Lack of driver's knowledge about the abrupt changes in pavement's friction and poor performance of the vehicle's stability,traction,and ABS controllers on the low friction surfaces are the most important f...Lack of driver's knowledge about the abrupt changes in pavement's friction and poor performance of the vehicle's stability,traction,and ABS controllers on the low friction surfaces are the most important factors affecting car crashes.Due to its direct relation to vehicle stability,accurate estimation of tire-road friction is of interest to all vehicle and tire companies.Many studies have been conducted in this field and researchers have used different tools and have proposed different algorithms.This literature survey introduces different approaches,which have been widely used to estimate the friction or other related parameters,and covers the recent literature that contains these methodologies.The emphasize of this review paper is on the algorithms and studies,which are more popular and have been repeated several times.The focus has been divided into two main groups:experiment-based and model-based approaches.Each of these main groups has several sub-categories,which are explained in the next few sections.Several summary tables are provided in which the overall feature of each approach is reviewed that gives the reader the general picture of different algorithms,which are widely used in friction estimation studies.展开更多
Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to impr...Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to improve the reliability of network.In this paper,demand response(DR)programs and smart charging/discharging of plug-in electric vehicles(PEVs)are investigated for improving the reliability of radial distribution systems adopting particle swarm optimization(PSO)algorithm.Such analysis is accomplished due to the positive effects of both DR and PEVs for dealing with emerging challenges of the world such as fossil fuel reserves reduction,urban air pollution and greenhouse gas emissions.Additionally,the prioritization of DR and PEVs is presented for improving the reliability and analyzing the characteristics of distribution networks.The reliability analysis is performed in terms of loss of load expectation(LOLE)and expected energy not served(EENS)indexes,where the characteristics contain load profile,load peak,voltage profile and energy loss.Numerical simulations are accomplished to assess the effectiveness and practicality of the proposed scheme.展开更多
The pumping ability and placement performance of fresh cemented paste backfill(CPB) in underground mined cavities depend on its rheological properties. Hence, it is crucial to understand the rheology of fresh CPB slur...The pumping ability and placement performance of fresh cemented paste backfill(CPB) in underground mined cavities depend on its rheological properties. Hence, it is crucial to understand the rheology of fresh CPB slurry, which is related to CPB mixture design and the temperature underground. This paper presented an experimental study investigating the effects of binder type, content, water chemical properties and content, and temperature, on the rheological properties of CPB material prepared using the tailings of a copper mine in South Australia. Portland cement(PC), a newly released commercially manufactured cement called Minecem(MC) and fly ash(FA) were used as the binders added to the mine tailing materials. Various amounts of two different water types were added to the mixtures in the preparation of backfill material slurry. Six different temperatures ranging from 5 to 60 °C were to investigate the effect of temperature on CPB rheology. Overall, the increasing water content and decreasing temperature lead to lower yield stress. Based on the results obtained from the rheological properties of CPB slurry, it was found that at room temperature(25 °C), with regards to the unconfined compressive strength(UCS) performance, the replacement of 4% PC mixed CPB(28 days UCS 425 k Pa) to 3% MC mixed CPB(28 days UCS 519 k Pa), reduced the slurry yield stress from 210.7 to 178.5 Pa. The results also showed that the chemical composition of water affects the yield stress of CPB slurry and that MC mitigates the negative effect of mine-processed water(MW) and thus lead to improve the rheological properties of the slurry. However, the results suggested that the rheological properties of a mixture using MC is very sensitive to the water volume and temperature change. Therefore, using MC in backfill requires better quality control in slump mixing.展开更多
AIM To performed a systematic review and meta-analysis to determine any possible differences in terms of effectiveness, safety and tolerability between existing colon-cleansing products in patients with inflammatory b...AIM To performed a systematic review and meta-analysis to determine any possible differences in terms of effectiveness, safety and tolerability between existing colon-cleansing products in patients with inflammatory bowel disease.METHODS Systematic searches were performed( January 1980-September 2016) using MEDLINE, EMBASE, Scopus, CENTRAL and ISI Web of knowledge for randomized trials assessing preparations with or without adjuvants, given in split and non-split dosing, and in high(> 3 L) or low-volume(2 L or less) regimens. Bowel cleansing quality was the primary outcome. Secondary outcomes included patient willingness-torepeat the procedure and side effects/complications.RESULTS Out of 439 citations, 4 trials fulfilled our inclusion criteria(n = 449 patients). One trial assessed the impact of adding simethicone to polyethylene glycol(PEG) 4 L with no effect on bowel cleansing quality, but a better tolerance. Another trial compared senna to castor oil, again without any differences in term of bowel cleansing. Two trials compared the efficacy of PEG high-volume vs PEG low-volume associated to an adjuvant in split-dose regimens: PEG low-dose efficacy was not different to PEG high-dose; OR = 0.84(0.37-1.92). A higher proportion of patients were willing to repeat low-volume preparations vs high-volume; OR = 5.11(1.31-20.0). CONCLUSION In inflammatory bowel disease population, PEG lowvolume regimen seems not inferior to PEG high-volume to clean the colon, and yields improved willingness-torepeat. Further additional research is urgently required to compare contemporary products in this population.展开更多
