Line Positions Research Articles

Coordinates transformation method for pointer gauge reading by machine vision

In this report we present a machine vision algorithm for pointer gauge reading based on coordinates transformation. Since a pointer gauge is a polar representation of a linear scale, it is possible to transform its polar reading to the original linear counterpart. Once the picture of a pointer gauge is captured digitally, we can assign the polar positions to each pixel of the image. Those polar coordinates can be plotted on a rectangular frame to form a transformed image. The scale lines and the pointer are transformed to point vertically (or horizontally). Locations of the scale lines and pointer can be obtained from their pixel histograms maxima. The main advantage of our algorithm is its simplicity. We can read the pointer orientation and scale lines position of a pointer gauge directly from its geometrical structure. The complication of feature extraction process from the conventional algorithm, e.g., Hough transformation, can be avoided. We have tested the algorithm with the ideal and real image of pointer gauges. In the latter case, even though there are some noises on the transformed image, the locations of pointer and scale lines can still be easily found. Due to its simplicity, our algorithm is fast. We expect that our method can be useful in practice as an alternative machine vision algorithm when the real time pointer gauge reading system, e.g., the automatic dial gauge tester, is needed.

The high resolution absorption spectrum of methane in the 10 800-14 000 cm-1 region: literature review, new results and perspectives.

The recent development of high resolution spectrographs for exoplanetary research in the visible range makes suitable an improvement of our knowledge of the high resolution spectrum of methane. In this contribution, the weak and highly congested absorption spectrum of methane in the 10 800-14 000 cm-1 region (0.71-0.93 μm) is considered on the basis of (i) an exhaustive review of the literature over the lasts decades, (ii) the analysis of a spectrum recorded at Kitt Peak by Fourier transform spectroscopy at room temperature, (iii) a very high sensitivity spectrum recorded by cavity ring down spectroscopy near 760 nm. The line list retrieved from the Kitt Peak spectrum includes 12 800 lines between 10 802 and 13 922 cm-1. Together with the CRDS line list in the 13 060-13 300 cm-1 interval (about 2650 lines), the reported FTS dataset represents the first high resolution extensive intensity measurements of methane for wavenumbers above 11 502 cm-1. A very good agreement between our Kitt Peak line list and HITRAN list is found in the 10 800-11 502 cm-1 interval. The "quasi-continuum" absorption background underlying the congested spectrum around 11 200 cm-1 is quantitatively evaluated to about 42% of the absorption by CH4 lines. Previous laser-based investigations are critically reviewed by comparison to the FTS and CRDS experimental data retrieved in the present work. The review of the studies of the minor isotopologues (13CH4, CH3D, CH2D2, and CHD3) is also presented. Intensity comparison with band models used for planetary applications is discussed and confirms the importance of the "quasi-continuum" absorption in the methane spectrum at room temperature. The comparison to the TheoReTs line list obtained by ab initio calculations gives valuable hints for future assignments but the TheoReTS line positions are not sufficiently accurate for application to high resolution exoplanetary spectra in the region. From the various comparisons and results obtained in this work, we conclude that the high frequency absorption spectrum of methane deserves to be revisited by modern cavity-enhanced absorption techniques to fulfil needs both for future analysis of high resolution exoplanetary spectra and for theoretical analysis.

Waveguide Analysis of Radiofrequency Transmission in Well Tubulars for Electromagnetic Heating of Heavy Oil

This paper presents the numerical modelling and simulation of a 2D vertical well tubular model excited by a coaxial radiofrequency transmission line placed in its annular space for the purpose of downhole RF energy transmission. The study identifies the mechanism of energy losses due to coupling between the transmission line and steel tubing and casing using resonance mode analysis. The design of a left-handed artificial power line is proposed to minimize the losses due to the right-handed properties of the coaxial transmission line. The design utilizes ideal lumped element method to determine the left-handedness of the right-handed coaxial transmission line over the industrial heating radio-frequency band. The model is developed and simulated using COMSOL multi-physics commercial simulation software. The effect of transmission line position within the annular space on the tangential magnetic field and resulting power losses along the tubing is discussed. It is observed that the resulting artificial power line improves RF power transmission over 60 m depths of the vertical oil well within the industrial heating radiofrequency band.

