In order to increase the accuracy of microscopic traffic flow simulation,two acceleration models are presented to simulate car-following behaviors of the lane-changing vehicle and following putative vehicle during the...In order to increase the accuracy of microscopic traffic flow simulation,two acceleration models are presented to simulate car-following behaviors of the lane-changing vehicle and following putative vehicle during the discretionary lanechanging preparation( DLCP) process, respectively. The proposed acceleration models can reflect vehicle interaction characteristics. Samples used for describing the starting point and the ending point of DLCP are extracted from a real NGSIM vehicle trajectory data set. The acceleration model for a lanechanging vehicle is supposed to be a linear acceleration model.The acceleration model for the following putative vehicle is constructed by referring to the optimal velocity model,in which optimal velocity is defined as a linear function of the velocity of putative leading vehicle. Similar calibration,a hypothesis test and parameter sensitivity analysis were conducted on the acceleration model of the lane-changing vehicle and following putative vehicle,respectively. The validation results of the two proposed models suggest that the training and testing errors are acceptable compared with similar works on calibrations for car following models. The parameter sensitivity analysis shows that the subtle observed error does not lead to severe variations of car-following behaviors of the lane-changing vehicle and following putative vehicle.展开更多
Incidence of defects in MoSi2 rods prepared by con- tinuous extrusion is dependent on the viscosity of binder. Generally, low viscosity results in surface defects while high viscosity is responsible for inner defects....Incidence of defects in MoSi2 rods prepared by con- tinuous extrusion is dependent on the viscosity of binder. Generally, low viscosity results in surface defects while high viscosity is responsible for inner defects. Cross-section observations indicated that the typical inner defects in sintered MoSi2 rods were large fissure cavity, multiple small holes and single small cavity, of which the characteristic ultrasonic reflection patterns have been experimentally established. Formation of the inner defects is attributed to the inhomogeneous feedstock moving behav- ior in die, which is aggravated with increasing viscosity of binder. Defect free MoSi2 rods were prepared successfully via con. tinuous extrusion by carefully controlling the viscosity of binder.展开更多
Background:Pediatric cardiology patients often experience decreased quality of life(QoL)and higher rates of mental illness,particularly with severe disease,but the relationship between them and comparisons across diag...Background:Pediatric cardiology patients often experience decreased quality of life(QoL)and higher rates of mental illness,particularly with severe disease,but the relationship between them and comparisons across diagnostic groups are limited.This mixed-methods cross-sectional study assessed the association between QoL anxiety and behavior problems among children with structural heart disease,arrhythmia,or other cardiac diagnoses.Methods:Children(6–14 years,n=76,50%female)and their parents completed measures of QoL(PedsQL),behavior(BASC-2,subset of 19 children)and anxiety(MASC-2,children 8+years).Pearson correlations/regression models examined associations between QoL,behavior and anxiety,controlling for age,sex,diagnosis and condition severity.Student t-tests compared results to published normative values.Semi-structured interviews(15 children,13 parents)examined self-and parent-reported perceptions of the patient’s emotional health.Results:Child reported social QoL(95%CI difference:−11.0,−2.1),emotional well-being(95%CI difference:−12.5,−3.8)and adjustment skills(95%CI difference:−13.9,−3.0)were significantly below published norms(p<0.05).Neither age,sex,nor diagnosis were significantly related to questionnaire responses.Compared to children with mild conditions,child and parent-reported QoL was significantly lower in children with complex conditions(np2≥0.14,p<0.05).Lower QoL was strongly associated with more internalizing problems based on both child(r=−0.78,p<0.001)and parent(r=−0.67,p<0.001)reports.Interview responses suggested emotional distress was attributed to“normal”child problems rather than the child’s cardiac problem.Conclusion:Children with complex cardiac conditions,regardless of diagnosis,had diminished QoL.Using the PedsQL in clinical settings may help identify pediatric cardiology patients experiencing emotional distress(i.e.,anxiety and depression).展开更多
