• Proceedings of the Safety Management and Science Conference
• /
• 2009.11a
• /
• pp.231-249
• /
• 2009

The 'Excellent Quality Competitive Enterprises' selection system began with the government's selection and announcement of 'Top 100 Excellent Quality Competitive Enterprises' in 1997 in accordance with Article 6 of the Quality Management and Safety Control of Industrial Products Act and Article 5 (Selection of excellent quality management enterprises, etc.) of the Act's Enforcement Decree. The content of the research and analysis results is summarized as follows: 1. The participation and confidence of enterprises in the differentiation of the assessment system for the excellent quality competitive enterprises selection system is high: from the initial year to the present, 10% of enterprises have participated in the system for over 10 years and since 2000 participating enterprises have been on a steady rise. 2. The distribution of participating enterprises is not limited to any specific region but is spread nationwide, while the participation scale and business types also are being evenly distributed. 3. From the perspective of management performance, as compared with the average of domestic manufacturing businesses or that of U.S. manufacturing businesses, an analysis found that among management results, the excellent quality competitive enterprises achieved far higher sales growth and operating profit rate on sales, however their own capital ratio and debt to equity ratio appeared to be slightly higher.

• Journal of the Semiconductor & Display Technology
• /
• v.11 no.4
• /
• pp.13-18
• /
• 2012

The semiconductor equipments generate a lot of data traffic via communication channels for the effective manufacturing processes of semiconductors and for the automation of semiconductor equipments. These data should be sent to a host computer in order to keep in a safe. The IEEE 802.11e specification gives differentiated and distributed access to a wireless communication medium with four access categories. These four access categories use different priority parameters which lead to quality of service in data traffic. In this paper, it is shown that the throughput of data depends upon the priority parameters provided by IEEE802.11e. We implement the usage of priority parameters in the SECS protocol for semiconductor equipments. It is necessary that the data from semiconductor equipments should be classified with certain priority for the effective use of our proposed method. Therefore, our scheme will contribute to improving the performance of the manufacturing processes of semiconductors.

• Journal of Welding and Joining
• /
• v.31 no.2
• /
• pp.30-36
• /
• 2013

Recently the use of ultra high strength steels(UHSS) in structural and safety component is rapidly increasing in the automotive industry. Furthermore, it commonly use in tailor welded blank laser welding process before hot stamping to reduce lightweight vehicle. However TWB process is to be a problem about welded strength after hot stamping because it's welded before heat treatment. Therefore, in this study, laser welds of TWB after heat treatment were analyzed for changes in the characteristics, especially the impact on the oxidation and decarburization in order to prevent pre-coated Al-Si layer welds on the properties for intensive investigation. As a result, the degradation of the TWB weldments changes in the heat treatment conditions alone, without any pre-treatment of the coating layer has confirmed that there is a limitation on the improvement. Furthermore Al-Si elements are overall distributed on the weldment and it specially concentrated along the fusion line. Hardness value of Al-Si segregation area is less than 350Hv and tensile strength showed just 78~83% compared with substrate. Accordingly, we proved that both side Al-Si coating should be removed in order to ensure the strength of the substrate.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.18 no.6
• /
• pp.585-589
• /
• 2009

Extruder is divided to greatly three part at extrusion process. First, by hopper(Hopper) second, barrel(Barrel) with Screw that is point of extruder and third that is raw material supply wealth extrusion into dies(DIES) Part that decide shape of do product greatly divide. Hopper is role that distribute in raw material supply wealth (Feeding zone) of Screw preserving raw material in state of high quality how at extrusion process, and make distributed raw material as Screw in barrel rotates and 3 stage and inflicting heat and pressure raw material melting(Melting) state. And raw material of melting state Screw's measuring stoker(Metering zone) whereabouts anaphora do and product is completed through pipe channel of dies. Dies that is the most important as Screw in extrusion is part that is last part of melting state process of raw material and causes huge effect in quality of product. If more than design of dies happens, manufacture itself of dies is hard, but there are a lot of amount of losses accordingly. In this research, make pipe channel that raw material of melting state flows in dies can present dies basic design method through flow analysis of ideal pipe channel using CFdesign.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.18 no.5
• /
• pp.483-490
• /
• 2009

The objective of this development project is to localize an automatic molten metal supplier that has been distributed by WESTOMAT, Germany, throughout the world. To achieve this purpose, an energy-saving pressurized dosing furnace and molten metal differential pressure control system that Is able to automatically supply a determined quantity of aluminum molten metal were developed. The localized equipment was installed in a site. Also, the results of the test operation of this equipment can be summarized as follows: It was able to improve the productivity because there were small decreases in supplying speeds and small losses in wastes compared to the existing mechanical molten metal supplier. Also, it was able to minimize the cost in maintenances due to the direct application of high temperature molten metals to molds. In addition, there were small energy losses due to the use of high thermal insulators compared to the existing reverberating furnace and able to prolong the life-time of furnaces and produce good quality nonferrous metals because it represented small carbon refractories and alumina in applied molten metals. Furthermore, it demonstrated no particular differences by objectively comparing it with the product by WESTOMAT.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.18 no.6
• /
• pp.621-628
• /
• 2009