During the recent years,some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical materials.In this work,the Mg-2Zn-1Gd-1Ca(wt%)alloy as a new metallic bio-mate...During the recent years,some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical materials.In this work,the Mg-2Zn-1Gd-1Ca(wt%)alloy as a new metallic bio-material was produced by the casting process followed by the heat treatment.The samples of the alloy were solution treated at temperatures of 500,550,and 600°C and then quench aged at temperatures of 125,150,and 175°C.The results of SEM-EDS examinations indicated that the alloy microstructure consists ofα-Mg matrix and the Ca_(2)Mg_(6)Zn_(3)and Mg_(3)Gd_(2)Zn_(3)secondary phases.With regard to the results of Vickers hardness test,the temperatures of 500°C and 150°C were selected as the optimum solutionizing and aging temperatures,respectively.Moreover,the dissolution of casting precipitates and production of lattice distortion occurring after the solution treatment led to the reduction in ultimate shear strength up to 21%.But,the precipitation hardening and morphological changes taking place during the aging treatment improved the ultimate shear strength up to 32%.Furthermore,the results of electro-chemical and weight-loss measurements in a simulated body fluid indicated that the heat-treated alloy is a promising candidate for the Mg based alloys recently considered for the bio-medical applications.展开更多
The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in sp...The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in specimens with different aspect ratios was also examined.Peak stress,post-peak portion of stress-strain,brittleness,characteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect ratio.Strain patterns of the rocks were obtained by applying three-dimensional(3D) digital image correlation(DIC) technique.Unlike conventional strain measurement using strain gauges attached to specimen,3D DIC allowed not only measuring large strains,but more importantly,mapping the development of field strain throughout the compression test,i.e.in pre-and post-peak regimes.Field strain development in the surface of rock specimen suggests that strain starts localising progressively and develops at a lower rate in pre-peak regime.However,in post-peak regime,strains increase at different rates as local deformations take place at different extents in the vicinity and outside the localised zone.The extent of localised strains together with the rate of strain localisation is associated with the increase in rate of strength degradation.Strain localisation and local inelastic unloading outside the localised zone both feature post-peak regime.展开更多
The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. ...The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.展开更多
Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock structures.The ba...Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock structures.The basic data required may be obtained from visual observation and laboratory or field tests.However,owing to the discontinuous and variable nature of rock masses,it is difficult for rock engineers to directly obtain the specific design parameters needed.As an alternative,the use of geophysical methods in geomechanics such as seismography may largely address this problem.In this study,25 seismic profiles with the total length of 543 m have been scanned to determine the geomechanical properties of the rock mass in blocks Ⅰ,Ⅲ and Ⅳ-2 of the Choghart iron mine.Moreover,rock joint measurements and sampling for laboratory tests were conducted.The results show that the rock mass rating(RMR) and Q values have a close relation with P-wave velocity parameters,including P-wave velocity in field(V;).P-wave velocity in the laboratory(V;) and the ratio of V;V;(i.e.K;= V;/V;.However,Q value,totally,has greater correlation coefficient and less error than the RMR,In addition,rock mass parameters including rock quality designation(RQD),uniaxial compressive strength(UCS),joint roughness coefficient(JRC) and Schmidt number(RN) show close relationship with P-wave velocity.An equation based on these parameters was obtained to estimate the P-wave velocity in the rock mass with a correlation coefficient of 91%.The velocities in two orthogonal directions and the results of joint study show that the wave velocity anisotropy in rock mass may be used as an efficient tool to assess the strong and weak directions in rock mass.展开更多
Objective:To evaluate the possible association between Toll-interleukin 1 receptor(TIR) domain containing adaptor protein(TIRAP;also known as MAI.) rsl893352 and rs8l77374(S180L) gene polymorphisms and pulmonary tuber...Objective:To evaluate the possible association between Toll-interleukin 1 receptor(TIR) domain containing adaptor protein(TIRAP;also known as MAI.) rsl893352 and rs8l77374(S180L) gene polymorphisms and pulmonary tuberculosis(PTB) in a sample of Iranian population.Methods:This case-control study was performed on 174 PTB and 177 healthy subjects.Tetra amplification refractory mutation systetn-polymerase chain reaction(T-AKMS-PCR) was used to detect the polymorphisms.Results:Our finding showed that neither the overall Ckisqaare comparison of PTB and control subjects nor the logistic regression analysis indicated any association between rsl893352 polymorphism and PTB.Regarding rs8l77374 polymorphism,the CT genotype as well as CT+TT increased the risk of PTB in comparison with CC genotype(OR=4.73,95%CI=2.65-8.45,P<0.0001 and OR=6.47,95%C1=3.68-11.38,P<0.0001.respectively).The rs8177374 T allele increased the risk of PTB in comparison with C allele(OR=4.21.95%CI=2.43-7.26,P<0.0001).Conclusions:Our finding indicates that TIRAP rs8177374 polymorphism is associated with PTB in a sample of Iranian population.展开更多
Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types...Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types in which the grout material is injected to the pore spaces of the ground.In grouting operations,the grout quality is important to achieve the best results.There are four main characteristics for a grout mixture including bleeding,setting time,strength,and viscosity.In this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these characteristics.The ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural project.Effect of each abovementioned ingredient is profoundly investigated.Since each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is determined.The optimization is based on 200 grout mixture samples with different percentages of ingredients.Finally,some of these grout mixtures are chosen for the introduced project.It should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of soils.However,quality of a grout can be helpful to make an injection easier and reasonable.For example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents grouting.This paper tries to show some tests in easy way to achieve a desirable sample of grout.展开更多
