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Building Simulation 2022年第5期15卷 845-858页

作者： Fredrik Domhagen Paula Wahlgren carl-eric hagentoft Department for Architecture and Civil Engineering Division of Building TechnologyChalmers University of TechnologySE-41296GothenburgSweden

Some Swedish school buildings built in the 1960s and 1970s experience indoor air quality problems,where the contaminants are suspected to come from the crawl space underneath the *** poor indoor air quality causes discomfort among pupils and *** an exhaust fan to maintain a negative pressure difference in the crawl space relative to indoors or increasing the ventilation in the classroom are two examples of common measures taken to improve the indoor air ***,these measures are not always effective,and sometimes the school building has to be *** relation between pressure distribution,contaminant concentration in the classroom,outdoor temperature,wind,mechanical ventilation,and air leakage distribution is complex.A better understanding of these relations is crucial for making decisions on the most efficient measure to improve the indoor air *** this paper,a model for contaminant infiltration from the crawl space is used together with the Monte carlo method to study these *** are performed for several cases where different building shapes,building orientations,shielding conditions,and geographical locations are *** show,for example,that for a building with an imbalanced ventilation system,air is leaking from the crawl space to the classroom for the majority of cases and that concentration levels in the classroom are usually the highest during mild and calm days.

关键词： airtightness air permeability Monte carlo method infiltration model crawl space indoor air quality

Using transient plane source sensor for determination of thermal properties of vacuum insulation panels

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Frontiers of Architectural Research 2012年第4期1卷 334-340页

作者： Par Johansson Bijan Adl-Zarrabi carl-eric hagentoft Department of Civil ond Environmentol Engineering Cholmers University of Technology Gothenburg SE-412 96 Sweden

The energy use in buildings has to be decreased to reach the targets and regulations in the European Union. One way of reducing the energy demand is to use vacuum insulation panels （VIP） in the buitding envelope. To make sure the declared thermal properties of the VlP are valid for the mounted panels, in situ measurements are needed. The transient plane source （TPS） method allows fast measurement of the thermal properties of a variety of materials. However, the large anisotropy of the VIP makes it hard to interpret the temperature increase in the TPS sensor. This paper presents a comparison between an analytical solution, numerical simulations and TPS measurements of polystyrene and polystyrene with aluminum film. Polystyrene and aluminum were used instead of VIP to increase the number of setups. The numerical simulation model was validated by comparing the simulated temperature increase with an analytical solution for the polystyrene sample. The simulated temperature increase in the polystyrene sample after 40 s was 7.8% higher than the TPS measurements. For the case with polystyrene with aluminum film, the deviation was 5.7%. Losses in the wires of the TPS sensor, uncertainties regarding the material parameters and surface resistances could explain the deviations.

关键词： Thermal properties Transient planesource Vacuum insulationpanel AnaLytical solution Numerical simulation Measurement

Determination of specific heat capacity by transient plane source

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Frontiers of Architectural Research 2013年第4期2卷 476-482页

作者： Axel Berne Bijan Adl-Zarrabi carl-eric hagentoft Division of Building Technology Chulmers University of Technology Gothenburg SE-412 96 Sweden

A standard TPS measurement gives the thermal conductivity and thermal diffusivity of an isotropic material which in turn gives the heat capacity. The thermal properties of an anisotropic material can be measured if the heat capacity is known. A method for heat capacity measurement exists, where the TPS sensor is attached to a sample container which is surrounded by insulation. However, it＇s based on an assumption of negligible heat losses which leads to uncertainties in the results. From that position, this work aims to model the heat losses from the specific heat measurements with TPS. A new set-up is introduced, where the sensor with the container hangs freely in a steel tube to get more predictable heat losses. The results show that the measurements can be modelled as a network of lumps connected by conductances approximated as constant. Thereby, the conductances out from the system can be solved from a reference measurement and used as input for a model of a measurement with a sample. The model seems to underestimate the heat capacity, which might be a consequence of temperature dependent effects on the conductances from convection. The tube in the set-up could be evacuated to minimize those losses.

