Spatial Homogeneity Research Articles

Deforestation in Legal Amazon: A Panel Data Analysis of Potential Interferers

The knowledge on the significant factors that lead to environmental changes can be an attractive tool for directing priority actions of management, sustainability and impact minimization. In this regard, this work suggests the use of panel data analysis in environmental assessments, proposing a panel data regression model for the context of the Amazon forest, aiming to evaluate the role of primary activities over deforestation in Legal Amazon between 1988 and 2018. For this, the deforested areas in Legal Amazon were assessed regarding the potential explanatory variables: (i) area intended for soybean cultivation; (ii) area intended for palm oil cultivation; (iii) cattle ranching; and (iv) firewood and wood extraction. The model developed in this work evidenced cattle ranching and palm oil cultivation as significant factors for the increase of deforested areas, as well as the contribution of other factors besides primary activities in Amazon deforestation from 1988 to 2018. These results are in accordance with the literature, evidencing the applicability and assertiveness of the proposed method. This approach can help decision-makers of several other fields of environmental management. Additionally, this work also assessed the evolution of deforestation rates from 1988 to 2018, as well as possible regionalities and temporal trends in Legal Amazon deforestation. Statistically significant upward trends in deforestation rates in Amazonas, Mato Grosso, Pará, and Rondônia since 2012 were noticed. The spatial homogeneity in deforestation reinforces the need for effective oversight in Amazon.

Spatial distribution of plant diversity in shrub layer of Quercus variabilis plantation and its relationship with light environment

We analyzed the spatial heterogeneity of plant species diversity in shrub layers and its relationship with light environment in Quercus variabilis plantation and Q. variabilis-Platycladus orientali mixed forest, following the method of geostatistics. The results showed that plant species diversity indices (Shannon H, Simpson Ds, Margalef Ma) of shrub layers in Q. variabilis plantation were significantly lower than that in Q. variabilis-P. orientalis mixed forest. The variation ranges and spatial autocorrelation distances of plant species diversity index in Q. variabilis plantation were higher than that in Q. variabilis-P. orientalis mixed forest, with lower spatial homogeneity but stronger spatial dependence. The plant species diversity indices of H, Ds and Ma structural ratios of shrub layers in Q. variabilis pure forest were 44.2%-49.7%, with moderate spatial autocorrelation. The structure ratios of H, Ds and Ma in Q. variabilis-P. orientalis mixed forest were 1.5%-3.3%, with strong spatial autocorrelation. The spatial distribution of biodiversity showed obvious strip-like gradient trend in Q. variabilis plantation and patchy gradient change in Q. variabilis-P. orientalis mixed forest, suggesting that the spatial continuity of plant species of shrub layers was worse in Q. variabilis-P. orientalis mixed forest and that the spatial variation was stronger than that in Q. variabilis pure forest. Results of correlation analysis and stepwise regression analysis showed that the total light and plant canopy openness were the most significant factors affecting plant species diversity of shrub layers in both forest types. Light environment formed by plant canopy structure played a crucial part in maintaining plant diversity in shrub layer.

Backside-illuminated scientific CMOS detector for soft X-ray resonant scattering and ptychography.

The impressive progress in the performance of synchrotron radiation sources is nowadays driven by the so-called `ultimate storage ring' projects which promise an unprecedented improvement in brightness. Progress on the detector side has not always been at the same pace, especially as far as soft X-ray 2D detectors are concerned. While the most commonly used detectors are still based on microchannel plates or CCD technology, recent developments of CMOS (complementary metal oxide semiconductor)-type detectors will play an ever more important role as 2D detectors in the soft X-ray range. This paper describes the capabilities and performance of a camera equipped with a newly commercialized backside-illuminated scientific CMOS (sCMOS-BSI) sensor, integrated in a vacuum environment, for soft X-ray experiments at synchrotron sources. The 4 Mpixel sensor reaches a frame rate of up to 48 frames s-1 while matching the requirements for X-ray experiments in terms of high-intensity linearity (>98%), good spatial homogeneity (<1%), high charge capacity (up to 80 ke-), and low readout noise (down to 2 e- r.m.s.) and dark current (3 e- per second per pixel). Performance evaluations in the soft X-ray range have been carried out at the METROLOGIE beamline of the SOLEIL synchrotron. The quantum efficiency, spatial resolution (24 line-pairs mm-1), energy resolution (<100 eV) and radiation damage versus the X-ray dose (<600 Gy) have been measured in the energy range from 40 to 2000 eV. In order to illustrate the capabilities of this new sCMOS-BSI sensor, several experiments have been performed at the SEXTANTS and HERMES soft X-ray beamlines of the SOLEIL synchrotron: acquisition of a coherent diffraction pattern from a pinhole at 186 eV, a scattering experiment from a nanostructured Co/Cu multilayer at 767 eV and ptychographic imaging in transmission at 706 eV.