Infrared action spectroscopy of the deprotonated formic acid trimer, trapped in helium nanodroplets.

Hydrogen bonding interactions are essential in the structural stabilization and physicochemical properties of complex molecular systems, and carboxylic acid functional groups are common participants in these motifs. Consequently, the neutral formic acid (FA) dimer has been extensively investigated in the past, as it represents a useful model system to investigate proton donor-acceptor interactions. The analogous deprotonated dimers, in which two carboxylate groups are bound by a single proton, have also served as informative model systems. In these complexes, the position of the shared proton is mainly determined by the proton affinity of the carboxylate units. However, very little is known about the nature of the hydrogen bonding interactions in systems containing more than two carboxylate units. Here we report a study on the deprotonated (anionic) FA trimer. IR spectra are recorded in the 400-2000 cm-1 spectral range by means of vibrational action spectroscopy of FA trimer ions embedded in helium nanodroplets. Characterization of the gas-phase conformer and assignment of the vibrational features is achieved by comparing the experimental results with electronic structure calculations. To assist in the assignments, the 2H and 18O FA trimer anion isotopologues are also measured under the same experimental conditions. Comparison between the experimental and computed spectra, especially the observed shifts in spectral line positions upon isotopic substitution of the exchangeable protons, suggests that the prevalent conformer, under the experimental conditions, exhibits a planar structure that resembles the crystalline structure of formic acid.

An Aberrant Position of Peripherally Inserted Central Venous Catheter in Extreme Preterm Infant

The use of a Percutaneously inserted central catheter (PICC) has increased with improved survival of extremely premature infants. Catheter malposition and perforation are associated with serious complications. PICC line position always needs to be confirmed after insertion. An Anteroposterior (AP) view radiograph is commonly used to confirm catheter tip position. We report a case of an unusual PICC position despite confirmation of the PICC tip position on the AP view radiograph. It is a potentially fatal complication and timely intervention can be lifesaving. Performing lateral X-rays to confirm the PICC tip or USG-guided placement of the catheter tip can prevent untoward serious complications. In the case of ascites, upper-extremity catheter insertion should be preferred instead of lower-extremity central venous catheters.

Refining Orbits of Bright Binary Systems

We obtained spectra of several bright binary systems (ζ02 UMa, 2 Lac, and ϕ Aql), which were mostly observed with photographic plates and whose orbits were not determined very accurately. Each system was monitored for a few years with the 81-cm telescope equipped with an échelle spectrograph at the Three College Observatory in North Carolina. The spectra were taken in a wavelength range between 4000 and 7900 Å with a spectral resolution of R∼ 12,000. Radial velocity measurements were done using cross-correlation in selected spectral regions or by measuring positions of individual spectral lines. Refined orbits and stellar parameters are presented.

Growth Analyses of Dipterocarpaceae Stand on Selective Cutting and Line Planting Silvicultural System with Different Planting Line Direction in North Kalimantan

The potency of the Indonesian Tropical Forest, particularly in Kalimantan, has been shrinkage year by year. Selective Cutting and Line Planting System (SCLP) is expected to increase the productivity of the tropical forest. This study aims to analyze the growth and diameter increment of Dipterocarpaceae stand planted in West-East (W-E) and North-South (N-S) planting direction on SCLP at concession area of PT. Intracawood Manufacturing, Bulungan District, North Kalimantan, Indonesia. Growth and diameter increment data of Dipterocarpaceae was obtained by field measurement in 4 (four) permanent plots sized 100 m x 100 m with W-E and N-S directions. The study revealed that the largest growth and average diameter increment on a five-year-old stand is Shorea parvifolia with planting direction of W-E about 8,5 cm and 1,92 cm/yr. In contrast, the smallest is Dryobalanops lanceolata with N-S planting direction about 4,6 cm and 0,99 cm/yr. Planting line direction does not influence diameter increment. It is due to the stand position in the spacing line as an ex-cutting area or the right and left-hand sides of the planting line with low density and low average stand height (17,62 m). Therefore, the light intensity on the N-S planting line direction has no barrier of spacing line stand.
 Keywords: Increment, Light Intensity, Planting Line Direction

