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The pandemic has shown viral capacity in massive spreading and environmental adaptability for years. It has infected millions of people with several symptoms leading to millions of mortality worldwide. Its fast-spreading capacity, unpredictability prognosis and variants appearance are leading big threats, particularly to the health facilities. Therefore, appropriate health protection equipment, including adequate and safe decontamination procedures, is required to support the facilities in overcoming potential future contaminating pathogens. Unfortunately, only a few studies evaluated the utilization of medical decontamination devices. Rapid and massive manufacturing of decontamination devices without further and adequate post-monitoring may have several side effects. Therefore, careful and continuing consideration and evaluation studies are necessary to maintain the devices' quality and performance. This study aims to evaluate the ability of UV lights as laboratory devices to impair viral components. Clinical RNA samples were provided by the COVID-19 laboratory examiner as blinded samples without any subject information. SARS-CoV2 RNA (a viral representative RNA material) extract was exposed to 5 different UV lights, with different distances and exposure duration. The exposed RNA was then sequentially used as a cDNA template and DNA amplification. Amplification products were visualized by electrophoresis and densitometry analysis. Visualization and densitometry analysis showed that the UV-LED Nichia NCSU 334 had the most significant disruptive ability among the tested lights. The exposure duration and distance altered the effectiveness of UV light in damaging viral genetic material. UV-LED Nichia NCSU 334 could be suggested as an alternative UV source in a UV light-based disinfection system. This study proposed direct evidence for evaluating decontamination devices to ensure the effectiveness of the decontamination process. [ABSTRACT FROM AUTHOR]

Fuzzy K-Nearest Centroid Neighbor is the classification method used to predict test data that uses sample membership values that are not yet clear to all available classes. Chebyshev distance is described because of the best distinction among vectors alongside any coordinate dimension. In other words, it's the most distance alongside one axis. Due to its nature, it's frequently known as Chessboard distance because the minimal variety of actions wanted through a king to head from one rectangular to any other is the same as Chebyshev distance. This study aimed to determine the effect of Chebyshev distance on FKNCN performance. The research shows that using the Chebyshev distance produces higher accuracy than using the Euclidean distance, so it improves the performance of the FKNCN. [ABSTRACT FROM AUTHOR]

Second order statistical moments of the temporal spectrum of scattered ordinary and extraordinary electromagnetic waves in the equatorial ionosphere are investigated in ray (-optics) approximation using the stochastic transport equation. Temporal spectrum broadens and its maximum is displaced due to anisotropy factors of elongated plasmonic structures, velocity of a turbulent plasma flow and anisotropic ionospheric conductivities. Statistical moments not contain sign of an absorption and valid for both active random media and collision magnetized plasma. Temporal pulsations of a turbulent plasma flow and anisotropy of ionospheric conductivity have an influence on the evaluation of the temporal spectrum of the scattered waves at different distances propagating in the terrestrial atmosphere. Precursor in the temporal spectrum is revealed in the equatorial ionosphere. An approximate expression of the temporal spectrum of the wave as a function of the source-field point distance (or propagation distance) is obtained for the case in which the characteristics frequency of the source is much greater that of the medium. Numerical calculations are carried out using the experimental data. Investigations of space-time fluctuations of electromagnetic waves radiation are of essential interest for radio astronomy and atmospheric physics. [ABSTRACT FROM AUTHOR]

The growing demands for vegetable oil have indirectly affected human health with the trace of 3-monochloropropane-1,2-diol (3-MCPD) found in the oil. This is probably due to 3-MCPD can be considered carcinogens to humans. Herein, this research study focused on investigating the effect of distance of Ultraviolet type C (UVC) lamp to the reactor, stirring speed, and initial concentration of 3-MCPD. The samples were analyzed using UV-Visible (UV-Vis) Spectrophotometer and Fourier Transform Infrared Spectroscopy (FTIR) to determine the concentration and the functional group of 3-MCPD, respectively during the process. From this research study, up to 80.7% degradation of 3-MCPD was achieved under these conditions; 10 cm distance of UVC lamp (60 W) to 3-MCPD, without stirring the medium at temperature of 60 ˚C for 2 hrs. Besides that, the removal rate of 3-MCPD was at its highest (426.7 ppm/hr) when 5000 ppm of 3-MCPD was employed in the process. Therefore, it can be highlighted that the photocatalytic reactor used in this research study provides sufficient energy to break the bond between carbon and chloride ions in the 3-MCPD contaminant. [ABSTRACT FROM AUTHOR]

