Search results for: Low velocity impact

Authors: M. Arockia Jaswin, D. Mohan Lal

Abstract:

Cryogenic treatment is the process of cooling a material to extremely low temperatures to generate enhanced mechanical and physical properties. The purpose of this study is to examine the effect of cryogenic treatment on the impact behavior of En 52 and 21-4N valve steels. The valve steels are subjected to shallow (193 K) and deep cryogenic treatment (85 K), and the impact behavior is compared with the valve steel materials subjected to conventional heat treatment. The impact test is carried out in accordance with the ASTM E 23-02a standard. The results show an improvement of 23 % in the impact energy for the En 52 deep cryo-treated samples when compared to that of the conventionally heat treated samples. It is revealed that during cryogenic treatment fine platelets of martensite are formed from the retained austenite, and these platelets promote the precipitation of fine carbides by a diffusion mechanism during tempering.

Keywords: Cryogenic treatment, valve steel, Fractograph, carbides, impact strength.

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Authors: E. Selçuk, Z. Karaçor, P. Yardımcı

Abstract:

Trade liberalization and its effects on the economies of developing countries have been investigated by many different studies, and some of them have focused on its impact on the current account balance. Turkey, as being one of the countries, which has liberalized its foreign trade in the 1980s, also needs to be studied in terms of the impact of liberalization on current account deficits. Therefore, the aim of this study is to find out whether trade liberalization has affected Turkey’s trade and current account balances. In order to determine this, yearly data of Turkey from 1980 to 2013 is used. As liberalization dummy, the year 1989, which was set for Turkey, is selected. Structural break test and model estimation results show that trade liberalization has a negative impact on trade balance but do not have a significant impact on the current account balance.

Keywords: Budget deficit, current account, liberalization, Turkish economy.

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Authors: Wang Jing, Tao Tao, Li Xiyuan, Pei Yifei

Abstract:

How to simulate experimentally the air flow and heat transfer under microgravity on the ground is important, which has not been completely solved so far. Influence of gravity on air natural convection results in convection heat transfer on ground difference from that on orbit. In order to obtain air temperature and velocity deviations of manned spacecraft during terrestrial thermal test, dimensionless number analysis and numerical simulation analysis are performed. The calculated temperature distribution and velocity distribution of the horizontal test cases are compared to the vertical cases. The results show that the influence of gravity is neglected for facility drawer racks and more obvious for vertical cabins.

Keywords: Gravity, Convection heat transfer, Manned spacecraft, Dimensionless number, Numerical simulation

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Authors: A. Irudaya Veni Mary, M. Victor Louis Anthuvan, P. Christie, A. Indira

Abstract:

In India, social enterprises are working to create social value in various fields including education; health; women and child development; environment protection and community development. Although social enterprises have brought about tremendous changes in the lives of beneficiaries, the importance of their works is not understood thoroughly. One of the ways to prove themselves is to measure the impact, which in recent times has received much attention. This paper focuses on the study of social value created by the social enterprises in the field of community development. It also aims to put forth a research tool for measuring the social value created by the social enterprises in the field of community development. A close-ended interview schedule was prepared to measure the social value creation and it was administered among 60 beneficiaries of two social enterprises who work in the field of community development. The study results show that the social enterprises have brought four types of impact in the life of their beneficiaries; economic impact, social impact, political impact and cultural impact. This study is limited to the social enterprises those who work towards community development. This empirical finding will enable the reader to understand various types of social value created by the social enterprises working in the field of community development. This study will also serve as guide for social enterprises in community development activities to measure their impact and thereby improve their operation towards the betterment of the society. This paper is derived from an empirical research carried out to describe the different types of social value created by the social enterprises in India.

Keywords: Social enterprise, social entrepreneurs, social impact, social value, tool for social impact measurement.

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Authors: Mohammad D. H. Beg, John O. Akindoyo, Suriati Ghazali, Abdullah A. Mamun

Abstract:

In this study, composites were fabricated from oil palm empty fruit bunch fiber and poly(lactic) acid by extrusion followed by injection moulding. Surface of the fiber was pre-treated by ultrasound in an alkali medium and treatment efficiency was investigated by scanning electron microscopy (SEM) analysis and Fourier transforms infrared spectrometer (FTIR). Effect of fiber treatment on composite was characterized by tensile strength (TS), tensile modulus (TM) and impact strength (IS). Furthermore, biostrong impact modifier was incorporated into the treated fiber composite to improve its impact properties. Mechanical testing showed an improvement of up to 23.5% and 33.6% respectively for TS and TM of treated fiber composite above untreated fiber composite. On the other hand incorporation of impact modifier led to enhancement of about 20% above the initial IS of the treated fiber composite.

