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Method to Determine the Propulsion Characteristics of a Ship Moving in Ice
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作者 Kirill Sazonov Grigorii Kanevskii +1 位作者 Alexandr Klubnichkin Aleksei Dobrodeev 《哈尔滨工程大学学报(英文版)》 2025年第3期532-541,共10页
In designing modern vessels, calculating the propulsion performance of ships in ice is important, including propeller effective thrust, number of revolutions, consumed power, and ship speed. Such calculations allow fo... In designing modern vessels, calculating the propulsion performance of ships in ice is important, including propeller effective thrust, number of revolutions, consumed power, and ship speed. Such calculations allow for more accurate prediction of the ice performance of a designed ship and provide inputs for designers of ship power and automation systems. Preliminary calculations of ship propulsion and thrust characteristics in ice can enable predictions of full-scale ice resistance without measuring the propeller thrust during sea trials. Measuring propeller revolutions,ship speed, and the power delivered to propellers could be sufficient to determine the propeller thrust of the vessel. At present, significant difficulties arise in determining the thrust of icebreakers and ice-class ships in ice conditions. These challenges are related to the fact that the traditional system of propeller/hull interaction coefficients does not function correctly in ice conditions. The wake fraction becomes negative and tends to minus infinity starting from a certain value of the propeller advance coefficient. This issue prevents accurate determination of the performance characteristics, thrust, and rotational speed of the propulsors. In this study, an alternative system of propeller/hull interaction coefficients for ice is proposed. It enables the calculation of all propulsion parameters in ice based on standard hydrodynamic tests with selfpropulsion models. An experimental method is developed to determine alternative propeller/hull interaction coefficients. A prediction method is suggested to determine propulsion performance in ice based on the alternative interaction coefficient system. A case study applying the propulsion prediction method for ice conditions is provided. This study also discusses the following issues of ship operation in ice: the scale effect of icebreaker propellers and the prospects for introducing an ice interaction coefficient. 展开更多
关键词 ICEBREAKER Model experiment Interaction coefficients Propeller Calculation Off-design mode Propulsion characteristics Ship moving in ice
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An Aircraft Icing Detection Method Based on Performance Data of Rotor
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作者 WU Yuan ZHU Dongyu +1 位作者 XU Lingsong YU Lei 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期212-225,共14页
Existing icing detection technologies face challenges when applied to small and medium-sized aircraft,especially electric vertical take-off and landing(eVTOL)aircraft that meet the needs of low-altitude economic devel... Existing icing detection technologies face challenges when applied to small and medium-sized aircraft,especially electric vertical take-off and landing(eVTOL)aircraft that meet the needs of low-altitude economic development.This study proposes a data-driven icing detection method based on rotor performance evolution.Through dry-air baseline tests and dynamic