Line Contour Research Articles

Full quantum calculations of the line shape for H2O perturbed by Ar at temperatures from 20 to 300 K.

This work theoretically studied the spectral line shape of H2O perturbed by Ar in the temperature range of 20-300K for the pure rotational lines below 360cm-1, as well as three lines (31, 2 ← 44, 1, 54, 2 ← 41, 3, and 73, 5 ← 60, 6) in the v2 band. In order to perform precise dynamical calculations at low collision energies, a full-dimensional long-range potential energy surface was constructed for the H2O-Ar system for the first time to correct the long range of our newly developed intermolecular potential energy surface. Subsequently, the six line-shape parameters (pressure-broadening and -shifting parameters, their speed dependencies, and the complex Dicke parameters) were determined from the generalized spectroscopic cross section by the full quantum time-independent close-coupling approach on this new potential energy surface. Our theoretical results are in good agreement with the available experimental observations. Furthermore, the influence of the speed-dependence and Dicke narrowing effects on the line contour was revealed by comparing the differences among the Hartmann-Tran, quadratic-speed-dependent Voigt, and Voigt profiles. The temperature dependence of each line-shape parameter was further parameterized using the triplet-power-law for three pure rotational 61, 6 ← 52, 3, 41, 4 ← 32, 1, and 31, 3 ← 22, 0 lines. These line-shape parameters will provide a comprehensive set of theoretical references for subsequent experimental measurements.

Detection of electrode misalignment and its effect on joint quality in resistance spot welding: a low-cost computer vision-based approach

Electrode misalignment in resistance spot welding can be caused by poor fitting or deformation of electrode with continuous usage. This leads to asymmetric weld nugget formation, porosity and expulsion. This paper presents a novel low-cost real-time inspection system for angular misalignment using an image processing approach. The proposed solution can effectively segment the electrode tips even from the image captured at noisy industrial background such as automotive assembly line, by using a regional convolutional neural network based object identification method. The trained model has a mean average precision and recall of 99.01% and 96.6%, respectively. A series of image processing tools and mathematical operations were used to identify the edge line contours of electrode tips accurately from the detection mask, and determine the angular misalignment with a maximum deviation of less than 0.06°. Experimental results showed that the weld nuggets exhibited porosity, shrinkage voids, and cracks when performed under angular misalignment conditions.

Vagueness and volume: Testing the perception of depth in images with linear, sharp, or blurred contours.

In European painting, a transition took place where artists started to consciously introduce blurred or soft contours in their works. There may have been several reasons for this. One suggestion in art historical literature is that this may have been done to create a stronger sense of volume in the depicted figuresor objects. Here we describe four experiments in which we tried to test whether soft or blurred contours do indeed enhance a sense volume or depth. In the first three experiments, we found that, for both paintings and abstract shapes, three dimensionality was actually decreased instead of increased for blurred (and line) contours, in comparison with sharp contours. In the last experiment, we controlled for the position of the blur (on the lit or dark side) and found that blur on the lit side evoked a stronger impression of three dimensionality. Overall, the experiments robustly show that an art historical conjecture that a blurred contour increases three dimensionality is not granted. Because the blurred contours can be found in many established art works such as from Leonardo and Vermeer, there must be other rationales behind this use than the creation of a stronger sense of volume or depth.

