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1
Fulthorpe, Roberta R., and J. E. Paloheimo. "Hypolimnetic Oxygen Consumption in Small Lakes." Canadian Journal of Fisheries and Aquatic Sciences 42, no. 9 (1985): 1493–500. http://dx.doi.org/10.1139/f85-187.
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The hypolimnetic oxygen consumption rates of 28 Ontario lakes were calculated and compared with lake morphology, chemical concentrations, and productivity measures. In most cases, hypolimnia had upper zones where average light intensities were greater than 1% of surface light. In these layers, oxygen dynamics were highly variable from year to year and production rather than consumption was common. The ratio of areal oxygen consumption below the 1% light level to planktonic production corrected for retention was studied as a measure of percent available material decomposed. Using stepwise multiple regressions, we found this parameter to be related to mean thickness of the hypolimnion, lake organic carbon, and iron concentrations. The range of lake productivities in the data set was small and did not explain a significant portion of the variance in areal hypolimnetic depletion rates.
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Kiss, Ervin, and Péter Volford. "Depth and Areal Distribution of Cs-137 in the Soil of a Small Water Catchment in the Sopron Mountains." Acta Silvatica et Lignaria Hungarica 9, no. 1 (2013): 147–59. http://dx.doi.org/10.2478/aslh-2013-0012.
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Abstract - The study presents the depth and areal distribution of Cs-137 activity concentration in the forest soils of Farkas Trench, a small water catchment in the Sopron Mountains, in 2001 and 2010, moreover the possible reason of the alteration in activity concentration. The Cs-137 activity values were measured in 30 plots in 2001, and in 5 in 2010. In 2001, the depth distribution of Cs-137 activity concentration in the measurement plots was shaped in accordance with a decreasing exponential function. It appeared in the 2010 data that the highest Cs-137 activity concentration had shifted lower from the top layers, and the depth distribution changed along an increasing or a stagnating function until a depth of 4 to 6 cm (in function of slope inclination), then along a decreasing function. In 2001, activity concentration in the surface soil layers (0 - 2 cm) altered between 15 and 609 Bq/kg, whereas in 2010 between 26 and 72 Bq/kg. A correlation was found between activity concentration in the surface soil layer and slope inclination. It was concluded that one of the main reasons for differences in distribution of Cs-137 activity concentration was the differing extent of soil movement.
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El Messiry, Magdi, and Nermin Fadel. "Enhancing the spreading dynamics of oil drops over nanofiber substrates." Textile Research Journal 90, no. 2 (2019): 213–26. http://dx.doi.org/10.1177/0040517519866947.
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The spreading dynamics of small oil drops over nanofiber layers has been investigated to improve the oil spill management process. Although liquid transport studies have been used to compare different substrates, the actual effect of the fibrous substrate structure has not been precisely investigated. Nanofiber substrate structures consist of micro- and nanocapillaries that vary in diameter and length and are interconnected in a complex manner. Migration of a liquid from one layer to another as well as on the same layer is an important part of the sorption process in nanofiber substrate structures. In this work, the problem under investigation provides spreading small oil drops over a thin porous layer nanofiber until saturation. An experimental evolution describing the drop spreading has been deduced, which shows the speed of spread of the oil drop is significantly affected by the substrate areal weight. The oil drop area over a dry porous layer seems to be caused by the interchange of two spreading velocities, one over the layers and the other penetration of the oil drop through the pores of the substrate. The higher the oil spreading speed, the lower the permeation of the oil into the porous nanofiber substrate and vice versa. To increase the absorption of the nanofiber substrate, adding a nonwoven thin film to cover the nanofiber layers was studied. It was revealed that the presence of such film significantly accelerates the oil-drop spreading speed by up to 300% and reduces the overall time of the oil drop's life.
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Morey, A. E., C. Goldfinger, C. E. Briles, D. G. Gavin, D. Colombaroli, and J. E. Kusler. "Are great Cascadia earthquakes recorded in the sedimentary records from small forearc lakes?" Natural Hazards and Earth System Sciences 13, no. 10 (2013): 2441–63. http://dx.doi.org/10.5194/nhess-13-2441-2013.
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Abstract. Here we investigate sedimentary records from four small inland lakes located in the southern Cascadia forearc region for evidence of earthquakes. Three of these lakes are in the Klamath Mountains near the Oregon–California border, and one is in the central Oregon Coast range. The sedimentary sequences recovered from these lakes are composed of normal lake sediment interbedded with disturbance event layers. The thickest of these layers are graded, and appear to be turbidites or linked debrites (turbidites with a basal debris-flow deposit), suggesting rapid deposition. Variations in particle size and organic content of these layers are reflected in the density and magnetic susceptibility data. The frequency and timing of these events, based on radiocarbon ages from detrital organics, is similar to the offshore seismogenic turbidite record from trench and slope basin cores along the Cascadia margin. Stratigraphic correlation of these anomalous deposits based on radiocarbon ages, down-core density, and magnetic susceptibility data between lake and offshore records suggest synchronous triggering. The areal extent and multiple depositional environments over which these events appear to correlate suggest that these deposits were most likely caused by shaking during great Cascadia earthquakes.
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Sakamoto, Shuichi, Ren Saito, Keisuke Jindai, and Koki Ikeda. "Characteristics of powders that cause sound absorption in the low frequency range due to longitudinal vibration in lightweight and fine powders." INTER-NOISE and NOISE-CON Congress and Conference Proceedings 265, no. 3 (2023): 4876–81. http://dx.doi.org/10.3397/in_2022_0704.
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In this paper, focus is placed on "lightweight and fine powders" which have small particle size and bulk density and exhibit unique sound absorption characteristics at low frequencies due to longitudinal vibration of powder particles. Theoretical analysis of the sound absorption coefficient of powder layers requires the peak frequency of sound absorption measured experimentally. In this study, we clarified the relationship between powder properties and sound absorption characteristics, and predicted the sound absorption coefficient of the powder layer from the experimental equation based on the accumulated data. This made it possible to classify powders in which sound absorption due to longitudinal vibration occurs based on the relationship between the "areal density per particle layer," which is indicated by "particle size multiplied by bulk density," and the peak sound absorption value. Moreover, from the plot of "areal density per particle layer" and "first-order sound absorption peak frequency from experiment," the experimental formula for the first-order sound absorption peak frequency was regressively obtained. By using the experimental equation obtained in this study, it was possible to show how to estimate the sound absorption coefficient from the properties of each powder alone.
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Paranoan, Ria Rachel. "Komposisi Fraksi Pasir dan Sifat Kimia Tanah Pada Areal Revegetasi Lahan Bekas Tambang Batubara." Agrifarm : Jurnal Ilmu Pertanian 8, no. 2 (2020): 46. http://dx.doi.org/10.24903/ajip.v8i2.788.
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The purpose of this research were to determine the composition of sand fraction and chemical properties at revegetation area. The research was conducted from April to October 2019 . The mineralogical Compositions of sand fraction were analyzed using a Polarizing Microscope (PM) at the laboratory of Mineral BB Litbang SDLP, Bogor. The results showed that the composition of sand fractionof soil at revegetation area was dominatd by quartz,with small amounts of opaque, zircon,weathered mineral, rock fragment, and tourmaline.Chemical properties indicated that the soil at revegetation area showed pH from 6,05 to 6,49, had low content of cation exchange capacity in the whole layers, very high content of base saturation, very low to low organic carbon. Exchangeable K and Na are low in the whole layers, the moderate content of potential potassium. Both exchangeable Ca and Mg were lot to moderate. Potentioal P content in soil varies from moderate to high.Soil management in revegetation area should be focused on Maintaining soil fertility through application of liming, and fertilizers
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Schäfer, K., R. H. Grant, S. Emeis, A. Raabe, C. von der Heide, and H. P. Schmid. "Areal-averaged trace gas emission rates from long-range open-path measurements in stable boundary layer conditions." Atmospheric Measurement Techniques Discussions 5, no. 1 (2012): 1459–96. http://dx.doi.org/10.5194/amtd-5-1459-2012.
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Abstract. Measurements of land-surface emission rates of greenhouse and other gases at large spatial scales (10 000 m2) are needed to assess the spatial distribution of emissions. This can be more readily done using spatial-integrating micro-meteorological methods than the widely-utilized small chamber measurements. Several micro-meteorological flux-gradient methods utilizing a non-intrusive path-averaging measurement method were evaluated for determining land-surface emission rates of trace gases under stable boundary layers. Successful application of a flux-gradient method requires confidence in the gradients of trace gas concentration and wind and in the applicability of boundary-layer turbulence theory. While there is relatively high confidence in flux measurements made under unstable atmospheres with mean winds greater than 1 m s−1, there is greater uncertainty in flux measurements made under free convective or stable conditions. The study involved quality-assured determinations of fluxes under low wind, stable or night-time atmospheric conditions when the continuous "steady-state" turbulence of the surface boundary layer breaks down and the layer has intermittent turbulence. Results indicate that the Monin-Obukhov similarity theory (MOST) flux-gradient methods that assume a log-linear profile of the wind speed and concentration gradient incorrectly determine vertical profiles and thus fluxes in the stable boundary layer.
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Mohammed, Mohaned, and Doo-Man Chun. "Electrochemical Performance of Few-Layer Graphene Nano-Flake Supercapacitors Prepared by the Vacuum Kinetic Spray Method." Coatings 8, no. 9 (2018): 302. http://dx.doi.org/10.3390/coatings8090302.
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A few-layer graphene nano-flake thin film was prepared by an affordable vacuum kinetic spray method at room temperature and modest low vacuum conditions. In this economical approach, graphite microparticles, a few layers thick, are deposited on a stainless-steel substrate to form few-layer graphene nano-flakes using a nanoparticle deposition system (NPDS). The NPDS allows for a large area deposition at a low cost and can deposit various metal oxides at room temperature and low vacuum conditions. The morphology and structure of the deposited thin films are alterable by changing the scan speed of the deposition. These changes were verified by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy. The electrochemical performances of the supercapacitors, fabricated using the deposited films and H3PO4–PVA gel electrolytes with different concentrations, were measured using a 2-electrode cell. The electrochemical performance was evaluated by cyclic voltammetry, galvanostatic Charge–discharge, and electrochemical impedance spectroscopy. The proposed affordable fabricated supercapacitors show a high areal capacitance and a small equivalent series resistance.
