• Title/Summary/Keyword: chemical communication

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A Comparative Study on the Compliance Program(CP) of Strategic Export Control System between Korea and Japan (전략물자 수출통제 자율준수제도(CP)에 관한 한.일 비교 연구)

  • Shim, Sang-Ryul;Shao, Dan;Joo, E-Wha
    • International Commerce and Information Review
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    • v.13 no.4
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    • pp.297-321
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    • 2011
  • Under the UN Security Council Resolution 1540/1810 in 2004 to restrict the proliferation of WMD (weapons of mass destruction) and their means of delivery, many countries have taken great efforts to, control the export of strategic items, thereby preventing the transfer of ABCM (atomic, biological, chemical weapons, missiles) and technologies and goods related to conventional weapons or dual-use items, Compliance Program (CP) in Korea or Internal Compliance Program(ICP) in Japan refers to a company's internal system or rules to comply with the export control laws and regulations, and is to prevent the unintentional illegal export of strategic items. This paper analyzes the Compliance Program (CP) of strategic export control system between Korea and Japan. Both countries have very similar legal frameworks under the guiding principles of multilateral export control regimes. However, there are some differences in actual procedures, classification service, supporting system, export license, sanctions for illegal exporters, etc. Korea should take more active and customer-oriented measures to promote the Compliance Program (CP) into Korean export companies for better awareness and positive attitude, practical information and education, smoothy government-firm communication, closer cooperation between Korea and Japan, etc.

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Design of 1.0V O2 and H2O2 based Potentiostat (전원전압 1.0V 산소 및 과산화수소 기반의 정전압분극장치 설계)

  • Kim, Jea-Duck;XIAOLEI, ZHONG;Choi, Seong-Yeol;Kim, Yeong-Seuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.2
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    • pp.345-352
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    • 2017
  • In this paper, a unified potentiostat which can measure the current of both $O_2$-based and $H_2O_2$-based blood glucose sensors with low supply voltage of 1.0V has been designed and verified by simulations and measurements. Potentiostat is composed of low-voltage operational transconductance amplifier, cascode current mirrors and mode-selection circuits. It can measure currents of blood glucose chemical reactions occurred by $O_2$ or $H_2O_2$. The body of PMOS input differentional stage of the operational transconductance amplifier is forward-biased to reduce the threshold voltage for low supply voltage operation. Also, cascode current mirror is used to reduce current measurement error generated by channel length modulation effects. The proposed low-voltage potentiostat is designed and simulated using Cadence SPECTRE and fabricated in Magnachip 0.18um CMOS technology with chip size of $110{\mu}m{\times}60{\mu}m$. The measurement results show that consumption current is maximum $46{\mu}A$ at supply voltage of 1.0V. Using the persian potassium($K_3Fe(CN)_6$) equivalent to glucose, the operation of the fabricated potentiostat was confirmed.

Process Optimization of the Contact Formation for High Efficiency Solar Cells Using Neural Networks and Genetic Algorithms (신경망과 유전알고리즘을 이용한 고효율 태양전지 접촉형성 공정 최적화)

  • Jung, Se-Won;Lee, Sung-Joon;Hong, Sang-Jeen;Han, Seung-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.11
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    • pp.2075-2082
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    • 2006
  • This paper presents modeling and optimization techniques for hish efficiency solar cell process on single-crystalline float zone (FZ) wafers. Among a sequence of multiple steps of fabrication, the followings are the most sensitive steps for the contact formation: 1) Emitter formation by diffusion; 2) Anti-reflection-coating (ARC) with silicon nitride using plasma-enhanced chemical vapor deposition (PECVD); 3) Screen-printing for front and back metalization; and 4) Contact formation by firing. In order to increase the performance of solar cells in terms of efficiency, the contact formation process is modeled and optimized using neural networks and genetic algorithms, respectively. This paper utilizes the design of experiments (DOE) in contact formation to reduce process time and fabrication costs. The experiments were designed by using central composite design which consists of 24 factorial design augmented by 8 axial points with three center points. After contact formation process, the efficiency of the fabricated solar cell is modeled using neural networks. Established efficiency model is then used for the analysis of the process characteristics and process optimization for more efficient solar cell fabrication.