The Industrialized Building System (IBS) was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures...The Industrialized Building System (IBS) was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures is an important factor that ensures stability of buildings subjected to dynamic loads from earthquakes, vehicles, and machineries. However, structural engineers still lack knowledge on the proper connection and detailed joints o fiBS structure construction. Therefore, this study proposes a special precast concrete wall-to-wall connection system for dynamic loads that resists multidirectional imposed loads and reduces vibration effects (PI2014701723). This system is designed to connect two adjacent precast wall panels by using two steel U-shaped channels (i.e., male and female joints). During casting, each joint is adapted for incorporation into a respective wall panel after considering the following conditions: one side of the steel channel opens into the thickness face of the panel; a U-shaped rubber is implemented between the two channels to dissipate the vibration effect; and bolts and nuts are used to create an extension between the two U-shaped male and female steel channels. The developed finite element model of the precast wall is subjected to cyclic loads to evaluate the performance of the proposed connection during an imposed dynamic load. Connection performance is then compared with conventional connections based on the energy dissipation, stress, deformation, and concrete damage in the plastic range. The proposed precast connection is capable of exceeding the energy absorption of precast walls subjected to dynamic load, thereby improving its resistance behavior in all principal directions.展开更多
Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ(BSCFNiO) perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO...Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ(BSCFNiO) perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO membrane reactor was studied for partial oxidation of methane over Ni/α-Al 2 O 3 catalyst.The time dependence of oxygen permeation rate and catalytic performance of BSCFNiO membrane during the catalyst initiation stage were investigated at 850 C.In unsteady state,oxygen permeation rate,methane conversion and CO selectivity were closely related to the state of the catalyst.After 300 min from the initial time,the reaction condition reached to steady state and oxygen permeation rate were obtained about 11.7cm 3 cm 2 min 1.Also,the performance of membrane reactor was studied at the temperatures between 750 and 950 C.The results demonstrated good performance for the membrane reactor,as CH 4 conversion and CO selectivity permeation rate reached 98% and 97.5%,respectively,and oxygen permeation rate was about 14.5 cm 3 cm 2 min 1 which was 6.8 times higher than that of air-helium gradient.Characterization of membrane surface by SEM after reaction showed that the original grains disappeared on both surfaces exposed to the air and reaction side,but XRD profile of the polished surface membrane indicated that the membrane bulk preserved the perovskite structure.展开更多
In situ tensile testing in a scanning electron microscope(SEM)in conjunction with high-resolution electron backscatter diffraction(HR-EBSD)under load was used to characterize the evolution of geometrically necessary d...In situ tensile testing in a scanning electron microscope(SEM)in conjunction with high-resolution electron backscatter diffraction(HR-EBSD)under load was used to characterize the evolution of geometrically necessary dislocation(GND)densities at individual grain boundaries as a function of applied strain in a polycrystalline Mg-4Al alloy.The increase in GND density was investigated at plastic strains of 0%,0.6%,2.2%,3.3% from the area including 76 grains and correlated with(i)geometric compatibility between slip systems across grain boundaries,and(ii)plastic incompatibility.We develop expressions for the grain boundary GND density evolution as a function of plastic strain and plastic incompatibility,from which uniaxial tensile stress-strain response of polycrystalline Mg-4Al are computed and compared with experimental measurement.The findings in this study contribute to understanding the mechanisms governing the strain hardening response of single-phase polycrystalline alloys and more reliable prediction of mechanical behaviors in diverse microstructures.展开更多
Despite modern medicine’s advancements,age-related neurological diseases like Alzheimer’s disease and Parkinson’s disease remain challenging due to high costs,side effects,and limited accessibility.Ayurveda,a tradi...Despite modern medicine’s advancements,age-related neurological diseases like Alzheimer’s disease and Parkinson’s disease remain challenging due to high costs,side effects,and limited accessibility.Ayurveda,a traditional Indian medicine system,offers Kadha tea as a potential herbal option.This review explores Kadha’s components(basil(Ocimum basilicum L.),black pepper(Piper nigrum L.),Cinnamon(Cinnamomum verum J.Presl),ginger(Zingiber officinale Roscoe),and raisin(Vitis vinifera L.))and their interaction with various neurological disorders.Studies suggest Kadha exhibits anti-inflammatory,antioxidant,and antiviral properties,potentially impacting Alzheimer’s disease,Parkinson’s disease,neurotoxicity,neuroinflammation,and brain trauma.By focusing on specific disease mechanisms and Kadha’s intergrade effects,this review aims to elucidate its potential role in managing age-related neurological disorders.展开更多
Thermal energy storage(TES) is of great importance in solving the mismatch between energy production and consumption.In this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat i...Thermal energy storage(TES) is of great importance in solving the mismatch between energy production and consumption.In this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat in latent thermal energy storage systems,plays a vital role as a means of TES efficiency.However,this field suffers from lack of a comprehensive investigation on the impact of various PCMs in terms of exergy.To address this issue,in this study,in addition to indicating the melting temperature and latent heat of various PCMs,the exergy destruction and exergy efficiency of each material are estimated and compared with each other.Moreover,in the present work the impact of PCMs mass and ambient temperature on the exergy efficiency is evaluated.The results proved that higher latent heat does not necessarily lead to higher exergy efficiency.Furthermore,to obtain a suitable exergy efficiency,the specific heat capacity and melting temperature of the PCMs must also be considered.According to the results,LiF-CaF_(2)(80.5%:19.5%,mass ratio) mixture led to better performance with satisfactory exergy efficiency(98.84%) and notably lower required mass compared to other PCMs.Additionally,the highest and lowest exergy destruction are belonged to GR25 and LiF-CaF_(2)(80.5:19.5) mixture,respectively.展开更多
