• 한국컴퓨터정보학회논문지
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• 제25권11호
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• pp.83-88
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• 2020

본 논문에서는 진보된 프리앰블 탐지 기술인 MIM을 무선 센서 노드에 적용하는 방안을 제시한다. 또한 MIM 기능을 탑재한 센서 노드들이 IEEE 802.15.4 방식의 센서와 경쟁할 경우 발생할 수 있는 처리량과 공정성 사이의 트레이드오프 관계를 분석한다. MIM 센서들은 IEEE 802.15.4 기반의 센서에 비해 추가적인 동시전송 기회를 가져 처리량 측면에서 이득이 생기는 반면 IEEE 802.15.4 방식의 센서 노드들은 MIM 센서 노드들의 동시다발적인 추가 전송으로 인해 전송 기회를 제한받는다. 성능 평가를 위해 파이썬으로 시험환경을 구축하고 상용 센서 노드의 설정값을 반영하여 모의시험을 수행한 결과 MIM을 적용한 경우 최대 40% 수준의 처리량 향상을 확인하였다. 한편 동시전송 임계값을 적절히 조절함으로써 처리량과 공정성 측면에서 균형을 맞출 수 있음을 확인하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제23권1호
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• pp.225-246
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• 2014

With the recent establishment of a ubiquitous environment and the paradigm shift to a smart society, the use of mobile devices, such as smart phones and tablet PCs, has become widespread. Thus, the trend is gradually shifting from using Web-based Instant Messenger to using Mobile-based Instant Messenger. Mobile Instant Messenger refers to a service that allows instant messaging as well as data sending and receiving between individuals with exclusive application programs(mobile Apps), which can be used in portable devices-such as smart phones-with wireless Internet access. Korea's portal sites, telecommunication companies, and even big companies have all rushed into the MIM market to join the competition. The reason so many companies are showing interest in the MIM business is because it is rising as a core platform to substitute portal sites in the mobile society, and MIM is perceived as the best means to attract and secure users. The intention to reuse or use continually was considered an important factor in maintaining a dominant position amidst such fierce competition, and consequently, most research thus far has reflected such thought. However, the frequent or long-term use of a system alone cannot indicate the definite success of the system, nor guarantee its dominant position in the market. On the contrary, MIM dependence, which goes beyond simple repetitive use and indicates a state where users actually or emotionally depend on a specific system, can better explain the user action. However, not much research has been conducted on dependence. The research results showed that lively message, concise message, message responsiveness, and social belonging significantly affected perceived usefulness. Message responsiveness, Link, and social belonging significantly affected flow. Flow significantly affected MIM dependence, and perceived usefulness did not affect MIM dependence. This study has proven that lively message, concise message, message responsiveness, Link, social belonging and perceived usefulness are important antecedents and mediating factors of MIM dependence. Moreover, this study is significant in that it explains the overall process of MIM dependence, and expands on the variety and scope of research that can be applied to MIM-related studies.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.221-222
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• 2006

This paper describes a Plasma Assisted Debinding and Sintering (PADS) equipment, which has been designed to process Metal Injection Molded (MIM) components. The use of a hybrid system combining a glow discharge with a conventional heating system makes debinding and sintering of MIM components, in the same heating cycle, a feasible industrial process. Characteristics as density, carbon content and mechanical properties are similar to traditionally processed MIM materials. The reduction of energy and gas consumption and shorter lead-times are economic advantages of PADS system. The clean environment of PADS is also an ecological advantage.

• 멤브레인
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• 제31권3호
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• pp.219-227
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• 2021

분자각인막(MIM)은 특정 분자의 결합자리를 갖고 있는 다공성 고분자 막이다. 비용매유도 상분리(NIPS)법을 사용하여 분자각인막의 지지체로 사용될 P(AN-co-MA) 비대칭막을 제조하고, 여기에 표면 각인법을 적용하여 광활성 이니퍼터 도입과 photo-grafting을 통해 라이소자임 분자각인막을 제조하였다. P(AN-co-MA) 비대칭막을 3-chloropropyltrimethoxysilane과 광활성 이니퍼터 dithiocarbamate로 개질하고, acrylamide 단량체, N,N'-methylenebisacrylamide 가교제, 라이소자임 주형분자 혼합액을 UV 조사 환경에서 혼성중합 시켜 MIM을 제조하였다. 제조된 MIM의 FT-IR과 FE-SEM 및 EDS 분석을 실시한 결과 P(AN-co-MA) 막은 비대칭 단면 구조이었고 표면에 이니퍼터 그룹이 잘 결합되어 있어 MIM이 성공적으로 제조되었다. 제조공정의 변수 조절을 통해 라이소자임의 흡착량이 비각인막(NIM)에 비해 13배 큰 값인 2.7 mg/g을 갖는 P(AN-co-MA) 기반 MIM이 제조되었으며, 막여과 실험을 통해 라이소자임에 대한 오발부민의 투과선택도를 측정한 결과 MIM은 라이소자임의 선택적 결합력이 우수하였다.

