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Journal of Green Building 2016年第2期11卷 75-92页

作者： Jorge S.carlos C-MADE Centre of Materials and Building TechnologiesUniversity of Beira InteriorCalçada Fonte do Lameiro6200-358 CovilhãPortugal

This paper investigates the main characteristics of daylight on any window in a street *** sky component and the light reflected from the surroundings are described to determine the vertical daylight factor(VDF).Several street canyon types are characterized taking into account their different height/width and any level of the window is analysed.A simple calculation method uses trigonometric equations based on the sky and the geometry of the *** results were previ-ously evaluated considering different daylight procedures obtained by other *** study reveals that the reflectance within an urban canyon plays an important role in the amount of daylight onto any window with more relevance in a deep canyon and low sky *** graphical presentation that result from this investiga-tion can rapidly assist building and urban designers in an early stage design where assumptions and the lay out of the main design take place.

关键词： vertical daylight factor urban canyon configuration factor diffuse light isotropic overcast sky

3D non-stationary wideband circular tunnel channel models for high-speed train wireless communication systems

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Science China(Information Sciences) 2017年第8期60卷 189-201页

作者： Yu LIU Cheng-Xiang WANG carlos LOPEZ Xiaohu GE Shandong Provincial Key Lab of Wireless Communication Technologies Shandong University Institute of Sensors Signals and Systems School of Engineering & Physical Sciences Heriot-Watt University Department of Electronics and Information Engineering Huazhong University of Science and Technology

This paper proposes three-dimensional(3D) non-stationary wideband circular geometry-based stochastic models(GBSMs) for high-speed train(HST) tunnel scenarios. Considering single-bounced(SB)and multiple-bounced(MB) components from the tunnel’s internal surfaces, a theoretical channel model is first established. Then, the corresponding simulation model is developed using the method of equal volume(MEV)to calculate discrete angular parameters. Based on the proposed 3D GBSMs, important time-variant statistical properties are investigated, such as the temporal autocorrelation function(ACF), spatial cross-correlation function(CCF), and space-Doppler(SD) power spectrum density(PSD). Results indicate that all statistical properties of the simulation model, verified by simulation results, can match well those of the theoretical *** statistical properties of the proposed 3D GBSMs are further validated by relevant measurement data,demonstrating the flexibility and utility of our proposed tunnel GBSMs.

关键词： non-stationary statistical properties tunnel channel model GBSM channel measurement

Experimental and numerical study of fence effects on dust emission into atmosphere from open storage piles

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Journal of Central South University 2011年第2期18卷 411-419页

作者： S.TORNO J.TORA-O M MENéNDEZ M.GENT I.álvarez Mining and Civil Works Research Group Oviedo University School of Mines Oviedo University

The results obtained from the research on the behaviour of fences (solid and porous) in the protection against particulated material emission to the atmosphere from open storage piles,are presented. This research was carried out through computational fluid dynamics (CFD) simulation by software Ansys CFX-10.0 in 3D,with K-epsilon being considered in the turbulence model. The efficiency of the use of porous fences as a protection against the wind flow,which interacts with an open storage pile,is shown. The use of these fences (when porosity is ε=30%) allows the reduction of wind flow velocity which interacts with the pile in comparison with the case of no use of fences (when porosity is 100%). In addition,the use of porous fences makes the velocity vortex,which is formed between the solid fence (ε=0%) and the pile,disappear,reducing the particle emission to the atmosphere by 78%.

关键词： open storage pile air pollution particle emission wind erosion porous fence computational fluid dynamics

OPTIMAL WINDOW GEOMETRY FACTORS FOR ELEMENTARY SCHOOL BUILDINGS IN PORTUGAL

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Journal of Green Building 2018年第1期13卷 185-197页

作者： Jorge S.carlos Centre of Materials and Building Technologies(CMADE-UBI) Universidade da Beira InteriorRua Marquês D’Ávila e Bolama6200-001CovilhãPortugal

INTRODUCTION With respect to thermal performance, windows are the weakest component of the building envelope, essentially because the U-value is usually higher than the opaque envelope. This would allow the highest heat conductance of the building envelope. However, it also helps buildings to gain useful solar heat during winter. Therefore, it has been generally accepted that passive buildings would have small windows towards the poles and large windows facing the equator (Persson, Roos, and Wall 2006). In spite of this guideline, large or fully glazed facades have been used in modern architecture. The intensive use of air conditioning is the result of overheating and high thermal loss problems, which otherwise would lead to thermal discomfort. This extensive use of large windows associated with high energy consumption has motivated researchers to study this building component. Window areas were investigated by Persson et al. (Persson, Roos, and Wall 2006) on 20 terraced houses with larger windows facing the equator and built in Gothenburg. The building envelope was well insulated and fitted with energy efficient windows. It was found that energy efficient windows do not have a major influ-ence on the heating demand in the winter, but it is relevant for the cooling need in summer. Therefore, reduced indoor illuminance due to small windows can be solved by enlarging them in order to obtain relevant daylighting conditions. When efficient windows are designed for a warm climate, as in Mexico, reducing heat flux and solar transmittance indoors was the best option for energy savings (Aguilar et al. 2017). However, reducing solar transmittance influences the indoor illuminance, which was not analyzed.