The current study targets to examine the influence of dimples on the hydro-thermal output performance of a serpentine mini-channel heat sink. In the current study, the effect of various dimples diameters namely 1.5mm, 2mm and 2.5 mm and different distances between dimples of 5mm, 7mm and 9mm are investigated. The numerical results of the present study are obtained by using 3D (ANSYS Fluent program). To ensure of numerical result, comparison with experimental finding from literature review was conducted. The compared between experimental and numerical finding indicated and a good convergence. Moreover, the results show that diameter of dimples influence on the performance of hydro-thermal is more than influence of distance between dimples. In addition, the effect of dimples diameter on overall performance factor (OPF) is higher than the effect of dimples distance. Among these models under study the model of diameter 2.5 mm and distance 7 mm are the optimum model regarding overall performance factor. [ABSTRACT FROM AUTHOR]

The aim of our study was to determine effect of distance education during pandemic COVID19 on physics knowledge of the first-year medicine students. Test results from academic years 2019/2020 (360 students) and 2020/2021 (465 students) were evaluated. Methods of descriptive statistics, t-test and one -way ANOVA were used. All tests were solved in the MOODLE environment. Maximum score was 100 points. Presence teaching, academic year 2019/2020: In the first continuous test students achieved 79.23 ± 7.22 points in average. In the second continuous test students gained an average of 77.17 ± 7.82 points. The average score on the written part of exam after completing biophysics was 78.46 ± 6.60. Distance teaching, academic year 2020/2021: In the first continuous test students after distance learning achieved 77.22 ± 8.19 points in average. In the case of the second continuous test the average gain was 83.73 ± 7.47 points. In the written part of the exam in biophysics after completing the course, students obtained an average of 81.08 ±6.67 points. Using one-way ANOVA analysis, we found that in the case of presence teaching, students' performance was balanced, there was no statistically significant difference between the results of individual tests (p = 0.1). The results of students taught in the distance form show statistically significant differences between the individual tests, which signals unbalanced performances (p <0.001). [ABSTRACT FROM AUTHOR]

Cadmium sulfide (CdS) nanofiber in thin films form have been prepared on flexible ITO coated Polyethylene Terephthalate (PET) substrate via chemical bathe deposition technique. X-Ray Diffractometer used for the structural analysis of the CdS nanofiber thin films and the topographical image characterized by using an Atomic Force Microscope (AFM). AFM studies showed that the average diameter of the CdS nanofiber ∼250 nm with length several micrometers. The electron field emission property of CdS nanofiber thin films have been carried out for different anode to cathode distance. It was found that the threshold field decreases from 4.2 - 2.5 V/μm when the anode to sample i.e., nanofibers thin film distance increased from 100 to 200 µm. The emission current density with anode to sample distance were calculated and tried to explain the mechanism. [ABSTRACT FROM AUTHOR]

The paper presents a 2D model of a system for contactless inductive energy transmission. Graphical dependences for the inductance of the transmission coil on the frequency, on the magnetic permeability of the concentrators and on the distance between the coils are obtained. In addition, results for the power of the transmitting coil and the dependence of the induced voltage in the receiving coil on the frequency of the power supply are shown. An analytical model of an air transformer is used to explain the numerical results. [ABSTRACT FROM AUTHOR]

In this paper we will discuss how to determine the distance between two convex sets in Hilbert space. This problem came from measuring the shortest distance between two cities, which consider by determining the distance between two buildings in each city. In this problem, the cities are considered as the sets and the buildings are points. Furthermore, based on this problem, it is generalized to determine the distance between two convex sets in Hilbert space that solved by optimization concept by measuring maximal distance between two parallel supporting hyperplanes that separate them. Therefore, it is given some example to understanding, such as the distance between two normed balls, ellipsoids, and linear varieties. [ABSTRACT FROM AUTHOR]

The distance vertex irregular total k-labelings on graph G(V, E) is a mapping f : V (G) ∪ E(G) → {1, 2,..., k} such as for every u, v ∈ V (G) and u ≠ v, the weight of u is not equal to the weight of v. The weight of any vertex u ∈ V (G) evaluate based on the neighborhood of vertices and the neighborhood of edges of u. The total distance vertex irregularity strength of G denote by tdis(G), is the minimum of the biggest label k over all distance vertex irregular total k-labelings of G. In this paper, we determine the total distance vertex irregularity strength of fan and wheel graphs. [ABSTRACT FROM AUTHOR]

