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Response of saproxylic insect communities to logging history, tree species, stage of decay, and wood posture in the central Nearctic boreal forest

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Journal of Forestry Research 2018年第5期29卷 1365-1377页

作者： R.W.James Dennis Jay R.malcolm Sandy m.Smith m.Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks St.Toronto ON M5S 3B3 Canada Departamento de Ecología Genética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and IEGEBA (CONICET)Buenos Aires Argentina

Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest *** used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central *** clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was *** consistently emerged more from Populus than from Picea dead *** of the studied saproxylic families were more abundant in late-decay than in early-decay *** of the Cecidomyiidae,Ceratopogonidae,Empididae,mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead *** contrast,mymaridae was most abundant in standing dead *** study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.

关键词： Boreal forest Dead wood quality Forest harvesting High-level taxa Saproxylic insects

mobility of Arsenic and Heavy metals in a Sandy-Loam Textured and Carbonated Soil

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Pedosphere 2009年第2期19卷 166-175页

作者： I. GARC íA m. DIEZ F. mART íN m. SImóN C. DORRONSORO Departamento Edafologia y Quimica Agricola CITE IIB Carretera Sacramento s/n 04120 University of Almeria (Spain) Departamento Edafologia y Quimica Agricola Campus Fuentenueva s/n 18002 University of Granada (Spain)

The continued effect of the pyrite-tailing oxidation on the mobility of arsenic, lead, zinc, cadmium, and copper was studied in a carbonated soil under natural conditions, with the experimental plot preserved with a layer of tailing covering the soil during three years. The experimental area is located in Southern Spain and was affected by a pyrite-mine spill. The climate in the area is typically mediterranean, which determines the rate of soil alteration and element mobility. The intense alteration processes that occurred in the soil during three years caused important changes in its morphology and a strong degradation of the main soil properties. In this period, lead concentrated in the first 5 mm of the soil, with concentrations higher than 1500 mg kg?1, mainly associated to the neoformation of plumbojarosite. Arsenic was partially leached from the first 5 mm and mainly concentrated between 5–10 mm in the soil, with maximum values of 1239 mg kg-1; the retention of arsenates was related to the neoformation of iron hydroxysulfates (jarosite, schwertmannite) and oxyhydroxides (goethite, ferrihydrite), both with a variable degree of crystallinity. The mobility of Zn, Cd, and Cu was highly affected by pH, producing a stronger leaching in depth; their retention was related to the forms of precipitated aluminium and, in the case of Cu, also to the neoformation of hydroxysulfate.

关键词： arsenic heavy metals oxidation pyrite-tailing soil

Smooth quadrotor trajectory generation for tracking a moving target in cluttered environments

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Science China(Information Sciences) 2021年第7期64卷 132-147页

作者： Lele XI Zhihong PENG Lei JIAO Ben m.CHEN School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System Peng Cheng Laboratory Department of mechanical and Automation Engineering The Chinese University of Hong Kong

In this paper, we present a trajectory generation method of a quadrotor, based on the optimal smoothing B-spline, for tracking a moving target with consideration of relative tracking pattern or limited field of view of the onboard sensor in cluttered environments. Compared to existing methods, safe flying zone,vehicle physical limits, and smoothness are fully considered to guarantee flight safety, kinodynamic feasibility, and tracking performance. To tackle the cluttered environments, a parallel particle swarm optimization algorithm is applied to find the feasible waypoints that the generated trajectory should be as close to as possible, with consideration of the target’s future state as well as obstacles to trade off the tracking performance and flight safety. Then, a sequential motion planning method, considering the above constraints, is applied and embedded into a cost function for solving the problem of robust tracking trajectory generation for the quadrotor via a convex optimization approach. The feasibility and effectiveness of the proposed method are verified by numerical simulations.

关键词： quadrotor target tracking trajectory generation B-spline convex optimization

Flash Lamps as Ignition and Initiation Sources of the VS-2 Pyrotechnic Composition

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含能材料 2022年第4期30卷 370-378页

作者： Sergey I.Gerasimov mikhail A.Ilyushin Sergey m.Putis Sergey A.Dushenok Irina V.Shugalei Andrey m.Sudarikov Russian Federal Nuclear Center‑All‑Russian Research Institute of Experimental Physics SarovRussia Sarov Institute of Physics and Technology is a Branch of the Scientific Research Nuclear University mEPhI SarovRussia Nizhny Novgorod State Technical University Named after R.E.Alekseev Nizhny NovgorodRussia RAS Institute for Studying Problems in mechanical Engineering ‑is a Branch of the RAS Applied Physics InstituteNizhny NovgorodRussia "Technologist"Special Design and Technological Bureau St.PetersburgRussia Saint‑Petersburg State Institute of Technology(Technical University) St.PetersburgRussia Russian State Hydro‑meteorological University St.PetersburgRussia

