配电线路长期暴露于自然环境下,易受强对流天气影响而发生故障。2022年4月19日午后,受大风、雷电等高影响天气影响,陇南市13条配电线路先后出现故障。利用陇南市自动气象观测站的极大风速和闪电定位数据以及风云4A(FY-4A)红外云图、探...配电线路长期暴露于自然环境下,易受强对流天气影响而发生故障。2022年4月19日午后,受大风、雷电等高影响天气影响,陇南市13条配电线路先后出现故障。利用陇南市自动气象观测站的极大风速和闪电定位数据以及风云4A(FY-4A)红外云图、探空资料、多普勒天气雷达等资料,对此次强对流天气过程及其对电网影响进行分析。结果表明:(1)此次强对流天气以雷电、雷暴大风天气为主,西和、礼县、武都、康县等县(区)出现大面积用户停电和电力负荷损失等不利影响。(2)强对流发展主要受高原槽和切变线共同影响,在“上冷下暖”的大气层结不稳定条件下,由地面辐合线触发较强的雷暴大风天气;卫星云图和雷达回波也显示对流云团的发生发展与地面雷暴大风相吻合。(3)陇南市配电线路故障范围分布与强对流天气发生时间和过境路径基本一致,利用逐10 min极大风速和闪电定位数据,探讨得出当极大风速值超过15.0 m·s^(-1)、或正地闪电流强度超过43 k A、或负地闪电流强度超过26 k A时,配电线路发生故障的可能性较大。展开更多
目的探讨脂肪间充质干细胞对卵巢早衰小鼠卵巢内分泌功能及颗粒细胞凋亡的影响。方法无特定病原体(specific pathogen free,SPF)级昆明种小鼠36只,将其采用随机数字表法分为3组,即假手术组、卵巢早衰组以及脂肪间充质干细胞组,每组各12...目的探讨脂肪间充质干细胞对卵巢早衰小鼠卵巢内分泌功能及颗粒细胞凋亡的影响。方法无特定病原体(specific pathogen free,SPF)级昆明种小鼠36只,将其采用随机数字表法分为3组,即假手术组、卵巢早衰组以及脂肪间充质干细胞组,每组各12只。卵巢早衰组以及脂肪间充质干细胞组小鼠腹腔注射环磷酰胺和白消安建立卵巢早衰模型,假手术组小鼠腹腔注射0.9%氯化钠溶液。脂肪间充质干细胞组小鼠于造模成功后第1天起每7天经尾静脉注射1ml浓度为1.0×10^(9)/L脂肪间充质干细胞悬液,共注射4次。比较造模前1天、造模成功后14天和造模成功后28天3组小鼠血清雌二醇、孕酮、促卵泡生成素、黄体生成素以及抑制素B水平变化,并比较治疗后3组小鼠对卵巢病理损伤的影响和卵巢中颗粒细胞的凋亡。结果造模成功后14天,卵巢早衰组以及脂肪间充质干细胞组小鼠的血清雌二醇、孕酮以及抑制素B水平均低于假手术组(P均<0.05),促卵泡生成素、黄体生成素水平均高于假手术组(P均<0.05),且造模成功后28天卵巢早衰组小鼠的血清雌二醇、孕酮以及抑制素B水平均低于脂肪间充质干细胞组(33.57±1.98ng/L vs 41.66±1.70ng/L,t=-5.945,P<0.05;7.57±1.12ng/L vs 10.84±1.12ng/L,t=-4.056,P<0.05;110.58±4.18ng/L vs 129.86±2.97ng/L,t=-7.394,P<0.05),促卵泡生成素、黄体生成素水平均高于脂肪间充质干细胞组(5.15±0.20IU/L vs 3.61±0.12IU/L,t=10.401,P<0.05;510.94±7.11IU/L vs 410.14±5.45IU/L,t=22.407,P<0.05)。经脂肪间充质干细胞移植治疗后,卵巢早衰小鼠卵巢病理损伤明显减轻,且凋亡的颗粒细胞数量明显减少。结论脂肪间充质干细胞通过改善卵巢早衰小鼠卵巢内分泌功能,减少颗粒细胞凋亡,对卵巢早衰具有治疗作用。展开更多
Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speed...Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speeded-up robust features algorithm,binary robust invariant scalable keypoints algorithm,and oriented fast and rotated brief algorithm.The performance of these algorithms was estimated in terms of matching accuracy,feature point richness,and running time.The experiment result showed that no algorithm achieved high accuracy while keeping low running time,and all algorithms are not suitable for image feature extraction and matching of augmented solar images.To solve this problem,an improved method was proposed by using two-frame matching to utilize the accuracy advantage of the scale-invariant feature transform algorithm and the speed advantage of the oriented fast and rotated brief algorithm.Furthermore,our method and the four representative algorithms were applied to augmented solar images.Our application experiments proved that our method achieved a similar high recognition rate to the scale-invariant feature transform algorithm which is significantly higher than other algorithms.Our method also obtained a similar low running time to the oriented fast and rotated brief algorithm,which is significantly lower than other algorithms.展开更多
Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated var...Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated variables at the same time.However,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these variables.For space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these variables.The volume data associated with each variable is divided into disjoint blocks of size 43 initially.The blocks are represented as two levels,a mean level and a detail level.The variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail level.To both global levels,a splitting based on a principal component analysis is applied to compute initial codebooks.Then,LBG algorithm is conducted for codebook refinement and quantization.We further take advantage of progressive rendering based on GPU for real-time interactive visualization.Our method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton flux.The results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.展开更多
