Kinds Of Pads Research Articles

STRATEGI OPTIMALISASI PENERIMAAN RETRIBUSI PARKIR TEPI JALAN UMUM DI KOTA DUMAI

Street parking retribution is one kind of PAD that has high potential in Dumai City.However, income from street parking retribution in Dumai City is still low because there is no proper strategy to optimize it. Therefore, the purpose of this research is to formulate strategy in order to optimize the income of parking on the street in Dumai City.This research uses interviews, questionnaires, observation and study documents as data collection techniques. Then data founded processed by calculating IFAS-IFAS, Cartesian SWOT quadrant, IE matrix and SWOT analysis. Results of this research are the formulation of strategies for optimizing the street parking retribution income in the city of Dumai as follows: 1) implementing the Electronic Parking Terminal (TPE) system as a more effective replacement system. 2) Forming supervisory team by coordinating such as Satpol PP, Police and so on. 3) Installed Closed Circuit Television (CCTV) at each public roadside parking location so that it can be used in the future. 4) Open a written or online complaint service to receive input and complaints from the public or public roadside parking service users. 5) Propose an additional operational budget so that the expansion of public roadside parking spaces in Dumai City can be carried out.

Fe–Al alloy for eco-friendly copper-free brake-pads

Copper (Cu) is almost an essential constituent of friction materials (FMs) since it shows multi-functionality in performance. However, it is being banned due to its adverse effects on aquatic life. In the present research work, iron-aluminum (FA25) alloy particles were explored for Cu replacement. With the help of fixed parent composition, five types of brake-pads were manufactured with variations in FA25 alloy content as 0, 5, 10, 15, and 20 wt%. One more kind of pad was developed containing Cu in 10 wt% for the sake of comparison. The brake-pads were characterized for physical, mechanical, thermal, tribological properties and noise-vibration (NV) performance. The 10 wt% alloy proved to be the optimum amount to replace the Cu with superior performance if fade resistance and counterface friendliness can be compromised slightly.

Study of <i>q</i>-Garnier System by Padé Method

We give a simple form of the evolution equation and a scalar Lax pair for the $q$-Garnier system. Some reductions to the $q$-Painlev\'e equations and the autonomous case as a generalized QRT system are discussed. Using two kinds of Pad\'e problems on differential grid and $q$-grid, we derive some special solutions of the $q$-Garnier system in terms of the $q$-Appell Lauricella function and the generalized $q$-hypergeometric function.

Nonlinear Compression Behavior of the Grooved Polishing Pad: A Model and Its Validation

Stiffness analysis of the grooved pad is important to study the mechanical action and slurry flow in CMP process. This paper investigates the nonlinear compression behavior of the grooved pad and then presents a mathematical model to calculate the compressive stiffness of the polishing pad with micro roughness and macro grooved textures. The compressive stiffness of two kinds of pads with different surface structures is analyzed. The results are compared with the FEM model and the uniform thick layer (UTL) model, which are extensively employed in the analysis of pad stiffness. It verifies that the proposed model shows a good agreement with the FEM model. Additional experiments are conducted to validate the accuracy of the proposed semi-empirical formula considering the compressive stiffness of the asperity layer. It is worth mentioning that the error will be more than 24% in calculating the tested grooved pad stiffness by traditional UTL model. In the proposed model, the relationship between the pad stiffness and the geometrical parameters is depicted explicitly, which is convenient for designing the groove structure to achieve a desirable polishing performance.

MEGARA Optics: stain removal in PBM2Y prisms

MEGARA is the new integral-field and multi-object optical spectrograph for the GTC. For medium and high resolution, the dispersive elements are volume phase holographic gratings, sandwiched between two flat windows and two prisms of high optical precision. The prisms are made of Ohara PBM2Y optical glass. After the prisms polishing process, some stains appeared on the surfaces. For this, in this work is shown the comparative study of five different products (muriatic acid, paint remover, sodium hydroxide, aqua regia and rare earth liquid polish) used for trying to eliminate the stains of the HR MEGARA prisms. It was found that by polishing with the hands the affected area, and using a towel like a kind of pad, and polish during five minutes using rare earth, the stains disappear completely affecting only a 5% the rms of the surface quality. Not so the use of the other products that did not show any apparent result.

