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基于模糊故障树的某高炮无线电引信安全评估

兵器装备工程学报 2024年第2期45卷 76-82页

作者：贺玮李波麻旭东中北大学机电工程学院太原030051 中国人民解放军61767部队

针对引信系统长期贮藏造成的性能下降、作用过程环境复杂、内部结构失效等情况,和传统的Bell故障树分析方法受限于二元的故障描述状态以及与或关系的限制,提出一种基于模糊故障树的引信安全性评估方法。对模糊故障树进行顶事件概率计算... 详细信息

针对引信系统长期贮藏造成的性能下降、作用过程环境复杂、内部结构失效等情况,和传统的Bell故障树分析方法受限于二元的故障描述状态以及与或关系的限制,提出一种基于模糊故障树的引信安全性评估方法。对模糊故障树进行顶事件概率计算和底事件重要度分析,体现出引信系统故障机制和事件联系的模糊性和事件发生的时序性。利用该评估方法对某小口径高炮无线电引信在预定的解除保险和解除隔离流程开始前引信作用故障树进行实例分析,并与传统Bell故障树分析结果进行对比。结果表明:模糊故障树计算所得的失效率为2.1×10-9,Bell故障树计算所得的顶事件概率值为1.2×10-9,两者为同一数量级,且模糊故障树的重要度分析更加快速和高效,能更加科学地进行引信安全性评估和故障树诊断。

关键词：引信模糊故障树 Bell故障树安全性评估重要度分析

Research on Deformation Mode of the Longmenshan-Longriba Region Using GPS and Leveling Data

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International Journal of Geosciences 2023年第7期14卷 619-634页

作者： xudong li Wei li Jiangtao Qiu Bing Feng Xiang liu The Second Monitoring and Application Center China Earthquake Administration Xi’an China Institute of Geology China Earthquake Administration Beijing China

The Longmenshan-Longriba region is located on the eastern edge of the Tibetan Plateau, and is an ideal place to study the eastward extrusion and uplift mechanism of the plateau. Previous studies on this area mainly focused on tectonic activity and seismic hazard, with few studies giving its overall deformation characteristics and dynamic mechanism. This paper uses the latest dense GPS data, combined with precise Leveling data to analyze the kinematic characteristics and deformation mode of the Longmenshan fault zone (LMSF) and the Longriba fault zone (LRBF). The results show that both the Longmenshan fault zone and the Longriba fault zone have certain right-lateral strike-slip and thrusting, indicating that they play an important role in adjusting strain distribution and absorbing tectonic deformation;The strain-rate field on the Longriba fault zone is broadly distributed, suggesting that the deformation field is at least partially coupled;while the strain-rate field on the Longmenshan fault zone presents a non-uniform distribution, indicating different dynamic sources acting on segments. The high strain rate areas revealed in this study points us to the high-risk area for future earthquakes. The present-day vertical motion velocity field in the region obtained from Leveling and GPS data shows a mismatch between the regional deformation field and active tectonics, which can be explained by the incomplete coupling of deformation between the lower and upper crust.

关键词： Longmenshan Fault Zone Longriba Fault Zone GPS Strain Leveling

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耳甲腔毛母细胞瘤1例并文献复习

临床耳鼻咽喉头颈外科杂志 2024年第5期38卷 448-452页

作者：李雪雪卫旭东李淑娟王倩茹潘鑫兰州大学第一临床医学院兰州730000 甘肃省人民医院耳鼻咽喉头颈外科甘肃中医药大学

毛母细胞瘤(trichoblastoma,TB)是一种罕见的毛发生殖细胞皮肤附件肿瘤,罕见的皮肤滤泡肿瘤,分化于毛胚上皮,常被视为良性皮肤肿瘤,但局限性差且具有局部浸润性生长模式。TB好发于头部和颈部区域,尤其是面部,临床表现为生长缓慢、边界... 详细信息

毛母细胞瘤(trichoblastoma,TB)是一种罕见的毛发生殖细胞皮肤附件肿瘤,罕见的皮肤滤泡肿瘤,分化于毛胚上皮,常被视为良性皮肤肿瘤,但局限性差且具有局部浸润性生长模式。TB好发于头部和颈部区域,尤其是面部,临床表现为生长缓慢、边界清晰及隆起的结节。TB常规以手术治疗为主,由于目前缺乏普遍接受的治疗指南或方案,术后复发率高,为临床治愈增加了一定的难度。本研究报道1例65岁女性患者,发现右侧外耳道口及耳甲腔肿物并反复破溃流脓,最初误诊为外耳道炎,以常规抗感染治疗,症状未缓解并逐渐加重后来我院就诊。该病例所展现的病症极为罕见,因此,及时且准确的诊断与治疗对此类疫病的诊疗和预后至关重要。