icing comparative experiments(wind speed 0—30 m/s,rotational speed 0—3000 r/min,collective pitch 0°—8°)of a 0.6 m rotor in the FL-61 icing wind tunnel,a multi-source heterogeneous dataset containing motion parameters,aerodynamic parameters,and icing state identifiers is constructed.An innovative signal processing architecture combining adaptive Kalman filtering and moving average cascading is adopted.And a comparative study is conducted on the performance of support vector machine(SVM),multilayer perceptron(MLP),and random forest(RF)algorithms,achieving real-time identification of icing states in rotating components.Experimental results demonstrate that the method exhibits a minimum detection latency of 6.9 s and 96%overall accuracy in reserved test cases,featuring low-latency and low false-alarm,providing a sensor-free lightweight solution for light/vertical takeoff and landing aircraft. 展开更多
关键词 ROTOR PROPELLER aircraft icing icing detection machine learning support vector machine(SVM) multilayer perceptron(MLP)
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Facial detection of formaldehyde by using acidichromic carbon dots and the reaction between formaldehyde and ammonium chloride
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作者 Quanxing Mao Zhengliang Wang +5 位作者 Zhinan Hu Ziqi Yang Hui Li Yali Yao Zijun Yong Tianyi Ma 《Chinese Chemical Letters》 2025年第7期262-265,共4页
Herein we report the facial detection of formaldehyde(FA)by using an interesting red acidichromic carbon dots(ACDs)which turns blue when pH gradually decreases.The color change was attributed to the conversion between... Herein we report the facial detection of formaldehyde(FA)by using an interesting red acidichromic carbon dots(ACDs)which turns blue when pH gradually decreases.The color change was attributed to the conversion between the double bonds(C=N)and single bonds(C-N)on the surface of the ACDs.Inspired by the reaction between FA and ammonium chloride that produces H^(+)and methenamine and decrease the pH value of the solution,a fast and simple visual detection method for FA was found with a minimum discriminated concentration of 0.04 mol/L.A fluorescence detection method for FA was also found with LOD of 0.029 mol/L and FA in real sample,e.g.,shredded squid was successfully analyzed.This work provides a new idea of developing fast visual detection method for daily monitor or in-site semiquantitative assessment on FA. 展开更多
关键词 Acidichromic feature Carbon dots FORMALDEHYDE Visual detection Indirect analysis
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Modulation of rice grain shape and appearance by the GS10-encoded long coiled-coil protein
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作者 Yanmin Luo Yuyu Chen +12 位作者 Pao Xue Beifang Wang Yiwei Kang Yue Zhang Daibo Chen Yongbo Hong Weixun Wu Qunen Liu Xiaodeng Zhan Yongjun Lin Shihua Cheng Yingxin Zhang Liyong Cao 《The Crop Journal》 2025年第1期158-169,共12页
Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased clonin... Rice grain size is a primary characteristic essential for artificial domestication and breeding,governed by grain length,width,and thickness.In this study,we cloned Grain Size 10(GS10),a novel gene via mapbased cloning.Biochemical,molecular,and genetic studies were performed to elucidate the GS10 involved grain size mechanism in rice.Mutant of GS10 lead to reduced grain size due to alterations in cell expansion.Additionally,GS10 is responsible for the formation of notched-belly