The development of women’s higher education in China can be divided into four stages:emergence(1908-1948);foundation(1949-1976);accelerating development(1977-2008);and the qualitative leap(2009-2020).This work consid...The development of women’s higher education in China can be divided into four stages:emergence(1908-1948);foundation(1949-1976);accelerating development(1977-2008);and the qualitative leap(2009-2020).This work considers the principal institutional mechanisms that contributed to this development.First,flexibly planned parenthood gradually promoted gender equality and openness in society facilitated by systematic“awards,grants,and loans”initiatives to support women’s higher education economically.Second,compulsory education ensured that left-out and migrant children had access to higher education.Third,effective connectivity across different education types bridged education gaps between those with different levels of education.Fourth,China made great efforts to invite and integrate international experiences that promoted the development of women’s higher education.Looking beyond these achievements,we also discuss the future trends of women’s higher education in China.展开更多
The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal varieties.As a result,the work we performed involved selecting...The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal varieties.As a result,the work we performed involved selecting the database required for supervised deep learning,evaluating the performance of current techniques on unprocessed communication signals,and suggesting a deep learning networkbased method that would enable the classification of modulation types with the best possible ratio between computation time and accuracy.We started by examining the automatic classification models that are currently in usage.In light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensemble learning strategy based on adjusted Res Net and Transformer Neural Network,which is effective at extracting multi-scale features from the raw I/Q sequence data.Finally,we produced an architecture that is simple to use and apply to communication signals.The architecture of this solution is strong and optimal,enabling it to determine the type of modulation with up to 95%accuracy automatically.展开更多
目的:研究自体血清滴眼液对屈光性角膜切削术(PRK)后角膜上皮愈合的影响。方法:本研究共纳入20例40眼近视及近视散光患者,其中男性9例,女性11例。每例患者随机选取一眼作为研究组应用20%含自体血清的人工泪液,另一眼为对照组应用常规人...目的:研究自体血清滴眼液对屈光性角膜切削术(PRK)后角膜上皮愈合的影响。方法:本研究共纳入20例40眼近视及近视散光患者,其中男性9例,女性11例。每例患者随机选取一眼作为研究组应用20%含自体血清的人工泪液,另一眼为对照组应用常规人工泪液。PRK术中,40眼均于角膜表面居中放置直径8 mm的酒精储槽, 20%的酒精作用20s。术后每天观察直到角膜上皮愈合后,分别于1mo,6mo,12mo进行随访。上皮愈合时间为主要观察指标,并记录裸眼视力(UCVA),显然验光和混浊度。结果:两组间术前小瞳检影结果无明显差异。术后1d,2d,3d,研究组平均疼痛评分均显著低于对照组(P<0.05)。术后1d,3d,研究组的平均水平和垂直上皮缺损低于对照组(P<0.05)。研究组上皮完全愈合的平均时间比对照组短约0.7d(3.15±0.366d vs 3.85±0.587d,P=0.00)。结论:研究表明,应用自体血清滴眼液,通过加速角膜上皮愈合和减轻疼痛,从而缩短视力恢复时间,降低屈光性角膜切削术术后不适、混浊度和感染风险。展开更多
This paper proposes a novel concept of virus-like swimming robot in the range of nano to micro scales for biomedical applications. Viruses are submicroscopic, intracellular parasites that consist of nucleic acid genom...This paper proposes a novel concept of virus-like swimming robot in the range of nano to micro scales for biomedical applications. Viruses are submicroscopic, intracellular parasites that consist of nucleic acid genome and protein capsid. Their shapes help them to move within the infected host organisms and attach to host cells. In this paper, main geometrical features of the viral structure are utilized for conceptual design of the virus-inspired swimming robot and resultant thorny spherical shaped body is equipped with a new inclined and concentric multi-flagella propulsion system for operation in low Reynolds number fluid flow environment. In off-propulsion situation a theoretical formula is derived for thrust value estimation. On the other hand, to investigate the robot behavior in the fluid media in on-propulsion condition, flow field around the robot is simulated using a numerical strategy consisting of surface methods of regularized Stokeslet and Rotlet theory. For propulsion control of the robot a multilayer artificial neural network is designed and employed then flow field of the robot wake is analyzed using Lagrangian Coherent Structure (LCS) concept. Furthermore, potential characteristics and specific features of this kind of miniature robots are discussed as well as its application. The results indicate the capability of the miniature robot to perform complex missions in low Reynolds number fluid flow environment especially bodily fluid systems including lymphatic, urinary and cerebrospinal fluid (CSF) systems.展开更多
文摘Lack of driver's knowledge about the abrupt changes in pavement's friction and poor performance of the vehicle's stability,traction,and ABS controllers on the low friction surfaces are the most important factors affecting car crashes.Due to its direct relation to vehicle stability,accurate estimation of tire-road friction is of interest to all vehicle and tire companies.Many studies have been conducted in this field and researchers have used different tools and have proposed different algorithms.This literature survey introduces different approaches,which have been widely used to estimate the friction or other related parameters,and covers the recent literature that contains these methodologies.The emphasize of this review paper is on the algorithms and studies,which are more popular and have been repeated several times.The focus has been divided into two main groups:experiment-based and model-based approaches.Each of these main groups has several sub-categories,which are explained in the next few sections.Several summary tables are provided in which the overall feature of each approach is reviewed that gives the reader the general picture of different algorithms,which are widely used in friction estimation studies.
