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Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China mathematics 2024年第1期67卷 211-236页

作者： Qi Lü Bowen ma School of mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

硫代乙内酰脲衍生物Ru59063的公斤级合成

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精细化工 2023年第12期40卷 2781-2784页

作者：赵娅敏李泽坤魏立梁马瑜浩刘荣西北民族大学化工学院甘肃兰州730000 甘肃省高校环境友好复合材料及生物质利用省级重点实验室甘肃兰州730000 甘肃省化工研究院有限责任公司甘肃兰州730000 甘肃省精细化工重点实验室甘肃兰州730020

对Ru59063的合成进行了改进。首先,4-氨基-2-(三氟甲基)苯甲腈(Ⅲ)与硫光气反应,制备了4-异硫氰基-2-(三氟甲基)苯腈(Ⅳ);然后,中间体Ⅳ与2-氨基异丁酸甲酯盐酸盐进行[3+2]环加成反应,合成了4-(2-硫代-4,4-二甲基-5-氧代咪唑烷-1-基)-2... 详细信息

对Ru59063的合成进行了改进。首先,4-氨基-2-(三氟甲基)苯甲腈(Ⅲ)与硫光气反应,制备了4-异硫氰基-2-(三氟甲基)苯腈(Ⅳ);然后,中间体Ⅳ与2-氨基异丁酸甲酯盐酸盐进行[3+2]环加成反应,合成了4-(2-硫代-4,4-二甲基-5-氧代咪唑烷-1-基)-2-三氟甲基苯腈(Ⅶ);化合物Ⅶ再与叔丁基-(4-氯丁氧基)-二甲基硅烷通过乌尔曼C—N偶联反应,得到了4-{3-[4-(叔丁基二甲基硅基)-羟基丁基]-4,4-二甲基-5-氧代-2-硫代咪唑烷-1-基}-2-(三氟甲基)苯甲腈(Ⅷ);最后,中间体Ⅷ进行羟基脱保护得到Ru59063,4步反应总收率为61.6%,HPLC纯度为98.2%。与传统方法相比,该法收率提高了4.7倍,并且未使用氰化物,可以更方便、更安全地制备了Ru59063。对2 kg 4-氨基-2-(三氟甲基)苯甲腈进行了放大实验,总收率可达到60.7%。

关键词： Ru59063 硫光气硫代乙内酰脲 [3+2]环加成乌尔曼C—N偶联反应精细化工中间体

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Nuance of inward rectifying potassium(Kir)channel dysfunctions in neurodegenerative diseases

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Neural Regeneration Research 2024年第6期19卷 1195-1196页

作者： Benjamin Garland Linlin ma Griffith Institute for Drug Discovery&School of Environment and Science Griffith UniversityNathanBrisbaneQLDAustralia

Neurodegenerative disorders are highly prevalent and diverse in *** manifestation largely depends on the cell types involved,with aberrant inflammatory episodes progressively inducing a constellation of phenotypes that are classified into specific diseases based on their neuropathological *** two most prevalent neurodegenerative diseases worldwide,Alzheimer’s disease(AD)and Parkinson’s disease(PD),for example,share notable similarities,yet they differ in terms of the specific cell types lost within the central nervous system(CNS).The significant and progressive loss of cortical and certain subcortical neurons in various regions is a major defining trait of *** contrast,the specific loss of dopaminergic neurons(DA)within the substantial nigra pars compacta(SNpc)is sufficient to cause motor symptoms associated with *** devastating condition arising from neurodegeneration within the CNS,amyotrophic lateral sclerosis(ALS),results in the progressive death of upper and lower motor *** degeneration originates in oligodendrocytes,whose defective myelination abilities lead to the denervation of the anterior horn,aggravating motor neuron death.

关键词： diseases degenerative degeneration

Take Every Step Firmly with Sharp Eyes

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Chinese Journal of Chemistry 2024年第10期42卷 1065-1066页

作者： Shengming ma Chinese Journal of Chemistry

Chinese Journal of Chemistry(CJC)is committed to becoming a prominent international journal for chemistry and the related *** are working very hard towards this *** offers a diverse range of manuscript types,including... 详细信息

关键词： journal becoming diverse

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一种粗铣刀周齿分屑槽的数控磨削工艺算法

机械科学与技术 2023年第9期42卷 1430-1435页

作者：李海宾王成兵马玉豪江磊西南交通大学机械工程学院先进设计与制造技术研究所成都610031

针对粗铣刀分屑槽形状的磨削工艺,对粗铣刀周齿分屑槽结构参数进行了定义,建立了加工坐标系及切深引导曲线方程;借助运动学理论,提出了砂轮磨削姿态和砂轮磨削轨迹的计算方法;在VC++环境开发了一套算法模块,并对其进行了仿真验证及与Num... 详细信息

针对粗铣刀分屑槽形状的磨削工艺,对粗铣刀周齿分屑槽结构参数进行了定义,建立了加工坐标系及切深引导曲线方程;借助运动学理论,提出了砂轮磨削姿态和砂轮磨削轨迹的计算方法;在VC++环境开发了一套算法模块,并对其进行了仿真验证及与Numroto磨削软件的仿真结果对比。结果表明,该轨迹算法能够较好的实现预期效果,具有较好的刀具结构扩展性和加工精度。

