• Korean Journal of Materials Research
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• v.32 no.7
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• pp.326-331
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• 2022

AZ31 magnesium alloy was used to manufacture a thin plate using a melt drag method. The effects of roll speed, molten metal temperature, and molten metal height, which are the basic factors of the melt drag method, on the surface shape, the thickness of the thin plate, Vickers hardness, and microstructure of the thin plate were investigated. It was possible to manufacture AZ31 magnesium alloy thin plate at the roll speed range of 1 to 90 m/min. The thickness of the thin plate, manufactured while changing only the roll speed, was about 1.8 to 8.8 mm. The shape of the solidified roll surface was affected by two conditions, the roll speed and the molten metal height, and the Vickers hardness of the manufactured magnesium alloy thin plate value ranged from Hv38~Hv60. The microstructure of the thin plate produced by this process was an equiaxed crystal and showed a uniform grain size distribution. The grain size was greatly affected by the contact state between the molten metal and the solidification roll, and the amount of reactive solids and liquids scraped at the same time as the thin plate. The average grain size of the thin plate fabricated in the range of these experimental conditions changed to about 50-300 ㎛.

• Journal of Mechanical Science and Technology
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• v.14 no.1
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• pp.72-83
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• 2000

In recent years considerable progress has been made in the characterisation of surface finish in three dimensions, and in the development of protocols which can be used for international standardisation. Although the subject as it has currently developed has much further to go if the process of surface characterisation is to impact on manufacture, control and specification of the manufacturing process itself. Researchers in this important area are beginning to realise that if the subject is to have great impact on manufacturing industries, surface characterisation must be broadened to include measures of surface integrity of the component and in addition be related to the functional demands imposed on the surface. The functional demands being a requirement of the engineering situation in which the components are employed. If these three factors are considered simultaneously, surface characterisation, surface integrity and component function, then a new and important subject is born, the subject of the Engineered Surface. Part 1 of this paper attempts to draw together the elements which go together to create the subject, 'The Engineered Surface'. The paper presents a method by which this important subject can be developed to the benefit of manufacturing industries. The paper also discusses the importance of a co-ordinated approach to the subject and the way that information can be documented to eventually provide a useful atlas of controlling parameters which are essential for a range of material processing industries as they strive to meet the ever more stringent and cost effective requirements of the manufacture.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.29-37
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• 2020

This research seeks to determine the influence of investment opportunity set (IOS); profitability (Return on Assets - ROA), liquidity, business risk and firm size on debt policy. We used 42 manufacturing companies registered on the Indonesian Stock Exchange (Bursa Efek Indonesia) as object research. We used purposive sampling method to determined samples, consider the period observation from 2012 to 2016, and produce 168 units analysis. Data analysis uses the multiple regressions with the SPSS tools. The results of the study found that companies' debt policies in Indonesia are negatively affected by the liquidity. Investment opportunity set (IOS) has negative effect on debt policy. Meanwhile, ROA, Return on Invested Capital (ROIC), and firm size of a company has no impact on debt policy. These findings indicate that Indonesian manufacture companies do not see the high investment opportunity set and profitability as a policy basis for increasing debt. Moreover, the high profitability also does not cause companies to increase their debt ratio. Our study indicates that Indonesian manufacture companies use internal funds to fund their investment. This finding is a concern for creditors, as they can now see the ability of the companies, and especially their performance, in determining their credit policies.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.124-136
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• 2001

In this paper, we designed and manufactured the Ku-band circular waveguide antenna to do wireless communication with a ground radar as on-board antenna of missile. Using the MATLAB and the HFSS, we designed the circular polarizer which has a characteristic of circular polarization and broadband using the capacitive pin method, the feeder to feed coaxial line to circular waveguide, and a stopper to prevent a conductor material from being inserted. Then we simulated the designed antenna using the HFSS, obtained the gain and the radiation pattern. Because of a difficulty of manufacture, we established a manufacture process procedure. Antenna is manufactured with this procedure, test results of the manufactured antenna are the axial ratio of 1.37 ~ 1.72, the 3 ㏈ beamwidth of $72.23^{\circ}{\sim}78.54^{\circ},$ and the gain of 3.26 ~ 4.61 ㏈ within frequency band. We knew that these results are similar with simulation results. Also, we confirmed that the manufactured antenna is satisfied with requirement conditions through performance test, environmental test and flight test.

• Proceedings of the Korean Society for Quality Management Conference
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• 2006.11a
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• pp.205-210
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• 2006

Nowaday manufacture technology and manufacture environment are changing rapidly. By development of computer and enlargement of technique, most of manufacture field are computerized. It is measured automatically do much quality characteristics thereby and great many data happen in a day. corporations is important if have gotten fast information that are useful from wide data to go first in international competition according to these change. Statistical process control(SPC) techniques are used as a problem solution tool at manufacturing process until present. However, this statistical methods is not applied more extensively because have much restrictions in realistic problem. In this paper, wish to develop more realistic and scientific new statistical design techniques doing to integrate data mining(DM) and statistical methods by the alternative to cope these problem. First step selects significant factor using DM techniques from datas of manufacturing process including much factors and second step wish to find optimum of process after get the estimated response function through response surf ace methodology(RSM) that is statistical techniques.

