• Journal of Korean society of Dental Hygiene
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• v.3 no.2
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• pp.197-208
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• 2003

This study was implemented for 84 students of dental hygiene to show the correlation between dental caries experience and improved caries activity test. Dental caries experience for the sample groups was examined and stimulative saliva secreted for 5 minutes was collected into the tube to check saliva secretion rate. Dentocult LB test was executed to observe Lactobacilli colonies after 96 hour cultivation of culture slides moistened with stimulative saliva. Dentocult SM test(screening strip, site strip) was done to measure SM colonies distribution after 48 hour cultivation of culture strips applied with collected saliva and dental plaque respectively, and salivary buffering capacity was checked by means of Dentobuff strip kit. Following conclusions are obtained after examining the relation between Dentocult LB, Dentocult SM, Dentobuff strip test results and DMFT index, salivary secretion rate. 1. Showed no significant difference between Dentocult LB test results and DMFT index, salivary secretion rate. 2. Showed no significant difference between Dentocult SM(screening strip) test results and DMFT index, salivary secretion rate. 3. Showed significant difference between Dentocult SM(site strip) test results and DMFT index(pE0.05), but showed no significant difference between Dentocult SM(site strip) test results and salivary secretion rate. 4. Showed no significant difference between Dentobuff strip test results and DMFT index, but showed a very wide difference between Dentobuff strip test results and salivary secretion rate(pE0.01).

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.212-212
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• 2000

This study was performed to construct a hot strip speed measuring system and check over whether the measured speed can be used for improving the mass flow of the head-end part of a hot strip in the 7-stand finishing mill. Because the mass flow in hot rolling mill affects the looper operation and the thickness and width control of a strip, accurate measurement of strip speed ie important. The measured speed was compared with the roll speeds of No. 6 and No.7 stand to check the performance of the system and analyzed to find how to apply the speed. As a result, it is shown that the accuracy of the system is enough, strip thickness error can be reduced by -275∼+200$\mu\textrm{m}$ using the measured speed and the existing FSU model has low accuracy for predicting forward slip rate. A neural network was developed to calculate forward slip rate instead of FSU model. The test result of the neural network shows that the neural network is more accurate than the FSU model.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.95-101
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• 2008

The wind speed reduction capability of forest belt of Caragana Korshinskili Kom in Yanchi, Ningxia province in China is as follows. 1. At the height of 0.5 m, the windbreak effect is 3-Strip (30.22%) > 2-Strip (26.53%) > 1-Strip (16.28%) from 1H (H = Tree Height) to 5H, and the windbreak effect is 2-Strip (16.11%) > 3-Strip (12.79%) > 1-Strip (9.82%) for greater than 7H. Further analysis of 2-Strip and 3-Strip revealed that the wind reduction effect of 2-Strip spread to 44H and 3-Strip spread to 27H. This result implies that 3-Strip is most effective for short distances and 2-Strip is most effective for long distances. 2. At the height of 1.0m, the wind speed was relatively constant and the reduction rate of wind speed had a minimal variation, with the reduction rate of 1-Strip (8.04%), 2-Strip (8.23%), and 3-Strip (7.43%). 3. The sandbreak effect is 2-Strip (55.28%) > 3-Strip (37.13%) > 1-Strip (20.87%). Especially, The rate of sandbreak of 1H (86.06%) of 2-Strip is most effective value in whole data.

• Journal of computational fluids engineering
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• v.19 no.1
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• pp.34-40
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• 2014

Conjugate heat transfer of an automotive oil cooler with offset-strip fins was numerically investigated to predict the performance of the oil cooler for various flow-rates. The simulations were conducted by directly modeling offset-strip fins with unstructured meshes. The incompressible Navier-Stokes equations coupled with energy equation were used for the present simulations. Heat transfer characteristics of the oil cooler was compared well with experimental results and the errors were approximately within 5 percents. It was found that the performance of the oil cooler increased as the flow-rate increased up to the flow-rate of 12 L/min, but the performance seemed to be saturated beyond a critical flow-rate, which was estimated as 15 L/min. Furthermore, it was confirmed that compared to the performance without fins, that of the oil cooler with offset-strip fins was increased by about 75 percents.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.1 s.232
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• pp.16-26
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• 2005

