• KSTLE International Journal
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• v.1 no.1
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• pp.12-20
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• 2000

Nano-wear and friction of carbon overcoated laser-textured and mechanically-textured computer hard disk were characterised after contact start/stop (CSS) wear test. Various analytical and mechanical testing techniques were employed to study the changes in topography, roughness, chemical elements, mechanical properties and friction characteristics of the coating arising from the contact start/stop wear test These techniques include: the atomic force microscopy (AFM), the continuous nano-indentation test, the nano-scratch test, the time-of-flight secondary ion mass spectroscopy (TOF-SIMS) and the auger electron spectroscopy (AES). It was shown that the surface roughness of the laser-textured (LT) bump and mechanically textured (MT) Bone was reduced approximately am and 7nm, respectively, after the CSS wear test. The elastic modulus and hardness values increased after the CSS test, indicating straining hardening of the top coating layer, A critical load was also identified fer adhesion failure between the magnetic layer and the Ni-P layer, The TOF-SIMS analysis also revealed some reduction in the intensity of C and $C_2$$F_59$, confirming the wear of lubricant elements on the coating surface.

• Journal of Biosystems Engineering
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• v.13 no.2
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• pp.28-37
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• 1988

This study was conducted to construct the soil bin system and associated microcomputer-based data acquisition system which is to be used for the effective evaluation of wheel performance. The soil bin system consists of four main parts; soil bin, carriage drive system, test carriage and soil processing carriage. The test carriage was constructed to measure the five performance parameters of testing wheels; pulling forte, motion resistance, sinkage and rotational speed of test wheel, and speed of test carriage. The test wheel is powered by a hydraulic system up to 8 ps. Soil processing carriage was designed to provide uniform test soil condition across the toil bin, and reproduction of soil conditions found satisfiable. The data acquisition system consists of APPLE II PLUS microcomputer, strain amplifier, I/O interface, A/D converter, digital counter and various transducers. It takes about 0.86 seconds to measure a set of performance parameters and store on the floppy disk simultaneously. Series of experiment showed that this system can be used effectively for evaluating the wheel performance associated with soil.

• Nuclear Engineering and Technology
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• v.46 no.5
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• pp.667-674
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• 2014

One of the largest problems for tokamak devices such as Kazakhstan Tokamak for Material Testing (KTM) is the operation scenarios' development and execution. Operation scenarios may be varied often, so a convenient hardware and software solution is required for scenario management and execution. Dozens of diagnostic and control subsystems with numerous configuration settings may be used in an experiment, so it is required to automate the subsystem configuration process to coordinate changes of the related settings and to prevent errors. Most of the diagnostic and control subsystems software at KTM was unified using an extra software layer, describing the hardware abstraction interface. The experiment sequence was described using a command language. The whole infrastructure was brought together by a universal communication protocol supporting various media, including Ethernet and serial links. The operation sequence execution infrastructure was used at KTM to carry out plasma experiments.

• The Journal of Society for e-Business Studies
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• v.8 no.4
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• pp.53-68
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• 2003

Currently, it is possible to buy almost anything from books(Amazon.com) to airplane tickets(Travelocity.com) using the world wide web. The purpose of this research is to develop a "clean interface" between design and fabrication facilities for the production of custom machined parts through Internet. The current mechanism for production of prototype parts that can be fabricated using standard machine tools like milling machines, requires a process of part description preparation, bidding, contract award, and finally fabrication and delivery of the part. This is a substantially more complex process than buying a book or airplane ticket. In this paper, we try to define the ambiguous part description using XML based data exchange format and to enable e-commerce in this field. The research accomplishments are summarized: 1. Creation of a new format for data exchange of machined prototype parts, 2. Development of a prototype system to illustrate how the XML data can be effectively used to conduct e-Commerce for custom machined parts, 3. Testing of the methodology with a number of parts.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.1
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• pp.22-29
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• 2008

This paper describes the developed results of vision system for the recognition of material management characters, which was included in the billet image. The material management characters, which was marked at the surface of billet, should be recognized before billet moves to the next process. Our vision system for the character recognition includes that CCD camera system which acquire billet image, optical transmission system which transmit captured image to the long distance, input and output system for the interface with existing system and software for the character recognition. We have installed our vision system at the wire rod line of steel & iron plant and tested. Also, we have performed inspection of durability, reliability and recognition rate. Through the testing, we have confirmed that our system have high recognition rate, 98.6%.

