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Energy and AI 2024年第1期15卷 236-247页

作者： andre Adam Huazhen Fang Xianglin Li Department of mechanical Engineering University of Kansas1530 W 15th St.Lawrence66045KSUSA Department of mechanical Engineering and Materials Science Washington University in St.LouisOne Brookings DriveSt.Louis63130MOUSA

Topology optimization of heterogeneous structures can find significant use in a wide range of applications,and its fabrication has been made possible by recent advances in additive ***,the optimization procedure is computationally expensive,as each structural update requires the re-evaluation of the *** computational time is the major limiting factor in large-scale and complex structural *** this study,a convolutional neural network(CNN)model for predicting effective thermal conductivity inspired by the VGG networks is *** using 130,000 unique binary images,the model achieves high predictive ***,it shows a mean absolute percent error(MAPE)of 0.35%in testing when the thermal conductivity of the solid is ten times larger than the fluid,and when the thermal conductivities assigned are that of aluminum and water,the MAPE is 2.35%.The prediction time is 15 ms for a single image with 128×128 pixels,which is 3 to 5 orders of magnitude faster than a finite volume *** employed in topology optimization,the CNN retains a MAPE between 0.67%and 11.8%for different *** CNN model correctly predicts trends in effective thermal conductivity and improves the structure to close proximity of a theoretical maximum in all cases.

关键词： Machine learning Effective thermal conductivity Convolutional neural network VGG Numerical heat transfer Topology optimization

A New Family of Moths from the Middle Jurassic(Insecta:Lepidoptera)

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 874-885页

作者： HUANG Diying andre NEL Joeel MINET Nanjing Institute of Geology and Palaeontology State Key Laboratory of Palaeobiology and Stratigraphy Chinese Academy of Sciences Nanjing 210008 China UMR CNRS 7205 Museum National d＇Histoire Naturelle Departement Systematique et Evolution C.P. 50 Entomologie F-75231 Paris Cedex 05 France

Three lepidopteran species, from the Middle Jurassic Daohugou beds （inner Mongolia, China）, are described in a new family, mesokristenseniidae, and new genus, mesokristensenia, which could represent the sister group of the Micropterigidae. mesokristensenia differs from all extant Lepidoptera, but one genus （Agathiphaga, Agathiphagidae）, in retaining four median veins in the forewing, a plesiomorphy also present in many Trichoptera. Evidence for placing mesokristensenia in the Lepidoptera includes four traits, notably a previously unrecorded autapomorphy of this insect order： beyond stem Ml＋2, vein M1 is bent and connected to cross-vein r-m （in both wing pairs）. Among 24 characters taken into account to assess the systematic position of mesokristensenia, 12 are considered informative for a cladistic analysis involving this fossil taxon and the four suborders recognized in present-day Lepidoptera （Zeugloptera, Aglossata, Heterobathmiina, and Glossata）.

关键词： Trichoptera Lepidoptera mesokristenseniidae wing venation phylogeny China Middle Jurassic

Levothyroxine therapy and impaired clearance are the strongest contributors to small intestinal bacterial overgrowth: Results of a retrospective cohort study

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World Journal of Gastroenterology 2017年第5期23卷 842-852页

作者： Thorsten Brechmann andre Sperlbaum Wolff Schmiegel Department of Gastroenterology and Hepatology Berufsge--nossenschaftliches Universit?tsklinikum Bergmannsheil GmbHRuhr--University Bochum44789 BochumGermany

