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时序数据图像化:战术意图识别及可移植框架
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作者 宋亚飞 李乐民 +2 位作者 权文 倪鹏 王科 《通信学报》 EI CSCD 北大核心 2024年第8期149-165,共17页
通过将时序编码为图像,提出了一种结合曲线滤波技术和EfficientNetV2图像识别网络的鲁棒且可移植的战术意图识别框架。曲线滤波技术可以有效地减少大量时域特征、模型参数和训练时间的冗余,基于此,提出了一种改进的格拉姆角场方法将时... 通过将时序编码为图像,提出了一种结合曲线滤波技术和EfficientNetV2图像识别网络的鲁棒且可移植的战术意图识别框架。曲线滤波技术可以有效地减少大量时域特征、模型参数和训练时间的冗余,基于此,提出了一种改进的格拉姆角场方法将时序编码为图像,提高了卷积神经网络的特征提取能力。EfficientNetV2网络能够有效地处理意图图像,并成为预训练模型,使得在不同系统之间进行迁移学习成为可能。实验结果表明,所提框架相对于机器学习及深度学习等方法提高了0.99%以上的准确率,具有更好的性能、可扩展性、鲁棒性和可迁移性。 展开更多
关键词 时序编码 意图识别 图像分类 曲线滤波 格拉姆角场 EfficientNetV2
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基于PSBC机制的指挥控制体系
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作者 李山 权文 +1 位作者 宋敏 李昉 《火力与指挥控制》 CSCD 北大核心 2024年第2期48-55,共8页
面对当今我国周边复杂严峻的战略态势和信息化条件下的联合作战样式,通过分析现代战争“明战”“暗战”“观战”相结合的战争形态,以及基于PREA环的指挥控制体系,引出了复杂战争系统概念。根据复杂战争系统中亟待解决的问题,引入ACP方... 面对当今我国周边复杂严峻的战略态势和信息化条件下的联合作战样式,通过分析现代战争“明战”“暗战”“观战”相结合的战争形态,以及基于PREA环的指挥控制体系,引出了复杂战争系统概念。根据复杂战争系统中亟待解决的问题,引入ACP方法与区块链理论,提出战场PSBC机制,以期实现对战场的高效指挥控制。并采用BDI方式对PSBC机制进行建模,以近距空中支援为例,详细介绍PSBC机制BDI建模方法。最后提出了实现PSBC以及相应BDI建模的关键技术需求。 展开更多
关键词 指挥与控制 平行系统 ACP方法 区块链 BDI
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基于改进D-S理论的多时刻空中目标威胁评估
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作者 李山 权文 +2 位作者 李昉 苏力德 黄呈祥 《电光与控制》 CSCD 北大核心 2024年第3期48-52,共5页
针对单时刻空中目标威胁评估存在的抗干扰能力弱、可靠性不足等问题,建立一种基于改进D-S证据理论的多时刻空中目标威胁评估模型。首先,根据空战时间线,定义多时刻空中目标威胁评估时段范围;然后,在单时刻空中目标威胁等级概率分配基础... 针对单时刻空中目标威胁评估存在的抗干扰能力弱、可靠性不足等问题,建立一种基于改进D-S证据理论的多时刻空中目标威胁评估模型。首先,根据空战时间线,定义多时刻空中目标威胁评估时段范围;然后,在单时刻空中目标威胁等级概率分配基础上,利用D-S证据理论融合各时刻证据信息;同时,针对D-S证据理论不能处理高冲突证据的弊端及其现有改进方法计算量较大的不足,引入偏移度的概念,确定各时刻证据源权重,对加权证据进行D-S融合。数值算例表明,该模型算法复杂度低;能有效处理波动数据、稳定性强,并且可减弱高冲突证据融合对威胁评估带来的不利影响,为最终决策提供了更准确的判别依据。 展开更多
关键词 威胁评估 空中目标 D-S证据理论 偏移度
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FGF signaling modulates mechanotransduction/WNT signaling in progenitors during tooth root development
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作者 Fei Pei Tingwei Guo +6 位作者 Mingyi Zhang Li Ma Junjun Jing Jifan Feng Thach-Vu Ho quan wen Yang Chai 《Bone Research》 SCIE CAS CSCD 2024年第3期582-594,共13页
Stem/progenitor cells differentiate into different cell lineages during organ development and morphogenesis.Signaling pathway networks and mechanotransduction are important factors to guide the lineage commitment of s... Stem/progenitor cells differentiate into different cell lineages during organ development and morphogenesis.Signaling pathway networks and mechanotransduction are important factors to guide the lineage commitment of stem/progenitor cells during craniofacial tissue morphogenesis. 展开更多
关键词 PROGENITOR MEC FACIAL
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基于随机历史集的有反馈MSIF目标识别方法
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作者 李山 权文 苏力德 《火力与指挥控制》 CSCD 北大核心 2024年第4期130-135,共6页
为提高复杂战场环境下的目标识别准确度,提出了一种分布式MSIF模型,并通过加入反馈信息流,对时域内的序贯信息进行处理。以经典D-S证据理论为基础,针对其不能处理高冲突证据的弊端,采用费雪耶兹洗牌方法,置乱泛传感器矩阵中的信息排序,... 为提高复杂战场环境下的目标识别准确度,提出了一种分布式MSIF模型,并通过加入反馈信息流,对时域内的序贯信息进行处理。以经典D-S证据理论为基础,针对其不能处理高冲突证据的弊端,采用费雪耶兹洗牌方法,置乱泛传感器矩阵中的信息排序,生成随机历史集,并随着运算次数增加,算法反复迭代。通过改进算法,修正了由于高冲突证据过早出现所带来的识别结果偏差。数值算例表明,该方法既能提高信息利用率,同时可克服信息先入性陷阱的影响,准确度较高,且计算量较小,能有效减轻系统负担,适合MSIF目标识别中的大数据量处理。 展开更多
关键词 目标识别 证据融合 MSIF 随机历史集
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基于改进NSGA-Ⅱ算法的双运输机重装空投研究 被引量:2
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作者 李山 权文 +2 位作者 苏力德 黄呈祥 李晨昕 《电光与控制》 CSCD 北大核心 2023年第10期40-45,共6页
