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Occupational Diseases and Environmental Medicine 2024年第2期12卷 142-159页

作者： Adjobimey Mênonli Mikponhoué Rose Dégbey Cyriaque Hountohotègbé Esdras Guédou Alexandre Lawani Affousath Ayélo Paul Hinson Antoine Unité de Recherche et d&#8217Enseignement en Sant&#233 au Travail et Environnement FSS Cotonou Benin Service de Santé au Travail du Centre National Hospitalier Universitaire de Pneumo-Phtisiologie Cotonou Benin Occupational Health Service at the Referral Hospital Construction site Abomey-Calavi Benin Inter-Faculty Center for Environmental Training and Research for Sustainable Development (CIFRED) Abomey-Calavi Benin

Introduction: Work-related accidents are frequent and serious in the construction sector. The aim of the study was to determine the frequency and factors associated with occupational accidents on the construction site of a referral hospital in Benin. Methods: A cross-sectional study was carried out. The sample size was calculated using the Schwartz form adjusted for the number of workers on site and was 129 workers. Random sampling was used. The dependent variable was work-related accidents. The other variables were socio-demographic and occupational characteristics. Data were collected through a questionnaire survey. Medians and proportions were calculated. An association was sought using Chi-square and Fisher tests with a threshold of p Results: A total of 132 workers were included. Their median age was 30 years with an ITQ of [27 - 38];men were the most represented 126 (95.45%) with a level of education higher than or equal to high school in 101 (76.52%) and in the majority with a permanent status 85 (64.39%). Seniority of more than 5 years was observed in 92 (69.7%). Workers working more than 8 hours of overtime per week numbered 57 (43.18%). Exposure to vibrating objects was 49 (37.12%). In terms of psychosocial constraints, 82.58% had high psychological demands;79.53% low decision-making latitude;50.76% low social support. The frequency of work-related accidents was 6.82%, and the only associated factor was the type of worker (p = 0.016). On the other hand, there were 10.2% accidents among workers handling vibrating objects versus 4.98% among those not using them. With regard to psychosocial constraints, the following frequencies were recorded respectively: 6.42% among those with high psychological demand versus 8.7% among those with low psychological demand;7.62% among those with low decision-making latitude versus 3.7% among those with high decision-making latitude;8.96% among those with low social support versus 4.62% among those with high support. Conclusi

关键词： Occupational Injury Building and Civil Engineering Construction Environment

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On Sliding Friction of PEEK Based Composite Coatings

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材料热处理学报 2004年第05B期25卷 1175-1179页

作者： C. Mateus C. Coddet LERMPS - UTBM (site de Sevenans) 90 010 Belfort Cedex FranceLERMPS - UTBM (Site de Sevenans) 90 010 Belfort Cedex France

Polyetheretherketone (PEEK) based composite materials become of great interest to applications as bearing and slider materials due to their excellent tribological performance. In present work, graphite and MoS2 (7%, wt) filled PEEK coatings were prepared using serigraph technique. Employing a uniform design experiment, the friction behavior of the composite coatings was systematically investigated under dry sliding conditions on a ball-on-disc arrangement. The evolution mechanism of coating friction coefficient was discussed. Correlation of coatings friction coefficient with sliding velocity and applied load was accomplished using stepwise regression method. The results indicate that friction coefficients of PEEK + MoS2 and PEEK + graphite coating decrease while increasing applied load. Moreover, friction coefficient of PEEK + MoS2 coating increases with increasing sliding velocity.