Keywords: Fiber treatment, impact modifier, natural fibers, ultrasound.

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Authors: Priyanka Guin, Dibyendu Chatterjee, Arijit Roy

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Developing electronic system for detecting low energy impacts using open source hardware such as Arduino is challenging. A highly efficient loadcell is designed and fabricated. A commercial polyvinylidene fluoride (PVDF) piezoelectric film is used as primary sensor for sensing small impacts. Without modifying hardware, the Arduino board is configured by programming to capture the signal from the film sensor with a resolution better than 1.1 mV. By our system, impact energy as low as 1.8 µJ (corresponds to impact force of 39.9 mN) is reliably and monitored. In the linear zone, sensitivity of the system found to be as high as 20.7 kV/J or 3.3 V/N with a measurement frequency of 500 Hz. The various characteristics such as linearity, hysteresis, repeatability and spectrum analysis are discussed. After calibration, measurements of unknown impact energy and impact force are investigated and results are found to agree well.

Keywords: Arduino, impact energy, impact force, measurement system, PVDF film sensor.

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Authors: Eiko Takaoka, Ryohei Takahashi, Takashi Toyoda

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We installed solar panels and digital meteorological equipments whose electrical power is supplied using PV on July 13, 2011. Then, the relationship between the electric power generation and the irradiation, air temperature, and wind velocity was investigated on a roof at a university. The electrical power generation, irradiation, air temperature, and wind velocity were monitored over two years. By analyzing the measured meteorological data and electric power generation data using PTC, we calculated the size of the solar panel that is most suitable for this system. We also calculated the wasted power generation using PTC with the measured meteorological data obtained in this study. In conclusion, to reduce the "wasted power generation", a smaller-size solar panel is required for stable operation.

Keywords: Digital meteorological equipments, PV, photovoltaic, irradiation, PTC.

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Authors: N. Thongjub, B. Puangkird, V. Ngamaramvaranggul

Abstract:

The numerical simulation of the slip effect via vicoelastic fluid for 4:1 contraction problem is investigated with regard to kinematic behaviors of streamlines and stress tensor by models of the Navier-Stokes and Oldroyd-B equations. Twodimensional spatial reference system of incompressible creeping flow with and without slip velocity is determined and the finite element method of a semi-implicit Taylor-Galerkin pressure-correction is applied to compute the problem of this Cartesian coordinate system including the schemes of velocity gradient recovery method and the streamline-Upwind / Petrov-Galerkin procedure. The slip effect at channel wall is added to calculate after each time step in order to intend the alteration of flow path. The result of stress values and the vortices are reduced by the optimum slip coefficient of 0.1 with near the outcome of analytical solution.

Keywords: Slip effect, Oldroyd-B fluid, slip coefficient, time stepping method.

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Authors: Fatma Ghangir, Andrzej F. Nowakowski, Franck C. G. A. Nicolleau, Thomas M. Michelitsch

Abstract:

The performance of high-resolution schemes is investigated for unsteady, inviscid and compressible multiphase flows. An Eulerian diffuse interface approach has been chosen for the simulation of multicomponent flow problems. The reduced fiveequation and seven equation models are used with HLL and HLLC approximation. The authors demonstrated the advantages and disadvantages of both seven equations and five equations models studying their performance with HLL and HLLC algorithms on simple test case. The seven equation model is based on two pressure, two velocity concept of Baer–Nunziato [10], while five equation model is based on the mixture velocity and pressure. The numerical evaluations of two variants of Riemann solvers have been conducted for the classical one-dimensional air-water shock tube and compared with analytical solution for error analysis.

Keywords: Multiphase flow, gas-liquid flow, Godunov schems, Riemann solvers, HLL scheme, HLLC scheme.

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Authors: Raed H. Allawi

Abstract:

Fracture pressure is the main parameter applied in wells design and used to avoid drilling problems like lost circulation. Thus, this study aims to predict the fracture pressure of oil reservoirs in the southern Iraq Oilfield. The data required to implement this study included bulk density, compression wave velocity, gamma-ray, and leak-off test. In addition, this model is based on the pore pressure which is measured based on the Modular Formation Dynamics Tester (MDT). Many measured values of pore pressure were used to validate the accurate model. Using sonic velocity approaches, the mean absolute percentage error (MAPE) was about 4%. The fracture pressure results were consistent with the measurement data, actual drilling report, and events. The model's results will be a guide for successful drilling in future wells in the same oilfield.