Does spatial homogeneity ultimately prevail in nutrient taxis systems? A paradigm for structure support by rapid diffusion decay in an autonomous parabolic flow

This work is concerned with the doubly degenerate cross-diffusion system (*) { u t = ( u v u x ) x − ( u 2 v v x ) x + u v , v t = v x x − u v , \begin{equation}\tag {*} \left \{ \begin {array}{l} u_t = (uvu_x)_x - (u^2 vv_x)_x + uv, \\[1mm] v_t = v_{xx}-uv, \end{array} \right . \end{equation} that has been proposed as a model for experimentally observable quite complex pattern formation phenomena in bacterial populations. It is shown that for any initial data satisfying adequate regularity and positivity assumptions, a no-flux initial-boundary value problem for the above in a bounded real interval possesses a global weak solution which is continuous in its first and essentially smooth in its second component. This solution is seen to asymptotically stabilize in the sense that (**) u ( ⋅ , t ) → u ∞ and v ( ⋅ , t ) → 0 as t → ∞ \begin{equation}\tag {**} u(\cdot ,t) \to u_\infty \quad \text {and} \quad v(\cdot ,t)\to 0 \qquad \text {as } t\to \infty \end{equation} with some nonnegative u ∞ ∈ C 0 ( Ω ¯ ) u_\infty \in C^0(\overline {\Omega }) which can be obtained as the evaluation of a weak solution z ∈ C 0 ( Ω ¯ × [ 0 , 1 ] ) z\in C^0(\overline {\Omega }\times [0,1]) to a porous medium-type parabolic problem at the finite time 1 1 . It is, moreover, revealed that for each suitably regular nonnegative function u ⋆ u_\star on Ω \Omega , the pair ( u ⋆ , 0 ) (u_\star ,0) , formally constituting an equilibrium of \eqref{01}, is stable in an appropriate sense. This finally implies a sufficient criterion for the limit u ∞ u_\infty in \eqref{02} to be spatially heterogeneous. The latter properties are in sharp contrast to known asymptotic features of corresponding nutrient taxis systems involving linear nondegenerate diffusion, as for which the literature appears to exclusively provide results on solutions which approach spatially constant states in the large time limit.

Spatial dynamics and optimization method for a network propagation model in a shifting environment

<p style='text-indent:20px;'>In this paper, a reaction-diffusion <inline-formula><tex-math id="M1">\begin{document}$ ISCT $\end{document}</tex-math></inline-formula> rumor propagation model with general incidence rate is proposed in a spatially heterogeneous environment. We first summarize the well-posedness of global solutions. Then the basic reproduction number <inline-formula><tex-math id="M2">\begin{document}$ \mathcal{R}_0 $\end{document}</tex-math></inline-formula> is introduced for the model which contains the spatial homogeneity as a special case. The threshold-type dynamics are also established in terms of <inline-formula><tex-math id="M3">\begin{document}$ \mathcal{R}_0 $\end{document}</tex-math></inline-formula>, including the global asymptotic stability of the rumor-free steady state and the uniform persistence of all positive solutions. Furthermore, by applying a controller to this model, we investigate the optimal control problem. Employing the operator semigroup theory, we prove the existence, uniqueness and some estimates of the positive strong solution to the controlled system. Subsequently, the existence of the optimal control strategy is established with the aid of minimal sequence techniques and the first order necessary optimality conditions for the optimal control is deduced. Finally, some numerical simulations are performed to validate the main analysis. The results of our study can theoretically promote the regulation of rumor propagation on the Internet.

Spatial and temporal variability in discharge and nitrate in Iowa subsurface drains.

