This study investigates the mechanical properties of Q235B steel through quasi-static tests at both room temperature and elevated temperature.The initial values of the Johnson-Cook model parameters are determined usin...This study investigates the mechanical properties of Q235B steel through quasi-static tests at both room temperature and elevated temperature.The initial values of the Johnson-Cook model parameters are determined using a fitting method.The global response surface algorithm is employed to optimize and calibrate the Johnson-Cook model parameters for Q235B steel under both room temperature and elevated temperature conditions.A simulation model is established at room temperature,and the simulated mechanical performance curves for displacement and stress are monitored.Multiple optimization algorithms are applied to optimize and calibrate the model parameters at room temperature.The global response surface algorithm is identified as the most suitable algorithm for this optimization problem.Sensitivity analysis is conducted to explore the impact of model parameters on the objective function.The analysis indicates that the optimized material model better fits the experimental values,aligning more closely with the actual test results of material strain mechanisms over a wide temperature range.展开更多
Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to t...Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to two different antiepileptic drugs, oxcarbazepine（OXC） and phenobabital（PB）. In addition, we genotyped HLA-B 1511 in a case of CBZ-induced SJS with genotype negative for HLA-B 1502. The presence of HLA-B 1502 was determined using polymerase chain reaction with sequence-specific primers（PCR-SSP）. Moreover, we genotyped HLA-B 1502 in 17 cases of antiepileptic drugs（AEDs）-induced cutaneous adverse drug reactions（cADRs）, in comparison with AEDs-tolerant（n=32） and normal controls（n=38） in the central region of China. The data showed that HLA-B 1502 was positive in 5 of 6 cases of AEDs-induced SJS（4 CBZ, 1 OXC and 1 PB）, which was significantly more frequent than AEDs-tolerant（2/32, 18 CBZ, 6 PB and 8 OXC） and normal controls（3/38）. Compared with AEDs-tolerant and normal controls, the OR for patients carrying the HLA-B 1502 with AEDs-induced SJS was 6.25（95% CI： 1.06–36.74） and 4.86（95% CI： 1.01–23.47）. The sensitivity and specificity of HLA-B 1502 for prediction of AEDs-induced SJS were 71.4%. The sensitivity and specificity of HLA-B 1502 for prediction of CBZ-induced SJS were 60% and 94%. HLA-B 1502 was not found in 11 children with maculopapular exanthema（MPE）（n=9） and hypersensitivity syndrome（HSS）（n=2）. However, we also found one case of CBZ-induced SJS who was negative for HLA-B 1502 but carried HLA-B 1511. It was suggested that the association between the CBZ-induced SJS and HLA-B 1502 allele in Han Chinese children can extend to other aromatic AEDs including OXC and PB related SJS. HLA-B 1511 may be a risk factor for some patients with CBZ-induced SJS negative for HLA-B 1502.展开更多
The diameter distribution of trees in a stand provides the basis for determining the stand’s ecological and economic value,its structure and stability and appropriate management practices.Scots pine(Pinus sylvestris ...The diameter distribution of trees in a stand provides the basis for determining the stand’s ecological and economic value,its structure and stability and appropriate management practices.Scots pine(Pinus sylvestris L.)is one of the most common and important conifers in Turkey,so a well-planned management schedule is critical.Diameter distribution models to accurately describe the stand structure help improve management strategies,but developing reliable models requires a deep understanding of the growth,output and constraints of the forests.The most important information derived by diameter distribution models is primary data on horizontal stand structure for each diameter class of trees:basal area and volume per unit area.These predictions are required to estimate the range of products and predicted volume and yield from a forest stand.Here,to construct an accurate,reliable diameter distribution model for natural Scots pine stands in the Türkmen Mountain region,we used Johnson’s SBdistribution to represent the empirical diameter distributions of the stands using ground-based measurements from 55 sample plots that included1219 trees in natural distribution zones of the forests.As an alternative,nonparametric approach,which does not require any predefined function,an artificial intelligence model was constructed based on support vector machine methodology.An error index was calculated to evaluate the results.Overall,both Johnson’s SB probability density function with a three-parameter recovery approach and the support vector regression methodology provided reliable estimates of the diameter distribution of these stands.展开更多
文摘This study investigates the mechanical properties of Q235B steel through quasi-static tests at both room temperature and elevated temperature.The initial values of the Johnson-Cook model parameters are determined using a fitting method.The global response surface algorithm is employed to optimize and calibrate the Johnson-Cook model parameters for Q235B steel under both room temperature and elevated temperature conditions.A simulation model is established at room temperature,and the simulated mechanical performance curves for displacement and stress are monitored.Multiple optimization algorithms are applied to optimize and calibrate the model parameters at room temperature.The global response surface algorithm is identified as the most suitable algorithm for this optimization problem.Sensitivity analysis is conducted to explore the impact of model parameters on the objective function.The analysis indicates that the optimized material model better fits the experimental values,aligning more closely with the actual test results of material strain mechanisms over a wide temperature range.
