G-DINA(the generalizeddeterministic input,noisy and gate)模型限制条件少,应用范围广,满足大量心理与教育评估测验数据的要求。研究提出一种适用于G-DINA等模型的同时标定新题Q矩阵与项目参数的认知诊断计算机化自适应测验(CD-CAT)...G-DINA(the generalizeddeterministic input,noisy and gate)模型限制条件少,应用范围广,满足大量心理与教育评估测验数据的要求。研究提出一种适用于G-DINA等模型的同时标定新题Q矩阵与项目参数的认知诊断计算机化自适应测验(CD-CAT)在线标定新方法SCADOCM,以期促进CD-CAT在实践中的推广与应用。本研究分别基于模拟题库以及真实题库进行研究,结果表明:相比传统的SIE方法,SCADOCM在各实验条件下均具有较为理想的标定精度与标定效率,应用前景较好;SIE方法不适用于饱和的G-DINA等模型,其各实验条件下的Q矩阵标定精度均较低。展开更多
To investigate the seismic response of the steel-strip reinforced soil retaining wall with fullheight rigid facing in terms of the acceleration in the backfill, dynamic earth pressure in the backfill, the displacement...To investigate the seismic response of the steel-strip reinforced soil retaining wall with fullheight rigid facing in terms of the acceleration in the backfill, dynamic earth pressure in the backfill, the displacements on the facing and the dynamic reinforcement strain distribution under different peak acceleration, a large 1-g shaking table test was performed on a reduced-scale reinforced-earth retaining wall model. It was observed that the acceleration response in non-strip region is greater than that in potential fracture region which is similar with the stability region under small earthquake,while the acceleration response in potential fracture region is greater than that in stability region in middle-upper of the wall under moderately strong earthquakes. The potential failure model of the rigid wall is rotating around the wall toe. It also was discovered that the Fourier spectra produced by the inputting white noises after seismic wave presents double peaks, rather than original single peak, and the frequency of the second peak trends to increase with increasing the PGA(peak ground amplitude) of the excitation which is greater than 0.4 g. Additionally,the non-liner distribution of strip strain along the strips was observed, and the distribution trend was not constant in different row. Soil pressure peak value in stability region is larger than that in potential fracture region. The wall was effective under 0.1 g-0.3 g seismic wave according to the analyses of the facing displacement and relative density. Also, it was discovered that the potential failure surface is corresponds to that in design code, but the area is larger. The results from the study can provide guidance for a more rational design of reinforced earth retaining walls with full-height rigid facing in the earthquake zone.展开更多
ZTE USA, Inc., a wholly owned subsidiary of ZTE Corporation, announced the successful completion of field tests for its 10G Ethernet Passive Optical Network （EPON） solution with a leading U.S. Multiple System Operat...ZTE USA, Inc., a wholly owned subsidiary of ZTE Corporation, announced the successful completion of field tests for its 10G Ethernet Passive Optical Network （EPON） solution with a leading U.S. Multiple System Operator （MSO） on May 12, 2010. ZTE＇s highly integrated network equipment enables MSOs to compete with the telecommunication operators in the overlay market, maximizing revenues on new services,展开更多
In this research,two shake table experiments were conducted to study the effects of non-liquefiable crust layer and superstructure mass on the responses of two sets of 22 pile groups to liquefactioninduced lateral spr...In this research,two shake table experiments were conducted to study the effects of non-liquefiable crust layer and superstructure mass on the responses of two sets of 22 pile groups to liquefactioninduced lateral spreading.In this regard,an inclined base layer overlain by a very loose liquefiable layer was constructed in both models;while only in one model,a non-liquefiable crust layer was built.A lumped mass,being representative of a superstructure,was attached to the cap of one pile group in both models.The models were fully instrumented with various sensors,including acceleration,displacement,and pore water pressure transducers.Also,the piles were instrumented with pair strain gauges to measure pure bending moments induced by cyclic and monotonic loadings associated with ground shaking and lateral spreading,respectively.The results showed that the existence of the non-liquefiable crust layer increases both the maximum and residual soil displacements at the free field and also the maximum bending moments in the piles.The results of the experiments indicated that the crust layer induces a high kinematic lateral soil pressure and force on the piles which are not present in the crustless case.The crust layer increases the pile cap displacement before liquefaction,albeit decreases it after liquefaction,due to the elastic rebound of the piles in the liquefiable layer.The crust layer postpones both liquefaction triggering and dissipation of excess pore water pressure.The existence of the superstructure mass on the pile caps decreases the acceleration amplitude of the pile caps,while increases their maximum displacement.展开更多
