Vertical Straight Line Research Articles

An Alternate Non Umbilical Entry Port for Laparoscopic Entry in Thin Patients

Study Objective To study the feasibility of a non umbilical first blind entry port in patients with BMI less than 18.5. Design Retrospective study assessing the laparoscopic entry in patients operated during the study period from January 2011 to December 2019. Setting Patients were operated under general anesthesia. Patients or Participants Selection criteria was patients of BMI less than 18. Out of the total 7398 patients in which laparoscopic entry was done by the left lateral port,398 patients met the selection criteria.70 thin patients had history of previous surgeries. Interventions In the study group veress needle and first primary port was introduced through a left lateral paraumbilical port about 10 cm lateral to the umbilicus. This point is located on a straight line drawn 2.5cm medial to the ASIS at the level of umbilicus. During veress needle and primary 5mm trocar entry the abdominal wall is not lifted up and veress needle insertion is done in one straight vertical line without changing the direction to 45 degree. Under vision of first 5mm telescope the 10mm port and then accessory ports are inserted. This port placement is aimed at avoiding the major vessel injury. 5 mm port also optimizes the 10mm telescope port entry as is needed in cases with large masses and cases with previous surgery. This port then continues as main ergonomic ipsilateral working port. Measurements and Main Results All 398 cases were entered safely without any major complication or conversion to laparotomy. First blind entry was well delineated due to good muscle tone in thin patients. No long term sequelae noted. Conclusion Left lateral paraumbilical port is a safe alternate first blind non - umbilical port in thin patients with advantage of avoiding major vascular injury and avoiding adhesions in previous surgery cases.

Optimal covering of the equidistant square grid network

Let G be a plane graph, and let S be the union of all edges and vertices of G, equipped with the standard Euclidean topology of the plane. A path between points x,y∈S is a minimal, with respect to inclusion, connected subset of S containing x and y (here x and y are not necessarily endpoints of an edge). The distance between points x,y∈S, denoted as d(x,y), is the length of a shortest path between x and y in S. An ℓ-covering of G is a finite set of points X⊆S such that for every point y∈S, there is a point x∈X, such that d(x,y)≤ℓ. The ℓ-covering number of G is the minimum size of an ℓ-covering of G. Let α(m,n) be the ℓ-covering number of the grid graph on mn vertices embedded in the plane so that the edges are either horizontal or vertical straight lines of length ℓ. In this note we prove that α(m,n)=mn−12 for mn>1.

Incidence of Straight, Sloped and Curved Midlines in Adult Humans

It has been traditionally documented and accepted that even though adult humans may have asymmetrical faces, a vertical straight facial midline line has always been used for aesthetics and functional dental rehabilitation. The standardly used landmarks for ascertaining the midline have been the glabella, the tip of the nose, the philtrum and the pogonion. In this study the pogonion has not been used because it is displaced in over 90% of individuals as per the Smylist® observation due to the mandibular rotation. First the horizontal lines were used to define the midline and then the midline plotted. This study has been conducted to ascertain the Smylist® tenet that all facial midlines are not necessarily straight. The tenet is that the midline can be straight, sloped to either side or curved to either side. A total of 100 subjects from Mumbai, India were photo documented in a straight face view in a standardized format and analysed for the type of midline using the Smylist® Aesthetic software. The results showed that the ratio of the three kinds of midlines were as 3.75 % for the straight midline, 55.55 % for the sloped midline and 40.7 % for the curved midline. It can be concluded that this study has shown that the incidence of the straight midline is only a small fraction in all the individuals in an Indian population which would be different from a European population.

Hydrodynamic Model for Operational Forecasting in Coastal Waters of Ghana

The provision of economic resources to countries at the shore of Gulf of Guinea is a very important effort that has helped West Africa to develop to some extent. Taking the study area as a system it will be important to know the dynamics that occur in it to help neighouring countries predict its physical and thermodynamics states at all times. Ghana is located in West Africa and it is bordered in the south by the Gulf of Guinea or Atlantic Ocean. The objective of this research is to characterize the hydrodynamic circulation of the Gulf of Guinea areas neighouring Ghana. A 3-Dimensional hydrodynamic model was implemented in the territorial waters of Ghana using the Modelo Hidrodinamico, MOHID model to represent the dynamics and study the complex circulation pattern of the sea. To achieve this in an affordable computational time, nested domain approach was used to implement the hydrodynamic model in both 2 and 3-Dimensional gridded levels. The first level is a barotropic model with only tide. The nested domains of the rest of the levels are baroclinic forced with atmospheric and oceanic elements. To quantify its accuracy, the model was validated and calibrated in three stages; first, the frequency of the water level, followed by the circulation pattern and last, analysing the nature and profiles of the atmospheric and oceanic elements. The implemented model showed good agreement with the measured water surface level in the domain with mean error values not exceeding 14.00% of the measured data and with correlation factors higher than 0.80. Also, the intensity and direction of velocity observed in the current data are well represented by the model at the water surface levels with mean errors lower than 20.00% of the measured data components. The profiles obtained for both the temperature and salinity at shore show completely a straight line for salinity and also a straight line which is slightly curved at the top for the temperature profile. The vertical straight line for the salinity profile shows that at the shore the waters are not stratified vertically or they are well mixed. The slight curve at the top of the temperature graph accounts for the mixing dynamics that occur close to land or the effect of heat flux at the surface. It can be concluded that the hydrodynamic model obtained by this study is the true reflection of the territorial waters of Ghana.