Despite of the hardness of finding the distance distribution of a code, it is one of the important topics in coding theory. By knowing the distance distribution of a code, we can measure the performance of the code. The development in satisfiability (SAT) theory has been improved recently. The modern SAT solver is performing much better in terms of computational efficiency. Unfortunately not all problems could easily be expressed as a propositional satisfiability problem, and some could lead to a very complex representation. This problem gives rise to a new topic called satisfiability modulo theory (SMT). The idea is to restrict the fragment of first-order logic to some logical background theory. By doing this, it can solve more varied problems efficiently using the SAT solver engine. The constrained system, especially the 1-D constraint, has proved to be beneficial for the magnetic tape recording. Recent de- velopments in data recording technology allows us to store data in a 2-D format, such as the holographic recording technology. However, in contrast with the constrained sequence, the theory is not yet well-developed. In this paper, we utilize the power of the SMT solver to find the distance distribution of 2-D binary constrained systems. [ABSTRACT FROM AUTHOR]

Cellular automata-finite difference framework is employed to estimate the influence of the hatch distance on the resulting microstructure of 316 L austenitic stainless steel fabricated by selective laser melting. The grain structure is found to be significantly affected by the hatch distance, including both the grain morphology and crystallographic texture. The smaller the hatch distance, the more severe the texture, the smaller the number of fine grains observed in the microstructure pattern, and the more pronounced the Goss texture component in the case of employed process parameters. [ABSTRACT FROM AUTHOR]

Consideration of energy consumption and its impact on the environment has been driving the heating, ventilating, and air conditioning (HYAC) industry to develop and test more energy-efficient units. The Air Handling Unit (AHU) is one of the important components of the HYAC system that has undergone a lot of improvements in terms of energy efficiency through increased coil surface area, thus its unit size. Yariation of AHU models requires energy performance testing and rating standard which is currently guided by ASHRAE Standard 37. The standard provides a limited guideline on the distance between the floor and the inlet duct length of the vertical AHU units which, although giving flexibility during testing, can lead to the variation of testing results of the same unit. This study uses a computational approach and experiment result to examine the effect of floor distance on the air velocity profile and fan power of a vertical ducting arrangement for an AHU unit. The unit geometry specification is obtained from the experimental campaign at Oklahoma State University, USA as part of ASHRAE research project. The results indicate that for all cases the air velocity 1 m downstream the opening is well distributed. The experiment also shows that different floor distances do not have a big influence on fan power. [ABSTRACT FROM AUTHOR]

A kind of motor vehicle emission is particulate matter or PM. Of all the types of PM, some PMs have a diameter of less than 2.5µm or PM2.5. PM2.5 are recognized as the pollutants that harm human health. An effort that can be made to reduce this emission is by developing a PM2.5 filtration system. This research developed the PM2.5 filtration system based on high voltage direct current with varied of gap distance that was applied on motorcycles. The filters were made of four aluminum plates with a thickness of 0.15 mm arranged as anode and cathode probes installed before an orifice of the outlet. There were four variations in different gap distances between the plates: F1 with a distance of 14 mm, F2 with a distance of 12 mm, F3 with a distance of 10 mm, and F4 with a distance of 8 mm. The voltage that was originated from the battery by 12 V was converted 400Volt with a signal conditioning circuit. The filtering efficiency was calculated by measuring PM2.5 concentration before and after passing through the filter using Kanomax 3443 Digital Dust Monitor. The result showed that the filter could reduce PM2.5 concentrations from 63% to 70% depending on the gap distance between the plates. [ABSTRACT FROM AUTHOR]

The glass fibre reinforced polymer (GFRP) composites are widely used in critical parts of the aircrafts. The inter-laminar and intra-laminar shear strength of GFRP laminated composite structures are weak due to presence of voids in matrix, tools dropping during maintenance, birds hitting, lightning strikes. This paper investigates the effect of kevlar thread pitch distance in chopped GFRP composite laminates. The inter-laminar and intra-laminar shear strength of the composites was improved by using kevlar thread stitching in composites. This study focuses on the effect of kevlar thread stitching in chopped GFRP composites with different orientation and pith distance. The experimentation started with 1-cm pitch distance was performed in the direction of longitudinal, transverse and both directions of laminated composites were subjected to three point flexural tests. The result revealed that the longitudinal direction stitching having better mechanical properties compared to transverse and both direction. Further, in longitudinal direction, 1-cm, 2-cm and 3-cm pitch distance of composites were subjected to three point flexural tests. The result inferred that the 3 cm pitch distance of stitching in laminates having better damage resistance and mechanical properties compared to other configurations. [ABSTRACT FROM AUTHOR]

Multi-fuzzy set theory is an extension of fuzzy set theory, which deals with the multi dimensional fuzziness. It was introduced by S. Sebastian and T.V. Ramakrishnan in 2010. Thenceforth, the theory is developing through many angles. This paper proposes the notion of distance measure of multi-fuzzy sets. Furthermore, the paper explores some results related to this concepts. [ABSTRACT FROM AUTHOR]

