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多焦点多光子显微成像经典数据压缩应用研究

杭州电子科技大学学报（自然科学版） 2010年第4期30卷 40-44页

作者：王瑞荣何峰丁颖金朝阳王建中薛安克 peter tc so 杭州电子科技大学自动化学院浙江杭州310018 麻省理工学院机械工程系马赛诸萨州02139

该文针对多焦点多光子显微镜被越来越多地用于生物组织的三维成像。由于三维成像的实时图像数据巨大,开发实时压缩算法将有助于大规模图像数据的采集和存储。基于霍夫曼编码的无损压缩算法和基于离散余弦变换的JPEG有损压缩算法,对多焦... 详细信息

该文针对多焦点多光子显微镜被越来越多地用于生物组织的三维成像。由于三维成像的实时图像数据巨大,开发实时压缩算法将有助于大规模图像数据的采集和存储。基于霍夫曼编码的无损压缩算法和基于离散余弦变换的JPEG有损压缩算法,对多焦点多光子显微镜成像数据的压缩进行初步研究。实验结果表明,基于霍夫曼编码的无损压缩算法压缩率稍低,但无图像信息丢失;基于JPEG编码的有损压缩算法具有较高的压缩率,但是图像信息会有一定程度的丢失。

关键词：多焦点多光子显微镜霍夫曼编码无损压缩有损压缩

Wear-resistant CoCrNi multi-principal element alloy at cryogenic temperature

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Science Bulletin 2024年第2期69卷 227-236页

作者： Yue Ren Qing Zhou Dongpeng Hua Zhuobin Huang Yulong Li Qian Jia peter Gumbsch Christian Greiner Haifeng Wang Weimin Liu State Key Laboratory of solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Institute for Applied Materials Karlsruhe Institute of TechnologyKarlsruhe 76131Germany IAM-ZM MicroTribology Centerμtc Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Fraunhofer IWM Freiburg 79108Germany State Key Laboratory of solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic temperature.Here,we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K,surpassing those of cryogenic austenitic steels.The temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic simulation.It is found that sliding-induced subsurface structures show distinct scenarios at different deformation temperatures.At cryogenic condition,significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface,which can accommodate massive sliding deformation,in direct contrast to the strain localization and delamination at 273 K.Meanwhile,the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation)also provide additional strengthening and toughening of the subsurface material.These features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

关键词： Multi-principal element alloy Cryogenic temperature Wear CoCrNi

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低温耐磨的CoCrNi多主元合金（英文）

Science Bulletin 2024年第2期 227-236页

作者：任越周青华东鹏黄卓斌李钰龙贾茜 peter Gumbsch Christian Greiner 王海丰刘维民 State Key Laboratory of solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University Institute for Applied Materials Karlsruhe Institute of Technology IAM-ZM Micro Tribology Center μtc Karlsruhe Institute of Technology Fraunhofer IWM State Key Laboratory of solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic temperature. Here, we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K, surpassing those of cryogenic austenitic steels. The temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic simulation. It is found that sliding-induced subsurface structures show distinct scenarios at different deformation temperatures. At cryogenic condition, significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface, which can accommodate massive sliding deformation, in direct contrast to the strain localization and delamination at 273 K.Meanwhile, the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation) also provide additional strengthening and toughening of the subsurface material. These features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

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医用tc4钛合金激光-化学复合抛光及表面形貌演化

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中国表面工程 2024年第2期37卷 227-237页

作者：邵勇孙树峰王萍萍蒙卡·彼得·帕沃尔陈博文张丰云王茜孙维丽青岛理工大学机械与汽车工程学院青岛266520 青岛理工大学信息与控制工程学院青岛266520 斯洛伐克科希策技术大学制造技术学院普雷绍夫08001 青岛黄海学院智能制造学院青岛266427

表面粗糙度是医疗器械构件最重要的质量特征之一,然而现有的激光抛光、化学抛光等单一表面抛光技术存在一定局限性。针对医用tc4钛合金表面的精密抛光需求,设计并搭建一套激光-化学复合抛光系统,通过激光-化学复合加工材料去除机理分析... 详细信息