The characteristics of silicon nitride thin films prepared by atomic layer deposition with batch type reactor (Batch-Type 원자층 증착 방법으로 형성한 실리콘 질화막의 특성)

  • Kim, Hyuk;Lee, Ju-Hyun;Han, Chang-Hee;Kim, Woon-Joong;Lee, Yeon-Seung;Lee, Won-Jun;Na, Sa-Kyun
    • Journal of the Korean Vacuum Society
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    • v.12 no.4
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    • pp.263-268
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    • 2003
  • Precise thickness control and excellent properties of silicon nitride thin films are essential for the next-generation semiconductor and display devices. In this study, silicon nitride thin films were deposited by batch-type atomic layer deposition (ALD) method using $SiC1_4$ and $NH_3$ as the precursors at temperatures ranging from 500 to $600^{\circ}C$. Thin film deposition using a batch-type ALD reactor was a layer-by-layer atomic growth by self-limiting surface reactions, and the thickness of the deposited film can be controlled by the number of deposition cycles. The silicon nitride thin films deposited by ALD method exhibited composition, refractive index and wet etch rate similar with those of the thin films deposited by low-pressure chemical vapor deposition method at $760^{\circ}C$. The addition of pyridine mixed with precursors increased deposition rate by 50%, however, the films deposited with pyridine was readily oxidized owing to its unstable structure, which is unsuitable for the application to semiconductor or display devices.

Fabrication of Inductors, Capacitors and LC Hybrid Devices using Oxides Thin Films (산화물 박막을 이용한 인덕터, 캐패시터 및 LC 복합 소자 제조)

  • Kim, Min-Hong;Yeo, Hwan-Guk;Hwang, Gi-Hyeon;Lee, Dae-Hyeong;Kim, In-Tae;Yun, Ui-Jun;Kim, Hyeong-Jun;Park, Sun-Ja
    • Korean Journal of Materials Research
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    • v.7 no.3
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    • pp.175-179
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    • 1997
  • bliniaturization oi microwave circuit components is an important issue with the development in the mobile communication. Capacitors, inductors anti hybrid devices of these are building blocks of electric circuits, and the fabrication of these devices using thin film technology will influence on the miniaturization of electronic devices In this paper, we report the successful fabrication of the inductors, capacitors and LC hybrid devices using a ferroelectric and a ferromagnetic oxide thin iilm. Au, stable at high temperatures in oxidizing ambient, is patterned by lift-off process, and oxide thin films are deposited by ion beam sputtering and chemical vapor deposition. These devices are characterized by a network analyzer in 0.5-15GtIz range We got the inductance of 5nH, capacitance oi 10, 000 pF and resonant frequencies of $10^{6}-10^{9}Hz$.

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The Improvement of Fabrication Process for a-Si:H TFT's Yield (a-Si:H TFT의 수율 향상을 위한 공정 개선)

  • Hur, Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.6
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    • pp.1099-1103
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    • 2007
  • TFT's have been intensively researched for possible electronic and display applications. Through tremendous engineering and scientific efforts, a-Si:H TFT fabrication process was greatly improved. In this paper, the reason on defects occurring at a-Si:H TFT fabrication process is analyzed and solved, so a-Si:H TFT's yield is increased and reliability is improved. The a-Si:H TFT of this paper is inverted staggered type TFT. The gate electrode is formed by patterning with length of $8{\mu}m{\sim}16{\mu}m$ and width of $80{\sim}200{\mu}m$ after depositing with gate electrode (Cr). We have fabricated a-SiN:H, conductor, etch-stopper and photo-resistor on gate electrode in sequence, respectively. We have deposited n+a-Si:H, NPR(Negative Photo Resister) layer after forming pattern of Cr gate electrode by etch-slower pattern. The NPR layer by inverting pattern of upper Sate electrode is patterned and the n+a-Si:H layer is etched by the NPR pattern. The NPR layer is removed. After Cr layer is deposited and patterned, the source-drain electrode is formed. The a-Si:H TFT made like this has problems at photo-lithography process caused by remains of PR. When sample is cleaned, this remains of PR makes thin chemical film on surface and damages device. Therefor, in order to improve this problem we added ashing process and cleaning process was enforced strictly. We can estimate that this method stabilizes fabrication process and makes to increase a-Si:H TFT's yield.

The Learning Stress, Immersion and Satisfaction in FTF and NFTF Classes of Major Subjects in Junior College

  • Gyeoung-Ran, Moon
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.3
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    • pp.91-100
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    • 2023
  • This study is a case study comparing and examining the effects of non-face-to-face(NFTF) classes in the 2021-2 semester and face-to-face(FTF) classes in the 2022-2 semester on learning immersion, learning stress, and learning satisfaction. The learning immersion and learning satisfaction of 240 students were analyzed in NFTF and FTF classes of department S of C junior college where the same textbook, same subject, and same professor were taught. For data processing, SPSS Ver. 23.0 was used. The data is used to measure reliability by Cronbach's α, t-test, Pearson's correlation coefficient, and multiple regression analysis. The results of this study are as follows. First, learners' learning immersion was higher in FTF than NFTF classes among engineering major subjects. Second, it was found that there was a difference in learning stress according to the types of FTF and NFTF classes in engineering major subjects. Third, it was found that there were differences in practice content, communication, and task performance of sub-factors of learning satisfaction according to FTF and NFTF class types in engineering major subjects. In conclusion, it was found that FTF classes had a more positive effect on learning immersion and satisfaction, and NFTF classes had a more negative effect on learning stress.