Let G be a connected graph of order at least two. We study about monophonic radius- distance monophonic set and define a set for an edge called edge rm-distance monophonic set of G. An edge rm-distance monophonic set of different kinds of graphs are found and verified. A new parameter edge rm- distance monophonic number is introduced and some bounds are found for several graphs. A relation between rm- distance monophonic number and edge rm- distance monophonic number of G is found. A main result, for every two positive integer a and b such that 3≤ a≤b, there is a connected graph G with a as a rm- distance monophonic number and b as an edge rm- distance monophonic number of G is proved. [ABSTRACT FROM AUTHOR]

Rumpin airfield is located in Bogor, West Java with latitude -6.373 and longitude 106.622 degrees with ICAO code WI1C. Rumpin airfield is used for civil and military purposes. The problem is the runway marking of safety not yet shown. To support the flight activities especially for take-off and landing, needed the calculation of declared distance. Declared distance is operational distance to notify the Pilot for take-off, landing and cancellation take-off safely. This Study introduces an approach to know the value of Take-off run available (TORA), Take-off distances available (TODA), Accelerate-stop distance available (ASDA) and Landing distance available (LDA). The calculations are carried out in accordance with Director General Decree No. 39 Year 2015 concerning Manual of Standard Civil Aviation Safety Regulations (CASR) Part 139 regarding Airports (Aerodromes). The calculations results are TORA, ASDA and LDA about 1111 m and the TODA about 1151 m. The runway qualifications in accordance with ICAO - Annex 14 Vol.1 Aerodrome Design and Operations 2015 using runway type B. [ABSTRACT FROM AUTHOR]

Theoretical simulations on single dielectric microspherical particles illuminated by plane wave are performed systematically to find out the key parameters for (i) generating elongated photonic nanojet and (ii) obtaining more focal length of the microsphere or working distance. These simulations are performed using analytical theory proposed by Aden and Kerker [1]. In addition, the dependence of the intensity distribution inside and outside the core-shell particles, length and width of the PNJs on the refractive index of the surrounding medium is studied in detail. The difference in the PNJs of the microparticles illuminated with resonant and non-resonant illuminations is also investigated. [ABSTRACT FROM AUTHOR]

The behavior of littering is mostly done by Indonesian people. Community indifferently throws out garbage not in the place provided. Seen, in public area, there is a lot of garbage scattered out. This makes the environment dirty, uncomfortable and unhealthy. There needs to be an effort to change the bad habits of this society. By way of being reminded when people throw litter. So that there is a reminder that it will form a mindset from the community. This can change the mindset, to care more about the environment. The camera is used as a sensor to detect people who litter. Image processing needs to be done to determine the next step. The camera is placed in an upright position, also affecting the detection area, where the limited camera resolution makes the detection distance limited. Meanwhile, the position of the sun also contributes to changing the resolution of objects. From the results of the experiments, the detection distance between morning, afternoon and evening has a different value. At distances less than 120 meters and more than 280 meters were not detected. and the highest solar intensity value just above the equator, it’s in more than 950x100 luxs. [ABSTRACT FROM AUTHOR]

Levitation of two-dimensional (2D) ordered arrays of microdroplets over hot liquid surfaces has been studied in several previous papers. This phenomenon is relevant for many practical applications, such as spray cooling or synthesis of chemical components by containerless process. However, the mechanism of interaction of drops with each other in the 2D array has not yet been clarified. In this connection, the aim of this work is to determine the dependence of the distance between microdroplets on their size and on the number of drops in the array. It was found that the average distance between the drops grows with increasing diameter of the drops. According to the results of the experiment, for the number of droplets N less than about 7, the average distance between the drops practically does not change, however for N>7 the distance between the drops starts to decrease with N. [ABSTRACT FROM AUTHOR]

The asymptotic solution of the problem of an axisymmetrical vortex generated by a rotating infinitely extended circular cylinder in a viscous heat-conductive ideal gas is obtained at large times for the case of large Reynolds numbers. The non-monotonic behaviour of circulation by the distance from the center of the vortex is explained. A number of conditions, guaranteeing that a circulation is higher than in the incompressible fluid case, is identified. The influence of the Mach number on the solution is studied. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDH) have gained high attention as a promising material to be applied in various fields owing to their flexibility and controllable interlayer anion and composition. In this study, NiAl based layered double hydroxides were successfully prepared by the coprecipitation method. Furthermore, its intercalated form was prepared by an ion-exchange method using (α-SiW12O40)4- anion. The prepared materials were characterized by X-ray diffraction and FT-IR. X-ray diffraction analysis showed that after intercalated by (α-SiW12O40)4-, the typical diffraction peak of NiAl LDH shifted to the lower angel, indicating that the interlayer distance expanded. The pristine NiAl LDH showed a typical pattern at the diffraction angle of 11.52° with basal distance 7.66 Å. While, after intercalated by (α-SiW12O40)4- the diffraction angle of the typical pattern moved to 8.52° with the basal distance increased to 10.36°. [ABSTRACT FROM AUTHOR]

