• The Journal of Engineering Geology
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• v.4 no.1
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• pp.43-55
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• 1994

Two thematic maps on environmental geology were produced in the Cheong-Ju area, with aids of GIS technique. They are landslide hazards & risk maps and cut-fill maps. The models of environmental geology map and digital database were established for creation of these maps by means of cartographic simulation in GIS. These special maps are very important for understanding the environmental characteristics of the study area, and can be applied in the establishment of the regional land use planning. For instance, the landslide hazard and risk map can play very important role in the road design, and cut- fill map in the construction work in the area. The scoring system for landslide analysis was developed through the evaluation of each environmental geologic factor in relation to the others and reflects the relative imporatance of each factor. The excavation index(easy, intermediate and difficult) was evaluated through cut-fill analysis, and they can be very useftil for assessing the degree of excavation difficulty.

• Korean Journal of Oriental Medicine
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• v.12 no.3 s.18
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• pp.117-130
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• 2006

The purpose of this study was to introduce the differential standard of Mok-Hyaeng Radix species. We established the classificatory standard according to the external and internal morphology and the pattern in 4 kinds of Mok-Hyaeng Radix. The results follow: 1. On the external morphology, Radix of Vladimiria souliei had a sticky material in the head of roots and it was yellowish white in the cut surface. It attached to teeth during chewing. Radix of Aucklandia lappa (=Saussurea lappa) was dark grayish brown and was grayish brown in the cut surface. It had special odor and was not attache to teeth chewing it. On the other hand, Radix of Inula helenium was dark brown. In the cut surface, cortical layer was different from wood layer. Radix of Aristolochia contorta was yellowish brown. In the cut surface, it was not smooth and cortical layer was different from wood layer. 2. On the internal morphology, Radix of Vladimiria souliei had many fascicular fibers and scattered large oil chambers in the bast ray, xylem ray, and parenchyma. On Radix of Aucklandia lappa (=Saussurea lappa), it was difficult to find out the trace when the cork layer was exfoliated. The cambium formed circle and the large oil chambers were scattered in the phloem and xylem. On the other hand, external cortical layer of Radix of Inula helenium was detached and cambium was formed to indistinct circle and large oil chambers were scattered in the phloem and xylem. On Radix of Arustolochia contorta, the large oil chambers were scattered in the surface later, bast part was relatively broad and cambium formed circle. 3. On the TLC pattern, Radix of Aristolochia contorta, Inula helenium, Aucklandia lappa, and Vladimiria souliei were chromogenic to violet and purple according to sulfuric acid colour pattern, especially faint on Aristolochia contorta. 4. On the pattern analysis of HPLC, we compared the content and the pattern of constunolide and dehydrocostus lactone, Radix of Aucklandia lappa was similar to Radix of Vladimiria souliei and Radix of Aristolochia contorta was similar to Radix of Inula helenium. On the total HPLC component pattern, constunolide and dehydrocostus lactone were similar in all four types, but it showed the Rf 5-6 peak was only in Radix of Aristolochia contorta, not in Radix of Inula helenium, Aucklandia lappa, and Vladimiria souliei. It is considered the results of this study will be furnished the basis to succeeding studies and it is needed to extensive comparative study for the same genus-degree of relatedness.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.59-64
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• 2002

Recently the applications of high speed machining are increasing due to the need for high performance and high accuracy machining and machining for difficult-to-cut material. However, the high speed machining also accompanies some problems: the product quality can be degraded due to the tool wear and the product cast can go up due to frequent tool replacements. Therefore, it is necessary to develop a technique of quantitative tool wear measurement to determine the precise timing for tool replacement. In this respect, this study suggests a reliable technique far the reduction of error components by developing a system using a CCD camera and an exclusive jig to be able to precisely measure the size of tool wear in flat end mill for high speed machining.