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Pandit, Sanchaya, Mao Sui, Sundar Kunwar, Puran Pandey, Sandesh Pant, and Jihoon Lee. "Fabrication of Various Plasmonic Pt Nanostructures via Indium Assisted Solid-State Dewetting: From Small Nanoparticles to Widely Connected Networks." Nanomaterials 9, no. 6 (2019): 831. http://dx.doi.org/10.3390/nano9060831.
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In this paper, the modified solid-state dewetting (MSSD) of well-defined and various uniform Pt nanostructures is demonstrated by the auxiliary diffusion enhancement. The MSSD utilizes the introduction of metallic indium (In) layers with high diffusivity in between sapphire and platinum (Pt) layer, through which the global diffusion and dewetting of metallic atoms can be significantly enhanced. Subsequently, the In atoms can be sublimated from the NP matrix, resulting in the formation of pure Pt NPs. By the systematic control of In and Pt bi-layer thickness, various areal density, size and configuration of Pt NPs are demonstrated. The In2 nm/Pt2 nm bilayers establish very small and highly dense NPs throughout the temperature range due to the early maturation of growth. Intermediate size of NPs is demonstrated with the In45 nm/Pt15 nm bilayers with the much improved interparticle spacings by annealing between 650 and 900 °C for 450 s. Finally, the In30 nm/Pt30 nm bilayers demonstrate the widely connected network-like nanostructures. In addition, the finite difference time domain (FDTD) simulation is employed to exploit the local electric field distributions at resonance wavelengths. The dewetting characteristics of In/Pt bilayers is systematically controlled by the modifications of layer thickness and annealing temperature and is systematically described based on the diffusion of atoms, Rayleigh instability and surface energy minimization mechanism. The optical properties demonstrate dynamic and widely tunable localized surface plasmon resonance (LSPR) responses depending upon the various surface morphologies of Pt nanostructures.
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Steele, G. E., and R. E. Weller. "Qualitative and quantitative features of axons projecting from caudal to rostral inferior temporal cortex of squirrel monkeys." Visual Neuroscience 12, no. 4 (1995): 701–22. http://dx.doi.org/10.1017/s0952523800008981.
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AbstractOn the basis of cortical and subcortical connections and architectonics, inferior temporal (IT) cortex of squirrel monkeys consists of a caudal region, ITC, with dorsal (ITCd) and ventral (ITCv) subdivisions; a rostral region, ITR; and possibly a third region intermediate to ITC and ITR, IT1 (Weller & Steele, 1992; Steele & Weller, 1993). The present study qualitatively and quantitatively examined the terminal arborizations of 26 axons in ITR and IT1 labeled by injections of biocytin or, in one case, horseradish peroxidase, in ITCv. The majority of axons gave rise to a single terminal arbor, with a small number branching into two overlapping or nearby arbors. Presumptive terminal specializations consisted of rounded, bead-like swellings, most often located en passant. All axons terminated in layer 4 of cortex, and most had additional terminations in layers 3 and 5. The total extent of each axon's terminal arbor was 125–750 μm dorsoventrally (mean = 360.6 μm) and 150–725 μm anteroposteriorly (mean = 328.1 μm; all values uncorrected for shrinkage). In most axons, especially those with larger terminal fields, boutons were not uniformly distributed, but formed 2–4 clumps (mean = 2.2), with a mean width of 149 μm, separated by narrower regions of fewer boutons. Based on a cluster analysis of characteristics of the 26 axons, axons projecting from caudal (ITCv) to rostral (ITR or IT1) IT cortex of squirrel monkeys comprised three groups that we called Type I, Type II, and Type III. Type I axons, the smallest in areal extent of terminal arbor, terminated predominantly in dorsal ITR. Type III axons, largest in areal extent, and Type II axons, intermediate in areal extent, terminated in ventral ITR and throughout IT1. The three classes of axons may correspond to different types of visual information entering rostral IT cortex. The clumping of boutons suggests that individual axons terminate in limited patches within their terminal fields.
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Korolev, Eduard, Aleksey Eskin, Alsu Khuzina, Albert Korolev, and Enza Barieva. "The prospects of oil deposits of the Vereyian horizon of the marginal part of the Melekess-Abdulin oil and gas region of the Tatarstan Republic." E3S Web of Conferences 411 (2023): 01066. http://dx.doi.org/10.1051/e3sconf/202341101066.
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The paper presents the results of a study of oil-bearing sections of the Vereyian horizon of low-amplitude uplifts in the western marginal part of the Melekess-Abdulin oil and gas region of Tatarstan. It has been established that the main reservoir rocks are algal-peloid packstones, fusulinide grainstones and greywacke fine-grained sandstones. Carbonate reservoirs of the lower part of the section of the Vereyian horizon and sandstones of the upper part of the section are watered to varying degrees, most of them are not promising for development. The productivity of the sections is associated with fusulinide grainstones and underlying algal-peloid packstones that have not experienced intensive waterflooding. As a rule, such lithotypes of carbonate reservoir rocks are in the middle parts of sections of Vereyian age. A feature of the fusulinide limestone layers is their areal inconsistency in thickness, which is due to the facies conditions of the sedimentation basin. Due to this, on some small oil-bearing structures they give good oil inflows, on others they show relatively small debits.
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Bony, Sandrine, and Bjorn Stevens. "Measuring Area-Averaged Vertical Motions with Dropsondes." Journal of the Atmospheric Sciences 76, no. 3 (2019): 767–83. http://dx.doi.org/10.1175/jas-d-18-0141.1.
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Abstract Measurements of vertical profiles of areal-mean mass divergence, vorticity, and vertical velocity, based on dropsondes distributed over an area of 25 000 km2, are presented. The dropsondes were released with high frequency along circular flight patterns during an airborne field campaign taking place over the tropical Atlantic near Barbados. Vertical profiles of the area-averaged mass divergence and vorticity were computed from the horizontal wind profiles, and the area-averaged vertical velocity was then inferred from the divergence. The consistency of measurements over pairs of circles flown within the same air mass demonstrated the reproducibility of the measurements, and showed that they characterize the environmental conditions on the scale of the measurement, rather than being dominated by measurement error or small-scale wind variability. The estimates from dropsondes were found to be consistent with the observed cloud field, with Lagrangian estimates of the mean vertical velocity inferred from the free-tropospheric humidity field, and with the mean vertical velocity derived from simulations using an atmospheric model representing kilometer-scale motions and initialized with meteorological analyses. In trade wind–like conditions, the divergence and vorticity profiles exhibit a rich vertical structure and a significant variability in space and time. Yet a few features appear to be robust, such as the presence of layers of mass convergence at the top of moist layers, extrema of the area-averaged vertical velocity at the top of the subcloud layer and in the midtroposphere, and minima around the trade inversion near 2 km. The analysis of spatial and temporal autocorrelation scales suggests that the divergent mass field measured from dropsondes is representative of the environment of shallow clouds.
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Seol, Myeong-Lok, Inho Nam, Ellie Sadatian, Nabanita Dutta, Jin-Woo Han, and M. Meyyappan. "Printable Gel Polymer Electrolytes for Solid-State Printed Supercapacitors." Materials 14, no. 2 (2021): 316. http://dx.doi.org/10.3390/ma14020316.
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Supercapacitors prepared by printing allow a simple manufacturing process, easy customization, high material efficiency and wide substrate compatibility. While printable active layers have been widely studied, printable electrolytes have not been thoroughly investigated despite their importance. A printable electrolyte should not only have high ionic conductivity, but also proper viscosity, small particle size and chemical stability. Here, gel-polymer electrolytes (GPE) that are compatible with printing were developed and their electrochemical performance was analyzed. Five GPE formulations based on various polymer-conductive substance combinations were investigated. Among them, GPE made of polyvinylidene difluoride (PVDF) polymer matrix and LiClO4 conductive substance exhibited the best electrochemical performance, with a gravimetric capacitance of 176.4 F/g and areal capacitance of 152.7 mF/cm2 at a potential scan rate of 10 mV/s. The in-depth study of the in-plane solid-state supercapacitors based on various printed GPEs suggests that printable electrolytes provide desirable attributes for high-performance printed energy devices such as supercapacitors, batteries, fuel cells and dye-sensitized solar cells.
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Seol, Myeong-Lok, Inho Nam, Ellie Sadatian, Nabanita Dutta, Jin-Woo Han, and M. Meyyappan. "Printable Gel Polymer Electrolytes for Solid-State Printed Supercapacitors." Materials 14, no. 2 (2021): 316. http://dx.doi.org/10.3390/ma14020316.
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Supercapacitors prepared by printing allow a simple manufacturing process, easy customization, high material efficiency and wide substrate compatibility. While printable active layers have been widely studied, printable electrolytes have not been thoroughly investigated despite their importance. A printable electrolyte should not only have high ionic conductivity, but also proper viscosity, small particle size and chemical stability. Here, gel-polymer electrolytes (GPE) that are compatible with printing were developed and their electrochemical performance was analyzed. Five GPE formulations based on various polymer-conductive substance combinations were investigated. Among them, GPE made of polyvinylidene difluoride (PVDF) polymer matrix and LiClO4 conductive substance exhibited the best electrochemical performance, with a gravimetric capacitance of 176.4 F/g and areal capacitance of 152.7 mF/cm2 at a potential scan rate of 10 mV/s. The in-depth study of the in-plane solid-state supercapacitors based on various printed GPEs suggests that printable electrolytes provide desirable attributes for high-performance printed energy devices such as supercapacitors, batteries, fuel cells and dye-sensitized solar cells.
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Ryabogina, N. E., E. D. Yuzhanina, S. N. Ivanov, and A. A. Golyeva. "Microbiomarkers of the local environment and interior of Neolithic and Eneolithic dwellings (settlements of Mergen 6 and 7)." VESTNIK ARHEOLOGII, ANTROPOLOGII I ETNOGRAFII, no. 4(55) (December 23, 2021): 5–16. http://dx.doi.org/10.20874/2071-0437-2021-55-4-1.