Air-cooled heat sinks are employed in many electronic cooling applications since they provide significant heat transfer enhancement and operational flexibility. Strip-shaped fin heat sink is of interest and needs to be investigated as general cooling products for more applicability. The purposes of this study are to evaluate heat sink performance without bypass flow condition and to determine optimal heat sink geometries. The results show that the decreasing rate of thermal resistance of a heat sink decreases with increasing inlet air velocity, and the increasing rate of pressure drop increases with increasing inlet air velocity, but is not affected by input power. The increasing rate of optimal longitudinal fin spacing is larger than that of transverse fin spacing. The strip fin heat sink tested in this study showed better cooling performance compared to that of other plate fin type.matism. 2004; 50(11): 3504-3515.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.12
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• pp.591-596
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• 2006

we have been developed on the ultra high concentration ozone generator system which is the core technology in the realization of the semiconductor photoresist strip process using the ozone-vapor chemistry. The proposed ozone generator system has the structure of the surface discharge type which adopt the high purity ceramic dielectric tube. We investigate the performance of the proposed ozone generator system experimentally and the results show that the system has very high ozone concentration characteristics of $19.7[wt%/O_2]$ at the flow rate of $0.3[{\ell}/min]$ of each discharge cell. As a result of the silicon wafer photoresist strip test, we obtained the strip rate of about 400[nm/min] at the ozone concentration of $16[wt%/O_2]$ and flow rate of $8[{\ell}/min]$. So, we confirmed that it's possible to use the proposed high concentration ozone generator system for the ozone-vapor photoresist strip process in the semiconductor and FPD industry.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.544-548
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• 2008

At the semiconductor industry, Photoresist(PR) strip progress has high cost and time consuming process. Accordingly, many research group have been focused on the shortening of the PR strip progress. But the replacements of newly developed materials rather than normally used strip have accompanied by cost consumption. Therefore, we suggested the Plasma Liquid-Vapor Activation (PLVA) method of general PR strip solution for saving the PR strip time and the high strip rate of PR residue. The PLVA method was very effective for PR strip progress. Also, the ion damaged PR(high dose implanted photoresist: HDI-PR) was almost impossible to strip. However, it was very difficult to characterize the change of chemical composition of HDI-PR between with and without PLVA method. Thus, physical properties of HDI-PR surface with and without PLVA method were measured by using the nano-indenter system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.10
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• pp.1392-1399
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• 2001

The flow fields inside a molten Zn pot of continuous hot-chip galvanizing process were investigated experimentally. With varying several parameters including the strip speed Vs, flow rate Q of induction heater. scrapper location and baffle configuration, instantaneous velocity fields were measured using a PIV velocity field measurement technique. Inside the strip region, counter-clockwise rotating flow is dominant. The general flow pattern inside the strip region is nearly not influenced by the strip speed Vs, flow rate Q and the scrapper location. In the exit region, the flow separated from the moving strip due to the existence of a stabilizing roll ascends to the free surface, for the cases of no scrapper and scrapper detached form the roll. On the other hand, the ascending flow to the free surface is decreased, as the flow rate Q of induction heater increases. By installing a baffle around the uprising strip, the flow moving up to the stabilizing roll decreases. In addition, B-type baffle is better than A-type baffle in reducing speed of flow around the stabilizing rolls. However, the flow ascended to the free surface is largely influenced by changing the flow rate Q, and the scrapper location, irrespective of the baffle type.

• Journal of Mechanical Science and Technology
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• v.17 no.6
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• pp.854-859
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• 2003

In this paper, we examine the singular stresses and electric fields in a functionally graded piezoelectric ceramic strip containing an eccentric crack off the center line under anti-plane shear loading with the theory of linear piezoelectricity. It is assumed that the properties of the functionally graded piezoelectric ceramic strip vary continuously along the thickness. Fourier transforms are used to reduce the problem to the solution of two pairs of dual integral equations, which are then expressed to a Fredholm integral equation of the second kind. Numerical values on the stress intensity factor and the energy release rate are obtained.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.1
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• pp.22-27
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• 2007

we have been studied on the realization of the boundary layer controlled ozone process and related facilities in order to apply for the photo-resist strip process in the semiconductor and flat panel display manufacturing. By means of developing the technology for the high concentration ozone production, it was possible to realized the boundary layer control ozone process by vapor. As a result of the silicon wafer PR strip test, we obtained the strip rate of about 400nm/min at the ozone concentration of 16wt% and flow rate of 8[liter/min.].