Over the past few years, multi-rotor drones have been widely used for the both military and civilian purposes. In this paper, we are taking steps for finding a method to calculate and keep the distance in order to make the ranges of photos of every UAVs connected according to the lens and flight height. Finally, we succeeded to develop the distance maintaining calculation method via implementing angel of view formula. [ABSTRACT FROM AUTHOR]

In 1984, Khan et al. [3] established some fixed point theorems in complete and compact metric spaces by using altering distance functions. In 2017, Gordji et al. [2] described the notion of orthogonal set and orthogonal metric spaces. In their work, they held a generalization of Banach fixed point theorem in this interestingly-defined construction and in addition, applied their acquired results to demonstrate the existence of a solution of an ordinary differential equation. In this paper, some fixed point theorems on orthogonal metric spaces via altering distance functions inspired by [3] and [2] are presented. [ABSTRACT FROM AUTHOR]

The reciprocal degree distance (RDD) is a widely known description which is a weighted version of Harary index. This article is attain the value of RDD of different types of cactus. [ABSTRACT FROM AUTHOR]

The Reverse distance degree invariant denoted by RDI is defined for a connected graph Λ as RDI(Λ) = ∑r,s∈V(Λ) dgΛ(r)+dgΛ(s)/distΛ(r,s). The new graph invariant named improved reverse distance degree invariant is defined as I...t(Λ) = ∑r,s∈V(Λ) dgΛ(r)+dgΛ(s)/distΛ(r,s)+t, t ≥ 0. This paper is obtain the exact formulae for the improved reverse distance degree invariant and reverse distance degree invariant of corona product, rooted product, splice product and link product. [ABSTRACT FROM AUTHOR]

In the recent era, the coloring of the graphs is arousing the attention of researchers. Among the mathematical models, coloring technique plays a vital role in a broad range of applications in real life problems and it solves several complexiti es of computer networks. In this paper, prime coloring and its chromatic number of unit distance and non crossing Graphs are depicted and its results are validated with few theorems [ABSTRACT FROM AUTHOR]

In this present work, taking full advantage of MNPBEM toolbox, the optical properties of gold dimers have been simulated with an emphasis on the extinction spectra. The plasmon resonance wavelength of coupled gold nanospheres as a function of interparticle distance has been studied by varying the surface-to-surface distance from 100 nm to 500 nm. Two distinct regimes are determined namely near-field and far-field, which depend on the distance between the gold dimers and also on the orientation of the nanoparticle pair with respect to the polarization axis of the incident light. When the incident light is polarized along the dimer axis, the wavelength corresponding to the maximum extinction first blueshifts with increasing gap, and then red-shifts as the particle separation are further increased. However, for the perpendicularly polarized excitation, the increase in the separation distance leads to non-monotonic shift in the plasmon resonance wavelength. From this observation, it reveals that the far-field interaction as well as the retardation effect for large particles cannot be ignored as it leads to the damping of the plasmon oscillation, with more obvious effect being associated with perpendicular polarization. [ABSTRACT FROM AUTHOR]

The correspondence principle of linear viscoelasticity is used to derive the displacement fields due to a single force in an elastic half-space overlying a viscoelastic half-space. The results are valid for arbitrary values of the relaxation time and a change in the rigidity of the two half-spaces. The variation of the viscoelastic displacements with the epicentral distance as well as with the different relaxation time and a change in the rigidity of the two half-spaces are studied and shown graphically. [ABSTRACT FROM AUTHOR]

In this paper, preliminary level designing of a tilt rotor UAV and tilting mechanism, are presented. Tilt rotor aircraft is a VTOL which offers more speed and comfort for payload than other VTOLs. A conceptual configuration for tilt rotor based remote controlled (RC) plane has been developed. Three tilt rotor mechanisms have been devised, modeled in CATIA V5 and analyzed with the help of the multibody dynamics simulation software ADAMS and details of the feasible mechanism were found out. [ABSTRACT FROM AUTHOR]