AIM To identify a set of contributors, and weight and rank them on a pathophysiological *** Patients who have undergone a lactulose or glucose hydrogen breath test to rule out small intestinal bacterial overgrowth(SIBO) for various clinical symptoms, including diarrhoea, weight loss, abdominal pain, cramping or bloating, were seen as eligible for inclusion in a retrospective single-centre study. Clinical data such as co-morbidities, medication, laboratory parameters and other possible risk factors have been identified from the electronic data system. Cases lacking or with substantially incomplete clinical data were excluded from the analysis. Suspected contributors were summarised under four different pathophysiological pathways(impaired gastric acid barrier, impaired intestinal clearance, immunosuppression and miscellaneous factors including thyroid gland variables) and investigated using the χ2 test, Student's t-test and logistic regression *** A total of 1809 patients who had undergone hydrogen breath testing were analysed. Impairment of the gastric acid barrier(gastrectomy, odds ratio: OR = 3.5, PPI therapy OR = 1.4), impairment of intestinal clearance(any resecting gastric surgery OR = 2.6, any colonicresection OR = 1.9, stenosis OR = 3.4, gastroparesis OR = 3.4, neuropathy 2.2), immunological factors(any drug-induced immunosuppression OR = 1.8), altered thyroid gland metabolism(hypothyroidism OR = 2.6, levothyroxine therapy OR = 3.0) and diabetes mellitus(OR = 1.9) were associated significantly to SIBO. Any abdominal surgery, ileocecal resection, vagotomy or Ig A-deficiency did not have any influence, and a history of appendectomy decreased the risk of SIBO. Multivariate analysis revealed gastric surgery, stenoses, medical immunosuppression and levothyroxine to be the strongest predictors. Levothyroxine therapy was the strongest contributor in a simplified model(OR = 3.0).CONCLUSION The most important contributors for the development of SI

关键词： Bacterial overgrowth syndrome Hydrogen breath tests Immunosuppression Intestinal motility Hypothyroidism

Fragility Assessment of Pre-Northridge Steel Moment Frames Using Finite-Length Plastic Hinge Elements and Concentrated Plasticity Fracture Elements

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 657-676页

作者： Filipe L.A.Ribeiro andre RBarbosa Luis CNeves National Laboratory of Civil Engineering(LNEC)&CERIS-Civil Engineering Research and Innovation for Sustainability DECivilUniversity of LisbonLisbonPortugal School of Civil and Construction Engineering Oregon State UniversityOregonUSA and University of BristolBristolUK Resilience Engineering Research Group University of NottinghamNottinghamUK.

Although pre-Northridge earthquake steel moment resisting frame buildings have been shown to be susceptible to brittle connection failures,they still represent a large fraction of the existing steel buildings in the United States of *** this study,the performance of the 3-and 9-story Los Angeles pre-Northridge SAC buildings are analyzed considering ductile and brittle beam-column connection failures,and their *** paper contributes to understanding the influence of uncertainty associated with connections brittle fracture on building interstory deformation capacity and its impact on bias and variability of fragility functions and loss *** results show that considering brittle connections leads to significantly l arger d rift demands a nd t o h igher r epair costs,particularly under intense ground *** fragility curve parameters are derived that account for the effect of the uncertainty of the strength and deformation capacity of brittle connections.

关键词： Brittle fracture finite-length p lastic h inge f ragility c urves r epair c ost ratio welded-flange connections

On the local convergence of a stochastic semismooth Newton method for nonsmooth nonconvex optimization

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Science China Mathematics 2022年第10期65卷 2151-2170页

作者： andre Milzarek Xiantao Xiao Zaiwen Wen Michael Ulbrich School of Data Science The Chinese University of Hong KongShenzhenShenzhen 518172China Shenzhen Research Institute of Big Data Shenzhen 518172China Shenzhen Institute of Arti cial Intelligence and Robotics for Society Shenzhen 518172China School of Mathematical Sciences Dalian University of TechnologyDalian 116024China Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China Department of Mathematics Technical University of MunichGarching bei Munchen 85748Germany

In this work,we present probabilistic local convergence results for a stochastic semismooth Newton method for a class of stochastic composite optimization problems involving the sum of smooth nonconvex and nonsmooth convex terms in the objective *** assume that the gradient and Hessian information of the smooth part of the objective function can only be approximated and accessed via calling stochastic firstand second-order *** approach combines stochastic semismooth Newton steps,stochastic proximal gradient steps and a globalization strategy based on growth *** present tail bounds and matrix concentration inequalities for the stochastic oracles that can be utilized to control the approximation errors via appropriately adjusting or increasing the sampling *** standard local assumptions,we prove that the proposed algorithm locally turns into a pure stochastic semismooth Newton method and converges r-linearly or r-superlinearly with high probability.