Based on the theoretical inference and experiment verification,a method was proposed to carry out the accelerated reliability qualification testing. First,theoretical inference was used to get the acceleration coeffic...Based on the theoretical inference and experiment verification,a method was proposed to carry out the accelerated reliability qualification testing. First,theoretical inference was used to get the acceleration coefficients of super Gauss vibration stress and temperature stress. Then, by applying these coefficients, an accelerated reliability qualification testing curve was obtained from the standard tests. Finally,the actual experiment on a digital marine control device was carried out under the proposed testing method.The experiment result shows that the proposed method can reduce the total experiment time and improve the efficiency of the reliability qualification test.展开更多
目的探讨苄星青霉素G不同用药时机治疗妊娠合并梅毒患者的效果及对母婴结局、甲苯胺红不加热血清试验(TRUST)滴度的影响。方法回顾性选取2019年1月至2021年12月临平区分娩单位的119例妊娠合并梅毒患者作为研究对象,根据苄星青霉素G用药...目的探讨苄星青霉素G不同用药时机治疗妊娠合并梅毒患者的效果及对母婴结局、甲苯胺红不加热血清试验(TRUST)滴度的影响。方法回顾性选取2019年1月至2021年12月临平区分娩单位的119例妊娠合并梅毒患者作为研究对象,根据苄星青霉素G用药时机分为孕早期组(≤13+6周,n=40)、孕中期组(14~27+6周,n=55)和孕晚期组(≥28周,n=24)。三组均给予苄星青霉素G进行治疗,均连续治疗2个疗程。比较三组治疗前后的氧化应激水平,产妇、新生儿TRUST滴度及母婴结局。结果与治疗前比较,治疗后三组血清隐性氧化蛋白产物(AOPP)、丙二醛(MDA)水平均降低,孕早期组均低于孕晚期组、孕中期组;与治疗前比较,治疗后三组血清超氧化物歧化酶(SOD)水平均升高,孕早期组高于孕晚期组、孕中期组;与孕晚期组、孕中期组比较,孕早期组患者及新生儿的TRUST阴性率、新生儿体重、出生后5 min Apgar评分均升高,先天梅毒儿、早产发生率均较低,差异具有统计学意义(P<0.05)。结论在孕早期采用苄星青霉素G治疗妊娠合并梅毒患者可有效改善其氧化应激水平,改善妊娠结局和围产儿的预后情况,提高产妇及新生儿的TRUST阴性率,减少先天梅毒儿、早产的发生。展开更多
文摘G-DINA(the generalizeddeterministic input,noisy and gate)模型限制条件少,应用范围广,满足大量心理与教育评估测验数据的要求。研究提出一种适用于G-DINA等模型的同时标定新题Q矩阵与项目参数的认知诊断计算机化自适应测验(CD-CAT)在线标定新方法SCADOCM,以期促进CD-CAT在实践中的推广与应用。本研究分别基于模拟题库以及真实题库进行研究,结果表明:相比传统的SIE方法,SCADOCM在各实验条件下均具有较为理想的标定精度与标定效率,应用前景较好;SIE方法不适用于饱和的G-DINA等模型,其各实验条件下的Q矩阵标定精度均较低。
基金founded by the National Natural Science Foundation of China(Grant No.51708163)Research Program of the Ministry of Transport of the People’s Republic of China(Grant No.2013318800020)Doctoral Innovation Fund Program of Southwest Jiaotong University(Grant No.D-CX201703)
文摘To investigate the seismic response of the steel-strip reinforced soil retaining wall with fullheight rigid facing in terms of the acceleration in the backfill, dynamic earth pressure in the backfill, the displacements on the facing and the dynamic reinforcement strain distribution under different peak acceleration, a large 1-g shaking table test was performed on a reduced-scale reinforced-earth retaining wall model. It was observed that the acceleration response in non-strip region is greater than that in potential fracture region which is similar with the stability region under small earthquake,while the acceleration response in potential fracture region is greater than that in stability region in middle-upper of the wall under moderately strong earthquakes. The potential failure model of the rigid wall is rotating around the wall toe. It also was discovered that the Fourier spectra produced by the inputting white noises after seismic wave presents double peaks, rather than original single peak, and the frequency of the second peak trends to increase with increasing the PGA(peak ground amplitude) of the excitation which is greater than 0.4 g. Additionally,the non-liner distribution of strip strain along the strips was observed, and the distribution trend was not constant in different row. Soil pressure peak value in stability region is larger than that in potential fracture region. The wall was effective under 0.1 g-0.3 g seismic wave according to the analyses of the facing displacement and relative density. Also, it was discovered that the potential failure surface is corresponds to that in design code, but the area is larger. The results from the study can provide guidance for a more rational design of reinforced earth retaining walls with full-height rigid facing in the earthquake zone.
