Relative Height Changes Research Articles

Numerical Investigation on the Effect of Height-to-Radius Ratio on Flow Separation Features in S-Shaped Diffuser with Boundary Layer Ingestion

The flow separation occurring in the S-shaped diffuser with boundary layer ingestion (BLI) has a significant effect on the performance of the embedded engine. Previous studies have found that the area ratio (AR) as well as the length-to-offset ratio (LOR) of the S-shaped diffuser are the key contributing factors that affect the flow separation features. Based on the flow phenomena observed in previous studies of an S-shaped diffuser with 100% BLI, a hypothesis that the parameter height-to-radius ratio (HRR) may also have significant effect on the flow separation features in the S-shaped diffuser is proposed. The purpose of this paper is to verify this hypothesis and to further investigate the effect of HRR on the flow separation features in the S-shaped diffuser with BLI using numerical methods. First, the hypothesis that HRR has an effect on the flow separation features in the S-shaped diffuser is verified under uniform inlet condition. Second, the effect of HRR on the flow separation features is investigated under different relative heights of inlet BLI. It is found that the flow separation features in the S-shaped diffuser are very sensitive to the change in HRR but not to the change in relative height of inlet BLI. Finally, for the fixed boundary layer height generated from the airframe, the S-shaped diffuser with a smaller design HRR can significantly suppress the flow separation and thus achieve a higher total pressure recovery and a lower distortion coefficient. The results provide improved understandings of the factor affecting the flow separation features in the S-shaped diffuser, and are useful for improving the aerodynamic performance of the embedded engine with BLI.

Growth, morphology, and biomass allocation of recently planted seedlings of seven European tree species along a light gradient

Light is one of the most critical factors controlling tree survival and growth. Limited light availability induces phenotypic plasticity, thus enabling plants to adapt to suboptimal conditions. The plastic responses are species-specific and are thought to largely depend on species’ shade tolerance. This study aims to add to existing research by trying to disentangle the effects of light, species identity, and shade tolerance on growth, biomass partitioning, and morphology of seedlings of seven common European tree species. For that purpose, we set up a shading experiment where seedlings were grown under three levels of light availability (15%, 35%, and 100%). A destructive harvest was carried out for the assessment of biomass allocation and structural complexity of plant architecture after a year of exposure to limited light. The specific leaf area increased with decreasing light availability for all species. However, we found little to no changes in relative height and diameter growth, biomass allocation to aboveground tree compartments, and structural complexity along the light gradient. We argue that because trees were grown under open field conditions, both in the nursery and for the first year of the experiment, it might have resulted in a delayed response to limited light availability. Assuming the delayed reaction of less plastic plant organs, we expect that the morphological adaptations of the tree species and intra- and interspecific differences will become more pronounced, as the trees grow older.

P57 Continuous drug delivery is significantly affected by relative height changes between patient and syringe driver

AimsSyringe drivers are the principle method of giving continuous infusions of important drugs to patients. Many of these drugs are critical for the maintenance of normal physiology. Anecdotal evidence abounds of severe patient instability on movement of syringe drivers during infusion. Our objective was to define the variation in drug delivery seen in three different syringe drivers, with changes in relative height between the syringe driver and the end of the giving set.MethodsThree syringe drivers (Alaris CC (Becton Dickinson), Perfusor Space (B Braun), and Synamed μSP6000 (Arcomed)) were analysed for reliability of flow at 0.5, 1, 2, and 5 ml/hr. A small air bubble was introduced into the giving set, and the progression of this was documented before and after a vertical movement of the syringe driver by 25 or 50 cm upwards or downwards relative to the delivery port.ResultsFor all pumps, delivery was interrupted on movement of the pumps downwards, and a bolus was given with movement of the pump upwards. Delivery halted at lower pump speeds for longer than higher pump speeds. The maximum delivery interruption was 11.8 minutes. Boluses given on moving the pump up were calculated as the equivalent number of minutes needed to deliver the bolus volume at steady state. The maximum bolus given was equivalent to 15.8 minutes of delivery. We were unable to eliminate the effects seen by very slow, steady movement of the pumps up or down. Static height differences made no difference to delivery.ConclusionsSyringe drivers should not be moved vertically in relation to the patient. Critical drug delivery is interrupted for up to 12 minutes with relative downward movements, and significant boluses of drugs are given with relative upward movements. As far as possible, elimination of relative height movements is advised, and extreme caution is necessary if any movements are unavoidable.