表面粗糙度是医疗器械构件最重要的质量特征之一,然而现有的激光抛光、化学抛光等单一表面抛光技术存在一定局限性。针对医用tc4钛合金表面的精密抛光需求,设计并搭建一套激光-化学复合抛光系统,通过激光-化学复合加工材料去除机理分析和开展tc4钛合金的激光-化学复合抛光试验,深入探究复合抛光过程中不同抛光阶段材料表面形貌的演变过程及粗糙度变化并进行分析,进而明确激光-化学复合抛光机理。研究结果表明,激光-化学复合抛光材料去除是基于激光热-力效应与激光诱导化学腐蚀溶解共同作用的结果,而且两者具有一定协同效应,在适当的工艺窗口内,化学腐蚀溶解可以完全去除激光烧蚀产生的残渣和重熔物。激光辐照会在工件表面“峰-谷”区域产生温度差,进而导致化学溶解速率差异,即“山峰”区域溶解速率快,“山谷”区域溶解速率慢,从而实现表面粗糙度的降低。最后采用合适的工艺参数,优化了抛光效果,实现了医用tc4钛合金的选择性精密抛光,激光辐照区域表面粗糙度Ra由初始的5.230μm下降至0.225μm,Sa由初始的8.630μm下降至0.571μm,分别下降95.7%和93.4%。研究结果可为钛合金或其他自钝化金属的精密抛光提供参考。

关键词：激光钛合金抛光表面形貌化学腐蚀

Open Science and Data Science

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Data Intelligence 2021年第1期3卷 95-105页

作者： peter Wittenburg Max Planck Computing and Data Facility Gießenbachstraße 285748 GarchingGermany

Data Science(DS)as defined by Jim Gray is an emerging paradigm in all research areas to help finding non-obvious patterns of relevance in large distributed data collections.“Open Science by Design”(OSD),i.e.,making artefacts such as data,metadata,models,and algorithms available and re-usable to peers and beyond as early as possible,is a pre-requisite for a flourishing DS landscape.However,a few major aspects can be identified hampering a fast transition:(1)The classical“Open Science by Publication”(OSP)is not sufficient any longer since it serves different functions,leads to non-acceptable delays and is associated with high curation costs.Changing data lab practices towards OSD requires more fundamental changes than OSP.(2)The classical publication-oriented models for metrics,mainly informed by citations,will not work anymore since the roles of contributors are more difficult to assess and will often change,i.e.,other ways for assigning incentives and recognition need to be found.(3)The huge investments in developing DS skills and capacities by some global companies and strong countries is leading to imbalances and fears by different stakeholders hampering the acceptance of Open Science(OS).(4)Finally,OSD will depend on the availability of a global infrastructure fostering an integrated and interoperable data domain-“one data-domain”as George Strawn calls it-which is still not visible due to differences about the technological key pillars.OS therefore is a need for DS,but it will take much more time to implement it than we may have expected.

关键词： Open Science by Design Open Science by Publication Data Science Data infrastructure Digital Objects FAIR

Global Reference Grids for Big Earth Data

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Big Earth Data 2022年第3期6卷 251-255页

作者： Robert G.Gibb Matthew B.J.Purss Zoheir Sabeur peter Strobl Tengteng Qu Manaaki Whenua–Landcare Research Palmerston NorthNew Zealand Pangaea Innovations Pty.Ltd CanberraAustralia Department of Computing and Informatics Talbot CampusUniversity of BournemouthBournemouthUK European Commission Joint Research Centre(JRC)IspraItaly College of Engineering Peking UniversityBeijingChina

The emerging field of Discrete Global Grid Systems(DGGS)provides a way to organise,store and analyse spatio-temporal data at multiple resolutions and scales(from near global scales down to microns).DGGS partition the entire planet into a discrete hierarchy of global tessellations of progressively finer resolution zones(or cells).Data integration,decomposition and aggregation are optimised by assigning a unique spatio-temporal identifier to each zone.These identifiers are encodings of both the zone’s location and its resolution.As a result,complex multi-dimensional,multi-resolution spatio-temporal operations are simplified into sets of 1D array and filter operations.

关键词： operations simplified partition

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Editors’Note

Data Intelligence 2021年第1期3卷 1-4页

作者： peter Wittenburg George Strawn Max Planck Computing and Data Facility Gießenbachstraße 285748 GarchingGermany US National Academy of Sciences Washington DC 20418USA

In 2019 the German Leibniz research organization sponsored a conference on Open Science(OS)with the idea to publish some of the presented papers in the Data Intelligence journal.Becoming engaged as editors,we recognized that the term“Open Science”was coined about 10 years ago with the intention as pointed out by Michael Nielson:“OS is the idea that scientific knowledge of all kinds should be openly shared as early as is practical in the discovery process”.

