Horizontal Side Research Articles

Gravitational search algorithm for probabilistic design of HBPS canals

In this study, the performance of a recent meta-heuristic technique, namely, gravitational search algorithm (GSA) is evaluated for a deterministic as well as for a probabilistic design of canals that have cross-sectional shape of horizontal bottom and parabolic sides (HBPS). The uncertainty in various input parameters is modeled using probabilistic approach and a modified chance-constrained model is presented for an optimal design of HBPS canals with the aim of minimizing the total cost, while satisfying the basic flow constraints and reliability constraints on the canal capacity and overtopping. First, the GSA method is applied to solve the HBPS canal design problem under different constraints, and its performance is evaluated by comparing with the solutions of the deterministic models by the particle swarm optimization and genetic algorithm. Then, the GSA is applied to obtain the solution of the probabilistic model and in view of multiple conflicting goals; pseudo-weight vector approach is adopted to assist in decision-making and demonstrate its applicability for arriving at a suitable decision. The results obtained suggest that the proposed GSA approach has good potential for a reliable and cost-effective design of canals.

Numerical simulation of natural convection between a decentered triangular heating cylinder and a square outer cylinder filled with a pure fluid or a nanofluid using the lattice Boltzmann method

Natural convection around a decentered triangular cylinder placed in a square cylinder is studied numerically using the lattice-Boltzmann method. The study is conducted for pure water and water–silver nanofluid. The inner heating triangular cylinder is maintained at a constant and uniform temperature while the vertical/(horizontal) sides of the external cylinder are cooled at constant temperature/(considered adiabatic). The numerical analysis is carried out for three decentered positions of the triangular block toward the left side of the outer square cylinder; these are Left-Bottom (LB), Left-Middle (LM) and Left-Top (LT). The other parameters governing the problem are the Rayleigh number (103≤Ra≤107), the Prandtl number of the pure water (Pr=7) and the volume fraction of nanoparticles (0≤φ≤0.1). The effective thermal conductivity and viscosity of nanofluids are calculated using Maxwell–Garnetts (MG) and Brinkman models, respectively. The results obtained show that fluid flow and heat transfer characteristics are highly affected by the heating cylinder position. The increase of nanoparticles volume fraction has a positive impact on the average Nusselt number for all considered positions of the heating block. Results of the block's positions on the vertical centerline of the outer cylinder are also presented and discussed for comparison purposes. In dominating natural convection regime, it is found out that the bottom/(top) position of the block becomes the most/(least) favorable to heat transfer.

Mathematical Characterization of Bénard-Type Geothermal Scenarios Using Discriminated Non-dimensionalization of the Governing Equations

Abstract The classical non-dimensionalization process of governing equations is a low-cost method commonly applied for a first approximation to the dimensionless numbers that determine the solution patterns in many problems; however, this procedure fails in complex problems, where it is not even possible to define reference quantities – because they are not established in the statement of the problem – to make the dependent or independent variables dimensionless. The application of discrimination corrects this obstacle and allows suitable dimensionless groups to be defined. These, in turn, have two interesting properties: (i) they are of order of magnitude unity, and (ii) they have a clear meaning in terms of balance of physical quantities that counteract each other in a domain or sub-domain of the problem. In this paper, discriminated non-dimensionalization is applied to geothermal scenarios of Bénard-type convective flow, large horizontal boundary sides under a temperature gradient in porous media, to determine the dimensionless groups that control the steady temperature and stream patterns and, from these, the order of magnitude of the main unknowns of the problem. The results were checked numerically for many cases.

IJIREEICE - Electrical, Electronics, Instrumentation and Control

3 Abstract: As technology scales, sub-threshold leakage currents grow exponentially and become an increasingly large component of total power dissipation. To improve performance of the MOSFETs, doping profile of channel is changed. In this paper, we present comparison of uniform doping (UD), horizontal high source side doping (HHSS) &horizontal high drain side doping (HHDS) and draw the various characteristics i.e. channel electric field, surface potential & sub threshold leakage current .our results show that the horizontal high source sidedoping exhibit excellent properties not only higher mobility but also hot electron degradation improvement and better reliability. Therefore, refer to the results, horizontal high source side doping structure has superior performances in comparison with uniform and horizontal high drain side doping (HHDS). All the device simulations are performed using SILVACO Atlas device simulator.