grains,especially in smaller grain varieties possessing loss-function mutations.Overexpression of GS10 in Nipponbare results in increasing grain length,grain weight and improve the appearance quality of rice.GS10 encodes conserved protein with uncharacterized function.Furthermore,GS10 regulates the grain size by interacting OsBRICK1,a subunit of the WAVE complex that governs actin nucleation and affects the assembly of microfilaments in rice.Together,our study demonstrates that,GS10 positively regulates the grain length and grain weight,which is beneficial for further improvements in yield characteristics. 展开更多
关键词 GS10 Grain size Grain weight Appearance quality MICROFILAMENTS
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The Impact of Tropical Convective Heating on the Amundsen Sea Low in a Deep-Learning Weather Forecasting Model
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作者 Yibin HUANG Zhen-Qiang ZHOU +2 位作者 Renhe ZHANG Xiaohui ZHONG Hao LI 《Advances in Atmospheric Sciences》 2025年第12期2411-2421,共11页
Data-driven deep-learning models have shown outstanding performance in global weather forecasting.Understanding the dynamic response processes within these models is crucial for comprehending the embedded physical pro... Data-driven deep-learning models have shown outstanding performance in global weather forecasting.Understanding the dynamic response processes within these models is crucial for comprehending the embedded physical processes and sources of predictability.By applying the classic tropical steady heating experiment to the Pangu-Weather deep-learning model during the austral winter background state,we observe a classic Matsuno-Gill response in the tropics and planetary Rossby waves propagating to the polar regions.The results of the Pangu-Weather model are consistent with those of traditional physics-based general circulation models(GCMs):convective heating forcing in the tropical Atlantic and western Indian Ocean,and convective cooling forcing in the Maritime Continent all deepen the Amundsen Sea Low(ASL),while convective heating forcing in the western Pacific weakens the ASL.The Pangu-Weather model has learned that these tropical basins jointly and linearly regulate the atmospheric circulation around West Antarctica through Rossby waves.However,the Pangu-Weather model overestimates(underestimates)atmospheric responses of heating in the tropical Pacific(Indian and Atlantic)Ocean compared with traditional GCMs,with a much larger contribution of Pacific heating forcing than other basins in changes of the ASL.The physics learned from reanalysis data may be the source of these deep-learning models’predictability,and the accuracy of extended-range forecasting and the potential of seasonal forecasting using deep-learning models may be influenced by overestimation or underestimation of the role of the tropical Pacific,Indian,and Atlantic Oceans. 展开更多
关键词 deep learning Pangu-Weather Amundsen Sea Low Rossby wave austral winter
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基于Simulink电液比例位置控制系统的性能分析和优化 被引量:2
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作者 高振军 张加恒 +5 位作者 李文杨 何国斌 刘海 冯威 Oybek Ishnazarov Martina Zelenakova 《西华大学学报(自然科学版)》 CAS 2024年第5期88-95,共8页
