• Title/Summary/Keyword: synthetic process

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Development of VSI Synthetic Control Chart (가변샘플링기법을 이용한 합성관리도의 개발)

  • Song, Suh-Ill;Park, Hyun-Kyu
    • Journal of Korean Society for Quality Management
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    • v.33 no.1
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    • pp.1-10
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    • 2005
  • This paper develops a new VSI $\={X}-CRL$ synthetic control chart that considers convenience of use in the field, and perception of change of process applying VSI techniques to synthetic control chart, simultaneously. We found the optimal sampling interval and various control limit factor of the suggested chart using markov chain. Comparison and analysis is carried out between synthetic VSI $\={X}-CRL$ chart and other chart in the statistical aspect; $\={X}$ control chart, VSI $\={X}$ chart, another synthetic chart. In case that the process follows normal distribution, the proposed VSI $\={X}-CRL$ synthetic control chart in detecting process mean shift showed the best performance in aspect of statistical performance, regardless of control limit L of CRL/S control chart.

A Synthetic Chart to Monitor The Defect Rate for High-Yield Processes

  • Kusukawa, Etsuko;Ohta, Hiroshi
    • Industrial Engineering and Management Systems
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    • v.4 no.2
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    • pp.158-164
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    • 2005
  • Kusukawa and Ohta presented the $CS_{CQ-r}$ chart to monitor the process defect $rate{\lambda}$ in high-yield processes that is derived from the count of defects. The $CS_{CQ-r}$ chart is more sensitive to $monitor{\lambda}$ than the CQ (Cumulative Quantity) chart proposed by Chan et al.. As a more superior chart in high-yield processes, we propose a Synthetic chart that is the integration of the CQ_-r chart and the $CS_{CQ-r}$chart. The quality characteristic of both charts is the number of units y required to observe r $({\geq}2)$ defects. It is assumed that this quantity is an Erlang random variable from the property that the quality characteristic of the CQ chart follows the exponential distribution. In use of the proposed Synthetic chart, the process is initially judged as either in-control or out-of-control by using the $CS_{CQ-r}$chart. If the process was not judged as in-control by the $CS_{CQ-r}$chart, the process is successively judged by using the $CQ_{-r}$chart to confirm the judgment of the $CS_{CQ-r}$chart. Through comparisons of ARL (Average Run Length), the proposed Synthetic chart is more superior to monitor the process defect rate in high-yield processes to the stand-alone $CS_{CQ-r}$ chart.

Effects of Packing Materials and Inorganic Chemicals During the Start Up in Anaerobic Filter Process (혐기성 생물막법의 Start Up에 있어서의 충진제 및 무기염류의 영향)

  • 정경훈;최형일;신대윤
    • Journal of Environmental Health Sciences
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    • v.20 no.2
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    • pp.73-79
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    • 1994
  • The effects of packing materials in the anaerobic reactor and inorganic chemicals in the synthetic wastewater on the anaerobic treatment during the start up period were investigated using anaeroic filter process. The Ringlace and Honeycomb tube as packing materials were used in the anaerobic reactors. The Ca$^{2+}$ and Fe$^{2+}$ ion concentration as inorganic chemicals contained higher 40 times and 100 times as compared to the control synthetic wastewater, respectively. A start up period 104 and 150 days were necessary to achieve loading rate of 0.37 and 0.74 kg-Toc/m$^3$.d in the anaerobic filter process packed by Ringlace and Honeycomb tube, respectively. The loading rates of the reactor using the synthetic wastewater containing Ca$^{2+}$ (40 times) could be increased faster than in the reactors using the synthetic wastewater containing Fe$^{2+}$ ion (100 times) and control synthetic wastewater. The results of XMA analysis that a lot of the Ca$^{2+}$ ion on the surface of the anaerobic sludge in the anaerobic reactor packed by Ringlace which were fed supplied with synthetic wastewater containing Ca$^{2+}$ ion (40 times) observed as compared to the reactors supplied with control synthetic wastewater and containing Fe$^{2+}$ ion (100 times).