为了提高空降部队突击突防能力,对双运输机重装空投编队多目标规划问题进行研究。首先,基于分离法分析重装空投货台运动过程,通过欧拉迭代思想构建货台动力学模型。然后,考虑到前机尾涡对后机影响,构建了双运输机编队空间位置模型。为... 为了提高空降部队突击突防能力,对双运输机重装空投编队多目标规划问题进行研究。首先,基于分离法分析重装空投货台运动过程,通过欧拉迭代思想构建货台动力学模型。然后,考虑到前机尾涡对后机影响,构建了双运输机编队空间位置模型。为确定双机编队位置关系的最优解,采用改进后的NSGA-II算法,引入支配强度、优化精英策略、种群等级交叉系数以及高斯变异算子,同时基于方差表示拥挤度,计算出最终结果。仿真实验数据表明,优化后的算法不仅能够提升双运输机编队飞行安全性,而且使得空投点更加密集、空投精度更高。 展开更多
关键词 重装空投 运输机编队 NSGA-Ⅱ
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Washed microbiota transplantation stopped the deterioration of amyotrophic lateral sclerosis:The first case report and narrative review
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作者 Gaochen Lu quan wen +2 位作者 Bota Cui Qianqian Li Faming Zhang 《The Journal of Biomedical Research》 CAS CSCD 2023年第1期69-76,共8页
Amyotrophic lateral sclerosis(ALS) is known as a progressive paralysis disorder characterized by degeneration of upper and lower motor neurons, and has an average survival time of three to five years. Growing evidence... Amyotrophic lateral sclerosis(ALS) is known as a progressive paralysis disorder characterized by degeneration of upper and lower motor neurons, and has an average survival time of three to five years. Growing evidence has suggested a bidirectional link between gut microbiota and neurodegeneration. Here we aimed to report one female case with ALS, who benefited from washed microbiota transplantation(WMT), an improved fecal microbiota transplantation(FMT), through a transendoscopic enteral tube during a 12-month follow-up. Notedly, the accidental scalp trauma the patient suffered later was treated with prescribed antibiotics that caused ALS deterioration. The subsequent rescue WMTs successfully stopped the progression of the disease with a quick improvement. The plateaus and reversals occurred during the whole course of WMT. The stool and blood samples from the first WMT to the last were collected for dynamic microbial and metabolomic analysis. We observed the microbial and metabolomic changing trend consistent with the disease status. This case report for the first time shows the direct clinical evidence on using WMT for treating ALS, indicating that WMT may be the novel treatment strategy for controlling this so-called incurable disease. 展开更多
关键词 fecal microbiota transplant MICROBIOME efficacy NEURODEGENERATION amyotrophic lateral sclerosis
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ECOC多类分类中基分类器non-competence问题研究 被引量:1
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作者 雷蕾 王晓丹 +1 位作者 权文 罗玺 《系统工程与电子技术》 EI CSCD 北大核心 2017年第12期2637-2645,共9页
在纠错输出编码(error-correcting output code,ECOC)多类分类中,当待识别样本的真实类别不属于对应二类子类划分时,训练得到的基分类器将不具备对此类样本进行分类的能力,此时的基分类器在解码融合时面临着non-competence问题。如何衡... 在纠错输出编码(error-correcting output code,ECOC)多类分类中,当待识别样本的真实类别不属于对应二类子类划分时,训练得到的基分类器将不具备对此类样本进行分类的能力,此时的基分类器在解码融合时面临着non-competence问题。如何衡量基分类器是否具备对样本的分类能力,以及如果不具备,如何减少此种情况下对分类效果的影响是基于ECOC多类分类面临的新问题。针对解码框架中non-competent基分类器的分类融合问题,提出一种基于基分类器对样本是否具有分类能力的加权解码方法。该方法利用支持向量数据描述衡量待识别样本与各划分子类之间的距离,同时利用加权解码,通过对基分类器权重的学习,进而增强对类别拥有分类能力的基分类器的影响,减少不具备分类能力的基分类器产生的误差。基于UCI数据集的实验表明所提方法的有效性和实用性。 展开更多
关键词 多类分类 纠错输出编码 分类能力 支持向量数据描述
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物联网系统助力智能雾化室精益化管理 被引量:1
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作者 徐锡凤 权雯 项红霞 《中国数字医学》 2019年第7期115-117,共3页
目的:依托物联网技术构建智能化雾化治疗室,为患儿提供优质便捷的医疗服务。方法:随机挑选120名在智能雾化室治疗的患儿为观察组,120名在普通雾化治疗室的患儿为对照组,两者进行依从性、疗效及满意度的调查。结果:观察组患儿依从性、疗... 目的:依托物联网技术构建智能化雾化治疗室,为患儿提供优质便捷的医疗服务。方法:随机挑选120名在智能雾化室治疗的患儿为观察组,120名在普通雾化治疗室的患儿为对照组,两者进行依从性、疗效及满意度的调查。结果:观察组患儿依从性、疗效以及满意度均明显高于对照组,两者相比有统计学差异(P<0.05)。结论:智能雾化室的建设大大改善了患儿的依从性,从而提高了治疗效果和患者满意度。 展开更多
