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水声探测技术在火箭式深弹引信中的应用

弹箭与制导学报 2012年第1期32卷 99-101页

作者：伯华刘明楠江南机器集团有限公司湖南湘潭411207

一种水声近炸引信,适用于对鱼雷等水下目标实施拦截杀伤的火箭式深弹系统,设计中解决的技术问题有:对水下目标的识别技术、有效的测距方法及抗冲击过载技术。所采用的方法是通过对水下目标辐射噪声信号的能量检测、识别和能量变化的比... 详细信息

一种水声近炸引信,适用于对鱼雷等水下目标实施拦截杀伤的火箭式深弹系统,设计中解决的技术问题有:对水下目标的识别技术、有效的测距方法及抗冲击过载技术。所采用的方法是通过对水下目标辐射噪声信号的能量检测、识别和能量变化的比较以及目标所发出的不同线谱的频率来判断和识别目标。验证试验表明,能对不同目标进行识别,并适时发出起爆信号。

关键词：水声探测引信目标噪声识别

软岩巷道锚注支护结构弹塑性分析与有限元模拟

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人民长江 2014年第13期45卷 49-52页

作者：佘淑明刘闽南王晖山东省日照市岚山区巨峰水利站山东日照276812 山东农业大学水利土木工程学院山东泰安271018

为确定合理的软岩巷道锚注支护参数,以某煤矿深部软岩巷道锚注支护工程为例,根据锚注支护结构的嵌套力学分析模型,对锚注支护加固工程的锚注区范围、各分区的应力和位移进行了理论分析。在此基础上开展了三维有限元数值模拟和实际位移监... 详细信息

为确定合理的软岩巷道锚注支护参数,以某煤矿深部软岩巷道锚注支护工程为例,根据锚注支护结构的嵌套力学分析模型,对锚注支护加固工程的锚注区范围、各分区的应力和位移进行了理论分析。在此基础上开展了三维有限元数值模拟和实际位移监测,并将数值计算结果与理论分析结果、实际位移监测结果进行对比,三者吻合较好,证明了理论模型的合理性与数值方法的实用性。所提出的研究方法和结论可为锚注支护结构初步定量分析提供借鉴。

关键词：嵌套力学分析模型软岩巷道锚注支护

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1957年日本废除“中国差别”政策与对美交涉——以日本解密档案为中心的考察

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史林 2024年第2期 45-55,217页

作者：李明楠湖南师范大学历史文化学院 410081

为了缓解经济危机并应对冷战缓和形势,1957年日本岸信介政府决定放宽对华出口管制标准、废除“中国差别”政策,以现实主义态度增进对华贸易,但美国却坚持意识形态偏见和对华遏制思维,反对这一决定。日本凭借各种有利条件,利用英、法等... 详细信息

为了缓解经济危机并应对冷战缓和形势,1957年日本岸信介政府决定放宽对华出口管制标准、废除“中国差别”政策,以现实主义态度增进对华贸易,但美国却坚持意识形态偏见和对华遏制思维,反对这一决定。日本凭借各种有利条件,利用英、法等国与美国的矛盾,并从国民情绪、地缘均势、防共战术与同盟义务等方面开展对美交涉。为维护美日关系以及西方阵营的稳定,美国被迫默许日本可以单独行事,而日本既参考英国等国的行动,又主动稳定对美关系,数次调整目标,最后推迟至1957年7月才采取行动。日本废除“中国差别”政策的过程揭示出1950年代后期美日关系的重要变动,以及日本对华经济政策背后所隐藏的“两个中国”意图。

关键词：岸信介 “中国差别”政策出口管制美日关系 “两个中国”政策

The cloning,expression,purification and some characteristic of SARS NP828859.1 protein

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The cloning,expression,purification and some characteristic ...

Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

The Third Asian Conference on Vision (ACV2004)

作者： Wen Li Ying liu Yang liu Lei Lan mingnan liu Rong Qiao He Lab of Visual Information Processing, Center for Brain and Cognition Sciences, Institute of Biophysics, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, China,

NP28859.1 (NP9) of SARS Coronavirus (Canada), a putative uncharacterized protein, has been cloned from SARS genome 28115-28411 with a length of 99 amino acid residues (11KD). The PCR fragment was inserted to pET32a vector and expressed in Origami BL21 after IPTG induce. The expressed fusion protein was purified by Ni-NTA agarose affinity chromatography, and rEK was used to cleave the his-tag. SDS-PAGE shows the cleaved protein is 11 KD. Protein sequencing has proved that the N-terminal stretch is A-M-D-P-N, which is the same as predicted by the nucleotide sequence.

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC ***,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC ***,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is ***,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind *** simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during ***:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during ***:Sixteen RCTs with a cumulative sample size of 1178 cases were *** these,964 patients were included in the *** Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low ***:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively ***,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

Stochastic Unit Commitment with High-Penetration Offshore Wind Power Generation in Typhoon Scenarios

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 535-546页

作者： Yanqi liu Dundun liu Hongcai Zhang State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao 999078China University of Macao Zhuhai UM Science and Technology Research Institute ZhuhaiChina

To tackle the energy crisis and climate change,wind farms are being heavily invested in across the *** China's coastal areas,there are abundant wind resources and numerous offshore wind farms are being *** secure operation of these wind farms may suffer from typhoons,and researchers have studied power system operation and resilience enhancement in typhoon ***,the intricate movement of a typhoon makes it challenging to evaluate its spatial-temporal *** published papers only consider predefined typhoon trajectories neglecting *** address this challenge,this study proposes a stochastic unit commitment model that incorporates high-penetration offshore wind power generation in typhoon *** adopts a data-driven method to describe the uncertainties of typhoon trajectories and considers the realistic anti-typhoon mode in offshore wind farms.A two-stage stochastic unit commitment model is designed to enhance power system resilience in typhoon *** formulate the model into a mixed-integer linear programming problem and then solve it based on the computationally-efficient progressive hedging algorithm(PHA).Finally,numerical experiments validate the effectiveness of the proposed method.

关键词： Unit commitment two-stage stochastic programming offshore wind farm typhoon

Devolatilization of high viscous fluids with high gravity technology

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Chinese Journal of Chemical Engineering 2024年第7期71卷 249-257页

作者： Jibing Qi Youzhi liu Yandong liu Taiyuan University Taiyuan 030032China Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

Volatile organic compounds(VOCs)are generally toxic and harmful substances that can cause health and environmental *** removal of VOCs from polymers has become a key *** effective devolatilization to remove VOCs from high viscous fluids such as polymer is necessary and is of great *** this study,the devolatilization effect of a rotating packed bed(RPB)was studied by using polydimethylsiloxane as the viscous fluid and acetone as the *** devolatilization rate and liquid phase volume(KLa)have been *** results indicated that the optimum conditions were the high-gravity factor of 60,liquid flow rate of 10 L·h^(-1),and vacuum degree of 0.077 *** dimensionless correlation of KLa was established,and the deviations between predicted and experimental values were less than±28%.The high-gravity technology will result in lower mass transfer resistance in the devolatilization process,enhance the mass transfer process of acetone,and improve the removal effect of *** work provides a promising path for the removal of volatiles from polymers in combination with high-gravity *** can provide the basis for the application of RPB in viscous fluids.

关键词： High-gravity technology Devolatilization rate High viscous fluid Volatile organic compounds(VOCs)