关键词： PEEK 滑动摩擦混合涂层聚醚醚酮累积概率逐步回归

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High resolution catalog of the Luxian(Sichuan,China)M_(S)6.0 earthquake sequence and analysis of the seismogenic structures

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Earthquake Science 2025年第1期38卷 33-46页

作者： Huili Guo Dahu Li Pingping Wu Qiyan Yang Ningbo Jiang Mi Gao Zhifeng Ding Institute of Geophysics China Earthquake AdministrationBeijing 100081China Chengdu Institute of the Tibetan Plateau Earthquake Research China Earthquake Administration(Chengdu Base of China Seismic Experimental Site)Chengdu 610041China Sichuan Earthquake Agency Chengdu 610041China Key Laboratory of Intelligent Detection and Equipment for Underground Space of Beijing-Tianjin-Hebei Hebei GEO UniversityShijiazhuang 050031China

The epicenter of the Luxian M_(S)6.0 earthquake on September 16,2021,was located in the southern Sichuan Basin,which is a historically seismically quiescent *** recent years,the frequency of earthquakes has increased with the large-scale exploitation of shale *** evident surface fractures or seismic faults were observed after the Luxian *** on high-quality data recorded by a dense seismic array composed of 70 portable stations with an average spacing of 2-3 km,a highresolution seismic catalog was constructed for 7 days before and 36 days after the M_(S)6.0 earthquake using LOC-FLOW,an effective workflow of phase picking,phase association,and earthquake *** on the new earthquake catalog,four earthquake clusters that occurred within the Yujiasi Syncline during this period were *** them,the M_(S)6.0 main earthquake sequence had a NW-SE trend and inclined towards the SW,with a length of approximately 8 km and width of 5 *** M_(S)6.0 earthquake sequence only appeared after the *** other three clusters were located in the northeast direction of the M_(S)6.0 earthquake sequence,all of which were NE-SW trending strips and had no evident direct correlation with the M_(S)6.0 *** focal depth was concentrated in the range of 2-7 *** on the seismic sequence profile and structural background,the M_(S)6.0 seismic structure may be a blind buried fault zone with a NW strike composed of multiple small conjugate faults with NE and SW *** fault was not exposed on the surface and was related to the detachment structure in the deep part of the Sichuan Basin.

关键词： Luxian M_(S)6.0 earthquake earthquake relocation seismogenic fault

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Optimization of cold-sprayed AA2024/Al_2O_3 metal matrix composites via friction stir processing: Effect of rotation speeds

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Journal of Materials Science & Technology 2018年第11期34卷 2167-2177页

作者： Kang Yang Wenya Li Chunjie Huang Xiawei Yang Yaxin Xu State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesSchool of Materials Science and EngineeringNorthwestern Polytechnical University IRTES EA7274 Université Bourgogne Franche-ComtéUTBMSite de Sévenans

In this study, friction stir processing（FSP） was employed to modify cold-sprayed（CSed） AA2024/Al2 O3 metal matrix composites（MMCs）. Three different rotation speeds with a constant traverse speed were used for FSP. Microstructural analysis of the FSPed specimens reveals significant Al2 O3 particle refinement and improved particle distribution over the as-sprayed deposits. After FSP, a microstructural and mechanical gradient MMC through the thickness direction was obtained. Therefore, a hybrid technique combining these two solid-state processes, i.e. CS and FSP, was proposed to produce functionally gradient deposits. The Guinier-Preston-Bagaryatskii zone was dissolved during FSP, while the amounts at different rotation speeds were approximately the same, which is possibly due to the excellent thermal conductivity of the used Cu substrate. Mechanical property tests confirm that FSP can effectively improve the tensile performance and Vickers hardness of CSed AA2024/Al2 O3 MMCs. The properties can be further enhanced with a larger rotation speed with a maximum increase of 25.9% in ultimate tensile strength and27.4% in elongation at 1500 rpm. Friction tests show that FSP decreases the wear resistance of CSed MMCs deposits due to the breakup of Al2 O3 particles. The average values and fluctuations of friction coefficients at different rotation speeds vary significantly.

