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Journal of Geoscience and Environment Protection 2018年第8期6卷 25-37页

作者： dehe liu Jingfei You Qijie Xie Yuanyuan Huang Huajun Tong Yongchun County Meteorological Bureau of Fujian Province Yongchun China Quanzhou Meteorological Bureau of Fujian Province Quanzhou China Nan’an Meteorological Bureau of Fujian Province Nan’an China

To analyze the characteristics of drought and flood variations in Quanzhou during recent 55 years, the standardized precipitation index (SPI) and Empirical Orthogonal Function (EOF) and Rotated Empirical Orthogonal Function (REOF) were calculated by using the monthly precipitation data from 6 meteorological bureaus across Quanzhou for 1960-2014. Results showed that: 1) During 1960-2014, the drought and flood showed Periodic variation characteristics in Quanzhou, the specific period of frequent drought was 1963-1972, 1977-1986 and 2009-2011, and the specific period of frequent flood was 1961-1962, 1972-1975, 1990-1992 and 1997-2007;the drought and flood did not have significant tendency of variation in Spring and Summer, and the drought and flood showed a non-significant downward trend in Autumn and Winter. 2) The drought and flood variation had relatively consistent trend in Quanzhou, but there was a big difference on the northwest mountainous area, the middle semi-mountainous area and the southeast coast area in some periods. 3) The precipitation cell and distribution in every season were Nan’an and Anxi, but there was a big difference in rainfall less area: it was Yongchun and Dehua in Spring, Chongwu and Jinjiang in Summer, Chongwu in Autumn, Dehua and Chongwu in Winter.

关键词： Standardized Precipitation Index Drought and Flood Empirical Orthogonal Function (EOF) Rotated Empirical Orthogonal Function (REOF)

辽宁辽阳地区辽河群酸性火山岩锆石U-Pb年代学及其地质意义

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岩石学报 2017年第9期33卷 2792-2810页

作者：陈井胜邢德和刘淼李斌杨浩田德欣杨帆汪岩中国地质调查局沈阳地质调查中心沈阳110034 吉林大学地球科学学院长春130061 辽宁省矿产勘查院沈阳110032

辽宁省辽阳地区出露有大面积的古元古代辽河群地层,在辽河群里尔峪组及高家峪组中识别出一套酸性火山岩。本文通过对酸性火山岩同位素年代学及地球化学研究,用以限定辽河群形成时代,并进一步探讨其形成的动力学背景。这套酸性火山岩岩... 详细信息

辽宁省辽阳地区出露有大面积的古元古代辽河群地层,在辽河群里尔峪组及高家峪组中识别出一套酸性火山岩。本文通过对酸性火山岩同位素年代学及地球化学研究,用以限定辽河群形成时代,并进一步探讨其形成的动力学背景。这套酸性火山岩岩性包括流纹岩、变流纹质含角砾凝灰岩、角岩化流纹岩和弱硅化流纹岩,对其中6件样品利用LA-ICP-MS锆石U-Pb方法测年。CL图像显示辽河群酸性火山岩中的锆石均具典型的岩浆振荡环带结构和较高的Th/U比值,显示为岩浆锆石。锆石U-Pb年龄可分为3期:2190~2180Ma、2110~2100Ma、1970~1960Ma,结合其中存在继承锆石的结果认为辽河群至少存在3期岩浆活动,将辽河群形成时代限制于2.19~1.96Ga,其形成时代大约持续了230Myr左右。野外接触关系的观察及酸性火山岩的年代学特征从另一个方面揭露辽河群总体为一套无序、局部有序的构造地层,各岩组间不存在上下关系。前人研究表明"辽吉花岗岩"形成年龄为2.16Ga,通过野外观察其与辽河群之间均为构造接触。D1442-1和D1444-2两个样品锆石U-Pb测年结果为2180±12Ma、2190±13Ma,均略早于"辽吉花岗岩",结合其与辽河群野外关系,认为"辽吉花岗岩"应该不是作为沉积基底,而是与辽河群为同一构造运动的产物。辽河群流纹岩Al_2O_3含量16.33%~16.90%,K_2O含量4.62%~4.77%,K_2O+Na_2O含量5.97%~7.54%,含铝指数(A/CNK)比较高为1.27~1.50,为过铝质岩石,显示富铝、高钾特征。此外流纹岩轻稀土富集,重稀土亏损,轻重稀土分馏明显,具有明显的负铕异常,亏损Ba、Sr、Ti,较高的Zr及(Zr+Nb+Ce+Y)含量、10000Ga/Al比值等特点都显示为A型花岗岩,说明其形成于地壳减薄环境。本文在辽河群中识别出一套酸性火山岩与前人在南辽河群识别出的变质流纹岩组成了酸性端元(2201~1960Ma),同时期存在的基性火成岩(2198~1869Ma)为基性端元,证明了辽河群"双峰式火山岩"的存在,暗示辽河群形成于伸展拉张环境。

