• Title/Summary/Keyword: Core Reflection

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Bragg Reflecting Waveguide Device Fabricated on a Flexible Substrate using a Nano-imprinting Technology (나노임프린팅 기술을 이용한 유연성 브래그 반사 광도파로 소자)

  • Kim, Kyung-Jo;Yi, Jeong-Ah;Oh, Min-Cheol
    • Korean Journal of Optics and Photonics
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    • v.18 no.2
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    • pp.149-154
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    • 2007
  • Bragg reflecting waveguide devices have been fabricated on a flexible polymer substrate utilizing a post lift-off process which could Provide excellent uniformity of grating Patterns on Plastic film. The 510 m Period Bragg grating pattern is made by two methods. In the first sample the grating is fabricated by exposing the laser interference pattern on a photoresist, and then it is inscribed by $O_2$ plasma etching. The grating pattern of the second sample is formed by a PDMS soft mold imprinting process. The selective adhesion property of SU-8 material for Au and Si surfaces is utilized to prepare a 100-mm thick plastic substrate. Single mode waveguide is fabricated on the plastic substrate using polymer materials with refractive indices of 1.540 and 1.430 for the core and the cladding layers, respectively. The Bragg grating on Plastic substrate does not show any degradation in its spectral response compared to the reference sample made on a silicon wafer.

A 10Gb/s Analog Adaptive Equalizer for Backplanes (백플레인용 10Gbps 아날로그 어댑티브 이퀄라이저)

  • Yoo, Kwi-Sung;Han, Gun-Hee;Park, Sung-Min
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.9
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    • pp.34-39
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    • 2007
  • Serial links via backplane channels suffer from severe signal integrity problems which are normally caused by channel imperfections, such as flat loss, frequency-dependent loss, reflection, etc. Particularly, the frequency-dependent loss causes ISI(Inter-Symbol-Interference) at signal waveforms. Therefore, adaptive equalizing techniques have been exploited in many products to facilitate the ISI problem. In this paper, we present an analog adaptive equalizer circuit designed in a $0.18{\mu}m$ CMOS process. It achieves 10Gb/s data transmission through a long 34-inch backplane channel(or transmission line). The post-layout simulations demonstrate $8ps_{p-p}$ jitter with 10mW power dissipation. The core of the adaptive equalizer occupies the area of $0.56mm^2$.

Gradient Structures and Surface Composition of Polypropylene/Ethylene-Propylene Rubber Blends (폴리프로필렌/에틸렌-프로필렌 고무 블렌드 경사구조 및 표면조성)

  • Kim, Seog Je;Lee, Sung-Goo;Lee, Jae Heung;Choi, Kil-Yeong
    • Journal of Adhesion and Interface
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    • v.2 no.4
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    • pp.24-31
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    • 2001
  • Polypropylenes(PP) with different melt index values were mixed with ethylene-propylene rubber(EPR) or ethylene-propylene diene monomer rubber(EPDM) and an ethylene copolymer containing carboxylic acid group in a twin screw extruder. Then test specimens were prepared from the pellets of the blends with an injection molding machine. The mechanical properties and morphology of fractured surfaces were measured. Relative peak intensities of carboxylic acid group on the specimen surface were measured with an attennuated total reflection infrared spectrometer (ATR-IR) and compared with each other. The blend specimens were found to have the gradient morphology of rubber domains in PP matrix in the core region and PP skin layer. The blends containing PP of higher melt index showed greater content of ethylene copolymer containing carboxylic acid on the surface when the relative peak intensities of ATR-IR for carboxylic acid were compared. As the melt index values were increased, the decrease tendency in mechanical propeties such as tensile strength and impact strength was more significant for PP/EPR blends than PP/EPDM blends.

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Electrical and Optical Properties of Transparent Conducting Films having GZO/Metal/GZO Hybrid-structure; Effects of Metal Layer(Ag, Cu, Al, Zn) (GZO/Metal/GZO 하이브리드 구조 투명 전도막의 전기적, 광학적 특성; Ag, Cu, Al, Zn 금속 삽입층의 효과)