Defected waveguide structure designs and characteristics

AbstractThis article presented defected waveguide structure (DWS) designs and characteristics with microstrip‐fed circular monopole antenna for ultrawideband applications. Typically, waveguide is often designed and employed as antenna and filter application in its rigid dimension. The reconfigurable design toward the waveguide in terms of structural alteration with DWS was found less concerned among researchers although defected ground structure and defected microstrip structure have been applied widely. The motivation of this article was to propose the different DWS designs and characteristics in terms of the S‐parameters result. DWS in basic square geometry with different configurations of straight lines were introduced and compared with FR4 substrate waveguide. Simulated S‐parameters results were modeled in terms of equivalent circuit and measured for validation. For practical measurement, waveguide ports at both open‐ended surface of waveguide were replaced by the monopole antenna. For the modeled S‐parameters results, the square DWS design and square DWS with horizontal straight lines showed quite similar characteristics with higher S11 and lower S21 above frequency 9 GHz. Whereas square DWS with vertical straight lines and square DWS with both horizontal vertical straight lines showed higher S11 and lower S21 below frequency 3.5 GHz. Square DWS with vertical straight lines achieved the lowest S21 around −70 dB below 3.5 GHz and lower S21 around −50 dB at frequency 10.3 GHz. Thus, DWS is proposed for the future smart antenna technology as it can be further modified to meet the different requirements without changing the antenna configuration.

Heart to spine measurements to detect left atrial enlargement in dogs with mitral insufficiency

BackgroundRadiography is useful to determine left atrial (LA) size when echocardiography is not available. Recently, the authors have described Radiographic Left Atrial Dimension (RLAD) as a new radiographic measurement to assess LA size. The objective of this study was to assess the clinical usefulness of 2 new radiographic measurements to detect and quantify left atrial enlargement (LAE) compared to RLAD and using left atrium to aortic root (LA/Ao) ratio as gold standard. These new measurements, bronchus-to-spine (Br-Spine) and RLAD-to-spine (RLAD-Spine) may be more precise in cases were LA boundaries are not well defined. Fifty dogs, 25 with and 25 without LAE were recruited. Reference LA/Ao ratio was assessed by 2D echocardiography and LAE was considered if LA/Ao > 1.6. Br-spine was measured as a straight vertical line from the main stem bronchus to the ventral border of the vertebra situated immediately dorsal to the heart base. RLAD-Spine was measured from RLAD endpoint perpendicularly to spine. The correlation of RLAD, Br-Spine and RLAD-Spine methods with LA/Ao and their sensitivity and specificity for detecting LAE were calculated. Receiver Operating Characteristic (ROC) curves were used to estimate the optimal cut-off for each method.ResultsCorrelations between Br-Spine, RLAD-Spine, RLAD and LA/Ao ratio were − 0.66, − 0.76 and 0.89 respectively (P < 0.001). Sensitivity at the optimal cut-off values for detecting LAE were 32.0, 64.0 and 96.0%, respectively. Specificity was 96.0% in all cases.ConclusionBr-Spine and RLAD-Spine were less sensitive radiographic measurements than RLAD in detecting LAE in dogs. Both Br-Spine and RLAD-Spine may not be good alternatives to RLAD.

Analysis of random walks on a hexagonal lattice

Abstract We consider a discrete-time random walk on the nodes of an unbounded hexagonal lattice. We determine the probability generating functions, the transition probabilities and the relevant moments. The convergence of the stochastic process to a two-dimensional Brownian motion is also discussed. Furthermore, we obtain some results on its asymptotic behaviour making use of large deviation theory. Finally, we investigate the first-passage-time problem of the random walk through a vertical straight line. Under suitable symmetry assumptions, we are able to determine the first-passage-time probabilities in a closed form, which deserve interest in applied fields.

