Direction Of Y-axis Research Articles

Design and Structure Analysis of a CNC Laser Engraver Machine

This study aims to design a CNC machine to perform the laser engraving process (called the CNC Laser Engraver Machine). The design stage starts from the laser module unit as an input at the design stage of the 3-Axis CNC Machine to drive the laser. The main geometry of the machine is designed referred to the laser position i.e. workspace and laser height with respect to the engraving table. Then the geometry of the Z-Axis unidirectional laser drive unit is determined to assist when adjusting the laser height of the engraving table. Then the geometry of the laser drive unit in the direction of X-Axis and Y-Axis is designed to move on the engraving area, and then the geometry of the engraving table is designed. After the design is complete, the design is validated by analyzing the structure of the machine based on the conditions and workload of the machine to obtain the appropriate dimensions and materials. The design and structure analysis of the CNC Laser Engraver Machine is carried out by using the CAD software. The design results of the CNC Laser Engraver Machine consist of 5 units i.e. Laser Engraver Module Unit, Z-Axis Unit, X-Axis Unit, Y-Axis Unit and Engraving Table Unit which are mounted with a bolt system. This CNC Laser Engraver machine designed has a workspace of 310 mm x 390 mm in the X-Y plane with the laser height in the Z-Axis direction can be adjusted 10 mm to 60 mm above the engraving table. The total dimensions of this CNC Laser Engraver Machine are 585 mm x 533 mm x 350 mm with a total weight about 22 kg.

Numerical study of drug delivery through the 3D modeling of aortic arch in presence of a magnetic field.

Magnetic drug delivery known as smart technique in medicine is basically according to combining the drug inside capsules with the magnetic property or attaching the drug with magnetic surfaces at the micro- and nanoscale. In the present study, magnetic drug delivery in the aortic artery has been investigated. To approach the more realistic problem conditions of blood flow rheology, the effect of parameters such as non-Newtonian viscosity and oscillating input has been put into consideration. Also, the investigated geometrical parameters of arteries of the aortic arch have been chosen similar to the real size. The results indicate that an increase in the diameter of microparticles rises the efficiency of particles absorption. In addition, the influence of changing the direction of the wire carrying electricity and thus changing the direction of magnetic field on magnetic drug delivery has been examined in the geometry of the aortic arc and it is found that the highest particle absorption efficiency takes place in the case that the wire is parallel to the direction of y-axis. As an example, the results show that the rate of absorption efficiency for particles with 3µm dia is 26.83% and 19.39% when the wire generating magnetic field is parallel to the direction of y-axis and z-axis, respectively, and this value is 10.91% for the case without a magnetic field. The number of particles released from different part of the aortic arch also is affected by the direction of magnetic field. This value illustrates that the percentage of particles released from different states, is equal when the magnetic field is absent and the wire carrying electricity is parallel to y-axis and z-axis. However, the number of particles released from the 2 outputs of the left carotid and left subclavian is less than the other 2 states (i.e., the state when there is not a magnetic field, and the state when the electric current direction is parallel to the y-axis direction) for the state when the wire carrying current is parallel to the z-axis.

Heading Estimation for Multimode Pedestrian Dead Reckoning

The flexible carrying mode of smartphone brings challenge for Pedestrian Dead Reckoning (PDR) especially for heading estimation with build-in sensors. This paper focuses on POCKET mode and SWING mode and analyzes the correlation between smartphone's rotational motion and pedestrian's walking cycle states and walking direction. Based on the analysis, we propose to use the rotation vector sensor data of smartphone within one walking step to estimate the pedestrian's heading. For POCKET mode, heading is estimated by an improved rotational approach (IRA). A jitter detection algorithm is proposed to extract leg flexion interval. Stable walking direction without 180° ambiguity is obtained from the averaged rotation axis. For SWING mode, a single-point (SP) method is proposed. Heading is estimated from the direction of smartphone's y-axis when it is closest to the horizontal plane. The algorithms are validated with data collected by HUAWEI mate 10 smartphone. The RMS errors are less than 4.37° and 3.38° for POCKET and SWING mode respectively. Superior to previous heading estimation algorithms, our method can converge within one single walking step for both carrying modes without 180° ambiguity.

