检索结果-南通市图书馆

On the LSP3 estimates of surface gravity for LAMOST-Kepler stars with asteroseismic measurements

Research in Astronomy and Astrophysics 2016年第3期16卷 81-90页

作者： Juan-Juan Ren Xiao-Wei Liu Mao-Sheng Xiang Yang Huang saskia hekker Chun Wang Hai-Bo Yuan Alberto Rebassa-Mansergas Bing-Qiu Chen Ning-Chen Sun Hua-Wei Zhang Zhi-Ying Huo Wei Zhang Yong Zhang Yong-Hui Hou Yue-Fei Wang Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Max-Planck-Institut fiir Sonnensystemforschung Justus-von-Liebig-Weg 337077 GottingenGermany Stellar Astrophysics Centre Department of Physics and AstronomyAarhus UniversityNy Munkegade 1208000 Aarhus CDenmark Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China

Asteroseismology allows for deriving precise values of the surface gravity of stars. The accurate asteroseismic determinations now available for the large number of stars in the Kepler fields can be used to check and calibrate surface gravities that are currently being obtained spectroscopically for a huge number of stars targeted by large-scale spectroscopic surveys, such as the on-going Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） Galactic survey. The LAMOST spectral surveys have obtained a large number of stellar spectra in the Kepler fields. Stellar atmospheric parameters of those stars have been determined with the LAMOST Stellar Parameter Pipeline at Peking University （LSP3）, by template matching with the MILES empirical spectral library. In the current work, we compare surface gravities yielded by LSP3 with those of two asteroseismic samples-- the largest Kepler asteroseismic sample and the most accurate Kepler asteroseismic sample. We find that LSP3 surface gravities are in good agreement with asteroseismic values of hekker et al., with a dispersion of -0.2 dex. Except for a few cases, asteroseismic surface gravities ofHuber et al. and LSP3 spectroscopic values agree for a wide range of surface gravities. However, some patterns in the differences can be identified upon close inspection. Potential ways to further improve the LSP3 spectroscopic estimation of stellar atmospheric parameters in the near future are briefly discussed. The effects of effective temperature and metallicity on asteroseismic determinations of surface gravities for giant stars are also discussed.

关键词： methods: data analysis -- stars: fundamental parameters -- stars: spectroscopic -- stars general -- stars: oscillations

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Stochastic Model Approach for Optimisation of Lowland River Restoration Works

引用

Journal of Earth Science 2016年第1期27卷 55-67页

作者： saskia van Vuren Huib de Vriend Hermjan Barneveld Section of Hydraulic Engineering Delft University of Technology 2600 AA Delft the Netherlands HKV Consultants Lelystad the Netherlands

Over the course of centuries, river systems have been heavily trained for the purpose of safe discharge of water, sediment and ice, and improves navigation. Traditionally, dikes are used to be reinforced and heightened to protect countries from ever higher flood levels. Other types of solutions than technical engineering solutions, such as measures to increase the flood conveyance capacity（e.g., lowering of groynes and floodplains, setting back dikes） become more popular. These solutions may however increase the river bed dynamics and thus impact negatively navigation, maintenance dredging and flood safety. A variety of numerical models are available to predict the impact of river restoration works on river processes. Often little attention is paid to the assessment of uncertainties. In this paper, we show how we can make uncertainty explicit using a stochastic approach. This approach helps identifying uncertainty sources and assessing their contribution to the overall uncertainty in river processes. The approach gives engineers a better understanding of system behaviour and enables them to intervene with the river system, so as to avoid undesired situations. We illustrate the merits of this stochastic approach for optimising lowland river restoration works in the Rhine in the Netherlands.

关键词： river restoration flood protection dredging navigation stochastic approach Room forthe River program.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probing the intrinsic catalytic activity of carbon nanotubes for the metal-free oxidation of aromatic thiophene compounds in ionic liquids

引用

Journal of Energy Chemistry 2019年第5期28卷 131-137页

作者： Qingqing Gu Yuxiao Ding Zigeng Liu Yangming Lin Robert Schlogl saskia Heumann Dangsheng Su Shenyang National Laboratory for Material Science Institute of Metal ResearchChinese Academy of SciencesWenhua Road 72Shenyang 110016LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-3645470 Millheim a.d.RuhrGermany Fritz Haber Institute of the Max Planck Society Faradayweg 4-614195 BerlinGermany