Metallic nanolaminated materials possess excellent mechanical properties due to their unique modulation structures and interfacial properties.However,how microdefects affect their mechanical properties is still uncert...Metallic nanolaminated materials possess excellent mechanical properties due to their unique modulation structures and interfacial properties.However,how microdefects affect their mechanical properties is still uncertain.To evaluate the influences of void location(in the crystalline layer and the Ti/Ni interface),void diameter(d)and thickness of the intermediate layer(h)on overall tensile behaviors,various types of defective Ti/Ni nanolaminates with pre-existing void are established by the molecular dynamics method in this work.The results indicate that the strength and plastic deformation mechanisms are strongly dependent on those determinants.Yield stresses of Ti/Ni nanolaminates decrease distinctly with increasing void diameter,while peak stresses with a void in the crystalline layer decrease with increasing d/h.Different void locations lead eventually to disparate initial plastic deformation carriers around the void,and various evolutions in the microstructure of the defective Ti/Ni nanolaminates.The Ti/Ni interface plays a significant role in the tensile process.The semi-coherent interface impedes new grains and lattice dislocations from passing across the interface,while the incoherent interface facilitates dislocations generating and sliding along the interface,and absorbs the dislocations moving to the interface.The results also indicate that the strain rate significantly affects the evolution of the microstructure and the tensile properties of defective Ti/Ni nanolaminates.展开更多
Development in medical intervention has significantly decreased the mortality rates for children with complex congenital heart disease(CHD)but among these survivors with complex heart disease there occurs a uniq...Development in medical intervention has significantly decreased the mortality rates for children with complex congenital heart disease(CHD)but among these survivors with complex heart disease there occurs a unique pattern of neuro-developmental and neuropsychology impairment characterized social interaction impairment,impulsive Behavior,and impaired executive functions.Presence of behavioral problem is found significantly high in pediatric population with chronic illness than children with absence of chronic illness.The sample of 200 children with congenital heart defect was selected between age 4-8 years using multistage stratified sampling.The childhood psychopathology measurement schedule(CPMS)by Dr.Savitha Malhotra was used for assessing Behavioral problems present in children with CHD.Pre-Post experimental design was used to investigate the study and the results were statistically analyzed using paired T test.The result revealed that the effectiveness of intervention program to retrain Behavior showed high significance.With increased survival rates,the aim of the intervention and research based on clinical practices gets a shift from short term medical assessment to long term assessment and intervention of morbidity.展开更多
基金The National Basic Research Program of China(No.2012CB725405)the National Natural Science Foundation of China(No.51308115)+1 种基金the Science and Technology Demonstration Project of Ministry of Transport of China(No.2015364X16030)Fundamental Research Funds for the Central Universities,the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYLX15_0153)
文摘In order to increase the accuracy of microscopic traffic flow simulation,two acceleration models are presented to simulate car-following behaviors of the lane-changing vehicle and following putative vehicle during the discretionary lanechanging preparation( DLCP) process, respectively. The proposed acceleration models can reflect vehicle interaction characteristics. Samples used for describing the starting point and the ending point of DLCP are extracted from a real NGSIM vehicle trajectory data set. The acceleration model for a lanechanging vehicle is supposed to be a linear acceleration model.The acceleration model for the following putative vehicle is constructed by referring to the optimal velocity model,in which optimal velocity is defined as a linear function of the velocity of putative leading vehicle. Similar calibration,a hypothesis test and parameter sensitivity analysis were conducted on the acceleration model of the lane-changing vehicle and following putative vehicle,respectively. The validation results of the two proposed models suggest that the training and testing errors are acceptable compared with similar works on calibrations for car following models. The parameter sensitivity analysis shows that the subtle observed error does not lead to severe variations of car-following behaviors of the lane-changing vehicle and following putative vehicle.
文摘Incidence of defects in MoSi2 rods prepared by con- tinuous extrusion is dependent on the viscosity of binder. Generally, low viscosity results in surface defects while high viscosity is responsible for inner defects. Cross-section observations indicated that the typical inner defects in sintered MoSi2 rods were large fissure cavity, multiple small holes and single small cavity, of which the characteristic ultrasonic reflection patterns have been experimentally established. Formation of the inner defects is attributed to the inhomogeneous feedstock moving behav- ior in die, which is aggravated with increasing viscosity of binder. Defect free MoSi2 rods were prepared successfully via con. tinuous extrusion by carefully controlling the viscosity of binder.
