• Title/Summary/Keyword: transition-edge

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Smart Factory Activation Plan through Analysis of Smart Factory Promotion Status and Introduction Plan Data

  • Seong-Hoon Lee
    • International journal of advanced smart convergence
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    • v.13 no.2
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    • pp.229-234
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    • 2024
  • A smart factory is defined as a cutting-edge, intelligent factory that integrates all production processes from product planning to sales with information and communication technology. Through these factories, each company produces customized products with minimal cost and time. The smart factory promotion project in Korea has produced positive results even in difficult environments such as the COVID-19 situation. Through the transition to a smart manufacturing production system, the competitiveness of small and medium-sized businesses has been greatly strengthened, including increased productivity and reduced costs. This study was based on surveyed data conducted by organizations related to smart factory promotion in 2020. Significant contents and major characteristics that emerged from the surveyed data were inferred and described. Since the meaningful contents reflect the reality of the company, more efficient promotion of smart factories will be possible in the future.

Implementation of Roughness-Induced Turbulent Transition Model on Inflight Icing Code (표면 조도를 고려한 난류 천이 모델의 항공기 결빙 해석자에 대한 적용 연구)

  • Min, Seungin;Yee, Kwanjung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.1
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    • pp.23-33
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    • 2020
  • In this study, the effect of surface roughness distribution and its influence on the inflight icing code was investigated. Previous numerical studies focused on the magnitude of surface roughness, and the effects were only addressed in terms of changes in thermal boundary layers with fully turbulent assumption. In addition, the empirical formula was used to take account the turbulent transition due to surface roughness, which was regarded as reducing the accuracy of ice shape prediction. Therefore, in this study, the turbulent transition model based on the two-equation turbulence model was applied to consider the effects of surface roughness. In order to consider the effect of surface roughness, the transport equation for roughness amplification parameter was applied, and the surface roughness distribution model was implemented to consider the physical properties. For validation, the surface roughness, convective heat transfer coefficient, and ice shape were compared with experimental results and other numerical methodology. As a result, it was confirmed that the excessive prediction of the heat transfer coefficient at the leading edge and the ice horn shape at the bottom of the airfoil were improved accordingly.

Photo-Induced Scalar Phenomena according to Thickness Dependence of Chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ Thin Film (칼코게나이트 $As_{40}Ge_{10}Se_{15}S_{35}$ 박막에서 두께에 따른 광유기 스칼라 현상)

  • 이현용;박수호;정홍배
    • Electrical & Electronic Materials
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    • v.10 no.5
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    • pp.467-472
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    • 1997
  • In this study, we investigated the thickness dependence of thermal bleaching(TB) effect as well as photo-induced scalar phenomena, such as photodrakening(PD) effect and photorefraction(PR) change, in chalcogenide A $s_{40}$ G $e_{10}$S $e_{15}$ $S_{35}$ thin films. We found that when these films were exposed for 15 minutes using blue-pass filtered Hg lamp(~4300$\AA$) after annealing for 30 minutes around the glass transition temperature Tg(20$0^{\circ}C$), the refractive index change ($\Delta$n) was varied up to 0.02~0.46 according to each thickness condition and the optical energy gap ($\Delta$ $E_{op}$ ) was shifted to a longer wavelength of approximately 0.67eV, especially for 1000$\AA$-thickness. Also, the TB PD effects have been understood by the results related to optical absorption characteristics. The TB effect could be estimated as increasing the stabilization of amorphous chalcogenide films since absorption slope of extended regions(U) was not changed by annealing. On the other hand, the PD effect could be understood as due to the enhancement of disorder since U and the slope of Urbachs tail(1/F) around an absorption edge were decreased by exposing.ing.n edge were decreased by exposing.

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A DPLL with a Modified Phase Frequency Detector to Reduce Lock Time (록 시간을 줄이기 위한 변형 위상 주파수 검출기를 가진 DPLL)

  • Hasan, Md. Tariq;Choi, GoangSeog
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.10
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    • pp.76-81
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    • 2013
  • A new phase frequency detector based digital phase-locked loop (PLL) of 125 MHz was designed using the 130 nm CMOS technology library consisting of inverting edge detectors along with a typical digital phase-locked loop to reduce the lock time and jitter for mid-frequency applications. XOR based inverting edge detectors were used to obtain a transition earlier than the reference signal to change the output more quickly. The HSPICE simulator was used in a Cadence environment for simulation. The performance of the digital phase-locked loops with the proposed phase frequency detector was compared with that of conventional phase frequency detector. The PLL with the proposed detector took $0.304{\mu}s$ to lock with a maximum jitter of approximately 0.1142 ns, whereas the conventional PLL took a minimum of $2.144{\mu}s$ to lock with a maximum jitter of approximately 0.1245 ns.