关键词 物联网 智能雾化室 依从性 疗效 满意度
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miR-221通过调节PTEN影响肺癌细胞对吉非替尼的耐药性 被引量:8
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作者 郑礼平 陈艺丹 +3 位作者 张楠 全文 梁翠微 龚五星 《中国病理生理杂志》 CAS CSCD 北大核心 2019年第3期454-458,共5页
目的:探讨微小RNA-221(miR-221)在人肺癌细胞对吉非替尼耐药中的作用及其相关机制。方法:RT-qPCR检测人肺腺癌吉非替尼敏感细胞PC9和吉非替尼耐药细胞PC9/GR中miR-221的表达;通过脂质体试剂Lipofectamine 2000把miR-221 inhibitor转染... 目的:探讨微小RNA-221(miR-221)在人肺癌细胞对吉非替尼耐药中的作用及其相关机制。方法:RT-qPCR检测人肺腺癌吉非替尼敏感细胞PC9和吉非替尼耐药细胞PC9/GR中miR-221的表达;通过脂质体试剂Lipofectamine 2000把miR-221 inhibitor转染入肺癌PC9/GR细胞内,CCK-8法检测细胞对吉非替尼敏感度的变化,Western blot检测第10号染色体缺失的磷酸酶及张力蛋白同源物(PTEN)的蛋白表达。构建含PTEN 3’-UTR的萤光素酶报告载体,验证miR-221对PTEN的靶向调控作用。结果:PC9/GR细胞的miR-221表达水平明显高于PC9细胞(P<0.05)。PC9/GR细胞中PTEN表达水平低于PC9细胞(P<0.05)。转染miR-221 inhibitor后,吉非替尼对PC9/GR细胞的IC_(50)明显降低,PTEN的蛋白表达增加(P<0.05)。萤光素酶活性检测实验显示抑制miR-221表达能增强PTEN的萤光素酶活性(P<0.05)。结论:miR-221可能通过抑制PTEN的表达,增强肺癌细胞对吉非替尼的耐药性。 展开更多
关键词 肺癌 微小RNA-221 PTEN蛋白 吉非替尼 耐药性
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Impact of travel speed on the microstructure and mechanical properties of adjustable-gap bobbin-tool friction stir welded Al–Mg joints 被引量:3
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作者 Dong Wu wen-ya Li +4 位作者 Yan-jun Gao Jun Yang quan wen Nektarios Vidakis Achillefs Vairis 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第4期710-717,共8页
The butt welds of 4-mm thick 5A06 aluminum alloy plates were produced by adjustable-gap bobbin-tool friction stir travel with travel speeds of 200, 300, and 400 mm/min in this study.The microstructure was studied usin... The butt welds of 4-mm thick 5A06 aluminum alloy plates were produced by adjustable-gap bobbin-tool friction stir travel with travel speeds of 200, 300, and 400 mm/min in this study.The microstructure was studied using optical microscopy and electron backscatter diffraction(EBSD).Tensile tests and microhardness measurements were performed to identify the effect of the travel speed on the joint mechanical properties.Sound joints were obtained at 200 mm/min while voids were present at different positions of the joints as the travel speed increased.The EBSD results show that the grain size, high angle grain boundaries, and density of geometrically necessary dislocations in different regions of the joint vary depending on the recovery and recrystallization behavior.Specific attention was given to the relationship between the local microstructure and mechanical properties.Microhardness measurements show that the average hardness of the stir zone(SZ) was greater than that of the base material, which was only affected slightly by the travel speed.The tensile strength of the joint decreased with increasing travel speed and the maximal strength efficiency reached 99%. 展开更多
关键词 friction stir welding bobbin-tool aluminum alloy microstructure mechanical properties adjustable-gap
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A comprehensive review of miniatured wind energy harvesters 被引量:4
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作者 quan wen Xianming He +2 位作者 Zhuang Lu Reinhard Streiter Thomas Otto 《Nano Materials Science》 CAS CSCD 2021年第2期170-185,共16页