Numerical Simulation of Blasting-Induced Damage in Grouting Curtain of Sandstone Aquifer for Vertical Shaft

To provide a theoretical basis for water prevention and control methods and reasonable supporting techniques for vertical shaft, and to ensure the shaft construction to pass the sandstone aquifer safely and rapidly, numerical simulation using dynamic damage constitutive model, which was a user-defined constitutive modules in FLAC3D, a lagrangian analysis code in three dimensions, has been applied to investigate the dynamic damage effect in the surrounding rock of the grouting curtain near the driving working face for vertical shaft excavated by blasting. The results indicate that the distribution of the damage zone in the surrounding rock of the shaft, which decreases the effective thickness of the grouting curtain, was like a ellip-se, and that the depth of the damage zone in the surrounding rock of the shaft grouting curtain is fewer than that of the driving face floor. It can be concluded that the centre part of the driving face floor, especially the cutting hole zones, and the shaft wall in the greater horizontal stress side are the " key parts " for shaft water prevention and control methods.

Evaluation of Specific Spinal Segmental Stabilizing Exercises in the Treatment of Antenatal Low Back Pain

Aims: To investigate the effect of specific lumbar stabilizing exercises on relieving antenatal low back pain. Study design: A randomized clinical controlled trial. Place and Duration of study: Department of Obstetrics (antenatal clinic), Kafelsheikh general hospital - Kafelsheikh, between October 2014 and January 2015. Methodology: Twenty pregnant women (age 20-25 years) at 20-24 weeks gestation, clinically diagnosed with low back pain and divided into 2 equal groups (A&B). Patients in group A were treated by lumbar stabilizing exercises for 12 weeks, patients in group B without any treatment. Low back pain intensity and spine flexibility were measured by mean of a 100-mm horizontal visual analogue scale and side bending test before and after the treatment program. Results: Patients in group A showed significant decrease in low back pain intensity (P=0.01) and spine flexibility (P=0.01), while in group B there were significant increase in low back pain intensity (P=0.01) without difference in spine flexibility (Right and Left sides) (P=0.83 and 0.6) at the end of the study. There were no significant differences in low back pain intensity (P=0.82) and spine flexibility (Right and Left sides) (P=0.76 and 0.69) at the beginning of the study. But there were highly significant differences in low back pain intensity (P=0.001) and spine flexibility (Right and Left sides)(P=0.01) at the end of the study between both groups, Conclusion: lumbar stabilizing exercises decrease the pain intensity and increase the lumbar range of motion.

Determination of the Stress State of a Piecewise Homogeneous Elastic Body with a Row of Cracks on an Interface Surface Subject to Antiplane Strains with Inclusions at the Tips

The stress state of a bimaterial elastic body that has a row of cracks on an interface surface is considered. It is subjected to antiplane deformations by uniformly distributed shear forces acting on the horizontal sides of the body. The governing equations of the problem, the stress intensity factors, the deformation of the crack edges, and the shear stresses are derived. The solution of the problem via the Fourier sine series is reduced to the determination of a singular integral equation (SIE) and consequently to a system of linear equations. In the end, the problem is solved in special cases with inclusions. The results of this paper and the previously published results show that the used approach based on the Gauss-Chebyshev quadrature method can be considered as a generalized procedure to solve the collinear crack problems in mode I, II, or III loadings.

The influence of a balanced structure on the rotation effect of a build-up system

The influence of a balanced structure on the rotation effect of a build-up system was investigated using an orthogonal array, which can efficiently reduce the total number of experiments. Based on mechanical analysis, four primary influence factors of the balanced structure were specified, including the thickness, material and shape of the balanced platen, and the height of the bearing outer ring. Finite element method (FEM) was employed to investigate the relationship between four factors and the maximum differential of the horizontal side force (Fm) on a force transducer in the measurement of different orientations. We found that by decreasing the Fm, less rotation effect of the build-up system would be. The results of FEM simulations and the related assumption were validated by orthogonal-array experiments results. Furthermore, FEM simulations for the effects of the height of the bearing outer ring demonstrated that the magnitude of Fm initially decreases with increasing the height of the bearing outer ring, but then levels off.

