Positive X-axis Research Articles

Similarity Measurement for Graph Data: An Improved Centrality and Geometric Perspective-Based Approach

How to make a precise similarity measurement for graph data is considered as highly recommended research in many fields. Hereinto, the so-named graph data is the coalition of patterns and edges that connect patterns. By taking both of pattern information and edge information into consideration, this paper introduces an improved centrality and geometric perspective-based approach to measure the similarity between any two graph data. Once these two graph data are projected into a plane, the pattern distance can be calculated by Euclid metric. With the help of the area composed by length of each edge and angle that constructed by the positive X-axis and the edge, the area-based edge distance is computed. To get better measurement, position-based edge distance is used to modify the edge distance. Up to now, the global distance between any two graph data can be determined by combining the above mentioned two distance results. Finally, the letter dataset is applied for experiment to examine the proposed similarity approach. The experimental results show that the proposed approach captures the similarity of graph data commendably and gets a tradeoff between time and precision.

Propagation of integral and fractional perfect vortex beams in a gradient-index medium.

The analytical expressions for the complex amplitude of integral and fractional perfect vortex (PV) beams propagating in a gradient-index (GRIN) medium are derived. The intensity and phase distributions, propagation trajectories, Poynting vectors, and the effects of topological charge and refractive index at the medium axis on the intensity of both beams in the medium are numerically investigated. It is shown that both beams propagate periodically in the GRIN medium with alternating spot focusing and reconstruction. Unlike the integral PV beam, the fractional PV beam has a dark line in intensity profiles and a line edge dislocation in phase distributions along the positive x-axis. These properties persist during the beam propagation in the GRIN medium. Moreover, the topological charge and the refractive index at the medium axis have little effect on the intensity of the PV beam propagating in the GRIN medium. The results presented in this paper may be useful for the application of integral and fractional PV beams in optical guiding and optical communications.

Evaluation of the Development Strategies Village Breeding Center Peranakan Ongole (PO) Cattle Based on Swot Analysis

The research revealed that the appropriate strategy for the development of local cattle is influenced by both internal and external factors, such as the age of farmers, the educational level of farmers, the experience of cattle, the main job of farmers, availability of land, knowledge of cattle farm management, use of technology and access to funding, and government support. This researchaims to evaluate the development of the POvillage breeding centerbased on internal and external factors. The research methodology employed involved conducting surveys, interviews, and documentation of cattle farmers, livestock group leaders, and Bojonegoro livestock department officials as sources of information. The method used in this study was purposive sampling. Descriptive quantitative and SWOT analyseswere carefully applied to the available data. The internal factor analysis yielded a total value of 1.03 on the positive X-axis, while the external factor had a value of 0.15 on the positive Y-axis. As a result, the SWOT analysis shows the development ofa PO village breeding centerin quadrant I, which indicated that the program for developinga village breeding centerwas on the right track (aggressive) by continuously implementing growth strategies. Developing the source area for PO cattle has excellent potential to enhance the productivity and quality of PO cattle produced. The development strategy of PO cattle village breeding centershould focus on the potential strength aspect of the capacity of local regions and farmers' support.

Trajectory Generation Considering Non-Holonomic Constraints for an Indoor Quadrotor

Nowadays the use of quadrotors is extremely extended in different recreational, industrial and research environments, for that reason having a way to generate motion following a predetermined position without losing the degrees of freedom of the quadrotor is an interesting idea. In the present work a model of a quadrotor with cross configuration is obtained, analytically by the Euler-Lagrange method, and non-holonomic constraints are imposed through a vector that gives the direction to follow in every movement it performs. A Twisting control is used to generate the point-to-point trajectory that the quadrotor should follow, in particular for this work, pointing to the positive x-axis of the quadrotor.