Agricultural subsurface drainage can be an important conduit of nitrate from agricultural fields to streams. This study focused on understanding the variability in nitrate concentrations and loads, exported by subsurface drains, into a small, north-central Iowa stream. Ninety-three subsurface drains in this watershed were sampled up to 5 times between 2006 and 2008. Additionally, 2 subsurface drains and the stream draining the study area (South Fork Iowa River near Blairsburg, IA, USA) were sampled frequently during the growing seasons in 2007 and 2008. Spatial variability analysis revealed no distinct spatial pattern in nitrate concentrations. The median nitrate concentrations were not significantly different when the drain outlets were characterized by diameter (17-23 cm, 27-48 cm, 60-108 cm). The eight large subsurface drains (part of the public drainage network) had less variability in nitrate concentration than the smaller drain sizes and generally contributed 70-87% of the total water and nitrate loads exported by subsurface drains to the stream. During high-discharge events, the medium-sized (27-48 cm) subsurface drains discharging to the stream became more important by contributing a higher discharge and nitrate load. The temporal variability examined in this study found that discharge and nitrate loads were influenced by the amount of precipitation that had occurred over the previous months. This paper demonstrates the spatial and within-season homogeneity of nitrate delivery to a stream from an intensely agricultural landscape that has subsurface drainage.

Beam characterization at NSRL for radiobiological experiments—phase 1

An experimental campaign was carried out at the NASA Space Radiation Laboratory to perform an additional, independent dosimetric characterization of the beams of protons, helium and carbon ions for radiobiological experiments. The campaign was undertaken by the request and with the support from the National Cancer Institute, U.S. In this initial phase, the goals were to obtain a first assessment of the dosimetric reproducibility of the beam control system, including analysis of spatial homogeneity and evaluation of ion beam contamination. They should facilitate the design of further experimental campaigns for beam characterization for radiobiological experiments. Measurements included reference dosimetry with comparison of in-house and external ionization chambers and electrometers, lateral-dose profile measurements in air, depth-dose profile in a water tank, evaluation of water equivalent thickness of a HDPE binary range shifter and estimation of impurities of the investigated helium-ion beam. The experiments and results are presented.

Global-scale albedo and spectro-photometric properties of Ryugu from NIRS3/Hayabusa2, implications for the composition of Ryugu and the representativity of the returned samples

The type C asteroid Ryugu has been visited by the JAXA Hayabusa2 mission, a first for a primitive asteroid in the Solar System exploration. Samples have been collected at its surface by the spacecraft and are now on their way back to Earth. The surface of Ryugu has also been observed both in the visible and infrared wavelengths with the objective of characterizing its properties at a global scale. Here, we report on the albedo and spectro-photometric properties of Ryugu as derived from the NIRS3 IR spectrometer. Thanks to an innovative technique based on a Bayesian approach, we retrieved the Hapke photometric parameters from multi-geometric NIRS3 observations over the NIR spectral range and different areas of Ryugu, including the first collection site. Results reveal an overall spatial homogeneity of the photometric parameters, though some small variations can be highlighted. A new photometric correction was derived and applied to NIRS3 data. Reflectance spatial heterogeneity was quantitatively investigated, in particular by deriving and mapping the single scattering albedo (SSA) at various spatial scales. This parameter could be derived with confidence on about one fourth of Ryugu’s surface, especially around the equatorial region and the southern middle latitudes. Although Ryugu is to first order homogeneous with a typical SSA of 0.045–0.050, we demonstrate with a local-scale photometric correction (1) the presence of a large “bright” area between ∼190∘E and ∼290∘E longitude around the equator and the southern middle latitudes, and (2) the presence of darker areas with a clear connection to geomorphological features. We show here that these darker regions tend to have a slightly deeper 2.72μm feature, at least compared to the surrounding areas, which can be explained by an enrichment of the top-surface in dark fines coupled to hydrated phases. Some spatial variability observed in the coupling between the SSA at 1.89μm and the 2.72μm absorption feature also suggests that Ryugu exhibits some (slight) heterogeneity in its building blocks.

High-Throughput Growth of Wafer-Scale Monolayer Transition Metal Dichalcogenide via Vertical Ostwald Ripening.

For practical device applications, monolayer transition metal dichalcogenide (TMD) films must meet key industry needs for batch processing, including the high-throughput, large-scale production of high-quality, spatially uniform materials, and reliable integration into devices. Here, high-throughput growth, completed in 12 min, of 6-inch wafer-scale monolayer MoS2 and WS2 is reported, which is directly compatible with scalable batch processing and device integration. Specifically, a pulsed metal-organic chemical vapor deposition process is developed, where periodic interruption of the precursor supply drives vertical Ostwald ripening, which prevents secondary nucleation despite high precursor concentrations. The as-grown TMD films show excellent spatial homogeneity and well-stitched grain boundaries, enabling facile transfer to various target substrates without degradation. Using these films, batch fabrication of high-performance field-effect transistor (FET) arrays in wafer-scale is demonstrated, and the FETs show remarkable uniformity. The high-throughput production and wafer-scale automatable transfer will facilitate the integration of TMDs into Si-complementary metal-oxide-semiconductor platforms.

