• Title/Summary/Keyword: fixed form

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Surface energy change and hydrophilic formation of PE, PS and PTFE films modification by hydrogen ion assisted reaction

  • Jung Cho;Ki Hyun;Koh, Seok-Keun
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.202-202
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    • 1999
  • The Polyethylene (PE), Polystyrene (PS) and Polytetrafluoroethylene (PTFE) surface modification was investigated by hydrogen io assisted reaction (H-IAR) in oxygen environment. The IAR is a kind of surface modification techniques using ion beam irradiation in reactive gas environment. The energy of hydrogen ion beam was fixed at 1keV, io dose was varied from 5$\times$1014 to 1$\times$1017 ions/$\textrm{cm}^2$, and amount of oxygen blowing gas was fixed 4ml/min. Wettability was measured by water contact angles measurement, and the surface functionality was analyzed by x-ray photoelectron spectroscopy. The contact angle of water on PE modified by argon ion beam only decrease from 95$^{\circ}$ to 52$^{\circ}$, and surface energy was not changed significantly. But, the contact angle using hydrogen ion beam with flowing 4ml/min oxygen stiffly decreased to 8$^{\circ}$ and surface energy to 65 ergs/cm. In case of PS, the contact angle and surface energy changes were similar results of PE, but the contact angle of PTEE samples decreased with ion dose up to 1$\times$1015 ions/$\textrm{cm}^2$, increased at higher dose, and finally increased to the extent that no wetting was appeared at 1$\times$1017 ions/$\textrm{cm}^2$. These results must be due to the hydrogen ion beam that cleans the surface removing the impurities on polymer surfaces, then hydrogen ion beam was activated with C-H bonding to make some functional groups in order to react with the oxygen gases. Finally, unstable polymer surface can be changed from hydrophobic to hydrophilic formation such as C-O and C=O that were confirmed by the XPS analysis, conclusionally, the ion assisted reaction is very effective tools to attach reactive ion species to form functional groups on C-C bond chains of PE, PS and PTFE.

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A Study on Investment Agreement and Dispute Resolution System of FTA (FTA 투자협정과 분쟁해결제도에 관한 연구)

  • Choe, Tae-Parn
    • Journal of Arbitration Studies
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    • v.17 no.2
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    • pp.141-165
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    • 2007
  • This study aims to make a contribution to the promotion of trade and economic development of South Korea, and, at the same time, call attention to the increasing trend of investment agreements concluded within Free Trade Agreements (FTA) by examining theoretically FTAs and dispute resolution and investigating systematically the conclusion procedure of agreements, and the system, institutions, and jurisdiction of dispute resolution, and presenting these findings to the government and investors involved. The most problematic aspect in the legal process of arbitration involving disputes over investment is that of arguments concerning the right of jurisdiction. When a dispute arises, even though an investor files for arbitration at an ICSID institution, the parties become involved in another energy-consuming argument even before proceeding to the hearing and decision of the original plan in cases in which the respondent of the dispute files an objection to the decision rights of the arbitral tribunal. As the main basis for this type of plea, the point of non-existence of jurisdiction is first raised where the applicable dispute does not fall under the range of investments defined in individual investment contracts or investment agreements such as a Bilateral Investment Treaty (BIT). To avoid an open-ended definition of investment for the range of investments, articles concerning investments in the FTA and NAFTA between Canada and the USA adopt the limited closed-list method. Article 96 of the FTA between Japan and Mexico applied the same abovementioned method of limited form of definition regarding range of investments and concluded BITs between member countries of APEC applied a similar method as well. Instead of employing the previously used inclusive definition, the BITs concluded between countries of Latin America and the USA are equipped with limited characteristics of an investment. Furthermore, to correspond with this necessary condition the three following requirements are needed : 1) fixed investment funding; 2) expected profits resulting from such investments; 3) and the existence of fixed risk bearing.