Keywords: Pore pressure, fracture pressure, overburden pressure, effective stress, drilling events.

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Authors: Toshifumi Hiramatsu, Satoshi Morita, Manuel Pencelli, Marta Niccolini, Matteo Ragaglia, Alfredo Argiolas

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Automation technologies for agriculture field are needed to promote labor-saving. One of the most relevant problems in automated agriculture is represented by controlling the robot along a predetermined path in presence of rough terrain or incline ground. Unfortunately, disturbances originating from interaction with the ground, such as slipping, make it quite difficult to achieve the required accuracy. In general, it is required to move within 5-10 cm accuracy with respect to the predetermined path. Moreover, lateral velocity caused by gravity on the incline field also affects slipping. In this paper, a path-tracking controller for tracked mobile robots moving on rough terrains of incline field such as vineyard is presented. The controller is composed of a disturbance observer and an adaptive controller based on the kinematic model of the robot. The disturbance observer measures the difference between the measured and the reference yaw rate and linear velocity in order to estimate slip. Then, the adaptive controller adapts “virtual” parameter of the kinematics model: Instantaneous Centers of Rotation (ICRs). Finally, target angular velocity reference is computed according to the adapted parameter. This solution allows estimating the effects of slip without making the model too complex. Finally, the effectiveness of the proposed solution is tested in a simulation environment.

Keywords: Agricultural robot, autonomous control, path-tracking control, tracked mobile robot.

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Authors: S. Raja Balachandar, K. Kannan

Abstract:

A new Meta heuristic approach called "Randomized gravitational emulation search algorithm (RGES)" for solving large size set covering problems has been designed. This algorithm is found upon introducing randomization concept along with the two of the four primary parameters -velocity- and -gravity- in physics. A new heuristic operator is introduced in the domain of RGES to maintain feasibility specifically for the set covering problem to yield best solutions. The performance of this algorithm has been evaluated on a large set of benchmark problems from OR-library. Computational results showed that the randomized gravitational emulation search algorithm - based heuristic is capable of producing high quality solutions. The performance of this heuristic when compared with other existing heuristic algorithms is found to be excellent in terms of solution quality.

Keywords: Set covering problem, velocity, gravitational force, Newton's law, meta heuristic, combinatorial optimization.

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Authors: Ratchasak Suvannatsiri

Abstract:

The objectives of the research are to find the basic engineering properties of lateritic soil and to predict the impact on community members who live nearby the excavation pits in the area of Amphur Pak Thor, Ratchaburi Province in the western area of Thailand. The research was conducted by collecting soil samples from four excavation pits for basic engineering properties, testing and collecting questionnaire data from 120 community members who live nearby the excavation pits, and applying statistical analysis. The results found that the basic engineering properties of lateritic soil can be classified into silt soil type which is cohesionless as the loess or collapsible soil which is not suitable to be used for a pavement structure for commuting highway because it could lead to structural and functional failure in the long run. In terms of opinion from community members toward the impact, the highest impact was on the dust from excavation activities. The prediction from the logistic regression in terms of impact on community members was at 84.32 which can be adapted and applied onto other areas with the same context as a guideline for risk prevention and risk communication since it could impact the infrastructures and also impact the health of community members.

Keywords: Lateritic soil, excavation pits, engineering properties, impact on community members

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Authors: Mohamed M. Mousa, Aidarkhan Kaltayev

Abstract:

The equations governing the flow of an electrically conducting, incompressible viscous fluid over an infinite flat plate in the presence of a magnetic field are investigated using the homotopy perturbation method (HPM) with Padé approximants (PA) and 4th order Runge–Kutta method (4RKM). Approximate analytical and numerical solutions for the velocity field and heat transfer are obtained and compared with each other, showing excellent agreement. The effects of the magnetic parameter and Prandtl number on velocity field, shear stress, temperature and heat transfer are discussed as well.

