Range Of Distances Research Articles

Application of compressive sensing to equivalent source method on near-field acoustic holography

Near-field acoustic holography (NAH) is an acoustic visualization technique that uses a microphone array to measure the radiated sound waves from a source in the near-field. In the present study, the equivalent source method (ESM) and the 2D spatial Fourier transform based on the generalized discrete Fourier series (GDFS) are compared, and the reconstruction performance of NAH using compressed sensing (CS) combined with both theories for NAH measurements is discussed. Additionally, the influence of different array designs (regular and pseudo-random) on the reconstruction performance of NAH is investigated. Simulations and experimentation are used to demonstrate its feasibility. In the simulation, three source models (dipole, longitudinal quadrupole and simply supported rectangular plate) are tested over a range of frequencies, SNR and reconstruction distances. The consequence indicates that use of GDFS results in a large reconstruction error in all test conditions under the rectangular array, especially in the high frequency range. The combination of a pseudo-random array and ESM-L1 provides the best reconstruction performance in most test conditions. In the experiment, two sets of pseudo-random microphone arrays with different diameters were used. They were tested separately for the dual loudspeakers and vibrating plate. ESM-L1 is suitable for reconstructing sound fields with sparse source distributions, whereas ESM-L2 is suitable for reconstructing sound fields with continuous source distributions, such as the radiated acoustic field of a vibrating plate. However, the use of pseudo-random arrays in combination with ESM is indeed a better solution for NAH.

The Optimization of Pair Distribution Functions for the Evaluation of the Degree of Disorder and Physical Stability in Amorphous Solids.

The amorphous form of poorly soluble drugs is physically unstable and prone to crystallization, resulting in decreased solubility and bioavailability. However, the conventional accelerated stability test for amorphous drugs is time-consuming and inaccurate. Therefore, there is an urgent need to develop rapid and accurate stability assessment technology. This study used the antitumor drug nilotinib free base as a model drug. The degree of disorder and physical stability in the amorphous form was assessed by applying the pair distribution function (PDF) and principal component analysis (PCA) methods based on powder X-ray diffraction (PXRD) data. Specifically, the assessment conditions, such as the PDF interatomic distance range, PXRD detector type, and PXRD diffraction angle range were also optimized. The results showed that more reliable PCA data could be obtained when the PDF interatomic distance range was 0-15 Å. When the PXRD detector was a semiconductor-type detector, the PDF data obtained were more accurate than other detectors. When the PXRD diffraction angle range was 5-40°, the intermolecular arrangement of the amorphous drugs could be accurately predicted. Finally, the accelerated stability test also showed that under the above-optimized conditions, this method could accurately and rapidly assess the degree of disorder and physical stability in the amorphous form of drugs, which has obvious advantages compared with the accelerated stability test.

An Intruder-Free Fock Space Coupled-Cluster Study of the Potential Energy Curves of LiMg+ within the (2,0) Sector.

The potential energy curves (PECs) and spectroscopic constants of the ground and excited states of a LiMg+ molecular cation were investigated. We obtained accurate results for the fifteen lowest-lying states of the LiMg+ cation using the Intermediate Hamiltonian Fock Space Multireference Coupled Cluster (IH-FS-CC) method applied to the (2,0) sector. Relativistic corrections were accounted for using the third-order Douglas-Kroll method. In each instance, smooth PECs were successfully computed across the entire range of interatomic distances from equilibrium to the dissociation limit. The results are in good accordance with previous studies of this molecular cation. Notably, this study marks the first application of IH-FS-CC in investigating a mixed alkali and alkaline earth molecular cation, proving its usability in determining accurate PECs of such diatomics and their spectroscopic constants.

