Land Width Research Articles

A Study on Parking Needs at Intersections – Case of Surat T. P. Schemes

Paper discusses parking needs at intersections of developed T. P. Schemes of Surat under the GTPUD Act, 1976. Land use and width of road along with existing parking facilities have an impact where the act has no specific provisions. Study identifies Parking consumes 0.1% - 2.46% road land at intersections.

Static analysis of hydrostatic conical bearings using flow resistance network method

Purpose – This paper aims to study the static characteristics of the hydrostatic conical journal bearings by utilizing single-action membrane restrictors to compensate the working pressures of recesses. Design/methodology/approach – The flow resistance network method is used to analyze the influences of load capacity and static stiffness of bearing with the design parameters, including the number of recesses, radial eccentricity ratio, axial displacement ratio, restriction constant, membrane compliance, length-diameter ratio, circumferential land width ratio, axial land width ratio and half of cone angle. Findings – This study shows the infinite stiffness of the oil produced in the first and second recesses while single-action membrane restriction constant of 2 and 3, respectively, as well as in the fourth recess while single-action membrane restriction constant of 0.01 and 0.1, respectively. Research limitations/implications – This article provides the hydrostatic conical bearings in static and unbiased states for analyses of design parameters. The analyses ignore dynamic pressure effect and do not use the Reynolds equation, and assuming that each oil recesses pressure is constant. Practical implications – The influences of the design parameters including the number of recesses, membrane restriction, membrane compliance, length-diameter ratio, half of con-angle, circumferential land width ratio, and axial land width ratio are discussed to the load capacity and static stiffness of conical bearing. Originality/value – Based on the characteristics of the conical bearing through analysis, this article suggests the front bearing with hard membrane restrictor (capillary) and the back bearing with soft membrane restrictor are the most appropriate for axial stiffness.

The relation between chip morphology and tool wear in ultra-precision raster milling

In the field of ultra-precision machining, the study of the relation between chip morphology and tool wear is significant, since tool wear characteristics can be reflected by morphologies of cutting chips. In this research, the relation between chip morphology and tool flank wear is first investigated in UPRM. A cutting experiment was performed to explore chip morphologies under different widths of flank wear land. A geometric model was developed to identify the width of flank wear land based on chip morphology. Theoretical and experimental results reveal that the occurrence of tool flank wear can make the cutting chips truncated at both their cut-in and cut-out sides, and reduce the length of cutting chips in the feed direction. The width of truncation positions of the cutting chip can be measured and used to calculate the width of flank wear land with the help of the mathematical model. The present research is potentially used to detect tool wear and evaluate machined surface quality in intermittent cutting process.

PENGARUH LUAS LAHAN PERTANIAN TERHADAP TINGKAT PENDAPATAN PETANI PADA DESA KEBONAGUNG KECAMATAN BALEREJO KABUPATEN MADIUN

The study entitled The Influence Of The Width Of The Agricultural Land To The Farmers Income Level In Kebonagung Village, Balerejo, Madiun has purposes : first, to determine wether the area of the agricultural land has real influence to the farmers income in Kebonagung Village, Balerejo, Madiun. Second, to determine wether the agricultural land partially gives influence to the farmers income in Kebonagung Village Balerejo Madiun.<br />Based on the result of data processing and simultaneously testing on a real level (a) = 5% indicates that the width of agricultural land stimultaneously has influence to the farmers income. It can be seen from the Fcount 523,132 , while Ft 3,97. In the other hand the Sighit 0,000 and Sigprob 0,05. The big influence of the land to the farmers income is shown by Rsquare 0,876. It means that 87% of the farmers income is influenced by the size of the land. While the rest 13% is influenced by another factor which are not included in this study.<br />The result of t test on agricultural land partially give influence it positively gives influence to the farmers income in Kebonagung Village, Balerejo, Madiun. It is proven by the analysis resulth that shows the tcount 232,8727 , ttabel 1,665 or Sighit 0,000 ≤ Sigprob 0,05<br />However , when it’s seen from the regretion equation the size of the land has negative influence. It’s shows by the regretion equation Y = -145966,589 + 1,0105 X. It can be condtuded from the regretion equation, that it the size of the land is increased by 1%. The income of the farmers will be decreased 1,0105 X, while another factor a held constant.