Effects of turbulent airflow from coal cutting on pollution characteristics of coal dust in fully-mechanized mining face: A case study

In order to investigate the influences of turbulent airflow disturbance from coal cutting on pollution characteristics of coal dust, the airflow migration and the coal dust dispersion was numerically simulated. For its research results, the local spray closure dedust technique was proposed and field test was carried out in the No. 905 fully-mechanized mining face of Jiangzhuang Coal Mine owned by Shandong Energy Zaozhuang Mining Group Co., Ltd. The results demonstrated that the turbulent airflow from coal cutting was quite stable, which can hardly be blown away by the ventilation airflow at a mean initial velocity of 1.3 m/s. There was an interaction between turbulent airflow from coal cutting and system ventilation airflow, resulting in further deviation of airflow. The velocity component along the positive direction of Y-axis was mainly responsible for the formation of deviated airflow and its migration from shearer haulage space to footway space. The regions with a mean deviated velocity component of over 0.3 m/s corresponded to heavy pollution regions in which the mean dust concentration exceeded 100 mg/m3. Compared with the original dust suppression measures, the local spray closure dedust technique can enhance the removal ratio of respiratory dust by an average of 26.7% and the coal dust concentration are less than 50 mg/m3 where the drum drivers and support moving worker operated.

Ultra-wide bandwidth polarization filter based on gold-coated photonic crystal fiber around the wavelength of 1.55 µm

A novel ultra-wide bandwidth photonic crystal fiber (PCF) polarization filter based on surface plasmon resonance (SPR) is proposed. The PCF has two large cladding air holes in the direction of y-axis that are selectively coated with gold films to create resonance. There are two small holes in the direction of x-axis, which provides high birefringence. The polarization characteristics of PCF are studied by finite element method (FEM). The numerical simulation results indicate that the loss of y-polarized core mode is 718.87 dB/cm, while the loss of x-polarized core mode is only 0.95 dB/cm at the resonant wavelength of 1.55 µm. The extinction ratio is better than 20 dB at the wavelength ranging from 1.43 to 1.79 µm, the corresponding bandwidth is 360 nm.

Effect of reagent vibrational excitation on reaction of H+CH+C++H2

The effect of reagent vibrational excitation on the stereodynamical properties of H(2S)+CH+(X1+)C+(2P)+H2(X1g+)reaction is investigated by quasi-classical trajectory method on a globally smooth ab initio potential surface of the 2A' state at a collision energy of 500 meV. The reaction probability and the reaction cross-section are also studied. In the calculation, the vibrational levels of the reactant molecules are taken as v = 0, 1, 3, 5 and j = 0, respectively, where v is the vibrational quantum number and j is the rotational quantum number. The calculation results show that the reaction probability reaches a maximum when v = 1, and then decreases with the vibrational quantum number increasing. The integral cross-section decreases sharply with the increase of vibrational quantum number. The potential distribution P(r), the dihedral angle distribution P(r), and the polarization-dependent generalized differential cross sections are calculated. P(r) represents the relation between the reagent relative velocity k and the product rotational angular momentum j'. P(r) describes the correlation of k-k'-j', in which k' is the product reagent relative velocity. The peak of P(r) is at r = 90 and symmetric with respect to 90, which shows that the product rotational angular momentum vector is strongly aligned along the direction perpendicular to the relative velocity direction. The peak of P(r) distribution becomes increasingly obvious with the increase of the rotational quantum number. The dihedral angle distribution P(r) tends to be asymmetric with respect to the k-k' scattering plane (or about r= 180), directly reflecting the strong polarization of the product angular momentum for the title reaction. Each curve has two evident peaks at about r = 90 and r = 270, but the two peak intensities are obviously different, which suggests that j' is not only aligned, but also strongly orientated along the Y-axis of the center-of-mass frame. The peak at r= 90 is apparently stronger than that at r = 270, which indicates that j' tends to be oriented along the positive direction of Y-axis. In order to validate more information, we also plot the angular momentum polarization in the forms of polar plots r and r. The distribution of P(r; r) is well consistent with the distribution P(r) and also the distribution P(r) of the products at different vibrational quantum states. In addition, the polarization-dependent differential cross section is quite sensitive to the reagent vibrational excitation. Based on the obtained results, we find that the observed excess of the methylidyne cation CH+ is closely related to the reactant of vibrational excitation in interstellar chemistry.