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The paper concerns the analysis of the local environment around the multi-layer settlements of Mergen 6 and 7 situated in the immediate vicinity of each other. The settlements existed successively (partly contempora-neously in the early and high Neolithic) in the forest-steppe belt of Western Siberia. Two methods were chosen to obtain the results: spore-and-pollen (palynological) and microbiomorphic analyses of the cultural layers of the settlements of Mergen 6 and Mergen 7. In the settlement of Mergen 6, the following samples were collected for the palynological and microbiomorphic investigation: a vertical column from the center of the ditch of the dwelling no.5; areal soil samples of the dwelling no.5 from underneath the pottery debris of the Neolithic and Eneolithic periods; areal samples from the bottom layer of the dwelling no.21. In the settlement of Mergen 7, two vertical core samples were selected for the pore-and-pollen analysis: in the ditch of the dwelling no.1; and in the inter-dwelling area. Samples from the hearthing of the dwellings and from the inter-dwelling space were collected for the microbiomorphic analysis. The obtained results show that both settlements existed during the forest-steppe conditions, although the original landscapes of the sites chosen by the people for building the settlements were different in the early and high Neolithic. It appears that during the early Neolithic, the settlement of Mergen 6 was associated with an open site with meadow-steppe vegetation; birch forests constituted a small part of the land-scape, whilst there were no pine forests in the close vicinity. During the middle Neolithic, people in the settlement of Mergen 7 preferred to settle in a birch wood, having cleared out a small area to build the dwelling. The results of the microbiomorphic analysis show that, despite the lack of pine forests nearby the settlements, people still used pine tim-ber in housebuilding, apparently, intentionally. The frequent occurrence of remains of the wood detritus at the level of the floor of the dwellings and under pottery supports the initial archaeological observations about timber decking inside the houses. However, pollen and phytolithic studies do not demonstrate a wide use of the wetland waterside vegetation in housebuilding, apparently, because the lake at the time was not overgrown on the banks by reed and cattail. There-fore, despite the close location of the two sites and their similar hunting-fishing specialization of the subsistences, their populations in different chronological periods preferred distinct local conditions.
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Klein, David, Yaolin Xu, Robert Schlögl, and Sébastien Cap. "Low Reversible Capacity of Nitridated Titanium Electrical Terminals." Batteries 5, no. 1 (2019): 17. http://dx.doi.org/10.3390/batteries5010017.
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The currently preferred manufacturing method for Lithium-ion battery (LIB) electrodes is via the slurry route. While such an approach is appealing, the complexity of the electrode layers containing the active materials, conductivity helpers, and binders, has hampered detailed investigations of the active materials. As an alternative, an active material can be deposited as a thin film on a planar substrate, which enables a more robust and detailed analysis. However, due to the small areal capacity of nanometric thin films, the electrochemical activity of the cell casing must be negligible or at least well determined. We reported on the capacity and the differential capacity metrics of several materials used in the construction of the electrical terminals in LIBs. Among these materials, Ti was revealed to have the minimum reversible capacity for lithium-ion storage. The mechanical and electrochemical properties of the Ti–based materials were further improved through surface nitridation with thermal treatment in an ammonia-rich atmosphere. The nitridated Ti electrical terminal achieved a reversible capacity that was at least fifteen times lower than that of stainless steel, with a featureless differential capacity representation creating quasi-ideal experimental conditions for a detailed investigation of electroactive thin films.
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Nael, Manal A., Dmitriy A. Dikin, Natnael Admassu, Omar Bahgat Elfishi, and Simona Percec. "Damage Resistance of Kevlar® Fabric, UHMWPE, PVB Multilayers Subjected to Concentrated Drop-Weight Impact." Polymers 16, no. 12 (2024): 1693. http://dx.doi.org/10.3390/polym16121693.
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The impact resistance of layered polymer structures using polyvinyl butyral (PVB) in combination with Kevlar® fabric and ultra-high molecular weight polyethylene (UHMWPE) were fabricated and tested. Methods of wet impregnation and hot-press impregnation and consolidation of fabric with PVB and UHMWPE were used to manufacture multilayer constructs. All sandwich constructs were fixed to the surface of ballistic clay and subject to a free drop-weight test with a conical impactor having a small contact area. All tests were made at the same impact energy of 9.3 J and velocity of 2.85 m/s. The change in the resistance force was recorded using a piezoelectric force sensor at the time intervals of 40 μs. Using experimental force–time history, the change in the impactor’s velocity, the depth of impactor penetration, the energy transformation at various stages of impactor interaction with the sample, and other parameters were obtained. Three indicators were considered as the main criteria for the effectiveness of a sample’s resistance to impact: (1) minimum deformation, bulging, of the panel backside at the moment of impact, (2) minimum absorption of impact energy per areal density, and (3) minimal or, better yet, no destruction of structural integrity. Under the tested conditions, the rigid Kevlar–PVB–Kevlar sandwich at the frontside and relatively soft but flexible UHMWPE–Kevlar–UHMWPE layers in the middle helped to localize and absorb impact energy, while the backside Kevlar–PVB–Kevlar sandwich minimized local bulging providing the best overall performance. The front layer damage area was very shallow and less than two impactor tip diameters. The backside bulging was also less than in any other tested configurations.
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Kanda, M., M. Kanega, T. Kawai, R. Moriwaki, and H. Sugawara. "Roughness Lengths for Momentum and Heat Derived from Outdoor Urban Scale Models." Journal of Applied Meteorology and Climatology 46, no. 7 (2007): 1067–79. http://dx.doi.org/10.1175/jam2500.1.
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Abstract Urban climate experimental results from the Comprehensive Outdoor Scale Model (COSMO) were used to estimate roughness lengths for momentum and heat. Two different physical scale models were used to investigate the scale dependence of the roughness lengths; the large scale model included an aligned array of 1.5-m concrete cubes, and the small scale model had a geometrically similar array of 0.15-m concrete cubes. Only turbulent data from the unstable boundary layers were considered. The roughness length for momentum relative to the obstacle height was dependent on wind direction, but the scale dependence was not evident. Estimated values agreed well with a conventional morphometric relationship. The logarithm of the roughness length for heat relative to the obstacle height depended on the scale but was insensitive to wind direction. COSMO data were used successfully to regress a theoretical relationship between κB−1, the logarithmic ratio of roughness length for momentum to heat, and Re*, the roughness Reynolds number. Values of κB−1 associated with Re* for three different urban sites from previous field experiments were intercompared. A surprising finding was that, even though surface geometry differed from site to site, the regressed function agreed with data from the three urban sites as well as with the COSMO data. Field data showed that κB−1 values decreased as the areal fraction of vegetation increased. The observed dependency of the bulk transfer coefficient on atmospheric stability in the COSMO data could be reproduced using the regressed function of Re* and κB−1, together with a Monin–Obukhov similarity framework.
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Seenirajan, M., M. Natarajan, R. Thangaraj, and Vivek S. Kumar. "Importance of Morphometry Studies, Landform Processes Using Remote Sensing and GIS for Tamiraparani Subbasin, Tirunelveli District, Tamil Nadu, India." Journal of Computational and Theoretical Nanoscience 16, no. 2 (2019): 639–48. http://dx.doi.org/10.1166/jctn.2019.7783.
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An endeavor is created to think about the importance of morphometry, incorporating RS information and strategies notwithstanding the ordinary techniques in a GIS stage. A morphometric evaluation of Tamiraparanisubbasin was completed to decide the seepage attributes utilizing GIS system. The examination has exhibited the potential utilization of the remotely detected information and the GIS in assessment of linear, relief and areal morphometric metrics. By breaking down their impact on the origin and procedures of landforms and qualities of soil metrics like surface, waste and land erosion circumstances. The visual translation of satellite information is utilized for dissecting the topographical, landforms and land erosion attributes in conjunction with seepage design encourages powerful depiction of particular features to assess the impact of drainage morphometry. After the execution, the model gives a seepage bowl Strahler's network stream organize upheld by topical layers like perspective, incline, help, and seepage mass. The proposed design uncovers the waste region of this hub is 734.84 km2 and presents subdendritic to dendritic seepage design. The bowl incorporates seventh request stream and for the most part commanded by bring down stream pattern. The bowl incorporates seventh request stream and generally commanded by bring down stream arrange. The slant of the investigation region shifts from 0 in the east to 61 tin the direction opposite to East. The nearness of WG is the head regulatory element for the slant variety. Besides, the slant variety is controlled by the nearby lithology and erosion cycles. The bifurcation proportion shows that the topographical assembly has small effect on the waste systems and the seepage mass uncovers the idea of subsurface strata is porous.
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Nowak, L. G., M. H. J. Munk, P. Girard, and J. Bullier. "Visual latencies in areas V1 and V2 of the macaque monkey." Visual Neuroscience 12, no. 2 (1995): 371–84. http://dx.doi.org/10.1017/s095252380000804x.
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AbstractLatencies to small flashing spots of light were measured in different layers of areas V1 and V2 in anesthetized and paralyzed macaque monkeys. The shortest latencies were found in layers 4Cα and 4B of area V1. Latencies in layer 4Cβ were on average 20 ms longer than those in 4Cα and 4B. The shortest latencies in area V2 were observed in the infragranular layers and they did not differ significantly from those found in the infragranular layers in V1. Similarly, latencies in the supragranular layers of V2 were not significantly different from those measured in the supragranular layers of V1. These results show that, in area V1, neurons of the magnocellular pathway are activated on average 20 ms earlier than those of the parvocellular pathway. Our data also suggest that much processing begins simultaneously in areas V1 and V2.
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Grammatikopoulos, T. A., A. H. Clark, T. H. Pearce, and D. A. Archibald. "Genesis of the Olden wollastonite skarn, Sharbot Lake domain, Central Metasedimentary Belt, Grenville Province, southeastern Ontario, Canada." Canadian Journal of Earth Sciences 42, no. 8 (2005): 1401–17. http://dx.doi.org/10.1139/e05-040.