A Mach–Zehnder Fabry–Perot Hybrid Fibre-Optic Interferometer for a Large Measurement Range Based on the Kalman Filter

To solve the short working distance and small measurement range of an all-fibre interferometer, we proposed a Mach–Zehnder Fabry–Perot hybrid fibre-optic interferometry system based on sinusoidal phase modulation. In this paper, a low-finesse fibre interferometer with a larger linear operating range for displacement measurement is realised using a self-collimating probe and incorporating a Kalman filter-based phase demodulation algorithm. Through experimental comparisons, it is demonstrated that the interferometer proposed in this paper can effectively reduce the phase delay, compensate for the depth of modulation drift, and correct the error due to parasitic interference introduced by the optical path structure through the algorithm. A linear large measurement working range of 20 cm is realised.

Non-coaxial optical screen based projection 3D display with extended viewing distance range

A non-coaxial optical screen based projection 3D display with extended viewing distance range is proposed. The proposed 3D display is composed of a projector array and a non-coaxial optical screen constructed with a series of one-dimensional retro-reflective components (1DRRCs). The projector array projects parallax images onto the screen, then the non-coaxial optical screen converges light to linearly shaped region which pass through the position of the projector and forms a view area by one-dimensional retro-reflection. At each view area, different parallax images corresponding to the projectors can be observed respectively, therefore 3D display is formed. In the proposed 3D display, the optical axis of each 1DRRC shares a common direction and isn't parallel to the normal of the non-coaxial optical screen plane. Consequently, reflected light converges into a linearly shaped region. This linearly shaped region isn't parallel to the non-coaxial optical screen, so that it can cover a extended range from back to front and lead to larger viewing distance range. A prototype is developed to verify the principle. In the prototype, the viewing distance range covers a range of 959–2083 mm, then demonstrating the proposed 3D display agree well with the theory.

Effects of a Modified Long-Acting Cocktail on Analgesia and Enhanced Recovery After Total Hip Arthroplasty: A Double-Blinded Randomized Clinical Trial

BackgroundWe compared the efficacy and safety of a modified cocktail for postoperative analgesia and early functional rehabilitation in patients undergoing total hip arthroplasty (THA). MethodsMagnesium sulfate and sodium bicarbonate were added to a cocktail of ropivacaine, epinephrine, and dexamethasone. Primary outcome measures were visual analog scale (VAS) pain scores at various intervals after surgery, morphine consumption for rescue analgesia after surgery, and time to first rescue analgesia. Secondary outcomes were hip function after surgery, daily walking distance, quadriceps muscle strength, and the incidence of postoperative adverse reactions. ResultsMorphine consumption was significantly lower in the modified cocktail group than in the control group in the first 24 hours after surgery (6.2 ± 6.0 versus 14.2 ± 6.4 mg, P < .001), as was total morphine consumption (10.0 ± 8.6 versus 19.2 ± 10.1 mg, P < .001). The duration of the first rescue analgesia was significantly prolonged (23.7 ± 10.3 versus 11.9 ± 5.8 mg, P < .001). Morphine consumption was also reduced in the magnesium sulfate and sodium bicarbonate groups over a 24-hour period compared to the control group (P < .001). The modified cocktail group had significantly lower resting VAS pain scores than the control group within 24 hours after surgery (P < .050). The VAS pain scores during movement within 12 hours after surgery were also lower (P < .050). The experimental groups showed better hip range of motion (P < .050) and longer walking distance (P < .050) on the first postoperative day, and levels of inflammatory markers were significantly reduced. The incidence of postoperative adverse reactions was similar among the 4 groups. ConclusionsThe modified cocktail with a new adjuvant can prolong the duration of postoperative analgesia, reduce the dosage of rescue analgesics, and accelerate early postoperative functional recovery in patients undergoing THA.