Impact of Oil Price Shocks on Stock Prices by Industry (국제유가 충격이 산업별 주가에 미치는 영향)

  • Lee, Yun-Jung;Yoon, Seong-Min
    • Environmental and Resource Economics Review
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    • v.31 no.2
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    • pp.233-260
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    • 2022
  • In this paper, we analyzed how oil price fluctuations affect stock price by industry using the non-parametric quantile causality test method. We used weekly data of WTI spot price, KOSPI index, and 22 industrial stock indices from January 1998 to April 2021. The empirical results show that the effect of changes in oil prices on the KOSPI index was not significant, which can be attributed to mixed responses of diverse stock prices in several industries included in the KOSPI index. Looking at the stock price response to oil price by industry, the 9 of 18 industries, including Cloth, Paper, and Medicine show a causality with oil prices, while 9 industries, including Food, Chemical, and Non-metal do not show a causal relationship. Four industries including Medicine and Communication (0.45~0.85), Cloth (0.15~0.45), and Construction (0.5~0.6) show causality with oil prices more than three quantiles consecutively. However, the quantiles in which causality appeared were different for each industry. From the result, we find that the effects of oil price on the stock prices differ significantly by industry, and even in one industry, and the response to oil price changes is different depending on the market situation. This suggests that the government's macroeconomic policies, such as industrial and employment policies, should be performed in consideration of the differences in the effects of oil price fluctuations by industry and market conditions. It also shows that investors have to rebalance their portfolio by industry when oil prices fluctuate.

A Case Study for Developing 'Personal Practical Knowledge(PPK)' of Pre-service Chemistry Teachers: Based on the Reflective Discussion of Community of Practice(CoP) Activity (예비 화학교사들의 실천적 지식(PPK) 함양을 위한 사례연구 -실행공동체(CoP) 활동의 반성적 논의를 중심으로-)

  • Kim, Yu-Jung;Hong, Hun-Gi
    • Journal of The Korean Association For Science Education
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    • v.37 no.2
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    • pp.347-358
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    • 2017
  • The purpose of this study is to research on the professional development of pre-service chemistry teachers in terms of personal practical knowledge(PPK), and draw a discussion for pre-chemistry teacher education. A reflective discussion through a Community of Practice(CoP) activity has been conducted with 5 pre-service chemistry teachers studying in a college of education located in Seoul. The analysis of the results reveals that 'Subject-matter knowledge' is leaning toward massive chemical contents, 'Curriculum knowledge' is below the level of selecting, analyzing, and applying curriculum materials. 'Instruction knowledge', especially the knowledge of chemistry experiment and research, is not enough to lead secondary students' scientific experiment. 'Milieu of school knowledge' is stunted in growth for the reason of communication-deficiency between a college of education and a community, and among education- related groups. 'Self-knowledge' has been diminished not only because there is a bad influence from college classmates not wanting to be a teacher, but also a lack of communication in the chemistry-education department which can make pre-teachers' belief strong. In conclusion, it is especially needed for the chemistry-education department to strengthen pre-teachers' 'Self-knowledge' in order to develop PPK. This study suggests operating 'a professional community' that has a periodic meeting with pre-service teachers, teachers, professors, community people, education practitioners, and researchers. In addition, it would be effective for increasing pre-teachers' PPK to reconsider depth and direction of 'Subject-matter knowledge', to give an opportunity to examine curriculum materials critically and reorganize them, to improve the course of chemistry experimental subject to the way of improving pre-teachers' leadership in chemistry inquiry experiment, and to raise the quality of educational service activities.

Application of Oral Acute Toxic Class Method and Globally Harmonized Classification System on Pesticide (국내에서 농약에 대한 급성경구독성등급법 적용 및 GHS 체계 도입 제안)

  • Jeong, Mi-Hye;You, Are-Sun;Park, Kyung-Hun;Kim, Byung-Seok;Lee, Hee-Dong;Lee, Jae-Bong;Kwon, Oh-Kyung
    • The Korean Journal of Pesticide Science
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    • v.12 no.2
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    • pp.141-147
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    • 2008
  • Globally Harmonized System (GHS) for classification and labelling will provide an internationally agreed hazard classification system of chemical products and for communication of those hazards. This study aimed for establishment of the oral acute toxic class (ATC) method and application of GHS on pesticides. The ATC method was developed for determining $LD_{50}$ estimates of chemical substances with significantly fewer animals than needed when applying conventional $LD_{50}$ tests. We carried out $LD_{50}$ test and ATC test on 13 pesticides, Although methidathion EC and parathion-ethyl EC showed significantly different in $LD_{50}$ values between $LD_{50}$ test and ATC method, there are no difference in toxicity class by GHS. Both tests on the other pesticides showed almost equal results and toxicity class by GHS. Therefore, this study indicated high possibility of application of ATC method and GHS on pesticides.