Keywords: Electrically conducting elastico-viscous fluid, symmetry solution, Homotopy perturbation method, Padé approximation, 4th order Runge–Kutta, Maple

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Authors: John Walton, Vishal Parikh

Abstract:

Contact centres have been exemplars of scientific management in the discipline of operations management for more than a decade now. With the movement of industries from a resource based economy to knowledge based economy businesses have started to realize the customer eccentricity being the key to sustainability amidst high velocity of the market. However, as technologies have converged and advanced, so have the contact centres. Contact Centres have redirected the supply chains and the concept of retailing is highly diminished due to over exaggeration of cost reduction strategies. In conditions of high environmental velocity together with services featuring considerable information intensity contact centres will require up to date and enlightened agents to satisfy the demands placed upon them by those requesting their services. In this paper we examine salient factors such as Power Distance, Knowledge structures and the dynamics of job specialisation and enlargement to suggest critical success factors in the domain of contact centres.

Keywords: Post Taylorism, Knowledge Management, Power Distance, Organisational Learning

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Authors: E. Fosch-Villaronga

Abstract:

This paper pioneers Care Robot Impact Assessment (CRIA), a methodology used to identify, analyze, mitigate and eliminate the risks posed by the insertion of non-medical personal care robots (PCR) in medical care facilities. Its precedent instruments [Privacy and Surveillance Impact Assessment (PIA and SIA)] fall behind in coping with robots. Indeed, personal care robots change dramatically how care is delivered. The paper presents a specific risk-sector methodology, identifies which robots are under its scope and presents some of the challenges introduced by these robots.

Keywords: Ethics, Impact Assessment, Law, Personal Care Robots.

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Authors: Laith Jaafer Habeeb

Abstract:

The present study is concerned with the free convective two dimensional flow and heat transfer, within the framework of Boussinesq approximation, in anisotropic fluid filled porous rectangular enclosure subjected to end-to-end temperature difference have been investigated using Lattice Boltzmann method fornon-Darcy flow model. Effects of the moving lid direction (top, bottom, left, and right wall moving in the negative and positive x&ydirections), number of moving walls (one or two opposite walls), the sliding wall velocity, and four different constant temperatures opposite walls cases (two surfaces are being insulated and the twoother surfaces areimposed to be at constant hot and cold temperature)have been conducted. The results obtained are discussed in terms of the Nusselt number, vectors, contours, and isotherms.

Keywords: Numerical simulation, lid-driven cavity flow, saturated porous medium, different velocity and heated walls.

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Authors: Collins C. Chiemeke

Abstract:

Multichannel Analysis of Surface Wave (MASW) seismic method is widely used in geotechnical engineering for the measurement of shear wave velocity and evaluation of material property. This method was recently conducted at a Dam site located in Zaria, within the basement complex of northern Nigeria. The aim of this experiment was to make use of the MASW method in evaluating the strength of material properties of a section of the Dam embankment, which is vital to ascertain the safety of the Dam. The result revealed that, the material embankment showed general increase of shear wave velocity with depth. The range of shear wave velocities and the determined Poisson’s ratio falls within the normal range of consolidated rock material, indicating the Dam embankment is still consolidated. The range of shear modulus determined, also shows that the Dam embankment is rigid enough to withstand the shear stress imposed by the impounded water.

Keywords: Dam, MASW, Multichannel Analysis of Surface Wave, Seismic.

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Authors: M. H. Pol, A. Bidi, A.V. Hoseini, G.H. Liaghat

Abstract:

In this note, a theoretical model for analyzing of normal penetration of the ogive – nose projectile into metallic targets is presented .The failure is assumed to be asymmetry petalling and the analysis is performed by using the energy balance and work done .The work done consist of the work required for plastic deformation Wp, the work for transferring the matter to new position Wd and the work for bending of the petals Wb. In several studies, it has been shown that we can neglect the loss of energy by temperature. In this present study, in first, by assuming the crater formation after perforation, the value of work done is calculated during the normal penetration of conical projectiles into thin metallic targets. Then the value of residual velocity and ballistic limit of the projectile is predicated by using the energy balance. In final, theoretical and experimental results is compared.

Keywords: Ogive Projectile, normal impact, penetration, thinmetallic target.

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Authors: Santhakumar M., Asokan T.

Abstract:

This paper addresses the problem of trajectory tracking control of an underactuated autonomous underwater vehicle (AUV) in the horizontal plane. The underwater vehicle under consideration is not actuated in the sway direction, and the system matrices are not assumed to be diagonal and linear, as often found in the literature. In addition, the effect of constant bias of environmental disturbances is considered. Using backstepping techniques and the tracking error dynamics, the system states are stabilized by forcing the tracking errors to an arbitrarily small neighborhood of zero. The effectiveness of the proposed control method is demonstrated through numerical simulations. Simulations are carried out for an experimental vehicle for smooth, inertial, two dimensional (2D) reference trajectories such as constant velocity trajectory (a circle maneuver – constant yaw rate), and time varying velocity trajectory (a sinusoidal path – sinusoidal yaw rate).