为改善某钢铁公司电液比例位置控制系统相关系统性能,文章使用数值计算分析方法,建立电液比例位置控制系统的数学模型,通过Simulink软件构建模型,并分析可知,系统的幅值裕度为25 dB,相位裕度为89.6°,结合伯德图的曲线特征,发现该... 为改善某钢铁公司电液比例位置控制系统相关系统性能,文章使用数值计算分析方法,建立电液比例位置控制系统的数学模型,通过Simulink软件构建模型,并分析可知,系统的幅值裕度为25 dB,相位裕度为89.6°,结合伯德图的曲线特征,发现该系统的准确性与稳定性已满足基本要求,但通过系统的阶跃响应曲线,发现其上升时间为4.26 s、调整时间为5.83 s,系统响应的快速性没有达到要求。为进一步改进系统性能,选取结构简单、适用范围广的PID控制器,通过添加PID控制和不断修改PID控制器参数,优化系统性能,优化后的系统幅值裕度为5.18 dB,相位裕度90°,上升时间为0.236 s,调整时间为0.435 s,系统在保持良好的准确性和稳定性的基础上,快速性也得到了改善,已完全满足工业生产的要求。最后讨论了液压缸有效面积对PID控制性能的影响:A_(h)=0.15~0.20 m^(2)时系统性能仍有较好的适用性;小于0.15 m^(2)时会发生剧烈震动;大于0.20 m^(2)会大大增加响应时间。 展开更多
关键词 电液比例位置控制系统 SIMULINK仿真 PID控制 Tuner优化
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2024年全球数字化营销风向 被引量:1
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作者 《中国眼镜科技杂志》 2024年第4期78-79,共2页
在数字化时代的浪潮中,数据成为塑造市场趋势的关键驱动力。随着全球营销界的不断探索和发展,人工智能逐渐成为营销人员的得力助手,更导致了市场格局的快速演变。那么,2024年,全球数字化营销有哪些风向与趋势?
关键词 数字化营销 全球营销 人工智能 数字化时代 市场趋势 营销人员 驱动力 风向
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A review of the BuFeng-1 GNSS-R mission:calibration and validation results of sea surface and land surface 被引量:2
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作者 Cheng Jing Weiqiang Li +9 位作者 Wei Wan Feng Lu Xinliang Niu Xiuwan Chen Antonio Rius Estel Cardellach Serni Ribó Baojian Liu Zhizhou Guo Yang Nan 《Geo-Spatial Information Science》 CSCD 2024年第3期638-652,共15页
In this paper,we will conclude the results of Bufeng-1(BF-1)A/B data processing,calibration workflow,and validation of the calibrated sea surface winds,land surface soil moisture,and sea surface height measurements.Si... In this paper,we will conclude the results of Bufeng-1(BF-1)A/B data processing,calibration workflow,and validation of the calibrated sea surface winds,land surface soil moisture,and sea surface height measurements.Since 2019,the BF-1 mission has operated in-orbit for over 4 years.The Earth reflected delay Doppler maps(DDMs)are continuously collected to perform global sea surface and land observations.At the same time,the intermediate frequency(IF)raw data are also obtained for 12 seconds every pass in diagnostic mode.To begin with,a brief description of the spaceborne Global Navigation Satellite System Reflectometry(GNSS-R)technique will be provided in the introduction.Next,we will present the overview of Chinese BF-1 mission and the data specifications used in our research.In the next section,the BF-1 mission-related spaceborne power calibration and validation are presented to show the support to power DDM observable production for sea surface and land surface applications.Then,the status of Chinese Beidou System(BDS)Equivalent Isotropic Radiated Power(EIRP)acquisition programme is then introduced.Furthermore,the latest sea surface height(SSH)measurements results including two modes(group delay and carrier phase)and wind speed derivation based on machine learning(ML)method will be spatial-temporal aligned and validated with auxiliary datasets including Denmark Technology University(DTU)mean sea surface(MSS)products and European Centre for Medium-Range Weather Forecasts(ECMWF)ERA5 reanalysis.The previous published results of sea surface winds retrieval under Hurricane conditions and soil moisture retrieval are also reviewed for the BF-1 mission applications.Finally,the conclusion of BF-1 derived results will be discussed to draw out ongoing/future works. 展开更多
关键词 Global Navigation Satellite System-Reflectometry(GNSS-R) Delay-Doppler Map(DDM) sea surface height(SSH) soil moisture sea surface wind speed Bufeng-1 Immediate Frequency(IF)
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Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber
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作者 Yi Tu Yuan Wu Yu Zeng 《Fluid Dynamics & Materials Processing》 EI 2024年第5期989-1014,共26页