关键词： school building classroom windows solar heat gain daylight

Factors affecting populations of the endemic Iberian hare(Lepus granatensis)after the first myxomatosis outbreaks in Central Spain

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Integrative Zoology 2023年第6期18卷 981-993页

作者： carlos LÁZARO JoséLuis GUZMÁN Fabián CASAS carlos SÁNCHEZ-GARCÍA Department of Research Fundación ArtemisanCiudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain

The Iberian hare(Lepus granatensis)is an endemic species distributed in Spain and *** outbreaks affecting this species were detected in 2018 in Central and Southern Spain,spreading *** to evaluate factors affecting the status of hare population after the arrival of myxomatosis,we conducted 108 nocturnal hare counts in Central Spain during two study periods(winter/spring and summer/autumn)in 54 different hunting grounds,covering 1071 km and observing 884 *** mean density in winter/spring was 7.66 hares/100 ha,(range 6.14-9.54/100 ha),while in summer/autumn,it was 3.4 hares/100 ha(range 2.6-4.4/100 ha).Densities of hares were not affected by the dominant habitat and the presence/absence of myxomatosis *** were more abundant at hunting grounds at a higher altitude and in those conducting targeted management,while detection of myxomatosis was related to lower altitude and higher levels of game management.A MaxEnt model used to generate a risk map for myxomatosis occurrence showed that the temperature annual range was the most important predictor,which suggests that environmental factors affecting myxomatosis vectors(mosquitoes,fleas,and ticks)could play a key role in disease *** myxomatosis in hares is becoming endemic,hare densities may be improved by game management and the monitoring and surveillance of this emerging *** surveillance programs could be the basis of effective collaborations between hunters,researchers,and environmental managers.

关键词： game management habitat Iberian hare MaxEnt monitoring myxomatosis

Effects of vegetation cover on recruitment of Ulmus pumila L. in Horqin Sandy Land, northeastern China

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Journal of Arid Land 2014年第3期6卷 343-351页

作者： DeMing JIANG Yi TANG carlos A BUSSO Institute of Applied Ecology Chinese Academy of Sciences Agronomy Department National University of the South and CERZOS (CONICET)

Understanding the effects of vegetation cover on seedling survival is helpful for promoting vegetation restoration in environmentally fragile zones. This study was conducted in the desertified, moving sand dunes of Horqin Sandy Land, Inner Mongolia, northeastern China. We hyphothesized that （1） seed density （i.e., number/m2） increases as vegetation cover increases, and （2） there will be more surviving seedlings in locations with higher vegetation covers. Total vegetation cover and initial densities of seeds, germinated seeds and surviving seedlings of Ulmus pumilia were evaluated under various vegetation covers in trying to clarify the effects of vegetation cover on the early stages of the plant life history. In agreement with the first hypothesis, initial seed densities were greater （P〈0.05） under higher vegetation covers. The relationship between vegetation cover and initial seed density was represented by a quadratic regression, where a threshold occurred with a vegetation cover of 36% （P〈0.05）. The higher total vegetation covers, however, did not result in increased densities of germinated seeds （P〉0.05）, which on average represented 16.7% of initial seed densities. Even more, three months after the study initiation, total vegetation covers were similar （P〉0.05） at all positions in the dunes, and they determined a similar number （P〉0.05） of surviving seedlings at those positions （i.e. the second hypothesis had to be rejected）. The mean number of seedlings that survived at all positions was only 4.5% of germinated seeds. The number of surviving elm seedlings （0 to 1.7 seedlings/m2） under various vegetations covers （12.2% to 20.8%） at all dune positions by late summer would most likely not contribute to vegetation restoration in the study area.

关键词： arid and semiarid zones elm seed dispersal seed germination seedling survival

Developing a dynamic growth model for teak plantations in India

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Forestry Studies in China 2014年第2期16卷 71-80页

作者： Vindhya Prasad Tewari Juan Gabriel lvarez-gonzález Oscar García Forest Biometry Division Institute of Wood Science and TechnologyBangaloreIndia Unidad de Gestión Forestal Sostenible Departamento de Ingenieria AgroforestalUniversidad de Santiago de CompostelaLugoSpain University of Northern British Columbia ColumbiaBCCanada

Background： Tectono grandis （teak） is one of the most important tropical timber species occurring naturally in India. Appropriate growth models, based on advanced modeling techniques, are not available but are necessary for the successful management of teak stands in the country. Long-term forest planning requires mathematical models and the principles of Dynamical System Theory provide a solid foundation for these. Methods： The state-space approach makes it possible to accommodate disturbances and avarying environment. In this paper, an attempt has been made to develop a dynamic growth model based on the limited data, consisting of three annual measurements, collected from 22 teak sample plots in Karnataka, Southern India. Results： A biologically consistent whole-stand growth model has been presented which uses the state-space approach for modelling rates of change of three state-variables viz., dominant height, stems per hectare and stand basal area. Moreover, the model includes a stand volume equation as an output function to estimate this variable at any point in time. Transition functions were fitted separately and simultaneously. Moreover, a continuous autoregressive error structure is also included in the modelling process. For fitting volume equation, generalized method of moments was used to get efficient parameter estimates under heteroscedastic conditions. Conclusions： A simple model containing few free parameters performed well and is particularly well suited to situations where available data is scarce.