文摘Nowadays,utilities aim to find methods for improving the reliability of distribution systems and satisfying the customers by providing the continuity of power supply.Different methodologies exist for utilities to improve the reliability of network.In this paper,demand response(DR)programs and smart charging/discharging of plug-in electric vehicles(PEVs)are investigated for improving the reliability of radial distribution systems adopting particle swarm optimization(PSO)algorithm.Such analysis is accomplished due to the positive effects of both DR and PEVs for dealing with emerging challenges of the world such as fossil fuel reserves reduction,urban air pollution and greenhouse gas emissions.Additionally,the prioritization of DR and PEVs is presented for improving the reliability and analyzing the characteristics of distribution networks.The reliability analysis is performed in terms of loss of load expectation(LOLE)and expected energy not served(EENS)indexes,where the characteristics contain load profile,load peak,voltage profile and energy loss.Numerical simulations are accomplished to assess the effectiveness and practicality of the proposed scheme.
基金This research was partially funded by Mining Education Australia(MEA)and OZ Minerals,Australiatheir support is gratefully acknowledged.
文摘The pumping ability and placement performance of fresh cemented paste backfill(CPB) in underground mined cavities depend on its rheological properties. Hence, it is crucial to understand the rheology of fresh CPB slurry, which is related to CPB mixture design and the temperature underground. This paper presented an experimental study investigating the effects of binder type, content, water chemical properties and content, and temperature, on the rheological properties of CPB material prepared using the tailings of a copper mine in South Australia. Portland cement(PC), a newly released commercially manufactured cement called Minecem(MC) and fly ash(FA) were used as the binders added to the mine tailing materials. Various amounts of two different water types were added to the mixtures in the preparation of backfill material slurry. Six different temperatures ranging from 5 to 60 °C were to investigate the effect of temperature on CPB rheology. Overall, the increasing water content and decreasing temperature lead to lower yield stress. Based on the results obtained from the rheological properties of CPB slurry, it was found that at room temperature(25 °C), with regards to the unconfined compressive strength(UCS) performance, the replacement of 4% PC mixed CPB(28 days UCS 425 k Pa) to 3% MC mixed CPB(28 days UCS 519 k Pa), reduced the slurry yield stress from 210.7 to 178.5 Pa. The results also showed that the chemical composition of water affects the yield stress of CPB slurry and that MC mitigates the negative effect of mine-processed water(MW) and thus lead to improve the rheological properties of the slurry. However, the results suggested that the rheological properties of a mixture using MC is very sensitive to the water volume and temperature change. Therefore, using MC in backfill requires better quality control in slump mixing.
文摘AIM To performed a systematic review and meta-analysis to determine any possible differences in terms of effectiveness, safety and tolerability between existing colon-cleansing products in patients with inflammatory bowel disease.METHODS Systematic searches were performed( January 1980-September 2016) using MEDLINE, EMBASE, Scopus, CENTRAL and ISI Web of knowledge for randomized trials assessing preparations with or without adjuvants, given in split and non-split dosing, and in high(> 3 L) or low-volume(2 L or less) regimens. Bowel cleansing quality was the primary outcome. Secondary outcomes included patient willingness-torepeat the procedure and side effects/complications.RESULTS Out of 439 citations, 4 trials fulfilled our inclusion criteria(n = 449 patients). One trial assessed the impact of adding simethicone to polyethylene glycol(PEG) 4 L with no effect on bowel cleansing quality, but a better tolerance. Another trial compared senna to castor oil, again without any differences in term of bowel cleansing. Two trials compared the efficacy of PEG high-volume vs PEG low-volume associated to an adjuvant in split-dose regimens: PEG low-dose efficacy was not different to PEG high-dose; OR = 0.84(0.37-1.92). A higher proportion of patients were willing to repeat low-volume preparations vs high-volume; OR = 5.11(1.31-20.0). CONCLUSION In inflammatory bowel disease population, PEG lowvolume regimen seems not inferior to PEG high-volume to clean the colon, and yields improved willingness-torepeat. Further additional research is urgently required to compare contemporary products in this population.
基金The authors would like to thank Iran National Science Foundation and the research board of Sharif University of Technology,Tehran,Iran,for the financial support and the provision of research facilities used in this work.