Topography-Based Surface Tension Gradients to Facilitate Water Droplet Movement on Laser-Etched Copper Substrates

This paper describes a method for creating a topography-based gradient on a metallic surface to help mitigate problems associated with condensate retention. The gradient was designed to promote water droplet migration toward a specified region on the surface which would serve as the primary conduit for drainage using only the roughness of the surface to facilitate the movement of the droplets. In this work, parallel microchannels having a fixed land width but variable spacing were etched into copper substrates to create a surface tension gradient along the surface of the copper. The surfaces were fabricated using a 355 nm Nd:YVO4 laser system and then characterized using spray testing techniques and water droplet (2-10 μL) injection via microsyringe. The distances that individual droplets traveled on the gradient surface were also measured using a goniometer and CCD camera and were found to be between 0.5 and 1.5 mm for surfaces in a horizontal orientation. Droplet movement was spontaneous and did not require the use of chemical coatings. The theoretical design and construction of surface tension gradients were also explored in this work by calculating the minimum gradient needed for droplet movement on a horizontal surface using Wenzel's model of wetting. The results of this study suggest that microstructural patterning could be used to help reduce condensate retention on metallic fins such as those used in heat exchangers in heating, ventilation, air-conditioning, and refrigeration (HVAC&R) applications.

Effect of cutting speed on tool life in ultrasonic-assisted milling process

Machining processes are inherently involved with tool wear, which is an influential factor in cutting forces, surface roughness, and machining costs. In conventional machining of some materials, there are some limitations regarding rapid wear of tool and large machining forces. As a result, new machining techniques have been developed in recent years, among which is the ultrasonic-assisted machining. This machining method is a combination of ultrasonic vibrations with conventional machining process. The goal of this article is to compare the tool life in ultrasonic-assisted milling and conventional milling processes. In experimental tests, one-dimensional ultrasonic vibrations have been applied on workpiece in the feed direction of tool. By varying spindle speed, the width of flank wear land of cutting tool has been obtained in ultrasonic-assisted milling and conventional milling processes, and the results are compared with each other. Due to tool rotation, the direction of workpiece vibrations with respect to edge of cutting tool varies in time. Consequently, there is the possibility of improper and uncontrolled contacts between tool and workpiece. In order to examine this issue, the relative speed of workpiece in normal direction of tool flank surface has been obtained analytically, and the results have been used in explaining the experimental observations. The experimental results have shown that in spindle speeds of n = 500, 1000, and 2000 r/min, tool life in ultrasonic-assisted milling process is less than in conventional milling process; however, for spindle speed of n = 3150 r/min, due to change in tool wear mechanism and decrease of relative speed of workpiece in normal direction of tool flank surface, tool life in ultrasonic-assisted milling process becomes larger than that in conventional milling process.

Practical challenges in determining piston ring friction

Practical challenges from both experiment and calculation sides were discussed for determining two piece twin land oil control ring friction. A floating liner engine was used for twin land oil control ring study. Effects of floating liner engine system dynamics and piston skirt friction were addressed and methods to mitigate them were discussed. A deterministic twin land oil control ring model was used for ring friction calculation. Variation of the surface roughness at different spots of the liner and its effects on both hydrodynamic and boundary lubrication predictions were discussed. A multi-point correlation method was introduced to address surface variation effects on the twin land oil control ring model. Ring land width variation between two lands as well as along the circumference and its effects on calculation were shown, and methods to address it were discussed. By taking all these necessary steps in both experiments and calculations, this study shows that a reasonable match can be achieved between the measured and calculated friction, which covers all three lubrication regimes. This study lays a foundation for realistically predicting the friction of piston rings in internal combustion engines.