Dehydration Characteristics of Cationic Surfactant-Modified Montmorillonite (양이온성 계면활성제로 표면개질된 몬모릴로나이트의 탈수 특성)

  • Seung Yeop Lee;Soo Jin Kim
    • Journal of the Mineralogical Society of Korea
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    • v.15 no.4
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    • pp.305-314
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    • 2002
  • The dehydration of hexadecyltrimethylammonium (HDTMA)-exchanged montmorillonite has been studied using X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). The dehydration in HDTMA-montmorillonite seems to influence the swelling behavior of the organo-clay during heating. The basal d(001) spacing vs temperature curve of the HDTMA-montmorillonite has one broad swelling edge with a shoulder on the low-temperature side. We believe that the shoulder at $100^{\circ}C$ for the HDTMA-montmorillonite is due to interlayer swelling induced by the initial rearrangement of surfactants, and the second edge at $200^{\circ}C$ is caused by interlayer swelling resulting from the secondary vertical reorientation of alkyl chains. It seems that the dehydration of organo-clay induces a reorientation of the alkyl chains by transition to more vertical position relative to the silicate sheets, allowing instantly greater d-spacing.

Motion Areas based Painterly Animation using Various Edges (다양한 에지를 이용한 모션영역 기반 회화적 애니메이션)

  • Park, Young-Sup;Yoon, Kyung-Hyun
    • Journal of the Korea Computer Graphics Society
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    • v.14 no.1
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    • pp.1-10
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    • 2008
  • In this paper, we present a novel method for creating a hand-painted painterly animation, starting from a video input. One of the most important aspects in painterly animation is to maintain the temporal coherence of brush strokes between frames, which plays a vital role to warrant a smooth transition between frames. Our unique utilization of motion areas enables users to produce a smooth movement of brush strokes. The motion areas are the parts where objects move between frames and they are categorized in two main types. A strong motion area is the part where the movement of real edges and hidden edges is determined by the motion vector between frames. The real edge is the outline of an object and the hidden edge is the boundary to represent the direction of a grain of intensity in the areas with gradations. A weak motion area is the remainder after subtracting the strong motion area from the entire motion area. Temporally coherent painterly animation is achieved by re-painting the brush strokes on the canvas using two motion areas, resulting in a natural and hand-painted appearance.

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Nanostructure of Optical Materials Doped with Rare-Earths: X-Ray Absorption Spectroscopy of Dy-Doped Ge-As-S Glass (희토류 첨가 광소재의 나노구조 : Dy 첨가 Ge-As-S 유리의 X-선 흡수 스펙트럼 분석)

  • Choi, Yong-Gyu;Song, Jay-Hyok;Shin, Yong-Beom;Chernov, Vladimir A.;Heo, Jong
    • Journal of the Korean Ceramic Society
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    • v.43 no.3 s.286
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    • pp.177-184
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    • 2006
  • Dy $L_3$-edge XANES and EXAFS spectra of chalcogenide Ge-As-S glass doped with ca. 0.2 wt% dysprosium have been investigated along with some reference Dy-containing crystals. Amplitude of the white-line peak in XANES spectrum of the glass sample turns out to be stronger than that of other reference crystals, i.e., $DY_2S_3,\;Dy_2O_3\;and\;DyBr_3$. It has been verified from the Dy $L_3$-edge EXAFS spectra that a central Dy atom is surrounded by $6.7{\pm}0.5$ sulfur atoms in its first coordination shell in the Ge-As-S glass, which is relatively smaller than 7.5 of the $Dy_2S_3$ crystal. Averaged Dy-S inter-atomic-distance of the glass ($2.78{\pm}0.01{\AA}$) also turns out to be somewhat shorter than that of the $Dy_2S_3$ crystal ($2.82{\pm}0.01{\AA}$). Such nanostructural changes occurring at Dy atoms imply there being stronger covalency of Dy-S chemical bonds in the Ge-As-S glass than in the crystal counterpart. The enhanced covalency in the nanostructural environment of $Dy^{3+}$ ions inside the glass would then be responsible for optical characteristics of the $4f{\leftrightarrow}4f$ transitions of the dopants, i.e., increase of oscillator strengths and spontaneous radiative transition probabilities.