Rainfall Differences and Possible Causes of Similar-Track Tropical Cyclones Affected and Unaffected by Binary Tropical Cyclones (BTCs) in China

Binary tropical cyclones (BTCs) typically refer to the coexistence of two tropical cyclones (TCs) within a specific distance range, often resulting in disastrous rainstorms in coastal areas of China. However, the differences in rainfall and underlying causes between BTC-influenced typhoons and general typhoons remain unclear. In this article, the TC closer to the rainfall center in the BTC is referred to as the target typhoon (tTC), while the other is termed the accompanying typhoon (cmp_TC). This study compares and analyzes the rainfall differences and potential causes of tTCs and similar typhoons (sim_TC) with a comparable track but which are unaffected by BTCs from 1981 to 2020. The results show that: (1) On average, tTCs and cmp_TCs experience 18.79% heavier maximum daily rainfall compared to general TCs, with a significantly increased likelihood of rainfall ≥250 mm. (2) Given similar tracks, the average rainfall for tTCs (212.62 mm) is 30.2% heavier than that for sim_TCs (163.30 mm). (3) The analysis of potential impact factors on rainfall (translation speed, intensity, direction change) reveals that sim_TCs move at an average of 21.38 km/h, which is about 19.66% faster than the 17.87 km/h of tTCs, potentially accounting for the observed differences in rainfall. (4) Further investigation into the causes of west–east oriented BTC rainfall in the Northern Fujian (N_Fujian) region suggests that water vapor transport and slowing down of the translation speed are the possible mechanisms of BTC influence. Specifically, 80% of tTCs receive water vapor from the direction of their cmp_TC, and the steering flow for tTC is only 59.88% of that for sim_TC.

Hirundo rustica (Barn Swallows) and Tachycineta bicolor (Tree Swallows) select wetlands in agriculturally intensive landscapes, as revealed by GPS tracking

Abstract Aerial insectivorous birds breeding in North America have experienced decades of population declines for reasons hypothesized to be related to changes in their insect prey. In agricultural landscapes, land management practices can affect insect communities, leading to concerns that ongoing trends toward more intensive cultivation could affect the ability of farmland-breeding aerial insectivores to forage and provision their offspring with aerial insect prey. To understand how differences in agricultural intensity may affect the foraging behavior of different aerial insectivore species, we used GPS tags to compare the movements and habitat use of 2 species with different foraging ecologies, Hirundo rustica (Barn Swallow) and Tachycineta bicolor (Tree Swallow), breeding at 17 sites in agricultural landscapes in Saskatchewan, Canada. Although we identified differences in foraging behavior consistent with each species’ reported ecological traits, including T. bicolor foraging farther and over larger areas than H. rustica, overall foraging behavior was similar between species. Resource selection function analyses indicated that both species used wetlands disproportionately often relative to local wetland availability, especially when detected farther from their nests. Hirundo rustica and T. bicolor both also avoided cropped foraging habitat, using it proportionally less than it was locally available. In landscapes with greater wetland cover, both species selected for wetland habitat more strongly, and among T. bicolor, higher wetland density decreased maximum foraging distance and home range area. In contrast, we found no effect of crop cover on foraging habitat selection or foraging movements. These findings suggest that H. rustica and T. bicolor breeding in Saskatchewan agroecosystems share similar foraging strategies, with wetland habitats appearing to be highly important despite comprising only a small proportion of landscape area. Overall, these results indicate that protecting wetland habitats should be a priority for aerial insectivore conservation in the intensive agricultural landscapes such as the Canadian prairies.

Identification of two novel subtypes of hepatitis C virus genotype 8 and a potential new genotype successfully treated with direct acting antivirals.

Hepatitis C virus (HCV) has a high genetic diversity and is classified into 8 genotypes and over 90 subtypes with some endemic to specific world regions. This could compromise direct-acting antiviral (DAA) efficacy and global HCV elimination. We characterised HCV subtypes 'rare' to the UK (non-1a/1b/2b/3a/4d) by whole genome sequencing via a national surveillance programme. Genetic analyses to determine the genotype of samples with unresolved genotypes were undertaken by comparison with ICTV HCV reference sequences. Two HCV variants were characterised as being closely related to the recently identified genotype 8 (GT8), with >85% pairwise genetic distance similarity to GT8 sequences and within the typical inter-subtype genetic distance range. The individuals infected by the variants were UK residents originally from Pakistan and India. In contrast, a third variant was only confidently identified to be more similar to GT6 compared to other genotypes across 6% of the genome and was isolated from a UK resident originally from Guyana. All three were cured with pangenotypic DAAs (Sofosbuvir + Velpatasvir or Glecaprevir + Pibrentasvir) despite the presence of resistance polymorphisms in NS3 (80 K/168E), NS5A (28 V/30S/62L/92S/93S) and NS5B (159F). This study expands our knowledge of HCV diversity by identifying two new GT8 subtypes and potentially a new genotype.