INVESTIGATION OF SOLVATION IN LITHIUM PERCHLORATE -PROPYLENE CARBONATE-DIMETHYL CARBONATE SYSTEM BY RAMAN SPECTROSCOPY

The difference of solvent properties can significantly affect the solvation phenomena in individual and, especially, in mixed solutions. In particular, it can be assumed that in mixed solvents, i.e. in systems with intermediate dielectric permittivity (mixtures of linear and cyclic carbonic acid esters), cations will bind molecules of linear esters more strongly and bind molecules of cyclic esters more weakly than it takes place in individual solvents. In the present work the Raman spectra of lithium perchlorate solvents in propylene carbonate (PC), dimethyl carbonate (DMC) and their mixture in a wide range of salt concentrations are studied. It is shown that the solvation effects of the cation are clearly traced in the region of symmetric ring vibrations (~690-730 cm-1) of propylene carbonate and in the region of deformation vibrations of CCA (~520 cm-1) of dimethyl carbonate. These effects are also evident in the mixed solvent. The so-called method of differential spectroscopy was used to judge the structural changes of mixed-solvent systems. It consisted in constructing spectra of lithium salt solutions in mixed solvents, additive sum of spectra of lithium salt solutions in PC and DMC, as well as their difference (differential spectra). The analysis of differential spectra allows us to conclude that in systems with mixed solvent there is a weakening of interaction of propylene carbonate molecules with ions, and there is a preferential solvation of cations and anions by dimethyl carbonate molecules. Also, unlike propylene carbonate, dimethyl carbonate solvates perchlorate ions, which follows from the line contour changes in the region of CH3-group vibrations (2970 cm-1) solvation of anions is also observed in the mixed solvent. For citation: Rabadanov K.Sh., Gafurov M.M., Akhmedov M.A., Rabadanova D.I., Magomedova A.G. Investigation of solvation in lithium perchlorate -propylene carbonate-dimethyl carbonate system by raman spectroscopy. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 5. P. 36-42. DOI: 10.6060/ivkkt.20246705.6967.

Multi-centre evaluation of variation in cumulative dose assessment in reirradiation scenarios

Background and PurposeSafe reirradiation relies on assessment of cumulative doses to organs at risk (OARs) across multiple treatments. Different clinical pathways can result in inconsistent estimates. Here, we quantified the consistency of cumulative dose to OARs across multi-centre clinical pathways. Material and MethodsWe provided DICOM planning CT, structures and doses for two reirradiation cases: head & neck (HN) and lung. Participants followed their standard pathway to assess the cumulative physical and EQD2 doses (with provided α/β values), and submitted DVH metrics and a description of their pathways. Participants could also submit physical dose distributions from Course 1 mapped onto the CT of Course 2 using their best available tools. To assess isolated impact of image registrations, a single observer accumulated each submitted spatially mapped physical dose for every participating centre. ResultsCumulative dose assessment was performed by 24 participants. Pathways included rigid (n = 15), or deformable (n = 5) image registration-based 3D dose summation, visual inspection of isodose line contours (n = 1), or summation of dose metrics extracted from each course (n = 3). Largest variations were observed in near-maximum cumulative doses (25.4 – 41.8 Gy for HN, 2.4 – 33.8 Gy for lung OARs), with lower variations in volume/dose metrics to large organs. A standardised process involving spatial mapping of the first course dose to the second course CT followed by summation improved consistency for most near-maximum dose metrics in both cases. ConclusionLarge variations highlight the uncertainty in reporting cumulative doses in reirradiation scenarios, with implications for outcome analysis and understanding of published doses. Using a standardised workflow potentially including spatially mapped doses improves consistency in determination of accumulated dose in reirradiation scenarios.

Распространение П-образного радиоимпульса в селективно усиливающей сред

General relations are obtained that govern the evolution of the leading edge of a signal propagating in a selectively amplifying medium. The propagation of a pulse with a rectangular envelope, the carrier frequency of which is close to the frequency of one of the spectral amplification lines of a selective (in frequency) amplifying medium, is considered. The time dependence of the envelope of the initially rectangular signal is studied for various values of the optical thickness of the substance layer for the Gaussian and Lorentzian contours of the spectral line. It is shown that in the case of a shift of the carrier frequency of the signal relative to the center of the spectral line, the interference of the primary and amplified signal can lead to very significant oscillations of the total signal in time.

A Comparative Analysis of UAV Photogrammetric Software Performance for Forest 3D Modeling: A Case Study Using AgiSoft Photoscan, PIX4DMapper, and DJI Terra.