Transient Heat and Mass Transfer Flow through Salt Water in an Ocean by Inclined Angle

Abstract In the present computational study, the inclined angle effect of unsteady heat and mass transfer flow through salt water in an ocean was studied. The governing equations together with continuity, momentum, salinity and temperature were developed using the boundary layer approximation. Cartesian coordinate system was introduced to interpret the physical model where x-axis chosen along the direction of salt water flow and y-axis is inclined to x-axis. Two angle of inclination was considered such as 90° and 120°. The time dependent governing equations under the initial and boundary conditions were than transformed into the dimensionless form. A numerical solution approach so-called explicit finite difference method (EFDM) was employed to solve the obtained dimensionless equations. Different physical parameter was found in the model such as Prandtl number, Modified Prandtl number, Grashof number, Heat source parameter and Soret number. A stability and convergence analysis was developed in this study to describe the aspects of the finite difference scheme and this analysis is significant due to accuracy of the EFDM approach. The convergence criteria were observed to be in terms of dimensionless parameter as Pr ≥ 0.0128 and Ps ≥ 0.016. The distributions of the temperature and salinity profiles of salt water flow over different time steps were investigated for the effect of different dimensionless parameters and shown graphically.

Tight focusing properties of off-center Gaussian vortex beams

The properties of off-center Gaussian vortex beams focused by a high numerical aperture are investigated on the basis of vector Debye integral. A complex amplitude of off-center Gaussian vortex beams through a high numerical aperture objective is derived and numerical calculation is performed to analyze the intensity and phase distributions of the beams in the focal plane. It is shown that the intensity and phase distributions change significantly with the variation of off-axial distance; the intensity distribution in the focal plane is different in the direction of y-axis which is enhanced with the increase of off-axial distances; the sign of off-axial distance determines the direction in which the intensity is concentrated. On the other hand, different from the 1st order off-axial vortex beam, high-order off-axial vortex will split in the tightly focused field. Multiple phase singularities will appear and the number of singularities is equal to the topological charge of the original beam. Besides, the split singularities are symmetric, obviously. It is found that the splitting of high-order vortex is due to the tight focusing.

Dynamics for the reaction O+DCl→OD+Cl

With the quasi-classical trajectory method the stereodynamics of the O+DCl→OD+Cl reaction on the ground potential energy surface is investigated. The characteristic of calculated integral cross-section is consistent with that of the non-energy barrier reaction path on the potential energy surface, which implies that the title reaction is a typical exothermic reaction. The obtained differential reaction cross-section shows that the products tend to both forward and backward scattering, and the forward scattering is stronger than the backward one. So we can infer that the reaction follows the indirect reaction mechanism that has been verified by the randomly abstractive reaction trajectories. The distribution curves of P(θr) and 2(J'· K)> reflect that the degree of rotational alignment of the product OD first increases and then decreases with collision energy increasing. The product rotational angular momentum vector J' is aligned along the y-axis direction but is oriented along the positive direction of y-axis at higher collision energy. With the increase of the collision energy the rotation mechanism of the product molecules transits from the “in-plane” mechanism to the “out-of-plane” mechanism.