Silver(I) Octanuclear Complexes Containing N'-(4-Oxotiazolidin-2-Iliden)picolinohydrazonamide and Nitrate as Bridge Ligands. An Example of Solvatomorphism?

The versatile coordination chemistry of (2Z,N'E)-N'-(4-oxothiazolidin-2-ylidene)picolinohydrazonamide (HAmDHotaz) facilitated the synthesis of new complexes with different silver(I) salts. This paper describes the synthesis and characterization, through elemental analysis and spectroscopic techniques (when solubility permits), of a series of compounds that illustrate the coordinative and structural diversity achievable with the HAmDHotaz ligand. Five silver clusters containing the [Ag8(AmDHotaz)4]4+ nucleus were structurally analyzed by single-crystal X-ray diffraction and were found to exhibit solvomorphism. The compositions of these are [Ag8(AmDHotaz)4(NO3)3(MeOH)(H2O)](NO3)·MeOH·7.5H2O (1), {[Ag8(AmDHotaz)4(NO3)3(H2O)2](NO3)·9.5(H2O)}n (2), {[Ag8(AmDHotaz)4(NO3)3(H2O)2](NO3)·11.5(H2O)}n (2a), {[Ag8(AmDHotaz)4(NO3)2(H2O)2](NO3)(OH)·6H2O}n (3), and {[Ag8(AmDHotaz)4(NO3)2(H2O)](NO3)(OH)·4.5H2O}n (3a). Argentophilic interactions are present in each of the octanuclear structures, where Ag···Ag distances range from 2.828(2) to 2.986(1) Å. These distances are influenced by crystal packing, determined by the counterion and solvent molecules in the structure. In the solvatomorphs, solvent molecules were observed to be disordered. Various hydrogen-bonding interactions, such as N-H···O-N, O-H···O, N-H···O═C, C-H···O-N, and π-π stacking interactions, contribute to the crystal packing. The influence of these weak interactions on the crystal packing was further analyzed using DFT calculations and Bader's theory of atoms-in-molecules, with a focus on argentophilic interactions and Ag···S interactions.

Spectral decomposition of ground motions in New Zealand using the generalized inversion technique

SUMMARY To gain new insights into ground-motion phenomena in New Zealand (NZ), we apply the non-parametric generalized inversion technique (GIT) in the Fourier domain to isolate the systematic source, path, and site effects from 20 813 seismograms, recorded by 693 sensors at 439 unique locations, from 1200 shallow crustal events (Mw &amp;gt; 3) during the period 2000–2021. From the inverted source spectra, we derive Brune's stress parameter, ∆σ, which is found to follow a lognormal distribution with a log10 standard deviation of 0.36 or equivalently 0.83 in natural log unit. ∆σ slightly increases with focal depth and is practically independent of earthquake size (i.e. self-similar), but displays a statistically significant spatial clustering. Based on the inverted attenuation, a trilinear geometric-spreading function, and a distance-dependent quality-factor Q(f) model are found to well describe the attenuation in NZ; though a single $Q( f )$ model is also obtained for the whole distance range: $Q( f ) = 149.1{f}^{0.62}$. Using the site response decomposed from GIT, we find that the soil classification scheme specified in NZ seismic code, NZS1170.5, has a limited capability in discerning the site-specific frequency-dependent amplification functions in comparison to a non-parametric clustering with the same number of discrete classes. The potential use of the spatial variation in source parameters from this GIT analysis in region-specific physics-based simulations is discussed.