Impact of Mg ii interstellar medium absorption on near-ultraviolet exoplanet transit measurements

ABSTRACT Ultraviolet (UV) transmission spectroscopy probes atmospheric escape, which has a significant impact on planetary atmospheric evolution. If unaccounted for, interstellar medium absorption (ISM) at the position of specific UV lines might bias transit depth measurements, and thus potentially affect the (non-)detection of features in transmission spectra. Ultimately, this is connected to the so called ‘resolution-linked bias’ effect. We present a parametric study quantifying the impact of unresolved or unconsidered ISM absorption in transit depth measurements at the position of the Mg ii h&k resonance lines (i.e. 2802.705 Å and 2795.528 Å, respectively) in the near-ultraviolet spectral range. We consider main-sequence stars of different spectral types and vary the shape and amount of chromospheric emission, ISM absorption, and planetary absorption, as well as their relative velocities. We also evaluate the role played by integration bin and spectral resolution. We present an open-source tool enabling one to quantify the impact of unresolved or unconsidered Mg ii ISM absorption in transit depth measurements. We further apply this tool to a few already or soon to be observed systems. On average, we find that ignoring ISM absorption leads to biases in the Mg ii transit depth measurements comparable to the uncertainties obtained from the observations published to date. However, considering the bias induced by ISM absorption might become necessary when analysing observations obtained with the next generation space telescopes with UV coverage (e.g. LUVOIR, HABEX), which will provide transmission spectra with significantly smaller uncertainties compared to what obtained with current facilities (e.g. HST).

Effect of electric field induced structural ordering on photo-luminescence and piezoelectric response of praseodymium doped (Na0.41K0.09Bi0.5)TiO3 ceramics

A correlation of the ferroelectric and photoluminescence response to the structural ordering of praseodymium doped (Na0.41K0.09Bi0.5)TiO3 has been investigated. It has been observed that the ferroelectric and photoluminescence response lacks one-to-one correlation. The ferroelectric response is generally driven by long-range polar ordering. On the contrary, photoluminescence response is concomitant to the local site symmetry around the praseodymium ion. The optimum ferroelectric response has been observed for 1.0 at. % praseodymium doped (Na0.41K0.09Bi0.5)TiO3, whereas for the sample with higher doping concentration, it diminishes gradually due to disruption of the long-range ordering. On the other hand, with the establishment of long-range ordering, no noticeable shift in the position and shape of the photoluminescence lines has been observed. However, a quenching in the photoluminescence intensity of the hypersensitive transitions (1D2 → 3H4) takes place, which has been associated with the modification in the local site symmetry. It has been argued that structural modification has an influence on the photoluminescence intensity but does not affect the energy levels of these transitions. The observed dielectric, piezoelectric, and photoluminescence response has been explained on the basis of the amphoteric nature of praseodymium in (Na0.41K0.09Bi0.5)TiO3.

High sensitivity absorption spectroscopy of hydrogen chloride near 770nm

The Cavity Ring-Down Spectra (CRDS) of hydrogen chloride were recorded in the 12,943–13,295 cm−1 region with sensitivity of 4 × 10−11 cm−1. The lines P(4) – P(12) of the 5–0 band of two H35Cl and H37Cl isotopologues were assigned in these spectra. The positions, intensities, self-broadening and self-pressure-induced shift coefficients of these lines were measured. The measured line positions are in a good agreement with those presented in the HITRAN2020 database. The measured line intensities are 1.3 times greater than those from the HITRAN2020 database. The measured self-broadening coefficients are in a good agreement with the HITRAN2020 values for the small angular momentum quantum numbers and slightly exceed the HITRAN2020 values for the large angular momentum quantum numbers.