关键词： Mortality Basal area Canopy closure Relative occupancy State-space approach Tectona grandis

Light losses in hollow, prismatic light guides related to prism defects: a transmittance model

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Chinese Optics Letters 2015年第9期13卷 68-72页

作者： Berta García-Fernández Daniel Vázquez-Moliní Antonio álvarez Fernández-Balbuena Angel García-Botella Juan carlos Martínez Antón Department of Optics Faculty of Optics and Optometry University Complutense of Madrid Department of Physics Applied to Natural Resources School of Forestry EngineeringPolytechnic University of Madrid

Hollow, cylindrical, prismatic light guides （CPLGs） are optical components that, using total internal reflection （TIR）, are able to transmit high-diameter light beams in daylight and artificial lighting applications without relevant losses. It is necessary to study the prism defects of their surfaces to quantify the behavior of these optical components. In this Letter, we analyze a CPLG made of a transparent dielectric material. Scanning electron microscopy （SEM） and the topographic optical profilometry by absorption in fluids （TOPAF） imaging tech- nique are conducted to determine if there are defects in the corners of the prisms. A model for light guide trans- mittance that is dependent on prism defects is proposed. Finally, a simulation and an experimental study are carried out to check the validity of the proposed model.

关键词： Light losses in hollow a transmittance model prismatic light guides related to prism defects

Meteorological drought features in northern and northwestern parts of Mexico under different climate change scenarios

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Journal of Arid Land 2017年第1期9卷 65-75页

作者： carlos ESCALANTE-SANDOVAL Pedro NUNEZ-GARCIA Faculty of Engineering National Autonomous University of Mexico Cd. Universitaria Coyoacan 04510 Mexico

Meteorological drought has been an inevitable natural disaster throughout Mexican history and the northern and northwestern parts of Mexico（i.e., the studied area）, where the mean annual precipitation（MAP） is less than 500 mm, have suffered even more from droughts in the past. The aim of this study was to conduct a meteorological drought analysis of the available MAP data（1950–2013） from 649 meteorological stations selected from the studied area and to predict the drought features under the different IPCC-prescribed climate change scenarios. To determine the long-term drought features, we collected 1×10~4 synthetic samples using the periodic autoregressive moving average（PARMA） model for each rainfall series. The simulations first consider the present prevailing precipitation conditions（i.e., the average from 1950 to 2013） and then the precipitation anomalies under IPCC-prescribed RCP 4.5 scenario and RCP 8.5 scenario. The results indicated that the climate changes under the prescribed scenarios would significantly increase the duration and intensity of droughts. The most severe impacts may occur in the central plateau and in the Baja California Peninsula. Thus, it will be necessary to establish adequate protective measures for the sustainable management of water resources in these regions.

关键词： meteorological drought synthetic simulation climate change water stress evapotranspiration

Pannexin 1-based channels activity as a novel regulator of multiple sclerosis progression

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Neural Regeneration Research 2020年第1期15卷 65-66页

作者： Fernando C.Ortiz carlos Puebla Mechanisms on Myelin Formation and Repair Laboratory Instituto de Ciencias BiomedicasFacultad de Ciencias de la SaludUniversidad Autonoma de ChileSantiagoChile Cellular Physiology Laboratory Instituto de Ciencias BiomedicasFacultad de Ciencias de la SaludUniversidad Autonoma de ChileSantiagoChile

Multiple sclerosis(MS):MS is a neurodegenerative disease affecting around 2.5 million people worldwide,representing the second cause of disabilities in the young adult *** is a demyelinating pathology which originates in the autoimmune attack of T and B lymphocytes against *** lack of myelin leads,in turn,to axonal degeneration,neuronal death and the consequent neurological disabilities(Franklin and Ffrench-Constant,2017).A main hallmark of MS is a preserved local neuroinflammatory *** is now acknowledged that this persistent inflammatory scenario is a central and common condition in almost all neurodegenerative pathologies(as in Parkinson’s and Alzheimer’s diseases,among others)controlling and modulating the regulatory responses of the system to the triggering *** the case of MS,this original insult corresponds to the loss of myelin(Chitnis and Weiner,2017;Franklin and Ffrench-Constant,2017).

关键词： Franklin representing degeneration