Influencing the residual stresses in the surface layer by use of appropriate cutting parameters and tool geometries in turning of aluminium matrix composites

AbstractSurface properties of components often determine their proper functioning. More complex and increasing demands on operational systems require detailed understanding in the influence of machining on the surface layer. Besides surface structure, residual stresses are very important, especially for dynamically loaded boundary surfaces. But, for cutting of modern light weight construction materials like aluminium matrix composites there is insufficient information concerning residual stresses. On this account, experimental investigations in turning of SiC particle reinforced aluminium matrix composites with different cutting parameters and tool geometries are presented with the focus on residual stresses. They are determined by X‐ray diffraction analysis. The results show that in general the use of very small feeds, tools with a width of flank wear land of about 100 μm, or with a small corner radius cause high absolute values of the compressive residual stresses. In consequence, knowledge of the relation between machining and the residual stress state of the surface layer allows to selectively induce residual stresses in the surface layer. This can provide, for example, an increase of fatigue strength.

ANALISIS MOTIVASI BETERNAK SAPI POTONG BAGI PETERNAK LOKAL DAN TRANSMIGRAN SERTA PENGARUHNYA TERHADAP PENDAPATAN DI KECAMATAN KAIRATU, KABUPATEN SERAM BAGIAN BARAT

<p>The study was conducted in Kairatu District, Seram Bagian Barat Regency district from July to September 2008. Materials used in this study were 96 respondents of local and transmigrant cattle beef farmers with questionnaires. The samples were drawn from 4 villages, consisting of 2 villages of local peoples and 2 villages of transmigrants using purposive sampling technique, while the 97 respondents consisted of 49 local and 47 transmigrant beef cattle farmers who were drawn using convenience sampling technique. The objectives of the study: 1) to find out the difference in the motivation and the characteristics of the local and the transmigrant farmers, 2) to investigate the impact of characteristics of the local and the transmigrant farmers on their motivation, 3) to investigate the impact of the characteristics of the local and the transmigrant farmers on their income, and 4) to investigate the correlation between breeding motivation and income. The variables measured in this study were breeding motivation, farmers<br />characteristics and income. The data were collected and analyzed using software SPSS 17 to measure the breeding motivation level, the farmers’ characteristics and income. The results showed that the significant differences of characteristics between the local and the transmigrant farmers were age (P<0.01), education level (P<0.01), the braveness in risk taking (P<0.10), and working hours (P<0.05). The characteristics that had significant impact on the motivation were farming experience (P<0.05), number of dependants (P<0.05), width of agricultural land (P<0.10), and farmers’ dummy (P<0.01). The characteristics that had significant impact on income were age (P<0.05), education<br />level (P<0.05), farming experience (P<0.10), cattle beef ownership (P<0.05), and farmers’s dummy (P<0.05). The motivation of transmigrant farmers have positive relations to the income (P<0.10).</p><p><br />(Key words: Breeding motivation, Farmers characteristics, Local farmers, Transmigrant farmers, Economic motif,<br /> Non-economic motif, Income)<br /><br /></p>

Thin-film sensors with small structure size on flat and curved surfaces

We have developed a fabrication technology for thin-film sensors on metallic substrates with flat and curved surfaces. Physical vapour deposition by means of a magnetron sputtering system is used to deposit an insulating layer and a following functional layer. This layer is structured by distinct photolithographic steps utilizing a self-developed spray coating technique, four-axis robotics with micrometer precision and a UV laser with a spot size below 10 μm. This highly flexible technique allows a rapid change of design to produce various sensor layouts in a short time. Besides the fabrication technology, we present two realized applications for thin-film sensor technology in this paper. First, a tool wear sensor for rotating cutting tools, directly detecting the flank-wear land width, and second, sputtered resistance strain gauges for force measurement. Measurement results showing the potential of thin-film sensors are given briefly.

