-formaldehyde resin(MF),it is found that the inducing of sulfate-ion,in contrast to chloride and oxalate ions,favors the longitudinal growth of the crystalline form of the hydration product,which was relatively simple and had the highest length to width(L/D)ratio.At the same time,MF can also improve L/D ratio of gypsum hydration products,which favors the formation of hydrated whiskers.Finally,in a composite system composed of hemihydrate gypsum,MF,and glass fibers,when dilute sulfuric acid was used to regulate pH=3-4,the tight binding formed among the components of the composite system compared to pH=5-6.The hydration product of gypsum adheres tightly to glass fiber surface and produces a good cross-linking and binding effect with MF.The flexural strength,compressive strength,elastic modulus,and water absorption of the desulphurized gypsum composite board is 22.7 MPa,39.8 MPa,5608 MPa,and 1.8%,respectively.

Protective benefits of HDPE board sand fences in an environment with variable wind directions on Gobi surfaces:wind tunnel study

The Golmud-Korla Railway in the Gobi area faces operational challenges due to sand hazards,caused by strong and variable winds.This study addresses these challenges by conducting wind tunnel tests to evaluate the protective benefits of High Density Polyethylene(HDPE)board sand fences,focusing on their orientation relative to various wind directions(referred to as'wind angle').This study found that the size of the low-velocity zone on the leeward side of the sand fences(LSF)expanded with an increase in the wind angle(WA).At 1H(the height of the sand fence)and 2H positions on the LSF,the wind speed profiles(WSP)exhibited a segmented logarithmic growth,constrained by Z=H at varying WAs.The efficacy of the sand fence in obstructing airflow escalated as WA increased.The size of the WA has a significant impact on the protective efficiency of HDPE board sand fences.Furthermore,compared to typical sandy surfaces,the rate of sand transport across the Gobi surface diminishes more slowly with height,attributed to the gravel's rebound effect.This phenomenon allows some sand particles to bypass the fences,rendering them less effective at blocking wind and trapping sand than in sandy environments.This paper offers scientific evidence supporting the practical use and enhancement of HDPE board sand fences in varied wind conditions.

Protective benefit of folded linear HDPE board sand fences along the Golmud-Korla Railway,China:Field observation and wind tunnel study

The Milan Gobi area of the Golmud-Korla Railway in northwest China is located in the lower dispersal area of the mountain pass and has strong winds with evident double wind direction characteristics.This study introduced a novel sand fence deployment technique,termed‘folded linear deployment',designed to position the sand fence orthogonally to the two predominant wind directions for optimal protection.This study used wind tunnel and field tests to evaluate the wind and sand flow characteristics,as well as the windproof and sandresistant performance of folded linear HDPE(Highdensity polyethylene)board sand fences.The results suggest that the airflow around the fence creates clear zoning characteristics.The deceleration area on the BSF(backwind side of the sand fence)is much larger than that on the DSF(downwind side of the sand fence).Thus,sand particles are primarily deposited on the BSF.At different wind speeds,the airflow at 2 and 5 h on the DSF is not disturbed.The WSP(wind speed profile)presents a logarithmic distribution.The airflow is disturbed at 1-20 h on the BSF,and the WSP gradually deviates from the logarithmic law.However,as the airflow moves away from the fence,the WSP gradually approaches a logarithmic distribution.Meanwhile,the WPE(windproof efficiency)and SRE(sand-resistant efficiency)of the sand fence exceed 80%.In addition,the results of wind tunnel tests are compared with those of field tests.The overall dispersion is good,and the best dispersion is found at z/H=2.00,indicating good agreement between the two test results.This study provides a scientific basis for the design of sand hazard control measures,similar to the railway project in the Gobi Gale area.

Mechanism properties of a bird-neck bionic rigid-flexible structure

By the biological construction of a bird neck,a bionic bird-neck multilevel rigid-flexible structure is proposed and some biometric properties are explained.The proposed structure can flexibly deform in six directions,which inspires the study of its mechanical properties for flexible deformations.First,the structural configuration and composition are determined based on the study of the anatomical characteristics of the woodpeckers.Since the skeletons and muscles have very different values for the elasticity modulus and the deformation is mostly dependent on the muscle tension,the bionic structure consists of rigid units and bio-syncretic components.For combined deformations,the mechanical model is established by the connectivity matrix to describe the connection of each level.Second,based on the principle of minimum potential energy,an integral form-finding method is proposed for flexible combination deformations.All of the integral forms obtained with the theoretical analysis are compared with the results with Finite Element Analysis.The structural parameters of the bionic structure were then tightly fixed to the actual shape of the bird’s neck and the corresponding overall form took on an"S"shape,which perfectly matched the construction of the bird’s neck.In addition,for the pre-deformation form,by analyzing the potential energy of the bionic structure,due to the adjustable dynamic stiffness property,an explanation is provided for the significant dynamic stability of the bird neck in bending.This study not only proposes a bionic rigid-flexible structure with high spatial accessibility but also explains biological properties of a bird neck based on the study of its mechanics characteristics.Based on the modeling and the mechanical properties of the bionic structure in flexible spatial combination deformations,the multi-steady state,and the variable dynamic stiffness,the bird-neck bionic rigid-flexible structure has significant applications such as aeronautical deployable systems,manipulator positioning,and dynamic stability fields.