Following the current rapid development of the Internet of Things(IoT)and wireless condition monitoring systems,energy harvesters which use ambient energy have become a key part of achieving an energy-autonomous syste... Following the current rapid development of the Internet of Things(IoT)and wireless condition monitoring systems,energy harvesters which use ambient energy have become a key part of achieving an energy-autonomous system.Miniature wind energy harvesters have attracted widespread attention because of their great potential of power density as well as the rich availability of wind energy in many possible areas of application.This article provides readers with a glimpse into the state-of-the-art of miniature wind energy harvesters.The crucial factors for them to achieve high working efficiency under lower operational wind speed excitation are analyzed.Various potential energy coupling mechanisms are discussed in detail.Design approaches for broadening operational wind-speed-range given a variety of energy coupling mechanisms are also presented,as observed in the literature.Performance enhancement mechanisms including hydrodynamic configuration optimization,and non-linear vibration pick-up structure are reviewed.Conclusions are drawn and the outlook for each coupling mechanisms is presented. 展开更多
关键词 Energy harvester Wind energy Miniature wind-induced vibration energy harvester Energy coupling mechanism Performance enhancement mechanisms
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Impact of cap-assisted colonoscopy during transendoscopic enteral tubing:A randomized controlled trial 被引量:2
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作者 quan wen Kang-Jian Liu +11 位作者 Bo-Ta Cui Pan Li Xia Wu Min Zhong Lu Wei Hua Tu Yu Yuan Da Lin wen-Hung Hsu Deng-Chyang Wu Hong Yin Fa-Ming Zhang 《World Journal of Gastroenterology》 SCIE CAS 2020年第39期6098-6110,共13页
BACKGROUND Colonic transendoscopic enteral tubing(TET)requires double cecal intubation,raising a common concern of how to save cecal intubation time and make the tube stable.We hypothesized that cap-assisted colonosco... BACKGROUND Colonic transendoscopic enteral tubing(TET)requires double cecal intubation,raising a common concern of how to save cecal intubation time and make the tube stable.We hypothesized that cap-assisted colonoscopy(CC)might reduce the second cecal intubation time and bring potential benefits during the TET procedure.AIM To investigate if CC can decrease the second cecal intubation time compared with regular colonoscopy(RC).METHODS This prospective multicenter,randomized controlled trial was performed at four centers.Subjects≥7 years needing colonic TET were recruited from August 2018 to January 2020.All subjects were randomly assigned to two groups.The primary outcome was the second cecal intubation time.Secondary outcomes included success rate,insertion pain score,single clip fixation time,purpose and retention time of TET tube,length of TET tube inserted into the colon,and all procedurerelated(serious)adverse events.RESULTS A total of 331 subjects were randomized to the RC(n=165)or CC(n=166)group.The median time of the second cecal intubation was significantly shorter for CC than RC(2.2 min vs 2.8 min,P<0.001).In patients with constipation,the median time of second cecal intubation in the CC group(n=50)was shorter than that in the RC group(n=43)(2.6 min vs 3.8 min,P=0.004).However,no difference was observed in the CC(n=42)and RC(n=46)groups of ulcerative colitis patients(2.0 min vs 2.5 min,P=0.152).The insertion pain score during the procedure in CC(n=14)was lower than that in RC(n=19)in