Continuous Drug Delivery is Significantly Affected by Relative Height Changes Between Patient and Syringe Driver.

Syringe drivers are the principle method of giving small-volume continuous infusions of important drugs to patients. Many of these drugs are critical for the maintenance of normal physiology. Anecdotal evidence abounds of severe patient instability on movement of syringe drivers during infusion. We aimed to define the variation in drug delivery seen in three syringe drivers, with changes in relative height between the syringe driver and the end of the giving set. Three syringe drivers (Alaris CC [Becton Dickinson], Perfusor Space [B Braun], and Synamed μSP6000 [Arcomed]) were analyzed for reliability of flow at 0.5, 1, 2, and 5 mL/h. This is an in vitro investigation. A small air bubble was introduced into the giving set, and the progression of this was documented before and after a vertical movement of the syringe driver by 25 or 50 cm upward or downward relative to the delivery port. For all pumps, delivery was interrupted on movement of the pumps downward, and a bolus was given with movement of the pump upward. Delivery halted at lower pump speeds for longer than higher pump speeds. The maximum delivery interruption was 11.8 minutes. Boluses given on moving the pump up were calculated as the equivalent number of minutes needed to deliver the bolus volume at steady state. The maximum bolus given was equivalent to 15.8 minutes of delivery. We were unable to eliminate the effects seen by very slow, steady movement of the pumps up or down. Static height differences made no difference to delivery. Syringe drivers should not be moved vertically in relation to the patient. Critical drug delivery is interrupted for up to 12 minutes with relative downward movements, and significant boluses of drugs are given with relative upward movements. As far as possible, elimination of relative height movements is advised, and extreme caution is necessary if any movements are unavoidable.

Changes in Relative Height of Children in Northeast Asian Countries in Fifty Years Since 1960

Changes in Relative Height of Children in Northeast Asian Countries in Fifty Years Since 1960

Secular Changes in Relative Height of Children in Japan, South Korea and Taiwan: Is “Genetics” the Key Determinant?

Secular Changes in Relative Height of Children in Japan, South Korea and Taiwan: Is “Genetics” the Key Determinant?

Quality Evaluation of the Earth’s Crust Height Movement Kinematic Model in the Northern Part of the Republic of Croatia

The focus of this paper is the quality evaluation of the relative height movement kinematic model of the Earth’s crust that covers the territory of the Republic of Croatia. This model offers necessary data for the calculation of relative vertical displacements and moving speed of Earth’s crust discrete points. Consequentially it can be used for reductions in direct levelling measurements from their surveying epoch to another chosen epoch by the elimination of relative height movement effects. As the quality of the model is not yet unambiguously analysed and determined this paper offers kinematic model quality analysis on the northern part of the Croatian territory. In this area, an indirect quality assessment method is used based on levelling measurements accuracy investigation. The measurements accuracy is determined in levelling networks of the 2nd order that almost completely cover the northern part of Croatia. Original levelling measurements from precise levelling network (2nd order state networks) are corrected for the systematic effect of benchmark’s relative height movements and reduced from their original survey epochs to the mean epoch of so-called Second High Accuracy Levelling Network (1st order state network). Precise levelling network is investigated simultaneously at the level of original and reduced measurements, comparing “a prior” and “a posterior” measurements accuracy criteria. The result suggests more or less successful elimination of the systematic effect of crustal relative height movements from the levelling measurements. Furthermore, the results confirm the hypothesis that the kinematic model can be reliably used for the determination of regional relative height changes and regional trends in crustal movements within the centimetre level of accuracy.

In Situ Dilatometric Study of the Binder Influence on the Electrochemical Intercalation of Bis(trifluoromethanesulfonyl) imide Anions into Graphite

Dual-ion or dual-graphite batteries based on the mechanism of electrochemical anion intercalation into a graphite cathode have become attractive as an alternative storage technology in recent years. Due to large volume changes of the graphite particles during electrochemical anion intercalation, an appropriate electrode binder is required to sustain the mechanical integrity of the composite electrode and a stable and highly reversible charge/discharge cycling. Therefore, the expansion and contraction behavior of graphite positive electrodes containing different binders, including Na-carboxymethyl cellulose (CMC), poly(vinylidene)difluoride (PVdF) and a CMC/styrene butadiene rubber (SBR) mixture, during anion intercalation/de-intercalation was investigated by in situ electrochemical dilatometry (ECD). These measurements give insights into reversible and irreversible relative height changes at different cycling conditions and, thus, into the long-term cycling stability of the composite electrodes.Long-term cycling measurements reveal that the maximum and minimum electrode thicknesses of PVdF-based electrodes remain constant during anion intercalation/de-intercalation, while the CMC-containing electrodes exhibit a thickness increase in the first cycles and subsequent decrease after reaching a maximum electrode thickness. This instability can most likely be correlated with the mechanical instability of the electrode due to the high stiffness of the CMC binder compared to PVdF and an active material contact loss during cycling. If CMC is applied as binder mixture in combination with SBR, which shows a high flexibility, the thickness decay can be decreased. Our results give new insights into the optimization potentials of composite electrodes for carbon-based cathodes in dual-ion cells that experience large volume expansion during cycling.