Efficacy of adding infiltration between the popliteal artery and the capsule of the posterior knee (IPACK) to adductor canal block and local infiltration analgesia in total knee arthroplasty: A retrospective cohort study.

Local infiltration analgesia (LIA), adductor canal block (ACB), and infiltration between the popliteal artery and the capsule of the posterior knee (IPACK) are popular multimodal analgesia techniques used during total knee arthroplasty (TKA). This study aimed to explore the efficacy of adding the IPACK technique to ACB and LIA in patients undergoing TKA. In this retrospective cohort study, patients who underwent primary unilateral TKA were divided into two groups based on their date of admission. Sixty-three patients underwent IPACK, ACB and LIA (IPACK group) during surgery, while 60 patients underwent ACB and LIA (control group). The primary outcome was the postoperative administration of morphine hydrochloride as a rescue analgesic. Secondary outcomes included time to first rescue analgesia, postoperative pain assessed using the visual analog scale (VAS), functional recovery assessed by knee range of motion and ambulation distance, time until hospital discharge, and complication rates. The two groups were similar in average postoperative 0-to-24-h morphine consumption (11.8mg for the control group vs 12.7mg for the IPACK group, p = .428) and average total morphine consumption (18.2mg vs 18.0mg, p = .983) during hospitalization. There were also no significant differences in the secondary outcomes. The addition of IPACK to ACB and LIA did not provide any clinical analgesic benefits. Orthopedic surgeons and anesthesiologists are justified in using ACB and LIA without IPACK for TKA.

Simulation Study of Crack Extension in Concrete Blast Walls Under Blast Impacts

To study the crack propagation law of concrete blast wall (CBW) under explosion impact, this paper uses ANSYS/LS-DYNA finite element software to numerically simulate the crack growth law under the influence of different explosion loads and explosion distances. The results show that: after the explosion, the change of composite velocity of each measuring point on the wall at a certain distance from the explosion point is mainly divided into three stages: explosive initiation stage, the composite velocity and acceleration of each measuring point are zero; In the accelerated crack growth stage, the acceleration of each measuring point reaches the peak value; At the stage of uniform crack growth, the crack will no longer accelerate its diffusion. When the explosion distance is fixed, the explosion load is positively correlated with the number of radial cracks; When the explosion load is small, there are only inconspicuous circumferential cracks in the center of the wall. When TNT equivalent is 15g, 25g, and 30g, CBW circumferential cracks increase and mainly concentrate in the center, and gradually expand outward to the boundary in the form of concentric circles. At the same time, when the explosion load is constant, the explosion distance is negatively related to the number of cracks, mainly radial cracks, while circumferential cracks are always distributed in the center of the wall. In the range of simulated explosion distance, the cracks only appear at the boundary and gradually change from square to round with the increase of explosion distance, and the crack area decreases. The research results can provide a theoretical basis for avoiding such accidents and a powerful reference for accident investigators to determine the location and intensity of explosion sources.

Revisiting the rovibrational (de-)excitation of molecular hydrogen by helium

Context. The collisional (de-)excitation of H2 by He plays an important role in the thermal balance and chemistry of various astro-physical environments, making accurate rate coefficients essential for interpreting observations of the interstellar medium. Aims. Our goal is to utilize a state-of-the-art potential energy surface (PES) to provide comprehensive state-to-state rate coefficients for He-induced transitions among rovibrational levels of H2. Methods. We performed quantum scattering calculations for the H2-He system. Thus, we were able to provide state-to-state rate coefficients for 1059 transitions between rovibrational levels of H2, with internal energies up to ≃15 000 cm−1, for temperatures ranging from 20 to 8000 K. Results. Our results demonstrate a good agreement with previous calculations for pure rotational transitions between low-lying rotational levels. However, we do find significant discrepancies for rovibrational processes involving highly-excited rotational and vibrational states. We attribute these differences to two key factors: (1) the broader range of intramolecular distances covered by ab initio points and (2) the superior accuracy of the PES, resulting from the utilization of the state-of-the-art quantum chemistry methods, compared to previous lower-level calculations. Conclusions. Radiative transfer calculations performed with the new collisional data indicate that the population of rotational levels in excited vibrational states experiences significant modifications, highlighting the critical need for this updated dataset in models of high-temperature astrophysical environments.