Investigation of Research Trends in the D(Data)·N(Network)·A(A.I) Field Using the Dynamic Topic Model (다이나믹 토픽 모델을 활용한 D(Data)·N(Network)·A(A.I) 중심의 연구동향 분석)

  • Wo, Chang Woo;Lee, Jong Yun
    • Journal of the Korea Convergence Society
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    • v.11 no.9
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    • pp.21-29
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    • 2020
  • The Topic Modeling research, the methodology for deduction keyword within literature, has become active with the explosion of data from digital society transition. The research objective is to investigate research trends in D.N.A.(Data, Network, Artificial Intelligence) field using DTM(Dynamic Topic Model). DTM model was applied to the 1,519 of research projects with SW·A.I technology classifications among ICT(Information and Communication Technology) field projects between 6 years(2015~2020). As a result, technology keyword for D.N.A. field; Big data, Cloud, Artificial Intelligence, extended keyword; Unstructured, Edge Computing, Learning, Recognition was appeared every year, and accordingly that the above technology is being researched inclusively from other projects can be inferred. Finally, it is expected that the result from this paper become useful for future policy·R&D planning and corporation's technology·marketing strategy.

Boost Type ZVS-PWM Chopper-Fed DC-DC Power Converter with Load-Side Auxiliary Resonant Snubber and Its Performance Evaluations

  • Ogura, Koki;Chandhaket, Srawouth;Ahmed, Tarek;Nakaoka, Mutsuo
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • v.3B no.3
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    • pp.147-154
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    • 2003
  • This paper presents a high-frequency boost type ZVS-PWM chopper-fed DC-DC power converter with a single active auxiliary edge-resonant snubber at the load stage which can be designed for power conditioners such as solar photovoltaic generation, fuel cell generation, battery and super capacitor energy storages. Its principle operation in steady-state is described in addition to a prototype setup. The experimental results of boost type ZVS-PWM chopper proposed here, are evaluated and verified with a practical design model in terms of its switching voltage and current waveforms, the switching v-i trajectory and the temperature performance of IGBT module, the actual power conversion efficiency, and the EMI of radiated and conducted emissions, and then discussed and compared with the hard switching scheme from an experimental point of view. Finally, this paper proposes a practical method to suppress parasitic oscillation due to the active auxiliary resonant switch at ZCS turn-off mode transition with the aid of an additional lossless clamping diode loop, and can be reduced the EMI conducted emission.

Spectroscopic Studies on the High-$T_c$ Superconducting $La_2CuO_{4-δ}$ Prepared by Electrochemical Oxidation

  • 박정철;Alain Wattiaux;Jean-Claude Grenier;김동훈;최진호
    • Bulletin of the Korean Chemical Society
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    • v.18 no.9
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    • pp.916-922
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    • 1997
  • A superconducting phase La2CuO4+δ (Tc=44 K) has been prepared by electrochemical oxidation which allows the oxygen to intercalat into the La2O2 layers. According to the Cu K-edge X-ray absorption near edge structure spectroscopic analysis, the oxidized phase shows an overall spectra shift of about 0.5 eV to a higher energy region compared to the as sintered one with the occurrence of an additional peak corresponding to the transition to the |1s13dn+1L-14pσ1 > final state, indicating the oxidation of CuO2 layer. From the X-ray photoelectron spectroscopic studies, it is found that the binding energy of La 3d5/2 is significantly shifted from 834.3 eV (as sintered La2CuO4) to 833.6 eV (as electrochemically oxidized La2CuO4+δ), implying that the covalency of the (La-O) bond is decreased due to the oxygen intercalation. The O 1s spectra do not provide an evidence of the superoxide or peroxide, but the oxide (O2-) with the contaminated carbonate (CO32-) based on the peaks at 529 eV and 532 eV, respectively, which is clearly confirmed by the Auger spectroscopic analysis. Oxygen contents determined by iodometric titration (δ=0.07) and thermogravimetry (δ=0.09) show good coincidence each other, also giving an evidence for the "O2-" nature of excess oxygen. From the above results, it is concluded that "O2-" appeared as O 1s peak at 528.6 eV is responsible for superconductivity of La2CuO4+δ.