Because the Ultra-Precision Technology increase its competitiveness in the field of the design, precision of processing technology, confidence and fixation degree are major considerations. According to Pattern shapes using these processing technologies, Light Reflection has influence on the sense of sight about human being. Based on background of these studies, we draw a plan about a round workpiece using a 3D design program and analyze the effect on Light Reflection changing a pattern angle and a source of light through SPEOS program in this research. We make Pattern form as V-Shape, and compare the area distributed by Light Reflection by classifying angle into 4 and analyze changes according to a source of light. In order to measure and evaluate the data from simulation analysis we has manufactured Diamond Tool and has processed Pattern precision using a Ultra-Precision Machine. Based on the result of this study, we forecast that the field of design will achieve rapid growth due to Ultra-Precision Technology in the world market.

• Korean Journal of Heritage: History & Science
• /
• v.36
• /
• pp.87-104
• /
• 2003

The Chungdo-type Pottery Culture, distributed through the middle part of the Korean peninsula, is chronologically located in the very former stage of the advent of ancient states. It has two different traditions of pottery manufacturing technique which are totally different in choosing raw materials, shaping, fixing and firing. It seems that two different traditions had been selectively applied by pottery type. In order to understand this peculiar cultural aspect, the pottery typology needs to be different from those applied to cultures where pottery was made and used under the single manufacturing tradition. This study tries to find the new pottery typology which best fits for the understanding the chronology of the Chungdo-Type Pottery Culture. For this purpose, I examined existing typologies, recognized their problems, and then build a new typology. As a result, I found that the former typologies misinterpreted the relative frequencies of each pottery type as different function or region. In this article, I propose the new pottery typology as building a primary classification within each function and region, and then synthesizing all of primary classifications. This new typology eliminates the factors of function and region in understanding the chronology of the Chungdo-Type Pottery Culture, and assorts the regional distinction by comparing pottery types in each region.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.18 no.2
• /
• pp.91-95
• /
• 2019

A new experimental approach is proposed to detect a specific polymer dissolved in a liquid. Distinctive optical properties were found using a laser scattering technique when there is a polymer compound with almost no difference in optical properties (index of refraction) in a liquid phase. The index of refraction, which determines the refraction of light, is obtained by dissolving PCL and PLA. The used samples are biodegradable materials with similar properties and dissolved in a mixture of Chloroform 7: Methanol 3. To predict the optical properties, a 632-nm diode laser was used as the light source of the device, and an integrating sphere was used as the light receiver. Although PCL and PLA had a similar index of refraction of 1.46-1.48, the dissolved PCL showed a relative transmittance of 43%, and the dissolved PLA had a relative transmittance of 34%. The difference in optical properties of the pure polymer compound in the solid state or liquid state is not significantly different, and the difference in the dissolved state in the specific solvent is remarkable because the solubility differs in a specific solution and is randomly distributed.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.6
• /
• pp.15-21
• /
• 2022

This study considered the internal flow considering the internal shape of the CNG filling nozzle, which is widely distributed in Korea. The CNG filling nozzle is the last part to pass through in the CNG filling process and has a significant influence on the filling efficiency. The mechanism was identified by disassembling the CNG filling nozzle and performing a flow analysis according to the mechanism. Consequently, the energy loss owing to eddy currents in the flow was determined, and modeling was proposed to reduce the energy loss by simplifying the shape and parts.

• KIPS Transactions on Software and Data Engineering
• /
• v.7 no.3
• /
• pp.113-120
• /
• 2018

In this study, we proposed a monitoring system for identifying and handling faulty sensing stream data on manufacturing equipments where low-cost sensors can be safely used. Low cost sensors will lessen the cost of implementing distributed monitoring system, but suffer from sensor noises and inaccurate sensed data. Therefore, a distributed monitoring system with low cost sensors should identify faulty signal data as either of sensor fault or machine fault, and filter out faulty signals from sensing fault. To this end, we adopted a fourier transform based diagnostic approach mixed with a weighed moving averaging method, in order to identify faulty signals. We measured how effective our approach is and found out our approach can filter out one-third faulty signals from our experimental environment. In addition, we attached wireless communication modules to reduce sensor and network installation cost. To handle massive sensor data efficiently, we employed unstructured data format with NoSQL based database.