检索结果-南通市图书馆

科研评价改革与科研人员“计量智慧”的异质性（英文）

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 2025年第1期 47-73+232-233页

作者： sandra Rousseau Cinzia Daraio CEDON KU Leuven DIAG Sapienza University of Rome

目的：本研究旨在衡量科研人员对文献计量指标的认知和态度差异，重点是探索各学科内部和学科之间在“计量智慧”上的异质性。设计/方法：本研究通过对欧洲最古老、最大的综合性大学之一——罗马大学的科研人员进行探索性调查，评估其... 详细信息

目的：本研究旨在衡量科研人员对文献计量指标的认知和态度差异，重点是探索各学科内部和学科之间在“计量智慧”上的异质性。设计/方法：本研究通过对欧洲最古老、最大的综合性大学之一——罗马大学的科研人员进行探索性调查，评估其“计量智慧”。我们使用李克特5点量表评估态度，并分析了近期科研评价改革相关的文件，探讨这些改革如何考虑科研人员对于文献计量指标的异质性态度和认知。发现：研究发现，科研人员在“计量智慧”方面存在显著的学科间异质性。此外，在每个学科内部，也同时存在对文献计量指标的支持者和批评者。在文献调研中，我们没有发现关于明确提及科研人员在“计量智慧”方面个体差异的研究。研究局限性：我们使用意大利一所大学的自选科研人员样本作为探索性案例，未来的研究需要验证这些发现的普遍适用性。实践意义：为了获得对科研评价实践的充分支持，考虑科研人员对计量指标的多样化态度是关键。原创性/价值：本研究通过实证测量，为当前科研评价改革的讨论提供了新的视角，探讨了科研人员对文献计量指标的认知和态度，并讨论了这些结果对改进当前科研评价系统的重要性。

关键词：科研评估科研改革计量智慧研究人员异质性文献计量指标研究人员的态度

Physicochemical Properties of Combustion Ashes of Some Trees(Urban Pruning)Present in the Neotropical Region

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2023年第10期11卷 3769-3787页

作者： John Freddy Gelves-Díaz Ludovic Dorkis Richard Monroy-Sepúlveda sandra Rozo-Rincón Yebrail Alexis romero-Arcos Competitiveness and Sustainability for Development Research Group Faculty of EngineeringUniversidad Libre-Cúcuta SectionalCúcutaColombia Catalysis and Nanomaterials Research Group Faculty of MinesUniversidad Nacional de Colombia-Medellín SectionalMedellínColombia

Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion *** accordance with the above,in this paper,we wanted to study the ash from urban pruning residues that are generated in cities in the *** such as Licania tomentosa,Azadirachta indica,Ficus benjamina,Terminalia catappa,Leucaena leucocephala,Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy *** materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence,scanning electron microscopy with microchemistry,BET surface area,thermal gravimetric analysis,and differential scanning *** pH and apparent density were also *** results show high basicity materials(average pH 10),a behavior associated with the presence of chemical elements such as calcium,potassium,magnesium,chlorine,phosphorus,and ***,these materials have a very significant amorphous fraction(between 49%and 74.5%),the dominant crystalline phases are calcite,arcanite,sylvite,and *** ashes have low surface area and do not exceed 13 m^(2)/*** characteristic morphological aspects were observed in these ashes:a morphology of rounded grains where silicon content is highlighted,and lamellar morphologies where the presence of chlorine is ***,these ashes show four significant mass loss events(400℃,430℃,680℃,and 920℃),causing mass losses that vary between 25%and 40%.Through this study,it was possible to establish that,from a chemical point of view,these ashes are less dangerous in comparison with those of a mineral coal that was used as a ***,they require additional treatments for their disposal due to their high *** of their composition,these ashes have the potential to be used in the ceramic and cement industries,and in the manuf

关键词： Bottom ash chemical composition characterization mineralogy plant biomass pruning residues urban flora

Assessment of food supplementation and surveillance as techniques to reduce damage caused by black capuchin monkeys Sapajus nigritus to forest plantations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2014年第5期60卷 581-590页

作者： sandra Bos MIKICH Laboratory of Ecology (Laborat6rio de Ecologia) Embrapa Florestas Caixa Postal 319 CEP 83411-000 Colombo PR Brazil Black Capuchin Monkey Program (Programa Macaco-prego) National Fund for the Control of Forest Pests (Fundo Nacional de Controle de Pragas Florestais) Dieter Liebsch Environmental Consulting (Dieter Liebsch Consultoria Ambiental) Curitiba PR Brazil dieterliebsch@yahoo.com.br