The characterization of the whole solar field of a solar tower power plant is a time consuming labor that has to be performed to know the optical quality of each heliostat in the field. This allows to correct some deviations of each heliostat, leading to an improvement in its individual performance, and thus, improving the final performance of the whole field. The current methodology to characterize the optical quality of a heliostat is based on using a lambertian target, in which the solar beam is focused and its reflected radiation is captured using cameras. This leads to important measurement inaccuracies due to the non-uniformity of the lambertian target and the behavior of the camera. But the fact that the sun beam can overflow the size of the target, and its power density can be almost in the order of the ambient light, implies that a huge part of the heliostats in a plant cannot be well-characterized by these systems. These issues are even more important taking into account that plant size tends to grow even larger, increasing the distance of the furthest heliostats, and that small heliostats begin to be introduced in solar fields, whose reflected power is lower than that of common heliostats. Those issues will be overcome thanks to a new measurement system based on a non-tracking way to scan the sun spot, using an array of optoelectronic detectors which can be installed in new plants and even in plants that are now in operation. [ABSTRACT FROM AUTHOR]

The paper deals with the problem of accuracy increasing of small distance changes measurements in radar level gauges with frequency modulated continuous wave signals. In the considered task advantages of estimation of time delay differences as indirect parameter of beat signals full phase are shown. This approach is shown to be more informative in comparison with traditionally applied estimators of time delay difference, which based on a frequency and initial phase estimation as separate parameters. For the model of beat signal of level FMCW radar in the typical interference conditions it is proposed to use the phase-based estimator which was investigated by us in the previous works. The obtained results shown that in the considered conditions the proposed approach allows one to reduce the variance and bias of level increments estimates by several times in comparison with traditionally used estimators. [ABSTRACT FROM AUTHOR]

This study aimed at characterising and analysing the geometry of bark in the species Fraxinus angustifolia Vahl. (ash) through fractal analysis. Binarised images of the ash bark captured from a caption distance between 10 and 50 cm every 5 cm were analysed through box-counting. Depending on the pixels analysed (black and white – BW, black + black and white – B+BW, and white + black and white – W+BW) we obtained fractal dimensions DBW, DB+BW, and DW+BW, respectively. There was a high positive correlation between fractal dimensions and image caption distance: r = 0.895 for DBW, r = 0.787 for DB+BW, and r = 0.820 for DW+BW, respectively. The relationship of interdependence between fractal dimensions and image caption distance was described by second degree polynomial equations with statistic safety, as follows: R² = 0.882, p = 0.00165, F = 22.371 for DBW, R² = 0.918, p = 0.00055, F = 33.498 for DB+BW, and R² = 0.932, p = 0.00031, F = 41.292 for DW+BW, respectively. [ABSTRACT FROM AUTHOR]

One of the problems that cause damage to the stilling basin on the downstream of weir or dam is the tail water depth (TW depth) conditions which are not in accordance with the stilling basin’s boundary conditions. This conditions cause the hydraulic jump to jump off the stilling basin and higher flow velocity. Baffled blocks are blocks with a certain pattern installation that are installed on the stilling basin. These blocks have functions of generating hydraulic jumps and decreasing flow velocity. Therefore, this research was conducted to determine the effect of lateral and longitudinal distance of baffled block on flow velocity for various tail water depth conditions. Four models of stilling basin are made by changing the lateral and longitudinal distance of baffled block. The original pattern of baffled block is only effective for TW depth that matches boundary conditions (TW depth = 1.0 D2). Thus, the change in lateral baffled block distance so that it is located between chute blocks could reduce the TW depth to 0.9 D2. At 0.9 D2 TW depth conditions, this pattern could also reduce the flow velocity 0.35% more effectively than the 1.0 D2 TW depth condition. Due to, the change in longitudinal distance, the distance between baffled block and chute block is shorter, causing the flow velocity becomes unstable. It also causes the hydraulic jump to be higher so that the 1.0 D2 TW depth conditions are no longer effective. Thus, the change in longitudinal distance so that the distance between baffled block and chute block to be longer could stabilize the flow velocity at 0.9 D2 TW depth conditions. But, this pattern is able to reduce the flow velocity at 0.9D2 TW depth condition by 0.75%, which is lower than 1.0 D2 TW depth condition. [ABSTRACT FROM AUTHOR]

A vertex v ∈ V(G) that lies at the same distance from at least two distinct vertices u and w is said to be a distance similar vertex with respect to u and w. A set S ⊂ V(G) of vertices is said to be a distance similar set when each v ∈ S is distance similar to all vertices in V(G) - S. Maximum cardinality of a non-trivial distance similar set is called the distance similar number of graph G and is denoted as ds(G). This paper aims to evaluate ds(G) for some special family of graphs. [ABSTRACT FROM AUTHOR]