关键词：粗铣刀周齿分屑槽磨削轨迹算法

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经鼻内镜复杂脑脊液鼻漏修补术三例

中华耳鼻咽喉头颈外科杂志 2017年第1期52卷 62-64页

作者：文开学马培如张宇皓赵军山西大医院耳鼻咽喉头颈外科太原030032

经鼻内镜脑脊液鼻漏修补术因其视野清晰、成功率高、并发症少而逐渐成为脑脊液鼻漏修补的首选方法，随着内镜技术的日趋成熟，鼻内镜下脑脊液鼻漏修补术的成功率越来越高，但一些复杂的脑脊液鼻漏，如缺损较大、复发、非单一漏口、伴有... 详细信息

经鼻内镜脑脊液鼻漏修补术因其视野清晰、成功率高、并发症少而逐渐成为脑脊液鼻漏修补的首选方法，随着内镜技术的日趋成熟，鼻内镜下脑脊液鼻漏修补术的成功率越来越高，但一些复杂的脑脊液鼻漏，如缺损较大、复发、非单一漏口、伴有其他畸形或并发症的手术仍被鼻科医生视为挑战。现将我科自2007年7月至2015年6月收治的3例经鼻内镜修补的复杂脑脊液鼻漏患者的资料汇报如下。

关键词：脑脊液鼻漏修补术经鼻内镜视野清晰内镜技术鼻内镜下并发症功率

Development of a novel signal restoration algorithm to eliminate the distorted components in space charge measurement excited by femtosecond laser irradiation

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High Voltage 2024年第3期9卷 659-673页

作者： Tianrun Qi Hanwen Ren Haoyu Gao Qingmin Li Yidan ma Yiqun ma Tao Xiao State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina

For the space charge measurement method with optical excitation for electrical insulation,the distortion of the excitation laser on the measurement signal and the accumulation of space charge have not been discussed *** experiment and simulation results show that three types of distorted components introduced by optical excitation can lead to distortion of the upper interface ***,the factors causing distortion of the measured signal and the formation mechanism are analysed.A virtual electrode potential compensation method and a distorted component extraction method are ***,an attenuation restoration and charge conversion correction factor is intro-duced,leading to a novel signal processing algorithm adapted to space charge optical measurement *** with the traditional algorithm,the novel algorithm has an error of less than 1%in the calculation of charge and electric field strength,with an increase in accuracy of 47.7%and 9.81%,*** applying the novel restoration algorithm,the comparison shows that the space charge accumulation does not change significantly under laser irradiation,verifying the reliability of the optical *** given algorithm can provide a theoretical and technical foundation for the realisation of the optical measurement method for space charge.

关键词： charge algorithm excitation

A rigorous real-time acoustic positioning method for ocean bottom seismic exploration

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Satellite Navigation 2024年第1期5卷 168-190页

作者： Jinye ma Shouchuan Fang Jianhu Zhao School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China Institute of marine Science and Technology Wuhan UniversityWuhan430079China Surveying Service Center BGP Inc.CNPCZhuozhou072751HebeiChina

The conventional technique for positioning seafloor geophones in ocean bottom seismic exploration encounters several challenges,including the significant impact of outliers on positioning results,underutilization of high-precision observations,and low efficiency in real-time data *** issues inevitably affect the quality of seismic exploration *** address these challenges and enhance the accuracy of geophone positioning,this paper proposes a rigorous real-time acoustic positioning method for geophones based on sequential adjustment and Baarda's outlier detection *** proposed method comprises three key steps:grouping the original acoustic observations,constructing the intra-group acoustic positioning model,and synthesizing the positioning results across the different *** validity and practicality of this approach are confirmed through a simulation experiment as well as the field experiment conducted in the Bohai Sea,*** results demonstrate that the proposed method effectively eliminates outliers in the original observations and maximizes the utilization of high-quality *** to traditional acoustic positioning methods,it significantly reduces positioning errors from meters to decimeters,and in some cases can achieve centimeter-level *** the sound velocity profile in the operating sea area is measured,the method can attain the posterior standard deviation at the millimeter level and positioning errors within 10 *** the sound velocity profile is unknown,the method can achieve the posterior standard deviation at centimeter-level and positioning errors of approximately 20 cm.

关键词： Ocean bottom seismic exploration Geophone positioning Acoustic positioning method Sequential adjustment Outlier detection

L^(*)—An index for evaluating long range performance of autonomous underwater vehicles(AUVs)

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Friction 2024年第10期12卷 2205-2221页

作者： manfu ZHU Liran ma Jianbin LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Autonomous underwater vehicles(AUVs)have various applications in both military and civilian fields.A wider operation area and more complex tasks require better overall range performance of ***,until recently,there have been few unified criteria for evaluating the range performance of *** the present work,a unified range index,i.e.,L^(*),considering the cruising speed,the sailing distance,and the volume of an AUV,is proposed for the first time,which can overcome the shortcomings of previous criteria using merely one single parameter,and provide a uniform criterion for the overall range performance of various *** constructing the expression of the L^(*)index,the relevant data of 49 AUVs from 12 countries worldwide have been collected,and the characteristics of the L^(*)range index in different countries and different categories were compared and ***,by analyzing the complex factors affecting the range index,methods to enhance the L^(*)range index value,such as efficiency enhancement and drag reduction,have been introduced and *** this condition,the work proposes a unified and scientific criterion for evaluating the range performance of AUVs for the first time,provides valuable theoretical insight for the development of AUVs with higher performance,and then arouses more attention to the application of the cutting-edge superlubricity technology to the field of underwater vehicles,which might greatly help to accelerate the coming of the era of the superlubricitive engineering.

关键词： autonomous underwater vehicles(AUVs) range performance range index superlubricity drag reduction