unsedated colonoscopy(3.8±1.7 vs 5.4±1.9;P=0.015).Multivariate analysis revealed that only CC(odds ratio[OR]:2.250,95%confidence interval[CI]:1.161-4.360;P=0.016)was an independent factor affecting the second cecal intubation time in difficult colonoscopy.CC did not affect the colonic TET tube’s retention time and length of the tube inserted into the colon.Moreover,multivariate analysis found that only endoscopic clip number(OR:2.201,95%CI:1.541-3.143;P<0.001)was an independent factor affecting the retention time.Multiple regression analysis showed that height(OR:1.144,95%CI:1.027-1.275;P=0.014)was the only independent factor influencing the length of TET tube inserted into the colon in adults.CONCLUSION CC for colonic TET procedure is a safe and less painful technique,which can reduce cecal intubation time. 展开更多
关键词 Transendoscopic enteral tube ENDOSCOPY COLONOSCOPY Fecal microbiota transplant Washed microbiota transplant COLON
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Bladder malacoplakia: A case report 被引量:2
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作者 Hua-Kang Wang Gai Hang +2 位作者 Yu-Yang Wang quan wen Bo Chen 《World Journal of Clinical Cases》 SCIE 2022年第23期8291-8297,共7页
BACKGROUND Bladder malacoplakia is a rare chronic granulomatous disease.The most common site of the malacoplakia is the urinary system.The etiology of bladder malacoplakia is complex,with its clinical misdiagnosis rat... BACKGROUND Bladder malacoplakia is a rare chronic granulomatous disease.The most common site of the malacoplakia is the urinary system.The etiology of bladder malacoplakia is complex,with its clinical misdiagnosis rate is high.Therefore,exposure to more clinical cases is necessary to improve the diagnosis and treatment of this condition.CASE SUMMARY A 65-year-old woman was admitted to our hospital because of dysuria.She presented with dysuria,frequent urination,urgency,pain,and absence of hematuria and pyuria.After the examination,bladder tumor electrocision was performed under combined intravenous and inhalation anesthesia on September 6,2021.During the operation,electrotomy and electrocoagulation were performed.The operation was then followed by anti-infection treatment,and the patient recovered well.The postoperative pathology was diagnosed as bladder malacoplakia by light and electron microscopic analyses.On a follow-up after 4 mo,no significant difference between electrotomy and electrocoagulation was found,with both achieving a curative effect.CONCLUSION Diagnosing bladder malacoplakia depends on histopathological examination.Antibiotic treatment with bladder tumor resection or electrocoagulation provides better therapeutic effect. 展开更多
关键词 Bladder malacoplakia Michaelis-Gutman bodies Transurethral resection PATHOLOGY Case report
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局部晚期肺癌同步放化疗后表皮生长因子受体酪氨酸激酶抑制剂维持治疗的临床研究 被引量:2
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作者 郑礼平 全文 +3 位作者 谢云 彭东旭 梁翠微 龚五星 《实用医学杂志》 CAS 北大核心 2018年第21期3573-3576,共4页
目的探讨表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)在局部晚期非小细胞肺癌(NSCLC)同步放化疗后维持治疗中的价值。方法晚期NSCLC患者同步放化疗后,最终病情无进展的有88例,将其随机分为TKI药物组(吉非替尼250 mg,每日1次或者厄洛替... 目的探讨表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)在局部晚期非小细胞肺癌(NSCLC)同步放化疗后维持治疗中的价值。方法晚期NSCLC患者同步放化疗后,最终病情无进展的有88例,将其随机分为TKI药物组(吉非替尼250 mg,每日1次或者厄洛替尼150 mg,每日1次),或安慰剂组。维持治疗时间为1年,但如果维持治疗期间出现病情进展或严重不良反应则停药。结果 TKI药物组、安慰剂组的疾病控制率分别是81.8%、61.4%(P=0.033)。两组的中位疾病进展时间分别为13.6、10.8个月,差异有统计学意义(P=0.001)。TKI药物组中位生存时间34.5个月较安慰剂组30.3个月明显延长(P=0.029)。TKI药物的不良反应有皮疹、腹泻、疲劳、肝功能损害等,未出现治疗相关的死亡。结论 TKI药物用于局部晚期NSCLC同步放化疗后的维持治疗,可以提高疾病控制率,延长患者生存期,并且不良反应能耐受。 展开更多