关键词： Specific heatcapacity Transient ptanesource TPS

A Tropical View on Landau-Ginzburg Models

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Acta Mathematica Sinica,English Series 2024年第1期40卷 329-382页

作者： Michael carl Max PUMPERLA Bernd SIEBERT Alfred-Delp-Str.2 73430 AalenGermany IU Internationale Hochschule Juri-Gagarin-Ring 15299084 ErfurtGermany AnyscaleInc.2080 Addison St Ste 7BerkeleyCA 94704USA Department of Mathematics The Univ.of Texas at Austin2515 SpeedwayAustinTX 78712USA

This paper,largely written in 2009/2010,fits Landau-Ginzburg models into the mirror symmetry program pursued by the last author jointly with Mark Gross since *** point of view transparently brings in tropical disks of Maslov index 2 via the notion of broken lines,previously introduced in two dimensions by Mark Gross in his study of mirror symmetry for P2.A ma jor insight is the equivalence of properness of the Landau-Ginzburg potential with smoothness of the anticanonical divisor on the mirror *** obtain proper superpotentials which agree on an open part with those classically known for toric *** include mirror LG models for non-singular and singular del Pezzo surfaces,Hirzebruch surfaces and some Fano threefolds.

关键词： Landau-Ginzburg model mirror symmetry tropical disk broken line wall structure scattering diagram Gross-Siebert program del Pezzo surface toric degeneration

Performance Assessment of the Overall Building Envelope Thermal Performance-Building Envelope Performance(BEP)Metric

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Journal of Civil Engineering and Architecture 2021年第6期15卷 300-317页

作者： Simon Pallin carl-eric hagentoft Antonio J.Aldykiewicz,Jr. Jason W.DeGraw Mahabir Bhandari Building Envelope&Urban Systems Research Group Oak Ridge National LaboratoryEnergy and Transportation Division1 Bethel Valley RdOak RidgeTN 37830USA Department of Architecture and Civil Engineering Division of Building TechnologyChalmers University of TechnologyChalmersplatsen 4Gothenburg 41296Sweden

Today,to describe the thermal performance of the building envelope and its components we use a variation of metrics;such as,R-value,ACH(air exchange rate per hour),SHGC(solar heat gain coefficient)of windows,U-factor *** of these performance indicators is meant to represent the overall thermal *** this paper,such a metric is introduced,the BEP(building envelope performance)*** the thermal resistance,typically expressed as an R-value,the BEP-value considers additional elements of heat transfer that affect the energy demand of the building because of exterior and interior(solar)thermal loads:conductive and radiant heat transfer,and air *** demonstrate BEP’s utility,validation studies were carried out by comparing the BEP-value to theoretical results using whole building energy simulation tools such as EnergyPlus and WUFI *** show that BEP calculations are comparable to calculations made using these simulation tools and that unlike other similar metrics,the BEP-value accounts for all heat transfer mechanisms that are relevant for the overall energy performance of the building *** BEP-value thus allows comparing envelopes of buildings with different use types in a fair and realistic manner.

关键词： Building enclosure energy R-value EUI(energy use intensity) airtightness building envelope campaign.

Physical activity with or without dietary intervention for the prevention of cardiovascular diseases

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Journal of Sport and Health Science 2024年第6期13卷 753-755页

作者： carl J.Lavie Salvatore Carbone Leandro Slipczuk The John Ochsner Heart and Vascular Institute Ochsner Clinical Schoolthe University of Queensland School of MedicineNew OrleansLA 70121USA Department of Kinesiology and Health Sciences College of Humanities and SciencesVirginia Commonwealth UniversityRichmondVA 23284USA Montefiore Health System/Albert Einstein College of Medicine BronxNY 10461USA

We and others have published extensively on the benefits of physical activity(PA),exercise training,and cardiorespiratory fitness(CRF)to decrease the prevalence of cardiovascular diseases(CVDs)and CVD and all-cause morbidity and mortality.^(1-5)Both PA and CRF are important;however,CRF,which is mostly obtained through PA,although there is a genetic component,seems to be even more important than PA for predicting prognosis.^(1,4-6)Certainly,the wealth of data from across the world has indicated that increasing PA to enhance CRF while mitigating sedentary behavior would go a long way to lessen the world-wide obesity epidemic and reduce CVD and all-cause mortality.