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Analysis of the contents of Practice and Synthetic Application area in Yanbian Textbooks (중국 연변 수학 교과서의 실천과 종합응용 영역에 나타난 학습내용 분석)

  • Lee, Daehyun
    • Journal of the Korean School Mathematics Society
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    • v.16 no.2
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    • pp.319-335
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    • 2013
  • Chinese mathematical curriculum is divided 4 areas(number and algebra, space and figure, statistics and probability, practice and synthetic application). The purpose of this paper is to analyze the contents of the practice and synthetic application in yanbian elementary textbook. For this, 12-textbook which was published in yeonbeon a publishing company is analyze by topic, mathematical process, area of content and mathematical activity. mathematical process The following results have been drawn from this study. First, contextual backgrounds of practice are restricted in classroom. The contents of synthetic application are limited in connection of mathematical areas. Mathematical problem solving is a main in mathematical process, whereas reasoning activity is a few. Mathematical experience activity is a main in mathematical process, whereas synthetic activity is a few. We can use the suggestions of this paper for development of textbook and the contents of mathematical process.

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Improvement of the Synthetic Route for Epinastine Antihistamine (에피나스틴 항히스타민제의 합성법 개선)

  • Baek, Du-Jong;Kim, Moon-Sik
    • Journal of the Korean Chemical Society
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    • v.54 no.4
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    • pp.447-450
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    • 2010
  • In this study, the improved large-scale synthetic route for epinastine hydrochloride, the second-generation antihistamine, was developed. The original synthetic route involves the synthesis of an aminomethyl derivative, the main intermediate, and in this process hazardous materials such as very toxic phosgene and sodium cyanide along with the explosive and expensive aluminum chloride and lithium aluminum hydride were used. In order to improve the synthetic route, we developed industrially very useful process to prepare the aminomethyl intermediate by the synthesis of the phthalimidomethyl derivative first and easy removal of the phthalyl group using hydrochloric acid or methyl hydrazine, and hazardous materials and expensive reagents were excluded in this process.

Current Status of Quartz Glass for Semiconductor Process (반도체 공정용 석영유리 현황)

  • Kim, Hyeong-Jun
    • Ceramist
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    • v.22 no.4
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    • pp.429-451
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    • 2019
  • Quartz glass is a key material for making semiconductor process components because of its purity, low thermal expansion, high UV transmittance and relatively low cost. Domestic quartz glass has a market worth about 500 billion won in 2018, and the market power of Japanese materials is very high. Quartz glass for semiconductor process can be divided into general process and exposure. For general process, molten quartz glass is mainly used, but synthetic quartz glass with higher purity is preferred. Synthetic quartz glass is used as the photomask for the exposure process. Recently, as semiconductors started the sub-nm process, the transition from the transmission type using ArF ultraviolet (194 nm) to the reflection type using EUV ultraviolet (13.5 nm) began. Therefore, the characteristics required for the synthetic quartz glass substrates used so far are also rapidly changing. This article summarizes the current technical trends of quartz glass and recent technical issues. Lastly, the present situation and development possibility of quartz glass technology in Korea were diagnosed.

