• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회A
• /
• pp.461-466
• /
• 2007

There has been a great interest in printing technology as a low cost and mass production method for the application of printed electronics such as printed TFT, solar cell, RFID Tag, printed battery, and so on. In this study, apparatuses of gravure-offset printing are developed for fine line-width/gap printing and examining pattern distortion occurred in gravure-offset printing process. The fine line-width/gap pattern shows that it is possible to make around 20 micro-meter line-width/gap printing patterns. Pattern distortion is modeled, and the amount and shape of the distortion are calculated by using commercial FEM code. The roll-to-roll printing system under development consists of unwinder/rewinder, two printing units, one coating unit, drying units, guiding unit, vision system, and other auxiliary devices. For multi-layer printing, the system is designed to be capable of printing two different materials.

• 한국세라믹학회지
• /
• 제56권4호
• /
• pp.354-359
• /
• 2019

Information security films that can ensure personal privacy by reducing the viewing angle of display screens were fabricated by microlouver patterning and a ZnO nano-ink filling process. Optical simulation results demonstrated that all the microlouver films showed good security performances. Security performances were evaluated as calculated relative luminance ratios compared between the side and front. Based on the simulation results, microlouver films were fabricated by UV imprint lithography and nano-ink bar coating. However, distortion of the microlouver pattern occurred with the use of high-viscosity nano-inks such as ZrO₂ and TiO₂, and the CuO-filled microlouver film suffered from very low optical transmittance. Accordingly, the effects of ZnO filling height on security performance were intensively investigated through simulation and experimental measurements. The fabricated microlouver film with a 75-㎛-high ZnO filling exhibited a good relative luminance ratio of 0.75 at a 60° side angle and a transmittance of 44% at a wavelength of 550 nm.

• 반도체디스플레이기술학회지
• /
• 제19권1호
• /
• pp.79-84
• /
• 2020

Unlike a printing process, it is difficult to pattern organic thin films in the longitudinal (coating) direction using a coating process. In this paper, we have investigated the feasibility of patterning organic thin films using needles. To this end, we have slot-coated an aqueous poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) solution in the form of a fine stripe or large area and then applied the dual needle; one for discharging the main solvent of the underlying thin film and the other for sucking the dissolved thin film. We have found that the pattern width and depth increase as the moving speed of the plate decreases. However, it is observed that the sidewall slope is very gentle (the length of the slope is of the order of 200 ㎛) due to the fact that the discharged main solvent is widely spread and then isotropic etching occurs. With this scheme, we have also demonstrated that a fine stripe can be obtained by scanning the dual needle closely. To demonstrate its applicability to solution-processable organic light-emitting diodes (OLEDs), we have also fabricated OLED with the patterned PEDOT:PSS stripe and observed the insulation property in the strong light-emitting stripe.

• 대한한의학원전학회지
• /
• 제26권2호
• /
• pp.47-59
• /
• 2013

Objective : Syndrome differentiation(辨證) has clinical importance in East Asian Traditional Medicine. There are several ways for Syndrome differentiation. However, Eight Principle Pattern Identification(八綱辨證) is the base of other Syndrome differentiations. Of the physicians focused on Eight Principle Patterns(八綱), I have researched for Eight Principle Pattern Identification concerning with Zhang Jie-Bin(張介賓), Cheng Guo-Peng(程國彭), and Jiang Han-Tun(江涵暾) in Ming(明) and Qing(淸.) Method : Applying to Eight Principle Pattern Identification, I have researched comparatively for 3 kinds for. First, Zhang Jie-Bin's Jingyuequanshu(景岳全書) that involves Yinyangpian(陰陽篇), Liubianbian(六變辨), Biaozhengpian(表證篇), Lizhengpian(裏證篇), Xushipian(虛實篇), and Hanrepian(寒熱篇), secondly, Cheng Guo-Peng's Yixuexinwu(醫學心悟) Hanrexushibiaoliyinyangbian(寒熱虛實表裏陰陽辨), at lastly Jiang Han-Tun's Bihuayijing(筆花醫鏡) Biaolixushihanreyinyangbian(表裏虛實寒熱辨). Results : All of sick cases can be explained totally by Eight Principle Patterns. Of Eight Principle Patterns, Yin(陰) and Yang(陽) include last Six Principle Patterns(六綱 : 表裏, 寒熱, 虛實). Six Principle Patterns can be divided normally by 6 pulses(六脈 : 浮沈 遲數 虛實). In all of pain cases, feeling comfortable(可按) or discomfortable(拒按) to palpation can be important foundation for distinguishing Xu(虛) from Shi(實). Physical constitution(體質) for Hanre Xushi(寒熱 虛實) and tongue-diagnosis(舌診) for Biaoli Hanre(表裏 寒熱) are used effectively. Related with tongue-diagnosis, tongue-coating(舌苔) for Biaoli and tongue status(舌質) for Hanre are used effectively. Symptoms should be divided following this sequence, Biaoli ${\rightarrow}$ Hanre ${\rightarrow}$ Xushi and lastly should be summarized of Yinyang. Conclusion : Diagnosing with Eight Principle Patterns, digestive function, urine, and feces should be checked at first. In addition, the pulse, tongue, physical constitution, and good or bad from palpation(觸診), these should be checked and give a result. And then the result can be an important evidence of syndrome differentiation. As a result, it would be the best to diagnosis that discriminating the sequence as Biaoli Hanre Xushi and summarizing with Yinyang.