关键词： nonsmooth stochastic optimization stochastic approximation semismooth Newton method stochastic second-order information local convergence

Monitoring the effects of land transformation on African clawless otters(Aonyx capensis)using fecal glucocorticoid metabolite concentrations as a measure of stress

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Integrative Zoology 2020年第4期15卷 293-306页

作者： Tshepiso L.MAJELANTLE Trevor MCINTYRE andre GANSWINDT Mammal Research Institute Department of Zoology and EntomologyUniversity of PretoriaPretoriaSouth Africa Department of Life and Consumer Sciences University of South AfricaPretoriaSouth Africa Endocrine Research Laboratory Department of Anatomy and PhysiologyUniversity of PretoriaOnderstepoortSouth Africa Centre for Veterinary Wildlife Studies Faculty of Veterinary ScienceUniversity of PretoriaOnderstepoortSouth Africa

In a time of increasing environmental change caused by anthropogenic disturbance,there is a greater need to understand animal adaptations to manmade *** this regard,the measurement of stress-related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such *** aims of the present study were to validate fecal glucocorticoid metabolite(fGCM)concentrations as a measure of stress using samples from a male African clawless otter(Aonyx capensis;n=1)and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South *** the 5 different enzyme-immunoassays(EIA)tested,a cortisol and oxoetiocholanolone(measuring 11,17 dioxoandrostanes)EIA revealed the highest response(74%and 48%increase,respectively)30 and 24 hours after a stress event(translocation of a captive individual as part of its rehabilitation prior to release),respec*** both EIAs,fGCM concentrations were comparable for samples collected up to 3 h *** the cortisol EIA for subsequent analyses,fGCM concentrations of animals from the transformed area(n=20;mean[±SD]:0.468[±0.539]µg/g dry weight[DW])were significantly higher(P=0.013)than those from otters in the natural areas(n=17;0.242[±0.226]µg/g DW).These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.

关键词： African clawless otter fecal glucocorticoid metabolites non-invasive hormone measurement stress urbanization

CFD-DEM simulation and experimental investigation of the flow behavior of lunar regolith JSC-1A

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Particuology 2018年第5期16卷 34-43页

作者： Hendrik Otto kristin kerst Christoph Roloff Gabor Janiga andre katterfeld Chair of Conveying Technologies University of Magdeburg "Otto yon Guericke'MagdeburgGermany Laboratory of Fluid Dynamics and Technical Flows University of Magdeburg "Otto yon Guericke"MagdeburgGermany

Rovers on Mars and the Moon analyze the local geology by collecting samples of the upper layer in containers and *** the analysis,the complete discharge of samples from the reservoir must be *** of the low atmospheric pressure,reduced gravity,and different grain shapes of the bulk material,the discharge process is very different compared to that on *** this study,the behavior of lunar regolith JSC-1A in closed containers during discharge was investigated by analyzing the flow in an hourglass under the Earth's *** fluidization of the top particle layer was observed during the outflow of the upper half of the *** particles were fluidized by the displacement flow initiated by failing particles in the completely closed *** complex problem was simulated by coupling computational fluid dynamics (CFD)with the discrete element method (DEM). A CFD-DEM simulation with 1million particles was *** billions of particles are present in the actual system,the use of a coarse graining approach was *** addition,high-speed camera measurements were used to determine the velocities of individual particles to validate the simulation. The fluidization effect was successfully simulated using the coupled method.