Three-dimensional (3D) modeling of trees has many applications in various areas, such as forest and urban planning, forest health monitoring, and carbon sequestration, to name a few. Unmanned Aerial Vehicle (UAV) photogrammetry has recently emerged as a low cost, rapid, and accurate method for 3D modeling of urban and forest trees replacing the costly traditional methods such as plot measurements and surveying. There are numerous commercial and open-source software programs available, each processing UAV data differently to generate forest 3D modeling and photogrammetric products, including point clouds, Digital Surface Models (DSMs), Canopy Height Models (CHMs), and orthophotos in forest areas. The objective of this study is to compare the three widely-used commercial software packages, namely, AgiSoft Photoscan (Metashape) V 1.7.3, PIX4DMapper (Pix4D) V 4.4.12, and DJI Terra V 3.7.6 for processing UAV data over forest areas from three perspectives: point cloud density and reconstruction quality, computational time, DSM assessment for height accuracy (z) and ability of tree detection on DSM. Three datasets, captured by UAVs on the same day at three different flight altitudes, were used in this study. The first, second, and third datasets were collected at altitudes of 60 m, 100 m, and 120 m, respectively over a forested area in Tully, New York. While the first and third datasets were taken horizontally, the second dataset was taken 20 degrees off-nadir to investigate the impact of oblique images. Results show that Pix4D and AgiSoft generate 2.5 times denser point clouds than DJI Terra. However, reconstruction quality evaluation using the Iterative Closest Point method (ICP) shows DJI Terra has fewer gaps in the point cloud and performed better than AgiSoft and Pix4D in generating a point cloud of trees, power lines and poles despite producing a fewer number of points. In other words, the outperformance in key points detection and an improved matching algorithm are key factors in generating improved final products. The computational time comparison demonstrates that the processing time for AgiSoft and DJI Terra is roughly half that of Pix4D. Furthermore, DSM elevation profiles demonstrate that the estimated height variations between the three software range from 0.5 m to 2.5 m. DJI Terra's estimated heights are generally greater than those of AgiSoft and Pix4D. Furthermore, DJI Terra outperforms AgiSoft and Pix4D for modeling the height contour of trees, buildings, and power lines and poles, followed by AgiSoft and Pix4D. Finally, in terms of the ability of tree detection, DJI Terra outperforms AgiSoft and Pix4D in generating a comprehensive DSM as a result of fewer gaps in the point cloud. Consequently, it stands out as the preferred choice for tree detection applications. The results of this paper can help 3D model users to have confidence in the reliability of the generated 3D models by comprehending the accuracy of the employed software.

The Use of CNN Network in the Generation of Clear Line Contours of Thangka Art

Thangka has been a crucial aspect of Buddhism for thousands of years. It acts as a visualization of the myths and legends that shaped Buddhism and attracted many devotees to worship. Furthermore, Thangka also serves as a reflection of the cultural, political and social aspect of Tibetan society in history. However, the paintings, especially the outlines, became extremely fragile after years of harsh environments. I utilized Deep learning, specifically the Convolutional neural network (CNN) as the main method for processing data. After numerous training the training loss gradually approaches 0, which means that the model no longer needs additional training. Under the CNN network I used max pooling which discards trivial information, rectified linear (ReLU) activation function, residential Network (ResNet), and other methods in this research to achieve a clear outline of Thangka. Through episodes of convolution and ReLU function, the image generated becomes gradually more defined in layer 1. However, as the image undergoes continuous process, it gradually becomes more abstract. Thus, the best results could be found in layer 1. This study aims to use the results from the CNN network convolution to aid researchers studying Thangka by helping to distinguish the outlines of the image effectively.