Experimental performance analysis of a solar evaporative cooler with three different types of pads

This article presents the operation of a simple DC-powered solar evaporative cooler which was designed in the University of Tehran. This suggested design aims to implement innovation by using the minimum of energy to cool a room and concentrates on solar cooling technology. In the present paper, we describe how it can be useful, without wasting a lot of energy. The cooler was tested in a specified room for measuring different temperatures at different locations in the room and comparing the results in the summer during sequential days in order to evaluate the performance of the cooler. Three kinds of pads are used in the cooler including a conventional pad, a cellulosic pad, and a metal foam pad. The results showed that the performance of the cooler is relatively reasonable during the summer. However, its performance can be more improved using high performance cooling pads such as metal foam pads.

A flexible nanobrush pad for the chemical mechanical planarization of Cu/ultra-low-к materials

A new idea of polishing pad called flexible nanobrush pad (FNP) has been proposed for the low down pressure chemical mechanical planarization (CMP) process of Cu/ultra-low-к materials. The FNP was designed with a surface layer of flexible brush-like nanofibers which can ‘actively’ carry nanoscale abrasives in slurry independent of the down pressure. Better planarization performances including high material removal rate, good planarization, good polishing uniformity, and low defectivity are expected in the CMP process under the low down pressure with such kind of pad. The FNP can be made by template-assisted replication or template-based synthesis methods, which will be driven by the development of the preparation technologies for ordered nanostructure arrays. The present work would potentially provide a new solution for the Cu/ultra-low-к CMP process.

Effect of Solder Volume on Interfacial Reaction between Sn-3.0Ag-0.5Cu Solder Balls and the Substrates

Nowadays, with the continuous miniaturization of electronic packages, the solder balls used to join chips and substrates are downsizing. While the decrease in solder size may have a detrimental effect on the reliability of solder joints. In this paper, Sn-3.0Ag-0.5Cu solder balls were reflow soldered on two kinds of pads (Cu and Ni-P) to give a comparative study of the volume effect. Cu/Sn-3.0Ag-0.5Cu and Ni-P/Sn-3.0Ag-0.5Cu joints displayed volume effect of different forms. In the reaction of Cu/Sn-3.0Ag-0.5Cu, scallop-type Cu6Sn5 grains formed at the interface. The grain size and thickness of Cu6Sn5 IMC together with the Cu consumption were influenced by solder volume. In the reaction of Ni-P/Sn-3.0Ag-0.5Cu, different type of interfacial IMCs formed for solder balls with different sizes. Changes of Cu content in solder balls play an important role in both kinds of reactions.

CMP 결과에 영향을 미치는 마찰 특성에 관한 연구

Chemical mechanical polishing (CMP) process was studied in terms of tribology in this paper. CMP performed by the down force and the relative motion of pad and wafer with slurry is typically tribological system composed of friction, wear and lubrication. The piezoelectric quartz sensor for friction force measurement was installed and the friction force was detected during CMP process. Various friction signals were attained and analyzed with the kind of pad, abrasive and abrasive concentration. As a result of experiment, the lubrication regime is classified with ηv/p(η, v and p; the viscosity, relative velocity and pressure). The characteristics of friction and material removal mechanism is also different as a function of the kind of abrasive and the abrasive concentration in slurry. Especially, the material removal per unit distance is directly proportional to the friction force and the non~uniformity has relation to the coefficient of friction.

Study on the characteristics of Magneto-Electrolytic-Abrasive Polishing by using the newly developed nonwoven-abrasive pads

Recently, advanced technologies in general industry demand that the production of precision parts is much more precise and efficient. However, most of the precision finishing technologies cannot satisfy both the finishing efficiency and surface finishing at the same time. Magneto-Electrolytic-Abrasive Polishing (MEAP) is a new ultra precision machining technology, which combined many kinds of energy, has been deeply investigated under this urgent demand and its effect has been much improved. The method of MEAP for those difficult-to-cut materials has become an important technique in the precision machining field. In particular, the nonwoven abrasive pad, which is a kind efficient matching polishing material used in MEAP system, has been developed. Because nonwoven abrasive pads can cut off the oxide membrane which appears during electrolytic polishing process without time delay and there are no scratches left on workpiece surface, it has been proved that it is a high efficiency and economic polishing material. In this study, the basic properties of nonwoven abrasive pads have been explained and the developed processes for SiC and Al 2O 3 nonwoven abrasive pads have also been described. Their polishing abilities on difficult-to-cut materials of Cr-coated rollers have been tested according to different kinds of pad. Through using the life test experiment, their economic benefits in Magneto-Electrolytic-Abrasive Polishing systems will be discussed.