A metal-free catalytic system combining oxidized carbon nanotubes (oCNTs) and ionic liquids (ILs) is presented for the oxidation of aromatic thiophene compounds with H2O2 as an oxidant. The oCNTs exhibit impressively high activity and stability in the system, which show an even better performance than those of some reported metal catalysts. The ILs are proved to have indispensable influence on the enhanced catalytic performance of the oCNTs. Detailed characterization by TG-MS and XPS demonstrates that the carbonyl groups are the active sites for the oxidation process, which is further supported by the deactivation and the model catalysts experiments. The quantitative analysis of different oxygen groups in oCNTs could be achieved by an isothermal temperature programmed TG-MS method. The concentration of carbonyl groups is 1.46 mmol per 1 g oCNTs and the tuiriover frequency of oCNTs could also be obtained (10.7 h^-1 in the presence of OmimPF6). H2O2 decomposition experiments combined with the EPR results reveal that the presence of OmimPF6 can avoid the intermediate HO· to form O2 and then improve the catalytic performance of oCNTs for the oxidation of dibenzothiophene.

关键词： Carbon nanotubes Metal-free catalysis Oxidative desulfurization Ionic liquids

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nanostructure in energy conversion

引用

Journal of Energy Chemistry 2016年第2期25卷 169-188页

作者： saskia Buller Jennifer Strunk Max-Planck-Institute for Chemical Energy Conversion Mulheim Ruhr Germany Center for Nanointegration Duisburg-Essen University of Duisburg-Essen Germany

Nanostructured and nanosized materials are widely applied to tackle the pressing challenges associated with energy conversion. In this conceptual review, rather than highlighting separate examples, we aim to give a general overview about where and how nanostructure design can be beneficial in the three major research fields（photo）thermal chemical energy conversion, electrochemical energy conversion, and solar energy conversion. It will be shown that in many cases the design of catalytically active nanostructures is the main task and that especially for catalysts nanostructure and activity are inseparably linked to each other. Moreover, electrochemical and photochemical processes are complicated by the overlap of multiple processes that all need to be optimized, including in particular light absorption, charge migration,recombination and trapping events and surface processes. It will also be shown how the development of materials for new challenges can often be based on our knowledge on existing materials for related applications.

关键词： Renewable energy Nanostructure Electrochemical energy Solar power

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of soil management on soil erosion on sloping farmland during crop growth stages under a large-scale rainfall simulation experiment

引用

Journal of Arid Land 2018年第6期10卷 921-931页

作者： WANG Linhua WANG Yafeng Keesstra saskia Cerdà ARTEMI MA Bo WU Faqi State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Soil and Water Conservation Northwest A&F University Civil Surveying and Environmental Engineering The University of Newcastle Soil Physics and Land Management Group Wageningen University Soil Erosion and Degradation Research Group Department of Geography University of Valencia College of Natural Resources and Environment Northwest A&F University

Soil erosion on farmland is a critical environmental issue and the main source of sediment in the Yellow River, China. Thus, great efforts have been made to reduce runoff and soil loss by restoring vegetation on abandoned farmland. However, few studies have investigated runoff and soil loss from sloping farmland during crop growth season. The objective of this study was to investigate the effects of soil management on runoff and soil loss on sloping farmland during crop growth season. We tested different soybean growth stages (i.e., seedling stage (R1), initial blossoming stage (R2), full flowering stage (R3), pod bearing stage (R4), and initial filling stage (R5)) and soil management practice (one plot applied hoeing tillage (HT) before each rainfall event, whereas the other received no treatment (NH)) by applying simulated rainfall at an intensity of 80 mm/h. Results showed that runoff and soil loss both decreased and infiltration amount increased in successive soybean growth stages under both treatments. Compared with NH plot, there was less runoff and higher infiltration amount from HT plot. However, soil loss from HT plot was larger than that from NH plot in R1–R3, but lower in R4 and R5. In the early growth stages, hoeing tillage was effective for reducing runoff and enhancing rainfall infiltration. By contrast, hoeing tillage enhanced soil and water conservation during the late growth stages. The total soil loss from HT plot (509.0 g/m2) was 11.1% higher than that from NH plot (457.9 g/m2) in R1–R5. However, the infiltration amount from HT plot (313.9 mm) was 18.4% higher than that from NH plot (265.0 mm) and the total runoff volume from HT plot was 49.7% less than that from NH plot. These results indicated that crop vegetation can also act as a type of vegetation cover and play an important role on sloping farmland. Thus, adopting rational soil management in crop planting on sloping farmland can effectively reduce runoff and soil loss, as well as maximize ra

关键词： hoeing tillage soil erosion simulated rainfall crop growth stages Loess Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Toward more reliable stability measurements in stance: recommendations for number of measurements, foot position and feedback——a cross-sectional study among servicemen