The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic consequences.The Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annula... The formation of ice on the leading edge of aircraft engines is a serious issue,as it can have catastrophic consequences.The Swirl Anti-Icing(SAI)system,driven by ejection,circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent icing.This study employs a validated Computational Fluid Dynamics(CFD)approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing chamber.Additionally,the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the system.The research findings indicate that,within the considered flow range,reducing the nozzle specific areaφfrom 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%.This enhancement increases the air circulating rate,thereby intensifying convective heat transfer within the SAI chamber.However,the reduction inφalso leads to a significant increase in the required bleed air pressure and a higher entropy generation rate,indicating lower exergy efficiency.The nozzle angleθnotably affects the distribution of hot and cold spots on the lip surface of the SAI chamber.Increasingθfrom 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K. 展开更多
关键词 Swirl anti-icing heat transfer exergy efficiency hot and cold spot aircraft engine
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穿越时空的艺术对话——天津标准眼镜博物馆部分藏品赏析(下)
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作者 《中国眼镜科技杂志》 2024年第12期80-84,共5页
在历史的长卷中,眼镜的演变汇聚了人类智慧与工艺的精华。为广泛传播眼镜文化,弘扬手工艺传承精神,追溯并展现眼镜发展的历史脉络,天津市标准眼镜有限公司创立了该市首家眼镜主题博物馆。该馆馆藏丰富,涵盖两千余套珍贵展品,按历史朝代... 在历史的长卷中,眼镜的演变汇聚了人类智慧与工艺的精华。为广泛传播眼镜文化,弘扬手工艺传承精神,追溯并展现眼镜发展的历史脉络,天津市标准眼镜有限公司创立了该市首家眼镜主题博物馆。该馆馆藏丰富,涵盖两千余套珍贵展品,按历史朝代进程,分别设置了相应展品的展柜。通过眼镜的历史沿革与文化背景,向公众展现了眼镜的发展轨迹及其在文明演进中的角色。 展开更多
关键词 主题博物馆 文明演进 人类智慧 眼镜 藏品 历史沿革 穿越时空 发展轨迹
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祁连山区黑河上游多年冻土分布考察 被引量:30
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作者 王庆峰 张廷军 +6 位作者 吴吉春 彭小清 钟歆玥 牟翠翠 王康 吴青柏 程国栋 《冰川冻土》 CSCD 北大核心 2013年第1期19-29,共11页
高山多年冻土的分布及土壤季节冻融过程对地表水文过程、生态系统、碳循环及寒区工程建设等都有很大的影响.黑河上游地处祁连山中东部,属于高原亚寒带半干旱气候,研究黑河流域多年冻土分布对于系统理解该区域的生态-水文过程、气候与环... 高山多年冻土的分布及土壤季节冻融过程对地表水文过程、生态系统、碳循环及寒区工程建设等都有很大的影响.黑河上游地处祁连山中东部,属于高原亚寒带半干旱气候,研究黑河流域多年冻土分布对于系统理解该区域的生态-水文过程、气候与环境变化以及水资源评价、工程建设等非常重要.2011年6—8月对黑河干流源头西支开展了多年冻土调查,沿二尕公路(S204)在热水大坂垭口至石棉矿岔口之间区域,完成测温孔7眼,并布设测温管进行地温监测.根据勘察、钻探及测温资料,确定了黑河源头地区山地多年冻土下界为海拔3 650~3 700m之间.受高度地带性的控制,随着海拔的降低,活动层厚度由在海拔4 132m时的1.6m增加至在多年冻土下界处的约4.0m,多年冻土年平均地温也相应的由-1.7℃增加到0.0℃左右,而多年冻土厚度由100m以上减小到多年冻土下界处的0.0m.同时,坡度和坡向、岩性、含水(冰)量、地下水、河水等局地因素对多年冻土温度和厚度也有重要的作用. 展开更多
关键词 多年冻土下界 活动层 海拔 年平均地温 黑河流域
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祁连山区黑河上游俄博岭多年冻土区活动层碳储量研究 被引量:18
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作者 牟翠翠 张廷军 +3 位作者 曹斌 万旭东 彭小清 程国栋 《冰川冻土》 CSCD 北大核心 2013年第1期1-9,共9页
为了探索在全球气候变化背景下多年冻土区碳储量现状,通过野外实地勘探和室内实验,对黑河上游俄博岭多年冻土区地貌特征及不同海拔活动层内的碳储量进行考察和估算.结果表明:黑河上游俄博岭冰缘现象显著,土壤季节冻融过程活跃,且活动层... 为了探索在全球气候变化背景下多年冻土区碳储量现状,通过野外实地勘探和室内实验,对黑河上游俄博岭多年冻土区地貌特征及不同海拔活动层内的碳储量进行考察和估算.结果表明:黑河上游俄博岭冰缘现象显著,土壤季节冻融过程活跃,且活动层中碳储量丰富.在研究区约2.5×106 m2的范围内,活动层平均厚度约为1.1m,活动层土壤有机质平均含量约为72.1%,碳储量估算约为1.57Mt C.活动层不同深度处有机质含量呈现不同的变化规律.随着活动层深度增加,土壤有机质的含量逐渐降低,在多年冻土上限附近有机质含量较高.另外,活动层有机质含量随着海拔和土壤含水量的不同而变化,同时多年冻土区微地形和地质条件也对有机质含量具有重要的影响. 展开更多
关键词 活动层 气候变暖 有机质含量 碳储量估算
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欧亚大陆积雪分布及其类型划分 被引量:45
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作者 张廷军 钟歆玥 《冰川冻土》 CSCD 北大核心 2014年第3期481-490,共10页