关键词： mortality prevention diseases

Taxonomy,distribution,and contemporary exposure of terrestrial mammals to floods and human pressure across different areas for biodiversity conservation in China

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Integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD eric I.AMECA MOE Key Laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： eric R.Hoglund Andrew R.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

Recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations

Larval development and voracity of Eupeodes americanus (Diptera: Syrphidae): comparison of the focal prey Aphis gossypi (Hemiptera: Aphididae) and the banker prey Rhopalosiphum padi (Hemiptera: Aphididae)

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Insect Science 2024年第2期31卷 575-586页

作者： Arlette Fauteux Antonio Onofre Soares eric Lucas Laboratoire de lutte biologique Departement des sciences biologiquesUniversite du Quebec a Montreal(UQAM)MontrealQuebecCanada Faculty of Science and Technology Center for Ecology Evolution and Environmental ChangesAzorean Biodiversity Group(cE3c-ABG)&CHANGE-Global Change and Sustainability InstitutePonta DelgadaPortugal

Unlike European species,the potential of Nearctic syrphids as biological control agents is still poorly ***,the American hoverfly,Eupeodes americanus(Wiedemann),has recently demonstrated promising traits as a biocontrol agent,notably against the foxglove aphid,Aulacorthum solani Kaltenbach,on *** present study aims to extend our knowledge of the American hoverfly by evaluating its potential as a biocontrol agent in a banker plant system against the melon aphid,Aphis gossypi Glover,in a greenhouse cucumber *** preimaginal development and voracity of *** were compared when preying upon the focal prey/pest(***)or the banker prey(bird cherry-oat aphid,Rhopalosiphum padi L.)by daily observations of larvae from egg to *** development time,survival rate,and occurrence of deformation were similar on both prey *** weight of third instar and pupae,however,was higher for larvae that fed on the banker *** ad libitum voracity of the syrphid larvae was generally very high and did not significantly differ between prey species,except for the third-instar larvae which consumed more focal *** suggest that a banker plant system involving the bird cherry-oat aphid may be a promising tactic for utilizing *** for melon aphid biocontrol.

关键词： american hoverfly banker plant system biological control bird cherry-oat aphid greenhouse cucumber melon aphid

Opto-fluidically multiplexed assembly and micro-robotics

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Light(Science & Applications) 2024年第3期13卷 544-554页

作者： Elena Erben Weida Liao Antonio Minopoli Nicola Maghelli eric Lauga Moritz Kreysing Max Planck Institute of Molecular Cell Biology and Genetics Dresden 01307Germany Center for Systems Biology Dresden 01307Germany Institute of Biological and Chemical Systems–Biological Information Processing.Karlsruhe Institute of Technology(KIT) Eggenstein-Leopoldshafen 76344Germany Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridge CB30WAUK

Techniques for high-definition micromanipulations,such as optical tweezers,hold substantial interest across a wide range of ***,their applicability remains constrained by material properties and laser *** while microfluidic manipulations have been suggested as an alternative,their inherent capabilities are limited and further hindered by practical challenges of implementation and *** we show that the iterative application of laser-induced,localized flow fields can be used for the relative positioning of multiple micro-particles,irrespectively of their material *** to the standing theoretical proposal,our method keeps particles mobile,and we show that their precision manipulation is non-linearly accelerated via the multiplexing of temperature stimuli below the heat diffusion *** resulting flow fields are topologically rich and mathematically *** represent unprecedented microfluidic control capabilities that are illustrated by the actuation of humanoid micro-robots with up to 30 degrees of freedom,whose motions are sufficiently well-defined to reliably communicate personal characteristics such as gender,happiness and *** results constitute high-definition micro-fluidic manipulations with transformative potential for assembly,micro-manufacturing,the life sciences,robotics and optohydraulically actuated micro-factories.

关键词： manipulation fluid assembly