基金supported by a grant from Clinical Scientific Research of Wuhan Sanitary Bureau(No.WX11C26)research fund from Janssen Research Council of China(No.JRCC2011-01)
文摘Previous studies have demonstrated a strong association between carbamazepine（CBZ）-induced Stevens-Johnson syndrome（SJS） and HLA-B 1502 in Han Chinese. Here, we extended the study of HLA-B 1502 susceptibility to two different antiepileptic drugs, oxcarbazepine（OXC） and phenobabital（PB）. In addition, we genotyped HLA-B 1511 in a case of CBZ-induced SJS with genotype negative for HLA-B 1502. The presence of HLA-B 1502 was determined using polymerase chain reaction with sequence-specific primers（PCR-SSP）. Moreover, we genotyped HLA-B 1502 in 17 cases of antiepileptic drugs（AEDs）-induced cutaneous adverse drug reactions（cADRs）, in comparison with AEDs-tolerant（n=32） and normal controls（n=38） in the central region of China. The data showed that HLA-B 1502 was positive in 5 of 6 cases of AEDs-induced SJS（4 CBZ, 1 OXC and 1 PB）, which was significantly more frequent than AEDs-tolerant（2/32, 18 CBZ, 6 PB and 8 OXC） and normal controls（3/38）. Compared with AEDs-tolerant and normal controls, the OR for patients carrying the HLA-B 1502 with AEDs-induced SJS was 6.25（95% CI： 1.06–36.74） and 4.86（95% CI： 1.01–23.47）. The sensitivity and specificity of HLA-B 1502 for prediction of AEDs-induced SJS were 71.4%. The sensitivity and specificity of HLA-B 1502 for prediction of CBZ-induced SJS were 60% and 94%. HLA-B 1502 was not found in 11 children with maculopapular exanthema（MPE）（n=9） and hypersensitivity syndrome（HSS）（n=2）. However, we also found one case of CBZ-induced SJS who was negative for HLA-B 1502 but carried HLA-B 1511. It was suggested that the association between the CBZ-induced SJS and HLA-B 1502 allele in Han Chinese children can extend to other aromatic AEDs including OXC and PB related SJS. HLA-B 1511 may be a risk factor for some patients with CBZ-induced SJS negative for HLA-B 1502.
基金supported by Turkish General Directorate of Forestry。
文摘The diameter distribution of trees in a stand provides the basis for determining the stand’s ecological and economic value,its structure and stability and appropriate management practices.Scots pine(Pinus sylvestris L.)is one of the most common and important conifers in Turkey,so a well-planned management schedule is critical.Diameter distribution models to accurately describe the stand structure help improve management strategies,but developing reliable models requires a deep understanding of the growth,output and constraints of the forests.The most important information derived by diameter distribution models is primary data on horizontal stand structure for each diameter class of trees:basal area and volume per unit area.These predictions are required to estimate the range of products and predicted volume and yield from a forest stand.Here,to construct an accurate,reliable diameter distribution model for natural Scots pine stands in the Türkmen Mountain region,we used Johnson’s SBdistribution to represent the empirical diameter distributions of the stands using ground-based measurements from 55 sample plots that included1219 trees in natural distribution zones of the forests.As an alternative,nonparametric approach,which does not require any predefined function,an artificial intelligence model was constructed based on support vector machine methodology.An error index was calculated to evaluate the results.Overall,both Johnson’s SB probability density function with a three-parameter recovery approach and the support vector regression methodology provided reliable estimates of the diameter distribution of these stands.