关键词：毛母细胞瘤毛源性肿瘤耳甲腔良性肿瘤诊断治疗

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304不锈钢激光微抛光的数值模拟与分析

光电子．激光 2024年第1期35卷 91-100页

作者：李道齐王涛黄旭东河北工业大学机械工程学院天津300401

为了将激光抛光金属表面的过程可视化,本文建立了脉冲激光抛光304不锈钢的二维瞬态数值模型,模拟了脉冲激光作用下304不锈钢表面形貌的演变过程,揭示了抛光过程中传热、熔化和凝固等物理过程的演化机制。模拟结果表明,与连续激光抛光相... 详细信息

为了将激光抛光金属表面的过程可视化,本文建立了脉冲激光抛光304不锈钢的二维瞬态数值模型,模拟了脉冲激光作用下304不锈钢表面形貌的演变过程,揭示了抛光过程中传热、熔化和凝固等物理过程的演化机制。模拟结果表明,与连续激光抛光相比,脉冲激光会使抛光表面产生细小的波纹,但是整体上空间曲率会减小,能够起到一定的抛光效果。在表面形貌的演化过程中,表面起伏较大的区域,由毛细力主导熔池内熔体的流动,其主要作用是消除具有大区率的表面形貌;表面曲率较小的区域,则由热毛细力占据主导地位,其主要作用是促使熔融金属在熔池中重新分布,进一步降低表面的粗糙度。为了验证仿真模型的正确性,通过与实验结果的比较,发现模型熔池深度与实验结果相符合,具有较高的模拟精度。

关键词：激光抛光高斯热源数值模拟表面形貌

Comparison of the osteogenic capability of rat bone mesenchymal stem cells on collagen,collagen/hydroxyapatite,hydroxyapatite and biphasic calcium phosphate

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Regenerative Biomaterials 2018年第2期5卷 93-103页

作者： Xiaoyu Sun Wen Su Xiaomin Ma Huaiying Zhang Zhe Sun xudong li National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064P.R.China

Collagen(COL),collagen/hydroxyapatite(COL/HA),HA and biphasic calcium phosphate were prepared as representative bone grafting materials with composition analogous to bone,and their structural characteristics were analyzed.The rat bone mesenchymal stem cells(BMSCs)were further seeded onto four groups of materials,and BMSCs grown in basic medium and standard osteogenic medium were set as controls of a reference model to show the basic and osteogenic behavior of cells without the intervention of materials.Cellular behaviors were characterized,including proliferation,spreading morphology and expression of osteogenesis factors.The rat BMSCs proliferated properly with time on four groups of materials as well on two groups of controls,and typical cuboidal,polygonal and extremely-elongated morphologies of cells were observed.According to the real-time polymerase chain reaction data,a higher osteogenic gene expression level was dependent upon the growing morphology but not the proliferation rate of cells,and the osteogenic differentiation capacity of cells onto four groups of materials varied in specific genes.In general,BMSCs exhibited the highest osteogenic capacity onto COL/HA,but the poorest onto HA.The growing behaviors of cells on materials were further discussed in comparison with the cases of OC and BC of the reference model.The present attempt to comparatively analyze cell experimental data with a reference model is expected to be useful for revealing the difference in the osteogenic capability of MSCs onto materials or even the bioactivity of materials.

关键词： osteogenic differentiation spreading morphology mineralization of collagen bioceramics

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适用于约束环境的轻量级目标检测模型

计算机工程与应用 2024年第6期60卷 274-281页

作者：曲海成袁旭东李佳琦辽宁工程技术大学软件学院辽宁葫芦岛125105

为了进一步降低目标检测模型YOLOX-Tiny的大小并提高检测精度,以便于更好地适用于计算资源和存储空间有限的环境,在特征金字塔的结构、解耦头的结构和损失函数上对其进行改进,形成一种更高性能的轻量级目标检测模型lite-YOLOX。为进一... 详细信息

为了进一步降低目标检测模型YOLOX-Tiny的大小并提高检测精度,以便于更好地适用于计算资源和存储空间有限的环境,在特征金字塔的结构、解耦头的结构和损失函数上对其进行改进,形成一种更高性能的轻量级目标检测模型lite-YOLOX。为进一步压缩原有模型体积,重新设计特征金字塔和解耦头的结构,使模型的Neck和Head部分更轻量化;为提升模型的检测精度,在原有IoU损失函数的基础上进行优化,设计并提出EIoU损失函数,改进后的损失函数对真实框和预测框的位置更加敏感;选取PASCAL VOC和安全帽检测数据集对改进模型进行验证。实验结果表明:lite-YOLOX与YOLOX-Tiny相比,参数量减少40%,计算量下降37.5%,mAP50提升3.2和3.1个百分点。在NVIDIA Jetson Xavier NX上,每秒传输帧数(FPS)从51增加到59,实时性有了明显的提升。