• Journal of Korean Society for Quality Management
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• v.34 no.4
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• pp.33-39
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• 2006

These days manufacture technology and manufacture environment are changing rapidly. By development of computer and enlargement of technique, most of manufacture field are computerized. In order to win international competition, it is important for companies how fast get the useful information from vast data. Statistical process control(SPC) techniques have been used as a problem solution tool at manufacturing process until present. However, these statistical methods are not applied more extensively because it has much restrictions in realistic problems. These statistical techniques have lots of problems when much data and factors are analyzed. In this paper, we proposed more practical and efficient a new statistical design technique which integrated data mining (DM) and statistical methods as alternative of problems. First step is selecting significant factor using DM feature selection algorithm from data of manufacturing process including many factors. Second step is finding optimum of process after estimating response function through response surface methodology(RSM) that is a statistical techniques

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.139-146
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• 2015

We manufactured natural dyed Korean traditional paper (Hanji) for cultural properties conservation and storage with goldthread (Coptis chinensis) and silver nitrate ($AgNO_3$). Goldthread and silver nitrate are known to be an excellent antimicrobial activity. The effect of content of goldthread and silver nitrate on properties of dyed Hanji was investigated. Color strength of dyed Hanji decreased with increasing content of silver nitrate. After-mordanting with 3% silver nitrate improved lightfastness of dyed Hanji. Tannic acid treatment increased K/S value of dyed Hanji. As the amount of the increase in goldthread content was reduced silver nitrate content. Sim-mordanting method was used for simplifying manufacture process. Silver nitrate sim-mordanting method increased K/S value of goldthread than after-mordanting method.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.855-859
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• 2009

In this paper, we introduce the estimation method by Risk or SIL(Safety Integrity Level) for the criterion of safety assurance and summarize each application method and target. IEC 62278(EN 50126) which is international standard for the specification and verification of the railway system RAMS indicate a criterion of safety assurance. Especially, it recommend the safety verification by continuous verification as the order of requirement establishment, design, manufacture, installation, operation, and maintenance for the equipment not easy to quantify the operation environment. In this paper, we study the SIL requirement allocation method relating to internal new system development and existing system improvement by analysing SIL recommendations which were used to understand SIL for a train control equipment in 1990s in IRSE and theoretically their allocation background. This paper help the safety management of Korea train control system to develope the quantitative management procedure as international level by analyzing the SIL requirement allocation by operation agency and the right SIL verification procedure by manufacture and indicating the example to assure safety because it is necessary for improvement and localization for the Korea train control system having highly dependence on aboard technology.

• Journal of the Korean Magnetics Society
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• v.11 no.1
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• pp.1-7
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• 2001

We investigated to DC magnetic characteristics, the dependence of annealing temperature on the crystal grain and the crystalline orientation for grain-oriented silicon ribbon with 100 $\mu\textrm{m}$ final thickness manufactured by three times cold rolling method using the hot-rolled silicon steel plate as a raw material. The growth of (110)[001] Goss texture were almost observed in the whole area of the sample. The values of the saturation magnetic flux density B$\sub$s/ and the average ${\alpha}$ angle have 1.9 T and 4.6 degrees respectively. From this result we could be confirmed that the three times cold rolling method has a possibility of manufacture for oriented ultra-thin silicon ribbons much more simple and cheeper than the existing oriented silicon steel manufacturing method by means of more simplified producing process.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.731-739
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• 2006

The text of 'Jeungbosallimgyeongjae' was reviewed to study the manufacture of vinegar and to investigate the changes made to the manufacturing process over time, other works such as 'Eumsigdimibang(1670s)', 'Sallimgyeongjae(1715)', 'Gyuhapchongseo(1815)', 'Juchan(1800년대경)' and 'Chosun-mussangsinsikyorijaebeop(1930)', 'Chosun-eumsikmandeneubeop(1946)' were compared. In both 'Eumsigdimibang', and 'Sallimgyeongjae' there are only three statements on vinegar manufacturing theory. For 'Sallimgyeongjae' these statesments are recorded specifically in the 'Chison' section. This book contains the following topics: the proper number of days for vinegar fermentation vinegar storage theory, how to maintain the vinegar in the pot, and nine vinegar manufacturing theories. 'Gyuhapchongseo' discusses the proper or improper number of days to ferment vinegar, and offers four general theories on vinegar manufacture. 'Ju-Chan' is a book of recipes from the latter era of the Chosun Dynasty. There are three statesments on 'yangchobang' recorded in this book. 'Chosun-mussangsinsikyorijaebeop' contains a general summary on vinegar that includes the theory of vinegar production, the right number of days for fermenting vinegar, clues for maintaining the vinegar in the pot, the method for making vinegar from spoiled alcohol, and finally, how to keep vinegar from molding The book also includes 11 statesments on the theory of vinegar manufacture. In 'Chosun-eumsikmandeneubeop', there are two statesments on vinegar manufacturing theory recorded. To study the use of vinegar in cooking as well as the change in manufacturing theories over time, we selected 'Eumsigdimibang', 'Sallimgyeongjae', 'Gyuhapchongseo', 'Chosun-mussangsinsikyorijaebeop' for a comparative analysis with the book 'Jeungbosallimgyeongje'. From this comparison of the texts we were able to learn the scientific nature of traditional foods. In addition, current vinegar manufacturing practices are changing the originally enjoyed flavors ghat are found with traditional vinegars. By the investigation of historic recipe book 'Ju-Chan,' and given the regular use of vinegar on cooking, we have found the means to reproduce the relished tastes of the past.