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A Study on Standardization of Pattern Design of Korean Men's Traditional Trousers (한복바지 원형설계의 표준화를 위한 연구)

  • 정옥임
    • Journal of the Korean Home Economics Association
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    • v.39 no.10
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    • pp.97-109
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    • 2001
  • It is thought that a composition of trousers is related to fabrics with single breadth. Therefore, trousers are designed with pattern using this fabrics with single breadth. However, in the old pattern of trousers, the breadth of 33cm-35cm was not considered in designing patterns. In this context, deciding which pattern design is better is not easy as there are a variety of estimation methods. So in this study, standardization of drafting is pursued by an objective pattern design. For this, a base angle of the trouser closely relating to a form and function was measured and using the height and the base angle, a trouser pattern design was tried. For a measurement of the base angle, 5 subject were selected. They are 25-29 year-old male graduates with fine physical standard. The base angle was measured with symphysis pubis point as a standard when subjects sat with their legs crossed, when they stood with their legs open (not forced artificially) and when they laid down with their legs open. The distance between a knee inside joint and knees was measured three times and the resultant value was used for the pattern design. For a design of trousers, the height was applied and the base angle was fixed. As a pattern drawing, using the height, a base angle and circumference of the hip, a trouser was designed. The production method for the pattern design is as follow: (1) The length formula, is height + $\frac{height}{2}$ (2) The hip girth formula is $\frac{hipgirth}{2}$ - $\frac{hipgirth}{20}$(3) A crotch angle is fixed at $72^{\circ}$. (4) The ratio of outer leg length to leg width is 5 : 8. (5) The component ratio of the upper outer leg length to the pant length is 5 : 8. (6) The ratio of the division point of front right inner leg length and left inner width to upper outer leg length is 5 : 8.

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Optimization of Drive-in Process with Various Times and Temperatures in Crystalline Silicon Solar Cell Fabrication (결정질 실리콘 태양전지 도핑 확산 공정에서 시간과 온도 변화에 의한 Drive-in 공정 연구)

  • Lee, Hee-Jun;Choi, Sung-Jin;Myoung, Jae-Min;Song, Hee-Eun;Yu, Gwon-Jong
    • 한국태양에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.51-55
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    • 2011
  • In this paper, the optimized doping condition of crystalline silicon solar cells with 156 ${\times}$ 156 mm2 area was studied. To optimize the drive-in condition in the doping process, the other conditions except drive-in temperature and time were fixed. After etching 7 ${\mu}m$ of the surface to form the pyramidal structure, the silicon nitride deposited by the PECVD had 75~80 nm thickness and 2 to 2.1 for a refractive index. The silver and aluminium electrodes for front and back sheet, respectively, were formed by screen-printing method, followed by firing in $400-425-450-550-850^{\circ}C$ five-zone temperature conditions to make the ohmic contact. Drive-in temperature was changed in range of $828^{\circ}C$ to $860^{\circ}C$ and time was from 3 min to 40 min. The sheet resistance of wafer was fixed to avoid its effect on solar cell. The solar cell fabricated with various conditions showed the similar conversion efficiency of 17.4%. This experimental result showed the drive-in temperatures and times little influence on solar cell characteristics.

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Application of Synergistic Solvent Extraction by Formation of Ternary Complex for Determination of Trace Zn(II) in Water Samples