Oil droplet migration in the coupling of electric field and nano-confined shearing flow field: A molecular dynamics study

Electrocoagulation (EC) has become one of the main oily wastewater treatment method due to its low cost, high efficiency, and deep purification capability. In this study, the nano-oil droplet migration and deformation behaviors at different Reynolds numbers (Re), electrocapillary numbers (CaE), component types and SPAN (span-80) concentrations were investigated by molecular dynamics (MD) simulations. The weak interactions between SPAN&SiO2 (silicon dioxide) and ASP (asphaltene) molecules were mainly electrostatic interactions. The tendencies of oil droplet moving along the negative and positive x-axis were enhanced with respectively increasing CaE and Re, and the electric force (FE) was approximately equal to the shear force (FS) at CaE = 152.59 Re. The shearing flow field dominantly affected the tilt angle (θ), while the electric field mainly influenced the deformation ratio (D). ASP molecules were susceptible to FE, while RES (Resin) &HEX (n-hexane) molecules were susceptible to FS. In addition, the presence of both SPAN and SiO2 molecules can improve the oil droplet stability. The results can potentially provide theoretical guidance for the optimization of EC device.

Flow and heat transfer profiles in a heat exchanger tube equipped with X-V baffles (XVB): A numerical analysis

Simulations of laminar air flow and thermal configurations through a heat exchanger tube (HXT) equipped with X-V baffles (XVB) are performed. The Reynolds number is between 100 – 2000. The current numerical problem is solved by a numerical method (the finite volume analysis). Effects of the XVB sizes, the XVB distances and the flow directions on the flow and thermal profiles are discussed. The XVB size (b/D) is set between 0.05 – 0.20 and the XVB distance (P/D) is set to 1, 1.5 and 2. X-axis is the flow axis. The positive and negative x-axis are investigated. Two baffle configurations (Type I and II) are compared. The streamlines, vortex flows, temperature profiles and Nusselt number profiles in the HXT installed with these two XVB configurations (Type I and II) are described. The variations for the friction factor ratio (f/f0), Nusselt number ratio (Nu/Nu0) and thermal enhancement factor (TEF) within the HXT equipped with the XVB are presented. In addition, the TEF of 4.07 is found to be the best value for the present investigation.

저 채도 색 자극의 색상을 조사하기 위한 정신물리학 실험 방법 제안

The psychophysical experimental methods were investigated to find an effective method for measuring color perception for low chroma color. Hue of the display stimuli was measured by two psychophysical experiments. One is the forced-choice experiment. The participants classified the hue of the stimulus as either yellow or blue and red or green. The proportion from the repeated responses was plotted on the chromaticity diagram with two hue axis. The angle from the positive x-axis to the point induced from the hue proportion represents the hue angle. The hue angle was converted to the 400-hue quadrature scale to express the hue as the percentage of two neighboring unique hues. The other experimental method is the magnitude estimation. The participants judged the hue of the stimulus as a number. As the result, the participants evaluated the color of the stimulus easily with the forced-choice method. In addition, the standard deviation between participants was small in the forced-choice experiment. It means that the forced-choice method is reliable. Therefore, this study expects to use the forced choice method to measure hue of low chroma color.

Impact of Discrete Fracture Characteristics on Longwall Top Coal Stability

Discrete fractures may exist in thick coal seam and significantly impact the top coal stability in the Longwall Top Coal Caving method (LTCC) both ahead of shield support (top coal fall) and behind shield support (top coal caving). The top coal stability in such conditions is not well understood in the literature and has been studied from either fall or caving behaviour. In this paper, a discontinuum-based numerical program is used to study longwall top coal stability when discrete fractures exist in coal seam and vary in characteristics (i.e., orientation, density, stiffness, strength, and intersecting fractures). The study demonstrates that the existence of discrete fractures decreases the top coal stability ahead of shield support, particularly in initial face extraction. The parametric study finds that when the fracture orientation makes an angle of 90 degrees to the positive x-axis, it has the least impact on top coal fall. When the fractures plunge into the mined-out area, they facilitate top coal caving and vice versa when they plunge into the unmined area. The study reveals that the fracture density is directly proportional to top coal fall and top coal caving. Meanwhile, the fracture stiffness and strength are inversely proportional to both top coal fall and caving. The study also demonstrates the important role of coal seam characteristics (strength, elastic modulus, and depth) in top coal fall. The findings from this paper can assist engineers in improving panel geometry design and roof control for efficient underground mining when discrete fractures exist and vary in a coal seam.

A standard reference frame and geometry for nucleosomes.