Clinical value of ultrasonic indicators in predicting the outcome of caesarean scar pregnancy after pregnancy termination

BackgroundTo investigate the predictive value of ultrasound indicators in early pregnancy for the outcome of caesarean scar pregnancy (CSP) after pregnancy termination.MethodsThis study retrospectively analysed the ultrasound images of 98 CSP patients who underwent transabdominal ultrasound-guided hysteroscopic curettage during early pregnancy at Changsha Hospital for Maternal and Child Health Care between January 2017 and October 2021. Patients were equally divided into a case group and a control group. The case group included 49 CSP patients with postoperative complications, such as intraoperative blood loss ≥ 200 ml or retained products of conception (RPOC). The remaining 49 CSP patients, with similar age and gestational age and with good postoperative outcomes, such as intraoperative blood loss ≤ 50 ml and no RPOC, were included in the control group. CSP was classified into three types according to the location of the gestational sac (GS) relative to the uterine cavity line (UCL) and serosal contour. Differences in ultrasound indicators between the case and control group were compared.ResultsThere were significant differences between the case and control groups in the mean gestational sac diameter (MGSD), residual myometrium thickness (RMT) between the GS and the bladder, blood flow around the GS at the site of the previous caesarean incision, and types of CSP (P < 0.05). The rs of each ultrasound indicator were as follows: 0.258, -0.485, 0.369, 0.350. The optimal threshold for predicting good postoperative outcomes, such as intraoperative blood loss ≤ 50 ml and no RPOC, by receiver operating characteristic (ROC) curve analysis of the RMT was 2.3 mm.ConclusionOur findings show that the RMT, blood flow around the GS at the site of the previous caesarean incision, and types of CSP have a low correlation with postoperative complications, such as intraoperative blood loss ≥ 200 ml or RPOC, of early pregnancy termination in patients with CSP. To some extent, this study may be helpful for clinical prognostic prediction of patients with CSP and formulation of treatment strategies. Given the low correlation between these three indicators and postoperative complications, further studies are needed to identify indicators that can better reflect the postoperative outcomes of CSP patients.

Natural convective Power law fluid flow in a crown cavity with heated cylinder: Application to energy transfer

The present study investigates heat transfer characteristics of power law fluid flow and energy transfer in a crown cavity with adjustment of the heated cylinder. The flow distribution is generated by the response of the heated cylinder. Additionally, the enclosure is partially adiabatic and the influence of cold interfaces is also taken. This whole setup generates a partial differential system in its mathematical translation. The numerical simulation is performed for the mathematical formulation by adopting the Galerkin Finite element method. The obtained results are analyzed against pertinent parameters of interest and presented via line graphs and contour maps for better explanation. The findings indicate that the K.E (energy motion) and Nu (Nusselt number) are higher for shear thinning While K.E energy motion) and Nu (Nusselt number) are higher is minimum for shear thickening.

Methods and experiments for collecting information and constructing models of bottom-layer contours in paddy fields

To realize intelligent, accurate, and efficient operation of paddy field machinery that drive the paddy field bottom-layer below the tillage layer, the paddy field bottom-layer contours must be known. However, surface measurement systems cannot directly measure paddy field bottom-layer contours, making it difficult to collect and digitally model. In this study, an agricultural machine without a shock-absorbing suspension on the rear axle was used as an acquisition platform. Combined with a global navigation satellite system (GNSS) and attitude and heading reference system (AHRS) positional measurement technology, a 1/4 single-degree-of-freedom model of the vehicle body collected bottom-layer contour information of paddy fields. Based on the Delaunay triangulation principle, a digital model of the bottom-layer contour was established based on the collected bottom-layer contour point set. Subsequently, the ray method, used to extract specific triangles containing predicted points, and the point-plane intersection principle, used to estimate the elevation of arbitrary points in the whole area of bottom-layer, were used. Straight line contour acquisition on concrete road slope, contour acquisition on the bottom-layer surface of a paddy field, and elevation estimation of arbitrary points in the whole area were performed as verification tests. The results indicate that, in the x, y, and z axes, the average errors of the cement slope profile collection were 0.86, 0.68, and 0.55 cm, respectively, with standard errors of 0.99, 0.78, and 0.67 cm, respectively. Further, the average errors of the bottom-layer contour collection of the paddy field were 1.57, 0.91, and 1.25 cm, respectively, with standard errors of 1.87, 1.01, and 1.55 cm, respectively. The average error of elevation estimation at any point in the whole area was 1.25 cm with a standard error of 1.49 cm. The presented method can continuously and accurately acquire bottom-layer contour information, construct a digital model of the bottom-layer contour, accurately predict the location coordinates of any point within the field, and provide a reference for the walking environment of intelligent farming machines and measurement methods for the production of high-precision topographic maps.

