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Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad m.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SfP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SfP was compared to HmA in terms of engineering characteristics and *** to the results,SfP was more resistant to skid,rutting,fire,and moisture damage,while HmA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SfP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

The Effects of Zinc Sulfate on the in Vitro Digestibility of feeds in Cervids

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Open Journal of Animal Sciences 2024年第3期14卷 157-167页

作者： Reese J. Thibodeaux Philip m. Urso Stanley f. Kelley marcy m. Beverly Chris R. Stewart Ian C. Dunn Gentech Diagnostics Dallas Texas USA Department of Animal Science South Dakota State University Brookings South Dakota USA School of Agricultural Sciences Sam Houston State University Huntsville Texas USA 3-S Texas Outdoors/3-S Whitetails Bedias Texas USA

The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (CON). following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADf, NDf, IVTD, or Om between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.

关键词： Zinc IVDmD In Vitro Cervids

fire resistance evaluation through synthetic fire tests and generative adversarial networks

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frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： AybikeÖzyükselÇiftçioğlua m.Z.Naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

This paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,Light Gradient Boosting machine,Categorical Boosting Algorithm,Support Vector Regression,Random forest,Decision Tree,multiple Linear Regression,Polynomial Regression,Support Vector machine,Kernel Support Vector machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian m.mawby Bellamarie Ludwig Benjamin J.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane fluidization Apparent density Carney flow

Complexed amino acid minerals ***-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： marcos J.B.Santos maria C.m.m.Ludke Leandro m.Silva Carlos B.V.Rabello mércia R.Barros fabiano S.Costa Clariana S.Santos Jamille S.S.Wanderley Department of Animal Science Rural Federal University of PernambucoRecifePEBrazil Department of Veterinary Science Rural Federal University of PernambucoRecifePEBrazil

The present study was to evaluate the effect of trace minerals(Zn,mn,and Cu)from complexed amino acid minerals(ZmCAA)and bis-glycinate chelated minerals(ZmCGly)in laying hen diets on performance,internal and external egg quality,yolk mineral deposition,intestinal morphometry,and bone *** 78 to 98 weeks of age,400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per *** were distributed in a 2×2 factorial arrangement using either Zn,mn,and Cu of ZmCAA or ZmCGly source at 2 levels:low(20,20,and 3.5 mg/kg of Zn,mn,and Cu,respectively)or high(40,40,and 7 mg/kg of Zn,mn,and Cu,respectively).The analysis of variance was performed,and in cases where differences were observed,the means were compared using Tukey?s test(Pf trace mineral supplementation had a significant impact on the performance of laying *** fed ZmCAA had higher egg production(P=0.01),egg weight(P=0.02),egg mass(P=0.01),and lower feed conversion ratio(P=0.05)compared to those fed *** ZmCAA supplementation showed higher albumen height(P=0.01),albumen weight(P=0.01),and eggshell thickness(Pf Zn(Pmn(Pfor hens received *** weight(P=0.04)and bone densitometry(PmCAA *** the small intestine,ZmCAA resulted in longer villi(P=0.02)and shorter crypt depth(P=0.01)in the *** and ileum measurements were influenced by the level and source of trace minerals(Pfed ZmCAA exhibited superior performance,egg quality,deposition of trace minerals in the egg yolk,and bone density compared to hens fed *** this study,older laying hens supplemented with ZmCAA at lower levels demonstrated adequate levels of supplementation.

关键词： Bis-glycinates metal-amino acids Radiodensity Trace minerals

Effect of cold-working on corrosion induced damage in lug joints

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Defence Technology（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath m.N Chikmath L. murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

Lug joints are preferred joineries for transferring heavy loads to parent components in aerospace *** experience corrosion due to environmental conditions,improper surface finishes and rubbing displacement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is modelled as a through-pit at one of the identified critical locations through stress *** effect of this pit on fatigue crack initiation life is ***-hole is pre-stressed by cold-working and the benefits of inducing plastic wake on the intended performance of the lug joint during the damages due to corrosion are brought out and compared with non-cold-worked *** analysis is performed on this lug joint with *** results obtained highlight the benefits of cold-working and the methodology can be extended to damage growth and analyse the effect of surface treatments for better structural integrity of components of aerospace vehicles.

关键词： Lug joint Corrosion Crack initiation Cold-working Structural integrity

Kinematic analysis of flexible bipedal robotic systems

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.fAZEL A.m.SHAfEI S.R.NEKOO Department of mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

On calculating glacial isostatic adjustment

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Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： L.m.Cathles Cornell University

modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity profile. Here, we compare two methods for calculating the viscoelastic response to surface loading. In one, the elastic equation of motion is converted to a viscoelastic equation using the Correspondence Principle. In the other, elastic deformation is added to the viscous flow as isostatic adjustment proceeds. The two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA). The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic pre-stress. The methods agree if they use the same equations and boundary conditions. The origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Correspondence principle Elastic buoyancy Glacial isostatic adjustment Hydrostatic pre-stress Viscoelastic normal modes

Endoscopic ultrasound-guided portal pressure gradient identifies patients with previously undiagnosed clinically significant portal hypertension

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Portal Hypertension & Cirrhosis 2024年第2期3卷 67-74页

作者： Jerome C.Edelson Scott f.D.Edelson John G.Quiles Cyrus V.Edelson Eric m.montminy Christian L.Horn John P.magulick Don C.Rockey Department of Gastroenterology and Hepatology Brooke Army Medical CenterFort Sam HoustonTexasUSA Department of medicine Uniformed Services University of the Health SciencesBethesdaMarylandUSA Department of medicine Brooke Army Medical CenterFort Sam HoustonTexasUSA John H.Stroger Jr.Hospital of Cook County ChicagoIllinoisUSA Digestive Disease Research Center Medical University of South CarolinaCharlestonSouth CarolinaUSA

Aims:Portal hypertension(PH)is a complication of cirrhosis that leads to hepatic *** the portal pressure gradient(PPG)provides valuable information for disease assessment,staging,and *** this study,we aimed to report the utilization of endoscopic ultrasound(EUS)-guided PPG(EUS-PPG)measurements in a real-world ***:This retrospective analysis included patients at a tertiary care center who underwent EUS-PPG between february 2021 and may *** most common indication was to establish or exclude the diagnosis of cirrhosis,followed by an assessment of surgical risk in the setting of suspected *** demographic and clinical data were collected,and statistical analysis was performed using the Student's t ***:Eighteen patients underwent *** success was achieved in 17 of the 18 *** complications were *** mean scores of Child-Pugh,model for End-Stage Liver Disease-Sodium,and fibrosis-4 scores were 5.1±0.5,9.0±3.0,and 3.7±4.5,*** the 18 patients,two presented with esophageal varices and six with portal hypertensive *** mean PPG was 5.8±4.5 mmHg,and five patients exhibited clinically significant PH(CSPH).Of the 18 patients,15 underwent concurrent EUS-liver biopsy,which was 100%successful and provided diagnostic histology for all *** PPG data led to changes in the clinical management of 17 ***:EUS-PPG is safe and technically *** Child-Pugh score did not correlate well with the presence of CSPH;however,PPG measurements resulted in changes in the management of almost all *** studies correlating EUS-PPG with other assessments of liver diseases are required.

关键词： EUS portal hypertension portal pressure gradient