关键词： Cold spray Friction stir processing Metal matrix composite Functionally gradient deposit Mechanical property Tribology

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Removal of Dye Using Lignin-Based Biochar/Poly(ester amide urethane)Nanocomposites from Contaminated Wastewater

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Journal of Renewable Materials 2024年第9期12卷 1507-1540页

作者： Annesha Kar Niranjan Karak Advanced Polymer and Nanomaterial Laboratory(APNL) Department of Chemical SciencesTezpur UniversityNapaamTezpur784028India Research and Development RymbalRTCSahibabad Industrial Area Site 4SahibabadGhaziabad201010India

The pursuit of incorporating eco-friendly reinforcing agents in polymer composites has accentuated the exploration of various natural biomass-derived *** burgeoning environmental crisis spurred by the discharge of synthetic dyes into wastewater has catalyzed the search for effective and sustainable treatment *** the various sorbent materials explored,biochar,being renewable,has gained prominence due to its excellent adsorption properties and environmental *** has also emerged as a focal point for its potential to replace other conventional reinforcing agents,viz.,fumed silica,aluminum oxide,treated clays,*** study introduces a novel class of polymer nanocomposites comprising of lignin-based biochar particles and poly(ester amide urethane)matrix via a feasible *** structural evaluation of these nanocomposites was accomplished using Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,and powder X-ray *** polymer nanocomposites exhibited superior mechanical properties with an increment in tensile strength factor by 45%in comparison to its pristine matrix,along with an excellent toughness value of 90.22 MJm^(−3)at a low loading amount of only 1 wt%.The composites showed excellent improvement in thermal properties with a sharp rise in the glass transition temperature(Tg)value from−28.15℃to 84℃,while also championing sustainability through inherent biodegradability *** their structural prowess,these polymer nanocomposites demonstrated excellent potential as adsorbents,displaying efficient removal of malachite green and tartrazine dyes from aqueous systems with a removal efficiency of 87.25%and 73.98%,*** kinetics study revealed the pseudo second order model to be the precision tool to assess the dye removal *** this,the Langmuir adsorption isotherm provided a framework to assess the sorption features of the polymer ***,these ren

关键词： Reinforcing agents biochar polymer nanocomposites poly(ester amide urethane) dye removal adsorption kinetics pseudo second order model langmuir isotherm

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INVERSE PROBLEM STABILITY OF A CONTINUOUS-IN-TIME FINANCIAL MODEL

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Acta Mathematica Scientia 2019年第5期39卷 1423-1439页

作者： Tarik CHAKKOUR Piaf INRA Site de Crou?l 5Chemin de Beaulieu

In this work, we study the inverse problem stability of the continuous-in-time model which is designed to be used for the finances of public institutions. We discuss this study with determining the Loan measure from algebraic spending measure in Radon measure space M([tI,Θmax]), and in Hilbert space L2([tI,Θmax]) when they are density measures. For this inverse problem we prove the uniqueness theorem, obtain a procedure for constructing the solution and provide necessary and sufficient conditions for the solvability of the inverse problem in L2([tI,Θmax]).

关键词： inverse problem stability mathematical model Fredholm operator

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一场对斯芬克斯之谜的思考

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艺术当代 2017年第2期16卷 74-75页

作者：肖浪无不详 para site

创意运营方案2016.12.10—2017.2.26香港Para site海运、贸易、鸦片,这三个词语几乎贯穿整个20世纪世界近代史,成为人类的伤口与勋章下的根基。远洋贸易带来不同场域文化之间的交流与冲击,在这个势头之下,世界—或是这个地球——在人们... 详细信息

创意运营方案2016.12.10—2017.2.26香港Para site海运、贸易、鸦片,这三个词语几乎贯穿整个20世纪世界近代史,成为人类的伤口与勋章下的根基。远洋贸易带来不同场域文化之间的交流与冲击,在这个势头之下,世界—或是这个地球——在人们的认知中变得越来越小。20世纪80年代,

关键词：斯芬克斯 20世纪80年代世界近代史远洋贸易运营方案

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Incorporation of nano/micron-SiC particles in Ni-based composite coatings towards enhanced mechanical and anti-corrosion properties

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International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 153-160页

作者： Bowei Zhang Qiao Zhang Zhan Zhang Kui Xiao Qiong Yao Guojia Ma Gang Sun Junsheng Wu Institute for advanced materials and technology University of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Key Laboratory of Space Lauching site Reliability Technology Haikou 571000China Department of Materials Application Research China Aviation Manufacturing Technology InstituteBeijing 100024China