Splitting ore from X-ray image based on improved robust concave-point algorithm.

Image segmentation is a key part of ore separation process based on X-ray images, and its segmentation result directly affects the accuracy of ore classification. In the field of ore production, the conventional segmentation method is difficult to meet the requirements of real-time, robustness and accuracy during ore segmentation process. In order to solve the above problems, this article proposes an ore segmentation method dealing with pseudo-dual-energy X-ray image which is composed of contour extraction module, concave point detection module and concave point matching module. In the contour extraction module, the image is firstly cut into two parts with high and low energy, then the adaptive threshold is used to obtain the ore binary image. After filtering and morphological operation, the image contour is obtained from the binary image. Concave point detection module uses vector to detect concave points on contour. As the main contribution of this article, the concave point matching module can remove the influence of boundary interference concave points by drawing the auxiliary line and judging the relative position of auxiliary line and ore contour. With the matching concave points connected, the whole ore segmentation is completed. In order to verify the effectiveness of this method, a comparative experiment was conducted between the proposed method and conventional segmentation method using X-ray images of antimony ore as data samples. The result of industrial experiment shows that the proposed intelligent segmentation method can remove the interference of pseudo concave points on the contour, achieve accuracy segmentation result, and satisfy the requirements of processing X-ray image of ore.

A Contour Line Group Simplification Method Based on Classified Terrain Features

Contour line group simplification methods can effectively preserve terrain features during map making and producing. This process involves two main steps, namely terrain feature line extraction and contour bend selection. The terrain feature line extraction includes two steps, that is, terrain feature point extraction and classification, and terrain feature line connection. However, to date, many similar studies have not considered the hierarchy of terrain features. Therefore, we proposed a group simplification method for contour lines based on classified terrain features and tested it on a study area with mainly positive landforms. In accordance with geomorphological theory, we divided valleys into either gradually descending or ordinary. Valley points were extracted based on the constrained Delaunay triangulation method and then classified into the two categories. Gradually descending and ordinary valley lines were then connected. The contour bends were grouped based on the valley lines extracted and then selected according to the geometric indicators of the bend group. The results have demonstrated that the valley lines extracted closely matched human perception in integrity and structure. Contour lines simplified by our method achieved effective reduction of map information and adequate retention of the main terrain structures, which are similar to those from manual simplification.

Experimental and numerical study of the effect of the channel curvature angle on inertial focusing in curvilinear microchannels

Passive cell separation methods have attracted great attention due to their superiority over the other methods stemming from their easy fabrication, precise manipulation, cost-effectiveness, sensitivity, and simplicity. The fluid inertia in these methods is the main factor that is affected by the channel design; thus, the channel design parameters should be chosen accordingly. Even though all channel design parameters are well addressed in inertial microfluidics, the curvature angle of the channel has not yet been extensively studied. In this study, three different curvilinear microchannels with curvature angles of 180°, 210°, and 270° were designed, keeping all other remaining parameters the same. The focusing ability of the fluorescent polystyrene microparticles with diameters of 1.1, 3.3, and 9.9 μm was investigated both experimentally and numerically to understand focusing efficiency affected by the curvature angle of the microchannel. The first set of experiments was to determine the effect of the channel curvature and indicated the favorable design as channel C, which showed focusing qualities of 0.85 and 0.92 for 9.9 μm particles at volumetric concentrations of 2% and 5%, respectively. The remaining set of experiments and CFD simulations were conducted to observe the interaction of 3.3 and 9.9 μm particles and reveal the distortion of the focusing line and particulate phase contours for 9.9 μm particles at the flow rates between 0.3 and 0.7 ml/min, which was further confirmed by enriched mixtures containing 1.1, 3.3, and 9.9 μm particles. The study showed that mixtures comprising low diameter particles could not satisfy the focusing criteria, which emphasized the importance of an appropriate particle size and concentration for a single focus line. On the other hand, it was shown that geometric features of the microchannel such as the hydraulic diameter and the curvature angle together with the particle size determine the focusing quality both experimentally and numerically. To sum up, the increment of the channel curvature angle is a determining factor for particle focusing, and a single focusing line was observed on the particles maintaining the focusing criteria even in many particle conditions. While the focusing quality of the particles was reduced by multi-particle interactions, they were proven to be separable achieving the appropriate concentration ratio.