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With a resource of ∼2.8 Mt at 30%35% wollastonite occurring at a depth of about 75 m, the Olden (formerly Hawley) prospect is the largest of a swarm of skarns hosted by amphibolite facies, dominantly calcitic marble that occurs adjacent to and as inliers within the Mountain Grove pluton. The post-kinematic intrusion comprises units with a wide compositional range from anorthositic gabbro to alkali-feldspar granite and syenite and widely exhibits megascopic fabrics recording magma comingling and mixing. Isotope dilution thermal ionization mass spectrometry (IDTIMS) dating of zircon separates from a hornblende diorite unit yields a 207Pb206Pb age of 1153 ± 2 Ma, significantly older than the contiguous 1070 ± 3 Ma McLean granite. Al-in-hornblende geobarometry on several Mountain Grove units indicates that the intrusion crystallized at pressures of 250470 MPa, equivalent to mesozonal depths of 1015 km. The main exoskarn body, ∼200 m long and up to 50 m wide, is dominated by wollastonite, clinopyroxene (Di7394Hd219), and calcic garnet (Gr5283And1237) and ranges from massive to podiform. The eastern termination exhibits rhythmically alternating wollastonite- and calcite-rich layers, 10 cm wide and locally with chevron-shaped crenulations. These layers bear no relationship to bedding or metamorphic foliation and are interpreted as “wrigglitic,” i.e., they are a record of a metasomatic front that migrated. Veins of garnetpyroxenevesuvianite cut the main exoskarn. Retrograde phlogopite-rich skarns, with erratic serpentine and brucite, contain variable sphalerite and pyrite. Restricted pyroxenegarnet (wollastonitescapolite) endoskarn is developed in intrusive rocks contiguous with the exoskarn. Skarn development is ascribed to H2O-rich (XCO2 < 0.3) magmatogene brines and high temperatures (T = 500650 °C), which caused intense Si, Al, and Fe metasomatism of the marbles, hydrothermal activity taking place at considerable depth. The occurrence of wollastonite around the periphery of the small Long Lake sphalerite deposit, restricted to a marble roof pendant in the Mountain Grove pluton 2.1 km east-northeast of the Olden prospect, indicates that this base-metal mineralization may be an exoskarn, rather than metamorphosed Mississippi Valley type. Incremental-heating 40Ar39Ar dating of hornblende and biotite from the Mountain Grove diorite yields plateau ages of 1058 ± 14 and 1047 ± 4 Ma, respectively, and an exoskarn phlogopite age of 1074 ± 5 Ma. A genetic relationship between hydrothermal activity and the McLean pluton cannot be ruled out, but a parental role for the older Mountain Grove pluton is favoured on the basis of the close areal relationships of skarn bodies and that intrusion.
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Jerauld, G. R. "A Case Study in Scaleup for Multicontact Miscible Hydrocarbon Gas Injection." SPE Reservoir Evaluation & Engineering 1, no. 06 (1998): 575–82. http://dx.doi.org/10.2118/53006-pa.
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Summary We describe the strategy and results of scaleup done to simulate a multicontact miscible hydrocarbon water alternating gas (WAG) injection process. To adequately model both oil recovery and solvent retention in WAG, one must model three-phase flow including gas trapping. Scaleup of the multicontact miscible gas process is particularly difficult because of the very fine-scale structure of the gas fingers and the miscible front. The case studied is a heterogeneous mixed wet reservoir with a transition zone down to an underlying aquifer. The objective was to develop pseudo relative permeability curves and other parameters that are suitable for running in a full-field limited compositional model with three hydrocarbon components. Both history-matching and systematic approaches were used to generate pseudo relative permeability curves that reproduced results of high-resolution, fully compositional (FC) reference simulations. Dynamic pseudoization techniques were used to derive first guesses at pseudos, but required further calibration to reproduce reference simulations successfully. In matching incremental miscible gas/oil recovery timing and solvent retention, varying three phase water relative permeability was much more effective than varying the mixing parameter. The predictive capability of pseudos was tested for changes with respect to slug size, WAG ratio, and solvent enrichment. Pseudos derived for one pattern or cross section were tested in other patterns or cross sections. Pseudos worked well with respect to changes in WAG ratio, fairly well with respect to changes in solvent enrichment, and moderately well for changes in slug size. They were less robust with respect to changes in description. Introduction Estimation of the incremental recovery and solvent utilization in a multicontact miscible hydrocarbon gas process is challenging. On one hand, important features of the process occur over small-length scales and cannot be estimated readily without very fine-grid, FC simulation. The condensing/vaporizing drive entails the concentration of enriching components into a narrow miscible front that is smeared by coarse areal gridding. High vertical grid refinement is needed to capture thin gas fingers that form within layers of high permeability. SPE 53006 was revised for publication from paper SPE 39626, first presented at the 1998 SPE/DOE Improved Oil Recovery Symposium, Tulsa, Oklahoma, 19-22 April.
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Vlasov, I. V., A. I. Gordienko, and V. M. Semenchuk. "Effect of thermal cycles on formation of pearlitic heat-resistant steel structure under wire arc additive manufacturing." Izvestiya. Ferrous Metallurgy 68, no. 1 (2025): 51–59. https://doi.org/10.17073/0368-0797-2025-1-51-59.
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The authors investigated the microstructure and mechanical properties of a model wall manufactured by arc wire 3D printing. 3D printing was performed using heat-resistant pearlitic steel wire in coldArc reduced heat input mode. Stationary thermal imager was employed to analyze the thermal cycles during layer deposition. Compressed air cooling to 200 °C was applied before each layer deposition to reduce heat accumulation. The high temperature gradients between the molten metal and the cooled layer resulted in areas with non-uniform structure, typical of welded joints after arc welding. Such areas with non-uniform structure were formed during the printing of each new layer and repeated throughout the wall height. It was observed that each solidified layer undergoes cyclic thermal effects during the deposition of subsequent ten layers. Intensive heating from deposition of two to three new layers leads to partial structural-phase transformations in the underlying layer. Deposition of the next 7 – 8 layers leads to heating similar to the “tempering” thermal operation. Microstructure analysis across different areas of the wall revealed acicular bainite with a small proportion of lath ferrite, bainitic ferrite, and martensitic-austenitic constituents. A slight increase in the width dimensions of acicular structure laths was observed with increasing wall height compared to the lower layers. The highest microhardness values were observed at the wall and substrate fusion zone (320 ± 7 kgf/mm2) due to rapid heat conduction and high cooling rates during the initial stages of printing. In the wall bulk, microhardness values ranged from 260 to 300 kgf/mm2. The scatter of values and the periodic nature of the microhardness curve are associated with the formation of areas with non-uniform structure within each deposited layer of the wall. The wall material exhibits high strength characteristics (up to 800 MPa) and relative elongation (9 – 12 %).
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Ryazantsev, Anatoly, Alexander Zazulya, Lyubov Kozlova, Evgeny Evseev, and Olga Anufrieva. "HOSE SPRINKLERS FOR WATERING SMALL AREAS." SCIENCE IN THE CENTRAL RUSSIA, no. 6 (December 27, 2024): 64–74. https://doi.org/10.35887/2305-2538-2024-6-64-74.
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The issues of evaluation of technological parameters of hose sprinklers (HS) operating in positions or in motion are considered. The following technological parameters: precipitation layer per pass, average rain intensity, effective irrigation coefficient and average diameter of raindrops were calculated in the course of theoretical studies. Experimental studies on determination of rain quality were conducted in Moscow region during irrigation of cabbage in cassettes and radish. Rain distribution was studied on two variants of HS working bodies in laboratory and production conditions. Irrigation radius by measuring with a tape the flight range of drops from HS nozzles and rain quality parameters were determined. Precipitation layer per pass was determined using 0.5 l rain gauges during operation of the sprinkler in motion at a pressure of 0.3 MPa. Studies of HS samples showed that when equipped for operation in motion, they provide water consumption of 0.56…0.60 l/s at a pressure of 0.2 MPa and 0.83…0.90 l/s at a pressure of 0.3 MPa; the movement of the SD samples should be carried out at a speed of 0.08 ... 1.0 m / min; the highest quality irrigation is achieved when arranging the SD with overlapping according to the scheme of 10x10 m; the rain layer per pass depends on the water pressure; the coefficient of effective irrigation at a pressure of 0.2 MPa and when arranging every 21 m was 0.74. Technical and economic calculations confirm the high economic efficiency of the created technical means, ensuring a reduction in capital costs by 60%. The DM-1 SD has passed state tests and is recommended for serial production. Hose sprinklers of the DS-0.6 and DS-1 type and their modifications for irrigation of small areas (up to 1 ha) on the basis of the conducted research and tests will find wide application in sprinkling irrigation of various agricultural crops in farms, gardening, household and individual farms.
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Tate, Andrew K., and Joseph G. Malpeli. "Effects of Focal Inactivation of Dorsal or Ventral Layers of the Lateral Geniculate Nucleus on Cats' Ability to See and Fixate Small Targets." Journal of Neurophysiology 80, no. 4 (1998): 2206–9. http://dx.doi.org/10.1152/jn.1998.80.4.2206.
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Tate, Andrew K. and Joseph G. Malpeli. Effects of focal inactivation of dorsal or ventral layers of the lateral geniculate nucleus on cats' ability to see and fixate small targets. J. Neurophysiol. 80: 2206–2209, 1998. To reveal contributions of different subdivisions of the lateral geniculate nucleus (LGN) to visuomotor behavior, segments of either layer A or the C layers were inactivated with microinjections of γ-aminobutyric acid while cats made saccades to retinally stabilized spots of light placed either in affected regions of visual space or mirror-symmetric locations in the opposite hemifield. Inactivating layer A reduced the success rate for saccades to targets presented in affected locations from 82.4 to 26.8% while having no effect on saccades to the control hemifield. Saccades to affected sites had reduced accuracy and longer initiation latency and tended to be hypometric. In contrast, inactivating C layers did not affect performance. Data from all conditions fell along the same saccade velocity/amplitude function (“main sequence”), suggesting that LGN inactivations cause localization deficits, but do not interfere with saccade dynamics. Cerebral cortex is the only target of the A layers, so behavioral decrements caused by inactivating layer A must be related to changes in cortical activity. Inactivating layer A substantially reduces the activity of large subsets of corticotectal cells in areas 17 and 18, whereas few corticotectal cells depend on C layers for visually driven activity. The parallels between these behavioral and electrophysiological data along with the central role of the superior colliculus in saccadic eye movements suggests that the corticotectal pathway is involved in both deficits and remaining capacities resulting from blockade of layer A.