Laboratory measurements of remote sensing reflectance of selected phytoplankton species from the Baltic Sea

Results of unique laboratory measurements of remote sensing reflectance (Rrs) of several phytoplankton species typically occurring in high abundances in the Baltic Sea waters are presented. Reflectance spectra for diatoms: Cyclotella meneghiniana and Skeletonema marinoi and cyanobacteria: Dolichospermum sp., Nodularia spumigena and Synechococcus sp. were analysed in terms of assessment of their characteristic features and the differences between them. These species contain similar pigments, which results in general similarities of reflectance spectra, i.e. decrease of reflectance magnitude in the blue and red spectrum regions. However, hyper-spectral resolution of optical measurements let us find differences between optical signatures of diatoms and cyanobacteria groups and between species belonging to one group as well. These differences are reflected in location of local maxima and minima in the reflectance spectrum and changes in relative height of characteristic peaks with changes of phytoplankton concentration. Wide ranges of phytoplankton concentrations were analysed in order to show the persistence of Rrscharacteristic features. The picoplankton species, Synechococcus sp. show the most distinct optical signature, which let to distinguish separate cluster in hierarchical cluster analysis (HCA). The results can be used to calibrate input data into radiative transfer model, e.g. phase function or to validate modelled Rrsspectra.

Diffraction phase microscopy imaging and multi-physics modeling of the nanoscale thermal expansion of a suspended resistor

We studied the nanoscale thermal expansion of a suspended resistor both theoretically and experimentally and obtained consistent results. In the theoretical analysis, we used a three-dimensional coupled electrical-thermal-mechanical simulation and obtained the temperature and displacement field of the suspended resistor under a direct current (DC) input voltage. In the experiment, we recorded a sequence of images of the axial thermal expansion of the central bridge region of the suspended resistor at a rate of 1.8 frames/s by using epi-illumination diffraction phase microscopy (epi-DPM). This method accurately measured nanometer level relative height changes of the resistor in a temporally and spatially resolved manner. Upon application of a 2 V step in voltage, the resistor exhibited a steady-state increase in resistance of 1.14 Ω and in relative height of 3.5 nm, which agreed reasonably well with the predicted values of 1.08 Ω and 4.4 nm, respectively.

Estimation of height changes of GNSS stations from the solutions of short vectors and PSI measurements

Abstract Time series of weekly and daily solutions for coordinates of permanent GNSS stations may indicate local deformations in Earth’s crust or local seasonal changes in the atmosphere and hydrosphere. The errors of the determined changes are relatively large, frequently at the level of the signal. Satellite radar interferometry and especially Persistent Scatterer Interferometry (PSI) is a method of a very high accuracy. Its weakness is a relative nature of measurements as well as accumulation of errors which may occur in the case of PSI processing of large areas. It is thus beneficial to confront the results of PSI measurements with those from other techniques, such as GNSS and precise levelling. PSI and GNSS results were jointly processed recreating the history of surface deformation of the area of Warsaw metropolitan with the use of radar images from Envisat and Cosmo-SkyMed satellites. GNSS data from Borowa Gora and Jozefoslaw observatories as well as from WAT1 and CBKA permanent GNSS stations were used to validate the obtained results. Observations from 2000–2015 were processed with the Bernese v.5.0 software. Relative height changes between the GNSS stations were determined from GNSS data and relative height changes between the persistent scatterers located on the objects with GNSS stations were determined from the interferometric results. The consistency of results of the two methods was 3 to 4 times better than the theoretical accuracy of each. The joint use of both methods allows to extract a very small height change below the level of measurement error.