Facial Identity And Facial Speech Processing In Developmental Prosopagnosia

Developmental prosopagnosia is the life-long impaired ability to recognize familiar faces. The neural basis of this condition remains a matter of investigation. Face processing networks are bilateral but have right hemisphere dominance, and the location of lesions in acquired prosopagnosia is in keeping with this. There may be a complementary contribution from left hemisphere regions to certain types of face processing, and prior reports suggest that this might involve processing faces depicted by line contours or facial speech patterns by lip reading. We performed two studies in seven subjects with developmental prosopagnosia. The first task tested participants’ ability to match faces across viewpoint changes, with either unaltered photographs or high contrast line-drawing-like images. The second task involved a series of lip-reading tests to examine ability to perceive facial speech patterns. Performance on these two tasks was compared to twenty-three age- and education-matched control subjects. Prosopagnosic subjects had normal performance with line-contour faces, but facial processing showed no improvement with the added information in unaltered photographs. In facial speech pattern tests developmental prosopagnosic subjects could detect, discriminate, and identify facial speech patterns, but compared to controls, there was reduced use of visual cues or anomalous audiovisual integration in the McGurk effect, with only one subject performing normally. We conclude that developmental prosopagnosia may have a broader range of face processing impairment beyond just identity recognition. There can be association with a subtle impairment in lip-reading, which has been associated more with left than right fusiform damage after acquired lesions.

Исследование влияния интерференции в кювете на поглощение газа, измеренное с использованием метода нестационарной ТГц спектроскопии

Cell is the important part of the terahertz (THz) spectrometer designed to study the chemical composition of multicomponent gas mixtures, since it is used for supporting the optimal pressure of the gaseous sample. However, the reflection of electromagnetic waves from the cell windows leads to standing-wave interference, which can distort the measured spectrum. Mathematical modeling of the impact of the interference on the measured spectrum was carried out in the paper. The cell was treated as a Fabry-Perot cavity with infinite flat dielectric mirrors. Diffraction of electromagnetic waves, as well as the frequency dependences of the source power and the detector sensitivity, was taken out of the scope of the considered model. The two effects of the interference were described. The interference not only determined the slow frequency dependence of the cell transmission spectrum, but also affected the profile of the gas absorption lines reconstructed from the cell spectrum in accordance with the Bouguer-Lambert-Beer law. Both the processing of the measured spectrum and the setup calibration required for accurate quantitative measurements could be complicated by the effects. However, methods of modulation and non-stationary spectroscopy enabled to eliminate the first effect, they were possibly ineffective to eliminate the second one. Presumably, the detected distortion of the contour of the absorption lines was caused by a shift in the interference pattern and, accordingly, a change in the reflection coefficient of the cell due to the anomalous dispersion of the sample. The correlation of the distortions with the derivatives of the transmission spectrum of the empty cell was revealed. The obtained results could be used to develop algorithms for calibrating the measuring setup and processing experimental data.

Particle image recognition in the measurement of workpiece cleanliness

Monitoring the cleaning degree of workpiece surface cleaning is a key step in high-end equipment manufacturing. The use of image recognition technology to identify the cleaning degree of workpiece surface can effectively improve the quality and efficiency of workpiece cleaning. In this paper, a particle image recognition technology based on opencv was proposed, which uses a series of methods such as grayscale, binarization, morphological processing, line contour detection, contour extraction to statistically calculate the number and average size of particles. So that the surface cleanliness of the workpiece can be determined. Judging the surface cleanliness classification according to the particle size and quantity is a precise quantitative cleaning method.