• Journal of the Korea Furniture Society
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• v.12 no.1
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• pp.125-130
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• 2001

The sofa industry, which is now one of the major furniture industries in Korea, has developed since 1970s as the apartment building boom and the rise of living standards triggered its demand. Among others, durable and high-quality leather sofa had been most favored and excelled other sofas since mid-1980s along with the growth of national economy before IMF control tightened money market in late 1990s. Leather sofa is still favored and its industry has great possibilities to increase as people tend to seek higher and more personalized living conditions with the stabilization of economy. However, there are several problems in the sofa industry due to the current economic difficult conditions, i.e.; 1. It is hard to cut down the cost of raw material as the supply mostly depend on import. 2. It is hard to keep product quality due to technical difficulties. 3. There are still illegal duplicates of foreign or domestic competitors'design. The aim of this study is to examine the reality of the leather sofa industry in Korea and to suggest new vision for its progress.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.977-981
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• 2004

Variety of recent railroad markets arouses the need for steel sleepers. Steel sleepers have many advantages over conventional timber or PC sleepers with respect to safety, environment and economical efficiency due to less effort for maintenance. Weak points of timber sleepers are to cut trees and apply toxic creosote as well as to need frequent maintenances while it is difficult to apply PC sleepers to steel bridge or crossing and to recycle them completely. In this paper, technical trends are analyzed in order to develop suitable steel sleepers for domestic railroads.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.866-869
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• 2000

To improve quality of the ground surface, we have to consider a number of parameters. But it is difficult to make experiment with many parameters. Most of all experiments try to search optimal grinding condition with conservative factors such as feed rate, depth of cut, wheel rotating speed, etc. But This paper attempts to view the significance of some different factors effecting on the surface roughness by introducing helical scan grinding method and material removal rate. The design of experiment is used to find the optimal grinding condition which minimizes the surface roughness value bout optical glass material. To analyze experimental results, ANOVA(ANalysis of VAriation) is used. Discussion on the result about helical scan grinding is also given.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.13 no.22
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• pp.79-85
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• 1990

An important problem to be carried into a plan on the occasion for introduction of TQC is to establish the clear-cut policy and workable system on QC. In connection with escalation the product liability in recent days, especially, a point to he considered in relation the real state of enterprise, it seems likely to be difficult an effective performance without distribution of the definite duality function to each departments in the company, and to define the quality function, it should be educed and coordinated under agreement organization wide participation and conciliation. In this paper, we have tried to have a more effective graft the European style QC on the oriental enterprise, by means of presenting a model that manages synthetically a way of deployment the fundamental factors affecting quality, and establishing the control subject in each function unit.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.2
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• pp.46-49
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• 2005

Recently, many research results have been reported about nano-tip using carbon nanotube because of its better sensing ability compared to a conventional silicon tip. However, it is very difficult to identify the carbon nanotube having proper length for nano-tip and to attach it on a conventional tip. In this paper, a new method is proposed to make a nano-tip and to control its length. The electrochemical etching method was used to control the length by cutting the carbon nanotube of arbitrary length and it was possible to monitor the process through current measurement. The etched volume of carbon nanotube was determined by the amount of applied charge. The carbon nanotube was successfully cut and could be used in the nanogripper.

• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.117-125
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• 2001

Polyacetal resin is usually used to make molds, but it is difficult to achieve dimension accuracy during molding. Therefore it is usually necessary to cut the polyacetal resin after a molding process. Polyacetal resin is easily machining by standard machine tool. Acetal is also a thermal stable material which can be totted without coolant Another concern about the use of polyacetal resin is that it absorbs water easily, which also results in problems with dimension accuracy Therefore, in this study, the cutting resistance of water-absorbed polyacetal resin and its surface roughness after cutting in order to achieve the highest degree of accuracy in the cutting of polyacetal resin were investigated. Also, The Robust Design method uses a mathematical tool called orthogonal arrays to study a large number of decision variables with a small number of experiments. It also uses a new measure of quality, called signal-to-noise (S/N) ratio, to predict the quality from the customer's perspective. Thus, we have taken Taguchi's parameter design approach, specifically orthogonal array, and determined the optimal levels of the selected variables through analysis of the experimental results using S/N ratio.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.159-167
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• 1999

For exisiting $K_0$-oedometer, the lateral wall of the ring is cut thinly to make space and by filling the space with space with water or mercuty to keep the balance to the lateral pressure of a specimen, the pressure of the fluid is checked for the pressure of the specimen. But the devices to keep the balance to the lateral pressure of a specimen are complicated, difficult to manufacture and expensive. As newly developed $K_0$-oedometer is equipped with the load cell which can resist higher pressute than the lateral pressure of the specimen, there is nearly no deformation due to the lateral pressure of the specimen. And the measuting is cheap and easy as there are fewer accessories.