Black capuchin monkeys Sapajus nigritus are among several mammalian species that damage forest plantations, pri- marily plantations of pine trees （Pinus spp.） in South Brazil. Management practices to reduce these damages include supplemen- tary food offerings and plantation surveillance. To assess the efficiency of these techniques, four treatments were evaluated： feeding （F, with supplementary bananas and maize）, surveillance （S, in situ, wherein men patrolled the plantations, deterring the monkeys）, feeding ＋ surveillance （FS） and control （no procedures）（C）. The efficiency assessment of each treatment involved the number of recorded primate sightings in the treatments with the presence of guards （S and FS） and a damage inventory of the outskirts of the experimental points immediately before and after the experiment. These data were complemented by a simulta- neous study of the availability of fruit, the primary item in the diet of this primate species, in the remnant native forest in the study area. Most sightings of S. nigritus occurred early in the morning, and in general, sightings were inversely proportional to the availability of native fruits. This trend was most evident in treatment FS, most likely due to the presence of food. Treatments F and FS exhibited higher percentages of damage, indicating that these are inefficient management techniques. Treatment S exhi- bited the lowest damage rate, but at a high cost, making this technique difficult to apply over large expanses. The development of other management techniques, such as environmental enrichment and the use of deterrents, is recommended to minimize the damage caused by capuchins in forest plantations [Current Zoology 60 （5）： 581-590, 2014].

关键词： Cebus Damage control Wildlife management Pinus Food provisioning

Pork Meat Quality of Preto Alentejano and Commercial Largewhite Landrace Cross

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 Integrative Agriculture 2013年第11期12卷 1961-1971页

作者： Alfredo Teixeira sandra Rodrigues Veterinary and Animal Reserch Centre (CECAV) Agrarian School of Polytechnic Institute of BraganaCampus Sta Apolónia Apt.1172Bragan a 5301-855Portugal Mountain Research Centre(CIMO) Agrarian School of Polytechnic Institute of BraganaCampus Sta Apolónia Apt.1172Bragan a 5301-855Portugal

This work aimed to evaluate the physical-chemical characteristics of pork from a local breed （Portuguese black pork called Preto Alentejano） and a commercial breed. Sixteen animals were used, 4 females and 4 males from each breed. Animals had 80-100 kg of live weight. The longissimus muscle between the 5th thoracic vertebra and the 10th lumbar vertebra was used in the analysis. Samples were analysed for protein, fat, pigments, ashes, dry mater, water-holding capacity, and texture. Results of fat and pigments contents indicate signiifcant （P〈0.05 and P〈0.01） differences for all treatments. For protein, ashes, dry mater, water-holding capacity and texture, no signiifcant differences were found for sex. In the analysis of fatty acids composition, ten were detected, being the main ones C16：0, C18：0, C16：1, C18：1, C18：2. There was a predominance of monounsaturated fatty acids （MUFA）, followed by saturated （SFA） and polyunsaturated （PUFA）. Differences were signiifcant for sex （P〈0.01） and breed （P〈0.01）. Preto Alentejano breed and females presented the higher percentages of SFA （P〈0.01） and MUFA （P〈0.001） fatty acids. Differences between breeds might be due to breed production system and feed differences.

关键词： breed sex pork meat quality

维普期刊数据库

Hyper-chaos encryption using convolutional masking and model free unmasking

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2014年第5期23卷 161-166页

作者：齐国元 sandra Bazebo Matondo Department of Electrical Engineerin Tshwane University of Technology Pretoria

In this paper, during the masking process the encrypted message is convolved and embedded into a Qi hyper-chaotic system characterizing a high disorder degree. The masking scheme was tested using both Qi hyper-chaos and Lorenz chaos and indicated that Qi hyper-chaos based masking can resist attacks of the filtering and power spectrum analysis, while the Lorenz based scheme fails for high amplitude data. To unmask the message at the receiving end, two methods are proposed. In the first method, a model-free synchronizer, i.e. a multivariable higher-order differential feedback controller between the transmitter and receiver is employed to de-convolve the message embedded in the receiving signal. In the second method, no synchronization is required since the message is de-convolved using the information of the estimated derivative.

关键词： Qi hyper-chaos masking high-order differentiator chaos-based encryption

维普期刊数据库

Compaction analysis and optimisation of convex-faced pharmaceutical tablets using numerical techniques

在线全文

学校读者我要写书评

暂无评论

Particuology 2019年第6期17卷 10-21页

作者： Ahmad Baroutaji sandra Lenihan Keith Bryan School of Engineering Faculty of Science and EngineeringUniversity of WolverhamptonTelfordUK School of Mechanical Electrical and Process EngineeringCork Institute of TechnologyCorkIreland

Capping failure,edge chipping,and non-uniform mechanical properties of convex-faced pharmaceutical tablets are common problems in the pharma *** this paper,the finite element method(FEM)and design of experiment techniques are used to determine the optimal shape of convex-faced(CF)pharmaceutical tablet which has more uniform mechanical properties and less capping and chipping *** effects of different geometrical parameters and friction on the compaction responses of convex-faced pharmaceutical tablets were first identified and *** FEM model of the tabletting process was generated using the implicit code ABAQUS and validated against experimental *** surface methodology was used to establish the relationship between the design variables,represented by the geometrical parameters and friction coefficient,and compaction responses of interest including residual die pressure,relative density variation within a tablet,and relative shear stress at the edge of a tablet.A statistical-based optimisation approach was then used to optimise the shape of CF *** obtained results demonstrated how the geometrical parameters and friction coefficient of CF pharmaceutical tablets strongly affect their compaction behaviour and quality.