Effect of Reagent Vibrational Excitation on Product Rotational Polarization in Reactions Li + DF (v=0-3, j=0) → LiF(v', j') + D

A quasiclassical trajectory calculation is carried out to investigate the effect of reagent vibrational excitation on product rotational polarization in the reactions Li + DF (v=0-3, j=0) ---> LiF(v', j') + D. It is found that the reagent vibational excitation highly enhanced the product rotational alignment, however, the enhancement is not monotonically increasing with the gradual increase of the vibrational quantum number from v=0 to v=3. The product rotational orientation varies from the negative to positive direction ofyaxis with the increasing vibrational quantum number from v=0 to v=3.

Analysis on Sealing and Deformation of Exhaust Valve Housing of Marine Diesel Engine

MAN Diesels 6S50MC-C disel is a two-stroke marine diesel engine. Preload of the exhaust valve component is applied in four bolts. The preload of bolts can improve the fatigue strength of the exhaust component. In addition, the bolt pretension ensure the sealing in the maximum firing pressure. Using of simulation method, the displacement and deformation of exhaust valve component are analyzed when the maximum firing pressure and preload are applied. By analysis of the deformation of the exhaust valve housing under different preload force, the deformation of exhaust valve housing increase with the increaseing of preload. The maximum total deformation is 0.40mm in the preload of 720KN. The maximum deformation occurs in the region near the bolt in the side of exhaust gas outlet. The deformation in the direction of Y-axis of exhaust valve housing is along the Y-axis opposite direction when the preload is greater than 540KN. This indicates that the exhaust valve seal well. The sealing and deformation of the exhaust valve component meets the desgin requirement.

Quasi-Classical Trajectory Study of the Reaction N(4S) + H2 (v = 0, j = 0) → NH + H(2S) Stereo Dynamics Properties

Using a quasi-classical trajectory study method, the stereodynamics for N(4S) + H2 (v = 0, j = 0) → NH + H(2S) reaction have been investigated on an accurate NH2 potential energy surface (PES) reported by Poveda and Varandas [L. A. Poveda, A. J. C. Varandas, Phys. Chem. Chem. Phys. 7(2005)2867], in the collision energy range of 25–70 kcal mol−1. The four generalized polarization dependent differential cross-sections (PDDCSs) (2π/σ)(dσ00/dω t ), (2π/σ)(dσ20/dω t ), (2π/σ)(dσ22+/dω t ), (2π/σ)(dσ21−/dω t ) and the rotational-state distributions of product NH are calculated in the center-of-mass frame at three different collision energies. The distribution of the angle between k ′ and j′, P(θ r ), the distribution of the dihedral angle denoting k - k ′- j ′ correlation, P(φ r ), as well as the angular distribution of product rotational vectors in the form of polar plots P(θ r , φ r ) are discussed. The results indicate that the product rotational angular momentum j ′ is not only aligned, but also oriented along the negative direction of y-axis. The calculated results reveal that the stereo-dynamics properties of the title reactions are sensitive to the collision energy.

A QUASI-CLASSICAL TRAJECTORY STUDY ON STEREODYNAMICS OF THEF+HCl(v = 0, j = 0) →HF+ClREACTION

Quasiclassical trajectory (QCT) calculations for the title reaction are carried out by employing the recent developed accurate potential energy surface of the 12A′ ground state. Two angular distributions, P(θr) and P(ϕr), with θr, ϕrbeing the polar angles of the product angular momentum, and two commonly used polarization dependent differential cross sections, (2π/σ)(dσ00/dωt) and (2π/σ)(dσ20/dωt), with ωtbeing the polar coordinates of the product velocity, are generated in the center-of-mass frame. It was found that the product rotational angular momentum j′ is not only aligned, but also oriented along the negative direction of y-axis. We also investigated the product state distributions in the present work, and found that the vibrational and rotational state distributions are inverted. Influences of collision energies on the product polarization and state distributions are also shown and discussed.