DEVELOPMENT AND EVALUATION OF SMALL-SCALE POWER WEEDER

Small-scale power weeders are an important and challenging task in many countries, where the farm size in hectare per capita is very low and is declining over time. Therefore, the development of suitable mechanized weeding methods is an imperative to meet the demand for farmers. An economical mechanical power weeder that can be used as inter and intra-row weeding method was developed and evaluated in triple hybrid 314 variety of maize. Developed power weeder consisted of engine, blades assembly and transmission system. Modified vertical blades were used with the weeder and mounted on a circular rotating element on its horizontal side; the motion was transferred to blades units by amended transmission system. The effect of weeder forward speeds, depth of operation, number of blades and soil moisture content on fuel consumption, plant damage, weeding index, effective field capacity, field efficiency, energy required per unit area and total cost were studied. Three levels of soil moisture content (7.73, 12.28 and 16.18 %), two blades arrangements (two and four vertical blades for each unit), three weeder forward speeds (1.8, 2.1 and 2.4 km/h) and two depths of operation (from 0 to 20 and from 20 to 40 mm) have been chosen. The results showed that, the minimum value of fuel consumption was 0.546 l/h and recorded by using two blades with 1.8 km/h weeder forward speed at depth of operation ranged from 0-20 mm and soil moisture content 16.18 %. The highest field efficiency was 89.88% by using two blades with 1.8 km /h weeder forward speed at depth of operation ranged from 0 to 20 mm and soil moisture content 16.18%. The minimum value of effective field capacity was 0.198 fed/h by using four blades, weeder forward speed 1.8 km/h, soil moisture content 7.73% and under depth of operation ranged from 20-40 mm. The lower value of total cost was 55.09 L.E /fed and was obtained by using two blades with 2.4 km/h weeder forward speed at depth of operation ranged from 0-20 mm and soil moisture content 16.18 %.

Influence of Lateral Walls on Peristaltic Flow of a Couple Stress Fluid in a Non-Uniform Rectangular Duct

In the present investigation we have studied the peristaltic flow of a couple str ess fluid in a non-uniform rectangular duct. The flow is investigated in a wave frame of reference moving with the velocity c away from the fixed frame. The peristaltic waves propagating on the horizontal side walls of a non-uniform rectangular duct is studied under lubrication approach. The exact solutions of velocity and pressure gradient have been found under lubrication approach. The pumping characteristics, axial pressure gradient, velocity field and trapping phenomena have been discussed to highlight the physical features of emerging parameters of couple stress fluid.

Do horizontal relationships matter to production and operations managers?

This paper shifts the focus of production, operations and supply chain management business relationships from the vertical to the horizontal side and calls for more research on this issue. The main intent is to provide managerially oriented arguments regarding the linkages between the achievement of operations-related goals and decisions related to horizontal business relationships. Specifically, we address the following research question: Does a linkage exist between production and operations objectives and the decisions a company makes about horizontal agreements, particularly horizontal governance mode choice? To answer this research question, we develop literature-based hypotheses and collect data from 4316 agreements of mergers and acquisitions and alliances and joint venture announced and completed between 2000 and 2010 by 88 of the first 100-ranked members of the Fortune 500 in the year 2000. We then test the hypotheses through a binary logistic regression model. This study brings interesting results and findings in terms of how and why production management considerations should play a crucial role in the type of strategic decisions that are usually reserved for finance and strategy managers. Operations managers should be fully involved in such decisions if they are to be well acquainted about how their choices impact on operational objectives.

An Investigation on the Effect of Design Parameters of Side Guide on Camber in Hot Slab Rolling

In this study, we present a systematic approach for examining the effects of the design parameters of the side guide on camber, a phenomenon in which a material with a temperature gradient across its width is bent in the right or the left direction as the material is deformed in the roll gap. A series of finite element (FE) analyses were performed to provide a set of computed values for selected design parameters, such as (i) the length of the side guide, (ii) the diameter of guiding roller attached to the contact face of the side guide, (iii) the pitch of the guiding rollers and (iv) the interference of the guiding roller into the slab, that would decrease significantly the contact time between the slab and the side guide, and reduce the contact force between them. In the FE analyses, the actual sizes of the horizontal rolls (work rolls), vertical rolls (edgers) and side guide were modeled. Based on the results of the FE analyses, the side guide was designed and manufactured for installation in the POSCO No. 2 Hot Strip Mill. When the side guide was installed in front of work roll, camber was reduced dramatically by 57%. The design parameter that had the most influence on camber was the length of the side guide. In terms of side guide durability, the interference of guiding roller into the slab was the most dominant design parameter.

