检索结果-南通市图书馆

Comparative analysis of ceramic-carbonate nanocomposite fuel cells using composite GDC/NLC electrolyte with different perovskite structured cathode materials

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2018年第1期12卷 162-173页

作者： Muhammad i. Asghar Sakari Lepikko janne Patakangas janne Halme Peter D. Lund New Energy Technologies Group Department of Applied Physics Aalto University P.O. BOX 15100 FI-00076 Aalto Finland

A comparative analysis of perovskite structured cathode materials, La0.65Sr0.35Mn03 （LSM）, La0.8Sr0.2CoO3 （LSC）, La0.6Sr0.4FeO3 （LSF） and La0.6Sr0.4Co0.2Fe0.803 （LSCF）, was performed for a ceramic-carbonate nanocomposite fuel cell using composite electrolyte consisting of Gd0.1Ce0.9O1.95 （GDC） and a eutectic mixture of Na2CO3 and Li2CO3. The compatibility of these nanocomposite electrode powder materials was investigated under air, CO2 and air/CO2 atmospheres at 550 ℃. Microscopy measurements together with energy dispersive X-ray spectroscopy （EDS） elementary analysis revealed few spots with higher counts of manganese relative to lanthanum and strontium under pure CO2 atmosphere. Furthermore, electrochemical impedance （EiS） analysis showed that LSC had the lowest resistance to oxygen reduction reaction （ORR）（14.12 Ω·cm^2） followed by LSF （15.23 Ω·cm^2）, LSCF （19.38Ω·cm^2） and LSM （〉 300 Ω·cm^2）. in addition, low frequency EiS measurements （down to 50 gHz） revealed two additional semi-circles at frequencies around 1 Hz. These semicircles can yield additional information about electrochemical reactions in the device. Finally, a fuel cell was fabricated using GDC/NLC nanocomposite electrolyte and its composite with NiO and LSCF as anode and cathode, respectively. The cell produced an excellent power density of 1.06 W/cm^2 at 550 ℃ under fuel cell conditions.

关键词： electrode fuel cell low-temperature nano- composite perovskite

Applications of,and Experiences with,the Norwegian Model in Finland

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

Journal of Data and information Science 2018年第4期3卷 31-44页

作者： janne Polonen Federation of Finnish Learned Societies Snellmaninkatu 1300170HelsinkiFinland

The purpose of this article is to describe the development, components and properties of a publication indicator that the Ministry of Education and Culture in Finland uses for allocating direct core funding annually to universities. Since 2013, 13% of the core funding has been allocated on basis of publication indicator that, like the Norwegian model, is based on comprehensive national level publication data that is currently provided by the ViRTA publication information service. in 2015, the publication indicator was complemented with other components of the Norwegian model, namely, quality-weighted publication counts based on national Publication Forum authority list of the publication channels with ratings established by experts in the field. The funding model allocates around 1.6 billion euros annually to universities with the publication indicator annually distributing over 200 million euros. Besides the funding model, the indicator provides comparable data for monitoring the research performance of Finnish universities, fields and subunits. The indicator may also be used in the universities' local funding models and research management systems, sometimes even at individual level evaluation. Positive and negative effects of the indicator have been extensively discussed and speculated. Since 2011, the Finnish universities' productivity appears to have increased in terms of both quantity and quality of publications.

关键词： Performance-based funding Research policy Research management Bibliometrics

Control of exterior ballistic properties of spin-stabilized bullet by optimizing internal mass distribution

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2019年第1期15卷 38-50页

作者： janne Lahti Timo Sailaranta Mikko Harju Kai Virtanen Systems Analysis Laboratory Department of Mathematics and Systems AnalysisAalto University Aero RD Ltd Systems Analysis Laboratory Department of Mathematics and Systems AnalysisAalto Universit Department of Military Technology National Defence University of Finland

This paper introduces a novel approach for controlling the exterior ballistic properties of spin-stabilized bullets by optimizing their internal mass distributions. Specifically, the properties of interest are the bullets’ stability characteristics that are examined through dynamic and gyroscopic stability *** analytical expressions for aerodynamic quantities are also derived to address the compressibility of air. These expressions are utilized in a bullet model that enables efficient computation of the stability parameters for a given mass distribution. The bullet model is used in the formulation of nonlinear optimization problems that provide optimal mass distributions with respect to given goals, i.e., desired stability characteristics. The bullet types investigated in this paper are a long range bullet and a limited range training bullet. in the optimization of the mass distribution of the long range bullet, the goal is that the bullet stays stable for as long as possible. The mass distribution of the training bullet is optimized such that the bullet is stable at launch but becomes unstable shortly afterwards. The global optimal solutions obtained with the new approach fulfill the desired stability characteristics better than currently used uniformly filled bullets. Overall, the optimization approach reveals a new goal focused philosophy for bullet design compared to current trial and error design practices.