Degradation of synthetic dye in water by solution plasma process

  • Panomsuwan, Gasidit;Morishita, Tetsunori;Kang, Jun;Rujiravanit, Ratana;Ueno, Tomonaga;Saito, Nagahiro
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.10
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    • pp.888-893
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    • 2016
  • In this study, the solution plasma process was utilized with the aim of degrading synthetic dyes in water at atmospheric pressure. The experiments were conducted in a batch-type reactor consisting of a symmetric wire-wire electrode configuration with rhodamine B (RhB) as the target synthetic dye. The effects of the plasma treatment time and initial dye concentration on the RhB degradation were investigated by monitoring the change in absorbance of RhB solutions. The RhB solutions turned lighter in color and finally colorless with prolonged plasma treatment time, indicating the destruction of dye molecules. The RhB solutions were found to have degraded, following the first-order kinetic process. However, for high initial RhB concentrations, another kinetic process or factor seems to play a dominant role at the initial degradation stage. The fitted first-order rate constant decreased as the initial concentration increased. This result suggests that the degradation behavior and kinetic process of the RhB solution strongly depends on its initial concentration. The RhB degradation is considered to be due to a combination of factors, including the formation of chemically oxidative species, as well as the emission of intense UV radiation and high-energy electrons from the plasma. We believe that the solution plasma process may prove to be an effective and environment-friendly method for the degradation or remediation of synthetic dye in wastewater.

Temperature Effect in the process of DAF as pretreatment of SWRO (해수담수화 전처리로서 DAF공정에서 고온의 해수에 대한 영향 특성)

  • Park, Hyunjin;Dockko, Seok
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.807-813
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    • 2012
  • Flocculation and flotation are used as pretreatment steps prior to the reverse osmosis (RO) process. During seawater treatment, high temperature can change the water chemistry of seawater during the process of coagulation. It also affects bubble volume concentration (BVC) and bubble characteristics. Coagulants such as alum and ferric salts at $40^{\circ}C$ can also change flux rates in the seawater reverse osmosis (SWRO) process. In this study, the bubble characteristics in dissolved air flotation (DAF), used as a SWRO pretreatment process, were studied in synthetic seawater at $20^{\circ}C$ and $40^{\circ}C$. The flux of an RO membrane was monitored after dosing the synthetic seawater with coagulants at different temperatures. Results showed that BVC increases as the operating pressure increases and as the salt concentration decreases. The bubble size released at $40^{\circ}C$ is far smaller than that at $20^{\circ}C$The addition of a ferric salt is effective for turbidity removal in synthetic seawater at $20^{\circ}C$; it is more effective than alum. When synthetic seawater was dosed with a ferric salt, the RO membrane flux increased by 27 % at $40^{\circ}C$.

Development of a Process Technique for Heavy Metal Removal in the Production of Recycled Synthetic Resin Materials (재생 합성수지 원료생산을 위한 중금속 이물질 제거 공정기술 개발)

  • Kim, Jung-Ho;Cha, Cheon-Seok;Kim, Jae-Yeol;Kim, Ji-Hoon
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.17 no.4
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    • pp.137-142
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    • 2018
  • Recycled synthetic resin materials produced from waste vinyl and waste plastic contain many foreign substances. Plastic products made from this recycled resin materials containing foreign substances are of poor quality, with reduced the strength and rigidity. Foreign substances include heavy metals, cement, foil, dyed paper and dust. In this study, the scratch-Dies process; which remove foreign sbustances, with precision and automation, through a three-stage mesh filter, is designed. The process is evaluated with finite element analysis according to vibration loading and make. After installing the manufactured equipment, recycled resin was producde, and its heavy metal content was evaluated. Recycled synthetic resin materials were also used plastic products and evaluate their strength. In addition, the change in production was assessed.

A Study on the Adjustment Synthetic Control Chart Pattern for Detecting Shifts using Individual Observations in Start-Up Process (초기공정에서 공정변화에 대한 개별 관측치를 이용한 수정된 합성 관리도 연구)

  • 지선수
    • Journal of Korea Society of Industrial Information Systems
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    • v.7 no.4
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    • pp.53-58
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    • 2002
  • This paper presents a adjustment synthetic control chart that is an integration of the Shewhart X chart and the conforming run length(CRL) chart. The application of the adjustment synthetic control chart my therefore substantially enhance the effectiveness process control for manufacturing. In the synthetic control chart, denotes the average number of the X sample required to detect a process shift. The synthetic control chart outperforms the EWM chart and the X chart when σ is greater than 0.75σ. And the X-CRL charts suggested above evaluate using the conditional probability.

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