文摘During the recent years,some Mg based alloys have extensively been considered as a new generation of degradable and absorbable bio-medical materials.In this work,the Mg-2Zn-1Gd-1Ca(wt%)alloy as a new metallic bio-material was produced by the casting process followed by the heat treatment.The samples of the alloy were solution treated at temperatures of 500,550,and 600°C and then quench aged at temperatures of 125,150,and 175°C.The results of SEM-EDS examinations indicated that the alloy microstructure consists ofα-Mg matrix and the Ca_(2)Mg_(6)Zn_(3)and Mg_(3)Gd_(2)Zn_(3)secondary phases.With regard to the results of Vickers hardness test,the temperatures of 500°C and 150°C were selected as the optimum solutionizing and aging temperatures,respectively.Moreover,the dissolution of casting precipitates and production of lattice distortion occurring after the solution treatment led to the reduction in ultimate shear strength up to 21%.But,the precipitation hardening and morphological changes taking place during the aging treatment improved the ultimate shear strength up to 32%.Furthermore,the results of electro-chemical and weight-loss measurements in a simulated body fluid indicated that the heat-treated alloy is a promising candidate for the Mg based alloys recently considered for the bio-medical applications.
基金supported by the Deep Exploration Technologies Cooperative Research Centre whose activities are funded by the Australian Government's Cooperative Research Centre Programme.This is DET CRC Document 2017/954
文摘The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in specimens with different aspect ratios was also examined.Peak stress,post-peak portion of stress-strain,brittleness,characteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect ratio.Strain patterns of the rocks were obtained by applying three-dimensional(3D) digital image correlation(DIC) technique.Unlike conventional strain measurement using strain gauges attached to specimen,3D DIC allowed not only measuring large strains,but more importantly,mapping the development of field strain throughout the compression test,i.e.in pre-and post-peak regimes.Field strain development in the surface of rock specimen suggests that strain starts localising progressively and develops at a lower rate in pre-peak regime.However,in post-peak regime,strains increase at different rates as local deformations take place at different extents in the vicinity and outside the localised zone.The extent of localised strains together with the rate of strain localisation is associated with the increase in rate of strength degradation.Strain localisation and local inelastic unloading outside the localised zone both feature post-peak regime.
文摘The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.
文摘Engineering rock mass classification,based on empirical relations between rock mass parameters and engineering applications,is commonly used in rock engineering and forms the basis for designing rock structures.The basic data required may be obtained from visual observation and laboratory or field tests.However,owing to the discontinuous and variable nature of rock masses,it is difficult for rock engineers to directly obtain the specific design parameters needed.As an alternative,the use of geophysical methods in geomechanics such as seismography may largely address this problem.In this study,25 seismic profiles with the total length of 543 m have been scanned to determine the geomechanical properties of the rock mass in blocks Ⅰ,Ⅲ and Ⅳ-2 of the Choghart iron mine.Moreover,rock joint measurements and sampling for laboratory tests were conducted.The results show that the rock mass rating(RMR) and Q values have a close relation with P-wave velocity parameters,including P-wave velocity in field(V;).P-wave velocity in the laboratory(V;) and the ratio of V;V;(i.e.K;= V;/V;.However,Q value,totally,has greater correlation coefficient and less error than the RMR,In addition,rock mass parameters including rock quality designation(RQD),uniaxial compressive strength(UCS),joint roughness coefficient(JRC) and Schmidt number(RN) show close relationship with P-wave velocity.An equation based on these parameters was obtained to estimate the P-wave velocity in the rock mass with a correlation coefficient of 91%.The velocities in two orthogonal directions and the results of joint study show that the wave velocity anisotropy in rock mass may be used as an efficient tool to assess the strong and weak directions in rock mass.
文摘Objective:To evaluate the possible association between Toll-interleukin 1 receptor(TIR) domain containing adaptor protein(TIRAP;also known as MAI.) rsl893352 and rs8l77374(S180L) gene polymorphisms and pulmonary tuberculosis(PTB) in a sample of Iranian population.Methods:This case-control study was performed on 174 PTB and 177 healthy subjects.Tetra amplification refractory mutation systetn-polymerase chain reaction(T-AKMS-PCR) was used to detect the polymorphisms.Results:Our finding showed that neither the overall Ckisqaare comparison of PTB and control subjects nor the logistic regression analysis indicated any association between rsl893352 polymorphism and PTB.Regarding rs8l77374 polymorphism,the CT genotype as well as CT+TT increased the risk of PTB in comparison with CC genotype(OR=4.73,95%CI=2.65-8.45,P<0.0001 and OR=6.47,95%C1=3.68-11.38,P<0.0001.respectively).The rs8177374 T allele increased the risk of PTB in comparison with C allele(OR=4.21.95%CI=2.43-7.26,P<0.0001).Conclusions:Our finding indicates that TIRAP rs8177374 polymorphism is associated with PTB in a sample of Iranian population.
文摘Grout injection is used for sealing or strengthening the ground in order to prevent water entrance or any failure after excavation.There are many methods of grouting.Permeation grouting is one of the most common types in which the grout material is injected to the pore spaces of the ground.In grouting operations,the grout quality is important to achieve the best results.There are four main characteristics for a grout mixture including bleeding,setting time,strength,and viscosity.In this paper,we try to build some efficient grouting mixtures with different water to cement ratios considering these characteristics.The ingredients of grout mixtures built in this study are cement,water,bentonite,and some chemical additives such as sodium silicate,sodium carbonate,and triethanolamine(TEA).The grout mixtures are prepared for both of the sealing and strengthening purposes for a structural project.Effect of each abovementioned ingredient is profoundly investigated.Since each ingredient may have positive or negative aspect,an optimization of appropriate amount of each ingredient is determined.The optimization is based on 200 grout mixture samples with different percentages of ingredients.Finally,some of these grout mixtures are chosen for the introduced project.It should be mentioned that grouting operations depend on various factors such as pressure of injection,ground structure and grain size of soils.However,quality of a grout can be helpful to make an injection easier and reasonable.For example,during the injection,a wrong estimated setting time can destroy the injected grout by washing the grout or setting early which prevents grouting.This paper tries to show some tests in easy way to achieve a desirable sample of grout.