Ni-based composite coatings incorporated with nano/micron SiC particles were fabricated via electrochemical co-deposition in Watts bath,followed by the evaluation of their mechanical and anti-corrosion *** micrographic observations suggest that the SiC particles with various sizes can be well incorporated to the Ni substrate.X-ray diffraction(XRD)patterns indicate that SiC particles with smaller sizes could weaken the preferential growth of Ni along(200)*** addition,it is found that the incorporated SiC particles with medium micron sizes(8 and 1.5μm)could significantly enhance the micro-hardness of the Ni composite ***,electrochemical measurements demonstrate that micron-sized SiC particles would weaken the corrosion resistance of Ni composite coatings ascribed to the structure defects *** contrast,the combined incorporation of nanosized(50 nm)SiC particles with medium micron(1.5μm)ones is capable of promoting the compactness of the composite coatings,which is beneficial to the long-term corrosion resistance with negligible micro-hardness loss.

关键词： Watts bath Ni coating SiC particles corrosion resistance electrodeposition

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Aerial vehicle guidance based on passive machine learning technique

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International Journal of Intelligent Computing and Cybernetics 2016年第3期9卷 255-273页

作者： Chethan Upendra Chithapuram Aswani Kumar Cherukuri Yogananda V.Jeppu School of Information Technology and Engineering(site) VIT UniversityVelloreIndia

Purpose-The purpose of this paper is to develop a new guidance scheme for aerial vehicles based on artificial *** new guidance scheme must be able to intercept maneuvering targets with higher probability and precision compared to existing ***/methodology/approach-A simulation setup of the aerial vehicle guidance problem is developed.A model-based machine learning technique known as Q-learning is used to develop a new guidance *** simulation experiments are conducted to train the new guidance *** arrays are used to define the training experiments to achieve faster convergence.A wellknown guidance scheme known as proportional navigation guidance(PNG)is used as a base model for *** new guidance scheme is compared for performance against standard guidance schemes like PNG and augmented proportional navigation guidance schemes in presence of sensor noise and computational ***-A new guidance scheme for aerial vehicles is developed using Q-learning *** new guidance scheme has better miss distances and probability of intercept compared to standard guidance *** limitations/implications-The research uses simulation models to develop the new guidance *** new guidance scheme is also evaluated in the simulation *** new guidance scheme performs better than standard existing guidance *** implications-The new guidance scheme can be used in various aerial guidance applications to reach a dynamically moving target in three-dimensional ***/value-The research paper proposes a completely new guidance scheme based on Q-learning whose performance is better than standard guidance schemes.

关键词： Monte Carlo simulation Machine learning Artificial intelligence Optimal guidance scheme Orthogonal arrays Proportional navigation guidance

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An Orientation Update Message Filtering Algorithm in Collaborative Virtual Environments

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Journal of Computer Science & Technology 2004年第3期19卷 423-428,F003页

作者： Mao-JunZhang NicolasD.Georganas GeneralSoftwareLaboratory InstituteofSoftwareTheChineseAcademyofSciencesBeijing100080P.R.China DiscoverLab SITEUniversityofOttawaOttawaCanada

Orientation update message filtering is an important issue in collaborativevirtual environments (CVEs). Dead-reckoning (DR) is a known effective mechanism for update messagefiltering. Yet, previous dead-reckoning techniques mainly focus on the update message filtering forpositions. The existing orientation dead-reckoning algorithms are based on fixed threshold *** drawbacks of fixed thresholding for orientations (FTO) are discussed in this paper. We propose avariable thresholding for orientations (VTO) based on average recent angular velocity. The mainadvantage of the proposed VTO is the ability of balancing the number of state update messages andshift frequency of direction and speed of rotation.

关键词： dead-reckoning orientation update message filtering variable thresholdingfor orientations average recent angular velocity collaborative virtual environments

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