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Robust Filtration Techniques in Geometrical Metrology and Their Comparison

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International journal of Automation and computing 2013年第1期10卷 1-8页

作者： Shan Lou wen-Han Zeng Xiang-Qian jiang Paul j. Scott EPSRC Centre for Innovative Manufacturing in Advanced Metrology University of Huddersfield

Filtration is one of the core elements of analysis tools in geometrical metrology. Filtration techniques are progressing along with the advancement of manufacturing technology. Modern filtration techniques are required to be robust against outliers, applicable to surfaces with complex geometry and reliable in whole range of measurement data. A comparison study is conducted to evaluate commonly used robust filtration techniques in the field of geometrical metrology, including the two-stage Gaussian filter, the robust Gaussian regression filter, the robust spline filter and morphological filters. They are compared in terms of four aspects： functionality, mathematical computation, capability and characterization parameters. As a result, this study offers metrologists a guideline to choose the appropriate filter for various applications.

关键词： Geometrical metrology robust Gaussian regression filter robust spline filter morphological filters surface roughness

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玉米秸秆对风沙土土壤微生物的影响

内蒙古林业科技 2019年第1期45卷 5-10页

作者：袁立敏张文军闫德仁黄海广刘博内蒙古自治区林业科学研究院内蒙古呼和浩特010010 内蒙古自治区森林资源资产评估管理中心内蒙古呼和浩特010010

本研究以新型沙袋沙障为研究对象,分别对不同内部添加物、不同外层材料袋沙障内部、外部风沙土土壤细菌、真菌、放线菌及土壤微生物总量进行了测定。结果表明:沙袋沙障内添加玉米秸秆、玉米芯营养物质能够有效改善沙袋沙障内部风沙土环... 详细信息

本研究以新型沙袋沙障为研究对象,分别对不同内部添加物、不同外层材料袋沙障内部、外部风沙土土壤细菌、真菌、放线菌及土壤微生物总量进行了测定。结果表明:沙袋沙障内添加玉米秸秆、玉米芯营养物质能够有效改善沙袋沙障内部风沙土环境,沙障内部微生物数量显著提高,微生物总数量分别达到了7.35×10~7 cfu/g、9.47×10~7 cfu/g,分别是对照(只灌装风沙土)沙袋沙障的113.11倍、145.62倍,并且添加玉米芯的作用效果更加显著,土壤微生物总数比添加玉米秸秆的高28.77%;添加玉米秸秆、玉米芯均对土壤真菌的影响较大,真菌数量可升高至微生物总数量的50%以上;玉米秸秆、玉米芯添加量越多,微生物数量越多,添加物体积百分比达到20%时,土壤微生物总数达到了1.01×10~8 cfu/g,随着添加量的继续增加,沙障内微生物数量无显著增加趋势;3种外层材料黄麻纤维、玻璃纤维、稻草沙袋沙障内部微生物总数排序为黄麻纤维>稻草>玻璃纤维,黄麻纤维沙障内部土壤细菌、真菌、放线菌三者总数分别比稻草、玻璃纤维的高58.80%、112.64%。

关键词：沙袋沙障外层材料填充物细菌真菌放线菌库布齐沙漠

Lipid droplet dynamics in alcoholic fatty liver disease

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Liver Research 2019年第3期3卷 185-190页

作者： Ryan j.Schulze wen-Xing Ding Department of Biochemistry and Molecular Biology and the Division of Gastroenterology and Hepatology Mayo ClinicRochesterMNUSA Department of Pharmacology Toxicologyand TherapeuticsThe University of Kansas Medical CenterKansas CityKSUSA

The rising incidence of alcohol-related liver disease(ALD)demands making urgent progress in understanding the fundamental molecular basis of alcohol-related hepatocellular *** of the key early events accompanying chronic alcohol usage is the accumulation of lipid droplets(LDs)in the hepatocellular *** are far from inert sites of neutral lipid storage;rather,they represent key organelles that play vital roles in the metabolic state of the *** this review,we will examine the biology of these structures and outline recent efforts being made to understand the effects of alcohol exposure on the biogenesis,catabolism,and motility of LDs and how their dynamic nature is perturbed in the context of ALD.

