• Title/Summary/Keyword: Intensity Distribution

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Electroplating process for the chip component external electrode

  • Lee, Jun-Ho
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2000.11a
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    • pp.1-2
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    • 2000
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the onventional rotating barrel, vibrational barrel(vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components. The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed thatbthe average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value. Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components. However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. 2H20 + e $\rightarrow$M/TEX> 20H + H2.. Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure there by resulting to bad plating condition.

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A Study on the Trade Structure between Korea and RCEP Participating Countries (한국과 RCEP 참여국가와의 무역구조에 관한 연구)

  • Kim, Min-Soo
    • The Journal of Industrial Distribution & Business
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    • v.9 no.1
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    • pp.89-97
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    • 2018
  • Purpose - The Regional Comprehensive Economic Partnership (RCEP) among 16 countries including South Korea, the largest free trade agreement in the Asia-Pacific region, will be concluded next year. The participating countries decided to pursue a comprehensive and high -quality agreement, while ensuring flexibility considering development level of each country. In this study, trade structures between nations from 2005 through 2016 were examined to see the impact that this agreement will have on Korea and to come up with effective countermeasures. Research design, data, and methodology - The method of analysis includes the analysis of the trade matrix, which is useful for identifying the dependency of the individual countries on the market in the region and the reciprocal dependency of the member countries on the market, and the index of intensity of trade, which is useful for figuring out the share of trade between the parties in total trade. Results - The results showed that first, the international trade coefficients of Vietnam and Philippines are higher than those of China and Japan. Secondly, the international inducement coefficients between China and Japan were high, and that between Indonesia and Burma were low, indicating that Korea's exports did not have much effect on export increase of these countries. Third, as a result of analyzing Korea's trade intensity, it was found that export intensity and import intensity were greater than 1 in Vietnam and Philippines, which shows that there is a high degree of relational bond with these countries. India and Laos countries still have a low level of relational bond, which indicates that there is room for improvement in economic relations when the agreement is concluded. After the signing of the agreement in the future, more diverse industrial structures should be continuously studied. Conclusions - The analysis of trade matrix, trade structure, trade inducement coefficient and trade intensity between Korea and RCEP participating countries shows that the majority of the countries have the high level of economic relationship with Korea. Korea should drive a harder bargain when negotiating the terms of the RCEP, in comparison with the level of the existing FTA agreement excluding Japan.

Comparative Analysis of the Competitiveness of the Steel Distribution Industry in Korea and China (한중간 철강유통산업의 경쟁력 비교분석)

  • Lee, Jae-Sung;Jung, Myung-Hee
    • Journal of Distribution Science
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    • v.12 no.6
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    • pp.21-29
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    • 2014
  • Purpose - This research undertakes to understand the competitiveness of the steel distribution industry of both Korea and China to strengthen Korea-Sino economic cooperation, examines impediments to trade between the two countries to analyze causes which affect trade, and examines improvements in these areas to identify means of trade expansion. Through this survey of a defined period, we can identify the structural factors of trade dependence in the relationship between Korea and China. Research design, data, and methodology - The data were collected from the Korea Traders Association, the Korea Customs Office, and UN Comtrade, from which whole table indexes are calculated. The research methodology uses trade-related indexes to focus on analyzing comparative advantages based on time-series analysis statistics data (2000-2012) by using the analysis index of trade intensity index (TII), the revealed comparative advantage index (RCA), and the trade specialization index (TSI). Results - The export ratio for Korea to China was slightly higher in 2000 at 2.867, and the export ratio for Korea to China was sustained in 2005. However, it diminished gradually, reaching 1.263 in 2012. During the period 2000-2012, the indexes were maintained without any significant change. However, they still remain close to -1. In particular, in 2012 it is the closest it has ever been to -1. Therefore, China has a comparative advantage in export specialization. On the other hand, Korea has a comparative advantage in import specialization. For the research period, all indexes were much lower than 1, which means that Korea has consistently had a comparative disadvantage against China for the past 10 years when compared to other industries, even though it experienced improvement in 2000. Conclusions - The summary of conclusions based on empirical analysis research are as follows: First, per the trade intensity index of industries between the two countries, we conclude that the export ratio index in 2000 is 2.867, which means the export ratio of Korea to China is slightly higher. Furthermore, the ratios of 2.259 and 1.263 held in 2005 and 2012, respectively, meaning that the export ratio of Korea to China was maintained in 2005, but was diminishing gradually as the index in 2012 was 1.263. Second, per the trade specialization index of the steel distribution industry between Korea and China, the value was -0.379 in 2000, -0.368 in 2005 and -0.568 in 2012. Looking at the whole period of 2000-2012, the indexes remained without any significant change. However, they are still moving closer to -1. In particular, in 2012 it is the closest it has ever been to -1. Third, regarding the revealed comparative advantage index of the steel distribution industry between Korea and China, the RCA indexes in 2005 and 2012 are 0.246 and 0.306, respectively, which are still far from 1, even though the index has improved compared to the 2000's value of 0.0001. Therefore, the Korean steel distribution industry is at a significant comparative disadvantage to that of the Chinese steel distribution industry.