The nucleosome is often described as a histone-DNA complex containing eight histones and 145-147 base pairs of DNA. The reality is more complex. Here we evaluate approximately 500 nucleosomes from the Research Collaboratory for Structural Biology with the goal of establishing a reference frame and standard geometry for describing the internal structure of mono-nucleosomes and the stacking of nucleosomes in arrays and clusters. Our reference frame places the center of mass of the nucleosome's octameric core at the origin. The positive x-axis aligns with the symmetry axis of the nucleosome and passes through the central base pair or base pair step associated with the octamer. The z-axis is defined by fitting a regular helix (constant pitch and radius) to the nucleosome. The positive direction is determined by the choice of reading strand. Two methods for defining this helix are explored. One fits a helix to the center line of the DNA, which is itself determined according to a standard reference geometry for DNA base pairs. The other fits a helix to the centers of mass obtained from the histones. The z-axes, so defined, are slightly askew. Over 100 nucleosomes are used to define a standard reference geometry for the histones and for super helices with 145, 146 and 147 base pairs. In all structures, the cumulative sum of Rise, Twist and arclength are linear functions of base pair index with R2 values in excess of 0.999. The standard geometry supports a rigorous definition of entry-exit angle and identification of structural anomalies. Select examples demonstrate how generalizations of the inter and intra base pair parameters can be utilized to analyze the internal structure of mono-nucleosomes, their stacking in arrays and clusters, and the ab initio assembly of atomic and coarse-grained structures.

Gaseous slip flow in a porous two-dimensional rectangular microchannel subjected to inclined magnetic field

In this study, two-dimensional, steady, laminar, and compressible gaseous flow of Newtonian fluid in a rectangular porous microchannel affected by an electromagnetic field, and under local thermal equilibrium condition was analytically investigated in the slip flow region (0.001<Kn < 0.1). The porous microchannel is entirely affected by uniform inclined magnetic field with an angle α from the positive x-axis, the range of this angle is 0 ≤ α ≤ 90°. Also, the porous microchannel effected by uniform electric field which points in the positive z-direction. Thermophysical properties of the fluid were assumed to be constant. The normalized governing equations were asymptotically solved and expressions of the flow velocity components, the pressure, and the temperature were provided using first-order velocity slip and temperature jump boundary conditions. The effects of various parameters on the flow were studied, such as Darcy number, the porosity, the thermal conductivity ratio, the electrical conductivity ratio, Hartmann number, Knudsen number, the electric field to magnetic field ratio (0 ≤ K ≤ 1), and the magnetic field inclination angle. It was found that increasing the permeability of the porous medium increases the flow velocity but decreases its temperature. Further, the results reveal that applying a stronger magnetic field in absence of electric field decreases the flow velocity but increases its temperature. On the other hand, the stronger the electric field, the higher the flow velocity and its temperature. Also, as the magnetic field inclination angle increases the flow velocity decreases. The effects of Darcy number and the electrical conductivity ratio on the heat flux were studied as well. A comparison of the analytical solutions with the numerical results were presented as a validation for this study. The comparison showed that the analytical results were in good agreement with the numerical results.

Enhancing drying efficiency and quality of seed-used pumpkin using ultrasound, freeze-thawing and blanching pretreatments

Effects of blanching (BL), ultrasound (US) and freeze-thawing (FT) pretreatments prior to far-infrared drying (FIRD) on drying characteristics, water distribution, and quality parameters of seed-used pumpkin (SUP) slices were investigated in this study. US, BL and FT pretreatments significantly accelerated drying rate due to the destruction of cell structure. Modified Page model was the fittest model for predicting the FIRD process. Low field nuclear magnetic resonance (LF-NMR) results revealed that T2 distribution curves of all pretreated samples moved rapidly to the positive x-axis direction, indicating an increase in the rate of water migration. The color of US-FIRD was closer to fresh SUP. BL-FIRD exhibited the highest free polyphenols content (241.28 ± 1.11 mg GAE/100 g DW) and total carotenoids content (129.69 ± 2.49 μg/ g DW), increasing by 45% and 34% respectively compared to the untreated sample.