文摘配电线路长期暴露于自然环境下,易受强对流天气影响而发生故障。2022年4月19日午后,受大风、雷电等高影响天气影响,陇南市13条配电线路先后出现故障。利用陇南市自动气象观测站的极大风速和闪电定位数据以及风云4A(FY-4A)红外云图、探空资料、多普勒天气雷达等资料,对此次强对流天气过程及其对电网影响进行分析。结果表明:(1)此次强对流天气以雷电、雷暴大风天气为主,西和、礼县、武都、康县等县(区)出现大面积用户停电和电力负荷损失等不利影响。(2)强对流发展主要受高原槽和切变线共同影响,在“上冷下暖”的大气层结不稳定条件下,由地面辐合线触发较强的雷暴大风天气;卫星云图和雷达回波也显示对流云团的发生发展与地面雷暴大风相吻合。(3)陇南市配电线路故障范围分布与强对流天气发生时间和过境路径基本一致,利用逐10 min极大风速和闪电定位数据,探讨得出当极大风速值超过15.0 m·s^(-1)、或正地闪电流强度超过43 k A、或负地闪电流强度超过26 k A时,配电线路发生故障的可能性较大。
文摘目的探讨脂肪间充质干细胞对卵巢早衰小鼠卵巢内分泌功能及颗粒细胞凋亡的影响。方法无特定病原体(specific pathogen free,SPF)级昆明种小鼠36只,将其采用随机数字表法分为3组,即假手术组、卵巢早衰组以及脂肪间充质干细胞组,每组各12只。卵巢早衰组以及脂肪间充质干细胞组小鼠腹腔注射环磷酰胺和白消安建立卵巢早衰模型,假手术组小鼠腹腔注射0.9%氯化钠溶液。脂肪间充质干细胞组小鼠于造模成功后第1天起每7天经尾静脉注射1ml浓度为1.0×10^(9)/L脂肪间充质干细胞悬液,共注射4次。比较造模前1天、造模成功后14天和造模成功后28天3组小鼠血清雌二醇、孕酮、促卵泡生成素、黄体生成素以及抑制素B水平变化,并比较治疗后3组小鼠对卵巢病理损伤的影响和卵巢中颗粒细胞的凋亡。结果造模成功后14天,卵巢早衰组以及脂肪间充质干细胞组小鼠的血清雌二醇、孕酮以及抑制素B水平均低于假手术组(P均<0.05),促卵泡生成素、黄体生成素水平均高于假手术组(P均<0.05),且造模成功后28天卵巢早衰组小鼠的血清雌二醇、孕酮以及抑制素B水平均低于脂肪间充质干细胞组(33.57±1.98ng/L vs 41.66±1.70ng/L,t=-5.945,P<0.05;7.57±1.12ng/L vs 10.84±1.12ng/L,t=-4.056,P<0.05;110.58±4.18ng/L vs 129.86±2.97ng/L,t=-7.394,P<0.05),促卵泡生成素、黄体生成素水平均高于脂肪间充质干细胞组(5.15±0.20IU/L vs 3.61±0.12IU/L,t=10.401,P<0.05;510.94±7.11IU/L vs 410.14±5.45IU/L,t=22.407,P<0.05)。经脂肪间充质干细胞移植治疗后,卵巢早衰小鼠卵巢病理损伤明显减轻,且凋亡的颗粒细胞数量明显减少。结论脂肪间充质干细胞通过改善卵巢早衰小鼠卵巢内分泌功能,减少颗粒细胞凋亡,对卵巢早衰具有治疗作用。
基金Supported by the Key Research Program of the Chinese Academy of Sciences(ZDRE-KT-2021-3)。
文摘Augmented solar images were used to research the adaptability of four representative image extraction and matching algorithms in space weather domain.These include the scale-invariant feature transform algorithm,speeded-up robust features algorithm,binary robust invariant scalable keypoints algorithm,and oriented fast and rotated brief algorithm.The performance of these algorithms was estimated in terms of matching accuracy,feature point richness,and running time.The experiment result showed that no algorithm achieved high accuracy while keeping low running time,and all algorithms are not suitable for image feature extraction and matching of augmented solar images.To solve this problem,an improved method was proposed by using two-frame matching to utilize the accuracy advantage of the scale-invariant feature transform algorithm and the speed advantage of the oriented fast and rotated brief algorithm.Furthermore,our method and the four representative algorithms were applied to augmented solar images.Our application experiments proved that our method achieved a similar high recognition rate to the scale-invariant feature transform algorithm which is significantly higher than other algorithms.Our method also obtained a similar low running time to the oriented fast and rotated brief algorithm,which is significantly lower than other algorithms.
基金the Key Research Program of the Chinese Academy of Sciences(ZDRE-KT-2021-3)。
文摘Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated variables at the same time.However,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these variables.For space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these variables.The volume data associated with each variable is divided into disjoint blocks of size 43 initially.The blocks are represented as two levels,a mean level and a detail level.The variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail level.To both global levels,a splitting based on a principal component analysis is applied to compute initial codebooks.Then,LBG algorithm is conducted for codebook refinement and quantization.We further take advantage of progressive rendering based on GPU for real-time interactive visualization.Our method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton flux.The results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.