基金Data collection at SickKids was supported by the Cardiovascular Clinical Research UnitData collection by Bhavika Patel was supported by the Mach-Gaensslen Foundation of Canadathrough a summer research studentship+1 种基金Data collection by Julia Jackson was supported by a summer studentship from the CHEO Research InstituteThe analyses and manuscript preparation by Jacqueline Lee was supported by a Queen Elizabeth II Scholarship.
文摘Background:Pediatric cardiology patients often experience decreased quality of life(QoL)and higher rates of mental illness,particularly with severe disease,but the relationship between them and comparisons across diagnostic groups are limited.This mixed-methods cross-sectional study assessed the association between QoL anxiety and behavior problems among children with structural heart disease,arrhythmia,or other cardiac diagnoses.Methods:Children(6–14 years,n=76,50%female)and their parents completed measures of QoL(PedsQL),behavior(BASC-2,subset of 19 children)and anxiety(MASC-2,children 8+years).Pearson correlations/regression models examined associations between QoL,behavior and anxiety,controlling for age,sex,diagnosis and condition severity.Student t-tests compared results to published normative values.Semi-structured interviews(15 children,13 parents)examined self-and parent-reported perceptions of the patient’s emotional health.Results:Child reported social QoL(95%CI difference:−11.0,−2.1),emotional well-being(95%CI difference:−12.5,−3.8)and adjustment skills(95%CI difference:−13.9,−3.0)were significantly below published norms(p<0.05).Neither age,sex,nor diagnosis were significantly related to questionnaire responses.Compared to children with mild conditions,child and parent-reported QoL was significantly lower in children with complex conditions(np2≥0.14,p<0.05).Lower QoL was strongly associated with more internalizing problems based on both child(r=−0.78,p<0.001)and parent(r=−0.67,p<0.001)reports.Interview responses suggested emotional distress was attributed to“normal”child problems rather than the child’s cardiac problem.Conclusion:Children with complex cardiac conditions,regardless of diagnosis,had diminished QoL.Using the PedsQL in clinical settings may help identify pediatric cardiology patients experiencing emotional distress(i.e.,anxiety and depression).
基金the National Natural Science Foundation of China(Grant No.12072286)the Natural Science Foundation of Shaanxi Province(No.2020JM-095 and 2021JM-045)Fundamental Research Funds for the Central Universities(No.G2020KY05112).
文摘Metallic nanolaminated materials possess excellent mechanical properties due to their unique modulation structures and interfacial properties.However,how microdefects affect their mechanical properties is still uncertain.To evaluate the influences of void location(in the crystalline layer and the Ti/Ni interface),void diameter(d)and thickness of the intermediate layer(h)on overall tensile behaviors,various types of defective Ti/Ni nanolaminates with pre-existing void are established by the molecular dynamics method in this work.The results indicate that the strength and plastic deformation mechanisms are strongly dependent on those determinants.Yield stresses of Ti/Ni nanolaminates decrease distinctly with increasing void diameter,while peak stresses with a void in the crystalline layer decrease with increasing d/h.Different void locations lead eventually to disparate initial plastic deformation carriers around the void,and various evolutions in the microstructure of the defective Ti/Ni nanolaminates.The Ti/Ni interface plays a significant role in the tensile process.The semi-coherent interface impedes new grains and lattice dislocations from passing across the interface,while the incoherent interface facilitates dislocations generating and sliding along the interface,and absorbs the dislocations moving to the interface.The results also indicate that the strain rate significantly affects the evolution of the microstructure and the tensile properties of defective Ti/Ni nanolaminates.
文摘Development in medical intervention has significantly decreased the mortality rates for children with complex congenital heart disease(CHD)but among these survivors with complex heart disease there occurs a unique pattern of neuro-developmental and neuropsychology impairment characterized social interaction impairment,impulsive Behavior,and impaired executive functions.Presence of behavioral problem is found significantly high in pediatric population with chronic illness than children with absence of chronic illness.The sample of 200 children with congenital heart defect was selected between age 4-8 years using multistage stratified sampling.The childhood psychopathology measurement schedule(CPMS)by Dr.Savitha Malhotra was used for assessing Behavioral problems present in children with CHD.Pre-Post experimental design was used to investigate the study and the results were statistically analyzed using paired T test.The result revealed that the effectiveness of intervention program to retrain Behavior showed high significance.With increased survival rates,the aim of the intervention and research based on clinical practices gets a shift from short term medical assessment to long term assessment and intervention of morbidity.