Here we study light-induced interaction of several dielectric particles above a hyperbolic metamaterial. It is shown, that both surface and volumetric modes of the substrate define distances between interacting particles, beyond the diffraction limit. Moreover, by varying the thickness of the metamaterial substrate it is possible to tune magnitude of the optical force and distances between the particles. [ABSTRACT FROM AUTHOR]

In this paper, we define soft D− metric spaces and give some fundamental definitions. In addition to this, we define a soft Δ− distance on a complete soft D− metric. [ABSTRACT FROM AUTHOR]

This work explores the correlations of modern physics and the (Orthodox Christian) theology, through the analysis of space and light. In modern physics, the space we think we occupy is nothing but constant repulsion of point-like particles. "Space" tends to concepts such as separation - demarcation, distance - range, space - dimension. While light with bosonic nature tends to gather and unite instead of separate, it "lives" out of time and space instead of decay and isolation. On the other hand, Theology teaches that selfishness is what separates us, separate will that holds us in distance, sin that depart us from our original destination. The proposition: co-space, co-fit, co-placement (forgiveness, “sin-horesi” in Greek) and love that is union, coupling, and leads to salvation (hold in one unit, “sotiria” in Greek), which tends to keep man as one unit through reunion with the Creator. In this sense, the characteristics of light in physics described above are correlated. [ABSTRACT FROM AUTHOR]

We used the SDSS magnitudes of about 1.5 million F and G type main-sequence stars with metallicity and distances and estimated vertical metallicity gradients for middle/high Galactic-latitude fields of the Milky Way. The vertical metallicity gradients estimated for stars with three different galactocentric distance intervals. Thin disc with a vertical metallicity gradient -0.308±0.018 dex kpc-1, is dominant only in distance interval 6 < R ≤ 10 kpc, while thick disc could be observed in the distance intervals 6 < R ≤ 10 and 10 < R ≤ 15 kpc with vertical metallicity gradients are d[Fe/H]/dz = -0.164±0.014 and d[Fe/H]/dz = -0.172±0.016 dex kpc-1, respectively. Vertical metallicity gradients for stars in distance interval 15 < R ≤ 20 kpc, where the halo component dominates, is almost zero. Metallicity gradients obtained in this study are also compared with the Galaxia model. The comparison is a good agreement between the two sets of vertical metallicity gradients for the thin disc and halo, while they are somewhat different for the thick disc. [ABSTRACT FROM AUTHOR]

Determination of the best distance, namely the closest distance and in the shortest time to reach a destination appropriately, has been applied in daily life. The determination of the best distance can be applied on robot trajectory so that robot can reach its destination quickly and appropriately without taking much time in robot contest, such as Indonesian Smart Robot Contest (KRCI). The difficulties to determine the closest distance occur due to the existing trajectory alternatives. In this aspect the reliability of a robot is tested and contested. Every year there are many robot contests either local, national, or international scale. Robot trajectory is a place or points passed by moving objects. This study used Simple Additive Method (SAW) method to find the closest distance by finding the value of alternative tracks existing on the trajectory. Determination of the closest distance on robot trajectory gives facility for the users to find the closest distance of a robot trajectory so as to input the correct algorithm in robot to reach the destination quickly and appropriately. [ABSTRACT FROM AUTHOR]

The aim of this paper is to prove some tripled fixed point theorems for some types of generalization of contraction mappings under the continuity condition in cone metric spaces with c-distance. [ABSTRACT FROM AUTHOR]

Epidemiological spreading does not only happen from person to neighbouring person but often over wide distances, when infected but asymptomatic persons travel and carry infection to others over wide distances. Superdiffusion has been suggested to model such spreading in spatially restriced contact networks, i.e. there is still a notion of geographical distance, but spreading happens with high probability proportional to large distances. From fractional calculus several ways of describing superdiffusion are know. Here we investigate the representation in Fourier space and which is easily generalizable to higher dimensional space in order to compare with stochastic models of epidemiological spreading. [ABSTRACT FROM AUTHOR]

The standard Higgs mechanism employed in the Standard Model (SM) for electroweak symmetry breaking, relies on a homogenous Higgs vacuum expectation value (v.e.v.), i.e. a vacuum that does not depend on the position or the time coordinates. However, other non-homogeneous structures could also be considered, either at long or short distances. For instance, spatial variations of the Higgs v.e.v. on cosmological scales, would induce variations of the fundamental constants, and are severely constrained. Other possibilities, such as a discrete microscopic structure of the Higgs vacuum, or a confined Higgs mechanism associated with a strongly interacting Higgs sector, could be tested and give some light on the electroweak-scale contributions to the cosmological constant. [ABSTRACT FROM AUTHOR]