文摘ZTE USA, Inc., a wholly owned subsidiary of ZTE Corporation, announced the successful completion of field tests for its 10G Ethernet Passive Optical Network （EPON） solution with a leading U.S. Multiple System Operator （MSO） on May 12, 2010. ZTE＇s highly integrated network equipment enables MSOs to compete with the telecommunication operators in the overlay market, maximizing revenues on new services,
基金support by the Construction and Development of Transportation Infrastructures Company affiliated with the Ministry of Roads and Urban Development of Iran and partial financial support granted by the Research Deputy of the Sharif University of Technology are acknowledged.
文摘In this research,two shake table experiments were conducted to study the effects of non-liquefiable crust layer and superstructure mass on the responses of two sets of 22 pile groups to liquefactioninduced lateral spreading.In this regard,an inclined base layer overlain by a very loose liquefiable layer was constructed in both models;while only in one model,a non-liquefiable crust layer was built.A lumped mass,being representative of a superstructure,was attached to the cap of one pile group in both models.The models were fully instrumented with various sensors,including acceleration,displacement,and pore water pressure transducers.Also,the piles were instrumented with pair strain gauges to measure pure bending moments induced by cyclic and monotonic loadings associated with ground shaking and lateral spreading,respectively.The results showed that the existence of the non-liquefiable crust layer increases both the maximum and residual soil displacements at the free field and also the maximum bending moments in the piles.The results of the experiments indicated that the crust layer induces a high kinematic lateral soil pressure and force on the piles which are not present in the crustless case.The crust layer increases the pile cap displacement before liquefaction,albeit decreases it after liquefaction,due to the elastic rebound of the piles in the liquefiable layer.The crust layer postpones both liquefaction triggering and dissipation of excess pore water pressure.The existence of the superstructure mass on the pile caps decreases the acceleration amplitude of the pile caps,while increases their maximum displacement.
文摘Based on the theoretical inference and experiment verification,a method was proposed to carry out the accelerated reliability qualification testing. First,theoretical inference was used to get the acceleration coefficients of super Gauss vibration stress and temperature stress. Then, by applying these coefficients, an accelerated reliability qualification testing curve was obtained from the standard tests. Finally,the actual experiment on a digital marine control device was carried out under the proposed testing method.The experiment result shows that the proposed method can reduce the total experiment time and improve the efficiency of the reliability qualification test.
文摘目的探讨苄星青霉素G不同用药时机治疗妊娠合并梅毒患者的效果及对母婴结局、甲苯胺红不加热血清试验(TRUST)滴度的影响。方法回顾性选取2019年1月至2021年12月临平区分娩单位的119例妊娠合并梅毒患者作为研究对象,根据苄星青霉素G用药时机分为孕早期组(≤13+6周,n=40)、孕中期组(14~27+6周,n=55)和孕晚期组(≥28周,n=24)。三组均给予苄星青霉素G进行治疗,均连续治疗2个疗程。比较三组治疗前后的氧化应激水平,产妇、新生儿TRUST滴度及母婴结局。结果与治疗前比较,治疗后三组血清隐性氧化蛋白产物(AOPP)、丙二醛(MDA)水平均降低,孕早期组均低于孕晚期组、孕中期组;与治疗前比较,治疗后三组血清超氧化物歧化酶(SOD)水平均升高,孕早期组高于孕晚期组、孕中期组;与孕晚期组、孕中期组比较,孕早期组患者及新生儿的TRUST阴性率、新生儿体重、出生后5 min Apgar评分均升高,先天梅毒儿、早产发生率均较低,差异具有统计学意义(P<0.05)。结论在孕早期采用苄星青霉素G治疗妊娠合并梅毒患者可有效改善其氧化应激水平,改善妊娠结局和围产儿的预后情况,提高产妇及新生儿的TRUST阴性率,减少先天梅毒儿、早产的发生。
