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Geoscience Frontiers 2020年第5期11卷 1889-1894页

作者： steffen H.Buttner Department of Geology Rhodes University6139Makhanda(Grahamstown)South Africa

In their recent publication Van Schijndel et al.(2020) present new age data and P-T analysis from the eastern margin of the Namaqua Sector of the Namaqua Natal Metamorphic *** authors claim to provide evidence for the... 详细信息

关键词： Province. burial eastern

基于LiDAR点云的中国传统园林视觉空间定量分析方法——以寄畅园为例

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风景园林 2024年第7期31卷 108-114页

作者：张冠亭彭予洋 [荷]史蒂芬·奈豪斯南京工业大学建筑学院代尔夫特理工大学建筑与建成环境学院代尔夫特理工大学景观部门

【目的】中国传统园林空间复杂多变,传统的分析方法难以深入探索传统园林复杂的三维视觉空间特征。三维激光雷达(light detection and ranging,LiDAR)点云技术在传统园林空间研究方面具有精度高、信息全等优势,借助LiDAR点云技术深入探... 详细信息

【目的】中国传统园林空间复杂多变,传统的分析方法难以深入探索传统园林复杂的三维视觉空间特征。三维激光雷达(light detection and ranging,LiDAR)点云技术在传统园林空间研究方面具有精度高、信息全等优势,借助LiDAR点云技术深入探索中国传统园林视觉空间特征,可为现代人居环境空间营造提供借鉴与参考。【方法】基于LiDAR点云技术提出一套适用于中国传统园林视觉空间分析的方法,并以三维可视性、视野舒展度及景物视野占比3项指标量化描述视觉空间。【结果】以寄畅园为例,构建了寄畅园LiDAR点云体素模型,利用提出的方法对锦汇漪西侧滨水步道11个视点的视觉空间进行了量化分析,解析了寄畅园的视觉空间特征,并探究了该步道的空间感知序列。【结论】证实了利用LiDAR点云技术展开传统园林视觉空间研究的可行性与准确性,提出的方法可应用于其他传统园林视觉空间的分析研究中。

关键词：中国传统园林 LiDAR点云空间视觉感知景观视觉特征视觉量化指标

Nutrient retention and release in coarse woody debris of three important central European tree species and the use of NIRS to determine deadwood chemical properties

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Forest Ecosystems 2018年第3期5卷 296-310页

作者： steffen Herrmann Jurgen Bauhus Faculty of Environment and Natural Resources University of Freiburg Tennenbacherstr.4D-79106Freiburg i.Br.Germany Thunen Institute of Forest Ecosystems Alfred-M611er-Strabe 1Haus41/4216225EberswaldeGermany

Background: Coarse woody debris(CWD) is very important for forest ecosystems, particularly for biodiversity and carbon storage. Its relevance as a possible reservoir and source of nutrients is less clear, especially in central ***: Based on a chronosequence of known ages of logs, we analyzed the nutrients stored in CWD of Fagus sylvatica, Picea abies, and Pinus sylvestris at different sites in Germany. To quantify nutrient concentrations, we assessed the use of Near Infrared Reflectance Spectroscopy(NIRS) to determine the chemical properties of ***: NIRS models were suitable to predict concentrations of C, N, P, lignin and extractives. Concentrations of most nutrients increased with mass loss, with the exception of potassium, which decreased for beech and pine and remained relatively constant for spruce. The highest nutrient concentrations(N, P, S, Ca and Mn, except Mg and K) were generally observed in highly decomposed spruce logs. The net effect of decreasing CWD mass and increasing nutrient concentrations was either a decreasing(N, P and K in beech; P, Mg, K and Mn in pine), constant(S, Ca and Mg in beech; N, S and Ca in pine) or increasing amount of nutrients(N, P, S and Ca in spruce; Mn in beech) in the logsover the course of decomposition. The C/N ratio decreased for all tree species, most markedly for spruce from ca. 1000 at the beginning of the decomposition process to 180 at 36 years. The N/P ratio converged to a value of about 30 forall three species. Lignin concentrations increased for spruce and beech and remained constant for ***: Our results indicate that most nutrients remain in CWD for long periods. Nutrients may be used and cycled by microorganisms within CWD, but with the exception of P(in beech), Mg(in pine) and K(in beech and pine), there appears to be little net nutrient export until two thirds of the mass is lost. Instead, N, P, S and Ca were accumulated in spruce logs, indicating that CWD became a net sink rathe

关键词： CWD NIRS Decay Carbon F.sylvatica P.abies P.sylvestris

Separating polydisperse particles using electrostatic precipitators with wire and spiked-wire discharge electrode design

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Particuology 2018年第3期16卷 10-17页

作者： Soren Sander steffen Gawor Udo Fritsching Process Engineering Stiftung Institut ffir Werlcstofftechnik Badgasteiner Strasse 3 28359 Bremen Germany Particles and Process Engineering University of Bremen Bibliothekstrasse 1 28359 Bremen. Germany

Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the flow structure of particles through ionic winds and mean electric fields are revealed. Numeri- cal studies throughout the past years have shown these structures for channel and pipe configurations. However, less attention was given to field averaging for the ni,~r-product and electric field. Our study focuses on this averaging and illustrates relevant differences between multidimensional setups concern- ~ng these fields. Turbulence was modeled using the Reynolds-averaged Navier-Stokes equations with a second-order Reynolds-stress-model closure. A high three-dimensionality of the ionic wind-induced turbulence is presented. This leads to an increase in the submicron-particle precipitation rate. The results confirm the dependence of separation efficiency on particle density and permittivity, thereby showing the advantages of spiked wires compared with wire-plate setups used in electrostatic precipitators.

关键词： Electro-hydrodynamic CFD simulation Electrostatic particle precipitation Electrode design Collection efficiency

Rac GTPases:domain-specific functions in neuronal development

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Neural Regeneration Research 2019年第8期14卷 1367-1368页

作者： steffen Norgaard Roger Pocock Development and Stem Cells Program Monash Biomedicine Discovery Institute and Department of Anatomy and Developmental Biology Monash University Melbourne Victoria Australia Biotech Research and Innovation Centre University of Copenhagen Copenhagen Denmark

Understanding fundamental mechanisms governing axon outgrowth and guidance can inform the development of therapeutic strategies to restore neuronal function damaged though injury or disease. Axons navigate the extracellular environment by responding to guidance cues that bind to cell surface receptors to relay information intracellularly via Rho GTPase family members, including the Rac GTPases.

关键词： Rac GTPases domain-specific functions neuronal development

A laminated tufa carbonate from the mid Holocene of the Qilian Mountains and its potential for palaeoclimate inferences

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Episodes 2008年第4期31卷 401-407页

作者： steffen Mischke Chengjun Zhang Institute of Geological Sciences Freie Universitat Berlin Malteserstr. 74-100 12249 Berlin Germany Lanzhou University Centre for Arid Environment and Paleoclimate Research Gansu 730000 China

A mid-Holocene tufa section at 3,815 m altitude in the Qilian Mountains at the northeastern margin of the Tibetan Plateau was tested as a possibly important new climate archive. The tufa carbonate displays a distinct alternation of white and dark layers most probably representing annually deposited sparry and microgranular calcite which is formed during the warm and relatively wet summer and the drier and cooler spring and autumn season with an interruption of tufa formation during the freezing period. The δ^18O record of the tufa site comprises probably 357 years of annually deposited car-bonate-about 4, 000 years bejCore present, which indicates the prevalence of wetter climatic con- ditions in comparison to the present-day situation. This inference is confirmed by palynological data and lake-level reconstructions from a number of sites in the northern foreland of the Qilian Mountains, highlighting the large potential of longer tufa sequences for high-resolution palaeoclimate studies in the future.

关键词：祁连山全新世中期片状石灰华碳酸盐

Carbon and Oxygen Isotopic Composition of Surface-Sediment Carbonate in Bosten Lake (Xinjiang,China) and its Controlling Factors

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 386-395页

作者： steffen MISCHKE Alexander PROKOPENKO Freie University Berlin BerlinGermany Department of Geological Sciences University of South CarolinaColumbiaSouth CarolinaUSA

Bosten Lake is a mid-latitude lake with water mainly supplied by melting ice and snow in the Tianshan Mountains. The depositional environment of the lake is spatially not uniform due to the proximity of the major inlet and the single outlet in the western part of the lake. The analytical results show that the carbon and oxygen isotopic composition of recent lake sediments is related to this specific lacustrine depositional environment and to the resulting carbonate mineralogy. In the southwestern lake region between the Kaidu River inlet and the Kongqi River outlet, carbon isotope composition （δ^13C） values of the carbonate sediment （-1‰ to -2‰） have no relation to the oxygen isotope composition of the carbonate （δ^18O） values （-7‰ to -8‰）, with both isotopes showing a low variability. The carbonate content is low （〈20%）. Carbonate minerals analyzed by X-ray diffraction are mainly composed of calcite, while aragonite was not recorded. The salinity of the lake water is low in the estuary region as a result of the Kaidu River inflow. In comparison, the carbon and oxygen isotope values are higher in the middle and eastern parts of the lake, with δ^13C values between approximately ＋0.5‰ and ＋3‰, and δ^18O values between -1‰ and -5‰. There is a moderate correlation between the stable oxygen and carbon isotopes, with a coefficient of correlation r of approximately 0.63. This implies that the lake water has a relatively short residence time. Carbonate minerals constitute calcite and aragonite in the middle and eastern region of the lake. Aragonite and Mg-calcite are formed at higher lake water salinity and temperatures, and larger evaporation effects. More saline lake water in the middle and eastern region of the lake and the enhanced isotopic equilibrium between water and atmospheric CO2 cause the correlating carbon and oxygen isotope values determined for aragonite and Mg-calcite. Evaporation and biological processes are the main reasons for the salinity and carbonate mi