关键词 局部晚期 非小细胞肺癌 表皮生长因子受体酪氨酸激酶抑制剂 维持治疗
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Review of Numerical Simulation of TGO Growth in Thermal Barrier Coatings 被引量:1
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作者 quan wen Fulei Jing +2 位作者 Changxian Zhang Shibai Tang Junjie Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第8期361-391,共31页
Thermally grown oxide(TGO)is a critical factor for the service life of thermal barrier coatings(TBC).Numerical simulations of the growth process of TGO have become an effective means of comprehensively understanding t... Thermally grown oxide(TGO)is a critical factor for the service life of thermal barrier coatings(TBC).Numerical simulations of the growth process of TGO have become an effective means of comprehensively understanding the progressive damage of the TBC system.At present,technologies of numerical simulation to TGO growth include two categories:coupled chemical-mechanical methods and mechanical equivalent methods.The former is based on the diffusion analysis of oxidizing elements,which can describe the influence of bond coat(BC)consumption and phase transformation in the growth process of TGO on the mechanical behavior of each layer of TBC,and has high accuracy for the thickness evolution of TGO,but they cannot describe the lateral growth of TGO and the rumpling phenomenon induced.The latter focuses on describing the final stress and strain state after the growth of a specific TGO rather than the complete growth processes of TGO.Based on the measured TGO thickness growth curve,simulations of thickening and lateral growth can be achieved by directly applying anisotropic volumetric strain to oxidized elements and switching elements properties from the BC to the TGO. 展开更多
关键词 Thermal grown oxide(TGO) numerical simulation thermal barriers coatings(TBC) finite element method lateral growth
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4-碘-2-甲基吡啶的合成工艺研究
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作者 权文 李飞 赵春深 《化学研究与应用》 CAS CSCD 北大核心 2018年第5期851-854,共4页
4-碘-2-甲基吡啶是一个重要的医药化工中间体。本文以2-甲基-4-硝基吡啶-N-氧化物为起始原料,经还原和Sandmeyer反应得到目标化合物,总收率为73.5%。目标化合物的结构经~1H NMR、^(13)C NMR和MS确证。经优化后的工艺具有原料廉价易得、... 4-碘-2-甲基吡啶是一个重要的医药化工中间体。本文以2-甲基-4-硝基吡啶-N-氧化物为起始原料,经还原和Sandmeyer反应得到目标化合物,总收率为73.5%。目标化合物的结构经~1H NMR、^(13)C NMR和MS确证。经优化后的工艺具有原料廉价易得、操作简便、制备周期短且收率较高等优点,适合工业化生产。 展开更多
关键词 4-碘-2-甲基吡啶 2-甲基4-硝基吡啶-N-氧化物 合成
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Genetic Analysis of a Strong Convective Weather Process in Guannan County
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作者 quan wen Yongjun Zhang +1 位作者 Xiangbang wen Zhaotang Shang 《Meteorological and Environmental Research》 CAS 2013年第1期18-20,25,共4页
To provide references for the forecast of strong convective weather process by county-level stations, through synoptic analysis, diagnostic analysis of physical quantities, analysis of satellite cloud pictures and new... To provide references for the forecast of strong convective weather process by county-level stations, through synoptic analysis, diagnostic analysis of physical quantities, analysis of satellite cloud pictures and new generation of weather radar data, the main reasons for the formation of strong convective weather process in Guannan County on May 16, 2012 was analysed based on the