关键词： Lipid droplet(LD) Alcohol Autophagy Lipolysis Hepatocyte Steatosis

云南省城市土地利用效率与土地生态安全耦合协调研究

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国土与自然资源研究 2025年第1期 1-7页

作者：温婷杨诗琴云南财经大学国土资源与持续发展研究所云南昆明650221

为深入探究城市土地利用效率与土地生态安全之间的关系,探索出一条既能实现土地高效合理利用又能保护土地生态安全的可持续发展之路。以云南省为例,在构建城市土地利用效率及土地生态安全相应指标体系的基础上,综合运用SBM-Undesirable... 详细信息

为深入探究城市土地利用效率与土地生态安全之间的关系,探索出一条既能实现土地高效合理利用又能保护土地生态安全的可持续发展之路。以云南省为例,在构建城市土地利用效率及土地生态安全相应指标体系的基础上,综合运用SBM-Undesirable模型、综合指数法及耦合协调度模型测算云南省城市土地利用效率与土地生态安全水平及两者的耦合协调度及其时空变化特征。结果表明,(1)2006-2021年云南省城市土地利用效率呈现波动上升的变化趋势,研究期间均值为0.92,总体状况较好。(2)2006-2021年云南省城市土地生态安全水平总体呈现上升趋势,经历了“不安全-较不安全-临界安全-较安全”四个阶段,由2006年的0.18提升至2021年的0.77,土地生态安全水平显著提升。(3)2006-2021年,云南省城市土地利用效率与土地生态安全耦合协调度呈现波动上升的趋势,经历“轻度失调-初步协调-中级协调-良好协调-优质协调”5个阶段,空间格局上呈现西北、中部高,西南、东部地区较低的特征。总体来看,研究期间云南省大部分地区城市土地利用效率与土地生态安全处于协调阶段。

关键词：城市土地利用效率城市土地生态安全耦合协调

Deep potentials for materials science

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Materials Futures 2022年第2期1卷 89-115页

作者： Tongqi wen Linfeng Zhang Han Wang Weinan E David j Srolovitz Department of Mechanical Engineering The University of Hong KongHong KongHong Kong Special Administrative Region of China DP Technology BeijingPeople’s Republic of China AI for Science Institute BeijingPeople’s Republic of China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijingPeople’s Republic of China HEDPS CAPTCollege of EngineeringPeking UniversityBeijingPeople’s Republic of China School of Mathematical Sciences Peking UniversityBeijingPeople’s Republic of China Department of Mathematics and Program in Applied and Computational Mathematics Princeton UniversityPrincetonNJUnited States of America International Digital Economy Academy(IDEA) ShenzhenPeople’s Republic of China

To fill the gap between accurate(and expensive)ab initio calculations and efficient atomistic simulations based on empirical interatomic potentials,a new class of descriptions of atomic interactions has emerged and been widely applied;*** learning potentials(MLPs).One recently developed type of MLP is the deep potential(DP)*** this review,we provide an introduction to DP methods in computational materials *** theory underlying the DP method is presented along with a step-by-step introduction to their development and *** also review materials applications of DPs in a wide range of materials *** DP Library provides a platform for the development of DPs and a database of extant *** discuss the accuracy and efficiency of DPs compared with ab initio methods and empirical potentials.

关键词： deep potential atomistic simulation machine learning potential neural network

基于指数滤波模型的青藏高原根系层土壤水分估算研究

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高原气象 2025年第1期44卷 134-149页

作者：宋雨曦苏建宾文军郑东海成都信息工程大学大气科学学院高原大气与环境四川省重点实验室四川成都610225 中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室国家青藏高原科学数据中心北京100101

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河... 详细信息

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河上游、玛曲)数据,本文系统评估了指数滤波模型在青藏高原不同气候与下垫面区域估算根系层(10 cm/20 cm/40 cm)土壤水分的适用性,探讨了不同环境因素(土壤、气候、植被)对模型特征时长参数T值的影响,最后评估了利用三种方法(各观测网络或青藏高原站点最优T值(Topt)中位数、随机森林模型)获取的区域T值估算青藏高原根系层土壤水分的可靠性。研究发现:(1)随着土壤深度的增加,根系层与表层土壤水分的相关性降低,而其空间异质性增大,导致指数滤波模型的应用精度降低,而模型T值及其空间异质性增大;(2)空间上随着降水量和土壤含水量的增加,根系层与表层土壤水分的相关性增大,而其空间异质性降低,使得指数滤波模型的应用精度上升,而其在区域内不同站点应用精度的差异呈现降低趋势;(3)土壤性质尤其是砂土含量是控制青藏高原区域T值空间分布的主要因素;(4)T值的获取对指数滤波模型在青藏高原的应用精度影响较小,当前常用的区域Topt中位数和随机森林模型均能获取相对合理的区域T值和取得一致且相对准确的模拟结果。本研究的发现有望推动利用指数滤波模型基于卫星表层土壤水分资料准确获取青藏高原根系层土壤水分。