Pore-scale flow and mass transport in gas diffusion layer of proton exchange membrane fuel cell with interdigitated flow fields

Lattice Boltzmann method (LBM) is employed to investigate pore-scale flow and mass transport in a carbon paper gas diffusion layer (GDL) of interdigitated PEMFC. The carbon paper GDL is reconstructed using the stochastic method, and its macroscopic transport properties are numerically predicted. The predicted anisotropic permeabilities and effective diffusivity of the reconstructed GDL agree well with existing measurements. Then, effects of the porous structures of the carbon paper GDL are explored in terms of fluid flow, species transport and electrochemical reaction. The GDL porous structures greatly affect flow and mass transport, creating distinct specie concentration distribution and local current density distribution. Besides, simulations are performed to explore liquid water behaviors in the reconstructed GDL. The simulation results present a detailed description of the pore-scale liquid water behaviors. Further, simulations are performed to investigate the effects of land width and GDL contact angle on liquid water removal time and residual saturation. Narrower land reduces liquid water removal time and residual saturation. Higher contact angle increases the removal time and reduces the residual saturation.

Influence of non‐Newtonian behavior of lubricant on performance of hole‐entry hybrid journal bearings employing constant flow valve restrictors

Purpose – This paper aims to describe the theoretical study concerning the effect of non‐linear behavior of the lubricant on the performance of symmetric constant flow valve compensated hole‐entry hybrid journal bearing. The bearing performance characteristics have been computed for various values of non‐linearity factor, land width ratio, aspect ratio and external load.Design/methodology/approach – The analysis considers the generalized Reynolds equation governing the flow of lubricant having variable viscosity in the clearance space and equation of flow of lubricant through constant flow valve restrictor. The non‐Newtonian lubricant is assumed to follow the cubic shear stress law.Findings – The study indicates that for generation of accurate bearing characteristics data, the inclusion of non‐linear effects of lubricant in the analysis is essential.Originality/value – The performance characteristics in terms of minimum fluid‐film thickness, fluid‐film stiffness and damping coefficients, critical mass and...

Influence of the tool corner radius on the tool wear and process forces during hard turning

Hard turning has become an alternative machining process for grinding processes of hardened steels. One challenge during hard turning is the increasing wear during the operation time of the tool and the hereby influenced workpiece surface and subsurface properties. This causes unfavorable changes of the microstructure and residual stress state or rather damages of the subsurface. Important factors are the contact conditions between the tool and the workpiece. The width of flank wear land influences the size of the passive force significantly. This has a direct impact on the subsurface properties of the workpiece. One solution is to modify the contact conditions and thereby the specific mechanical and thermal loads that are applied to the tool as well as to the workpiece. This article presents an experimental approach of modified corner radius geometry of cutting tools for hard turning processes. Hereby, the size and direction of the contact length of the cutting edge are adjusted as well as the load impact during machining. The aim is to reduce the tool wear performance. The results show the potential of the load-specific tool design concerning the tool wear and the workpiece subsurface properties. Furthermore, a new approach for predicting the process forces during hard turning is presented.

PRODUKSI BERAS DI INDONESIA

Crop product especially rice is on of strategic and important commodities in Indonesian economic. The growing needs of rice because of the increasing population from year to year. It seems that domestic rice need projection, as principal food from year to year will increase as explained by USDA in the Agricultural Baseline Projection report to 20014. Import projection showed that until 2014 the domestic need for rice will increase 22-25 tons along with population increase, that is expected will reach 253 populations in 2014 (with growth rate of 1.49% per year). This research based on secondary data that is related with research variable: land width, productivity, unhulled paddy, rice production, and rice import. The used analysis model to test this hypothesis is Structural Equation Modeling (SEM) The results by using SEM showed that (1) land influence significantly and positively toward rice production (2) land influence positively and positively productivity (3) productivity influence positively and significantly toward rice production (4) productivity influence the rice import, (5) and production influence the rice import.