Thermal analysis of micropolar fluid flow driven by electroosmosis and peristalsis in microchannel

Thermo-micropolar fluids contain small conductive particles which would be useful for drug delivery and localized heating. Considering the importance of the special fluid model (micropolar fluids), a mathematical model is formulated to analyse the heat transfer in electroosmotic flow of thermo-micropolar fluid in curved microchannel. A curvilinear coordinate system is adopted to describe the curved microchannel which is propagated by peristaltic pumping and generate the pressure gradient in addition to electroosmotic force. Eringen’s micropolar theory is employed to introduce the conservation of mass, linear momentum, angular momentum, and energy to model the problem. Numerical solutions are computed for low zeta potential and low Reynolds number using Mathematica NDSolver. The effects of microchannel curvature, electrokinetic, zeta potential, micropolar parameter and viscosities (shear and vortex viscosities) ratio on velocity fields, pressure gradient, temperature, contour of stream lines, shear stress isotherms and heat transfer coefficient are examined to provide a parametric analysis. Numerical results reveal that the pressure has slight deviation with wall curvature however the pressure changes significantly with variation in coupling number and electric field. Further, the linear and angular velocities of the micropolar fluid could be controlled by the electrokinetic phenomena.

Numerical simulation for mixed convection in a parallelogram enclosure: Magnetohydrodynamic (MHD) and moving wall-undulation effects

The investigation of the interaction between the wall driven fluid stream and the partially heated barriers is a filed of great interest for the researchers. The present analysis aims to evaluate free and forced convection in a corrugated-wall parallelogram cavity. A Heated source is located at the bottom of enclosure and the upper boundary maintained the mixed convection in the enclosure. Flow dynamics and thermal profiles are established with regard to magnetic field. The non-linear partial differential equation obtained from the mathematical interpretation of such complex physical system are solved numerically using finite element method. The outcomes of the simulation towards flow controlling parameters (Richardsonnumber0<Ri≤100,Hartmannnumber0≤Ha≤100,amplitude0.02≤Am≤1.00,magneticfieldinclination0≤φ≤π2) are presented in line graphs and contour maps. It is observed that forced convection dominates at low value of Richardson number and free convection dominates at larger values of Richardson number. Further, the results indicate that increasing wall undulation Am the velocity profile enhances the Nusselt number also possess higher values at maximum Am. It is also reported that heat the transfer rate has maximum behavior at large Ha and φ=π2.

A volume-independent conformity index for stereotactic radiosurgery.

To develop a volume-independent conformity metric called the Gaussian Weighted Conformity Index (GWCI) to evaluate stereotactic radiosurgery/radiotherapy (SRS/SRT) plans for small brain tumors. A signed bi-directional local distance (BLD) between the prescription isodose line and the target contour is determined for each point along the tumor contour (positive distance represents under-coverage). A similarity score function (SF) is derived from Gaussian function, penalizing under- and over-coverage at each point by assigning standard deviations of the Gaussian function. Each point along the dose line contour is scored with this SF. The average of the similarity scores determines the GWCI. A total of 40 targets from 18 patients who received Gamma-Knife SRS/SRT treatments were analyzed to determine appropriate penalty criteria. The resulting GWCIs for test cases already deemed clinically acceptable are presented and compared to the same cases scored with the New Conformity Index to determine the influence of tumor volumes on the two conformity indices (CIs). A total of four penalty combinations were tested based on the signed BLDs from the 40 targets. A GWCI of 0.9 is proposed as a cutoff for plan acceptability. The GWCI exhibits no target volume dependency as designed. A limitation of current CIs, volume dependency, becomes apparent when applied to SRS/SRT plans. The GWCI appears to be a more robust index, which penalizes over- and under-coverage of tumors and is not skewed by the tumor volume.