  • Kim, Hyeon-Beom;Kim, Dong-Ho;Lee, Gun-Hwan;Kim, Kang-Ho
    • Journal of the Korean institute of surface engineering
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    • v.43 no.3
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    • pp.148-153
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    • 2010
  • Transparent conducting films having a hybrid structure of GZO/Metal/GZO were prepared on glass substrates by sequential deposition using DC magnetron sputtering. Silver, copper, aluminum and zinc thin films were used as the intermediate metal layers in the hybrid structure. The electrical and optical properties of hybrid transparent conducting films were investigated with varying the thickness of metal layer or GZO layers. With increasing the metal thickness, hybrid films showed a noticeable improvement of the electrical conductivity, which is mainly dependent on the electrical property of the metal layer. GZO(40 nm)/Ag(10 nm)/GZO(40 nm) film exhibits a resistivity of $5.2{\times}10^{-5}{\Omega}{\cdot}cm$ with an optical transmittance of 82.8%. For the films with Zn interlayer, only marginal reduction in the resistivity was observed. Furthermore, unlike other metals, hybrid films with Zn interlayer showed a decrease in the resistivity with increasing the GZO thickness. The optimal thickness of GZO layer for anti-reflection effect at a given thickness of metal (10 nm) was found to be critically dependent on the refractive index of the metal. In addition, x-ray diffraction analysis showed that the insertion of Ag layer resulted in the improvement of crystallinity of GZO films, which is beneficial for the electrical and optical properties of hybrid-type transparent conducting films.

The Study of Usability Evaluation Method for the Mobile Internet GUI -Based on design evaluation method development for improvement of Emotional satisfaction- (모바일 인터넷 표준 GUI 개발을 위한 사용성 평가 기술 연구 -감성만족도 향상을 위한 디자인 평가 기술 개발을 중심으로-)

  • 김종덕;정봉금
    • Archives of design research
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    • v.17 no.1
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    • pp.253-264
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    • 2004
  • The final goal of this research is development of graphic design evaluation methodology in elevation of a usability at the mobile internet services and of measurement model which can forecast user needs in interface design, and systemize evaluation basis. For this, we systemize core contents of GUI design evaluation methodology and embodied UI design support system that supports prototype layout and evaluation process directly. The sight language that can inform flow of controled information by the quick and implicated method so that user may complete task in a short time without overload of recognition in limited display environment of Small Screen device it must improve objectivity in the reflection of UI design with image. Thus evaluation methodology that can evaluate usability of mobile internet systematically is important and specially, graphic design evaluation model which can forecast user's design need and trend is meaningful because of special quality that can reflect sensitive aspect of user in interface design. Mobile internet GUI was done by the result of this design evaluation, and I hope this result can be utilized for the GUI development of Ubiquitous environment for the future research.

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Design and Evaluation of Intelligent Helmet Display System (지능형 헬멧시현시스템 설계 및 시험평가)

  • Hwang, Sang-Hyun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.5
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    • pp.417-428
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    • 2017
  • In this paper, we describe the architectural design, unit component hardware design and core software design(Helmet Pose Tracking Software and Terrain Elevation Data Correction Software) of IHDS(Intelligent Helmet Display System), and describe the results of unit test and integration test. According to the trend of the latest helmet display system, the specifications which includes 3D map display, FLIR(Forward Looking Infra-Red) display, hybrid helmet pose tracking, visor reflection type of binocular optical system, NVC(Night Vision Camera) display, lightweight composite helmet shell were applied to the design. Especially, we proposed unique design concepts such as the automatic correction of altitude error of 3D map data, high precision image registration, multi-color lighting optical system, transmissive image emitting surface using diffraction optical element, tracking camera minimizing latency time of helmet pose estimation and air pockets for helmet fixation on head. After completing the prototype of all system components, unit tests and system integration tests were performed to verify the functions and performance.

The Romance and Tragedy in Lee Chan's Poetry (이찬 시의 낭만성과 비극성)

  • Yoo, Sung Ho
    • Cross-Cultural Studies
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    • v.19
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    • pp.127-147
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    • 2010
  • Lee Chan's early poems were defined as the world of romance. His second-term poems were defined as proletarian poetry and poems written in prison when he made the romance as the core point through longing and desire for lost world. Maximizing the romance was proletarian poetry. His third-term poems were feelings of the northern countries called the spirit of Lee Chan's poems. He recognized the emotion of diaspora as the tragedy in these poems. It was remarkable time that the poet's tragedy observing and expressing the reality of colony. Afterward he wrote poems related inside withdrawal and war cooperation, finally he wrote poem after defecting to North Korea. Lee Chan showed the romance of desire in early poems and proletarian poems. Then he indicated acute scenery of the tragedy in the late 1930s' poems. In heavy situation, he moved from pro-Japanese literature to North Korean literature. However he didn't throw introspected self-reflection language to himself each his changing. But through several form of garden, he clearly showed consistent of maximizing his utopia sense. The time Lee Chan experienced was an icon which intensively indicated several features of deformed modern Korean poetic history. He was a unique poet who expressed various traces of modern Korean poetry in short time step by step. His path informed that he was a special poet who stepped the trace of many modern Korean poetry's extremes such as romantic poetry, proletarian poetry, prison poetry, pro-Japanese poetry and North Korean poetry. Likewise we can call his life as a grudge return. Because he left hometown, experienced the light and darkness of modern times and returned his hometown.