Blade/casing rubbing interactions in aircraft engines: Numerical benchmark and design guidelines based on NASA rotor 37

In order to improve the efficiency of aircraft engines, the reduction of clearances between blade tips and their surrounding casing is one avenue manufacturers consider to lower aerodynamic losses. This reduction increases the risk of blade tip/casing contact interactions under nominal operating conditions. Designers need tools to accurately predict subsequent nonlinear vibrations. Engineers and researchers have developed a variety of sophisticated numerical models to predict blades' responses. These models are related to distinct frameworks (time/frequency domain) and various solution algorithms (explicit/implicit time integration schemes, penalty/Lagrange multiplier contact treatment…) which calls for comparative analyses. However, published results are often limited for the sake of confidentiality thus preventing any detailed confrontation. While qualitative understanding can be gained from simplified academic models, full scale models are needed to predict complex interactions in a realistic manner. In this context, this paper proposes a benchmark featuring detailed simulations and analyses of a full 3D finite element model based on the open NASA rotor 37 compressor blade to facilitate reproducibility and collaboration across the research community. NASA rotor 37, a compressor stage widely used as a test case in aerodynamic simulations and validations, has the advantage of presenting a realistic blade geometry. The geometry of the blade is built from publicly available reports. The paper provides details on the geometry, the numerical model and the results to allow an easy use of this model across the fields of structural dynamics. Two contact scenarios are investigated: one with direct contact against the casing, and one with abradable material deposited on the casing to mitigate contact severity through wear. The nonlinear vibration response of the blade is simulated in the time domain. It is evidenced that the addition of the abradable material decreases the amplitude of vibration for most of the angular speeds investigated. However, new interactions appear for some angular speeds. The obtained results are consistent with previous simulations on industrial geometries. Based on works showing improved aerodynamic performances when the blade is tilted, a total of seven geometries are investigated: the reference blade, with a straight vertical stacking line similar to the original rotor 37, two forward-leaned blades, two backward-swept blades and two full forward chordwise swept blades. The sweep and lean variations are shown to have a dramatic impact on the vibration response: the backward sweep results in an increased blade's robustness to contact events and the full forward chordwise sweep in a reduced robustness, while the forward lean leads to a robustness similar to the reference blade.

Stability Analysis of Line Patterns of an Anisotropic Interaction Model

Motivated by the formation of fingerprint patterns we consider a class of interacting particle models with anisotropic, repulsive-attractive interaction forces whose orientations depend on an underlying tensor field. This class of models can be regarded as a generalization of a gradient flow of a nonlocal interaction potential which has a local repulsion and a long-range attraction structure. In addition, the underlying tensor field introduces an anisotropy leading to complex patterns which do not occur in isotropic models. Central to this pattern formation are straight line patterns. For a given spatially homogeneous tensor field, we show that there exists a preferred direction of straight lines, i.e.\ straight vertical lines can be stable for sufficiently many particles, while many other rotations of the straight lines are unstable steady states, both for a sufficiently large number of particles and in the continuum limit. For straight vertical lines we consider specific force coefficients for the stability analysis of steady states, show that stability can be achieved for exponentially decaying force coefficients for a sufficiently large number of particles and relate these results to the K\"ucken-Champod model for simulating fingerprint patterns. The mathematical analysis of the steady states is completed with numerical results.

Does the period table appear doubled? Two variants of division of elements into two subsets. Internal and secondary periodicity

Demarcation of elements for two subsets appears to be the most fundamental approach to their classification. If one draws a vertical straight line through the middle of each block of elements in the Periodic table, all the elements are divided into two subsets: “early” and “later”. For example, in the d-block, the early ones are Sc–Mn, and the late ones, respectively, are Fe–Zn. Later elements partially repeat the properties of the early ones, and this is defined as the internal periodicity. Another criterion for dividing the elements into two subsets is the evenness and oddness of the sum of n + l, where n is the principal quantum number, and l is the orbital quantum number for the outer electron subshells. Properties of the odd elements (for example, B–Ne, Ga–Kr, Tl–Rn in the p-block) are closer to each other than to properties of even elements (Al–Ar, In–Xe), and vice versa. This regularity is manifested as the secondary periodicity. The history of concepts, which considered the existence of subsets as well as of inner and secondary periodicities, is discussed. The features of the electronic structure, which underlie the existence of subsets, are considered. The existence of subsets was depicted earlier by dividing the periodic table into two tables or by applying a mirror-symmetric table. Small changes are proposed in the conventional Periodic table, allowing to reflect the existence of the considered subsets.

