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Control Theory and Technology 2021年第1期19卷 127-141页

作者： Jeisson E.Otero-Leal John Cortes-Romero Efredy Delgado Aguilera felipe galarza-jimenez Alexander jimenez-Triana Departamento de Eléctricay Electrónica Facultad de IngeníeraUniversidad Nacional de ColombiaBogotáD.C..Colombia Department of Control Engineering Universidad Distrital Francisco Joséde CaldasBogotáColombia

An adaptation of the active disturbance rejection control(AD RC)approach is applied to a fractional-order system with a flat *** the rather scarce information about the system,the conditions to establish an ultimate bound for a specific configuration of the system are found and compiled in a guideline for the tuning of the observer implemented in the ADRC.

关键词： ADRC Fractional-order system Ultimate bound Final value theorem

A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta Parra felipe Correa Mahecha Andrés felipe Rubio Pinzon Davidcamilo Ramirez Bustos Leonel Alveyro Teran Llorente Miguel Fernando jimenez jimenez Chemical and Environmental Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Chemical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering Department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach *** studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o *** study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating *** were performed using graphite electrodes with areas of 68.4 cm^(2) at the laboratory scale and 1865.0 cm^(2) at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was *** optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl_(2) per *** the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl_(2) per *** addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical *** 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency Optimization Sodium hypochlorite

Preventing brain aging by the artificial enforcement of the unfolded protein response:future directions

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Neural Regeneration Research 2024年第2期19卷 393-394页

作者： felipe Cabral-Miranda Claudio Hetz Instituto de Ciências Biomédicas Universidade Federal do Rio de JaneiroRio de JaneiroBrazil Center for Geroscience Brain Health and MetabolismSantiagoChile、Biomedical Neuroscience InstituteFaculty of MedicineUniversity of ChileSantiagoChile、Program of Cellular and Molecular BiologyInstitute of Biomedical SciencesFaculty of MedicineUniversity of ChileSantiagoChile、Buck Institute for Research on AgingNovatoCAUSA

As the life expectancy of the world’s population increases,age-related diseases are emerging as one of the greatest problems facing modern *** onset of dementia and neurodegenerative diseases is strictly dependent on aging as a major risk factor and has a profound impact on various aspects of the lives of individuals and their families.

关键词： diseases aging directions

The effect of ethanol fuel dilution on oil performance and MoDTC tribofilms formation and composition

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Friction 2024年第9期12卷 2108-2125页

作者： Juan RUIZ-ACERO felipe KESSLER Henara COSTA Tiago COUSSEAU Polytechnic School Universidade de São PauloSão Paulo 05508-030Brazil School of Food and Chemistry Universidade Federal do Rio GrandeRio Grande 96203-000Brazil School of Engineering Universidade Federal do Rio GrandeRio Grande 96203-900Brazil Mechanical Engineering Department Univ.Tecnológica Federal do ParanáCuritiba 81280-340Brazil University of Newcastle CallaghanSW 2308Australia

Ethanol has emerged as a promising alternative to fossil fuels,but its use can lead to significant dilution in lubricants,particularly during cold start or heavy *** dilution can affect the performance of additives,including friction modifiers like molybdenum dithiocarbamate(MoDTC),which are designed to reduce friction under extreme contact *** research suggests that ethanol may impact the performance of MoDTC,prompting this study’s goal to investigate the effects of ethanol on MoDTC tribofilms and their friction response under boundary lubrication ***,reciprocating tribological tests were performed with fully formulated lubricants containing MoDTC with varying ethanol *** results indicate that a critical ethanol dilution level inhibits friction reduction by MoDTC activation,resulting in friction coefficients(COFs)similar to the base *** tested with simple mixtures of polyalphaolefin(PAO)+MoDTC showed increased COFs with added *** of tested surfaces using Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and X-ray absorption spectroscopy near the edge structure(XANES)revealed the presence of sulfates,MoO_(3),MoS_(2),and MoS_(x)O_(y)compounds in the tribofilms formed on the surfaces,with and without ethanol diluted in the ***,the addition of ethanol increased the sulfates and MoO_(3)content of the tribofilms at the expense of friction-reducing compounds such as MoS_(2)and MoS_(x)O_(y).These findings suggest that ethanol dilution in lubricants containing MoDTC creates an oxygen-rich interfacial medium that favors the formation of compounds with insufficient friction-reducing capabilities.