• 대한기계학회논문집B
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• 제34권2호
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• pp.99-103
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• 2010

다공성 매질상에서 유체와 용질의 이동은 Mobile zone과 Immobile zone으로 분리해서 분석하는 Mobile-Immobile Zone Model을 이용하여 쉽게 현상을 구현할 수 있었으나 본 연구에서는 2차원 4각형태의 pore 상에서 확산주도영역(Immobile zone)으로 들어가고 나오는 용질의 확산에 관한 새로운 Analytic solution을 유도하여 기존 MIM Zone model과 비교 분석하였다. 새롭게 유도된 Analytic solution은 기존의 MIM model 과 비교했을때 충분히 오랜시간이 경과한 후에는 해의 일치를 보이지만 MIM model의 경우 초기 농도값이 주입된 실제 농도보다 약 20 % 낮게 나타난다. Mass-transfer 계수, $\alpha$는 일반적으로 시간의 흐름에 따라 감소하게 되는데 일정 시간이 경과하게 되면 안정화 되고 일정함을 유지하며 그 시간은 무차원으로 약 ${\tau}_0=0.15$이다. 또한 $\alpha$는 분자확산과 비례하며 Immobile 영역의 깊이와 반비례하는 반면 작은 시간이 경과한 후에는 시간에 종속되어진다.

• Current Optics and Photonics
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• 제7권2호
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• pp.136-146
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• 2023

Based on calculations using the macroscopic Maxwell's equations with mesoscopic boundary conditions, light absorption by a layered metal-insulator-metal (MIM) metamaterial system embedded in three different environments is investigated. Increasing the top metal thickness shifts the broad absorption band to lower dielectric-constant regions and longer wavelengths, for either TM or TE waves. Boosting the dielectric-layer thickness redshifts the broadband absorption to regions of larger dielectric constant. In air, for the dielectric-constant range of 0.86-3.40, the absorption of the system exceeds 98% across 680-1,033 nm. In seawater with optimized dielectric constant, ≥94% light absorption over 400-1,200 nm can be achieved; particularly in the wavelength range of 480-960 nm and dielectric-constant range of 0.82-3.50, the absorption is greater than 98%. In an environment with even higher refractive index (1.74), ≥98% light absorption over 400-1,200 nm can be achieved, giving better performance. The influence of angle of incidence on light absorption of the MIM system is also analyzed, and the angle tolerance for ≥90% broadband absorption of a TM wave is up to 40° in an environment with large refractive index. While the incident-angle dependence of the absorption of a TE wave is nearly the same for different circumstances, the situation is different for a TM wave.

• 한국정보시스템학회지:정보시스템연구
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• 제25권3호
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• pp.61-90
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• 2016

Purpose Recently the usage of Mobile Instant Messenger(MIM) has been increased all over the world. With the development of Mobile Internet, a large amount of mobile application came into being, such as WeChat, the most popular MIM now in China. It has a huge number of registered users, but just only half of them are the "active users". This study intends to examine what factors affect MIM user's continuance intention and actual usage behavior. Design/Methodology/Approach Based on the framework of Perception/Emotion-Behavior and the extended ECM-ISC (Expectation Confirmation Model of IS Continuance), this research introduced some unique variables to a user satisfaction model focusing on perceived/emotional factors in WeChat. In this model, perceived/emotional factors have been divided into enabler factors and inhibitor factors to analyze the effect on continuance intention and actual usage behavior. Also, the moderate effect of the habits was discussed. An online questionnaire survey of 203 WeChat users was conducted and the empirical validation was employed to test the research model. Findings From the empirical results, perceived usefulness, expectation confirmation, and needs for affiliation significantly affected satisfaction. Also, satisfaction influenced continuance intention which led to actual usage behavior. We found that the habit moderates the relationship between satisfaction and continuance intention. The result of this study provides guidance to the developers and operators of WeChat on how to improve enhance users' satisfaction and loyalty.