Keywords: autonomous underwater vehicle, system matrices, tracking control, time – varying feed back, underactuated control.

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Authors: Shen Weishou, Ji Di, Zhang Hui, Yan Shouguang, Li Haidong, Lin Naifeng

Abstract:

Based on a long-term vegetation index dataset of NDVI and meteorological data from 68 meteorological stations in the Qinghai-Tibet plateau and their relations with major climate factors were analyzed. The results show the following: 1) The linear trends of temperature in the Qinghai-Tibet plateau indicate that the temperature in the plateau generally increased, but it rose faster in the last 20 years. 2) The most significant NDVI increase occurred in the eastern and southern plateau. However, the western and northern plateau demonstrate a decreasing trend. 3) There is a significant positive linear correlation between NDVI and temperature and a negative correlation between NDVI and mean wind speed. However, no significant statistical relationship was found between NDVI and relative humidity, precipitation or sunshine duration.4) The changes in NDVI for the plateau are driven by temperature-precipitation, but for the desert and forest areas, the relation changes to precipitation-temperature-wind velocity and wind velocity-temperature-precipitation.

Keywords: Qinghai-Tibet plateau, NDVI, climate warming.

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Authors: M. S. Khurram, S. A. Memon, S. Khan

Abstract:

Bed voidage behavior among different flow regimes for Geldart A, B, and D particles (fluid catalytic cracking catalyst (FCC), particle A and glass beads) of diameter range 57-872 μm, apparent density 1470-3092 kg/m³, and bulk density range 890-1773 kg/m³ were investigated in a gas-solid circulating fluidized bed of 0.1 m-i.d. and 2.56 m-height of plexi-glass. Effects of variables (gas velocity, particle properties, and static bed height) were analyzed on bed voidage. The axial voidage profile showed a typical trend along the riser: a dense bed at the lower part followed by a transition in the splash zone and a lean phase in the freeboard. Bed expansion and dense bed voidage increased with an increase of gas velocity as usual. From experimental results, a generalized model relationship based on inverse fluidization number for dense bed voidage from bubbling to fast fluidization regimes was presented.

Keywords: Axial voidage, circulating fluidized bed, splash zone, static bed.

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Authors: S. Raja Balachandar, K.Kannan

Abstract:

A new Meta heuristic approach called "Randomized gravitational emulation search algorithm (RGES)" for solving vertex covering problems has been designed. This algorithm is found upon introducing randomization concept along with the two of the four primary parameters -velocity- and -gravity- in physics. A new heuristic operator is introduced in the domain of RGES to maintain feasibility specifically for the vertex covering problem to yield best solutions. The performance of this algorithm has been evaluated on a large set of benchmark problems from OR-library. Computational results showed that the randomized gravitational emulation search algorithm - based heuristic is capable of producing high quality solutions. The performance of this heuristic when compared with other existing heuristic algorithms is found to be excellent in terms of solution quality.

Keywords: Vertex covering Problem, Velocity, Gravitational Force, Newton's Law, Meta Heuristic, Combinatorial optimization.

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Authors: Zarine Avetisyan

Abstract:

The present paper presents the discussion of scholars concerning speech impact, peculiarities of its realization, speech strategies and techniques in particular. Departing from the viewpoints of many prominent linguists, the paper suggests that manipulative argumentation be viewed as a most pervasive speech strategy with a certain set of techniques which are to be found in modern American political discourse. The precedence of their occurrence allows us to regard them as pragmatic patterns of speech impact realization in effective public speaking.

Keywords: Manipulative argumentation, political discourse, speech impact, technique.

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Authors: Mustafa Hasan Omar

Abstract:

The destruction effect of hydrocarbon solutions on concrete besides its high permeability have led researchers to try to improve the performance of concrete exposed to these solutions, hence improving the durability and usability of oil concrete structures. Recently, polymer concrete is considered one of the most important types of concrete, and its behavior after exposure to oil products is still unknown. In the present work, an experimental study has been carried out, in which the prepared epoxy polymer concrete immersed in different types of hydrocarbon exposure solutions (gasoline, kerosene, and gas oil) for 120 days and compared with the reference concrete left in the air. The results for outdoor specimens indicate that the mechanical properties are increased after 120 days, but the specimens that were immersed in gasoline, kerosene, and gas oil for the same period show a reduction in compressive strength by -21%, -27% and -23%, whereas in splitting tensile strength by -19%, -24% and -20%, respectively. The reductions in ultrasonic pulse velocity for cubic specimens are -17%, -22% and -19% and in cylindrical specimens are -20%, -25% and -22%, respectively.