关键词： pointed Open journal

Natural forests in New Zealand–a large terrestrial carbon pool in a national state of equilibrium

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Forest Ecosystems 2021年第3期8卷 458-478页

作者： Thomas Paul Mark O.Kimberley peter N.Beets Scion Private Bag 3020Rotorua 3046New Zealand Environmental Statistics Ltd Whangapararoa 0930New Zealand retired(previously Scion) Rotorua 3010New Zealand

Background:Natural forests cover approximately 29%of New Zealand’s landmass and represent a large terrestrial carbon pool.In 2002 New Zealand implemented its first representative plot-based natural forest inventory to assess carbon stocks and stock changes in these mostly undisturbed old-growth forests.Although previous studies have provided estimates of biomass or carbon stocks,these were either not fully representative or lacked data from important pools such as dead wood(coarse woody debris).The current analysis provides the most complete estimates of carbon stocks and stock changes in natural forests in New Zealand.Results:We present estimates of per hectare carbon stocks and stock changes in live and dead organic matter pools excluding soil carbon based on the first two measurement cycles of the New Zealand Natural Forest Inventory carried out from 2002 to 2014.These show that New Zealand’s natural forests are in balance and are neither a carbon source nor a carbon sink.The average total carbon stock was 227.0±14.4 tc·ha^(−1)(95%C.I.)and did not change significantly in the 7.7 years between measurements with the net annual change estimated to be 0.03±0.18 tc·ha^(−1)·yr^(−1).There was a wide variation in carbon stocks between forest groups.Regenerating forest had an averaged carbon stock of only 53.6±9.4 tc·ha^(−1) but had a significant sequestration rate of 0.63±0.25 tc·ha^(−1)·yr^(−1),while tall forest had an average carbon stock of 252.4±15.5 tc·ha^(−1),but its sequestration rate did not differ significantly from zero(−0.06±0.20 tc·ha^(−1)·yr^(−1)).The forest alliance with the largest average carbon stock in above and below ground live and dead organic matter pools was silver beech-red beech-kamahi forest carrying 360.5±34.6 tc·ha^(−1).Dead wood and litter comprised 27%of the total carbon stock.Conclusions:New Zealand’s Natural Forest Inventory provides estimates of carbon stocks including estimates for difficult to measure pools such as dead wood and roots.It also provides estimates of uncertainties inclu

关键词： Forest inventory Natural forests Carbon stocks and change Terrestrial carbon pool

Not Ready for Convergence in Data Infrastructures

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Data Intelligence 2021年第1期3卷 116-135页

作者： Keith Jeffery peter Wittenburg Larry Lannom George Strawn Claudia Biniossek Dirk Betz Christophe Blanchi Keith G Jeffery Consultants 71 Gilligans WayFaringdon SN77FXUK Max Planck Computing and Data Facility Gießenbachstraße 285748 GarchingGermany Corporation for National Research Initiatives(CNRI) RestonVirginia 20191USA US National Academy of Sciences Washington DC 20418USA GESIS-Leibniz Institute for the social Sciences Unter Sachsenhausen 6-850667CologneGermany Corporation for National Research Initiatives RestonVirginia 20191USA

Much research is dependent on Information and Communication Technologies(ICT).Researchers in different research domains have set up their own ICT systems(data labs)to support their research,from data collection(observation,experiment,simulation)through analysis(analytics,visualisation)to publication.However,too frequently the Digital Objects(DOs)upon which the research results are based are not curated and thus neither available for reproduction of the research nor utilization for other(e.g.,multidisciplinary)research purposes.The key to curation is rich metadata recording not only a description of the DO and the conditions of its use but also the provenance-the trail of actions performed on the DO along the research workflow.There are increasing real-world requirements for multidisciplinary research.With DOs in domain-specific ICT systems(silos),commonly with inadequate metadata,such research is hindered.Despite wide agreement on principles for achieving FAIR(findable,accessible,interoperable,and reusable)utilization of research data,current practices fall short.FAIR DOs offer a way forward.The paradoxes,barriers and possible solutions are examined.The key is persuading the researcher to adopt best practices which implies decreasing the cost(easy to use autonomic tools)and increasing the benefit(incentives such as acknowledgement and citation)while maintaining researcher independence and flexibility.

关键词： Scientific process Workflow Metadata FAIR Scientific data Data wrangling