基金financial support from the Housing Research Center of UPMNAEIM Company
文摘The Industrialized Building System (IBS) was recently introduced to minimize the time and cost of project construction. Accordingly, ensuring the integration of the connection of precast components in IBS structures is an important factor that ensures stability of buildings subjected to dynamic loads from earthquakes, vehicles, and machineries. However, structural engineers still lack knowledge on the proper connection and detailed joints o fiBS structure construction. Therefore, this study proposes a special precast concrete wall-to-wall connection system for dynamic loads that resists multidirectional imposed loads and reduces vibration effects (PI2014701723). This system is designed to connect two adjacent precast wall panels by using two steel U-shaped channels (i.e., male and female joints). During casting, each joint is adapted for incorporation into a respective wall panel after considering the following conditions: one side of the steel channel opens into the thickness face of the panel; a U-shaped rubber is implemented between the two channels to dissipate the vibration effect; and bolts and nuts are used to create an extension between the two U-shaped male and female steel channels. The developed finite element model of the precast wall is subjected to cyclic loads to evaluate the performance of the proposed connection during an imposed dynamic load. Connection performance is then compared with conventional connections based on the energy dissipation, stress, deformation, and concrete damage in the plastic range. The proposed precast connection is capable of exceeding the energy absorption of precast walls subjected to dynamic load, thereby improving its resistance behavior in all principal directions.
文摘Ba0.5Sr0.5Co0.8Fe0.1Ni0.1O3δ(BSCFNiO) perovskite oxides were synthesized using a combined EDTA-citrate complexation method,and then pressed into disk and applied in a membrane reactor.The performance of the BSCFNiO membrane reactor was studied for partial oxidation of methane over Ni/α-Al 2 O 3 catalyst.The time dependence of oxygen permeation rate and catalytic performance of BSCFNiO membrane during the catalyst initiation stage were investigated at 850 C.In unsteady state,oxygen permeation rate,methane conversion and CO selectivity were closely related to the state of the catalyst.After 300 min from the initial time,the reaction condition reached to steady state and oxygen permeation rate were obtained about 11.7cm 3 cm 2 min 1.Also,the performance of membrane reactor was studied at the temperatures between 750 and 950 C.The results demonstrated good performance for the membrane reactor,as CH 4 conversion and CO selectivity permeation rate reached 98% and 97.5%,respectively,and oxygen permeation rate was about 14.5 cm 3 cm 2 min 1 which was 6.8 times higher than that of air-helium gradient.Characterization of membrane surface by SEM after reaction showed that the original grains disappeared on both surfaces exposed to the air and reaction side,but XRD profile of the polished surface membrane indicated that the membrane bulk preserved the perovskite structure.
基金supported by the U.S.Department of Energy,Office of Basic Energy Sciences,Division of Materials Sciences and Engineering under Award#DE-SC0008637 as part of the Center for PRedictive Integrated Materials Science(PRISMS Center)at the University of Michigan。
文摘In situ tensile testing in a scanning electron microscope(SEM)in conjunction with high-resolution electron backscatter diffraction(HR-EBSD)under load was used to characterize the evolution of geometrically necessary dislocation(GND)densities at individual grain boundaries as a function of applied strain in a polycrystalline Mg-4Al alloy.The increase in GND density was investigated at plastic strains of 0%,0.6%,2.2%,3.3% from the area including 76 grains and correlated with(i)geometric compatibility between slip systems across grain boundaries,and(ii)plastic incompatibility.We develop expressions for the grain boundary GND density evolution as a function of plastic strain and plastic incompatibility,from which uniaxial tensile stress-strain response of polycrystalline Mg-4Al are computed and compared with experimental measurement.The findings in this study contribute to understanding the mechanisms governing the strain hardening response of single-phase polycrystalline alloys and more reliable prediction of mechanical behaviors in diverse microstructures.
文摘Despite modern medicine’s advancements,age-related neurological diseases like Alzheimer’s disease and Parkinson’s disease remain challenging due to high costs,side effects,and limited accessibility.Ayurveda,a traditional Indian medicine system,offers Kadha tea as a potential herbal option.This review explores Kadha’s components(basil(Ocimum basilicum L.),black pepper(Piper nigrum L.),Cinnamon(Cinnamomum verum J.Presl),ginger(Zingiber officinale Roscoe),and raisin(Vitis vinifera L.))and their interaction with various neurological disorders.Studies suggest Kadha exhibits anti-inflammatory,antioxidant,and antiviral properties,potentially impacting Alzheimer’s disease,Parkinson’s disease,neurotoxicity,neuroinflammation,and brain trauma.By focusing on specific disease mechanisms and Kadha’s intergrade effects,this review aims to elucidate its potential role in managing age-related neurological disorders.