Large-Scale Flexible Surface-Enhanced Raman Scattering (SERS) Sensors with High Stability and Signal Homogeneity

Flexible surface-enhanced Raman scattering (SERS) sensors have attracted great attention as a portable and low-cost technique for chemical and bio-detecting. However, flexible SERS sensors tend to suffer low signal spatial homogeneity due to their uneven active plasmonic nanostructures (hot-spots) distribution, and quick degradation of SERS sensors' sensitivity due to low adhesion of hot-spots and flexible substrates during fast sampling. Herein, a large area (20×20 cm2) polyimide (PI) based SERS sensor is exploited for trace detection with high signal homogeneity and stability. The SERS sensor is constructed from PI through in situ growth of silver and gold core-shell nanoparticles (Ag@Au NPs) based on chemical reduction and galvanic replacement process. Benefiting from the abundant carboxyl groups on the surface cleavaged PI, densely and uniformly distributed Ag@Au NPs are successfully prepared on the film under ambient conditions. The high Raman enhancement factor (up to 1.07 × 107) and down detection capability of nanomolar (10-9 M) detection limits are obtained for this flexible SERS sensor. The uniform Raman signals in the random region show well signal homogeneity with a low variation of 8.7%. Moreover, the flexible SERS sensor exhibited superior efficiency durability after storage 30 days even after mechanical stimuli (bending or torsion) 500 cycles. The pesticide thiram (TMTD) residue has been rapidly traced by direct sampling from the apple surface, and a sensitivity of 10 ng/cm2 for TMTD was achieved. These findings show that the PI-based SERS sensor is a very strong candidate for broad and simple utilization of flexible SERS for both laboratory and commercial applications in chemical and biomolecule detections.

Anisotropic functional deconvolution for the irregular design: A minimax study

Anisotropic functional deconvolution model is investigated in the bivariate case when the design points ti , and xl , are irregular and follow known densities h 1, h 2, respectively. In particular, we focus on the case when the densities h 1 and h 2 have singularities, but and are still integrable on [0, 1]. We construct an adaptive wavelet estimator that attains asymptotically near-optimal convergence rates in a wide range of Besov balls. The convergence rates are completely new and depend on a balance between the smoothness and the spatial homogeneity of the unknown function f, the degree of ill-posed-ness of the convolution operator and the degrees of spatial irregularity associated with h 1 and h 2. Nevertheless, the spatial irregularity affects convergence rates only when f is spatially inhomogeneous in either direction.

Exploring the potentiality of standard sirens to probe cosmic opacity at high redshifts

In this work, using the Gaussian process, we explore the potentiality of future gravitational wave (GW) measurements to probe cosmic opacity at high redshifts through comparing its opacity-free luminosity distance (LD) with the opacity-dependent one from the combination of Type Ia supernovae (SNIa) and gamma-ray bursts (GRBs). The GW data, SNIa and GRB data are simulated from the measurements of the future Einstein Telescope, the actual Pantheon compilation and the latest observation of GRBs compiled by Amati et al, respectively. A nonparametric method is proposed to probe the spatial homogeneity of cosmic transparency at high redshift by comparing the LD reconstructed from the GW data with that reconstructed from the Pantheon and GRB data. In addition, the cosmic opacity is tested by using the parametrization for the optical depth, and the results show that the constraints on cosmic opacity are more stringent than the previous ones. It shows that the future GW measurements may be used as an important tool to probe the cosmic opacity in the high redshift region.

Chemical vapor deposition synthesized monolayer MoS2 for Q-switching pulse generation in the 2 µm spectral region

We demonstrate a monolayer MoS2-based saturable absorber (SA) synthesized by chemical vapor deposition (CVD). The as-grown SA has high spatial homogeneity and shows excellent saturable absorption properties in the 2 µm wavelength region. A higher modulation depth of 21.3% and lower saturation intensity of 0.47 MW/cm2 are achieved compared with those of other documented MoS2 SAs to date. When applying the MoS2 SA to a Tm:YAG ceramic laser, we observe a Q-switched pulse train with a shortest pulse duration of 388.0 ns under a pulse repetition rate of 82 kHz, which corresponds to a single pulse energy of 5.4 uJ and a peak power of 14 W. We believe that CVD constitutes an effective method towards high-quality MoS2 saturable absorbers that possess remarkable application potential in the 2 µm wavelength region.