关键词：青藏高原指数滤波模型根系层土壤水分不同气候与下垫面区域

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Isotopic insights on quantitative assessments of interaction of eco-hydrological processes in multi-scale karst watersheds

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International Soil and Water Conservation Research 2024年第1期12卷 156-170页

作者： Zhuo Hao Yang Gao Qingwen Zhang wen wen Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Humanities and Social Sciences Beijing Institute of TechnologyBeijing100081China

The dynamics of hydrological processes and the storage mechanisms of karst water resources are the most important issues in karst *** impact of environmental changes on water quantity,and the evaluation and quantification of eco-hydrological processes remain poorly *** this study,high-frequency continuous monitoring in multi-scale karst watersheds in Southwest China combined the approaches of water isotopes and the hybrid single-particle lagrangian integrated trajectory(HYSPLIT)model to identify the recharge mechanisms between atmospheric vapor,rainfall,surface water,and groundwater,and to reveal the interaction of eco-hydrological *** dominant moisture sources in Puding(PD)County were the Indian Ocean(43-69%)and local moisture(24-33%).Theδ^(18)O and deuterium excess(d-excess)values showed a positive correlation indicating that secondary or sub-cloud evaporation was prominent in the wet *** water line-conditioned excess(lc-excess)indicated that karst water interacted with recent precipitation,groundwater,and evaporation across *** to its specific hydrogeological structure,surface water and rainwater have a higher contribution rate to groundwater *** Chenqi stream replenished the Houzhai River mainly in the form of groundwater,with percentages ranging from 38.1 to 93.5%in the wet season,and 47.8-80.1%in the dry *** the Houzhai outlet,surface water and groundwater interconverted frequently with a percentage of 45.6-49.1%.We believe this is the first systematic study to quantify the supply relationship between water vapor transport,rainfall,surface water and groundwater in the Chinese karst zone,making a significant move forward in the field of karst hydrological processes and improving the efficiency of water resource evaluation and management.

关键词： Stable isotope Moisture sources Water cycle Karst watersheds

Analysis of High Temperature Deformed Structure and Dynamic Precipitation in W9Mo3Cr4V Steel

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journal of Iron and Steel Research International 2001年第1期8卷 41-44页

作者： WANG jing-wen WANG Xiong-wen jiangsu Institute of Petrochemical Technology Anhui Institute of Mechanical and Electrical Engineering Wuhu Vocational Technical Institute

TiAl base alloys have potential usage in aerospace engine for their high specific strength. In order to improve their poor hot workability, a new approach of hot deformation processing was investigated. The starting microstructure of Ti 46 5Al 2 5V 1 0Cr (atom percent, %) alloy is fully lamellar (FL) microstructure. The near gamma (NG) microstructure can be obtained through Nickel microalloying and heat treatment at 1 150 ℃. The isothermal compression tests were conducted on both materials using MTS machine at temperatures of 950 ℃, 1 000 ℃, and 1 050 ℃, and the strain rates of 0 01, 0 1 and 1 s -1 . Compared with the γ TiAl alloy with FL microstructure, the Ni bearing alloy with NG microstructure has better hot workability, such as enlarged hot workable region, decreased flow stresses, more uniform and finer deformed microstructure.

关键词： TiAl base alloys hot workability microstructure

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甘氨酸多晶型的研究进展

化学与生物工程 2014年第11期31卷 1-4页

作者：陈佳星刘文举郭亚军卫宏远河南工业大学化学化工学院河南郑州450001 天津大学化工学院天津300072

综述了近年来甘氨酸各种晶型的制备方法、各晶型的热稳定性、结晶条件对晶型的影响、晶型间的相互转化、结晶新工艺及新晶型等方面的研究。对甘氨酸多晶型的研究,不仅有助于甘氨酸晶型的控制及新晶型的开发,而且可为其它药物晶型的研究... 详细信息

综述了近年来甘氨酸各种晶型的制备方法、各晶型的热稳定性、结晶条件对晶型的影响、晶型间的相互转化、结晶新工艺及新晶型等方面的研究。对甘氨酸多晶型的研究,不仅有助于甘氨酸晶型的控制及新晶型的开发,而且可为其它药物晶型的研究提供新的思路和指导。

关键词：甘氨酸多晶型结晶工艺晶型转变