关键词： CFD-DEM simulation Flow behavior Lunar regolith JSC-1A Experiment

Effect of gamification applications on success of dentistry students

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World Journal of methodology 2025年第1期15卷 80-87页

作者： Hatice Ahsen Deniz Elif Polat Balkan Burak İncebeyaz kıvanç kamburoğlu Department of Dentomaxillofacial Radiology Ankara University Faculty of DentistryAnkara 06500Türkiye

BACkGROUND Gamification,the use of game materials in education,has been used in several scientific fields,and studies have demonstrated its effectiveness in student *** To evaluate whether the success of 4th-and 5th-grade dentistry students increases when using the gamification applications kahoot!and *** An experimental design was used to measure the effect of gamification applications on students who were taught using the traditional *** this purpose,mentimeter and kahoot!applications were used in this experimental *** groups of 4th-and 5th-grade students were formed:mentimeter,kahoot!,and control *** effect of gamification applications on achievement was evaluated by administering a post-test to these groups after the instructional ***-way analysis of variance and t-tests were used for statistical *** A total of 35.5%of the students were in the mentimeter group,29.8%in the kahoot!group,and 34.6%in the control *** the total number of students,54.8%were female and 45.2%were male,while 52.2%were 5th-grade students and 47.8%were 4th-grade *** overall grade point average was found to be 66.65(range,24-100).There was a statistically significant difference in average success scores between students of different groups(P=0.003mentimeter group(71.64)and the lowest in the kahoot!group(62.15).In the control group,this score was *** average success score was higher for students in the 5thgrade(68.16)and for female students(68.84).CONCLUSION Gamification has a great potential in the education of dentomaxillofacial radiology *** outperformed both the kahoot!and the traditional method in terms of average student success rates.

关键词： Gamification mentimeter kahoot! Education Dentistry

A Composite Index-Based Approach for Mapping Ecosystem Service Production Hotspots and Coldspots for Priority Setting in Integrated Watershed Management Programs

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Journal of Geoscience and Environment Protection 2022年第4期10卷 49-63页

作者： Duncan kikoyo Srinivasulu ale Patricia Smith Texas A&M University College Station USA

Despite the potential synergism, integrated watershed management and ecosystem services frameworks are rarely used jointly to address the myriad of current water-related issues. The two frameworks are used in this study to spatially identify ecosystem hotspots and coldspots for priority setting in natural resource management programs. Inferred proxies of carbon storage, groundwater supply, surface water supply, and soil retention ecosystem service production potentials were quantified for Texas, U.S., using two complimentary hydro-ecological models, and valued using a non-monetary multi-criteria valuation approach. Maps of individual and composite ecosystem service values showed that several services were co-located and unevenly distributed with most of the high-value hotspots clustered in the eastern part of the state. Individual impacts of land use, climatic and soil properties on the distribution and value of ecosystem services across space were discernable. The study underscored the need for holistic management of landscapes to take advantage of the multiplicity of benefits provided by nature. The approach can readily be incorporated into resource management programs to identify high-value ecosystem service production areas that need conservation, low-value areas that may need restoration, and anthropogenic activities influencing the distribution of ecosystem services.

关键词： HAWQS InVEST Multi-Criteria Analysis Spatial Analysis Sustainability

Impact loads generated by tandem cavitation bubble on solid wall

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Journal of Hydrodynamics 2022年第3期34卷 467-482页

作者： Nyo me Thet Naing Jaehyun Park Seung-Ho Hyun Rho-Taek Jung School of Naval Architecture and Ocean Engineering University of UlsanUlsanKorea School of Electrical Engineering University of UlsanUlsanKorea Foundation for Industry Cooperation University of UlsanUlsanKorea

Experiments on two cavitation bubbles,which are generated at the same instant,with three different sizes near solid wall are conducted and their impulses on the boundary are registered by polyvinylidene fluoride(PVDF)*** to being near the boundary,bubble interactions and deformed features are in contrast with those in infinite fluid *** this paper,five morphologies of bubble deformation during growth and collapse phases are observed by high-speed *** profiles are strongly influenced by inter-bubble distance(η),stand-off distance from boundary(γ),and bubble size *** of photographs coupled with sensor measurements enabled qualitative investigation of two bubble interactions on the *** sensor data acquisition,it is confirmed that lower bigger bubble with upper smaller bubble configuration produces highest impulses on the boundary compared with other vertical arrangements of the tandem cavitation bubble employed in this study.

关键词： Two bubbles spark-generated bubble impulse polyvinylidene fluoride(PVDF)