weather situation and physical quantities. The results show that this strong convective weather process occurred under conditions of inversion layer, upper dry and low-level wet climate, high- level convergence and low-level divergence, and unstable stratification, and surface cold front was the major factor triggering this strong convection. Besides, radar echo played an important role in the short-term impending forecast during the development of the weather. The occurrence of a strong convective weather is related to cold air activity, so we should strengthen the monitoring of cold air activity, so as to improve our waming lev- el and service capability to forecast strong convective weather. 展开更多
关键词 Strong convection CAUSE Weather situation Physical quantities China
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Research progress of male sexual dysfunction following stroke
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作者 quan wen Gai Hang +2 位作者 Hua-Kang Wang Ling-Xue Bao Bo Chen 《Psychosomatic Medicine Research》 2020年第4期117-122,共6页
Stroke is a major disabling and fatal disease worldwide.There are many studies on neurological deficits and cognitive impairment after stroke,but there are few studies on sexual dysfunction,which is an important part ... Stroke is a major disabling and fatal disease worldwide.There are many studies on neurological deficits and cognitive impairment after stroke,but there are few studies on sexual dysfunction,which is an important part of patients'quality of life.Studies have shown that male sexual dysfunction following stroke is very common,such as loss of libido,erectile dysfunction and ejaculatory weakness.Among them,young male stroke patients have particularly high requirements for quality of life and are ashamed to speak when they have secondary dysfunction.Related knowledge and degree of attention of medical staff are also relatively less.The location and area of stroke and the occurrence and development process of the disease may affect the sexual function of patients.Its etiology roughly includes both organic and functional aspects.Further study of post-stroke sexual dysfunction and strengthening the diagnosis and treatment of sexual dysfunction in stroke patients should be included in the category of stroke rehabilitation. 展开更多
关键词 STROKE Quality of life Sexual dysfunction
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Thermal Analysis of an Antenna
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作者 Kuiyuan Shen Guangyu Wang quan wen 《Journal of Applied Mathematics and Physics》 2022年第8期2574-2580,共7页
In order to study the internal temperature changes and heat transfer phenomena of a model during external warming, a heat transfer simulation was conducted. The thermal analysis of the model was simulated by using ANS... In order to study the internal temperature changes and heat transfer phenomena of a model during external warming, a heat transfer simulation was conducted. The thermal analysis of the model was simulated by using ANSYS/LSDYNA software, and the heat and heat transfer phenomena of the warhead in the actual process were simulated by setting the temperature conditions on the surface of the model, and the model boundary and internal temperature changes were obtained from the simulation experiments, and relevant conclusions were drawn. 展开更多
关键词 Thermal Analysis Simulation Heat Transfer
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