• Title/Summary/Keyword: I-convergence

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Investment and Debt ratio of ICT firms (ICT 기업의 부채수준이 투자활동에 미치는 영향)

  • Chon, Mi-Lim
    • Journal of the Korea Convergence Society
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    • v.6 no.1
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    • pp.103-108
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    • 2015
  • This paper investigate the determinants of investment for a cross-section of firms in emerging market. I examine three factors expected to affect investment: debt ratio, growth rate, and industry. I find that debt ratio and ICT firms are positively associated with investment in emerging market. I also find that ICT firms with high debt ratio have higher net capital expenditures. While the growth rate is unrelated to net capital expenditures. Unlike the evidence from the developed markets, debt ratio has significant and positive impact on investment (net capital expenditures) in the emerging market.

A Study on the Multi Tapping Process Characteristics and Tread Quality under Difference Pitch (피치가 다른 다축 태핑에서의 가공 특성과 품질 평가에 관한 연구)

  • Lee, Jong-Hyung;Yi, Chang-Heon;Kim, Young-Moon;Lee, Sang-Young;Lee, Sang-Joong
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.4
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    • pp.277-283
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    • 2006
  • As the products such as HDD, Notebook, PDA, and Mobile Phone become smaller and thinner, the radius of threads as well as holes for assembling those products become smaller, even down to 1mm. To produce such small holes and thread efficiently, multi tapping is highly necessitated. However the multi tapping characteristics is not well known because its complicated cutting mechanism and thus the quality of the produced holes and threads is not well studied yet. In this paper, experiments have been conducted for small-radius threads using M2 and M2.6 and M3 cold forming tap to investigate multi tapping process using several useful signal such as torque and Z-axis encoder pulse. The surface and profile of the machined threads have been magnified and observed through a SEM.

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A study on new treatment chemical for leather wastewater; I. Development of new organic coagulant (새로운 피혁폐수 처리제에 관한 연구; I. 새로운 유기 응결제의 개발)

  • Jung, Maeng-Joon;Lee, Chul-Jae;Han, Sung-Wook
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.4
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    • pp.323-330
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    • 2006
  • As the interest in environmental pollution resulting from recent industrial development is converging, wastewater treatment problem of dying processing is one of important pending issue. Usually, flow mediation earth and settling pond etc. of processing plant to handle water or wastewater. Mediation is the wastewater that flowed past settling pond than material of heavy particles, water weight colloid particles that big solids are removed but are suspensibility material settlement exclusion impossible. So, we need flocculation and coagulation action to remove materials from this colloid state. For flocculation and coagulation action chemical agents to add back, addition of chemical agents forms floc of could settle size. That is, shorten the sedimentation time and quality of processing water because promoting sedimentation doing to do fines or suspended solids and colloid can materials large size and also, flocculation to annex efficiency of filtration augment. Therefore, I executed this research to prove that improving organic matter and chromaticity of treated water of processing epochally using organic coagulant informed positive ion co-polymerization superior in color wastewater through this research.

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A Study on Revise the Rule of Safety Controllers of Hazardous Substances (위험물 안전관리 제도의 개선에 관한 연구)

  • Park, Kyong-Jin;Shin, Soo-Kyung;Lee, Bong-Woo
    • Journal of the Korean Society of Industry Convergence
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    • v.23 no.3
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    • pp.473-480
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    • 2020
  • In this study, I analyzed problems of safety management system of hazardous substances and proposed improvement measures. By statistics of Korea National Fire Agency it shows that hazardous substances of not less than a designated quantity were 2,180 factorys, 24,732 handling places and 85,218 storing places in 2018. also It has been conformed that Fire accidents break out year after year in factory, etc. so In this study, I analyzed the safety controllers of hazardous substances of the present law and fire statistics. therefore I has been found out the problems that the first, safety controllers' status. the second, There is no laws related design, installation, installation supervision. the third, fire safety inspection. This study will be used a basic data for preventing of extensive hazazardous substances-related accident that is very difficult handling.

COMPLETE CONVERGENCE FOR ARRAY OF ROWWISE DEPENDENT RANDOM VARIABLES

  • Baek, Jong-Il;Park, Sung-Tae
    • Journal of applied mathematics & informatics
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    • v.27 no.3_4
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    • pp.829-842
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    • 2009
  • Let {$X_{ni}|1\;{\le}\;i\;{\le}\;n$, $n\;{\ge}\;1$} be an array of rowwise negatively associated random variables and let $\alpha$ > 1/2, 0 < p < 2 ${\alpha}p\;{\ge}\;1$. In this paper we discuss $n^{{\alpha}p-2}h(n)$ max $_{1\;{\le}\;k{\le}n}\;|\;{\sum}^k_{i=1}\;X_{ni}|/n^{\alpha}\;{\to}\;0$ completely as $n\;{\to}\;{\infty}$ under not necessarily identically distributed with a suitable conditions and h(x) > 0 is a slowly varying function as $x\;{\to}\;{\infty}$. In addition, we obtained that $n^{{\alpha}p-2}h(n)$ max $_{1\;{\le}\;k{\le}n}\;|\;{\sum}^k_{i=1}\;X_{ni}|/n^{\alpha}\;{\to}\;0$ completely as $n\;{\to}\;{\infty}$ if and only if $E|X_{11}|^ph(|X_{11}|^{1/\alpha})\;<\;{\infty}$ and $EX_{11}\;=\;0$ under identically distributed case and some corollaries are obtained.