Determination of Probable Rainfall Intensity Formulas for Designing Storm Sewer Systems at Incheon District (우수거 설계를 위한 인천지방에서의 확률강우강도식의 산정)

  • Ahn, Tae-Jin;Kim, Kyung-Sub
    • Journal of Korean Society of Water and Wastewater
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    • v.12 no.3
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    • pp.99-106
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    • 1998
  • This paper presents a procedure for determining the design rainfall depth and the design rainfall intensity at Incheon city area in Korea. In this study the eight probability distributions are considered to estimate the probable rainfall depths for 11 different durations. The Kolmogorov - Smirnov test and the Chi-square test are adopted to test each distribution. The probable rainfall intensity formulas are then determined by i) the least squares (LS) method, ii) the least median squares (LMS) method, iii) the reweighted least squares method based on the LMS (RLS), and iv) the constrained regression (CR) model. The Talbot, the Sherman, the Japanese, and the Unified type are considered to determine the best type for the Incheon station. The root mean squared (RMS) errors are computed to test the formulas derived by four methods. It is found that the Unified type is the most reliable and that all methods presented herein are acceptable for determining the coefficients of rainfall intensity formulas from an engineering point of view.

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The Regional Rainfall Intensity Formula Development Considering Climate Change of Gimhae City (기후변화를 고려한 김해시의 지역별 확률강우강도식 개발)

  • Woo, Sun-Bong;Park, Jong-Kil;Choi, Sun-Ho;Yoon, Jong-Sung
    • Journal of Environmental Science International
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    • v.23 no.11
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    • pp.1775-1790
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    • 2014
  • The regional rainfall intensity formula for Gimhae in Gyeongsangnam-do province is developed in this study. The nine points of rainfall observations were selected. In order to demonstrate the accuracy and the versatility of the proposed rainfall intensity formula, three regions under the jurisdiction of the Meteorological Agency near Gimhae, namely Busan, Changwon, Miryang observatories were selected. The present formula can be effectively employed for various design of hydraulic structures in Gimhae area since it is divided into several refined regions.

Image Contrast Enhancement Based on a Multi-Cue Histogram

  • Lee, Sung-Ho;Zhang, Dongni;Ko, Sung-Jea
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.5
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    • pp.349-353
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    • 2015
  • The conventional intensity histogram does not indicate edge information, which is important in the perception of image contrast. In this paper, we propose a multi-cue histogram (MCH) to represent a collaborative distribution of both the intensity and the edges of an image. Based on the MCH, if the intensity values have high frequency and a large gradient magnitude, they are spread into a larger dynamic range. Otherwise, the intensity values are not strongly stretched. As a result, image details, such as edges and textures, can be enhanced while artifacts and noise can be prevented, as demonstrated in the experimental results.

An Experimental Study on Turbulent Flow in 90 Degree Bend by using PIV Techiqure (PIV기법을 이용한 $90^{\circ}$ 곡관에서 난류유동에 관한 실험적 연구)

  • 장태현;이해수
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.5
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    • pp.648-656
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    • 2003
  • An experimental research was performed to study turbulent flow characteristic in a $90^{\circ}$ circular bend by using the PIV(Particle Image Velocimetry) method, this study found the time-mean velocity distribution, time-mean turbulent intensity with turbulent flow for Re = 10,000, 15,000, 20,000, and 25,000 along the test bend. It was found that the highest streamwise velocity of turbulent flow occurs near y/D = 0.5 and the flow moved to y/D =0.15. The peak turbulence intensity shifted toward the concave wall from $\theta= 45 and as \theta$ increased. the intensity decayed along the test tube.

THE $^{13}CO$ DISTRIBUTION AND CORRELATION WITH EXTINCTION IN L134

  • MINN YOUNG KEY;LEE HYE KYUNG
    • Journal of The Korean Astronomical Society
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    • v.29 no.1
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    • pp.75-81
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    • 1996
  • We mapped the $^{13}CO$ line in the dark nebula L134 using the 14-m Taeduck radio telescope with a 57 arcsec beam and one beam spacing. The cloud has a spherical shape with an intensity peak ridge extended from the northwest to the southeast directions. The halfwidth and the radial velocity of the lines peak at the region of the cloud center. The radial velocity decreases from the cloud center towards the north and south directions. The integrated line intensity distributions in the space-velocity plane show some structure and a velocity gradient. The $^{13}CO$ and $H_2CO$ clouds and dark clouds are closely related in space in shape, outer boundary, and intensity peak positions. The $^{13}CO$ integrated line intensity is linearly proportional to the visual extinction.

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A study on the calculation of stress intensity factor for a patched crack using approximate weight function (근사적 가중함수를 이용한 보강된 균열평판의 응력강도계수 계산에 대한 연구)

  • Kim, Jong-Ho;Lee, Soon-Bok
    • Proceedings of the KSME Conference
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    • 2000.11a
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    • pp.123-128
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    • 2000
  • A cracked-plate with a patch bonded on one side is treated with a crack-bridging model: assuming continuous distribution of springs acting between crack surfaces. the approximate weight function was introduced to obtain the stress intensity factor of patched crack subjected to residual stress or non-uniform stress. The stress intensity factors for the partially patched crack within finite plate or the patched crack initiated from a notch were successfully obtained by numerical calculation.

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PIV Measurement on the Flow Characteristics of a Sharp Plane with Inclined Angles (각도변화에 따른 Sharp Plane의 유동특성에 관한 PIV계측)

  • 최종웅;한종석;강호근;문종춘;이영호
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.05a
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    • pp.28-33
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    • 2001
  • Animation understanding and time-resolved analysis of the wake characteristic of 2-D sharp plane flows were executed by applying the multi-vision PIV to a sharp plane(three angle of attacks : $15^{\circ}, \; 30^{\circ}, \; 45^{\circ}$) submerged within a circulating water channel($Re = 2{\times}10^4$). The macroscopic shedding patterns were discussed in terms of instantaneous velocity, vorticity, velocity profile, kinetic energy, turbulent intensity, frequency analysis. Particularly, the time-averaged distribution of turbulent intensity in each experimental cases revealed separate island-like small regions magnitude of turbulent intensity was always strengthened.

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