Bearing Characteristics of Tripod Bucket Jacket Foundation for Offshore Wind Turbines in Sand under Monotonic Loads

Tripod bucket jacket foundation is an alternative foundation solution for deep-sea wind farms. This paper analyzes and compares the bearing characteristics of two tripod bucket jacket foundations with different height-diameter ratios, the tripod suction pile jacket foundation (TSPJF) and tripod bucket jacket foundation (TBJF), under different monotonic loads. The bearing modes of the two foundations under the vertical loads are different. The ultimate vertical load is mainly borne by the inside frictional resistance for the TSPJF, while it is mainly borne by the lid resistance for the TBJF. The foundations will take place translation and rotation under horizontal load. Under the positive x-axis loading, the vertical resistance of the TSPJF and TBJF is mainly composed of the soil resistance on the 1# bucket lid, the inside and outside frictional resistance. Under the negative x-axis loading condition, the vertical resistance is mainly composed of the inside and outside frictional resistance of buckets. The ultimate moment capacities of the TSPJF and TBJF in loading of the single bucket in compression is significantly larger than that in loading of the single bucket in tension. The failure mode of the TSPJF and TBJF in loading of the single bucket in tension is the pull-out failure of the bucket in tension.

Fault analysis of spur gear using XFEM

Spur gears are the most common and simplest in the geometric visualization, and are used to transmit motion and torque from the engine to the desired locations at different transmission ratios. Since the gears work in high loading conditions over a long period, the study of the gear faults due to the high stresses becomes important. In this study, the stresses generated at the root of the gear teeth due to bending is determined using finite element method (FEM) and validated analytically using Lewis theory. Further a detailed crack propagation analysis has been conducted with two intermediate backup ratios of 0.8 and 1.5 and allowing the initial crack length to vary as 0.125, 0.4, 0.7 and 1 mm and check the behavior of the crack propagation paths in static as well as dynamic loading conditions. Also the crack propagation path of the initial crack is observed at the orientations of 180° and 225° from the positive x-axis. The analysis shows that as the initial crack length increases there is increase in the stresses been generated. Further for both backup ratios of 0.8 and 1.5 it has been observed that the crack propagation paths shows variation as the initial crack length increases for both static and dynamic loadings and causes a shift from propagating through the rim to propagation into the width of the rim and showing vertical as well as horizontal propagation in higher initial crack lengths.

Perancangan Model Stacker Crane Flexible Manufacturing System untuk Pembelajaran di Institusi Pendidikan

Flexible Manufacturing System (FMS) is one of the modern production systems that support the implementation of Industry 4.0. An educational institution plans to build an FMS model for learning the modern production systems. The FMS is a manufacturing system consisting of a set of automatic workstations connected to a material handling system where all activities are controlled by a computer system. The material handling system consists of a material storage system and a transportation system, one example of a transportation system is the stacker crane. In this research, the stacker crane model has been built which consists of three main components, which are the bottom frame, the mast, and the carriage. This component is equipped with stepper motors, leadscrews that are controlled by the micro controller and an application on Android. The stacker crane model is tested to retrieve and deliver the stereofoam material model to the destination which is controlled by the user using an application on Android. The characteristics of the stacker crane model can move the workpiece with a maximum error of 2 mm in the positive x-axis direction, 2 mm in the negative x-axis movement, up to 2 mm positive y-axis, downward at negative y-axis direction 2 mm.

Effects of MHD and porosity on entropy generation in two incompressible Newtonian fluids over a thin needle in a parallel free stream

This article is devoted to studying Magnetohydrodynamic (MHD)'s combined effect and porosity on the entropy generation in two incompressible Newtonian fluids over a thin needle moving in a parallel stream. Two Newtonian fluids (air and water) are taken into consideration in this study. The viscous dissipation term is involved in the energy equation. The assumption is that the free stream velocity is in the direction of the positive x-axis—(axial direction). The thin needle moves in the same or opposite direction of free stream velocity. The reduced similar governing equations are solved numerically with the help of shooting and the fourth-order Runge–Kutta method. The expressions for dimensionless volumetric entropy generation rate and Bejan number are obtained through using similarity transformations. The effects of the magnetic parameter, porosity parameter, Eckert number, Bejan number, irreversibility parameter, Nusselt number, and skin friction are discussed graphically in detail for and taken as Newtonian fluids. The results are compared with published work and are found in excellent agreement.

