• Journal of Conservation Science
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• v.36 no.6
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• pp.440-455
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• 2020

This study aims to examine the material characteristics of bowls and compare the making techniques of flat cup with cover and jar coffin from the Oryang-dong kiln site, Naju. Bowls, the most frequently excavated small pottery have similar material characteristics, including gray surface, fine-grained texture, and small-sized tempers such as quartz and feldspar, regardless of the excavation slopes. However, the firing temperature of the bowls mostly ranges from 950 to 1,100 ℃. It is estimated that the bowls had formalized making techniques, owing to the similar material composition and firing technique regardless of the excavation slope. The flat cups with cover have similar texture and mineral phases, except their poorly sorted inclusions. However, the jar coffins contain not only fine-grained minerals but also medium-grained quartz, feldspar, and biotite, showing a relatively wide range of firing temperatures. According to the geochemical results of pottery by type, it is assumed that chemical compositions are classified into two groups: small pottery(bowl and falt cup with cover) and jar coffins. In conclusion, small potteries such as bowls and flat cups with cover were made by removing the heavy minerals from raw materials, whereas jar coffins were made by adding medium-grained minerals to raw materials to maintain and support their structures, despite the same source materials. In addition, it is presumed that pottery making proceeded by selecting the source materials, preparing according to their use and controlling the firing temperature and environment.

• Journal of Multimedia Information System
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• v.7 no.2
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• pp.165-174
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• 2020

This document outlines a new color image encryption technology development. After splitting the original image into 240-bit blocks and modifying the first block by an initialization vector, an improved Feistel circuit is applied, sponsored by a genetic crossover operator and then strong chaining between the encrypted block and the next clear block is attached to set up the confusion-diffusion and heighten the avalanche effect, which protects the system from any known attack. Simulations carried out on a large database of color images of different sizes and formats prove the robustness of such a system.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.3
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• pp.233-238
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• 2002

본 논문에서는 유도가열조리기의 효과적인 설계를 위하여 입력주파수 변화에 따른 유도가열조리기의 자계와 열계 해석 방법을 제시하였다. 유도가열조리기의 내부자계는 3차원 축대칭 유한요소법을 사용하여 해석하였으며, 열원은 유도가열조리기의 내부에서 유도된 와전류에 의하여 발생되고, 열은 열원과 열방정식을 사용하여 계산되어진다. 또한, 유도가열조리기의 온도특성을 스테인레스와 알루미늄 각각에 대하여 주파수와 투자율에 따라 제시하였다.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.278-283
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• 2005

Generally Jar-Test is available to determine the coagulant dosage rate. Disadventages associated with Jar-Test are that regular samples have to be taken requiring manual intervention and the limitation to feedback control. To deal with this difficulty, determined optimized dosage rates of coagulant to investigates the union operation method of the statistical equation which uses the multi-regression method and the SCD.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.275-281
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• 2004

Generally Jar-Test is available to determine the coagulant dosage rate. Disadventages associated with Jar-Test are that regular samples have to be taken requiring manual intervention and the limitation to feedback control. To deal with this difficulty, determined optimized dosage rates of coagulant to Investigates the union operation method of the statistical equation which uses the multi-regression method and the SCD.

• Journal of Multimedia Information System
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• v.8 no.2
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• pp.131-142
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• 2021

This paper traces the process of constructing a new one-dimensional chaotic map, and will provide a simple application in color image encryption. The use of Sarkovskii's theorem will make it possible to determine the existence of chaos and restrict all conditions to ensure the existence of this new sequence. In addition, the sensitivity to initial conditions will be proved by Lyapunov's index value. Similarly, the performance of this new chaotic map will be illustrated graphically and compared with other chaotic maps most commonly used in cryptography. Finally, a humble color image encryption application will show the power of this new chaotic map.

• Agrochemical news magazine
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• v.14 no.2 s.113
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• pp.29-31
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• 1993

• Journal of Environmental Health Sciences
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• v.38 no.2
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• pp.128-135
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• 2012

Objectives: This study was aimed at determining the optimum coagulation dosage in a high turbid kaolin water sample using streaming current detection (SCD) as an alternative to the jar test. Methods: SCD is able to optimize coagulant dosing by titration of negatively charged particles. Kaolin particles were used to mimic highly turbid water ranging from 50 to 600 NTU, and polyaluminum chloride (PAC, 17%) was applied as a titrant and coagulant. The coagulation consisted of rapid stirring (5 min at 140 rpm), reduced stirring (20 min at 70 rpm), and settling (60 min). To confirm the coagulation effect, a jar test was also compared with the SCD titration results. Results: SCD titration of kaolin water samples showed that the dose of PAC increased as the pH rose. However, supernatant turbidity less than 1 NTU after coagulation was not achieved for high turbid water by SCD titration. Instead, a conversion factor was used to calculate the optimum PAC dosage for high turbid water by correlating a jar test result with that from an SCD titration. Using this approach, we were able to successfully achieve less than 1 NTU in treated water. Conclusions: For high turbid water influent in a water treatment plant, particularly during summer, the application of SCD control by applying a conversion factor can be more useful than a jar test due to the rapid calculation of coagulation dosage. Also, the interpolation of converted PAC dose could successfully achieve turbidity in the treated water of less than 1 NTU. This result indicates that an SCD system can be effectively used in a water treatment plant even for high turbid water during the rainy season.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.5
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• pp.429-439
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• 2001

EJB(Enterprise JavaBeans), the cornerstone for J2EE(Java$^{TM}$ 2 Platform, Enterprise Edition), is a server-side component standard model. Recently, development of supporting tool for this component model becomes important and there are many tools for developing EJB. In this paper, we purpose to design Enterprise Beans by component model, and perform design and implementation of code generator which generates skeleton code for Enterprise Beans automatically. We also implement EJB deployer for deploying these on application server. The code generator can make a JAR file automatically. This JAR file is deployed on application server by EJB specification as well. Using this tool, developer can create and deploy of Enterprise Beans more fast and exactly.y.

• Journal of the Korean association of regional geographers
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• v.22 no.4
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• pp.843-855
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• 2016

The objective of this study is to find out geomorphological characteristics of historical ruins where people produced and consumed large jar coffins excavated in the Yeongsan river basin using Fluvio-Marine Plains from detailed soil map. For this purpose, we chose the 21 consumption sites. The results are as follows. 21 consumption sites located in the region of upper limit of tidal internal in Yongsan River and tributary rivers. Among these, 18 Consumption sites has high accessibility with Fluvio-marine plains. This means that Consumption remains of Yongsan River basin have been located to area available for distribution from production sites.