REFINEMENT OF STEREO IMAGE ANALYSIS USING PHOTOMETRIC SHAPE RECOVERY AS AN ALTERNATIVE TO BUNDLE ADJUSTMENT

Topographic mapping, e.g. the generation of Digital Elevation Models (DEM), is of general interest to the remote sensing community and scientific research. Commonly, photogrammetric methods, e.g. stereo image analysis methods (SIAM) or bundle adjustment methods (BAM), are applied to derive 3D information based on multiple images of an area. These methods require the detection of control points, i.e. common points within multiple images, which relies on a similarity measure and usually yields a sparse map of 3D points. The full spatial DEM is then obtained by interpolation techniques or imposed restrictions, e.g. smoothness constraints. Since BAM utilizes all images of the area, it is assumed to provide a more accurate DEM than SIAM which utilizes only pairs of images. Intensity-based shape recovery, e.g. shape from shading (SfS), utilizes the reflectance behavior of the object surface and thus provides a dense map of relative height changes, which provide the possibility to refine the photogrammetric DEMs. Based on Rosetta NavCam images of 67P/Churyumov-Gerasimenko we compare intensity-based DEM refinement methods which use DEMs obtained based on SIAM and BAM as a reference. We show that both the SIAM based DEM refinement and the BAM based DEM refinement are of similar quality. It is thus possible to derive DEMs of high lateral resolution by applying the intensity-based refinement to the less complex SIAM.

REFINEMENT OF STEREO IMAGE ANALYSIS USING PHOTOMETRIC SHAPE RECOVERY AS AN ALTERNATIVE TO BUNDLE ADJUSTMENT

Abstract. Topographic mapping, e.g. the generation of Digital Elevation Models (DEM), is of general interest to the remote sensing community and scientific research. Commonly, photogrammetric methods, e.g. stereo image analysis methods (SIAM) or bundle adjustment methods (BAM), are applied to derive 3D information based on multiple images of an area. These methods require the detection of control points, i.e. common points within multiple images, which relies on a similarity measure and usually yields a sparse map of 3D points. The full spatial DEM is then obtained by interpolation techniques or imposed restrictions, e.g. smoothness constraints. Since BAM utilizes all images of the area, it is assumed to provide a more accurate DEM than SIAM which utilizes only pairs of images. Intensity-based shape recovery, e.g. shape from shading (SfS), utilizes the reflectance behavior of the object surface and thus provides a dense map of relative height changes, which provide the possibility to refine the photogrammetric DEMs. Based on Rosetta NavCam images of 67P/Churyumov-Gerasimenko we compare intensity-based DEM refinement methods which use DEMs obtained based on SIAM and BAM as a reference. We show that both the SIAM based DEM refinement and the BAM based DEM refinement are of similar quality. It is thus possible to derive DEMs of high lateral resolution by applying the intensity-based refinement to the less complex SIAM.

SARAL/AltiKa Altimetry Data for Monitoring of Inland Water Body: a Case Study of Mayurakshi Reservoir, India

Present study aims at monitoring of water levels for Mayurakshi reservoir (~68 sq. km) located in the Jharkhand state, India using Geophysical Data Records (GDR) data from SARAL/AltiKa launched in February, 2013. Reservoir water levels for the period April, 2013 to December 2014 were derived from space using SARAL/AltiKa data. The absolute average difference, standard deviation and the Root Mean Square Error (RMSE) between altimetric data and gauge readings were 0.49, 0.29 and 0.56 m respectively. The accuracy of the relative water levels ranges between 0.008 and 0.8 m with a mean of 0.34 m, standard deviation of 0.27 m and RMSE of 0.44 m. Resulting time series of relative height changes and the amplitude variations are identical for most of the study period except during low stage, linked to the fact that some reservoir waveforms are season dependent. The results highlight the applicability of the SARAL/AltiKa data for monitoring small to medium reservoirs having surface area less than 100 sq. km.

In-Situ Atomic Force Microscopy Studies of Ti3C2: A Promising New Material for Electrochemical Capacitors

MXenes are a newly discovered class of two-dimensional materials prepared through extraction of metals such as Al from MAX phases, whose general formula is Mn+1AXn, where M is an early transition metal, A an A-group element, and X is carbon and/or nitrogen.[1-3] Ti3C2 is one member of this MXene family which is capable of capacitances of up to 350 F cm-3, making this an attractive material for electrochemical capacitors.[4] The high storage capacity of this material is attributed to rapid intercalation of electrolyte ions within the layered structure [Figure 1a]. In this work we use in-situ atomic force microscopy (AFM) to probe the macroscopic expansion of Ti3C2 during electrochemical cycling. The in-situ electrochemical AFM cell used for this study as well as the relative height change of a Ti3C2 electrode in 1 M KOH electrolyte are shown in Figures 1b and c. During negative polarization of the material K+ ions are incorporated into the Ti3C2 structure associated with a macroscopic expansion of the electrode. Studies are performed on various Ti3C2 electrodes in several electrolytes to determine the effect of different ions and electrode structure on the electrochemical behavior and observed strain response.

