A set-up based on a special shadow method, pinhole method, was made and some experiments were done. The results show that this novel method is simple, easy to operate,and suitable for testing large aspherical surfaces...A set-up based on a special shadow method, pinhole method, was made and some experiments were done. The results show that this novel method is simple, easy to operate,and suitable for testing large aspherical surfaces quantitatively.展开更多
Sand/dust test is one of the key projects to examine the environmental adaptability of ordnance equipment.In order to decrease the abrasion of test facility caused by the sand/dust particles,the particles contained in...Sand/dust test is one of the key projects to examine the environmental adaptability of ordnance equipment.In order to decrease the abrasion of test facility caused by the sand/dust particles,the particles contained in the airflowneed to be reclaimed effectively.Amathematical model of Useparator is established.The flowfield and the trajectories of particles inside the separator are obtained using a numerical simulation method,and the separation efficiency and pressure drop of separator with different rows of separate components are also obtained at various flowvelocities.The simulation results indicate that the efficiency of U inertia separator is affected by the flowvelocity evidently,and a reasonably designed separator can meet the requirement of the separation efficiency in particular situation.The results can be use as reference for the design and test of sand/dust separate systems.展开更多
目的 评估基于平板电脑的数字化复杂图形测验(dCFT)软件检测遗忘型轻度认知障碍(aMCI)患者绘图表现的适用性。方法 选取2020年11月-2021年11月就诊于山西医科大学第一医院门诊的38例aMCI患者为观察组,26例认知功能正常者为对照组。两组...目的 评估基于平板电脑的数字化复杂图形测验(dCFT)软件检测遗忘型轻度认知障碍(aMCI)患者绘图表现的适用性。方法 选取2020年11月-2021年11月就诊于山西医科大学第一医院门诊的38例aMCI患者为观察组,26例认知功能正常者为对照组。两组均接受全面的神经心理测评,包括简易智力状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)、Rey复杂图形测验及各认知域量表等。同时期完成dCFT测评(dCFT软件基于平板电脑,可自动化采集多维度绘图参数),包括临摹、3 min即刻回忆及20 min延迟回忆测验。采用Pearson相关系数评估原始与简化版Rey复杂图形测验分值的相关性,采用偏相关分析dCFT参数与各认知域综合分值的相关性。结果 (1)dCFT临摹测验中,两组间参数比较差异无统计学意义(均P>0.05);即刻回忆测验中,观察组思考总时间、元素延迟时间(s)均明显长于对照组[27.15(21.49,33.94) vs. 21.85(18.26,24.81),1.99(1.36,3.62) vs. 1.32(1.03,1.99),P<0.05];延迟回忆测验中,观察组短长笔画序列过渡时间、思考总时间、完成总时间、第一笔思考时间及元素延迟时间(s)均长于对照组[1.89(1.12,3.93)vs.1.19(0.42,2.41),23.94(18.86,36.87)vs.19.93(16.59,23.00),40.30(34.83,56.21)vs.34.52(29.96,42.15),7.92(6.20,9.83)vs.5.92(5.16,8.04),1.63(1.25,2.47)vs.1.08(0.83,1.55),P<0.05],前5笔长笔画率(%)、最长笔画速度(cm/s)及每分钟笔画数(个)均低于对照组[60(40,80) vs. 80(60,100),4.65(3.53,6.07) vs. 6.00(4.54,7.13),21(18,25)vs.26(21,27),P<0.05];两组其他dCFT参数差异均无统计学意义(P>0.05)。(2)控制年龄、性别及受教育程度后,相关分析显示,短长笔画序列过渡时间与注意力及执行功能呈负相关(r=±0.292,r=±0.275,P<0.05),最长笔画速度与执行功能呈正相关(r=0.302,P<0.05),思考总时间与记忆力、注意力、执行功能、视空间能力均呈负相关(r=±0.26,r=±0.408,r=±0.448,r=±0.264,P<0.05),完成总时间与注意力、执行功能、视空间能力均呈负相关(r=±0.342,r=±0.429,r=±0.273,P<0.05),第一笔思考时间与记忆力、视空间能力均呈负相关(r=±0.365,r=±0.407,P<0.01),元素延迟时间与记忆力、注意力均呈负相关(r=±0.377,r=±0.33,P<0.01),每分钟笔画数与记忆力、注意力、执行功能、视空间能力均呈正相关(r=0.326,r=0.311,r=0.376,r=0.263,P<0.05)。结论 在复杂图形测验中,aMCI患者间隔3 min重新绘图时表现为视空间记忆受损,绘图策略尚可;间隔20 min重新绘图时记忆力及绘图策略均受到显著影响,但视觉感知在进程中受损不明显。dCFT可作为一种简便、客观的aMCI测评工具。展开更多
A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping m...A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping method into a three-dimensional fluid model,the volume production and transportation of H^(-) in the NHIS,which consists of a cylindrical driver region and a rectangular expansion chamber,are investigated self-consistently at a large input power(40 k W) and different pressures(0.3–2.0 Pa).The results indicate that with the increase of pressure,the H^(-) density at the bottom of the expansion region first increases and then decreases.In addition,the effect of the magnetic filter is examined.It is noteworthy that a significant increase in the H^(-) density is observed when the magnetic filter is introduced.As the permanent magnets move towards the driver region,the H^(-) density decreases monotonically and the asymmetry is enhanced.This study contributes to the understanding of H-distribution under various conditions and facilitates the optimization of volume production of negative hydrogen ions in the NHIS.展开更多
文摘A set-up based on a special shadow method, pinhole method, was made and some experiments were done. The results show that this novel method is simple, easy to operate,and suitable for testing large aspherical surfaces quantitatively.