In the present work it is found that the pyrotechnic composition VS⁃2 can be initiated with flash lamps IFC⁃500 and ***⁃2 pyrotechnic composition contains 90%of mercury(Ⅱ)5⁃hydrazinotetrazolate perchlorate and 10%of optically trans⁃parent copolymer of 2⁃methyl⁃5⁃vinyltetrazole and methacrylic acid(PVmT).We have found that the flash lamps make it possi⁃ble to initiate combustion of VS⁃2 composition with its transition to detonation both in cylindrical charges placed in brass caps of 5 mm diameter and 2 mm high,and film charges with 10 mm×80 mm in size and surface weights of 60 mg·cm^(-2)and 90 mg·cm^(-2),showing ignition delay times 10μs and 3μs,*** also measured detonation velocities for VS⁃2 composition film charges,which were 4375-4505 m·s^(-1)(of the charge being surface mass 60 mg·cm^(-2))and 4221-4281 m·s^(-1)(of the charge be⁃ing surface mass 90 mg·cm^(-2))and their blasting action on the aluminum *** depths of the normal shock wave imprints at the charge⁃barrier interface were 0.6-0.7 mm(for surface mass of the film charges 60 mg·cm^(-2))and 1.2-1.3 mm(for surface mass of the film charges 90 mg·cm^(-2))

关键词： VS⁃2 pyrotechnic composition flash lamps ignition transition of combustion to detonation blasting action

New applications of the two variable (G ′/ G,1/ G)-expansion method for closed form traveling wave solutions of integro-differential equations

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Journal of Ocean Engineering and Science 2019年第2期4卷 132-143页

作者： m.mamun miah H.m.Shahadat Ali m.Ali Akbar Aly R.Seadawy Department of mathematics Khulna University of Engineering and TechnologyBangladesh Department of Applied mathematics Noakhali Science and Technology UniversityBangladesh Department of Applied mathematics University of RajshahiBangladesh mathematics Department Faculty of ScienceTaibah UniversityAl-Madinah Al-MunawarahSaudi Arabia Department of mathematics Faculty of ScienceBeni-Suef UniversityEgypt

most fundamental themes in mathematical physics and modern engineering are investigated by the closed form traveling wave solutions of nonlinear evolution *** our research,we ascertain abundant new closed form traveling wave solution of the nonlinear integro-differential equations via Ito equation,integro-differential Sawada-Kotera equation,first integro-differential KP hierarchy equation and second integro-differential KP hierarchy equation by two variable(G/G,1/G)-expansion method with the help of computer package like *** shape of solutions like,bell profile solution,anti-king profile solution,soliton profile solution,periodic profile solution *** obtain in this *** function solution,hyperbolic function solution and rational function solution are established by using our eminent method and comparing with our results to all of the well-known results which are given in the *** means of free parameters,plentiful solitary solutions are derived from the exact traveling wave *** method can be easier and more applicable to investigate such type of nonlinear evolution models.

关键词： The two variable(G/G,1/G)-expansion method Travelling wave solutions Integro-differential ito equation Integro-differential Sawada-Kotera equation First integro-differential KP hierarchy equation Second integro-differential KP hierarchy equation.

Hydromagnetic oscillatory Couette flow in rotating system with induced magnetic field

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Applied mathematics and mechanics(English Edition) 2014年第10期35卷 1331-1344页

作者： G.S.SETH S.m.HUSSAIN S.SARKAR Department of Applied mathematics Indian School of Mines Department of mathematics O.P.Jindal Institute of Technology

This paper presents a study of hydromagnetic Couette flow of an incompress- ible and electrically conducting fluid between two parallel rotating plates, one of which is oscillating in its own plane. A uniform transverse magnetic field is used, and the induced magnetic field is taken into account. The exact solution to the governing equations is obtained in a closed form. The solution to the problem in the case of vanishing and small finite magnetic Prandtl numbers is also derived from the general solution. The asymp- totic behavior of the solution for large values of the frequency parameter is analyzed to gain some physical insights into the flow pattern. Expressions for the shear stress at both the oscillatory and stationary plates due to primary and secondary flows and mass flow rate in the primary and secondary flow directions are also obtained. The results of the fluid velocity and the induced magnetic field are presented. The shear stresses on the plates due to the primary and secondary flows and the corresponding mass flow rates are presented in a tabular form.