Large Electrically Induced Height and Volume Changes in Poly(3,4-ethylenedioxythiophene)/Poly(styrenesulfonate) Thin Films

We demonstrate large, partly reversible height and volume changes of thin films of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) on the anode of interdigitating gold electrodes under ambient conditions by applying an electrical bias. The height and volume changes were monitored with optical and atomic force microscopy and are found to be independent of initial film thickness. In the first cycle, a relative height change of 950% is observed for a 21 nm thick film. Two regimes are identified. In the first regime, reversible redox reactions occur and reversible height changes can be ascribed to absorption of water via osmotic effects, brought about by an increasing ion concentration on the anode. In the second, irreversible regime, irreversible overoxidation of the PEDOT occurs and mass transport from the channel to the anode becomes important.

Distinct Variants at LIN28B Influence Growth in Height from Birth to Adulthood

We have studied the largely unknown genetic underpinnings of height growth by using a unique resource of longitudinal childhood height data available in Finnish population cohorts. After applying GWAS mapping of potential genes influencing pubertal height growth followed by further characterization of the genetic effects on complete postnatal growth trajectories, we have identified strong association between variants near LIN28B and pubertal growth (rs7759938; female p = 4.0 x 10(-9), male p = 1.5 x 10(-4), combined p = 5.0 x 10(-11), n = 5038). Analysis of growth during early puberty confirmed an effect on the timing of the growth spurt. Correlated SNPs have previously been implicated as influencing both adult stature and age at menarche, the same alleles associating with taller height and later age of menarche in other studies as with later pubertal growth here. Additionally, a partially correlated LIN28B SNP, rs314277, has been associated previously with final height. Testing both rs7759938 and rs314277 (pairwise r(2) = 0.29) for independent effects on postnatal growth in 8903 subjects indicated that the pubertal timing-associated marker rs7759938 affects prepubertal growth in females (p = 7 x 10(-5)) and final height in males (p = 5 x 10(-4)), whereas rs314277 has sex-specific effects on growth (p for interaction = 0.005) that were distinct from those observed at rs7759938. In conclusion, partially correlated variants at LIN28B tag distinctive, complex, and sex-specific height-growth-regulating effects, influencing the entire period of postnatal growth. These findings imply a critical role for LIN28B in the regulation of human growth.

Commentary: Height and intelligence

Commentary: Height and intelligence

Interfacial sliding in Cu/Ta/polyimide high density interconnects as a result of thermal cycling

A scanning probe microscope was used to observe thermally induced deformation of 1 μm thick Cu/Ta/polyimide test structures on Si. Relative height changes in arrays of parallel Cu and polyimide lines of various aspect ratios were examined in air at room temperature before and after a 25-350-25°C thermal cycle conducted in gettered nitrogen. Grain elevation and hillock formation at grain boundaries were observed on the Cu surface as a result of the thermal cycling. It was also observed that significant sliding occurs at the Cu/Ta interface with 1 μm wide Cu lines. Less or no sliding was observed at the interface with 10 μm wide Cu lines.

Thermomechanical deformation of 1 μm thick Cu-polyimide line arrays studied by scanning probe microscopy

Due to the lower dielectric constant than the currently used SiO2 dielectric, several polyimides are being considered for use in multi-layer high density interconnects. However, the mismatch in out-of-plane coefficient of thermal expansion (CTE) between the Cu conductor and most spin-coated polyimides may cause interfacial failures. A scanning probe microscope was used to estimate the out-of-plane CTE for several 1 μm thick, spin-coated polyimides and to observe thermally induced deformation of Cu-polyimide test structures on Si. The change in relative height of arrays of parallel Cu and polyimide lines of various aspect ratios were imaged in air at room temperature and 97°C. Linear elastic, generalized plane strain finite element models for different out-of-plane CTEs were used to estimate the CTE from the profile changes. It was observed that narrow (≤1 μm) polyimide lines are more constrained from expansion than wider lines.