引用

Military Medical Research 2020年第2期7卷 199-208页

作者： saskia Maria Theresia van der Heijden Maarten Reinders Prins Peter van der Wurff Physical Therapy Sciences Program in Clinical Health SciencesUniversity Medical Center Utrecht3584CX UtrechtThe Netherlands Research and Development Military Rehabilitation Center AardenburgKorte Molenweg 33941PW DoomThe Netherlands Department of Human Movement Sciences Faculty of Behavioural and Movement SciencesVrije Universiteit Amsterdam and Amsterdam Movement Sciences1081BT AmsterdamThe Netherlands Institute for Human Movement Studies HU University of Applied Sciences Utrecht3584CS UtrechtThe Netherlands

Background:In the military,insufficient postural stability is a risk factor for developing lower extremity *** stability training programs are effective in preventing these ***,an objective method for the measurement of postural stability in servicemen is *** primary objective of this study was to assess the influence of the number of repetitions,different foot positions and real-time visual feedback on postural stability,as well as their effects on the intrasession reliability of postural stability measurements in *** secondary objective was to assess the concurrent validity of the ***:Twenty healthy servicemen between 20 and 50 years of age and in active duty were eligible for this quantitative,cross-sectional *** measurements took place on a force plate,measuring the mean velocity of the center of *** participants were asked to stand as still as possible in three different foot positions(wide stance,small stance,and on one leg),five times each for 45 s each time,and the measurements were performed with and without real-time visual ***:We observed a significant main effect of foot position(P<0.001),but not of visual feedback(P=0.119)or repetition number(P=0.915).Postural stability decreased in the more challenging foot *** ICC estimates varied from 0.809(one repetition in wide stance)to 0.985(five repetitions on one leg).The common variance(R2)between different foot positions without feedback varied between 0.008(wide stance)and ***:To yield reliable data,wide-stance measurements should be conducted three times,and small-stance measurements and measurements on one leg should be conducted two *** scores of a measurement in a particular foot position cannot predict the scores of measurements in other foot positions.

关键词： Postural stability Center of Pressure Servicemen Intrasession reliability Concurrent validity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Wireless Acoustic Sensor Networks and Edge Computing for Rapid Acoustic Monitoring

引用

IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 64-74页

作者： Zhengguo Sheng saskia Pfersich Alice Eldridge Jianshan Zhou Daxin Tian Victor C.M.Leung the Department of Engineering and Design University of Sussex Infineon Technologies AG the Department of Music University of Sussex Beijing Advanced Innovation Center for Big Data and Brain Computing (BDBC) Beijing Key Laboratory for Cooperative Vehicle Infrastructure Systems & Safety ControlSchool of Transportation Science and EngineeringBeihang University the Department of Electrical and Computer Engineering The University of British Columbia

Passive acoustic monitoring is emerging as a promising solution to the urgent, global need for new biodiversity assessment methods. The ecological relevance of the soundscape is increasingly recognised, and the affordability of robust hardware for remote audio recording is stimulating international interest in the potential for acoustic methods for biodiversity *** scale of the data involved requires automated methods,however, the development of acoustic sensor networks capable of sampling the soundscape across time and space and relaying the data to an accessible storage location remains a significant technical challenge, with power management at its core. Recording and transmitting large quantities of audio data is power intensive,hampering long-term deployment in remote, off-grid locations of key ecological interest. Rather than transmitting heavy audio data, in this paper, we propose a low-cost and energy efficient wireless acoustic sensor network integrated with edge computing structure for remote acoustic monitoring and in situ *** and computation of acoustic indices are carried out directly on edge devices built from low noise primo condenser microphones and Teensy microcontrollers, using internal FFT hardware support. Resultant indices are transmitted over a ZigBee-based wireless mesh network to a destination *** tests of audio quality, indices computation and power consumption demonstrate acoustic equivalence and significant power savings over current solutions.

关键词： Acoustic sensor networks edge computing energy efficiency

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Comparison of Diaton transpalpebral tonometer with applanation tonometry in keratoconus

引用

International Journal of Ophthalmology(English edition) 2016年第3期9卷 395-398页

作者： Robert PL Wisse Natalie Peeters saskia M Imhof Allegonda van der Lelij Utrecht Corneal Research Group Department of Ophthalmology University Medical Center Utrecht Utrecht 3508 GA The Netherlands