A Single-Board Integrated Millimeter-Wave Asymmetric Full-Digital Beamforming Array for B5G/6G Applications

In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)communications.The proposed integrated array effectively addresses the challenge of arranging a large number of ports in a full-digital array by designing vertical connections in a three-dimensional space and successfully integrating full-digital transmitting(Tx)and receiving(Rx)arrays independently in a single board.Unlike the traditional symmetric array,the proposed asymmetric array is composed of an 8×8 Tx array arranged in a square shape and an 8+8 Rx array arranged in an L shape.The center-to-center distance between two adjacent elements is 0.54k0 for both the Tx and Rx arrays,where k0 is the free-space wavelength at 27 GHz.The proposed AFDBF array possesses a more compact structure and lower system hardware cost and power consumption compared with conventional brick-type full-digital arrays.In addition,the energy efficiency of the proposed AFDBF array outperforms that of a hybrid beamforming array.The measurement results indicate that the operating frequency band of the proposed array is 24.25–29.50 GHz.An eight-element linear array within the Tx array can achieve a scanning angle ranging from-47°to+47°in both the azimuth and the elevation planes,and the measured scanning range of each eight-element Rx array is–45°to+45°.The measured maximum effective isotropic radiated power(EIRP)of the eight-element Tx array is 43.2 dBm at 28.0 GHz(considering the saturation point).Furthermore,the measured error vector magnitude(EVM)is less than 3%when 64-quadrature amplitude modulation(QAM)waveforms are used.

A systematic review of rigid-flexible composite pavement

Rigid-flexible composite pavement has gained significant popularity in recent decades.This paper provides a comprehensive review of the research progress concerning rigid-flexible composite pavement,aiming to promote its application and address key issues while identifying future directions.The design theory and methodology of rigid-flexible composite pavement are discussed,followed by a description of its structural and mechanical behavior characteristics.The load stress,temperature stress,and their interactive effects between the asphalt layer and the rigid base were analyzed.It is clarified that the asphalt layer serves a dual role as both a“functional layer”and a“structural layer”.Typical distresses of rigid-flexible composite pavement,which primarily occur in the asphalt layer,were discussed.These distresses include reflective cracking,top-down cracking,rutting,and compressive-shear failure.Generally,the integrity of the rigid base and the interlaminar bonding conditions significantly impact the performance and distress of the asphalt layer.The technology for enhancing the performance of rigid-flexible composite pavement is summarized in three aspects:asphalt layer properties,rigid base integrity,and interlaminar bonding condition.The study concludes that developing high-performance pavement materials based on their structural behaviors is an effective approach to improve the performance and durability of rigid-flexible composite pavement.The integrated design of structure and materials represents the future direction of road design.

Women on Boards of Directors

This research aims to measure the current gender representation in membership of boards of directors,and to study the factors affecting the presence of women on boards.The results of the study will support the decision makers and policy makers at all levels by providing knowledge that contributes to bridging the current gap in participation of women boards.The methodology used in this research is the descriptive analytical approach,which relies on quantitative methods in the process of collecting and analyzing data.This study represents the boards of directors in the three sectors(public,private,and non-profit)in the Kingdom of Saudi Arabia,The study sample contained 350 targets,where a random sample of 150 people in the public sector,100 people in the private sector,and 100 people in the non-profit sector were selected.The research result found that the majority of the responses believe that the lack of experience and training,and social factors,are the most impact areas of explaining the reasons for the existence of a gap in women’s membership in boards of directors in the three sectors.And the most important reasons for the existence of a gender gap in board membership are:there is no statutory minimum percentage for women’s representation on boards of directors,and scarcity of female competencies in general,and the lack of women occupying leadership positions.

BOB(Bosa On Board)设计研究

采用bosa on board的方式,将光通信电路直接铺设在PCB板上,替代传统的光模块独立器件,实现GPON/EPON产品的低成本高性能。

Development and Characterization of Particle Boards Based on Sorghum Husk

This study tackles current environmental challenges by developing innovative and eco-friendly particle boards utilizing sorghum husk, combined with recycled expanded polystyrene (EPS). This dual eco-responsible approach valorizes sorghum husk, often deemed agricultural waste, and repurposes EPS, a plastic waste, thus contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene within a solvent to create a binder, which is then mixed with sorghum husk and cold-pressed into composite boards. The study explores the impact of two particle sizes (fine and coarse) and two different concentrations of the recycled EPS binder. Results demonstrate significant variations in the boards’ mechanical properties, displaying a range of Modulus of Rupture (MOR) from 0.84 MPa to 3.85 MPa, and Modulus of Elasticity (MOE) spanning from 658.13 MPa to 1313.25 MPa, influenced by the binder concentration and particle size. These characteristics suggest that the boards can be effectively used in various construction applications, including interior decoration, false ceilings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only exemplifies the valorization of plastic and agricultural wastes but also offers a practical, localized solution to global climate change challenges by promoting sustainable construction materials.