Impact of land width and channel span on fuel cell performance

The impact of land width and channel span on fuel cell performance was tested on 50 cm 2 flow fields. Combinations of land widths and channel spans of 0.25, 0.5 and 1.0 mm were evaluated. Polarization curves and high-frequency resistance were measured for several humidity levels for each of the flow fields. For performance at high current density, the land width was found to be the dominant factor. Reductions to the smallest size tested (0.25 mm) continued to showed improvement over wider lands. Adequate land fraction (preferably about 50%) needs to be provided to minimize contact resistance.

Enhancement of Surface Integrity in Turning of Particle74 Reinforced Aluminium Matrix Composites by Tool Design

Particle reinforced aluminium matrix composites (AMCs) are high-strength lightweight materials consisting of a comparatively soft aluminium alloy and hard embedded ceramic particles. The high hardness of the particles results in excellent abrasion resistance. However, this property lends poor machinability involving high tool wear and surface imperfections on the workpieces. For this reason, CVD diamond tipped indexable inserts were used for turning AA2124 with 25% volume proportion of SiC particles. The surface integrity is influenced by the tool geometry, which affects the stress condition in the shear zone. In the research described the influence of modified corner geometries and the width of flank wear land were investigated. The results showed that surface roughness values can be decreased by using tools with a wiper geometry. An increasing flank wear land width of the inserts led to a reduction of the surface imperfections.

Optimization of Channel Dimensions in the Flow-Field for PEMFC

This paper focuses on the improvement of the distribution uniformity and consumption rate of the hydrogen (H2) in proton exchange membrane (PEM) fuel cells via optimization of the channel dimensions in the flow-field of bipolar plates. Based on the half-cell model for the anode side numerical simulation is carried out with computational fluid dynamics software Fluent. The method of DOE (Design of Experiment) is used in the simulation, and the results show that channel depth is the most influential factor to H2 consumption rate, channel width comes second, and land width has the least influence.

Tool-Swinging Cutting of Binderless Tungsten Carbide

Tool wear reduction is very important in cutting of ultra hard and brittle materials. In this paper, a tool-swinging cutting method was applied to reduce the wear of round-nosed diamond tools in cutting of tungsten carbide (WC). In this method, the geometrical center of the cutting edge was adjusted to be in coincidence with the rotation center of the B-axis table, and thus the cutting point could be changed along the cutting edge by swinging the tool about the B-axis center. Experimental results showed that the width of the flank wear land was greatly reduced compared to that in the conventional cutting. This work can shed light on ultraprecision machining WC parts without or with less need for subsequent polishing process.

Tool Wear Mechanisms in High Speed Machining Ductile Cast Iron

Wear behavior of WC based nanocomposite cutting tool when high speed cutting ductile cast iron was investigated. Orthogonal cutting tests were carried out on a CA6140 lathe using three speeds, namely, 100, 215 and 287m min-1. The WC based nanocomposite tool is found to be superior to cemented carbide tools (YG8). The tool life is prolonged 60% as compared to cemented carbide, as the width of the wear land (VB), which was monitored at selected time intervals. Meanwhile, the topography of worn surfaces was scanned by a profilemeter. Wear characterization of the rake face and the flank surfaces as well as of the collected chips was conducted using a scanning electron microscopy (SEM). Results showed that distinctive traces of single abrasive tool wear event were found on the rake face of the tool, additionally, the adhesion wear is the main wear mechanism in the flank face of the tool. However, the extent of improvement in tool life depends strongly on the cutting conditions, with the greatest benefits being seen at higher cutting speeds and feed rates.

Influence of Channel Dimensions on Behavior of a Polymer Electrolyte Membrane Fuel Cell

In this study, we present a fuel cell model that takes into account of the heat and mass transfers in the Membrane Electrolyte Assembly (MEA). The studied model is based on a transient model by combining independent descriptions of heat and mass transfers in the cell with a third description of coupled charge and mass transfers in the electrodes. We used this model with different dimension of the bipolar plate channel to study the effect of the channel dimension on internal heat generation of a polymer electrolyte membrane fuel cell width. Optimum values for each of the dimensions (channel width, land width and channel depth) were obtained. Consequently, their use would lead to improved fuel cell efficiency.