Inclusion of Bidirectional Angular Positioning Deviations in the Kinematic Model of a Six-DOF Articulated Robot for Static Volumetric Error Compensation

To improve a robot’s absolute positioning accuracy, researchers have extensively studied the robot kinematic model containing position and orientation errors of rotary axis average lines, widely known as Denavit–Hartenberg (D-H) parameters. To further improve the absolute positioning accuracy of industrial robots, this article proposes a novel kinematic model and its identification scheme. The proposed kinematic model for a serial-linked industrial robot contains the bidirectional angular positioning deviations of each rotary axis, represented in a lookup table, in addition to its D-H parameters. The angular positioning deviations of the rotary axes are modeled as a function of angular command positions, along with the direction of rotation to model the influence of backlash. This article also proposes a novel approach to identify the proposed kinematic model with the bidirectional angular positioning deviations using a laser tracker with indexing each rotary axis at specified angular positions (“circle point method”). Moreover, the model-based compensation technique is being experimentally investigated to validate the prediction accuracy of the proposed model. The findings of the experiment show that the proposed model enhances the robot’s absolute positioning accuracy significantly over the entire workspace.

Facial Skin Texture and Distributed Dynamic Kernel Support Vector Machine (DDKSVM) Classifier for Age Estimation in Facial Wrinkles

Facial wrinkles are common aspects of ageing human skin that may be used in a variety of image-based ageing applications. Wrinkles on the face are 3D skin characteristics that appear as tiny discontinuities or fissures, as well as inconsistencies in the surrounding skin texture. Existing image-based techniques to ageing skin analysis focus on wrinkles as texture rather than curvilinear discontinuity/crack or irregularity characteristics. Picture processing methods are useful for reconstructing and manipulating an image in order to produce various images. The goal of this study is to create a FWDAE-IP (Face Wrinkles Detection and Age Estimate with Image Processing) system that can identify the exact position of wrinkle lines in relation to cracks/ discontinuities, abnormalities, and age estimation using skin texture data from one face image. This FWDAE-IP system is performed based on four major steps: Preprocessing, Skin texture feature extraction, wrinkles detection, and age estimations. In the first step, preprocessing is performed by rotation angle. In the second step, GFs (Gabor Filters), ALTPs (Adaptive Local Ternary Patterns), and AAMs (Active Appearance Models) are introduced against variation in pose or illumination. In the third step, GMM-EM (Gaussian Mixture Model- Expectation-Maximization) is introduced for detecting irregularities in the wrinkles, Gabor filters and image morphology is introduced for detecting discontinuity/crack in the wrinkles. In the fourth step, age estimation is performed based on the detected with wrinkles by DDKSVM (Distributed Dynamic Kernel Support Vector Machine) classifier. The results of age estimation methods are measured via the evaluation metrics such as MAEs (Mean Absolute Error), CSs (Cumulative Scores), accuracy, SSIMs (structural Similarity Indices), and JSIs (Jcard Similarity Indices). The experimentation work is performed based on FG-NET database.

Vertical displacement monitoring using the modified leveling method

The article aims to present and verify the effectiveness of a quick (modified) approach to measuring vertical displacements and then to measure with this method and calculate the values of vertical displacements assumed on real objects of the controlled points network. As an example of the possibility of using the proposed method, data obtained from the geodetic monitoring of the control and measurement networks established on the ground structural elements of the Bydgoszcz University of Science and Technology were used. The presented approach eliminates the influence of the error in the position of the sight line of the device, reduces the number of measuring stations, and gives the possibility of a more favorable selection of measuring stations. The verified approach significantly shortens the time of measurements (by about 37%) and reduces the work-made cost. Furthermore, the numerical analysis showed the proposed solution's effectiveness without reducing the accuracy of obtained results.