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A Study on the Effect of Aluminum Alloy on the Crack Growth Behaviour (알루미늄 합금의 균열진전거동에 관한 연구)

  • Lee, Jong-Hyung;Lee, Hyun-Whan;An, Se-Won;Park, Shin-Kyu
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.2
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    • pp.145-151
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    • 2004
  • According to the development of the aircraft industry, the fatigue strength of Aluminum Alloy becomes a great important material, but it seems that we don't understand an effect on the crack growth behaviour very well. This thesis is not only studied about the five kinds of 2017-T3, 2023-T3, 5083-0, 7075-T6, 7N01-T6 among the Aluminum Alloy which are the main materials of the aircraft, but also small or large relations against the fatigue strength of them. The consequence of the research was being progressed the accordance with the order. That is, The order is 2024-T3> 2017-T3> 7N01-T6> 7075-T6> 5083-0. These inclusion came out the acceleration phenomena in the crack growth behaviour among the high ${\Delta}K$ section Nevertheless I figured out their effects were being ignored at the 2b step.

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Particle Size, Morphology and Color Characteristics of C.I. Pigment Red 57:1 : 1. Effect of Synthesis Conditions

  • Seo, Hee Sung;Lee, Hyun Kyung;Yoo, Eui Sang
    • Textile Coloration and Finishing
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    • v.27 no.4
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    • pp.229-244
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    • 2015
  • The effects of synthesis conditions on characteristics of the calcium-azo complex pigment, C.I. Pigment Red 57:1, were studied. It was mainly considered that the industrially required synthesis conditions for lowering electrical conductivity of the pigment solution keeping pigment quality such as particle size and color characteristics. Three parameters were chosen as control factors during the synthesis. The first was the amount of hydrochloric acid added to transform sodium nitrite into nitrous acid. The second was the amount of calcium chloride added to insolubilize the synthesized azo dye. The final factor was pH control during the coupling reaction. The electrical conductivity and pigment aggregate particle size were dependent on the amount of hydrochloric acid and calcium chloride. Higher HCl concentration gave brighter yellowish-red color because of smaller particle aggregate size and narrower size distribution. Amount of charged ions in the synthesis process might affect the "lake" formation resulting different particle aggregate size and color shade.

Particle Size, Morphology and Color Characteristics of C.I. Pigment Red 57:1 : 2. Effect of Salt Milling Process

  • Seo, Hee Sung;Lee, Hyun Kyung;Yoo, Eui Sang
    • Textile Coloration and Finishing
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    • v.27 no.4
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    • pp.245-260
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    • 2015
  • The effect of salt milling process on the crystal size, morphology, and color characteristics of C.I. Pigment Red 57:1 was studied. The primitive morphology and color properties of the pigment after synthesis were studied in the former series work. The size and morphology of primary particles and the second aggregation features should be considered because they are very important to determine pigment quality. We compared the primary morphology of pigment particles before drying with the secondary aggregated morphology of pigment particles after drying and salt milling process. Morphological properties were investigated by particle size analysis, X-ray diffraction, and scanning electron microscopy and color measurement was carried out. Significant reduction in particle size as well as enhanced crystallite size after salt milling process was observed. This result might give a difference in color of the pigment, turning into brighter and more blue-toned red color. It was revealed that synthesis condition affect the morphology and color of the pigment even after milling. Increase in HCl concentration in the synthesis process enhanced crystal size and quality forming bluer-red pigments but an increase in $CaCl_2$ concentration resulted in more amorphous crystals forming darker-red pigments after salt milling.

A Study on Green Drive control for fuel consumption reduction of the vehicle based on traffic information at the bottleneck (차량의 연료 소비 감소를 위한 병목 도로에서 도로 교통 정보 기반 Green Drive 제어에 관한 연구)

  • Cho, Dae-Hyun;Lee, Chung-Hoon;Lim, Myung-Seob
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.3
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    • pp.162-165
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    • 2012
  • In this paper, the method of controlling velocity between joining vehicles at the point of bottleneck using information and communications technology of WAVE method based V2V and V2I are proposed for the driving with high fuel efficiency. Using the derived fuel-efficiency comparative analysis model, it was shown that the proposed method's fuel efficiency is better than traffic light method demanding periodically vehicle's stop. Also, this method provides the derivation algorithm for deceleration and acceleration for controlling velocity between vehicles approaching bottleneck area.

A Study on Certificate-based Personal Authentification System for Preventing Private Information Leakage through Internet (개인정보 유출 피해 방지를 위한 공인인증서 기반 인터넷 개인인증체계 개선 모델에 관한 연구)

  • Lee, Jung-Hyun;Kwon, Hun-Young;Lim, Jong-In
    • Convergence Security Journal
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    • v.10 no.4
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    • pp.1-11
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    • 2010
  • Recently, We have many private information leakage cases through internet which cause social problems and it is impossible to change or update the leaked information, it is also used to the third crime such as identity theft, internet fraud. Hackers are interested in stealing private information for making money, in this point private information leakage problems are constantly increased hereafter. In this paper, I surveyed the authorization model on site registration which is currently used in Korea, and the problem of collecting personal identification number, I proposed policy model of useless method of private information, especially leaked information can not be used anymore in internet.