• Advances in aircraft and spacecraft science
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• v.7 no.3
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• pp.251-269
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• 2020

Euclid is an optical/near-infrared survey mission of the European Space Agency (ESA) to investigate the nature of dark energy, dark matter and gravity by observing the geometry of the Universe and the formation of structures over cosmological timescales. The Euclid spacecraft mechanical architecture comprises the Payload Module (PLM) and the Service Module (SVM) connected by an interface structure designed to maximize thermal and mechanical decoupling. This paper shortly illustrates the mechanical system of the spacecraft and the mechanical verification philosophy which is based on the Structural and Thermal Model (STM), built at flight standard for structure and thermal qualification and the Proto Flight Model (PFM), used to complete the qualification programme. It will be submitted to a proto-flight test approach and it will be suitable for launch and flight operations. Within the overall verification approach crucial mechanical tests have been successfully performed (2018) on the SVM platform and on the sunshield (SSH) subsystem: the SVM platform static test, the SSH structure modal survey test and the SSH sine vibration qualification test. The paper reports the objectives and the main results of these tests.

• Journal of Powder Materials
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• v.26 no.5
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• pp.369-374
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• 2019

The properties of powder metallurgy products are related to their densities. In the present work, we demonstrate a method to apply artificial neural networks (ANNs) trained on experimental data to predict the bulk density of barium titanates. The density is modeled as a function of pressure, press rate, heating rate, sintering temperature, and soaking time using the ANN method. The model predictions with the training and testing data result in a high coefficient of correlation (R2 = 0.95 and Pearson's r = 0.97) and low average error. Moreover, a graphical user interface for the model is developed on the basis of the transformed weights of the optimally trained model. It facilitates the prediction of an infinite combination of process parameters with reasonable accuracy. Sensitivity analysis performed on the ANN model aids the identification of the impact of process parameters on the density of barium titanates.

• Elastomers and Composites
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• v.54 no.2
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• pp.135-141
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• 2019

Polyphenylene sulfide (PPS) was filled with glass fiber (GF), aramid fiber (AF), and solid lubricants to improve the mechanical properties and wear resistance. The addition of GF effectively enhanced the tensile strength, flexural modulus, and impact strength of PPS, while solid lubricants such as polytetrafluoroethylene (PTFE), molybdenum disulfide ($MoS_2$), and tungsten disulfide ($WS_2$) lowered the friction coefficients of the composites to below 0.3. The ball nut and motor pulley of the electric power steering (EPS) were manufactured using the PPS composites, and feasibility was ascertained thereafter by conducting the durability test. The composites filled with GF and AF showed high mechanical strength, but slip occurred at the interface between the pulley and belt while testing above $50^{\circ}C$. When small amounts of lubricants were added, the slip was no longer detected because of the suppression of friction heat. It is realized that the low friction as well as high mechanical properties is important to ensure the reliability of plastic pulleys.

• BioChip Journal
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• v.12 no.4
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• pp.294-303
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• 2018

Shear stress occurs in flowing liquids, especially at the interface of a flowing liquid and a stationary solid phase. Thus, it occurs inside the artery system of the human body, where it is responsible for a number of biological functions. The shear stress level generally remains less than $70dyne/cm^2$ in the whole circulatory system, but in the stenotic arteries, which are constricted by 95%, a shear stress greater than $1,000dyne/cm^2$ can be reached. Methods of researching the effects of shear stress on cells are of large interest to understand these processes. Here, we show the development of a microfluidic device for generating shear stress gradients. The performance of the shear stress gradient generator was theoretically simulated prior to experiments. Through simple manipulations of the liquid flow, the shape and magnitude of the shear stress gradients can be manipulated. Our microfluidic device consisted of five portions divided by arrays of micropillars. The generated shear stress gradient has five distinct levels at 8.38, 6.55, 4.42, 2.97, and $2.24dyne/cm^2$. Thereafter, an application of the microfluidic device was demonstrated testing the effect of shear stress on human umbilical vein endothelial cells.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.3
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• pp.333-340
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• 2022

Recently, the use of large-capacity secondary batteries for electric vehicles is rapidly increasing, and accordingly, the demand for technologies and equipment for battery reliability evaluation is increasing significantly. The existing short circuit test equipment for evaluating the stability of the existing secondary battery consists of relays, MCs, and switches, so when a large current is energized during a short circuit, contact fusion failures occur frequently, resulting in high equipment maintenance and repair costs. There was a disadvantage that repeated testing was impossible. In this paper, we developed an electronic short circuit test device that realizes stable switching operation when a large-capacity power semiconductor switch is energized with a large current, and applied smart ICT technology to this electronic short circuit stability test system to achieve high speed and high precision through communication with the master. It is expected that the inspection history management system based on data measurement, database format and user interface will be utilized as essential inspection process equipment.