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Jain, Neeraj, Todd M. Preuss, and Jon H. Kaas. "Subdivisions of the visual system labeled with the Cat-301 antibody in tree shrews." Visual Neuroscience 11, no. 4 (1994): 731–41. http://dx.doi.org/10.1017/s0952523800003035.
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AbstractThe monoclonal antibody Cat-301 was used to stain neurons and neuropil in the visual thalamus and cortex of tree shrews —small, highly visual mammals that are closely related to primates. Previously, this antibody has been found to label neurons associated with the Y-cell stream of processing in cats and the magnocellular or M-cell stream in macaque monkeys. In tree shrews, the antibody selectively labeled layers 1, 2, 4, and 5 of the dorsal lateral geniculate nucleus, layers that are likely to contain neurons previously classified as Y-cells. Of the two layers that contain W-cells, layer 3 was unlabeled and layer 6 was lightly labeled. In area 17, layer 3c was densely stained, as in cats and macaque monkeys. The external half of layer 5 was also densely stained, in contrast to cats where the internal half of layer 5 is stained and macaques where layer 5 is sparsely stained. Area 18 was characterized by dense, uniform staining of inner layer 3 and outer layer 5, but no pattern of alternating light and dense bands crossed the width of area 18 as in macaques. Dense labeling of these same sublayers occurred in cortical areas TA and TD just lateral to area 18. Area TD may be the homologue of area MT of primates, which also stains densely with Cat-301 in macaques. These results indicate that Cat-301 differentially labels layers and areas in the visual system of tree shrews, and raise intriguing issues of comparison among tree shrews, primates, and cats.
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Iwahara, Y., H. Shirakawa, K. Miyashita, and Y. Mitani. "Spatial niche partitioning among three small cetaceans in the eastern coastal area of Hokkaido, Japan." Marine Ecology Progress Series 637 (March 5, 2020): 209–23. http://dx.doi.org/10.3354/meps13232.
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Spatial niche partitioning of marine mammals is thought to be caused by dietary differences. However, due to the difficulty involved with conducting simultaneous marine predator and prey distribution surveys at the same scale, marine mammals have not been studied alongside their prey distribution. To understand the spatial niche overlap between 3 small cetaceans observed in the eastern coastal waters of Hokkaido, Japan (Pacific white-sided dolphin Lagenorhynchus obliquidens, Dall’s porpoise Phocoenoides dalli, and harbor porpoise Phocoena phocoena), and the mechanisms behind the differences in their distributions, visual and hydroacoustic surveys using a quantitative echosounder were concurrently conducted. A clear spatial niche overlap was observed between the Pacific white-sided dolphin and Dall’s porpoise, whereas the spatial overlap was moderate between the harbor porpoise and the other 2 species. In areas where Pacific white-sided dolphins were observed, potential prey was abundant in a shallower layer, at approximately 80-90 m depth. On the other hand, potential prey was more abundant in deeper layers in areas where Dall’s and harbor porpoises were observed. Water depth affected the potential prey abundance at all depth layers (0-300 m), as potential prey were more abundant in areas with a shallower water depth. Additionally, potential prey were more abundant in shallower layers (3-200 m) than in deeper layers (200-300 m), where the maximum water depth was 3000 m. The differences in spatial niche among Pacific white-sided dolphin, Dall’s porpoise, and harbor porpoise might cause their dietary differences, as they are epipelagic feeders, midwater feeders, and both epipelagic and midwater feeders, respectively.
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Kuhn, N. J., and H. Zhu. "GIS-based modeling of runoff source areas and pathways." Geographica Helvetica 63, no. 1 (2008): 48–57. http://dx.doi.org/10.5194/gh-63-48-2008.
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Abstract. The application of runoff models that rely on calibration to future land use and climate conditions is restricted to situations where the reaction of Hydrologic Response Units to environmental change is known. This limitation and the ensuing uncertainty of model results can be avoided when a risk-based approach to landscape and runoff analysis is taken. GIS-based landscape analysis provides the possibility of assessing the risks associated with non-linear responses of Hydrologic Response Units to changing rainfall and land use. In this paper, a runoff module designed for IDRISI-Andes to calculate runoff amount and routing for single or multiple rainfall events on a hillslope at small catchment scale is presented. The module is raster-based and uses layers with topographic and hydrological parameters to calculate a spatially distributed output layer of surface runoff. Conceptually, the module extrapolates point data of infiltration capacity onto a field or hillslope. A spatially distributed runoff map is calculated based on the addition of layers with rainfall data and the routing of runoff through pathways connecting pixels in a digital elevation model. Unlike outlet-based runoff modeling, the need for parameterization of the catchment is kept to a minimum. The application of the RUNOFF module in a test area in the Eifel region of Germany indicated that runoff from grassland is sensitive to small increases in rainfall intensity and soil compaction. The spatial patterns of infiltration capacity also contribute significantly to the non-linearity of the test area reaction to changing rainfall and soil hydrologic properties.
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Burnett, Richard D., and Jack C. Hall. "Significance of ultrastructural features in etched conodonts." Journal of Paleontology 66, no. 2 (1992): 266–76. http://dx.doi.org/10.1017/s0022336000033783.
Full textAbstract:
Acid etching combined with scanning electron microscopy (S.E.M.) accentuates a variety of conodont microstructural patterns as compared to unetched specimens. External and internal organic layers surrounding apatitic lamellae are found with internal organic layers apparently thinner than their external counterparts. This may imply partial removal of the outermost organic layer prior to secretion of the next lamella. Etching also provides evidence of internally preserved striate ornament. Polygonal etch artifacts and zones of crystallites aligned in small areas are interpreted as possible sites for apatite biomineralization.
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Li, Xue, Jin Duo Ye, Chun Qui Zhang, Qian Qian Tian, Xian Kang Wang, and Li Min Dong. "Numerical Simulation about Stretching Process in Different Layers of Cartilage." Applied Mechanics and Materials 441 (December 2013): 480–83. http://dx.doi.org/10.4028/www.scientific.net/amm.441.480.
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Cartilage with complex structure is a porous viscoelastic material. The direction of arrangement of collagen fibers in different layer regions directly affects the mechanical properties of the cartilage layer region. It is very important to use the method of numerical simulation for studying cartilage damage and repair through experimental measurements of cartilage mechanical parameters of the different layers. Because of the relatively small size of the cartilage, it is very difficult to measure mechanical parameters of cartilages by tensile test. The paper for main problems in the tensile test of cartilages, first by porcine articular cartilage compression testing, measuring the displacement of cartilage areas of different layers, according to the characteristics of the displacement determines the size of areas of different layers of cartilage, and then designed the cartilage and substrate stretching models. Model includes two forms of direct bonding and embedding bonding to simulate stretching process of different layers of the cartilage area in numerical way, displacement fields and stress-strain fields of stretching cartilage in different layer regions are derived. The numerical results show that using the way of embedded bonding can make stress of articular well-distributed without stress concentration, so it is a good way of bonding methods. Paper of the research work laid the foundation for measuring mechanical parameters of cartilage by stretch experiment.
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Behrens, R. A., M. K. MacLeod, T. T. Tran, and A. C. Alimi. "Incorporating Seismic Attribute Maps in 3D Reservoir Models." SPE Reservoir Evaluation & Engineering 1, no. 02 (1998): 122–26. http://dx.doi.org/10.2118/36499-pa.