  • Choi, Jong-Moon;Park, Hyun-Mo;Choi, Sun-Do
    • Bulletin of the Korean Chemical Society
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    • v.27 no.4
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    • pp.563-567
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    • 2006
  • The application of a synergistic solvent extraction by the formation of ternary complex with pyrocatechol violet (PV) and benzalkonium chloride (BC) was studied for determination of trace Zn(II) in water samples. The pH of sample solution and the amount of PV and BC added were optimized for the formation of the stable complex, a proper solvent was selected for the effective extraction, and the concentration of nitric acid was fixed for the back extraction of the complex from the solvent. After the ionic strength of 100 mL sample solution was adjusted to 0.1 M by adding NaCl and the pH was fixed at 9 with a carbonate buffer, 1.0 mL of 2% PV solution was added to form Zn(II)-PV complex then the Zn(II)-PV/BC ternary complex was made by adding 1.0 mL of 10% BC solution. The ternary complex was extracted into 10 mL of MIBK. And the ternary complex was back-extracted with 10 mL of 1.0 mol/L nitric acid to determine Zn(II) by a flame atomic absorption spectrophotometer (flame-AAS). The interference of concomitant ions on the extraction of Zn(II) was investigated. This procedure was applied to the analysis of three real samples such as Dalbang-dam water, laboratory tap water and Jungnajin seawater. The recoveries of Zn(II) in spiked samples were 86.58-104.1%.

Three-dimensional evaluation of the internal adaptation of single and three-unit fixed dental restoration by CAD/CAM milling system (CAD/CAM 밀링 시스템을 활용한 단일 치관과 3본 교의치의 3D 적합도 평가)

  • Kim, So-Ri;Kim, Chong-Myeong;Kim, Woong-Chul;Kim, Ji-Hwan
    • Journal of Technologic Dentistry
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    • v.39 no.1
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    • pp.35-42
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    • 2017
  • Purpose: The purpose of this paper was to evaluate the occurrence of errors regarding adaptation by conducting a three-dimensional assessment comparing the bridge type dental restoration after the cutting process, which has multiple abutments, with a single type dental restoration. Methods: By using ten identical files obtained by scanning the master model, thirty designs were created consisting of ten maxillary right first premolars and ten maxillary right first molars with single crown abutments, along with ten bridge designs with the identical abutment. A 5-axis milling machine was used to produce the design file. The produced denture prostheses were scanned using a silicone replica for a STL file. An evaluation was conducted using 3D analysis software on the master model and each of the thirty data files. Results: The RMS value of the pre-molar (14) was $38.4{\pm}4{\mu}m$ for single and $54.7{\pm}6{\mu}m$ for bridge abutment; therefore, a statistically significant difference was observed for single and bridge designs although both shared the same abutment form (P<.05). Also, the RMS value of the molar (16) was $47.6{\pm}2{\mu}m$ and $56.6{\pm}5{\mu}m$ for the single and bridge designs, respectively, thereby presenting a statistically significant difference (P<.05). Conclusion: As a result, dental prosthesis fabricated using the single method presented better internal adaptation outcomes.

Comparative Analysis on Interior Spaces of the Selected Historical Residences in the Western and Eastern Countries - focusing on case residences of Korea, China, Japan, Rome, Egypt, and Italy - (동서양 전통적인 주택 양식의 실내공간 특성 비교분석 연구 - 한국, 중국, 일본, 로마, 이집트, 이태리의 사례주택을 중심으로-)

  • 김연정;이연숙
    • Korean Institute of Interior Design Journal
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    • no.27
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    • pp.152-161
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    • 2001
  • At the multi-cultural society, research is needed to encourage a social atmosphere for enhanced understanding and respect for different cultures & countries. The purpose was to analyze the characteristics of spatial arrangement, space connection, Interior decoration and the relationship among these three features, which showed each country's unique housing form tradition. Three representative cases of historic residences from each country were selected on the basis of a recognized historic architecture directory. Total 18 residences from 6 countries - Korea, China, Japan, Rome, Egypt, and Italy - were comparatively analyzed. As results, aspects generally found in Eastern countries, were the fence as the semi-open boundary between the inside and the outside of the house, the flexibility of spatial opening and partitions between rooms, and finally simple and movable decoration features. On the other hands, aspects appeared in Western countries, were the outer wall of the building as the boundary to the outside, the closed and fixed properties of the room partitions, and finally complex and fixed decoration features. The research also showed that even within the same culture, the degree of openness varied. Each feature of space was related and could be explained within the same context. Housing, regardless of country and culture, tried to accommodate the exterior space inside the building as much as possible. The common pursuit was transformed to various visible forms and its reason might be due to different socio-cultural and environmental backgrounds that need to be continuously explored in academic area.