关键词： molybdenum dithiocarbamate(MoDTC) ethanol tribofilm friction modifier additive lubricant

Three-dimensional seismic face stability of shield tunnels inundrained clay

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Underground Space 2024年第2期15卷 26-43页

作者： Milad Davoodi Salvador Senent Amin Keshavarz Rafael jimenez Civil Engineering Department School of EngineeringPersian Gulf UniversityBushehr ***Iran Universidad Polite´cnica de Madrid C/Prof.Aranguren s/nMadrid 28040Spain

Tunnel face stability has received increasing research interest over the past few decades. However, computing time-efficient and safethree-dimensional solutions under seismic loading is still an unsolved problem, while case studies indicate that seismic loading can be onecritical destabilizing factor affecting tunnel stability. The primary objective of this work is to fill this gap in knowledge by providing compromisingand computationally efficient solutions, along with their respective lower and upper bounds, to compute face stability underseismic conditions. The analyses employ the finite element limit analysis method to evaluate the limit support pressure in undrained clay,considering horizontal pseudo-static seismic forces pointing outwards from the face. Moreover, the analyses employ both constant andlinearly increasing shear strengths with depth. The results are summarized as dimensionless stability charts and tables to facilitate theirinterpretation and future use for tunnel design. A new design equation has been developed to evaluate the stability of the tunnel faceconsidering the effect of seismic forces. Additionally, the effects of different parameters on the shape of the failure mechanism have beeninvestigated by analysing the distribution of shear dissipation.

关键词： Tunnel face stability Finite element limit analysis Undrained clay Seismic stability

A review of torsional vibration mitigation techniques using active control and machine learning strategies

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Petroleum 2024年第3期10卷 411-426页

作者： Aditya Sharma Khizar Abid Saket Srivastava Andres felipe Baena Velasquez Catalin Teodoriu The University of Oklahoma NormanOKUSA

Drilling is one of the most challenging and expensive processes in hydrocarbon extraction and geothermal well *** faced during drilling can increase the non-productive time(NPT)greatly,resulting in inflating the drilling cost and also pose a safety *** of the main problems faced during drilling that limits the life of drilling equipment and tools and decreases the overall productivity of the system is drilling *** vibrations can be categorized into three modes:axial,lateral,and ***-slip vibrations are a type of torsional vibration in which the bottom hole assembly(BHA)periodically stops to rotate followed by a spike in the bottom hole *** paper provides a comprehensive review of techniques used to control and mitigate torsional vibration with an emphasis on stick-slip.A brief introduction to drillstring and friction modeling is presented followed by a concise summary of passive control techniques to control *** the focus is shifted to an up-to-date review of active control and machine learning for stick-slip control and *** paper ultimately highlights the importance of adapting novel control and mitigation concepts to improve stick slip detection and improve the overall drilling process.A unique solution is insufficient to control a complex process such as drilling,but integration of various techniques has been found promising.

关键词： Drilling vibrations Controllers Mitigations strategies Stick slip Torsional vibrations Machine Learning

Small-scale self-driving cars:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： felipe Caleffi Lauren da Silva Rodrigues Joice da Silva Stamboroski Brenda Medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil Mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language journals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACM Digital Library,and TRID databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a major benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto felipe Bravo iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

Geochemical elements in suspended particulate matter of Ensenada de La Paz Lagoon,Baja California Peninsula,Mexico:Sources,distribution,mass balance and ecotoxicological risks

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Journal of Environmental Sciences 2024年第2期136卷 422-436页