Analysis of Electromagnetic Inverse Model of Resistance Spot Welding

Resistance spot welding (RSW) is an important welding process in modern industrial production, and the quality of welding nugget determines the strength of products to a large extent. Limited by the level of RSW quality monitor, however, RSW has rarely been applied to the fields with high welding quality requirements. Associated with the inversion theory, in this paper, an electromagnetic inverse model of RSW was established, and the analysis of influence factors, such as the layout of the probes, the discrete program and the regularization method, was implemented as well. The result shows that the layout of the probe and the regularization method has great influence on the model. When the probe is located at the y direction of x-axis or the x direction of y-axis and Conjugate Gradient method is selected, a much better outcome can be achieved.

Effects of Reagent Rotation on Stereodynamics Information of the Reaction O(1

Quasiclassical trajectory (QCT) method has been used to investigate stereodynamics information of the reaction <TEX>$O(^1D)+H_2{\rightarrow}\;OH$</TEX>+H on the DK (Dobbyn and Knowles) potential energy surface (PES) at a collision energy of 23.06 kcal/mol, with the initial quantum state of reactant <TEX>$H_2$</TEX> being set for v = 0 (vibration quantum number) and j = 0-5 (rotation quantum number). The PDDCSs (polarization dependent differential cross sections) and the distributions of P(<TEX>$\theta_r$</TEX>), P(<TEX>$\phi_r$</TEX>), P(<TEX>$\theta_r$</TEX>, <TEX>$\phi_r$</TEX>) have been presented in this work. The results demonstrate that the products are both forward and backward scattered. As j increases, the backward scattering becomes weaker while the forward scattering becomes slightly stronger. The distribution of P(<TEX>$\theta_r$</TEX>) indicates that the product rotational angular momentum j' tends to align along the direction perpendicular to the reagent relative velocity vector k, but this kind of product alignment is found to be rather insensitive to j. Furthermore, the distribution of P(<TEX>$\phi_r$</TEX>) indicates that the rotational angular momentum vector of the OH product is preferentially oriented along the positive direction of y-axis, and such product orientation becomes stronger with increasing j.

Chemical stereodynamics of the [formula omitted] reaction on the two lowest triplet electronic states

In this article, we apply the quasi-classical trajectory (QCT) method to study the reaction O ( 3 P ) + H 2 ( ν = 0 , j = 0 ) → OH + H on the 3A′ and 3A″ potential energy surfaces (PESs). Information of the vector correlations revealing the product alignment and orientation on the two different triplet PESs has been provided. The results of the calculations show that the products not only align strongly along the direction perpendicular to reagent initial relative vector k , but also orient along the direction of the negative y-axis, with stronger product polarizations being observed on the 3A″ PES at the collision energy smaller than 24 kcal/mol and on the 3A′ PES at the collision energy bigger than 24 kcal/mol. On both PESs, especially on the 3A″ PES, the products show preference for backward scattering which becomes weaker as collision energy increases.

Intensity Borrowing via Excitonic Couplings among Soret and Qy Transitions of Bacteriochlorophylls in the Pigment Aggregates of Chlorosomes, the Light-Harvesting Antennae of Green Sulfur Bacteria

Model calculations of linear dichroism (LD) and circular dichroism (CD) spectra were conducted for the chlorosomes of green sulfur bacteria, Chlorobium phaeobacteroides and Chlorobium tepidum, on the basis of the theory of delocalized exciton. The chlorosomes of Chl. phaeobacteroides and Chl. tepidum contain bacteriochlorophylls (BChls) e and c as the major light-harvesting pigments, respectively. The excitonic couplings among the Soret and Q(y) transitions were considered on the basis of the "rodlike" structural model for the pigment self-aggregates in a chlorosome. Trial simulations were conducted by assuming the B(x) and B(y) transition-dipole vectors to be parallel to the molecular x- and y-axes, respectively. The simulation at this stage could nicely reproduce the larger splitting of the Soret band and more significant enhancement of the Q(y) band upon formation of chlorosome in the BChl e-containing chlorosome than in the BChl c-containing one. Intensity borrowing was indicated to be the key mechanism inducing the enhancement of the Q(y) band in the BChl e-containing chlorosomes. However, the simulated LD and CD spectra in the Soret region showed qualitative disagreement from the observed ones. To resolve the deviations, the directions of the B(x) and B(y) transition-dipole vectors and the orientations of the molecular planes of BChls were adjusted in the next stage. The fine-tuning of these parameters resulted in a striking agreement between the observed and simulated CD and LD spectra over the whole spectral range studied. The best fit was obtained when the B(x) and B(y) transition-dipole vectors were assumed to be rotated 25 degrees clockwise from the molecular x- and y-axes and the molecular planes in the pigment aggregate were tilted 5 degrees from that assumed in the original model without alteration in the direction of the molecular y-axis. The calculated spectral profiles were affected little by the change in the curvatures of the rod surface, showing that the optical spectra of chlorosomes were determined essentially by the local pigment arrangement, but not by the higher-order structure, of the aggregate.