关键词：目标检测轻量化特征融合损失函数

Plasma levels of luteinizing hormone and prolactin in relation to double brooding in Great Tit(Parus major)

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Avian Research 2022年第1期13卷 102-107页

作者： xudong li Wenyu Xu Jiangping Yu Wutong Zhang Haitao Wang Jilin Engineering Laboratory for Avian Ecology and Conservation Genetics School of Life SciencesNortheast Normal UniversityChangchun130024China Jilin Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchun130024China

The reproductive behaviors of birds are mainly controlled by the hypothalamus-pituitary-gonad axis.Many studies have shown that reproductive hormones are tightly linked to the breeding sub-stages.However,only a few studies have examined the temporal trend of hormone levels among different reproductive stages in multiple brooded species.We investigated the changes in plasma luteinizing hormone(LH)and prolactin(PRL)concentrations during different reproductive stages of the facultative double-brooded Great Tit(Parus major).We found that the concentrations of LH and PRL in females were significantly higher than those in males.Females had significantly higher LH and lower PRL concentrations in the pre-breeding period than in the first/second brooding periods,and there were no significant changes between the first and second brooding periods.The concentrations of LH and PRL in males had no significant difference between the pre-breeding period and the first brooding periods,while LH and PRL concentrations in the second brooding period were significantly higher than those in the first brooding period.We conclude that there are sex-based differences between LH and PRL at different stages of reproduction.The changes in LH and PRL in both males and females should be related to their physiological functions.Especially for males,individuals with higher levels of LH and PRL are more likely to maintain second clutches.

关键词： Birds Great Tit Luteinizing hormone Prolactin Seasonal breeding

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阮大成古体诗用韵研究

语言与文化研究

语言与文化研究 2024年第4期32卷 38-43页

作者：李绪东云南师范大学昆明650500

本文穷尽式系联、分析了阮大铖所创作的166古体诗271个韵段,发现共分为19个韵部,其中:阴声韵7部、阳声韵7部、入声韵5部。阮大铖在用韵时依照明末通语入韵,但从通押情况来看,反映出明末怀宁方音的某些特点:支微部与鱼模部通押、支微部... 详细信息

本文穷尽式系联、分析了阮大铖所创作的166古体诗271个韵段,发现共分为19个韵部,其中:阴声韵7部、阳声韵7部、入声韵5部。阮大铖在用韵时依照明末通语入韵,但从通押情况来看,反映出明末怀宁方音的某些特点:支微部与鱼模部通押、支微部与灰咍部通押、-m、-n、-?通押、阴入通押、“浊上变去”和入声韵-p、-t、-k的混押等。

关键词：阮大铖古体诗韵特韵研究语音演变

电碳耦合对煤电机组现货市场结算电价影响分析模型

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中国电力 2024年第5期57卷 113-125页

作者：李祥光谭青博李帆琪李旭东谭忠富华北电力大学经济与管理学院北京102206 蒙古CITI大学乌兰巴托999097-15141 延安大学经济与管理学院陕西延安716000

煤电行业二氧化碳排放量占比最多,首先被纳入了全国性碳市场,而碳排放成本又对煤电现货市场结算电价造成一定程度的影响。基于此,构建了现货市场下不考虑碳排放成本的煤电机组竞价调度模型,并进行了模拟分析;继而构建了考虑碳排放成本... 详细信息

煤电行业二氧化碳排放量占比最多,首先被纳入了全国性碳市场,而碳排放成本又对煤电现货市场结算电价造成一定程度的影响。基于此,构建了现货市场下不考虑碳排放成本的煤电机组竞价调度模型,并进行了模拟分析;继而构建了考虑碳排放成本的煤电机组竞价模型;再以广东省为例,模拟了煤电机组在“有无风光出力”“不同碳市场”情景下煤电机组现货市场报价及出清情况的变化。结果显示,随着碳市场的逐步完善,碳价和配额总量进一步收紧,煤电机组报价逐渐升高,现货市场结算电价也随之提高,夏季有风有光情景下轻度、中度、重度碳市场的平均出清电价分别为0.1607元/(kW·h)、0.1863元/(kW·h)、0.2461元/(kW·h),较未引入碳市场时分别增加了0.18%、16.14%、53.41%。

关键词：碳市场现货市场结算电价碳排放成本电碳耦合