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Summary We introduce a new geostatistical method to incorporate seismic attribute maps into a three-dimensional (3D) reservoir model. The method explicitly honors the difference in vertical resolution between seismic and well-log data. The method, called sequential Gaussian simulation with block Kriging (SGSBK), treats the seismic map as a soft estimate of the average reservoir property. With this method, the average of the cell values in anyone vertical column of grid cells is constrained by the value of the seismic map over that column. The result is a model that contains vertical variability driven by well logs and the vertical-variogram model and spatial variability driven by the seismic map and the areal-variogram model. Introduction Reservoir models for flow simulation and volumetrics are often built from well logs by use of geostatistical methods. The well logs provide good vertical resolution required for accurate flow simulation, but they represent only a small portion of the reservoir. Seismic data is very complementary because it is areally dense, but vertically sparse relative to well-log data. The goal of the method presented is to integrate seismic data that more closely represents interval-average rock properties, and well-log data that more closely represents point-rock properties. This "volume support" difference is acknowledged and treated in the SGSBK method presented in this paper. Geostatistical methods that aim to build 3D reservoir models must honor the difference in volume support between well and seismic data, whereas methods for areal two-dimensional (2D) models do not. Averaged or integrated log properties no longer represent point properties but rather interval properties with lower vertical resolution similar to seismic data. The differences in volume support between the log average and seismic data are acceptable, because both represent large volumes of rock. No special treatment for volume support is thus used in areal 2D simulations that use both log and seismic-map data. This special circumstance is not true for 3D models, so any 3D method to incorporate log data and seismic data should address the volume-support problem. Literature Review There are several problems associated with integrating seismic and well data for 3D reservoir characterization: the seismic data must be converted from time to depth domain; seismic data is band-limited, whereas well data has both high- and low-frequency components; seismic data must be calibrated to well data; and a well measurement is of quasipoint support, whereas a seismic datum informs a much larger volume of reservoir rock. (The term quasipoint properties is used to represent the properties in a single cell rather than a core plug or smaller.) Several authors have worked on the calibration issue. Fournier1 and Fournier and Derain2 performed multivariate statistical analysis on a calibration dataset consisting of well logs and nearby seismic traces to establish a nonparametric regression between petrophysical properties and some seismic attributes. This regression is then applied on the seismic data to obtain seismic-derived reservoir properties that are, in turn, incorporated with well information using cokriging (and variants thereof). In their studies, Fournier and Fournier and Derain considered average properties (e.g., average porosity,1 cumulative lithofacies thickness2), because it was not possible to assess vertical distributions of reservoir properties from their limited-time-resolution seismic traces. Zhu and Journel3 proposed a different use of the well-seismic calibration dataset. In lieu of a regression, the well (hard) and seismic (soft) data are encoded as local prior probability distributions which are then "updated" into posterior distributions during the sequential indicator simulation process.4 Values of the property of interest are drawn randomly from these local posterio~ distributions. This method was found to be superior by Araktingi et al.,5 who applied it to a synthetic seismic dataset. Similarly, Doyen and Psaila6 used a "seismic likelihood function" constructed from a seismic-lithotype crossplot to modify the local probability distributions generated by the sequential indicator simulation algorithm; the result is lithologic models that are constrained by seismic data. Xu et al.7 proposed the sequential Gaussian simulation (SGS) with collocated cokriging algorithm as a more efficient, albeit less rigorous, alternative to SGS with full cokriging.8,9 This algorithm requires the correlation coefficient between the well and seismic data, and their cross-covariance model is derived from the covariance model of the well data. Xu et al. showed a 2D study where the algorithm was applied to incorporate well data and seismic two-way travel times to create realizations of the structure top of a salt dome. Yang et al.10 used SGS with collocated cokriging to construct 3D porosity models conditional to both well and seismic data. In one approach, the seismic amplitude was used as soft data; the required correlation coefficient was obtained by crossplotting averaged porosity and absolute seismic amplitude. In another approach, the inverted seismic impedance was used as soft data. Although not explicitly stated by the authors, either an interpolation or simulation procedure was used to populate the simulation grid with soft seismic data, because the vertical resolution of the seismic data is much less than that of the simulation grid. Gorell1 proposed a method to account for the difference in vertical resolution of seismic and well data. First, the wells are subdivided vertically into correlatable layers. Each layer is then populated with porosity values using 2D geostatistical operations. Finally, linear rescaling is performed on each vertical column of the simulation grid to ensure that a seismic-derived average porosity map is honored. The resulting 3D porosity model honors both the vertical variations at the well locations and average porosity map. This technique can be applied to several different vertical zones of the reservoir with different average porosity maps, and the rescaled results are stacked together at the end. As pointed out by the author, this technique requires that the wells be vertical or the well data may not be honored. In addition, vertical correlation of porosity between layers is only honored indirectly through the interwell-correlation process and the probability density function (pdf) of the point data is distorted, as will be shown later. Burns et al.12 used a similar resealing procedure to improve the description of a 100-ft-thick reservoir.
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Volkov, Anatoly F. "Spatial-temporal patterns of euphausiids ecology in the Okhotsk Sea." Izvestiya TINRO 180, no. 1 (2015): 128–39. http://dx.doi.org/10.26428/1606-9919-2015-180-128-139.
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The most common regularities in spatial distribution of mass Euphausia species and their size classes and ontogenetic stages are determined for the Okhotsk Sea using the data averaging by biostatistical areas and applying the average results to the centers of the areas that allows to smooth small-scale patterns as patchiness. Thysanoessa raschii and Th. inermis occupy mostly shelf areas and Th. longipes and Euphausia pacifica - deep-water areas; among them Th. raschii and Th. longipes are more abundant and Th. inermis and E. pacifica are supposedly allochtonous species which penetrate to the Okhotsk Sea through the Kuril Straits, so they are distributed mainly in the southern part of the Sea. Mean biomass and abundance of all species in the upper (0-50 m) and deeper (50-200 m) layers are calculated for each stage and size class in the daytime and nighttime, separately: most of them, including both adults and furcilias, concentrate mainly in the deeper layer and their night biomass is higher in both layers though about a half of animals raise to the sea surface at night. Only eggs, nauplii and calyptopes of euphausiids don’t change their abundance considerably between day and night, and most of them occupy the upper layer round the clock. Obviously, the increasing of late furcilias and adults in the deeper layer at night is caused by their diurnal migration from the layers below 200 m. Seasons of the highest abundance for early stages come in natural order that is a sign of their short duration.
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Tsau, Yang, Li Guan, and Jian-Young Wu. "Epileptiform Activity Can Be Initiated in Various Neocortical Layers: An Optical Imaging Study." Journal of Neurophysiology 82, no. 4 (1999): 1965–73. http://dx.doi.org/10.1152/jn.1999.82.4.1965.
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The initiation site for triggering epileptiform activity was investigated via optical imaging using voltage-sensitive dyes in the neocortical slice perfused with artificial cerebral spinal fluid containing nominally zero magnesium. The neocortical slices (400-μm thick) were harvested from Sprague-Dawley rats (P21–28). Optical imaging was made by using a high speed photodiode array. Spontaneous epileptiform activity emerged 20–40 min after the preparation was perfused with zero-magnesium solution. There was a good correspondence between electrical and optical signals ( n = 46), although the details of the two recordings were somewhat different. The initiation sites were measured optically in 11 preparations. Among them, four were found to be located in superficial layers, two were found in middle layers, and five were found in deep layers. Repeated recordings revealed that these initiation sites were relatively stable; shifting of the initiation site was not observed. Therefore spontaneous epileptiform activity could be initiated in various cortical layers, from layer I to layer VI. The activation started from a small area <0.04 mm3 and spread smoothly from the initiation site to adjacent cortical areas, suggesting that the initiation site is very confined to one of the cortical layers. The initiation sites were distributed randomly in various cortical areas, and no higher probability was found in a special cortical region. Electrical stimulation delivered via a glass microelectrode filled with 2 M NaCl (2–5 MΩ) could reliably trigger epileptiform activity that had the same characteristics as the spontaneous activity. The cortical neurons activated directly by the stimulation were around the electrode’s tip and estimated to be within a 50-μm area, suggesting that only a few neurons were needed to form an initiation site. Because the timing for stimulation was arbitrary and the evoked events were initiated independent of discharges of neurons in any other layers, it is likely that the initiation site for epileptiform activity in various cortical layers is independent of the control of layer V pyramidal neurons. Together these finding suggest that the epileptiform focus is confined and can be formed in several (probably all) neocortical layers and in many cortical areas. The initiating neurons may be of different types because neuronal types in various cortical layers are different.
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Liu, Hansen, Kuangang Fan, Qinghua Ouyang, and Na Li. "Real-Time Small Drones Detection Based on Pruned YOLOv4." Sensors 21, no. 10 (2021): 3374. http://dx.doi.org/10.3390/s21103374.
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To address the threat of drones intruding into high-security areas, the real-time detection of drones is urgently required to protect these areas. There are two main difficulties in real-time detection of drones. One of them is that the drones move quickly, which leads to requiring faster detectors. Another problem is that small drones are difficult to detect. In this paper, firstly, we achieve high detection accuracy by evaluating three state-of-the-art object detection methods: RetinaNet, FCOS, YOLOv3 and YOLOv4. Then, to address the first problem, we prune the convolutional channel and shortcut layer of YOLOv4 to develop thinner and shallower models. Furthermore, to improve the accuracy of small drone detection, we implement a special augmentation for small object detection by copying and pasting small drones. Experimental results verify that compared to YOLOv4, our pruned-YOLOv4 model, with 0.8 channel prune rate and 24 layers prune, achieves 90.5% mAP and its processing speed is increased by 60.4%. Additionally, after small object augmentation, the precision and recall of the pruned-YOLOv4 almost increases by 22.8% and 12.7%, respectively. Experiment results verify that our pruned-YOLOv4 is an effective and accurate approach for drone detection.
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Van Den Broeke, Matthew. "Effects of Mid- and Upper-level Drying on Microphysics of Simulated Supercell Storms." E-Journal of Severe Storms Meteorology 9, no. 3 (2021): 1–29. http://dx.doi.org/10.55599/ejssm.v9i3.55.
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Conceptual differences are presented among supercell storms simulated with midlevel and deep dry layers of varying magnitude. Initial patterns are identified which should be studied more comprehensively using observed or simulated data. These initial results indicate that mixing ratios of small ice particles are most sensitive to the depth of a dry layer rather than to its magnitude, with fewer particles in simulations containing a deep dry layer. Hail from frozen drops may be most abundant when a deep layer is dried, and bursts of hail species reaching low levels may be followed 15-20 min later by an increase in low-level vertical vorticity associated with the mesocyclone. Warm rain occurs repeatedly on the upshear side of the echo appendage, is especially variable in quantity, and is disfavored in simulations with a dry layer at midlevels. Increases in warm rain mixing ratio may be followed 10-20 min later by an increase in low-level vertical vorticity, though this association is sensitive to location of the warm rain and concurrent microphysical and dynamical processes. In simulations with substantial dry layers, vertical vorticity was concentrated more rapidly in association with the mesocyclone at low levels. Storms in simulations with deep dry layers produced larger areas of updraft >10 m s-1 at 1000 m AGL, and produced strong updraft more quickly than moister soundings. These results may be applicable when storms move into areas with different moisture characteristics from where they form, and should be supplemented by additional microphysical observations.
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Zhang, Ying, Shuanghao Zheng, Feng Zhou, et al. "Multi‐Layer Printable Lithium Ion Micro‐Batteries with Remarkable Areal Energy Density and Flexibility for Wearable Smart Electronics." Small 18, no. 5 (2021): 2104506. http://dx.doi.org/10.1002/smll.202104506.
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Williams, Gareth, and Andrew Chadwick. "Quantitative seismic analysis of a thin layer of CO2 in the Sleipner injection plume." GEOPHYSICS 77, no. 6 (2012): R245—R256. http://dx.doi.org/10.1190/geo2011-0449.1.