关键词：辽阳辽河群酸性火山岩锆石U-Pb年代学构造背景

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地面激光扫描技术在古石拱桥建模中的应用

激光杂志 2018年第2期39卷 101-104页

作者：刘德贺史玉峰南京林业大学土木工程学院

针对一些历史久远的古石拱桥缺乏可靠的设计资料,难以高效地识别其详细的整体几何特征等问题,提出一种利用地面激光扫描（TLS）技术对其进行建模的方法。首先应用TLS技术采集古石拱桥整体三维点云数据,然后采用基于几何特征的拼接方法... 详细信息

针对一些历史久远的古石拱桥缺乏可靠的设计资料,难以高效地识别其详细的整体几何特征等问题,提出一种利用地面激光扫描（TLS）技术对其进行建模的方法。首先应用TLS技术采集古石拱桥整体三维点云数据,然后采用基于几何特征的拼接方法对多视点点云数据进行配准、去噪和精简,采用NURBS算法对石拱构件进行提取、拟合和曲面重建,构建出石拱桥三维实体模型。结果表明,利用TLS技术可以全面、准确地获取石拱桥点云数据,实现对石拱桥三维建模,为古石拱桥几何结构监测、加固和复原提供了基础数据。

关键词：地面激光扫描激光点云古石拱桥点云数据处理 NURBS

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浅谈篮球运动核心力量的作用与训练方法

当代体育科技 2016年第10期6卷 51-52页

作者：刘德鹤江西吉安白鹭洲中学江西吉安343000

该文运用文献资料、逻辑分析、专家访谈等方法进行研究,结合多年的训练实践经验,以人体解剖学、运动生理学、运动训练学等理论为基础,阐述了核心力量训练对篮球运动员所起的作用,并提出了相应的科学训练方法。

关键词：篮球运动核心力量训练方法作用

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预防性环境民事公益诉讼的功能越位及矫正

河北环境工程学院学报 2023年第3期33卷 26-31页

作者：熊超刘德和广西大学法学院广西南宁530004

风险社会促使环境司法从事后救济向事前预防转型。在“单轨制”预防性环境公益诉讼体系下,预防性环境民事公益诉讼成为司法权规制环境风险的唯一路径。我国立法现状造成了预防性环境民事公益诉讼承担监督矫正职能、与环境行政执法重复... 详细信息

风险社会促使环境司法从事后救济向事前预防转型。在“单轨制”预防性环境公益诉讼体系下,预防性环境民事公益诉讼成为司法权规制环境风险的唯一路径。我国立法现状造成了预防性环境民事公益诉讼承担监督矫正职能、与环境行政执法重复处理等功能越位的制度窘境。“单轨制”的预防性环境公益诉讼体系进一步导致风险规制中司法权与行政权的失衡。因此,为了矫正“功能越位”的制度困境以及平衡司法权和行政权的关系,需要从内部和外部两个路径对预防性环境民事公益诉讼制度进行矫正。

关键词：预防性环境民事公益诉讼风险社会风险预防环境司法

Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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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

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

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

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)