• 한국기계가공학회지
• /
• 제20권2호
• /
• pp.51-57
• /
• 2021

The quality of the ceramic sintered coating on a metal surface through laser surface treatment is affected by the laser irradiation pattern. Depending on the laser irradiation pattern, the amount of residual stress and heat applied or accumulated on the surface increases or decreases, affecting the thickness attained in the ceramic sintering area. When the heat energy accumulated in the sintering area is high, the ceramic and the metal alloy melt and sufficiently mix to form a homogeneous and thick bonding interface. In this study, the thermal energy accumulation in the region sintered with zirconia was controlled using four types of laser processing patterns. The thickness of the diffusion region is analyzed by laser-induced breakdown spectroscopy of Mg-ZrO2 generated by laser sintering zirconia powder on the magnesium alloy surface. On the basis of the analysis of the Mg and Zr present in the sintered region through LIBS, the effect of the irradiation pattern on the sintering quality is confirmed by comparing and analyzing the heat and mass transfer tendency of the diffusion layer and the degree of diffusion according to the irradiation pattern. The derived diffusion coefficients differed by up to 9.8 times for each laser scanning pattern.

• 한국유체기계학회 논문집
• /
• 제11권5호
• /
• pp.50-56
• /
• 2008

Metal cutting operations involve generation of heat due to friction between the tool and the pieces. This heat needs to be carried away otherwise it creates white spots. To reduce this abnormal heat cutting fluid is used. Cutting fluid also has an important role in the lubrication of the cutting edges of machine tools and the pieces they are shaping, and in sluicing away the resulting swarf. As a cutting fluid, water is a great conductor of heat but is not stable at high temperatures, so to improve stability an emulsion type mixed fluid with water and oil is often used. It is pumped over the cutting site of cutting machines as a state of atomized water droplet coated with oil by using jet. In this paper, to develop cutting fluid supplying nozzle to obtain ultra thin oil film for coating water droplet, a numerical analysis of three dimensional mixed fluid Jet through multi-stage nozzle was carried out by using a finite volume method. Jet flow characteristics such as nozzle exit velocity, development of mixing region, re-entrance and jet intensity were analyzed. Detailed mixing process of fluids such as air, water and oil in the nozzle were also investigated. It is easy to understand complex flow pattern in multi-stage nozzle. Important flow Information for advance design of cutting fluid supplying nozzle was drawn.

• 농약과학회지
• /
• 제8권4호
• /
• pp.319-324
• /
• 2004

실리카 중공 미세구를 이용하여 방출 조절형 입제 농약을 제조합에 있어 실리카 중공 미세구 제조시 핵 제거 방법으로 열분해법을 사용하면 benfuracarb를 실리카 중공 미세구 중량의 2.67배까지 함침이 가능하였다. 이렇게 제조된 방출 조절형 입제 농약을 수중 방출 실험한 결과, 점결제로 ESO를 사용하였을 때 일정한 benfuracarb 방출 속도를 유지하여 10일부터 용액 중의 benfuracarb의 농도를 1.65 ppm 정도를 30일까지 유지되었다.

• Journal of Pharmaceutical Investigation
• /
• 제22권3호
• /
• pp.211-217
• /
• 1992

Stabilization of liposomes against degradation by bile salts has been investigated in order to develop a liposomal model system for oral drug delivery. Two polysaccharides, amylopectin (AP) and chitin (CT), were employed to coat both empty liposomes and bromthymol blue (BTB)-encapsulated liposomes by adsorption-coating techniques. Turbidity changes and BTB-release characteristics in pH 5.6 buffer solutions with or without bile salts, sodium cholate and sodium glycocholate, were observed to compare the differences between uncoated liposomes and polysaccharide-coated liposomes. Initial turbidities of both uncoated and polysaccharide-coated liposomes in buffer solution were kept constant within 3% range during 4 hours of experiments. But they were decreased in a different manner in bile salts-containing buffer solutions, showing 10% or less decrease for polysaccharide-coated liposomes and 25% or more decrease for uncoated liposomes. BTB release from uncoated liposomes has been greatly increased upto 90% after 4 hours in bile salts-containing buffer solution, which is a clue for breakdown of liposomal vesicles. However, polysaccharide-coated liposomes showed the controlled-release pattern which is proportional to square-root of time, followed by around 50% release for the same time period. Consequently, it is possible to conclude that these polysaccharide-coated liposomes might be an available system for oral delivery of a drug which is unstable in gut environment.

• 한국가구학회지
• /
• 제22권3호
• /
• pp.239-243
• /
• 2011

In this study, the coating properties and surface performance of exotic cherry wood (Prunus serotina) were estimated, reviewing color difference, hardness and abrasion resistibility in order to evaluate probability as construction interior members such as wall and floor. The reduction effect of color difference was represented in the order of water soluble color stain, water soluble transparent stain, and non-coated lumber. However, the tendency of distinct difference according to wood grain pattern was not found. The wavy grain lumber showed better properties in hardness and resistance to abrasion than quarter grain. In conclusion, it was supposed that the application of wavy grain lumber in wall and floor as interior materials would be acceptable in practicality.

• 한국기계가공학회지
• /
• 제10권6호
• /
• pp.146-151
• /
• 2011

Wax spin coating is a part of several wafer handling processes in the silicon wafer polishing station. It is important to ensure the wax layer free of contamination to achieve the high degree of planarization on wafers after wafer polishing. Three-dimensional air flow characteristics in a wax spin coater are numerically investigated using computational fluid dynamics techniques. When the bottom of the wax spin coater is closed, there exists a significant recirculation zone over the rotating ceramic block. This recirculation zone can be the source of wax layer contamination at any rotational speed and should be avoided to maintain high wafer polishing quality. Thus, four air suction ducts are installed at the bottom of the wax spin coater in order to control the air flow pattern over the ceramic block. Present computational results show that the air suction from the bottom is quite an effective method to remove or minimize the recirculation zone over the ceramic block and the wax coating layer.