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警察执法应对暴力对抗行为的防控战术研究

公安研究 2024年第9期 100-106页

作者：李阳肖永伟谢刚广东警官学院警察体育部

警察执法安全关系到警察队伍建设的发展和稳定,更关系到社会的长治久安。近期警察在执法中遇暴力对抗受伤害的情况有上升趋势,特别是持械对抗已对民警的生命构成极大威胁。通过对执法遇暴力对抗行为的现状和案例分析提升安全处置策略,... 详细信息

警察执法安全关系到警察队伍建设的发展和稳定,更关系到社会的长治久安。近期警察在执法中遇暴力对抗受伤害的情况有上升趋势,特别是持械对抗已对民警的生命构成极大威胁。通过对执法遇暴力对抗行为的现状和案例分析提升安全处置策略,从警察执法应对暴力对抗行为的防控战术原则、战术意识深层论述在执法时如何做更加安全;其次从应对遇袭时的常用防控技能去重点研究;最后从执法遇袭防控训练应注意问题进行综合论述,切实提升民警实战素养,维护社会的安全稳定。

关键词：战术研究警察执法处置策略防控战术

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渝西区块龙马溪组强封堵油基钻井液技术研究

西南石油大学学报（自然科学版） 2024年第2期46卷 103-113页

作者：钟成旭李道雄李郑涛谢刚张震中国石油西南油气田公司页岩气研究院四川成都610041 西南石油大学石油与天然气工程学院四川成都610500

渝西区块龙马溪组在水平段钻进过程中因井壁失稳而导致的卡钻、憋顶驱、测井困难等复杂情况频发,研究发现,造成此现象的主要原因是该区块龙马溪组地层微纳米孔、缝发育和钻井液封堵性能不足。因此,在强化现场钻井液封堵性能的基础上优... 详细信息

渝西区块龙马溪组在水平段钻进过程中因井壁失稳而导致的卡钻、憋顶驱、测井困难等复杂情况频发,研究发现,造成此现象的主要原因是该区块龙马溪组地层微纳米孔、缝发育和钻井液封堵性能不足。因此,在强化现场钻井液封堵性能的基础上优选了钻井液主要处理剂,构建了适用于该区块龙马溪组强封堵油基钻井液体系,室内测试结果表明,经过220 nm和450 nm微孔滤膜时未发生滤失,且综合性能均优于普通钻井液。现场应用表明,龙马溪组水平段钻进过程中未出现井壁失稳问题,与同平台采用常规封堵技术的已钻井相比,平均机械钻速提高8.81 m/h,水平段钻井周期缩短2.79 d,铂金靶体钻遇率100%,创渝西区块深层页岩气井5项钻井指标纪录,强封堵油基钻井液技术能满足该区块钻井工程需要。

关键词：井壁稳定油基钻井液强封堵水平井页岩气

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42对棒环形布棒还原炉能量耗散研究

太阳能学报 2024年第9期45卷 268-275页

作者：徐倩彭中李寿琴谢刚侯彦青马文会昆明理工大学复杂有色资源清洁利用国家重点实验室昆明650093 云南通威高纯晶硅有限公司保山678000 四川永祥股份有限公司乐山614000 昆明冶金研究院昆明650031

由于无法对大型还原炉环状硅棒排布方式对能耗的影响做出准确判断,对42对棒西门子多晶硅还原炉进行仿真模拟计算,建立两种环状硅棒布棒方式(三环排布、四环排布)的还原炉模型。通过对还原炉的炉行为及棒行为分析发现,硅棒直径加大能耗... 详细信息

由于无法对大型还原炉环状硅棒排布方式对能耗的影响做出准确判断,对42对棒西门子多晶硅还原炉进行仿真模拟计算,建立两种环状硅棒布棒方式(三环排布、四环排布)的还原炉模型。通过对还原炉的炉行为及棒行为分析发现,硅棒直径加大能耗也会相应加大,且这种变化受炉内流场和温度场共同影响;同时,还原炉内内环硅棒辐射能耗随硅棒直径的增大呈先增大后减小的变化趋势,而排列在外环的硅棒辐射损耗则随硅棒直径的增大而不断增大。针对42对棒西门子还原炉内硅棒的排布方法,提出选用硅棒三环排布的方式可达到降低该还原炉总能耗的目的。

关键词：光伏发电数值模拟多晶硅辐射西门子还原炉节能降耗

人工智能预测急性缺血性脑卒中后出血转化的研究进展

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国际医学放射学杂志 2024年第2期47卷 160-164页

作者：张月谢刚李康(审校) 重庆医科大学重庆400016 中国科学院重庆绿色智能技术研究院中国科学院大学重庆学院重庆市人民医院放射科成都市第三人民医院放射科

急性缺血性卒中(AIS)致死、致残率高。出血转化(HT)是AIS的严重并发症,与临床治疗方案的选择及预后密切相关。人工智能(AI)技术作为一种能早期准确预测HT的新方法,其中影像组学能从CT、MRI等多种神经影像学数据中深度挖掘并提取与HT密... 详细信息

急性缺血性卒中(AIS)致死、致残率高。出血转化(HT)是AIS的严重并发症,与临床治疗方案的选择及预后密切相关。人工智能(AI)技术作为一种能早期准确预测HT的新方法,其中影像组学能从CT、MRI等多种神经影像学数据中深度挖掘并提取与HT密切相关的影像组学特征,通过机器学习和深度学习可以实现HT预测信息的筛选及相关性分析、预测模型的构建及优化,提高了HT的预测准确性。就影像组学、机器学习和深度学习预测AIS后HT的研究进展予以综述。