AIM： To Investigate the added value of using a Diaton transpalpebral tonometer （DT） to measure lOP in keretoconus. Most type of tonometers use corneal applanation or biomechanical resistance to measure intraocular pressure （lOP）; however, these factors can be altered by keratoconus. Specifically, we examined whether DT can detect false-negative low Goldmann applanation tonometry （AT） measurements. METHODS： Patients with keratoconus were recruited from our tertiary academic treatment center. Measurements included AT and DT （in random order） and Scheimpflug imaging. An age- and gender-matched group of control subjects with no history of corneal disease or glaucoma was also recruited. RESULTS： In total, 130 eyes from 66 participants were assessed. In the keratoconus group, mean AT was 11.0± 2.6, mean DT 11±5.5 （P =0.729）and the two measures were correlated significantly（P=0.006, R=0.323）. However, a Bland-Altman plot revealed a wide distribution and poor agreement between both measurements. Previous corneal crosslinking, corneal pachymetry, and Krumeich classification had no effect on measured IOP. CONCLUSION： Measurements obtained using a Diaton tonometer are not affected by corneal biomechanics; however, its poor agreement with Goldmann AT values calls into question the added value of using a Diaton tonometer to measure lOP in keratoconus.

关键词： Diaton Goldmann applanation tonometry transpalpebral tonometry keratoconus Bland-Altman plot

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Soil Physical Quality of Citrus Orchards Under Tillage, Herbicide, and Organic Managements

引用

Pedosphere 2018年第3期28卷 463-477页

作者： Simone DI PRIMA Jesus RODRIGO-COMINO Agata NOVARA Massimo IOVINO Mario PIRASTRU saskia KEESSTRA Artemi CERDA Dipartimento di Agraria Università degli Studi di Sassari Sassari 07100 Italy Instituto de Geomorfologia y Suelos Department of Geography Mdlaga University Campus of Teatinos sin Mdlaga 29071( Spain) Department of Physical Geography Trier University Trier D-54286( Germany) Dipartimento di Scienze Agrarie Alimentari e Forestali Universita degli Studi di Palermo Palermo 90128( Italy) Team Soil Water and Land Use Wageningen Environmental Research Wageningen UR Droevendaalsesteeg 3 Wageningen 6700 AA(The Netherlands) Civil Surveying and Environmental Engineering The University of Newcastle Callaghan 2308(Australia) Soil Erosion and Degradation Research Group Department of Geography Universitat de Valencia Valencia 46010( Spain)

Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality(SPQ). In this study, the SPQ of citrus orchards was assessed under three different soil managements, namely no-tillage using herbicides, tillage under chemical farming, and no-tillage under organic farming. Commonly used indicators, such as soil bulk density,organic carbon content, and structural stability index, were considered in conjunction with capacitive indicators estimated by the Beerkan estimation of soil transfer parameter(BEST) method. The measurements taken at the L'Alcoleja Experimental Station in Spain yielded optimal values for soil bulk density and organic carbon content in 100% and 70% of cases for organic farming. The values of structural stability index indicated that the soil was stable in 90% of cases. Differences between the soil management practices were particularly clear in terms of plant-available water capacity and saturated hydraulic conductivity. Under organic farming, the soil had the greatest ability to store and provide water to plant roots, and to quickly drain excess water and facilitate root *** practices adopted under organic farming(such as vegetation cover between the trees, chipping after pruning, and spreading the chips on the soil surface) improved the SPQ. Conversely, the conventional management strategies unequivocally led to soil degradation owing to the loss of organic matter, soil compaction, and reduced structural stability. The results in this study show that organic farming has a clear positive impact on the SPQ, suggesting that tillage and herbicide treatments should be avoided.

关键词： Beerkan estimation of soil transfer parameter capacitive indicator organic farming soil management soil quality assessment structural stability index

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Real-world evidence for improved outcomes with histamine antagonists and aspirin in 22,560 COVID-19 patients

引用

Signal Transduction and Targeted Therapy 2021年第8期6卷 2297-2299页

作者： Cameron Mura saskia Preissner Susanne Nahles Max Heiland Philip E.Bourne Robert Preissner School of Data Science and Deportment of Biomedical Engineering University of VirginiaCharlottesvilleVAUSA Department Oral and Maxillofacial Surgery Charite-Universitatsmedizin Berlincorporate member of Freie Universitat BerlinHumboldt-Universitat zu Berlinand Berlin Institute of HealthBerlinGermany Institute of Physiology and Science-IT Charite-Universitatsmedizin Berlincorporate member of Freie Universitat BerlinHumboldt-Universitat zu Berlinand Berlin Institute of HealthBerlinGermany

Dear Editor,The COVID-19 pandemic has driven great interest in the therapeutic potential of repurposed drugs with well-established benefits and safety profiles(toxicity,bioavailability,etc.),many of which act via sign... 详细信息

关键词： drugs category COV

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：