Influencing mechanism of nanoscale He bubbles on the crack propagation in TiT1.75 under tension

This work investigates the influence of the pre-existing He bubble on the crack propagation in TiT1.75 with molecular dynamic simulations. Under high strain rate tension, TiT1.75 exhibits typical brittle fracture characteristics with low fracture toughness at the microscopic scale, and the crack propagation path approximately follows the (111) plane with normal stretching direction. However, the presence of He bubble may change the stress concentration near the crack tip, resulting in the bending and even branching of cracks. The position relationship between He bubbles and crack tips is discussed, and the variation of the tensile strength with the distance and the angle is revealed. The total length and pattern of crack propagation are also presented. It is found that the tensile strength approximately linearly decreases with the He bubble concentrations, and the self-expansion and coalescence of He bubbles will gradually dominate the fracture process.

Numerical Simulation of Tailings Mortar Flowing from Dam Break by Variable Concentration Two-phase Flow Algorithm

A dam break accident of tailings pond may result in serious loss of the residents' lives and property, and usually leads to surrounding environmental disaster. Accurately calculating the flowing distance and inundation range of discharged tailings is important but remains to be solved. The main feature of tailings mortar movement is that solid particles continue to sink and accumulate during the flow process, which makes the solid concentration in the mortar constantly change, thus altering the rheological properties of the mortar. Therefore, the advancement of tailings mortar is a kind of two-phase unsteady flow with variable solid-phase concentration. In conventional numerical calculations of tailings flow, the rheological parameters of the Bingham model used are given fixed values with no consideration of concentration change, resulting in inaccurate calculation results and difficulty reflecting the phenomenon of tailings sands accumulation along the way. In this paper, a variable concentration two-phase flow model is proposed and then applied to a typical tailings dam failure case. The flow features and inundation range of the tailings mortar are analyzed and are found to be basically consistent with the field investigation, which means the proposed two-phase flow algorithm is reasonable and reliable.

Evolution of coronal mass ejections with and without sheaths from the inner to the outer heliosphere: Statistical investigation for 1975 to 2022

Aims. This study covers a thorough statistical investigation of the evolution of interplanetary coronal mass ejections (ICMEs) with and without sheaths through a broad heliocentric distance and temporal range. The analysis treats the sheath and magnetic obstacle (MO) separately in order to gain more insight on their physical properties. In detail, we aim to unravel different characteristics of these structures occurring over the inner and outer heliosphere. Methods. The method is based on a large statistical sample of ICMEs probed over different distances in the heliosphere. For this, information about detection times for the sheath and MO from 13 individual ICME catalogs was collected and crosschecked. The time information was then combined into a main catalog that was used as the basis for the statistical investigation. The data analysis based on this catalog covers a large number of spacecraft missions, enabling in situ solar wind measurements from 1975 to 2022. This allowed us to study the differences between solar cycles. Results. All the structures under study (sheath, MO with and without sheath) show the biggest increase in size together with the largest decrease in density at a distance of ∼0.75 AU. At 1 AU, we found different sizes for MOs with and without a sheath, with the former being larger. Up to 1 AU, the upstream solar wind shows the strongest pileup close to the interface with the sheath. For larger distances, the pileup region seems to shift, and it recedes from that interface further into the upstream solar wind. This might refer to a change in the sheath formation mechanism (driven versus non-driven) with heliocentric distance, suggesting the relevance of the CME propagation and the expansion behavior in the outer heliosphere. A comparison to previous studies showed inconsistencies over the solar cycle, which makes more detailed studies necessary in order to fully understand the evolution of ICME structures.