利用1966-2012年欧亚大陆1 152个地面气象台站积雪深度资料,对欧亚大陆积雪深度、累计积雪天数和连续积雪天数的空间分布进行了分析,以连续积雪天数为标准对欧亚大陆季节性积雪类型进行了划分,并与应用累计积雪天数对积雪区类型的划分... 利用1966-2012年欧亚大陆1 152个地面气象台站积雪深度资料,对欧亚大陆积雪深度、累计积雪天数和连续积雪天数的空间分布进行了分析,以连续积雪天数为标准对欧亚大陆季节性积雪类型进行了划分,并与应用累计积雪天数对积雪区类型的划分进行了比较研究.结果表明:欧亚大陆积雪分布具有显著纬度地带性特征,积雪深度、累计积雪天数和连续积雪天数的大值分布区均位于俄罗斯平原的东北部、科拉半岛、西西伯利亚平原、中西伯利亚高原以及俄罗斯远东北部大部分区域.与累计积雪天数划分方法相比,利用连续积雪天数对欧亚大陆季节性积雪分区,在前苏联地区积雪类型分区差异并不显著,但蒙古和中国的稳定积雪区明显缩减,青藏高原无稳定积雪区,中国大部分地区为非周期性不稳定积雪区.两种积雪分区划分方法比较结果显示,连续积雪天数划分方法更能体现积雪累积的连续性和持久性,更符合对稳定积雪和不稳定积雪的划分标准. 展开更多
关键词 积雪深度 积雪天数 积雪类型 欧亚大陆
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基于准则分析的工程伦理教育探讨 被引量:6
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作者 张满 王孙禺 《高等工程教育研究》 CSSCI 北大核心 2017年第4期68-72,共5页
本文基于对高校教师与工程师样本群体的调查与实证研究,建构了工程伦理准则的体系,分析了两个不同群体的认同差异。通过探索性因子分析发现,工程伦理准则体系由"工作精神"、"品行特征"、"工作宗旨"和&qu... 本文基于对高校教师与工程师样本群体的调查与实证研究,建构了工程伦理准则的体系,分析了两个不同群体的认同差异。通过探索性因子分析发现,工程伦理准则体系由"工作精神"、"品行特征"、"工作宗旨"和"责任品质"四个维度构成;通过独立样本检验的差异分析和重要性排序结果的分析发现,高校伦理教育者与工程师两个群体在工程伦理准则内容选择方面存在明显差异。作者基于工程伦理准则体系的实证结果、高校教师与工程师本身对于工程伦理准则体系认同的差异性,提出了改进中国工程伦理教育的相关建议。 展开更多
关键词 工程伦理教育 工程伦理准则 教育改革 人才培养与开发
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中国1956—2006年地表土壤冻结天数时空分布及其变化特征 被引量:12
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作者 王康 张廷军 《地球科学进展》 CAS CSCD 北大核心 2013年第11期1269-1275,共7页
应用中国境内845个气象台站的地表日最低温度资料,计算分析了近地表土壤冻结天数在1971—2000年的气候平均值;探讨了其空间的分布特征及其与冻土分布的关系;构建并分析了1956—2006年地表土壤冻结天数的时间序列及其与气侯变化的关系。... 应用中国境内845个气象台站的地表日最低温度资料,计算分析了近地表土壤冻结天数在1971—2000年的气候平均值;探讨了其空间的分布特征及其与冻土分布的关系;构建并分析了1956—2006年地表土壤冻结天数的时间序列及其与气侯变化的关系。结果表明,中国境内近地表土壤冻结天数的气候平均值随纬度增加、海拔升高而增加。青藏高原、新疆北部和东北地区北部多年平均冻结天数均超过200天。多年冻土区的边界与冻结天数(220±10)天的等值线高度吻合。按冻结天数大于15天为季节冻土区的定义,中国季节冻土的最南界约为25°N,22°N以南地区基本为非冻结区。自1956年以来,中国境内近地表土壤冻结天数呈显著的下降趋势,变化速率为-0.22 d/a,但20世纪90年代以后,其减少速率可达-1.02 d/a。近地表土壤冻结天数的变化与气温变化呈负相关关系,即随气温升高近地表土壤冻结天数减少。 展开更多
关键词 土壤表面 冻结天数 气候变化 地表温度 冻土
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我国冰冻圈及其变化的脆弱性与评估方法 被引量:15
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作者 杨建平 张廷军 《冰川冻土》 CSCD 北大核心 2010年第6期1084-1096,共13页
基于脆弱性研究文献,从脆弱性概念、评估内容、评估方法等方面系统总结了脆弱性评估研究的特点和趋势,开展脆弱性评估时应注意的系统、关注特征、灾害、尺度与时间等五个方面,剖析了区域尺度脆弱性评估涉及的一系列问题,介绍了脆弱性评... 基于脆弱性研究文献,从脆弱性概念、评估内容、评估方法等方面系统总结了脆弱性评估研究的特点和趋势,开展脆弱性评估时应注意的系统、关注特征、灾害、尺度与时间等五个方面,剖析了区域尺度脆弱性评估涉及的一系列问题,介绍了脆弱性评估方法及其优缺点和适用性.探讨了我国冰冻圈及其变化的脆弱性概念,分析了二者之间的关系,论述了我国冰冻圈及其变化的脆弱性评估内容、评估尺度和评估方法. 展开更多
关键词 脆弱性 冰冻圈的脆弱性 冰冻圈变化的脆弱性 脆弱性评估方法
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中国寒区水文学研究的新阶段——记我国杰出寒区水文学家叶柏生研究员的创新与贡献 被引量:7
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作者 丁永建 刘时银 +6 位作者 刘凤景 杨大庆 张廷军 赵林 沈永平 阳坤 张世强 《冰川冻土》 CSCD 北大核心 2012年第5期1009-1022,共14页
我国杰出的寒区水文学家叶柏生研究员不幸因公殉职.选取了叶柏生研究员若干代表性研究成果,包括与他人的合作研究成果,重点从冰川水文、冻土水文和区域水文变化三方面总结了其对寒区水文学发展所做的创新与贡献.文章列出了每项研究成果... 我国杰出的寒区水文学家叶柏生研究员不幸因公殉职.选取了叶柏生研究员若干代表性研究成果,包括与他人的合作研究成果,重点从冰川水文、冻土水文和区域水文变化三方面总结了其对寒区水文学发展所做的创新与贡献.文章列出了每项研究成果的核心内容,并给予了简要评述.所选成果中,冰川水文方面研究涉及冰川对河川径流的调节作用、冰川径流对气候变化的响应机理等;冻土水文研究着重介绍了多年冻土变化对流域径流过程及其变化影响方面的系统性成果;区域水文变化研究方面,选取了降水观测误差修正、气候变化对区域径流的影响等方面的创新成果.这些研究成果极大地提高了我国在世界寒区水文学研究的地位,对认识寒区水文过程及气候变化对水资源的影响具有重要科学意义. 展开更多
关键词 冰川水文 冻土水文 区域水文变化 气候变化 创新与贡献 叶柏生研究员
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引领工程教育创新发展 培养一流工程科技人才 被引量:16
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作者 张满 乔伟峰 王孙禺 《高等工程教育研究》 CSSCI 北大核心 2019年第2期117-123,共7页
2018年9月24~25日,清华大学、中国工程院和联合国教科文组织共同举办了第一届国际工程教育论坛。论坛围绕全球化背景下工程教育面临的机遇与挑战、工程教育的实践与探索、一流工科建设、工程教育的创新发展、工程教育的可持续发展等问... 2018年9月24~25日,清华大学、中国工程院和联合国教科文组织共同举办了第一届国际工程教育论坛。论坛围绕全球化背景下工程教育面临的机遇与挑战、工程教育的实践与探索、一流工科建设、工程教育的创新发展、工程教育的可持续发展等问题进行了交流和讨论,来自全球不同领域的专家提出了各自的见解。近200位代表参加了本次论坛,论坛上共有来自中国、美国、德国、日本、英国、瑞典、加拿大、新加坡等国的68位知名大学校长、专家学者、研究机构和企业代表进行了发言。本文基于这些发言从工程教育面临的主要挑战、工程教育的创新实践和未来工程人才培养与工程教育发展趋势三个方面提出了相关观点。 展开更多