关键词： carbonate aragonite calcite stable carbon and oxygen isotope composition Bosten Lake

Challenges in the conduct of randomised controlled trials in cardiogenic shock complicating acute myocardial infarction

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Journal of Geriatric Cardiology 2022年第2期19卷 125-129页

作者： Anne Freund steffen Desch Holger Thiele Department of Internal Medicine/Cardiology Heart Center Leipzig at the University of LeipzigLeipzigGermany German Center for Cardiovascular Research(DZHK) BerlinDeutschland

Cardiogenic shock(CS)following acute myocardial infarction(AMI)is a major challenge in cardiovascular *** remains high with 40%-50%after thirty *** controlled trials(RCTs)play a key role to generate evidence on optimal care in this ***,the number of completed or ongoing RCTs is still relatively low compared to the gaps in *** in the conduct of these trials are in particular the selection of patients and ethical issues in the informed consent *** determining eligibility criteria,special attention should be paid to the severity of CS,to the inclusion of patients with cardiac arrest and to potential age *** age of AMI-CS patients is *** limits are therefore controversial as it is important to include elderly patients in RCTs in order to make the results generalisable and to address the special needs of this *** patients with AMI-CS are in most cases unable to provide informed consent themselves,a step-wise approach with acute consent by a legal representative or independent physicians and later informed consent by the patient if possible might be established depending on regularities of the respective ethical review board and country *** studies should be sought to generate adequate power.

关键词： shock legal consent

KGI-XGIS SUPPORTING DECISION MAKING WITH KNOWLEDGE-BASED TECHNIQUES

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Geo-Spatial Information Science 2001年第2期4卷 40-46页

作者： steffen Vogt Dcandidate Department of Physical Geography University of Freiburg

The concept of the King George Island Expert GIS (KGI_XGIS) is ***_XGIS is a combination of a rule_based expert system and a GIS meant to form an intelligent spatial decision support *** system provides the spatial knowledge necessary for the environmental impact assessment process as dictated by the ’Madrid Protocol’ for King George Island (South Shetland Islands,Antarctica).It also serves as information system to the scientific user *** maps,remote sensing data,thematic maps based on field surveys and other digital data form the input data to the *** the sparseness of the available data these must be combined and used in the most efficient *** expert knowledge of different domains will be coded into a rule_based expert system which is coupled to the *** handle the expert knowledge and the spatial data of different types and different quality the KGI_XGIS incorporates knowledge_based techniques and fuzzy *** selection of a camp site on the ice free area of Fildes Peninsula and data quality management are used as two examples to demonstrate the capabilities of the system.

关键词： KGI-XGIS spatial data EIA process expert system

健康蓝色空间设计:将接触感知蓝色空间的健康效益转化为设计实践的方法论框架

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风景园林 2024年第7期31卷 39-47页

作者：张皓翔 [荷]史蒂芬·奈豪斯 [比]卡洛琳·牛顿代尔夫特理工大学建筑与建成环境学院代尔夫特理工大学景观部门代尔夫特理工大学空间规划与策略部门

【目的】水是人类赖以生存和发展的关键要素。以水为核心的蓝色空间一直以来不断塑造着城市,提供了多样化的生态系统服务。越来越多的证据表明接触感知蓝色空间能够为城市居民带来显著的健康效益。因此,在响应健康城市建设及可持续发展... 详细信息

【目的】水是人类赖以生存和发展的关键要素。以水为核心的蓝色空间一直以来不断塑造着城市,提供了多样化的生态系统服务。越来越多的证据表明接触感知蓝色空间能够为城市居民带来显著的健康效益。因此,在响应健康城市建设及可持续发展目标的背景下,有必要探讨将接触感知蓝色空间产生的健康效益纳入空间设计实践的可能性。【方法】基于对核心文献的检索和筛选,系统梳理接触感知蓝色空间以促进人类健康的主要路径,提出将健康证据转译为设计实践的方法论框架。【结果】基于3种蓝色空间接触感知类型,归纳出4条联系蓝色空间接触感知和公共健康的主要路径:1)促进体力活动;2)降低有害暴露;3)提供心理效益;4)鼓励社会交往。提出了一个将健康证据转译为设计知识的四步方法论框架并结合已有证据和案例进行说明:1)收集主要健康证据;2)提炼关键设计概念;3)划分核心设计要素;4)转译设计原则、空间模式、评估方法。【结论】根据“分析—综合—评估”设计范式,探讨了从健康证据转化出的设计知识在设计迭代中的应用潜力,反思了方法论框架的双向互动优势,指出实践能够作为启发设计知识和提供健康证据的工具。

关键词：风景园林蓝色空间接触感知健康效益证据转译空间设计数字工具