关键词： Aerodynamics Bullet Exterior ballistics Mass properties Optimization Stability

Tectonics and architectonic quality in recently published Finnish log architecture:Corresponding architects’perceptions

在线全文

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2021年第4期10卷 741-757页

作者： Matti Lakkala janne Pihlajaniemi Oulu School of Architecture University of OuluOulu90570Finland

Due to the global increase in wood construction,it is crucial for architects to understand *** Finland,log building,a special subset of industrially manufactured massive timber construction materials is experiencing a *** aspects combined with newer technical developments make log a complex material from the viewpoint of architectonic *** inform practicing architects,the aim of this study is to explore how the tectonics of logs contribute to the architectonic quality of log *** interviews among architects of twelve recently published log buildings are *** results describe how architectonic quality is perceived among participants,and features of logs related to tectonics that they consider to be of importance in terms of architectonic *** features include the statics of log construction and log’s nature as a simultaneously insulating,load-bearing and visual *** between industrial and hand-hewn logs,as well as other architectural aspects of using logs in contemporary architecture are *** the“non-settling”log was perceived to have manifold implications for the architectonic possibilities of log *** results are of practical importance to designing architects and the log *** implications include tangible information on architectonic quality and tectonics of log building.

关键词： Log building Log architecture Architect perceptions Architectonic quality Tectonic theory in architecture Design ethnography

Specialist predator in a multi-species prey community:boreal voles and weasels

在线全文

学校读者我要写书评

暂无评论

integrative Zoology 2008年第1期3卷 51-63页

作者： janne SUNDELL Hannu YLÖNEN Metapopulation Research Group Department of Biological and Environmental SciencesUniversity of HelsinkiHelsinkiFinland Konnevesi Research Station Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland

Dissimilar vulnerabilities of different prey types and preferences of predators are factors likely to contribute to community *** may happen via differential individual properties of prey animals(***,escape)or via habitat effects making hunting by a predator easier and more rewarding in some habitats,or ***,community dynamics may be influenced by predator mediated apparent competition,in which an increase in one prey type has negative effects on another prey type indirectly via the shared *** summarize the current knowledge from the field in a model predator–prey system consisting of sympatric boreal vole species and their common specialist predator and review field studies using predator manipulation and studies on the responses of individuals in the laboratory and in outdoor *** vole species studied represent different prey types that are thought to have different *** observations on the main resident specialist predator,the least weasel(Mustela nivalis nivalis L.),show that it hunts according to prey availability and suitability of the hunting *** voles respond to the presence of the predator behaviorally in various ways to avoid *** conclude that even if the least weasel is a specialized predator of small rodents it acts like a generalist predator within the small rodent guild and may facilitate the coexistence of prey species via predator *** may lead to interspecific synchrony between prey populations,which has often been *** suggest that the processes determining the community impact of predator–prey interactions are driven by the behavioral arms race between the predator and the prey,together with the habitat-dependent density of prey and net gain for the predator.

关键词： apparent competition predator–prey interaction prey choice vole cycle

Exponential Polynomials as Solutions of Certain Nonlinear Difference Equations

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

Acta Mathematica Sinica,English Series 2012年第7期28卷 1295-1306页

作者： Zhi Tao WEN janne HEiTTOKANGAS ilpo LAiNE Department of Physics and Mathematics University of Eastern Finland

Recently, C.-C. Yang and L Laine have investigated finite order entire solutions f of non- linear differential-difference equations of the form f^n ＋ L（z, f） -= h, where n ≥ 2 is an integer. in particular, it is known that the equation f（z）^2 ＋ q（z）f（z ＋ 1） = p（z）, where p（z）, q（z） are polynomials, has no transcendental entire solutions of finite order. Assuming that Q（z） is also a polynomial and c E C, equations of the form f（z）^n ＋ q（z）e^Q（Z）f（z ＋ c） = p（z） do posses finite order entire solutions. A classification of these solutions in terms of growth and zero distribution will be given. in particular, it is shown that any exponential polynomial solution must reduce to a rather specific form. This reasoning relies on an earlier paper due to N. Steinmetz.