作者： Sandra Soledad Morales-García Pilar de Acacia Pérez-Escamilla Suresh Babu Sujitha Pichaimani Godwyn-Paulson Andrés felipe Zuniga-Cabezas Muthuswamy Ponniah Jonathan Instituto Politécnico Nacional(IPN) Centro Mexicano para la Producción más Limpia(CMPL)Av.Acueducto s/nCol.Barrio la Laguna TicománDel Gustavo A.MaderoC.P.07340Ciudad de MéxicoMexico Instituto Politécnico Nacional(IPN) Escuela Superior de Ingeniería y Arquitectura(ESIA)Unidad Ticomán***án 600Delg.Gustavo A.MaderoC.P.07340Ciudad de México(CDMX)Mexico Instituto Politécnico Nacional(IPN) Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo(CIIEMAD)Calle 30 de Junio de 1520Barrio la Laguna TicománDel.Gustavo A.MaderoC.P.07340Ciudad de MéxicoMéxico

The present study aimed to evaluate multi-element concentrations(Al,As,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,Pb,Sr)in suspended particulate material(SPM)collected from Ensenada de La Paz(ELP)lagoon,Baja California Sur,Mexico in two different periods(September and May)to comprehend their origin,geochemical behavior,mass transfer and associated ecotoxicological *** 24 hr variation coefficient of volumetric SPM levels were found to be 51.7%in September and 40.5%in May,signifying the effects of oceanic *** calculated enrichment factor(EF)values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM,and in this study,Mo had the highest EF of 46.77 probably due to its origin from continental *** the ecotoxicological perspective,the integrated toxic risk index revealed low toxic risk to the benthic ***,the mean-ERM-Quotient calculated using the particulate concentrations of As,Cd,Cr,Cu,Ni,Pb indicated 9%probability of toxicity to *** comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELP lagoon signify low to moderate contamination.

关键词： Suspended particulate material Heavy metals Risk assessment Mass transfer Ensenada de La Paz

CFD simulation of pumping ventilation in a three-story isolated building with internal partitioning:Effects of partition widths,heights and locations

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Building Simulation 2024年第2期17卷 267-284页

作者： Huai-Yu Zhong Jie Sun Chao Lin Song-Heng Wu Jin Shang Hideki Kikumoto Fu-Ping Qian Carlos jimenez-Bescos Fu-Yun Zhao School of Energy and Environment Anhui University of TechnologyMa-An-ShanAnhui Province243002China State Key Laboratory of Green Building in Western China Xi’an University of Architecture&TechnologyXi’anShaanxi ProvinceChina School of Power and Mechanical Engineering Wuhan UniversityWuhanHubei Province430072China Institute of Industrial Science The University of Tokyo4-6-1 KomabaMeguro-kuTokyo153-8505Japan School of Built and Natural Environment University of DerbyDerbyUK

Pumping ventilation(PV),a special single-sided ventilation(SSV),has been certified as an effective strategy to improve the air exchange rate of ***,most studies targeted on the single space,and few studies have been focused on the effect of internal partitioning on *** paper aims to evaluate the ventilation performance of PV influenced by different configurations of internal *** fluid dynamics(CFD)simulation was used to predict the flow fields and ventilation *** width(w/H),height(h/H)and location(d/H)are the three main internal partition parameters considered in this *** simulation results showed that the total,mean and fluctuating ventilation rates all decrease with wider internal *** normalized total ventilation rate decreases by 7.6%when w/H is increased from 50%to 75%.However,the reduction rate is only 0.23%between w/H=0 and 25%,and only 0.61%between w/H=25%and 50%.The ventilation rate is hardly reduced by increasing the partition width when w/H50%.Increasing the partition height will reduce the mean ventilation rate but promote the fluctuating and total ventilation rate in some *** increase of total ventilation rate by 1.4%is observed from h/H=50%to 75%.The ventilation rate is larger when the internal partition is attached to the leeward or windward *** total,mean and fluctuating ventilation rates for d/H=50%are relatively higher than d/H=0 by 1.5%,3.1%and 0.8%,*** the internal partition should be mounted attached to the windward wall so as to obtain the greatest pumping ventilation *** periodicity of pumping flow oscillation and pumping frequency are independent of the partition *** peak power of pumping flow is the lowest for the widest internal partition and is negatively affected by the partition height,but it generally has a positive correlation with the distance between the partition and leeward wa

关键词： pumping ventilation single-sided ventilation internal partitioning periodic oscillation ventilation rate