Keywords: Epoxy resin, hydrocarbon solutions, mechanical properties, polymer concrete, ultrasonic pulse velocity.

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Authors: Collins C. Chiemeke, I. B. Osazuwa, Ibe S. O., Egwuonwu G. N., Ani C. D., Chii E. C.

Abstract:

The study area is Zaria, located in the basement complex of northern Nigeria. The rock type forming the major part of the Zaria batholith is granite. This research work was carried out to compare the responses of seismic refraction tomography and resistivity tomography in the same geologic environment and under the same conditions. Hence, the choice of the site that has a visible granitic outcrop that extends across a narrow stream channel and is flanked by unconsolidated overburden, a neutral profile that was covered by plain overburden and a site with thick lateritic cover became necessary. The results of the seismic and resistivity tomography models reveals that seismic velocity and resistivity does not always simultaneously increase with depth, but their responses in any geologic environment are determined by changes in the mechanical and chemical content of the rock types rather than depth.

Keywords: Environment, Resistivity, Response, Seismic, Velocity.

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Authors: Xiaohuan Li, Wangmin Yi, Xinghui Wu

Abstract:

In order to verify the performance of lunar lander structure, landing-impact test is urgently needed. And the test equipment is necessary for the test. The functions and the key points of the equipment are presented to satisfy the requirements of the test, and the design scheme is proposed. The composition, the major function and the critical parts’ design of the equipment are introduced. By the load test of releasing device and single-beam hoist, and the compatibility test of landing-impact testing system, the rationality and reliability of the equipment is proved.

Keywords: Landing-impact test, lunar lander, releasing device, test equipment.

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Authors: M. Azadbakht, N. Tajari, R. Alimoradzade

Abstract:

Knowing pea pods mechanical resistance against dynamic forces are important for design of combine harvester. In pea combine harvesters, threshing is accomplished by two mechanical actions of impact and friction forces. In this research, the effects of initial moisture content and needed impact and friction energy on threshing of pea pods were studied. An impact device was built based on pendulum mechanism. The experiments were done at three initial moisture content levels of 12.1, 23.5 and 39.5 (%w.b.) for both impact and friction methods. Three energy levels of 0.088, 0.126 and 0.202 J were used for impact method and for friction method three energy levels of 0.784, 0.930 and 1.351 J. The threshing percentage was measured in each method. By using a frictional device, kinetic friction coefficients at above moisture contents were measured 0.257, 0.303 and 0.336, respectively. The results of variance analysis of the two methods showed that moisture content and energy have significant effects on the threshing percentage.

Keywords: Pea pod, Energy, Friction, Impact, Initial moisture content, Threshing.

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Authors: M. Beisenbi, A. Sagymbay, S. Beisembina, A. Satpayeva

Abstract:

In this paper, the problem of unstable and deterministic chaotic processes in control systems is considered. The synthesis of a control system in the class of two-parameter structurally stable mappings is demonstrated. This is realized via the gradient-velocity method of Lyapunov vector functions. It is shown that the gradient-velocity method of Lyapunov vector functions allows generating an aperiodic robust stable system with the desired characteristics. A simple solution to the problem of synthesis of control systems for unstable and deterministic chaotic processes is obtained. Moreover, it is applicable for complex systems.

Keywords: Control system synthesis, deterministic chaotic processes, Lyapunov vector function, robust stability, structurally stable mappings.

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Authors: Catherine Maware, Olufemi Adetunji

Abstract:

The paper is aimed at developing a model to measure the impact of Lean manufacturing deployment on organizational performance. The model will help industry practitioners to assess the impact of implementing Lean constructs on organizational performance. It will also harmonize the measurement models of Lean performance with the house of Lean that seems to have become the industry standard. The sheer number of measurement models for impact assessment of Lean implementation makes it difficult for new adopters to select an appropriate assessment model or deployment methodology. A literature review is conducted to classify the Lean performance model. Pareto analysis is used to select the Lean constructs for the development of the model. The model is further formalized through the use of Structural Equation Modeling (SEM) in defining the underlying latent structure of a Lean system. An impact assessment measurement model developed can be used to measure Lean performance and can be adopted by different industries.

Keywords: Impact measurement model, lean bundles, lean manufacturing, organizational performance.

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