关键词： Convex hull difference equation entire solution exponential polynomial Nevanlinna theory

Historical Bibliometrics Using Google Scholar: The Case of Roman Law, 1727–2016

在线全文

学校读者我要写书评

暂无评论

Journal of Data and information Science 2020年第3期5卷 18-32页

作者： janne Polonen Bjorn Hammarfelt Federation of Finnish Learned Societies Snellmaninkatu 1300170 HelsinkiFinland Swedish School of Library and information Science University of BorasAllegatan 1Boras50332Sweden

Purpose: The purpose of this study is to investigate the historical and linguistic coverage of Google Scholar, using publications in the field of Roman law as an ***/methodology/approach: To create a dataset of Roman law publications, we retrieved a total of 21,300 records of publications, published between years 1500 and 2016, with title including words denoting "Roman law" in English, French, German, italian, and Spanish. Findings: We were able to find publications dating back to 1727. The largest number of publications and authors date to the late 19th century, and this peak might be explained by the role of Roman law in French legal education at the time. Furthermore, we found exceptionally skewed concentration of publications to authors, as well as of citations to publications. We speculate that this could be explained by the long time-frame of the study, and the importance of classic works. Research limitation: Major limitations, and potential future work, relate to data quality, and cleaning, disambiguation of publications and authors, as well as comparing coverage with other data sources. Practical implications: We find Google Scholar to be a promising data source for historical bibliometrics. This approach may help bridge the gap between bibliometrics and the "digital humanities".Originality/value: Earlier studies have focused mainly on Google Scholar's coverage of publications and citations in general, or in specific fields. The historical coverage has, however, received less attention.

关键词： Historical bibliometrics Google Scholar Roman law

On the potential to predetermine dominant tree species based on sparse-density airborne laser scanning data for improving subsequent predictions of species-specific timber volumes

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2016年第2期3卷 95-111页

作者： janne Raty Jari Vauhkonen Matti Maltamo Timo Tokola University of Eastern Finland School of Forest Sciences Yliopistokatu 7 P.O.Box 111FI-80101 Joensuu Finland

Background： Tree species recognition is the main bottleneck in remote sensing based inventories aiming to produce an input for species-specific growth and yield models. We hypothesized that a stratification of the target data according to the dominant species could improve the subsequent predictions of species-specific attributes in particular in study areas strongly dominated by certain species. Methods： We tested this hypothesis and an operational potential to improve the predictions of timber volumes, stratified to Scots pine, Norway spruce and deciduous trees, in a conifer forest dominated by the pine species. We derived predictor features from airborne laser scanning （ALS） data and used Most Similar Neighbor （MSN） and Seemingly Unrelated Regression （SUR） as examples of non-parametric and parametric prediction methods, respectively Results： The relationships between the ALS features and the volumes of the aforementioned species were considerably different depending on the dominant species. incorporating the observed dominant species inthe predictions improved the root mean squared errors by 13.3-16.4 % and 12.6-28.9 % based on MSN and SUR, respectively, depending on the species. Predicting the dominant species based on a linear discriminant analysis had an overall accuracy of only 76 % at best, which degraded the accuracies of the predicted volumes. Consequently, the predictions that did not consider the dominant species were more accurate than those refined with the predicted species. The MSN method gave slightly better results than models fitted with SUR. Conclusions： According to our results, incorporating information on the dominant species has a clear potential to improve the subsequent predictions of species-specific forest attributes. Determining the dominant species based solely on ALS data is deemed challenging, but important in particular in areas where the species composition is otherwise seemingly homogeneous except being dominated by certain species

关键词： Forest inventory Light Detection and Ranging (LiDAR) Area-based approach Nearest neighbor estimation,Crown base height intensity Volume model

Meromorphic Functions of Finiteφ-order and Linear Askey-Wilson Divided Difference Equations

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2022年第2期38卷 371-383页

作者： Hui YU janne HEiTTOKANGAS Jun WANG Zhi Tao WEN Department of Physics and Mathematics University of Eastern FinlandP.O.Box 11180101 JoensuuFinland School of Mathematical Sciences Fudan UniversityShanghai 200433P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

The growth of meromorphic solutions of linear difference equations containing Askey-Wilson divided difference operators is ***φ-order is used as a general growth indicator,which covers the growth spectrum between the... 详细信息

关键词： Askey-Wilson divided difference operator Askey-Wilson divided difference equation lemma on the logarithmic