Tomography of double-pulse laser-induced plasmas in the orthogonal geometry

The temporal evolution of laser-induced plasmas is studied in the orthogonal double-pulse arrangement. Both the pre-ablation mode (an air spark is induced above the sample surface prior to the ablation pulse) and the re-heating mode (additional energy is delivered into the plasma created by the ablation pulse) is considered. The plasmas are investigated in terms of the temporal evolution of their electron density, temperature, and volume. The plasma volumes are determined using a time-resolved tomography technique based on the Radon transformation. The reconstruction is carried out for both white-light and band-pass filtered emissivities. The white-light reconstruction corresponds to the overall size of the plasmas. On the other hand, the band-pass emissivity reconstruction shows the distribution of the atomic sample species (Cu I). Moreover, through spectrally resolved tomographic reconstruction, the spatial homogeneity of the electron density and temperature of the plasmas is also investigated at various horizontal slices of the plasmas. Our results show that the pre-ablation geometry yields a more temporally stable and spatially uniform plasma, which could be beneficial for calibration-free laser-induced breakdown spectroscopy (LIBS) approaches. On the contrary, the plasma generated in the re-heating geometry exhibits significant variations in electron density and temperature along its vertical axis. Overall, our results shed further light on the mechanisms involved in the LIBS signal enhancement using double-pulse ablation.

A dual symmetric Gauss-Seidel alternating direction method of multipliers for hyperspectral sparse unmixing

Since sparse unmixing has emerged as a promising approach to hyperspectral unmixing, some spatial-contextual information in the hyperspectral images has been exploited to improve the performance of the unmixing recently. The total variation (TV) has been widely used to promote the spatial homogeneity as well as the smoothness between adjacent pixels. However, the computation task for hyperspectral sparse unmixing with a TV regularization term is heavy. Besides, the convergence of the primal alternating direction method of multipliers (ADMM) for the hyperspectral sparse unmixing with a TV regularization term has not been explained in detail. In this paper, we design an efficient and convergent dual symmetric Gauss-Seidel ADMM (sGS-ADMM) for hyperspectral sparse unmixing with a TV regularization term. We also present the global convergence and local linear convergence rate analysis for this algorithm. As demonstrated in numerical experiments, our algorithm can obviously improve the efficiency of the unmixing compared with the state-of-the-art algorithm. More importantly, we can obtain images with higher quality.

Theoretical Kinetics Investigation of Krypton Dielectric Barrier Discharge for UV Lamp

This work presents an electric and kinetic study of homogeneous dielectric barrier discharge (DBD) in pure krypton (Kr). The electrical characterization and kinetic analyses of the DBD in Kr are performed. The plasma formation in DBD, excited by sinusoidal voltage at high pressure, was studied. The discharge development, with homogeneous model approach and using extended kinetic scheme, is simulated. The study is based on a spatial homogeneity model including the plasma chemistry, the electrical circuit and the Boltzmann equations’. The temporal variations of discharge voltage, dielectrics voltage, discharge current, electric field and species concentrations are calculated. The plasma kinetics is discussed with the aim to finding the optimal efficiency. The photon generation, under typical operating conditions, was investigated and discussed. The effect of some parameters on the excilamp like pressure, applied voltage, and frequency are investigated in order to identify the optimal parameters for maximum luminous efficiency in the UV range.

Reactivity and Stability of Ultrathin VOx Films on Pt(111) in Catalytic Methanol Oxidation

The growth of ultrathin layers of VOx (< 12 monolayers) on Pt(111) and the activity of these layers in catalytic methanol oxidation at 10−4 mbar have been studied with low-energy electron diffraction, Auger electron spectroscopy, rate measurements, and with photoemission electron microscopy. Reactive deposition of V in O2 at 670 K obeys a Stranski–Krastanov growth mode with a (√3 × √3)R30° structure representing the limiting case for epitaxial growth of 3D-VOx. The activity of VOx/Pt(111) in catalytic methanol oxidation is very low and no redistribution dynamics is observed lifting the initial spatial homogeneity of the VOx layer. Under reaction conditions, part of the surface vanadium diffuses into the Pt subsurface region. Exposure to O2 causes part of the V to diffuse back to the surface, but only up to one monolayer of VOx can be stabilized in this way at 10−4 mbar.