The Number of Emitters Alters Salt Distribution and Root Growth in Potted Gerbera

Potted gerberas were grown in a greenhouse with one, two, or four emitters (1.2 L·h−1) per pot and irrigated with water of two levels of salinity (1.5 dS·m−1 and 3 dS·m−1). All pots received the same volume of water. The aim was to determine whether the number of emitters per pot affects the distribution of roots and salts in the substrate (100% coconut fiber). We determined the electrical conductivity (EC) distribution at three different heights (upper, middle, and lower). We also studied the roots and EC horizontal distribution in four quadrants (southeast, southwest, northwest, and northeast). Shoot growth, leaf damage, plant water status, and photochemical capacity of photosystem II were also studied. Two or four emitters per pot reduced the leaching fraction compared with that observed with one emitter, improving both the amount and homogeneity of substrate moisture. In the two saline conditions used, the salt concentration in the substrate was irregular both vertically and horizontally, and the presence of roots in the horizontal quadrant sides was heterogeneous. Both of these behaviors decreased as the number of emitters per pot increased. Root growth was weakly related with the soluble salt content in the root zone. When saline water is used, two emitters per pot are to be recommended because the difference between using two and four emitters was very slight. The use of only one emitter reduced shoot and root growth and encouraged salt damage to leaves.

INSTITUTIONAL ENVIRONMENT FOR ICT UTILIZATION IN RURAL INDIA

Agriculture is one of the most important sectors in India, and could benefit tremendously with the applications of ICTs especially in bringing changes to socio-economic conditions of the poor in rural areas. Achieving these benefits requires proper institutions for ICT adoption and utilization. Therefore The current state of major Indian institutions (ICT and rural policies) using document analysis is evaluated against supporting progress in areas of the horizontal side of the “cube framework” in rural India. Major finding is that The Five Year Plans, National ICT and Telecom Policies are developing in the right direction and government initiatives are increasingly maturing, but may lack some specific solutions.

Study of L-shaped resonators at terahertz frequencies

In experimental and theoretical studies of terahertz subwavelength “L”-shaped structure, we proposed an unusual-mode current resonance responsible for low-frequency characteristic dip in transmission spectra. Comparing spectral properties of our designed simplified structures with that of split-ring resonators, we attribute this unusual mode to the resonance coupling and splitting under the broken symmetry of the structure. Furthermore, it is found that this phenomenon is also related to not only the spacing between horizontal and vertical sides but also their relative position in “L” structure, showing the weakened coupling and spectral splitting with the increased distance and structure symmetry.

Liquid sloshing in partly-filled laterally-excited circular tanks equipped with baffles

Linear potential theory in conjunction with the conformal mapping technique are employed to develop rigorous mathematical models for two-dimensional transient sloshing in non-deformable baffled horizontal circular cylindrical vessels, filled with inviscid incompressible fluids to arbitrary depths, and subjected to arbitrary time-dependent lateral accelerations. Three common baffle configurations are considered, namely, a pair of free surface-touching horizontal side baffles, and a central surface-piercing or bottom-mounted vertical baffle of arbitrary extension. The first few normalized antisymmetric/symmetric sloshing frequencies of the partially-filled tanks are tabulated for selected baffle extension and fill depth ratios. Also, the effects of liquid fill depth or baffle length parameter on the impulsive, total and modal convective mass ratios are examined. A ramp-step function is used to replicate the lateral acceleration excitation encountered in an idealized turning maneuver. Durbin's numerical Laplace transform inversion scheme was applied to solve the resulting truncated linear sets of ordinary differential equations in the time-domain. The effects of excitation input time, fill level, and baffle configuration/extension on the force and moment amplification factors are illustrated through appropriate design charts. Furthermore, the transient hydrodynamic responses to a real seismic event are calculated and the effectiveness of baffle configuration/length on suppression of the induced destabilizing lateral forces are examined. Limiting cases are considered and rigorous verifications are made by comparison with the available data as well as with the numerical simulations performed by using a commercial CFD software package.