• 센서학회지
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• 제16권2호
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• pp.97-103
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• 2007

Crystallized carbon nitride film that has many stable physical and/or chemical properties has been expected potentially by a new electrical material. However, one of the most significant problems degrading the quality of carbon nitride films is an existence of N-H and C-H bonds from the deposition environment. The possibility of these reactions with hydroxyl group in carbon nitride films, caused by a hydrogen attack, was suggested and proved in our previous reports that this undesired effect could be applied for fabricating micro-humidity sensors. In this study, MIS capacitor and MIM capacitor with $5{\mu}m{\times}5{\mu}m$ meshes were fabricated. As an insulator, carbon nitride film was deposited on a $Si_{3}N_{4}/SiO_{2}/Si$ substrate using reactive magnetron sputtering system, and its dielectric constant, C-V characteristics and humidity sensing properties were investigated. The fabricated humidity sensors showed a linearity in the humidity range of 0 %RH to 80 %RH. These results reveal that MIS and MIM $CN_{X}$ capacitive humidity sensors can be used for Si based micro-humidity sensors.

• Transactions on Electrical and Electronic Materials
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• 제10권5호
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• pp.147-151
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• 2009

For integrated passive device (IPD) applications, we have successfully developed and characterized metalinsulator-metal (MIM) capacitors with 2000 $\AA$ plasma-enhanced chemical vapor deposition (PECVD) silicon nitride which are deposited with the $SiH_4/NH_3$ gas mixing rate, working pressure, and RF power of PECVD at $250^{\circ}C$. Five PECVD process parameters are designed to lower the refractive index and lower the deposition rate of $Si_3N_4$ films for the high breakdown electric field. For the PECVD process condition of gas mixing rate (0.957), working pressure (0.9 Torr), and RF power (60 W), the atomic force microscopy (AFM) root mean square (RMS) value of about 2000 $\AA$ $Si_3N_4$ on the bottom metal is lowest at 0.862 nm and the breakdown electric field is highest at about 8.0 MV/cm with a capacitance density of 326.5 pF/$mm^2$. A pretreatment of metal electrodes is proposed, which can reduce the peeling of nitride in the harsh test environment of heat, pressure, and humidity.

• 에너지공학
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• 제19권4호
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• pp.240-245
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• 2010

화석연료는 사용 후 재생이 불가능하고 매장량이 한정되어 있으며, 연소 시 발생되는 각종 공해물질로 인해 환경문제를 야기하고 있다. 이러한 맥락에서 차세대 청정대체에너지로서 주목을 받고 있는 것이 바로 수소에너지이다. 현재 가장 경제성이 있는 수소제조방법으로 알려진 천연가스 Steam Reformig(SRM)은 천연가스의 매장량 한계성으로 인해 그 제조비용이 높아지고 있어, 바이오매스 및 유기성 폐기물의 가스화를 통한 수소생산방법이 자원의 재순환, 페기물 처리, 열원의 이용, 직접적인 $CO_2$ 삭감 등의 부수적인 효과가 높아 경제성 있는 수소제조법으로 많은 연구가 진행되고 있다. 이에 본 연구에서는 잠재적으로 고갈 염려가 있는 화석연료를 대체하고, 화석연료의 연소 시 발생되는 환경문제를 해결하고자 열분해로와 고온개질기로 구성된 Pilot-scale Two Stage Gasifier를 개발하고, 본 장치 내에서의 biomass의 가스화 특성을 평가하고자 한다. 열분 해로에서의 가스화 실험 결과, 열분해로의 전환율은 약 70%로 나타났으며, $H_2$, $CH_4$, CO, $CO_2$의 평균 생성량은 각각 16.7, 11.3, 37.2, 26.6 L/mim의 결과를 보였다. 고온개질기로부터의 생성가스 수율의 결과로부터, 고온개질기에 적용된 $1100^{\circ}C$의 초고온에서의 개질 반응에 의해 $CH_4$의 대부분이 환원됨을 확인할 수 있었다. 본 연구로부터 개발된 장치의 냉가스 효율은 53.2%로 비교적 높은 결과가 얻어졌으며, 수소에 대한 평균 생성량은 55.4 L/min의 결과를 보였다.