Adaptive Boundary Observer Design for coupled ODEs-Hyperbolic PDEs systems

We consider the state estimation of ηξ hyperbolic PDEs coupled with ηX ordinary differential equations at the boundary. The hyperbolic system is linear and propagates in the positive x-axis direction. The ODE system is linear time varying (LTV) and includes a set of ηθ unknown constant parameters, which are to be estimated simultaneously with the PDE and the ODE states using boundary sensing. We design a Luenberger state observer, and our method is mainly based on the decoupling of the PDE estimation error states from that of the ODEs via swapping design. We then derive the observer gains through the Lyapunov analysis of the decoupled system. Furthermore, we give sufficient conditions of the exponential convergence of the adaptive observer through differential Lyapunov inequalities (DLIs) and we illustrate the theoretical results by numerical simulations.

Development of static solar panel equipped by an active reflector based on LDR sensors

Solar panels are a very effective source of renewable energy in Indonesia. To increase the output power of solar panels, especially on the static solar panels, a reflector is required as an additional device. This paper describes development of a static solar panel equipped with an active reflector. Five LDR sensors are mounted on the top of the reflector, to detect the highest solar intensity. Meanwhile, a DC motor as a reflector drive system is mounted on the bottom of the reflector. The tilt angle of the solar panel is 450 to the negative x-axis and the reflector is 750 to the positive x-axis. The reflector will move in a semi-circular path, following the direction of the highest solar intensity detected by the LDR sensor. Three different reflectors used to optimize the output power, there are stainless steel, aluminium foil, and mirror. Solar panel with mirror reflector produces the largest output power compared to other reflectors. The output power of this device increases 1.6 times to the solar panels without reflector.

Wave transport in fractional Schrodinger equations

In this paper, we have investigated the localization of an input spatial soliton as it propagates through a system where can be described by a fractional Schrodinger equation. In order to solve the Schrodinger equation, we have used a split-step Fourier method. We have also precisely presented the algorithm. We have found that by increasing the Levy index α the wave localization increases while the dispersion of the soliton decreases. Also, by increasing the parameter α, the amplitude of the oscillations decreases and the wave becomes more localized. By using the fractional parameter α, both peak intensity and position of the peak intensity can be tuned along the propagation distance. Finally, by decreasing the fractional parameter α the initial beam undergoes asymmetric diffraction with the position of the peak intensity moving toward positive x-axis and the symmetry of the input beam envelop breaks.

Natural convection in a cavity filled with porous medium under the effect of a partial magnetic field

Natural convection flow in presence of partially applied magnetic field in a porous medium is investigated in this study. Partial magnetic field is applied horizontally in the direction of positive x-axis, and vertical walls of unit square cavity are differentially heated. Fluid flow in the porous medium is modelled by Brinkman–Forchheimer-extended Darcy equation of motion. Pseudo spectral method based on polyharmonic spline radial basis function f=r7 is numerically performed for discretization of space derivatives and backward Euler method is carried out for time derivatives in governing dimensionless equations. The variation of the length of the partial magnetic field, Hartmann number, Rayleigh number, Darcy number and the location of the center of the partial magnetic field is presented in terms of streamlines, isotherms and vorticity contours. Central vortex in streamlines is pushed as the length of partial magnetic field increases in case of a top centered applied partial magnetic field. Convective heat transfer is suppressed if middle centered magnetic field is applied partially. Partial magnetic field may control fluid flow and heat transfer at required parts of the cavity.

A Stefan problem with variable thermal coefficients and moving phase change material

This article describes a one-phase Stefan problem in a semi-infinite domain that involves temperature-dependent thermal coefficients and moving phase change material with a speed in the direction of the positive x-axis. The convective boundary condition at a fixed boundary is also considered in the problem. An approximate approach to the problem is discussed to solve the problem with the aid of spectral tau method. The existence and uniqueness of the analytical solution to the problem are also established for a particular case, and the obtained approximate solution is compared with this analytical solution which shows that the approximate results are sufficiently accurate. The impact of a few parameters on the moving interface is also analysed.