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Time-lapse seismic reflection data have proved to be the key monitoring tool at the Sleipner [Formula: see text] injection project. Thin layers of [Formula: see text] in the Sleipner injection plume show striking reflectivity on the time-lapse data, but the derivation of accurate layer properties, such as thickness and velocity, remains very challenging. This is because the rock physics properties are not well-constrained nor are [Formula: see text] distributions on a small scale. However, because the reflectivity is dominantly composed of interference wavelets from thin-layer tuning, the amplitude and frequency content of the wavelets can be diagnostic of their temporal thickness. A spectral decomposition algorithm based on the smoothed pseudo Wigner-Ville distribution has been developed. This enables single frequency slices to be extracted with sufficient frequency and temporal resolution to provide diagnostic spectral information on individual [Formula: see text] layers. The topmost layer of [Formula: see text] in the plume is particularly suitable for this type of analysis because it is not affected by attenuation from overlying [Formula: see text] layers and because there are areas in which it is temporally isolated from deeper layers. Initial application of the algorithm to the topmost layer shows strong evidence of thin-layer tuning effects. Analysis of tuning frequencies on high-resolution 2D data suggests that layer two-way temporal thicknesses in the range 6 to 11 ms can be derived with an accuracy of c. 2 ms. Direct measurements of reflectivity from the top and the base of the layer permit calculation of layer velocity, with values of around [Formula: see text], in reasonable agreement with existing rock physics estimates. The frequency analysis can, therefore, provide diagnostic information on layer thicknesses in the range of 4 to 8 ms. The method is currently being extended to the full 3D time-lapse data sets at Sleipner.
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Zaumseil, P., G. Weidner, and T. Schroeder. "X-Ray Characterization of the Lattice Perfection of Heteroepitaxial SIS Structures." Solid State Phenomena 131-133 (October 2007): 619–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.131-133.619.
Full textAbstract:
The crystallographic structure of semiconductor - insulator - semiconductor (SIS) structures consisting of a Si(111) substrate, Pr2O3 and Y2O3 insulating high-k materials, and Si cap layer was characterized by a combination of X-ray pole figure measurement and conventional X-ray diffraction. Oxide and Si cap layer were grown by molecular beam epitaxy and have the same 111 lattice orientation as the substrate. It is shown that the oxide layers grow in a type B stacking orientation only, while the epi-layer exhibits exclusively the same type A orientation as the substrate. A small fraction of the epi-Si lattice was identified with 511 netplanes parallel to the surface. TEM investigations identify these areas as structural defects between Si grains of differing stacking sequence.
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Karimah, Karimah, Adi Susilo, Eko Andi Suryo, Aunur Rofiq, and Hasan Muhammad F.R. "Analysis of Potential Landslide Areas Using Geoelectric Methods of Resistivity in The Kastoba Lake, Bawean Island, Indonesia." Jurnal Penelitian Pendidikan IPA 8, no. 2 (2022): 660–65. http://dx.doi.org/10.29303/jppipa.v8i2.1414.
Full textAbstract:
Kastoba Lake in Bawean Island Indonesia is a tourist attraction that has a level of vulnerability in landslide disasters. The landslides has been happen. From the large and small scale in the Kastoba Lake. Base on the problem, the landslides occured due to the field of derailment. According to the above statement, it was necessary to know the subsurface structure and the field of avalanche derailment in the kastoba lake area. This data was allowed by geophysical resistivity method which a dipole-dipole configuration with 4 measurement points. The acquisition of data was based on preliminary studies from the analysis of landslide vulnerability level maps (DEM Alos data processing) that have been done first. The results of lithological analysis with geoelectric resistivity methods in this research obtained three layers of subsurface structure, namely top soil (top layer) with a resistivity value of 7-110 Ωm, clay (middle layer) which was a resistivity value of 110-210 Ωm and lava (bottommost layer) which was a resistivity value of 210-357 Ωm. The field of gelincir in the research area was on the top layer of soil composed of weathering of rocks mixed with organic material or leaf/tree decay with an average depth of 7.25 meters. Thus, this research can be one of the parameters of landslide disaster mitigation in the development of geotourism in Kastoba Lake
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Freund, Niklas, Martin David, David Böhler, et al. "Shotcrete 3D Printing ‐ Interaction of nozzle geometry, homogeneity and hardened concrete properties." ce/papers 6, no. 6 (2023): 746–54. http://dx.doi.org/10.1002/cepa.2818.
Full textAbstract:
AbstractShotcrete 3D Printing (SC3DP) applies concrete layer by layer using a wet‐spray process. The resulting hardened concrete properties of the applied SC3DP layers (e.g. height, width or mechanical strength) are largely dependent on the selected material and process parameters. In this context, the nozzle geometry is an important influencing parameter. During printing, the velocity of the shotcrete jet is significantly influenced by the nozzle outlet diameter. Therefore, in the present study, the effect of the nozzle outlet diameter (15 ‐ 30 mm) is investigated with regard to the resulting layer homogeneity, i.e. local density and aggregate distribution in the cross‐section, and hardened concrete properties, i.e. flexural strength. By analysing the manufactured specimens, an uneven distribution of the aggregate is observed horizontally across the cross‐section of the layers. An accumulation of aggregate is present in the core of the layer resulting in a cement paste‐rich region in the edge areas. This leads to increased local densities in the core of the specimen. The application of the concrete with small nozzle outlet diameters results in the highest local densities and the highest flexural strength.
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Knopf, Julian P., Patrick R. Hof, and Helmut H. A. Oelschläger. "The Neocortex of Indian River Dolphins (Genus Platanista): Comparative, Qualitative and Quantitative Analysis." Brain, Behavior and Evolution 88, no. 2 (2016): 93–110. http://dx.doi.org/10.1159/000448274.
Full textAbstract:
We investigated the morphology of four primary neocortical projection areas (somatomotor, somatosensory, auditory, visual) qualitatively and quantitatively in the Indian river dolphins (Platanista gangetica gangetica, P. gangetica minor) with histological and stereological methods. For comparison, we included brains of other toothed whale species. Design-based stereology was applied to the primary neocortical areas (M1, S1, A1, V1) of the Indian river dolphins and compared to those of the bottlenose dolphin with respect to layers III and V. These neocortical fields were identified using existing electrophysiological and morphological data from marine dolphins as to their topography and histological structure, including the characteristics of the neuron populations concerned. In contrast to other toothed whales, the visual area (V1) of the ‘blind' river dolphins seems to be rather small. M1 is displaced laterally and the auditory area (A1) is larger than in marine species with respect to total brain size. The layering is similar in the cortices of all the toothed whale brains investigated; a layer IV could not be identified. Cell density in layer III is always higher than in layer V. The maximal neuron density in P. gangetica gangetica is found in layer III of A1, followed by layers III in V1, S1, and M1. The cell density in layer V is at a similar level in all primary areas. There are, however, some differences in neuron density between the two subspecies of Indian river dolphins. Taken as a whole, it appears that the neocortex of platanistids exhibits a considerable expansion of the auditory field. Even more than other toothed whales, they seem to depend on their biosonar abilities for navigation, hunting, and communication in their riverine habitat.
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Sasaki, H., K. Matsuno, A. Fujiwara, et al. "Distribution of Arctic and Pacific copepods and their habitat in the northern Bering Sea and Chukchi Sea." Biogeosciences Discussions 12, no. 22 (2015): 18661–91. http://dx.doi.org/10.5194/bgd-12-18661-2015.
Full textAbstract:
Abstract. The advection of warm Pacific water and the reduction of sea-ice extent in the western Arctic Ocean may influence the abundance and distribution of copepods, i.e., a key component in food webs. To understand the factors affecting abundance of copepods in the northern Bering Sea and Chukchi Sea, we constructed habitat models explaining the spatial patterns of the large and small Arctic copepods and the Pacific copepods, separately, using generalized additive models. Copepods were sampled by NORPAC net. Vertical profiles of density, temperature and salinity in the seawater were measured using CTD, and concentration of chlorophyll a in seawater was measured with a fluorometer. The timing of sea-ice retreat was determined using the satellite image. To quantify the structure of water masses, the magnitude of pycnocline and averaged density, temperature and salinity in upper and bottom layers were scored along three axes using principal component analysis (PCA). The structures of water masses indexed by the scores of PCAs were selected as explanatory variables in the best models. Large Arctic copepods were abundant in the water mass with high salinity water in bottom layer or with cold/low salinity water in upper layer and cold/high salinity water in bottom layer, and small Arctic copepods were abundant in the water mass with warm/saline water in upper layer and cold/high salinity water in bottom layers, while Pacific copepods were abundant in the water mass with warm/saline in upper layer and cold/high salinity water in bottom layer. All copepod groups were abundant in areas with deeper depth. Although chlorophyll a in upper and bottom layers were selected as explanatory variables in the best models, apparent trends were not observed. All copepod groups were abundant where the sea-ice retreated at earlier timing. Our study might indicate potential positive effects of the reduction of sea-ice extent on the distribution of all groups of copepods in the Arctic Ocean.
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Chen, Zhen, and Mingde Lang. "Research on Prospecting Prediction Based on Evidence Weight." Atmosphere 13, no. 12 (2022): 2125. http://dx.doi.org/10.3390/atmos13122125.
Full textAbstract:
There are many small and medium-sized orogenic copper deposits in the Jinman–Lanping area of Yunnan. In order to standardize mining, long-term planning, and unified management, it is necessary to further delineate prospecting areas. In order to improve the efficiency of prospecting, a data-driven approach is established. This paper uses the weight of evidence model to make prospecting predictions, and it then delineates the prospective prospecting area. The relevant evidence layers in the weight of evidence model are geochemical anomalies and remote sensing iron staining anomalies. Among them, the geochemical anomaly layer mainly uses the concentration-area (C-A) fractal model to separate the geochemical background and anomaly acquisition. The remote sensing iron-stained anomaly layer mainly uses bands (1, 4, 5, 7), and bands (1, 3, 4, 5) were combined for principal component analysis to extract abnormal iron staining. Finally, using the weight of evidence model, the spatial element layers (evidence layers) from different sources were combined, and the interaction between them was analyzed. It is pointed out that the area has good prospects for prospecting, and the prospective prospecting area was thus delineated.
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Agadjanian, A. K., M. V. Shunkov, and M. B. Kozlikin. "Taxonomic Composition of Small Vertebrates from the Pleistocene Deposits in the South Chamber of Denisova Cave." Problems of Archaeology, Ethnography, Anthropology of Siberia and Neighboring Territories 27 (2021): 7–11. http://dx.doi.org/10.17746/2658-6193.2021.27.0007-0011.