Developing improved methods for identifying the cost-efficient abatement set in coastal water quality protection

Eutrophication of coastal waters is a recognised problem in estuaries around the globe. To analyse cross-boundary water quality management, such as protection of the Baltic Sea, economic nutrient abatement models commonly operate on a large scale, grouping river systems to large catchment areas. Theoretical deliberation suggests that modelling abatement in such a way removes the opportunity of targeting measures to the most vulnerable regions within the catchment, while overestimating the capacity of abatement measures in the upstream areas. However, the implications on designing environmental policy depend on catchment characteristics and the stringency of the abatement targets. In this study a model of the catchment area is built with zones that are an increasing distance away from the coast to show what kind of bias in the optimal abatement set is caused by the assumption of spatial homogeneity. By solving the model with and without the zones for good ecological status at the South-West coast of Sweden, it is shown that while assuming homogeneity prevents from perceiving the abatement measures where they would be the most effective, it also leads to ignoring spatial limitations that are more relevant to a subset of abatement measures, such as the wetlands and buffer zones. Following from the relatively large nitrogen abatement targets, the overall effect of assuming catchment homogeneity is to underestimate the abatement costs and to overestimate the potential of wetlands to reduce nitrogen.

Solar Assisted Dehydrator for Decentralized Controlled and Homogeneous Multi-Product Drying

Abstract Batch type food dryers are common for drying agricultural produce due to simple in design, but they are prone to nonuniform drying and significant heat cost exclusively if they fall in the medium to large size range. The current study illustrates a solar hybrid food dryer using a gas burner and solar collector (evacuated tube collector, ETC) as heating source along with an inline perforation inside the drying chamber to obtain spatial drying homogeneity. Air distribution was assessed through three-dimensional simulation using computational fluid dynamics (CFD) analysis. Performance trials were conducted under three heating options (ETC, gas, and dual) using green chilies at 60 °C. Throughout drying chamber, under all heating modes, the average difference in drying rates ranged from 0.61 to 1.30 kg water/kg dry matter, demonstrating homogeneous drying. Simulated and experimental results of air distribution were found to be in agreement with each other. Using three options for thermal heating (ETC, gas, and dual) and an overall 58% efficiency for evacuated tube collector, the specific energy for moisture evaporation was found to be 4.5–5.7 MJ/kg and specific product energy 19.2–24.9 MJ/kg. In case of dual heating option, the energy supplied by solar and gas sources for a 20 hours period was 50.64% (160.22 MJ) and 49.35% (156.13 MJ), respectively. Compared with dual heating option, energy cost can be reduced by 68% if only solar energy is used as a heating option but with a protracted drying time.

On the experimental investigation of novel low-momentum ventilation concepts for cooling operation in a train compartment

We report on an experimental investigation of novel, low-momentum ventilation concepts for a train compartment. The concepts were analyzed with regard to thermal comfort, spatial homogeneity, heat removal efficiency and their capability of integration. The studies were conducted using thermal manikins in a generic train cabin, that is, the lower level of a double-deck high-speed train ”DLR’s Next Generation Train - NGT”. Various ventilation concepts comprising state of the art micro-jet ventilation (MJV) as well as novel low-momentum ventilation concepts were investigated. The novel concepts are floor-based cabin displacement ventilation (CDV), low-momentum ceiling-based ventilation (LMCV), a hybrid (HV) combination of CDV and LMCV as well as hatrack-integrated low-momentum ventilation (HLMV). The results proved that all investigated concepts have advantages and disadvantages. The recorded mean air velocities of all concepts are well below the limiting values defined in the standard for long-distance rolling stock. However, the analysis of the instantaneous velocities revealed that classical mixing ventilation exceeded the thresholds from time to time. Regarding the capability of integration, the floor-based CDV and the hatrack-integrated concept turned out to be advantageous since no space in the aisle zone is required. For the HLMV concept, which is fully integrated in the hatracks, stronger horizontal temperature fluctuations were recorded highlighting the need to optimize the HLMV air outlets. In the current stage, LMCV and the hybrid approach were found to be the best concepts. They were not rated as critical in any of the considered categories.