수액용기 발전추이 고찰

황영국 (사)한국포장협회 2004 包裝界 Vol.137 No.-

주축 런아웃이 절삭흔과 표면거칠기에 미치는 영향에 관한 연구

황영국,이춘만,임경진,하재용,신성우 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

The radial error motion of a machine tool cutter/spindle system is critical to the dimensional accuracy of the parts to be machined. This paper presents an investigation into spindle run-out effects on cutting mark and surface roughness. We experimented the effects of spindle run-out on surface roughness in flat-end milling by cutting AL 7075 workpiece in various cutting conditions. In order to analyze the effects of run-out on the surface roughness, the spindle's radial error motions was measured by mounting a sphere target onto the spindle as a reference. From the experimental results, it was found that spindle run-out makes a directive effects on surface roughness in flat-end milling.

Liverpool 정부 소고

황영국 慶尙大學校 1995 論文集 Vol.34 No.1

Liverpool's government was unfortunate in having to deal probably the most complex set of problems ever faced by any British gocernment up to that date : ecoomic and social distress, the demand for Cathoric Emancipation in lreland, and widespread disturbances which surgested that Britain might be on the verge of a revorution like in France in 1789. Strong measures were taken to relieve the distress. As a result of this, number of much needed reforms and impovements were introduced, which led thes phase of the government to be described as liberal toryism. The traditional view still accepted by writers such as Derek Beals is that the Tories were reactionary until 1822, when they suddenly became 'liberal' reformers. More recently Several new points have been suggested : J.E.Cookson suggests that the government was net reationary bofore 1822.

잭슨期 産業革命의 性格

黃榮國 慶尙大學校 1984 論文集 Vol.23 No.2

From 183s' to the Civil War, the United States of America was developed its economic situation with a domestic confrontation. After 1820s, the frame of 「American System」 had been established, however, all domestic economic policies were charged in Jacksonian period. After 1830s American industrial revolution was progressed in many ways of conflict, and led already by the cotton industries in New England districts. Though the advocates of the 「american System」 wanted to unify the national products, on the contrast, there was the character of individual and regional in products. On the one hand, realization of Jacksonian Democracy meant a slackness of national unification in products which the party of 「American System」 had mapped up.

Evaluation of Machinability According to the Changes in Machine Tools and Cooling Lubrication Environments and Optimization of Cutting Conditions Using Taguchi Method

황영국,박수현,이춘만 한국정밀공학회 2009 International Journal of Precision Engineering and Vol. No.

This study analyze the effect of machine tools, cooling lubrication environments and cutting conditions on surface roughness and cutting force, and propose the combination of cutting conditions which minimizes the effect of machine tool variables on the dispersion of cutting force and surface roughness by treating the changes in machine tool itself and the installation environments as a noise factors. To do so, the Taguchi method is used to establish an experiment plan, and flat end milling is carried out to measure cutting force and surface roughness. The research results show that in the case of cutting force, the effect of cutting conditions is dominant, and changes in machine tools and cooling lubrication environments barely have effect on cutting force. However, in the case of surface roughness, all of the cutting conditions, machine tool and cooling lubrication environment variables have impact. In order to select a combination of cutting conditions insensible to changes in machine tools, considerations for feed per revolution and axial depth of cut turn out most important in the aspect of cutting force, and considerations for feed per revolution is most important in the surface roughness.

Surface roughness and cutting force prediction in MQL and wet turning process of AISI 1045 using design of experiments

황영국,이춘만 대한기계학회 2010 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.24 No.8

This paper presents an investigation into the MQL (minimum quantity lubrication) and wet turning processes of AISI 1045 work material with the objective of suggesting the experimental model in order to predict the cutting force and surface roughness, to select the optimal cutting parameters, and to analyze the effects of cutting parameters on machinability. Fractional factorial design and central composite design were used for the experiment plan. Cutting force and surface roughness according to cutting parameters were measured through the external cylindrical turning based on the experiment plan. The measured data were analyzed by regression analysis and verification experiments were conducted to confirm the results. From the experimental results and regression analysis, this research project suggested the experimental equations, proposed the optimal cutting parameters, and analyzed the effects of cutting parameters on surface roughness and cutting force in the MQL and wet turning processes.

英國近代市民社會 形成에 있어서 John Locke 思想의 影響 考察

黃榮國 진주산업대학교 1971 論文集 Vol.8 No.-

John Locke is well Known as a philosophical leader of the seventeenth century, and a theoretical advocate of the Glorious Revolution. In this study the Political and economic underpinnings of Locke's thought are traced in their relationship to the historical setting of that time Special attention is devoted to some remarkable limitations of Locke's democratic Ideas. These are ascribed here to the Narrowness of the predominant interest of the victorious class in the age of revolution.

영국의 中産階級과 급진주의 의식

황영국 慶尙大學校 史學會 1997 慶尙史學 Vol.13 No.-

Development of a Variable Preload Spindle by using an Electromagnetic Actuator

황영국,박인황,Kyung-Soo Paik,이춘만 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Variable preload technology involving varying preloads with respect to the spindle speeds and machining conditions is the most suitable preload method for spindles that require extensive rotation. The necessity of variable preload technology will continue to grow as the spindle speed and efficiency increase in order to improve the productivities of machine tools. This study attempts to develop a variable preload spindle that varies the preload with respect to the rotation number, allowing high speed rotation, and improves the stiffness characteristics. The authors designed and fabricated a variable preload device composed of an electromagnetic actuator and other components. We then evaluated the performance of the fabricated variable preload device with an experiment using load cells and subsequently determined the performance of the device and identified areas requiring improvement through a performance evaluation. Finally, we developed a variable preload spindle by applying the produced variable preload device. Smooth operation was verified through performance evaluations of the variable preload spindle, and stiffness improvement was verified through preload variation.

부르크하르트 사관 고찰

黃榮國 진주산업대학교 1978 論文集 Vol.16 No.-

Burckhardt sets up his special view of cultural history through the study of Renaissance. As long as the view of cultural history reaPpear with many sides a mean of nonpolitical history or the past of human, the history of the view of cultural history retraces of Voltaire and other forerunners. But Burckhardt is the best investigator of all others with a great penetration. The substance in Burckhardt's view of cultural history could not deal with the process of time lightly in the history in order to inspect more clearly and lively.