关键词：急性缺血性卒中出血转化人工智能深度学习预测

Theoretical Calculation for the Dip Feature in Tunnelling Experiment on Bi2212

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Chinese Physics Letters 2001年第9期18卷 1256-1257页

作者： xie gang HAN Ru-Shan Mesoscopic Physics Laboratory and Department of Physics Peking UniversityBeijing 100871

We generalize a model, which was presented by Norman [Phys. Rev. Lett. 79 (1997) 3506], to calculate the Bi2Sr2CaCu2Os+δ (Bi2212) single-electron tunnelling conductance. In our calculation result, the dip feature appears which has been widely observed in tunnelling experiments. It is found that this dip feature in tunnelling experiments and the dip/hump feature in angle-resolved photoemission experiments have a common physics. Moreover, it is shown from our numerical calculation method that if the spectral function A(κ, ω) is known, the tunnelling conductance can be obtained.

关键词： conductance Bi2212 calculation

Fabrication of palladium nanoparticles as effective catalysts by using supramolecular gels

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Chinese Chemical Letters 2016年第1期27卷 77-80页

作者： Wei Zhang Zhi-gang xie State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of Chinese Academy of Sciences Beijing 100049 China

Two-component supramolecular gels were made through self-assembly of tetrazolyl derivatives and Pd（OAc）_2. The robust gels indicated high storage modulus（〉10,000 Pa） and loss modulus, which were studied by rheological measurements. The formed Pd nanoparticles（~9 nm） obtained during the formation of the gel showed effective catalytic hydrogenation of nitrobenzene and could be recovered and reused without loss of activity.

关键词： Pd nanoparticles Self-assembly Supramolecular gels Catalysts

The Physical Property of Susceptibility for One-Dimensional Ferrimagnetic Chain with Alternating Spins 1 and 1/2 in Finite Magnetic Field

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Communications in Theoretical Physics 2001年第11期36卷 620-622页

作者： xie gang HAN Ru-Shan Mesoscopic Physics Lab and Department of Physics Peking UniversityBeijing 100871China Mesoscopic Physics Lab and Department of PhysicsPeking UniversityBeijing 100871China

We further calculate the dependence of xT on T in high magnetic fields,where X denotes susceptibility and T is temperature,using our previous research work - Green function's decoupling approximate approach,for the one-dimensional ferrimagnetic chain with alternating spins 1 and 1/*** find a linear correlation in certain range of magnetic field between the temperature of xT maximum and the magnetic ***,we simply analyze its physical meaning by our approach.

关键词： one-dimensional spin chain,susceptibility,ferrimagnetic,Green function

Model and Simulation of Multipath Error in DLL for GPS Receiver

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Chinese Journal of Electronics 2014年第3期23卷 508-515页

作者： CHENG Lan CHEN Jie xie gang Taiyuan University of Technology Education Ministry Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology

Although different multipath error models of Delay lock loop(DLL) used in GPS receiver are established, they have never been put together for comparison. Furthermore, no universal simulation method is developed to get a fair comparison among these models. A new model with implicate expression is hence proposed for the coherent DLL and the noncoherent Dot-product(DOT) power mode DLL. Meanwhile, a new simulation method based on the anonymous function in Matlab, which is especially suitable for models with implicit expression,is also proposed to compare the new model with the existing ones. The theoretical analysis and simulation results show that the existing models are the special case of the proposed one. The new simulation method can be used for the comparison of different multipath error models and the multipath error analysis of other DLLs for which only the implicit model is available.

关键词： Delay lock loop(DLL) Multipath Multipath error model Positioning system

TMAHS:a truthful multi-unit double auction framework for heterogeneous spectrum in secondary market

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The Journal of China Universities of Posts and Telecommunications 2019年第1期26卷 82-94页

作者： Li Xin xie gang Gao Jinchun School of Electrical Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications School of information and Communication Engineering Beijing University of Posts and Telecommunications

Auction was widely used to tackle spectrum allocation and sharing in the secondary market under the condition of spectrum scarcity. In real communication system, such as broadband communication, the utilization of spectrum resource is various because of different requirements and complex application scenarios. So, these schemes cannot be directly applied to the above wireless communication system. To solve this problem, a new model where sellers/buyers can sell/buy multi-unit for heterogeneous spectrum was proposed and a truthful multi-unit double auction framework was designed for heterogeneous spectrum trading. A valuation function is first applied to represent the buyer's true valuation of the sub-band and reflect the buyer's satisfaction degree and a novel concept termed ‘virtual player' was introduced. Then the buyer group was constructed based on the conflict graph to reuse the same spectrum among interference-free buyers in both spatial and temporal domains. The winner determination strategy and algorithm of clearing price were designed elaborately. According to the theoretical analysis, the scheme can satisfy three critical economic properties: truthfulness, individual rationality, and budget balance. Finally, simulation results show that the proposed scheme can achieve better user satisfaction, auction efficiency and spectrum reuse rate for the real communication system. The proposed auction framework is practical and effective.

关键词： spectrum auction double auction spectrum reuse heterogeneous spectrum multi-unit valuation function