文摘Sand/dust test is one of the key projects to examine the environmental adaptability of ordnance equipment.In order to decrease the abrasion of test facility caused by the sand/dust particles,the particles contained in the airflowneed to be reclaimed effectively.Amathematical model of Useparator is established.The flowfield and the trajectories of particles inside the separator are obtained using a numerical simulation method,and the separation efficiency and pressure drop of separator with different rows of separate components are also obtained at various flowvelocities.The simulation results indicate that the efficiency of U inertia separator is affected by the flowvelocity evidently,and a reasonably designed separator can meet the requirement of the separation efficiency in particular situation.The results can be use as reference for the design and test of sand/dust separate systems.
文摘目的 评估基于平板电脑的数字化复杂图形测验(dCFT)软件检测遗忘型轻度认知障碍(aMCI)患者绘图表现的适用性。方法 选取2020年11月-2021年11月就诊于山西医科大学第一医院门诊的38例aMCI患者为观察组,26例认知功能正常者为对照组。两组均接受全面的神经心理测评,包括简易智力状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)、Rey复杂图形测验及各认知域量表等。同时期完成dCFT测评(dCFT软件基于平板电脑,可自动化采集多维度绘图参数),包括临摹、3 min即刻回忆及20 min延迟回忆测验。采用Pearson相关系数评估原始与简化版Rey复杂图形测验分值的相关性,采用偏相关分析dCFT参数与各认知域综合分值的相关性。结果 (1)dCFT临摹测验中,两组间参数比较差异无统计学意义(均P>0.05);即刻回忆测验中,观察组思考总时间、元素延迟时间(s)均明显长于对照组[27.15(21.49,33.94) vs. 21.85(18.26,24.81),1.99(1.36,3.62) vs. 1.32(1.03,1.99),P<0.05];延迟回忆测验中,观察组短长笔画序列过渡时间、思考总时间、完成总时间、第一笔思考时间及元素延迟时间(s)均长于对照组[1.89(1.12,3.93)vs.1.19(0.42,2.41),23.94(18.86,36.87)vs.19.93(16.59,23.00),40.30(34.83,56.21)vs.34.52(29.96,42.15),7.92(6.20,9.83)vs.5.92(5.16,8.04),1.63(1.25,2.47)vs.1.08(0.83,1.55),P<0.05],前5笔长笔画率(%)、最长笔画速度(cm/s)及每分钟笔画数(个)均低于对照组[60(40,80) vs. 80(60,100),4.65(3.53,6.07) vs. 6.00(4.54,7.13),21(18,25)vs.26(21,27),P<0.05];两组其他dCFT参数差异均无统计学意义(P>0.05)。(2)控制年龄、性别及受教育程度后,相关分析显示,短长笔画序列过渡时间与注意力及执行功能呈负相关(r=±0.292,r=±0.275,P<0.05),最长笔画速度与执行功能呈正相关(r=0.302,P<0.05),思考总时间与记忆力、注意力、执行功能、视空间能力均呈负相关(r=±0.26,r=±0.408,r=±0.448,r=±0.264,P<0.05),完成总时间与注意力、执行功能、视空间能力均呈负相关(r=±0.342,r=±0.429,r=±0.273,P<0.05),第一笔思考时间与记忆力、视空间能力均呈负相关(r=±0.365,r=±0.407,P<0.01),元素延迟时间与记忆力、注意力均呈负相关(r=±0.377,r=±0.33,P<0.01),每分钟笔画数与记忆力、注意力、执行功能、视空间能力均呈正相关(r=0.326,r=0.311,r=0.376,r=0.263,P<0.05)。结论 在复杂图形测验中,aMCI患者间隔3 min重新绘图时表现为视空间记忆受损,绘图策略尚可;间隔20 min重新绘图时记忆力及绘图策略均受到显著影响,但视觉感知在进程中受损不明显。dCFT可作为一种简便、客观的aMCI测评工具。
基金supported by the National Key R&D Program of China (No. 2017YFE0300106)National Natural Science Foundation of China (Nos. 11935005 and 12075049)the Fundamental Research Funds for the Central Universities(Nos. DUT21TD104 and DUT21LAB110)。
文摘A radio-frequency(RF) inductively coupled negative hydrogen ion source(NHIS) has been adopted in the China Fusion Engineering Test Reactor(CFETR) to generate negative hydrogen ions.By incorporating the level-lumping method into a three-dimensional fluid model,the volume production and transportation of H^(-) in the NHIS,which consists of a cylindrical driver region and a rectangular expansion chamber,are investigated self-consistently at a large input power(40 k W) and different pressures(0.3–2.0 Pa).The results indicate that with the increase of pressure,the H^(-) density at the bottom of the expansion region first increases and then decreases.In addition,the effect of the magnetic filter is examined.It is noteworthy that a significant increase in the H^(-) density is observed when the magnetic filter is introduced.As the permanent magnets move towards the driver region,the H^(-) density decreases monotonically and the asymmetry is enhanced.This study contributes to the understanding of H-distribution under various conditions and facilitates the optimization of volume production of negative hydrogen ions in the NHIS.