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Theoretical Investigation of 2DOF Vibrating System and Its Application to Dynamic Vibration Absorber (2자유도 진동계에 관한 이론적 고찰 및 진동흡진기로의 응용)

  • Jang, Seon-Jun;Brennan, M.J.;Rustigh, E.;Jung, Hyung-Jo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.4
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    • pp.371-377
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    • 2009
  • In this paper, the dynamic characteristic of vibrating system which has translational and rotational degrees of freedom is studied. The moment of inertia of the system is modeled here as the inerter and the equivalent model to the system is proposed using dynamic stiffness method. It is shown that the size of inerter plays a major role to determine the dynamic characteristic of the system. This two degree of freedom system(DOF) is applied as a dynamic vibration absorber(DVA) to the elimination of single peak of main body. The solution for the undamped DVA is presented in analytical form while the damped DVA is designed using fixed point theory. The numerical examples are presented for verifying the methods.

Comparison of Clinical Development and Evaluation of Triple Antihypertensive Therapy in Advanced Foreign Countries (항고혈압 약물 3종 복합제에 대한 선진 외국의 임상자료 심사사례 비교)

  • Wang, So Young;Shon, Soo Jung;Um, Jung Yoon;Lim, Hwa Kyung;Lim, Sook;Kang, Seung Ho;Lee, Sun Hee
    • Korean Journal of Clinical Pharmacy
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    • v.23 no.3
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    • pp.239-247
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    • 2013
  • Background: Fixed drug combinations are formulations containing two or more active ingredients in a single dosage form. Such combination therapies are commonly applied to improve efficacy, reduce adverse events and replace co-administration, etc. National and international guidelines for hypertension treatment recommend addition of other classes of antihypertensive drugs rather than incremental dose of mono-therapy, when blood pressure is not adequately controlled. Thus, many dual combinations of antihypertensive drugs have been approved and pharmaceutical companies are recently interested in developing antihypertensive triple combinations. Clinical trial designs for the fixed combinations are various depending on the target patients, dosage and clinical endpoints. Thereby, further discussions for the clinical trials of antihypertensive triple therapies are required regarding the indication claimed. Conclusion: This article provides a review for the assessment of the label and medical reports of the clinical trials on antihypertensive triple therapies in advanced foreign countries.

Development of Baking Technology and Analysis of Domestic and International Bakery Market and Trends (제과제빵 기술의 발전과 베이커리 시장의 분석)

  • Lee, Kwang-Suck
    • Food Science and Industry
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    • v.45 no.4
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    • pp.16-20
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    • 2012
  • Although the technology of breadmaking simply goes through the process of mixing, fermentation, and baking, it is very hard to make a same product every day. The reason is that baking science begins with the very first process of breadmaking which is mixing, and every steps and working environments are so closely connected. The baking science has developed in short time since the theory of fermentation has released. If you check the development of baking technology synthetically, it is consisted of the discovery of nutritional and functional ingredients, the optimization process of new machines, and the maintenance of the quality as fulfilling social demands. Because the baking business is making and selling the product, baking itself is a business, and it has the form that manufacturing and service business coexist. In today's current domestic bakery market, the supply exceeds the demand. Moreover, the concept of bakery itself has been changing from the fixed image of bakery which is selling the bread to the differentiated bakery with others. As we look at the general bakery's trends, it is focused on going back to the basic or traditions, going to the functional, and working with automations. To conclude, the baking has a long history, but it actually has the short history in the technological development. Baking business can be viewed as the simple business, but many factors are related to the business. It has a few basic kinds of products in baking, but it has diverse kinds of products with the base of infinite creativity. Even though it is physically a hard working business, it is also a business that can face with fun. For managing a bakery, finally, the differentiated strategy with other bakery that maximizes the customers' value is needed.