Dynamic response of high-speed railway vehicle and welded turnout on large-span bridges based on rigid-flexible coupling system

Welded Turnout on Large-span Bridge(WTLB)is a complex multi-layer heterogeneous system and can significantly influence the service performance of High-Speed Railway(HSR).Understanding the coupling dynamic response of the vehicle and WTLB is essential.Previous research did not consider the dynamic behavior of foundations,leading to an underestimation of the vehicle-turnout-foundation coupling dynamic response,particularly when turnouts were laid on large-span bridges.This study proposes a novel modeling method that includes the foundations,to overcome the previous shortcomings by applying a rigid-flexible coupling system.In this approach,the vehicle was modeled as a rigid body sub-model in a Multi-Body Software(MBS),while WTLB was modeled as a flexible bodies sub-model using Finite Element(FE)software.The modal information from the FE model was imported into the MBS software.The two sub-models were coupled by the wheel-rail contact in the MBS environment and then the Vehicle-turnout-bridge Rigid-flexible Coupling Dynamic(VRCD)calculation model was established and it was discovered that the calculation results showed good agreement with the field test data.Through the VRCD model,the safety of the structure,the stability of the vehicle and the comfort of passengers were investigated,as well as several important infrastructure factors.The results demonstrate that this novel method provides accurate calculations and highlights the complex and significant interactions in the vehicle-turnout-bridge system.

分割董事席位的上市公司股东协议问题研究

我国境内上市公司版本的“湖畔合伙人”协议约定董事席位提名权的股东协议,已成为一种A股上市公司控制权结构的新形式。本文针对其三方面问题展开研究:特征方面,A股上市公司协议类型上以横向协议为主、场景上以控制权变更为主、主体上以控制权变更前后“双控人”为主、内容上以董事会安排为主;效力方面,以上市公司董事席位分割条款为例,本文为股东协议提供了一个具有普适性的法律效力分析框架,由合同效力、组织法效力和事后可履行性三个阶层构成;监管方面,本文认为上市公司董事席位分割条款不应作为一致行动人或共同控制人的单一认定标准。

农村集体经济组织法人治理结构解释论

为保障《农村集体经济组织法》实施,亟须从解释论探讨农村集体经济组织法人的治理结构。对此,立法确立了“权力机构(成员大会)—执行机构(理事会)—监督机构(监事会)”的基本框架。从权力机构看,成员权具有强烈的身份性特征,无法以投资取得;成员大会的决议不应均采取绝大多数决,否则会导致决议难以形成,应允许章程对一般事项和重大事项进行区分,前者采取多数决,后者采取绝大多数决。同时,要警惕出现成员代表大会绕过成员大会表决的情景。从执行机构看,对理事长或理事的选任,不应以成员为限;理事会表决并非一定要采取多数决,意味着总人数不限于单数。从监督机构看,关于监事会或监事的设置规定应理解为倡导性规范,而非必须强制设立监事会或监事,设置权限宜交由章程规定,且监事的选任应不受成员身份的限制。农村集体经济组织法人治理结构的选择,应考量不同地区农村集体经济的发展状况,而非采用单一的治理图景。

环保隔热泡沫板裁切机的应用研究

新型环保隔热材料的出现可有效提高建筑物的保温性能,从而减少建筑物的能耗,更加节能环保。针对环保隔热泡沫板的裁切过程,分析了人工裁切的缺陷和自动裁切设备的现状。在分析现有裁切工艺的基础上对环保隔热泡沫板裁切机进行了整体设计和创新设计,可以实现切断、切槽的自动化,同时实现自动纠偏,大大提高了生产效率。裁切机在企业试用效果良好,操作简单方便,运行稳定可靠,具有良好的推广应用前景。

乡村振兴背景下县域小学寄宿制教育:成效、挑战与发展--基于内蒙古A县的案例研究

在众多教育模式中,寄宿制教育因其独特的育人环境和教育形式,对改善乡村教育资源短缺、优化教育生态具有重要意义。探讨乡村振兴战略背景下县域小学寄宿制教育的运行现状、面临的挑战及未来的发展路径,为优化乡村教育体系提供借鉴,这不仅是深化教育改革的需要,也是全面推进乡村振兴的必然要求。

论我国法定机构设立的法治困境、逻辑起点与建构路径

法定机构作为一种新型社会治理模式,被引入我国并在各地开发区等特殊功能区试点。通过对实践检视发现,我国法定机构的设立并不规范,其性质定位不明导致设立的逻辑混乱。应将法定机构定性为特殊的授权组织,以承担政府部门或现有其他机构无法有效履行的政、事、企一体化职能为其基本定位。设立法定机构首先应明确我国法定机构的功能定位、适法的设立依据以及设立所遵循的原则,并在此基础上,从立法、组建、授权等具体环节建构完善我国法定机构的设立制度,从而规范其设立。