关键词 工程教育 创新发展 一流工科建设 可持续发展
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Association between hepatitis B and metabolic syndrome:Current state of the art 被引量:9
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作者 Peter Jarcuska Sylvia Drazilova +2 位作者 Jan Fedacko Daniel Pella Martin Janicko 《World Journal of Gastroenterology》 SCIE CAS 2016年第1期155-164,共10页
Chronic hepatitis B(CHB)is a global health issue that increases the risk of liver cirrhosis and hepatocellular carcinoma in infected patients.Metabolic syndrome(Met S)is a disease endemic mostly to the developed count... Chronic hepatitis B(CHB)is a global health issue that increases the risk of liver cirrhosis and hepatocellular carcinoma in infected patients.Metabolic syndrome(Met S)is a disease endemic mostly to the developed countries.It is associated with high cardiovascular mortality and morbidity,diabetes mellitus as well as cancer.In this manuscript,we systematically review the published data on the relationship between Met S and CHB infection.Multiple studies have described highly variable correlations between CHB on one hand and Met S,non-alcoholic fatty liver disease and dyslipidemia on the other.No association between CHB and diabetes mellitus or atherosclerosis has been described as of now.The presence of Met S in patients infected with hepatitis B virus increases the risk of fibrosis,cirrhosis and hepatocellular carcinoma.Appropriate lifestyle,but also pharmacological interventions are needed to prevent the development of these complications. 展开更多
关键词 HEPATITIS B NONALCOHOLIC FATTY liver disease FIBROSIS CIRRHOSIS Metabolic syndrome Hepatocellularcarcinoma
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Neuroprotective agents effective against radiation damage of central nervous system 被引量:5
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作者 Mária Lalkovičová 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第9期1885-1892,共8页
Ionizing radiation caused by medical treatments,nuclear events or even space flights can irreversibly damage structure and function of brain cells.That can result in serious brain damage,with memory and behavior disor... Ionizing radiation caused by medical treatments,nuclear events or even space flights can irreversibly damage structure and function of brain cells.That can result in serious brain damage,with memory and behavior disorders,or even fatal oncologic or neurodegenerative illnesses.Currently used treatments and drugs are mostly targeting biochemical processes of cell apoptosis,radiation toxicity,neuroinflammation,and conditions such as cognitive-behavioral disturbances or others that result from the radiation insult.With most drugs,the side effects and potential toxicity are also to be considered.Therefore,many agents have not been approved for clinical use yet.In this review,we focus on the latest and most effective agents that have been used in animal and also in the human research,and clinical treatments.They could have the potential therapeutical use in cases of radiation damage of central nervous system,and also in prevention considering their radioprotecting effect of nervous tissue. 展开更多
关键词 antioxidants biomedical neuroprotectants central nervous system ionizing radiation NEUROPROTECTION radiation injury radiomitigators radioprotectants RADIOPROTECTION THERAPEUTICS
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