关键词： magnetic interaction parameter Ekman number frequency parameter,hydromagnetic Stokes-Ekman boundary layer magnetic diffusion boundary layer

The size-dependent elastohydrodynamic lubrication contact of a coated half-plane with non-Newtonian fluid

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Applied mathematics and mechanics(English Edition) 2021年第7期42卷 915-930页

作者： Jie SU Hongxia SONG Liaoliang KE S.m.AIZIKOVICH School of mechanical Engineering Tianjin UniversityTianjin 300350China School of mathematical Science Inner Mongolia UniversityHohhot 010021China Laboratory of Functionally Graded and Composite materials Research and Education Center"Materials"Don State Technical UniversityRostov-on-Don 344000Russia

Based on the couple-stress theory,the elastohydrodynamic lubrication(EHL)contact is analyzed with a consideration of the size *** lubricant between the contact surface of a homogeneous coated half-plane and a rigid punch is supposed to be the non-Newtonian *** density and viscosity of the lubricant are dependent on fluid *** of film thickness,in-plane stress,and fluid pressure are calculated by solving the nonlinear fluid-solid coupled equations with an iterative *** effects of the punch radius,size parameter,coating thickness,slide/roll ratio,entraining velocity,resultant normal load,and stiffness ratio on lubricant film thickness,in-plane stress,and fluid pressure are *** results demonstrate that fluid pressure and film thickness are obviously dependent on the size parameter,stiffness ratio,and coating thickness.

关键词： elastohydrodynamic lubrication(EHL) non-Newtonian fluid size effect couple-stress theory coating

GDNF to the rescue:GDNF delivery effects on motor neurons and nerves,and muscle re-innervation after peripheral nerve injuries

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Neural Regeneration Research 2022年第4期17卷 748-753页

作者： Alberto F.Cintrón-Colón Gabriel Almeida-Alves Juliana m.VanGyseghem John m.Spitsbergen Biological Sciences Department Western Michigan UniversityKalamazooMIUSA

Peripheral nerve injuries commonly occur due to trauma,like a traffic *** nerves get severed,causing motor neuron death and potential muscle *** current golden standard to treat peripheral nerve lesions,especially lesions with large(≥3 cm)nerve gaps,is the use of a nerve autograft or reimplantation in cases where nerve root avulsions *** not tended early,degeneration of motor neurons and loss of axon regeneration can occur,leading to loss of *** surgical procedures exist,patients often do not fully recover,and quality of life *** nerves have limited regeneration,and it is usually mediated by Schwann cells and neurotrophic factors,like glial cell line-derived neurotrophic factor,as seen in Wallerian *** cell line-derived neurotrophic factor is a neurotrophic factor known to promote motor neuron survival and neurite *** cell line-derived neurotrophic factor is upregulated in different forms of nerve injuries like axotomy,sciatic nerve crush,and compression,thus creating great interest to explore this protein as a potential treatment for peripheral nerve *** glial cell line-derived neurotrophic factor has shown positive effects in regeneration and functional recovery when applied in experimental models of peripheral nerve *** this review,we discuss the mechanism of repair provided by Schwann cells and upregulation of glial cell line-derived neurotrophic factor,the latest findings on the effects of glial cell line-derived neurotrophic factor in different types of peripheral nerve injuries,delivery systems,and complementary treatments(electrical muscle stimulation and exercise).Understanding and overcoming the challenges of proper timing and glial cell line-derived neurotrophic factor delivery is paramount to creating novel treatments to tend to peripheral nerve injuries to improve patients'quality of life.

关键词： electrical muscle stimulation exercise glial cell line-derived neurotrophic factor glial cell line-derived neurotrophic factor delivery motor neuron nerve gap neurotrophic factor peripheral nerve injury Schwann cells skeletal muscle atrophy

Interpretable modeling of metallurgical responses for an industrial coal column flotation circuit by XGBoost and SHAP-A “conscious-lab” development

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International Journal of mining Science and Technology 2021年第6期31卷 1135-1144页

作者： S.Chehreh Chelgani H.Nasiri m.Alidokht minerals and metallurgical Engineering Dept.of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologySE-97187 LuleåSweden Department of Computer Engineering Amirkabir University of TechnologyTehranIran Tabas Parvardeh Coal Company(TPCCO) BirjandIran

Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation *** a novel approach,this study implemented a conscious-lab "CL" for filling this *** this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time *** explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the *** could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF *** could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).

关键词： SHAP XGBoost Explainable AI Coal flotation Separation efficiency