The cosmological constant Λ affects gravitational lensing phenomena. Related effect can be studied in the framework of the Schwarzschild-de Sitter space-time in the weak deflection limit. The main contribution of Λ can be accounted for by a proper use of angular diameter distances. For near lenses and static observers, unresolved images are slightly de-magnified, the radius of the Einstein ring decreases and the time delay increases. The effect is however negligible. Two novel contributions, which show up in a cosmological context, are also discussed. First, a term δα⁁ = 2mbΛ/3 has to be added to the bending angle, where m is the lens mass and b the impact parameter. Second, Λ brings about a difference in the redshifts of multiple images. Both effects are quite small for real astrophysical systems, δα⁁Λ<=0.1 μarcsec and Δzs<=10-7. [ABSTRACT FROM AUTHOR]

A relative distance-oriented phase unwrapping algorithm is presented in this paper. Considered the wrapped phase value and modulation distribution of the neighboring pixel, a relative distance of two adjacent pixels is calculated and localized in a complex coordinates, in which the relative distance tree will be composed by all the relative distances and will be used to determine the optimized path of phase unwrapping. The smaller relative distance shows that the phase difference between the two corresponding pixels is very small and the phase data waiting for unwrapping is more reliable. The closer the relative distance is, the more success the phase unwrapping will achieve. Combining the minimum spanning tree algorithm, the phase unwrapping order of each pixel can be determined and the whole phase unwrapping path can also be given. The phase unwrapping path is always directed from the minimum distance value to the greater one. Consequently, this algorithm could avoid error propagating in the phase unwrapping. The errors could be limited in the minimum local region in worst case and the error probability of the phase unwrapping is as low as possible. The physical significance of the relative distance and the fully algorithm for phase unwrapping are proposed in this paper. The result of the experiment show that this new algorithm is feasible and effective, it could control the path avoid crossing the poles, branch-cut and the shadow in the phase unwrapping. [ABSTRACT FROM AUTHOR]

Gamma ray bursts (GRBs) are high energy photons detected during a short interval of time. They are signs of the most energetic events in the universe. Photons detected show a non thermal spectrum, very well described by the peak energy and two smoothly connected power laws with different slopes or indices. This spectrum is named Band spectrum and serves actually as the most important source of information on their physical origin. It characterizes not only the overall emission, but also the instantaneous one, found in small successive intervals of time during the event. The time-resolved spectra show an obvious evolution in energy, which is generally accepted and supported by several arguments. There is also some evidence in measuring a kind of evolution in slope parameters, which would be considered as a serious source of information for the physical mechanism. In this work we try to examine the limit in observation bands, which we suspect as a reason for the apparent variation in time of spectral indices. Our work is based on a numeric and certified code. We simulate GRBs assuming synchrotron emission in the internal shocks model. For each time-resolved spectrum we find spectral parameters based on the Band function. [ABSTRACT FROM AUTHOR]

We present some results of an observational and theoretical study on unresolved stellar systems based on the Surface Brightness Fluctuations (SBF) technique. It is shown that SBF magnitudes are a valuable tracer of stellar population properties, and a reliable distance indicator. SBF magnitudes, SBF-colors, and SBF-gradients can help to constrain within relatively narrow limits the metallicity and age of the dominant stellar component in distant stellar systems, especially if coupled with other spectro-photometric indicators. [ABSTRACT FROM AUTHOR]

We only see a small fraction of the matter in the universe, but the rest gives itself away by the impact of its gravity. The distortions from pure Hubble flow (or peculiar velocities) that this matter creates have the potential to be a powerful cosmological tool, but are also a nuisance for extragalactic astronomers who wish to use redshifts to estimate distances to local galaxies. We provide a quick overview of work on the local peculiar velocity field, discussing both simple spherical infall models, non-parametric modeling using redshifts surveys, and full velocity and density field reconstruction from peculiar velocities. We discuss results from a multiattractor model fit to data from the SFI++ sample of peculiar velocities—the best peculiar velocity data currently available. We also talk about the future of samples for the study of the local velocity field, especially the 2MASS Tully-Fisher (2MTF) survey. [ABSTRACT FROM AUTHOR]

We clarify the link between lags and spectral evolution from a simple linear analysis of the pulse shape around maximum. We then discuss the physical origin and validity of the lag-luminosity relation and discuss its use as a distance indicator. [ABSTRACT FROM AUTHOR]