Full textAbstract:
The article presents the results of the study of small vertebrate bone remains from the Pleistocene deposits in the South Chamber of Denisova Cave. The taxonomic structure offossil communities was established by 10,842 bones from lithological layers 16-11. According to preliminary data, this part of the profile formed in the interval from the end of MIS 7 to the first half of MIS 3. The general paleogeographic assessment of the natural complexes of the Anui River valley indicates mosaic landscapes during the accumulation of layers 16-11. Taiga massifs alternated with areas of steppe and meadow biotopes. The river flow regime did not change fundamentally. Covering glaciers did not affect this region. Climatic fluctuations were reflected in the changing ratios of the dispersal areas of the forest, steppe, rocky and meadow biotopes. The general trend of climate and natural association changes was expressed in the gradual reduction offorest and expansion of steppe and meadow biotopes. The study of bone samples from the South Chamber showed that the preservation of paleontological material in the sediments in this part of the cave is somewhat better than in the taphocenoses of the Main and East Chambers. Better preservation of bones throughout the section makes it possible to refine the identification and supplement the taxonomic composition of small mammals. Analysis of the ground squirrel cheek teeth morphology from the deposits of layers 16, 15, 13, and 12 showed that they belong to the fossil red-cheeked ground squirrel Spermophillus erythrogenis palaeosibiricus. In the fossil record of layer 11, a form that predates the present-day field vole Microtus agrestis has been preserved, which indirectly indicates the time of the emergence of this taxon.
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Yang, Jing, Disheng Yi, Bowen Qiao, and Jing Zhang. "Spatio-Temporal Change Characteristics of Spatial-Interaction Networks: Case Study within the Sixth Ring Road of Beijing, China." ISPRS International Journal of Geo-Information 8, no. 6 (2019): 273. http://dx.doi.org/10.3390/ijgi8060273.
Full textAbstract:
Spatial-interaction networks are an important factor in geography that could help in the exploration of both human spatial-temporal behavior and the structure of urban areas. This paper analyzes changes in the spatio-temporal characteristics of the Spatial-Interaction Networks of Beijing (SINB) in three consecutive steps. To begin with, we constructed 24 sequential snapshots of spatial population interactions on the basis of points of interest (POIs) collected from Dianping.com and various taxi GPS data in Beijing. Then, we used Jensen–Shannon distance and hierarchical clustering to integrate the 24 sequential network snapshots into four clusters. Finally, we improved the weighted k-core decomposition method by combining the complex network method and weighted distance in a geographic space. The results showed: (1) There are three layers in the SINB: a core layer, a bridge layer, and a periphery layer. The number of places greatly varies, and the SINB show an obvious hierarchical structure at different periods. The core layer contains fewer places that are between the Second and Fifth Ring Road in Beijing. Moreover, spatial distribution of places in the bridge layer is always in the same location as that of the core layer, and the quantity in the bridge layer is always superior to that in the core layer. The distributions of places in the periphery layer, however, are much greater and wider than the other two layers. (2) The SINB connected compactly over time, bearing much resemblance to a small-world network. (3) Two patterns of connection, each with different connecting ratios between layers, appear on weekdays and weekends, respectively. Our research plays a vital role in understanding urban spatial heterogeneity, and helps to support decisions in urban planning and traffic management.
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Bortfeldt, Jonathan. "Construction and Test of Full-Size Micromegas Modules for the ATLAS New Small Wheel Upgrade." EPJ Web of Conferences 174 (2018): 01003. http://dx.doi.org/10.1051/epjconf/201817401003.
Full textAbstract:
In 2015 the first full size resistive-strip Micromegas modules for the ATLAS New Small Wheel upgrade will be realized. The goal is to provide precision muon tracking with spatial resolution below 100 μm on trapezoidal four-layer detector modules with areas between 2 and 3 m2. This poses stringent limits on the overall accuracy of the modules with respect to strip positioning and planarity. Each module is built as a quadruplet of four resistive strip Micromegas layers, constructed from stiff sandwich panels. An assembly procedure has been developed to build the panels and modules with the required mechanical precision of 30 μm along the precision coordinate and 80 μm perpendicular to the chamber. The construction and quality assurance procedures ensure good module quality verified by checks done during the construction and the chamber assembly.
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Mignot, J., C. de Boyer Montégut, and M. Tomczak. "On the porosity of barrier layers." Ocean Science 5, no. 3 (2009): 379–87. http://dx.doi.org/10.5194/os-5-379-2009.
Full textAbstract:
Abstract. Barrier layers are defined as the layer between the pycnocline and the thermocline when the latter are different as a result of salinity stratification. We present a revisited 2-degree resolution global climatology of monthly mean oceanic Barrier Layer (BL) thickness first proposed by de Boyer Montégut et al. (2007). In addition to using an extended data set, we present a modified computation method that addresses the observed porosity of BLs. We name porosity the fact that barrier layers distribution can, in some areas, be very uneven regarding the space and time scales that are considered. This implies an intermittent alteration of air-sea exchanges by the BL. Therefore, it may have important consequences for the climatic impact of BLs. Differences between the two computation methods are small for robust BLs that are formed by large-scale processes. However, the former approach can significantly underestimate the thickness of short and/or localized barrier layers. This is especially the case for barrier layers formed by mesoscale mechanisms (under the intertropical convergence zone for example and along western boundary currents) and equatorward of the sea surface salinity subtropical maxima. Complete characterisation of regional BL dynamics therefore requires a description of the robustness of BL distribution to assess the overall impact of BLs on the process of heat exchange between the ocean interior and the atmosphere.
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Barošová, Ivana, Markéta Šantrůčková, Pavel Matiska, and Adam Baroš. "Ornamental perennials in small rural settlements: a case study from the Czech Republic." Horticultural Science 47, No. 2 (2020): 130–38. http://dx.doi.org/10.17221/21/2019-hortsci.
Full textAbstract:
The history of a site includes not only preserved historical buildings, but also areas with an assortment of plants, which have been preserved for many years. Rural settlements make up 80% of all the municipalities in the Czech Republic, with greenery covering 50–70% of their area. There are dominant trees and shrubs and an herb layer. The herb layer has high species diversity and species typical of the area, but at the same time, its long-term survival is in jeopardy. The continuity of rural settlements has been disturbed since the second half of the 20th century. Rural spaces often become uniform and impersonal, without links to the surrounding countryside, traditions, and history. This study included a total of 124 perennial families within three studied regions.
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Grytsevych, N. R., and V. V. Vereschaka. "Influence of portal hypertension on the state of the hemomicrocirculatory level of rat skin: morphological study." Fiziolohichnyĭ zhurnal 67, no. 3 (2021): 45–53. http://dx.doi.org/10.15407/fz67.03.045.
Full textAbstract:
The effect of portal hypertension on the condition of the hemomicrocirculatory tract of the skin male white nonlinear rats was studied. Hypertension was simulated by applying a ligature to the portal vein according to the conventional method. After 30, 60 and 90 days, skin biopsies were taken from the anterior abdominal wall for optical microscopy examination, which was subjected to routine histological processing. In animals of the control group, which underwent sham surgery, the skin remained unchanged. In rats of the experimental group after 30 days in the basal layer of the epidermis there were cells with signs of degenerative changes. The basement membrane of the epidermis had small areas with thinning and thickening, which in both cases were accompanied by the formation of small and massive leukocyte infiltrates. Its edema was noted, which extended to the papillary and reticular layer of the dermis. Elastic fibers were unchanged. Only 50% of the microvessels looked intact, 20% microvessels were narrowed, and 30% had signs of stagnant hyperemia due to dilatation. After 60 days the epidermis was thinned, in the basal layer the cells with picnotized and displaced to the periphery nucleus were detected. In all studied layers of epidermis, besides reticular layer, expansion of arterioles, venules and capillary loops was observed. After 90 days the epidermis was represented by 3-6 layers of cells, its general refinement was observed due to the reduction of the thickness of the spinous and granular layers with simultaneous thickening of the horny layer. In the papillary layer of the dermis, the number of thin-walled blood vessels was increased. The average diameter of the arterioles of the hypodermis decreased relative to the values on the 60th day. The mean diameter of the arterioles of the subdermal network on the border of the papillary and reticular layers and capillary loops under the basal membrane was reduced what can be a sign of sclerotic changes in the microvessels. The venules diameter remained increased. In arterioles and venules, stasis of the microvessels, edema of their walls, microaneurysm, and venous sacculation were detected. Thus, we believe that the changes in the microvessels of the skin, which are observed in portal hypertension, are the result of hemodynamic disturbances in the tissue, which is a complex chain of hemomicrocirculatory flow to the direct action of hypertension in the portal vein and is a secondary response to systemic vascular damage.
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Yu, Zhihui, Nian Pan, and Jin Zhou. "SFFNet: Shallow Feature Fusion Network Based on Detection Framework for Infrared Small Target Detection." Remote Sensing 16, no. 22 (2024): 4160. http://dx.doi.org/10.3390/rs16224160.
Full textAbstract:
Infrared small target detection (IRSTD) is the process of recognizing and distinguishing small targets from infrared images that are obstructed by crowded backgrounds. This technique is used in various areas, including ground monitoring, flight navigation, and so on. However, due to complex backgrounds and the loss of information in deep networks, infrared small target detection remains a difficult undertaking. To solve the above problems, we present a shallow feature fusion network (SFFNet) based on detection framework. Specifically, we design the shallow-layer-guided feature enhancement (SLGFE) module, which guides multi-scale feature fusion with shallow layer information, effectively mitigating the loss of information in deep networks. Then, we design the visual-Mamba-based global information extension (VMamba-GIE) module, which leverages a multi-branch structure combining the capability of convolutional layers to extract features in local space with the advantages of state space models in the exploration of long-distance information. The design significantly extends the network’s capacity to acquire global contextual information, enhancing its capability to handle complex backgrounds. And through the effective fusion of the SLGFE and VMamba-GIE modules, the exorbitant computation brought by the SLGFE module is substantially reduced. The experimental results on two publicly available infrared small target datasets demonstrate that the SFFNet surpasses other state-of-the-art algorithms.