Characterization of time series via Rényi complexity–entropy curves

One of the most useful tools for distinguishing between chaotic and stochastic time series is the so-called complexity–entropy causality plane. This diagram involves two complexity measures: the Shannon entropy and the statistical complexity. Recently, this idea has been generalized by considering the Tsallis monoparametric generalization of the Shannon entropy, yielding complexity–entropy curves. These curves have proven to enhance the discrimination among different time series related to stochastic and chaotic processes of numerical and experimental nature. Here we further explore these complexity–entropy curves in the context of the Rényi entropy, which is another monoparametric generalization of the Shannon entropy. By combining the Rényi entropy with the proper generalization of the statistical complexity, we associate a parametric curve (the Rényi complexity–entropy curve) with a given time series. We explore this approach in a series of numerical and experimental applications, demonstrating the usefulness of this new technique for time series analysis. We show that the Rényi complexity–entropy curves enable the differentiation among time series of chaotic, stochastic, and periodic nature. In particular, time series of stochastic nature are associated with curves displaying positive curvature in a neighborhood of their initial points, whereas curves related to chaotic phenomena have a negative curvature; finally, periodic time series are represented by vertical straight lines.

Improvement of the technological process of sowing by stubble seeders

The basis of the seeding machine fleet is the stubble seeders SZS-2.1, SKP-2.1. A disadvantage of such seeders is the irrational use of the area of feeding due to the uneven distribution of the seed. Improvement of the technological process of sowing is possible by installing seed spreaders on the paw coulters. A scheme of a paw coulter with a passive seed distributor is proposed, each side of which consists of two planes installed at different angles. The calculation scheme and mathematical model allowed to study the process of seed distribution, to reveal the influence of constructive parameters of the coulter and the two-plane distributor on the trajectory of the particle, to determine the rational parameters of the distributor. In Mathcad, a program has been developed that simulates the trajectory of the particle movement along the coulter stand and in the limited under-paw space, which allowed the calculation of the seed distribution process with a coulter with a two-plane distributor. This program allows you to determine the geometric and kinematic parameters of the grain flight reflected from the distributor and the ceiling surface of the opener (trajectory, flight range, direction of the velocity vector when falling to the ground, etc.) when varying the inclination angles of the reflector planes, the incidence of the particle and its physical and mechanical properties. The calculation includes determining the flight parameters of the grain along the vertical straight line in the first stage of the flight, along the “ballistic” curve after each reflection. The results of the calculation are given in the form of a graphical representation of particle trajectories and tables with numerical values of the coordinates of the trajectory and the range of the rebound. To confirm the reliability of the results of theoretical studies and to determine the uniformity of sowing, laboratory tests of paw coulters with two-plane seed spreaders were carried out. The design parameters of two-plane distributors are determined, which ensure the maximum uniformity in the distribution of seeds along the width of the coulters of stubble seeders. Equipping the paw coulters with two-plane spreaders provides seeding with higher quality indices on uniformity and will ensure an increase in the productivity of agricultural crops.

Bifurcation of Limit Cycles from a Class of Piecewise Smooth Systems with Two Vertical Straight Lines of Singularity

Perturbing the following systems [Formula: see text] having a linear center with two vertical straight lines ([Formula: see text]) of singularity inside the class of all piecewise polynomials of degree [Formula: see text], we give the estimate of the maximum number [Formula: see text] of limit cycles bifurcating from the period annulus around the center based on the argument principle and the first order averaging theory. It shows that [Formula: see text] is at least [Formula: see text] bigger than the maximum number of limit cycles bifurcating from the period annulus around the linear center with two parallel straight lines of singularity in [Li &amp; Liu, 2015].

Влияние местоположения отвеса на точность определения крена дымовой трубы фотографическим способом

There is a method of using the corded plumb as vertical reference straight line, located in front of the objective of a digital photocamera in the article. When we take picture of the object under study, there will be this straight line in the photo, from which we can carry out all necessary measurements in the Paint system with the following conversion them into metric system. All possible variants of location of the reference straight line relative to it axis are considered by the example of the construction of the tower round shape and it is shown a method of heeling calculation by image processing results. Experimental research to determine the degree of influence of plumb location in the photo relative to it axe on the accuracy of the heeling determination was carried out by shooting the brick chimney with the 30 metres height when the plumb is located on the chimney axis and on different distance from the left and right of the axis. It is set in the result that the plumb location has influence on the accuracy of heeling determination. The optimal location is on the centre of the top section of the chimney and there is shown the method of accounting corrections due to inaccurate location.

Surface fine structure influence on saturated random packings.