文摘Thermal energy storage(TES) is of great importance in solving the mismatch between energy production and consumption.In this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat in latent thermal energy storage systems,plays a vital role as a means of TES efficiency.However,this field suffers from lack of a comprehensive investigation on the impact of various PCMs in terms of exergy.To address this issue,in this study,in addition to indicating the melting temperature and latent heat of various PCMs,the exergy destruction and exergy efficiency of each material are estimated and compared with each other.Moreover,in the present work the impact of PCMs mass and ambient temperature on the exergy efficiency is evaluated.The results proved that higher latent heat does not necessarily lead to higher exergy efficiency.Furthermore,to obtain a suitable exergy efficiency,the specific heat capacity and melting temperature of the PCMs must also be considered.According to the results,LiF-CaF_(2)(80.5%:19.5%,mass ratio) mixture led to better performance with satisfactory exergy efficiency(98.84%) and notably lower required mass compared to other PCMs.Additionally,the highest and lowest exergy destruction are belonged to GR25 and LiF-CaF_(2)(80.5:19.5) mixture,respectively.
基金“Promoting research by writing”:Exploring the code of writing,supported by the Special Fund for basic scientific research of the Central University,Northwestern Polytechnical University(project no.KCJS23WT25).“Research on the construction of the linking-up curriculum system:Taking the industry characteristic research university as an example”was established by the Ministry of Education’s Youth Fund for Humanities and Social Sciences,the Department of Social Sciences of the Ministry of Education(project no.23YJC880099).
文摘The development of women’s higher education in China can be divided into four stages:emergence(1908-1948);foundation(1949-1976);accelerating development(1977-2008);and the qualitative leap(2009-2020).This work considers the principal institutional mechanisms that contributed to this development.First,flexibly planned parenthood gradually promoted gender equality and openness in society facilitated by systematic“awards,grants,and loans”initiatives to support women’s higher education economically.Second,compulsory education ensured that left-out and migrant children had access to higher education.Third,effective connectivity across different education types bridged education gaps between those with different levels of education.Fourth,China made great efforts to invite and integrate international experiences that promoted the development of women’s higher education.Looking beyond these achievements,we also discuss the future trends of women’s higher education in China.
文摘The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal varieties.As a result,the work we performed involved selecting the database required for supervised deep learning,evaluating the performance of current techniques on unprocessed communication signals,and suggesting a deep learning networkbased method that would enable the classification of modulation types with the best possible ratio between computation time and accuracy.We started by examining the automatic classification models that are currently in usage.In light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensemble learning strategy based on adjusted Res Net and Transformer Neural Network,which is effective at extracting multi-scale features from the raw I/Q sequence data.Finally,we produced an architecture that is simple to use and apply to communication signals.The architecture of this solution is strong and optimal,enabling it to determine the type of modulation with up to 95%accuracy automatically.
文摘目的:研究自体血清滴眼液对屈光性角膜切削术(PRK)后角膜上皮愈合的影响。方法:本研究共纳入20例40眼近视及近视散光患者,其中男性9例,女性11例。每例患者随机选取一眼作为研究组应用20%含自体血清的人工泪液,另一眼为对照组应用常规人工泪液。PRK术中,40眼均于角膜表面居中放置直径8 mm的酒精储槽, 20%的酒精作用20s。术后每天观察直到角膜上皮愈合后,分别于1mo,6mo,12mo进行随访。上皮愈合时间为主要观察指标,并记录裸眼视力(UCVA),显然验光和混浊度。结果:两组间术前小瞳检影结果无明显差异。术后1d,2d,3d,研究组平均疼痛评分均显著低于对照组(P<0.05)。术后1d,3d,研究组的平均水平和垂直上皮缺损低于对照组(P<0.05)。研究组上皮完全愈合的平均时间比对照组短约0.7d(3.15±0.366d vs 3.85±0.587d,P=0.00)。结论:研究表明,应用自体血清滴眼液,通过加速角膜上皮愈合和减轻疼痛,从而缩短视力恢复时间,降低屈光性角膜切削术术后不适、混浊度和感染风险。
文摘This paper proposes a novel concept of virus-like swimming robot in the range of nano to micro scales for biomedical applications. Viruses are submicroscopic, intracellular parasites that consist of nucleic acid genome and protein capsid. Their shapes help them to move within the infected host organisms and attach to host cells. In this paper, main geometrical features of the viral structure are utilized for conceptual design of the virus-inspired swimming robot and resultant thorny spherical shaped body is equipped with a new inclined and concentric multi-flagella propulsion system for operation in low Reynolds number fluid flow environment. In off-propulsion situation a theoretical formula is derived for thrust value estimation. On the other hand, to investigate the robot behavior in the fluid media in on-propulsion condition, flow field around the robot is simulated using a numerical strategy consisting of surface methods of regularized Stokeslet and Rotlet theory. For propulsion control of the robot a multilayer artificial neural network is designed and employed then flow field of the robot wake is analyzed using Lagrangian Coherent Structure (LCS) concept. Furthermore, potential characteristics and specific features of this kind of miniature robots are discussed as well as its application. The results indicate the capability of the miniature robot to perform complex missions in low Reynolds number fluid flow environment especially bodily fluid systems including lymphatic, urinary and cerebrospinal fluid (CSF) systems.