Theoretical Study on Stereodynamics of Reactions of N(2D)+H2 → NH+H and N(2D)+D2 → ND+D

The vector correlations between products and reagents for the title reactions have been calculated by the quasi-classical trajectory method at a collision energy of 21.32 kJ/mol on an accurate potential energy surface of Ho et al. (J. Chem. Phys. 119, 3063 (2003)). The peaks of the product angular distribution are found to be in both backward and forward directions for the two title reactions. The product rotational angular momentum is not only aligned, but also oriented along the negative direction of y-axis. These theoretical results are in good agreement with recent experimental findings for the two title reactions. The isotopic effect is also revealed and primarily attributed to the difference of the mass factor in the two title reactions.

Quasi-classical trajectory study of the N( 2D) + H 2 → NH + H and N( 2D) + D 2 → ND + D reactions: Vector correlation

The vector correlations between products and reagents for the title reactions are investigated by employing the quasi-classical trajectory (QCT) method. A collision energy of 3.8 kcal/mol and an accurate 1 2A″ state potential energy surface (PES) of [11] are used in calculations. The four generalized polarization-dependent differential cross-sections (PDDCSs) ( 2 π / σ ) ( d σ 00 / d ω t ) , ( 2 π / σ ) ( d σ 20 / d ω t ) , ( 2 π / σ ) ( d σ 22 + / d ω t ) , and ( 2 π / σ ) ( d σ 21 - / d ω t ) are calculated in the center-of-mass frame. The distribution of the angle between k and j ′, P( θ r ), the distribution of the dihedral angle denoting k – k ′– j ′ correlation, P( ϕ r ), as well as the angular distribution of product rotational vectors in the form of polar plots P( θ r , ϕ r ) are also calculated. The results indicate that the product rotational angular momentum j ′ is not only aligned, but also oriented along the negative direction of y-axis. The isotope effect is revealed and primarily attributed to the difference in mass factor between the two title reactions.

Effects of reagent vibration on stereodynamical information of the reaction S( 1D) + H 2( v = 0–3, j = 0) → SH + H

Quasiclassical trajectory (QCT) method has been used to investigate stereodynamics of the reaction S( 1D) + H 2 → SH + H on a globally smooth ab initio potential surface of the 1A′ state [10] at a collision energy of 23.06 kcal/mol, with the initial quantum state of reactant H 2 being set for v = 0–3 (vibration quantum number) and j = 0 (rotation quantum number). The PDDCSs (polarized dependent differential cross-sections) and the distributions of P( θ r), P( ϕ r), P ( θ r , ϕ r ) have been presented in this work. The results demonstrate that the products are both forward and backward scattered. As v increases, the backward scattering becomes weaker while the forward scattering becomes stronger. The distribution of P ( θ r ) indicates that the product rotational angular momentum j′ tends to align along the direction perpendicular to the reagent relative velocity vector k, but this kind of product alignment appears weaker when v changes from 0 to 1 and then becomes stronger with v increasing to 3. Furthermore, the distribution of P ( ϕ r ) indicates that the rotational angular momentum vector of the SH product is preferentially oriented along the positive direction of y-axis, and such product orientation becomes stronger with increasing the value of v.