Optimal design of drainage channels using probabilistic search

Optimal design of artificial drainage channels is essential for the planning and management of irrigation projects. In this paper a special class of drainage channel with horizontal bottom and parabolic sides (HBPS) is designed using a recent meta-heuristic optimisation tool, namely probabilistic global search Lausanne (PGSL). The solutions of different models are found to be competitive with those obtained by classical optimisation procedures and particle swarm optimisation (PSO). The trend and sensitivity analyses show that more attention is needed in maintaining the design bed slope while implementing channels in real field conditions. Uncertainties associated with channel design parameters are incorporated in the design by applying first-order second-moment (FOSM) formulations. Two probabilistic channel design models are considered, one with overtopping probability constraint and another with a channel capacity constraint, and the solutions are obtained in the PGSL environment. To improve practical usefulness, both the models are further modified by adding geometric constraints on top width and flow depth and solutions are obtained. The presented PGSL approach is found to be capable of handling varying degrees of complexity and is proven to be suitable even for channels with more complex profiles than that of simple trapezoidal channels.

Probabilistic multi-objective optimal design of composite channels using particle swarm optimization

To achieve cost effectiveness and reliability in design, this paper presents a probabilistic multi-objective model for optimal design of composite channels that have a cross-sectional shape of horizontal bottom and parabolic sides. The multiple objectives of channel design include minimizing the cost of channel construction, maximizing the probability of the expected channel capacity being greater than the design flow and minimizing the overtopping probability. In this study, the principles of first-order uncertainty analysis are adopted for handling uncertainty in parameters of the problem. The optimization model is solved using the particle swarm optimization method and Pareto-optimal solutions are generated for various combinations of overtopping probability and exceedance probability of channel capacity. The results show that the presented approach has good potential for exploring different alternative designs of open channels under input parameter uncertainty.

Uncertainty Underprediction in Monte Carlo Eigenvalue Calculations

It is well-known that statistical estimates obtained from Monte Carlo criticality simulations can be adversely affected by cycle-to-cycle correlations in the fission source, which can lead to estimates of statistical uncertainties that are lower than the true uncertainty by a factor of 5 or more. However, several other more fundamental issues such as adequate source sampling over the fissionable regions and source convergence can have a significant impact on the uncertainties for the calculated eigenvalue and localized tally means, and these issues may be mistaken for effects resulting from cycle-to-cycle correlations. In worst-case scenarios, the uncertainty may be underpredicted by a factor of 40 or more. Since Monte Carlo methods are widely used in criticality safety applications and are increasingly being used for benchmarking reactor analyses, an in-depth understanding of the effects of these issues must be developed in order to support the practical use of Monte Carlo software packages.A rigorous statistical analysis of eigenvalue and localized tally results in Monte Carlo criticality calculations is presented using the SCALE/KENO-VI (continuous-energy version) and MCNP codes. The purpose of this analysis is to investigate the underprediction of uncertainty and its sensitivity to problem characteristics and calculational parameters using two of the most widely used Monte Carlo criticality codes. For the problems considered here, which are fuel rod and fuel assembly problems with reflecting boundary conditions on all four horizontal sides, we show that adequate source convergence along with proper specification of Monte Carlo parameters can reduce the magnitude of uncertainty underprediction to reasonable levels, below a factor of 2 in most cases.

Self-Assessment System: Detrimental Effects upon Entrepreneurial and Innovative Activity

Efficient regulatory mechanisms that induce innovation, co-operation and deter competition law infringements have recently been the subject of growing attention. Competition is essential to the innovation process which in general terms enables entrepreneurship. But so too is co-operation between firms which requires an exchange of information and may lead to inefficient collusive behaviour. The optimal trade-off between the provision of stable entrepreneurial incentives and the new European competition law’s reform with the self-assessment system has been largely missing from the current scholarly debate. This paper identifies the unintended horizontal side effects of this new self-assessment system upon the entrepreneurial activity, offers a legal evaluation of the optimal entrepreneurial incentive mechanisms and provides legal and economics arguments for an improved regulatory response.