关键词： Capping failure Edge chipping Tabletting FEM Optimisation Residual radial pressure

Accuracy Analysis for Explicit-Implicit Finite Volume Schemes on Cut Cell Meshes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2024年第4期6卷 2239-2264页

作者： sandra May Fabian Laakmann Department of Information Technology Uppsala UniversityBox 33775105UppsalaSweden Mathematical Institute University of OxfordOX26GGOxfordUK

The solution of time-dependent hyperbolic conservation laws on cut cell meshes causes the small cell problem:standard schemes are not stable on the arbitrarily small cut cells if an explicit time stepping scheme is used and the time step size is chosen based on the size of the background *** May and Berger(J Sci Comput 71:919–943,2017),the mixed explicit-implicit approach in general and MUSCL-Trap(monotonic upwind scheme for conservation laws and trapezoidal scheme)in particular have been introduced to solve this problem by using implicit time stepping on the cut *** and numerical results have indicated that this might lead to a loss in accuracy when switching between the explicit and implicit time *** this contribution,we examine this in more detail and will prove in one dimension that the specific combination MUSCL-Trap of an explicit second-order and an implicit second-order scheme results in a fully second-order mixed *** this result is unlikely to hold in two dimensions,we also introduce two new versions of mixed explicit-implicit schemes based on exchanging the explicit *** present numerical tests in two dimensions where we compare the new versions with the original MUSCL-Trap scheme.

关键词： Cartesian cut cell method Finite volume scheme Embedded boundary grid Mixed explicit-implicit Truncation error Error accumulation

Measurements of Laminar Burning Velocities of Alternative Fuels:Application in Transport and Aerospace

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 Thermal Science 2023年第2期32卷 503-512页

作者： RICHTER sandra BRAUN-UNKHOFF Marina NAUMANN Clemens German Aerospace Center(DLR) Institute of Combustion TechnologyDepartment of Chemical Kinetics and AnalyticsStuttgart 70569Germany

The laminar burning velocity belongs to the fundamental combustion properties of fuels being a measure for their heat release,flame length,as well as reactivity and combustion stability,and thus,may impact the design of burners and combustion ***,these experimental data are needed for the validation and optimization within the construction and development of detailed chemical kinetic reaction *** this study,an overview of the different applications of fuel characterization regarding the specific area of interest(road transport,aviation,and aerospace)will be *** on the application,effects of different molecular characteristics on the laminar burning velocity are evaluated:the presence of oxygen atoms and the grade of branching in a specific fuel molecule as well as the difference in the type of a chemical bond,here,single and double *** of alternative fuels being discussed in the present study are:(Ⅰ)oxymethylene ether(OMEn)in the field of road transport;(Ⅱ)a paraffinic Alcohol-to-Jet fuel as sustainable aviation fuel;and(Ⅲ)mixtures of ethane or ethene with nitrous oxide as green propellants for rocket propulsion applications.

关键词： laminar burning velocity alternative sustainable fuels road transport aviation fuels green propellants

维普期刊数据库

Fruit availability, frugivore satiation and seed removal in 2 primate-dispersed tree species

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2011年第3期6卷 178-194页

作者： sandra RATIARISON Pierre-Michel FORGET Department of Ecology and Management of Biodiversity Museum of Natural History Museum(MNHN)BrunoyFrance and oological Society of London LibrevilleGabon

During a mast-fruiting event we investigated spatial variability in fruit availability,consumption,and seed removal at two sympatric tree species,Manilkara bidentata and ***(Sapotaceae)at Nouragues Natural Reserve,French *** addressed the question of how Manilkara density and fruits at the community level might be major causes of variability in feeding assemblages between tree *** thus explored how the frugivore assemblages differed between forest patches with contrasting relative Manilkara density and fruiting *** the daytime,Alouatta seniculus was more often observed in *** crowns at Petit Plateau(PP)with the greatest density of Manilkara *** the lowest fruit diversity and availability,whereas Cebus apella and Saguinus midas were more often observed in *** crowns at both Grand Plateau(GP),with a lowest density of *** and overall greater fruit supply,and ***,nearly 53%and 15%of the *** seed crop at GP and PP,respectively,and about 47%of the *** seed crop were removed,otherwise either spit out or defecated beneath trees,or dropped in ***-bodied primates concentrated fallen seeds beneath parent trees while large-bodied primate species removed and dispersed more seeds away from ***,among the latter,satiated *** wasted seeds under conspecific trees at *** in feeding assemblages,seed removal rates and fates possibly reflected interactions with extra-generic fruit species at the community level,according to feeding choice,habitat preferences and ranging patterns of primate species.

关键词： frugivores masting primates satiation seed dispersal