An Integrated Method for River Water Level Recognition from Surveillance Images Using Convolution Neural Networks

Water conservancy personnel usually need to know the water level by water gauge images in real-time and with an expected accuracy. However, accurately recognizing the water level from water gauge images is still a complex problem. This article proposes a composite method applied in the Wuyuan City, Jiangxi Province, in China. This method can detect water gauge areas and number areas from complex and changeable scenes, accurately detect the water level line from various water gauges, and finally, obtain the accurate water level value. Firstly, FCOS is improved by fusing a contextual adjustment module to meet the requirements of edge computing and ensure considerable detection accuracy. Secondly, to deal with scenes with indistinct water level features, we also apply the contextual adjustment module for Deeplabv3+ to segment the water gauge area above the water surface. Then, the area can be used to obtain the position of the water level line. Finally, the results of the previous two steps are combined to calculate the water level value. Detailed experiments prove that this method solves the problem of water level recognition in complex hydrological scenes. Furthermore, the recognition error of the water level by this method is less than 1 cm, proving it is capable of being applied in real river scenes.

Snow Cover and Snowline Variation in Relation to Land Surface Temperature in Spiti Valley, Himachal Pradesh, India

Spiti Valley, a cold desert mountain is located in the Trans Himalaya region where snow cover is a dominant type of land cover. Characterized, as a rain shadow area where precipitation occurs in the form of snowfall and almost negligible rainfall. Thus, snowmelt water is a single source of freshwater which is used in agricultural and household activities by mountain dwellers. The main objective of the study is to determine the effects of Land Surface Temperature (LST) on snow cover and snow line position in Spiti Valley. This study is based on geospatial techniques in which Landsat imagery was the main source of data for snow cover, snow line position, and Land Surface Temperature (LST) analysis. It includes Operational Land Imager/Thermal Infrared Sensor (OLI / TIRS) and Thematic Mapper (TM) scenes of the twelve months for the reference years 1990 and 2015. Snow cover was extracted from January to December; using Normalised Difference Snow Index (NDSI). According to NDSI result, the average snow cover was 4, 68,998.50 ha (61.68%) in 1990 and 3, 69,676.4 ha (48.71%) in 2015. Approximately 98,422.08 ha (0.51%) of snow cover was converted into a non-snow cover area at an average rate of 3,937 ha/year. Analysis of the position of the snow line indicates that it moved upward 445.11 meters in Spiti Valley during the study period. In 1990, the snow line was visible at the height of 5,159.37 meters at the end of the summer, but reached at 5,604.48 meters height in 2015, marking the loss of snow accumulation in the lower heights.

VECTOR MAGNETOMETRY USING A SINGLE NV–13C COMPLEX IN DIAMOND

A method of vector magnetometry, implemented using a single NV–13C spin system in a diamond, is proposed. The method is based on a priori knowledge of the hyperfine interaction characteristics and on the presence of experimentally measured line positions in the optically detectable magnetic resonance spectrum of such a system. The method was experimentally tested on the NV–13C system, in which the 13С atom is located in the third coordination sphere of the NV center.

Preliminary assessment of the mooring fatigue performance of a semi-submersible platform in time-domain utilizing fracture mechanics-based approach

• Fully coupled dynamic analysis of platform-mooring system is performed in time-domain. • A self-integrated program is developed for mooring fatigue analysis through fracture mechanics-based approach. • Mooring fatigue performance of a submerged platform is studied through the remaining fatigue life at different positions of diverse lines. • The influence of corrosion on fatigue performance is investigated through a finite element model with gradual degradation. This paper aims to propose a universal time-domain fatigue evaluation method for mooring fatigue analysis of marine structures utilizing a fracture mechanics-based approach. First, the tension history of the mooring lines is calculated in the time-domain through hydrodynamic analysis and converted into mooring tension cycles with corresponding ranges via the rain-flow counting method. Subsequently, mooring fatigue performance is characterized through a self-integrated program which can realize the automatic crack propagation, Stress Intensify Factor (SIF) calculation and fatigue life prediction. Finally, a comparative study is implemented to further investigate the fatigue performance at different evaluation positions of various mooring lines under various corrosion rates. Results illustrate that fatigue life is relatively longer for mooring lines on the wave-ward side and greater at both ends of each line for the applied semi-taut mooring system. Most residual mooring fatigue life is more than 129 years with an initial surface crack of a = 0.5 mm, and the crack growth rate accelerates dramatically when reaching about 2.1% of the chain diameter. Remaining fatigue life decreases significantly under increasing corrosion rates, which is typically reduced by 39.4%, 48%, 47.8% and 38.6% for mooring lines 2, 5, 8, and 11 at 0.2 mm/year corrosion rate.