Random packings of disks on a mesh are studied numerically using random sequential adsorption algorithm. The mesh is built of straight horizontal and vertical one-dimensional lines of a given distance between them. The packing fraction and structure as well as the kinetics of packing growth dependence on mesh size are analyzed to provide information, whether surface inhomogeneity will affect the properties of random packings. It has been shown that the number of disks in a packing slightly decreases with growing distance between mesh lines while the kinetics may change significantly even for very dense meshes. As packings obtained in random sequential adsorption resemble monolayers produced by irreversible adsorption processes, results of this study show that by measuring properties of a random packing it may be possible to determine fine structure of an underlying surface.

On the limit cycles of planar discontinuous piecewise linear differential systems with a unique equilibrium

This paper deals with planar discontinuous piecewise linear differential systems with two zones separated by a vertical straight line $ x = k $. We assume that the left linear differential system ($ x&lt;k $) and the right linear differential system ($ x&gt;k $) share the same equilibrium, which is located at the origin $ O(0, 0) $ without loss of generality.Our results show that if $ k = 0 $, that is when the unique equilibrium $ O(0, 0) $ is located on the line of discontinuity, then the discontinuous piecewise linear differential systems have no crossing limit cycles. While for the case $ k\neq 0 $ we provide lower and upper bounds for the number of limit cycles of these planar discontinuous piecewise linear differential systems depending on the type of their linear differential systems, i.e. if those systems have foci, centers, saddles or nodes, see Table 2.

Design, construction, characterization, and use of a detector to measure time of flight of cosmic rays

In the study of cosmic rays, measurements of time of flight and momentum have been used to identify incident particles from its physical properties, like mass. In this document we present the design, construction, characterization, and operation of a detector to measure time of flight of cosmic rays. The device is comprised of three small plates of plastic scintillator arranged in vertical straight line, coupled to one photomultiplier tube. The analogical output has been connected to a data acquisition system to obtain the number of digital pulses per millisecond. We present details of design, construction, operation, and preliminary results.

Evaluation of the influences of various force magnitudes and configurations on scoliotic curve correction using finite element analysis.

Scoliosis is a lateral curvature in the normally straight vertical line of the spine, and the curvature can be moderate to severe. Different treatment can be used based on severity and age of subjects, but most common treatment for this disease is using orthosis. To design orthosis types of force arrangement can be varied, from transverse loads to vertical loads or combination of them. But it is not well introduced how orthoses control scoliotic curve and how to achieve the maximum correction based on force configurations and magnitude. Therefore, it was aimed to determine the effect of various loads configurations and magnitudes on curve correction of a degenerative scoliotic subject. A scoliotic subject participated in this study. The CT-Scan of the subject was used to produce 3D model of spine. The 3D model of spine was produced by Mimics software and the finite element analysis and deformation of scoliotic curve of the spine under seven different forces and in three different conditions was determined by ABAQUS software. The Cobb angle in scoliosis curve decreased significantly by applying forces. In each condition depends on different forces, different corrections have been achieved. It can be concluded that the configurations of the force application mentioned in this study is effective to decrease the scoliosis curve. Although it is a case study, it can be used for a vast number of subjects to predict the correction of scoliosis curve before orthotic treatment. Moreover, it is recommended that this method and the outputs can be compared with clinical findings.

Design, construction, characterization and use of a detector to measure time of flight of cosmic rays

In the study of cosmic rays, measurements of time of flight and momentum have been used to identify incident particles from its physical properties, like mass. In this poster we present the design, construction, characterization, and operation of a detector to measure time of flight of cosmic rays. The device is comprised of three plates of plastic scintillator arranged in vertical straight line, they are coupled to one photomultiplier tube. The analogical output has been connected to a data acquisition system to obtain the number of digital pulses per millisecond. We present preliminary results.

Near-reversible efficient image resizing for devices supporting different spatial resolutions

Many devices in cloud environments support different spatial resolutions, necessitating image resizing of the original image contents. The goal of this paper is to combine multiple operators for image resizing in a stochastic optimization framework, seeking an optimal balance among essential resizing operators such as cropping and linear scaling. Specifically, we formulate image resizing as a MAP (maximum a posteriori) optimization problem with a Gibbs energy function. To reduce computational complexity we seek a sub-optimal solution of the MAP criterion with a deterministic implementation of the Metropolis algorithm. Since the optimization is carried out on the basis of a straight horizontal or vertical line in an image instead of the curved seam pixels, the optimization should converge quickly to have a fast image resizing. In addition, our image resizing can be associated with various user-defined content filtering such as a color masking. Finally, our resizing method is reversible, meaning that the image with the original size can be reconstructed from the retargeted image. This allows us to apply the proposed image resizing method to a prioritized image transmission with a scalable and progressive structure.