Qualitative evaluation of dental hygiene students following the application of the Capstone Design in dental hygiene theory and practice (일부 치위생학과 캡스톤 디자인 기반의 임상치위생학 수업 경험에 관한 질적 연구: 성찰일지 분석을 중심으로)

  • Choi, Yong-Keum;Jeon, Hyun-Sun;Park, Hyang-Ah
    • Journal of Korean Dental Hygiene Science
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    • v.4 no.2
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    • pp.77-88
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    • 2021
  • Background: In this study, the Capstone Design was applied to the clinical dental hygiene course of the Department of Dental Hygiene, and its effect was confirmed by qualitatively evaluating the students' reflection on the capstone design class experience. Methods: This study was conducted for the "Clinical Dental Hygiene and Practice III" course, in which third year students develop the ability to judge and plan dental hygiene based on problem-solving ability and critical thinking. By applying the Capstone Design within the core curriculum of the class, the students analyzed problems based on their major knowledge of dental hygiene in order to improve their ability to manipulate periodontal instruments, and focusedon the process of developing the contents of periodontal instruments by using them. Results: The application of Capstone Design on clinical dental hygiene and practice III classes increased students' active class participation, and through the problem-solving process, students' learning and confidence improved. Conclusion: The Capstone Design can be viewed as a teaching method that promotes the participation of students in the dental hygiene department and can effectively help their learning and confidence through a problem-solving process.

Research on the Development Direction of Language Model-based Generative Artificial Intelligence through Patent Trend Analysis (특허 동향 분석을 통한 언어 모델 기반 생성형 인공지능 발전 방향 연구)

  • Daehee Kim;Jonghyun Lee;Beom-seok Kim;Jinhong Yang
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.5
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    • pp.279-291
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    • 2023
  • In recent years, language model-based generative AI technologies have made remarkable progress. In particular, it has attracted a lot of attention due to its increasing potential in various fields such as summarization and code writing. As a reflection of this interest, the number of patent applications related to generative AI has been increasing rapidly. In order to understand these trends and develop strategies accordingly, future forecasting is key. Predictions can be used to better understand the future trends in the field of technology and develop more effective strategies. In this paper, we analyzed patents filed to date to identify the direction of development of language model-based generative AI. In particular, we took an in-depth look at research and invention activities in each country, focusing on application trends by year and detailed technology. Through this analysis, we tried to understand the detailed technologies contained in the core patents and predict the future development trends of generative AI.

A Study on the Resilience Process of Persons with Disabilities (중도장애인의 레질리언스(Resilience) 과정에 관한 연구)

  • Kim, Mi-Ok
    • Korean Journal of Social Welfare
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    • v.60 no.2
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    • pp.99-129
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    • 2008
  • This study analyzed the resilience process of persons with disabilities using the grounded theory approach. To conduct this study, the researcher conducted in-depth interviews with 8 persons with disabilities. In data analysis, this study identified 393 concepts on the resilience process of persons with disabilities and the concepts were categorized into 45 sub-categories and 18 primary categories. In the paradigm model on the resilience process of persons with disabilities, it was identified that casual conditions included 'unawareness of disability before being disability', 'extreme pain', 'repressing psychological pain', and the contingent conditions were 'dis-empowerment by staying in home', 'isolation by himself with difficulty in accepting the disability', 'experience of frustration from social barriers with prejudice against persons with disabilities'. Also, it was identified that the resilience process could be dependent on the type and the degree of the disability, the gender, and the length of time being disability. In spite of the casual and contingent conditions, the central way in which persons with disabilities could acquire resilience was identified as 'enhancement of the power of positive thinking'. The control conditions which accelerate or retard central phenomenon were 'the awareness of not being alone through family, friends, neighborhood and the social system' externally and 'finding purpose in life through religion and help from other persons with disabilities', internally. The action/interactional sequences enhanced the efforts, self searching and active acting, and as a result, persons with disabilities could find comfort in life, participate in society and change the perspective of disability in society. The core categories of resilience process in persons with disabilities were a belief in affirmation and choice of life by initiative. In the process analysis, stages developed in the following: 'pain', 'strangeness', 'reflection', 'daily life'. This stage was more continuous and causal than discrete and complete. In this process, the types of resilience of persons with disabilities are divided into 'existence reflection', 'course development', 'implicit endeavor', and 'active execution'. This study showed the details of the paradigm models, the process and types with an in-depth understanding of the resilience process of persons with disabilities using grounded theory as well as theory construction and policy and clinical involvement on the study of persons with disabilities.

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