On using ab initio calibration to fit temperature from AlO B-X emission

Aluminum Oxide (AlO) emission can be an important indicator of reaction and temperature in combustion and explosion systems. The Δv=-1 and particularly Δv=-2 sequences are attractive for temperature measurement, but have presented some challenges in modelling, especially for high vibrational energy transitions. Recent studies and ab initio simulations have offered parameters for the simulation of high resolution AlO spectra (Patrascu et.al. Mon. Not. R. Astron. Soc., 2015). In this paper we compare simulated spectra with high resolution emissions of AlO, both from laser induced breakdown spectroscopy and carefully calibrated shock tube experiments (3000<T<5000 K). In this manner, we assess the spectral model and its capacity for temperature assignment, rather than assume model accuracy and a best-fit-temperature. The experimental and modeled spectra agree below 0.1 Å resolution, and line features agree within our experimental resolution, in some regions down to 3 pm. Least squares fitting was performed on the experimental spectra, resulting in temperatures in agreement with calibration temperatures. The Δv=-2 sequence fits with residuals less than 4%. Our analysis suggests that experimental measurements with a resolution of 0.2 nm in this sequence can reliably fit the temperature within 100 K. Because of the apparently accurate fits to temperature, apparent accuracy of line position list, and reasonableness of line width model, we assess that the line strengths are likely also accurate and that ab initio simulated calibrations are useful for measuring temperature in AlO.

The NOSL-296 high resolution 14N216O line list for atmospheric applications

The Nitrous Oxide Spectroscopic Line list (NOSL-296) presented in this work is an empirical line list for the main isotopologue of nitrous oxide, 14N216O, mainly dedicated to atmospheric applications. It contains line positions and intensities at a reference temperature of 296 K calculated using the effective operator approach. The intensity cutoff is 10−30 cm/molecule. Almost 900,000 lines covering the 0.02–13,378 cm−1 spectral range are included in NOSL-296. The line list is based on the fitted non-polyad models of the effective Hamiltonian and effective dipole moment operator describing globally an exhaustive review of experimental data collected from the literature (more than 51,500 line intensities). The non-polyad model of effective Hamiltonian has been elaborated in [Tashkun SA, J Quant Spectrosc Radiat Transfer 2019;231:88–101, doi:10.1016/j.jqsrt.2019.04.023] while the non-polyad model of the effective dipole moment operator is developed in the present work. The fitted models are able to reproduce measured positions and intensities with accuracies compatible with measurement uncertainties. Comparison of NOSL-296 with HITRAN2020 and Ames-296 line lists are discussed. The NOSL-296 line list is provided as a Supplementary Material and freely accessible at https://ftp.iao.ru/pub/LTS/NOSL-296/.

The rotational spectrum of HD broadened by H2 at temperatures between 100 – 296 K

Laboratory measurements of the R(0) – R(3) pure rotational transitions of hydrogen deuteride (HD) have been performed at low pressures (< 1 bar) and temperatures between 98 and 296 K. The measurements were conducted using a Fourier transform spectrometer coupled to the Soleil synchrotron far-infrared source to obtain pure HD and HD-H2 mixture spectra. The observed spectra have been fitted using a non-linear least-squares multispectral fitting program. For each transition the line position, intensity, pressure broadening, pressure-induced frequency shift, and the temperature dependencies of these quantities have been determined simultaneously. These spectroscopic line parameters are compared to previous measurements made at higher gas pressures. Notably the present, and previous, measurements of the self- and H2-broadened linewidths are smaller by a factor of five compared with those listed in the HITRAN and GEISA databases. This work is applicable to the low pressure, low temperature regimes found in the atmospheres of the giant gaseous planets.