A time-fuel hybrid optimal guidance for micro/nano satellite’s glideslope approach

Aimed at the trajectory planning problem of micro/nano satellites’ approaching missions under multiple constraints, this paper proposes a V-bar glideslope maneuver optimization method considering both time and fuel consumption. A dual-objective trajectory optimization model is established based on the CW motion equation, considering the constraints of trajectory and impulse. The optimal solution set of the glideslope point position and maneuvering time is obtained by employing the NSGA2 algorithm. In order to reduce computational complexity, a method for simplifying trajectory optimization is proposed. By solving a constrained dual-impulse optimization problem, the feasible range of distance and transfer time between adjacent glideslope points are obtained, which transforms the constraint equations of the glideslope maneuver optimization into the search space of optimization variables. The problem is simplified to an unconstrained optimization problem. Finally, a simulation is conducted with the approaching mission of a typical micro/nano satellite. The results demonstrate that the proposed method can provide an optimal solution set considering both fuel and time consumption, offering a flexible maneuver planning strategy for on-orbit application.

The Next Generation Virgo Cluster Survey. XXXVII. Distant RR Lyrae Stars and the Milky Way Stellar Halo Out to 300 kpc

RR Lyrae stars are standard candles with characteristic photometric variability and serve as powerful tracers of Galactic structure, substructure, accretion history, and dark matter content. Here we report the discovery of distant RR Lyrae stars, including some of the most distant stars known in the Milky Way halo, with Galactocentric distances of ∼300 kpc. We use time-series u*g′i′z′ Canada–France–Hawaii Telescope/MegaCam photometry from the Next Generation Virgo Cluster Survey (NGVS). We use a template light-curve fitting method based on empirical Sloan Digital Sky Survey Stripe 82 RR Lyrae data to identify RR Lyrae candidates in the NGVS data set. We eliminate several hundred suspected quasars and identify 180 RR Lyrae candidates with heliocentric distances of ∼20–300 kpc. The halo stellar density distribution is consistent with an r −4.09±0.10 power-law radial profile over most of this distance range with no signs of a break. The distribution of ab-type RR Lyrae in a period–amplitude plot (Bailey diagram) suggests that the mean metallicity of the halo decreases outward. Compared to other recent RR Lyrae surveys, like Pan-STARRS1, the High Cadence Transient Survey, and the Dark Energy Survey, our NGVS study has better single-epoch photometric precision and a comparable number of epochs but smaller sky coverage. At large distances, our RR Lyrae sample appears to be relatively pure and complete, with well-measured periods and amplitudes. These newly discovered distant RR Lyrae stars are important additions to the few secure stellar tracers beyond 150 kpc in the Milky Way halo.

Rancang Bangun Pengemasan Produk Kacang Goreng Otomatis Berbasis Mikrokontroler

The working system of this Automatic Fried Bean Product Packaging tool uses Arduino Mega2560 as a microcontroller, then a screw on the funnel to accelerate the descent of the product into the packaging plastic and prevent blockages, infrared sensors to detect product availability in storage containers. The tool made uses volume measurements to minimize error on the scales using a load cell sensors. The type of research used in making the final assignment is action research which is carried out carefully, logically and systematically. The conclusions of this research are (1) The system can detect the supply of fried peanuts in the funnel/silo using infrared FC-51 sensor with a distance range of 1 – 8 cm. (2) The system can read the mass input selected by user, namely 75 g, 100 g, and 150 g with a push button and displayed through the LCD. (3) The system can fill the fried peanuts into packages according to the mass that has been set through the KY-008 laser sensor and laser receiver, using the tube volume formula with a percentage error of 4.5% for a mass of 75 grams, 3.83% for a mass of 100 grams, and 5.41% for a mass of 150 grams. (4) The system can perform the package closing process using servo motors, heating elements, and stepper motors. The duration of time required by the heating element in gluing the plastic ranges from 3 to 4 seconds.