• Title/Summary/Keyword: window effects

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Effects of Substrate Temperature on the Microstructure and Photoluminescence Properties of ZnO Thin Films by Atomic Layer Deposition (ZnO 성장을 위한 Atomic Layer Deposition법에서 공정온도가 박막의 구조적 및 광학적 특성에 미치는 영향)

  • Lim, Jong-Min;Lee, Chong-Mu
    • Korean Journal of Materials Research
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    • v.15 no.11
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    • pp.741-744
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    • 2005
  • Atomic layer deposition (ALD) is a very promising deposition technique for ZnO thin films. However, there have been very few reports on ZnO grown by ALD. Effects of substrate temperature in both ALD and post annealing on the microstructure and PL properties of ZnO thin films were investigated using X-ray diffraction, photoluminescence, and scanning electron microscopy. The temperature window of ALD is found to be between $130-180^{\circ}C$. The growth rate of ZnO thin film increases as the substrate temperature increases in the temperature range except the temperature window. The crystal quality depends most strongly on the substrate temperature among all the growth parameters of ALD. The crystallinity of the film is improved by increasing the growth thine per ALD cycle or doing post-annealing treatment. The grain size of the film tends to increase and the grain shape tends to change from a worm-like longish shape to a round one as the annealing temperature increases from $600^{\circ}C\;to\;1,000^{\circ}C$.

A Smoothing Data Cleaning based on Adaptive Window Sliding for Intelligent RFID Middleware Systems (지능적인 RFID 미들웨어 시스템을 위한 적응형 윈도우 슬라이딩 기반의 유연한 데이터 정제)

  • Shin, DongCheon;Oh, Dongok;Ryu, SeungWan;Park, Seikwon
    • Journal of Intelligence and Information Systems
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    • v.20 no.3
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    • pp.1-18
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    • 2014
  • Over the past years RFID/SN has been an elementary technology in a diversity of applications for the ubiquitous environments, especially for Internet of Things. However, one of obstacles for widespread deployment of RFID technology is the inherent unreliability of the RFID data streams by tag readers. In particular, the problem of false readings such as lost readings and mistaken readings needs to be treated by RFID middleware systems because false readings ultimately degrade the quality of application services due to the dirty data delivered by middleware systems. As a result, for the higher quality of services, an RFID middleware system is responsible for intelligently dealing with false readings for the delivery of clean data to the applications in accordance with the tag reading environment. One of popular techniques used to compensate false readings is a sliding window filter. In a sliding window scheme, it is evident that determining optimal window size intelligently is a nontrivial important task in RFID middleware systems in order to reduce false readings, especially in mobile environments. In this paper, for the purpose of reducing false readings by intelligent window adaption, we propose a new adaptive RFID data cleaning scheme based on window sliding for a single tag. Unlike previous works based on a binomial sampling model, we introduce the weight averaging. Our insight starts from the need to differentiate the past readings and the current readings, since the more recent readings may indicate the more accurate tag transitions. Owing to weight averaging, our scheme is expected to dynamically adapt the window size in an efficient manner even for non-homogeneous reading patterns in mobile environments. In addition, we analyze reading patterns in the window and effects of decreased window so that a more accurate and efficient decision on window adaption can be made. With our scheme, we can expect to obtain the ultimate goal that RFID middleware systems can provide applications with more clean data so that they can ensure high quality of intended services.

Measurement of Reflection Coefficient of Sound Absorbent Material with Respect to Angle of Incidence and Its Associated Errors (입사각에 따른 흡음재의 반사 계수 측정 방법론 및 오차에 대한 고찰)

  • 이수열;김상렬;김양한
    • Journal of KSNVE
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    • v.4 no.3
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    • pp.295-305
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    • 1994
  • The reflection coefficient of a material at oblique incidence is measured in a free field. The sound pressure distributions are measured at discrete points on two measurement lines and then decomposed into plane wave components by using spatial Fourier transform. The inciedent and reflected plane wave components are obtained from a set of "decomposition equations" of which uses the plane wave propagation theory. Numerical simulations and experiments have been performed to see the effect of finite size of measurement area. To reduce this effect, a window fuction has been performed to see the effects of finite size of mesurement area. To reduce this effect, a window function has been proposed and its effect on the measurement of sound absorbing material property has been studied as well. The reflection coefficient obtained by this method is compared with those obtained from other methods; 2-microphone method in a duct and an expirical equation of which determines the characteristic impedance .rho.c and propagation constant k of a material from flow resistance information.formation.

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Surgical Treatment of Post-pneumonectomy Empyema Thoracis (전폐절제 수술후 발생한 농흉치험)

  • 이두연
    • Journal of Chest Surgery
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    • v.24 no.6
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    • pp.555-559
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    • 1991
  • Post-pneumonectomy empyema thoracis is an uncommon, but very serious problem. Early diagnosis & adequate drainage followed by thoracoplasty and or myoplasty are very important principles for the management of the empyema thoracis & will enable patient to recover from the toxic effects. During the period of January, 1985 to December, 1990, 13 patients with post-pneumonectomy empyema thoracis were treated in the department of Thoracic and Cardiovascular Surgery, Yonsei University College of Medicine. There were 10 males % 3 females ranging from 31 years to 79 years of age. The occurrence ratio of left to right side was 8: 5. The underlying pathologic lesions of empyema thoracis were pulmonary tuberculosis[7], lung ca. [2] pneumothorax[2], lung abscess[1] pneumonia[1]. We treatment procedure for post-pneumonectomy empyema thoracis were open window thoracostomy in 10 cases, Clagett procedures in 2 cases, one thoracoplasty, and two cases of Clagett procedures followed by open window thoracostomy in one cases.

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Optical Noise Removal in the Focal Plane of the Spaceborne Camera

  • Park, Jun-Oh;Jang, Won-Kweon;Kim, Seong-Hui;Jang, Hong-Sul;Lee, Seung-Hoon
    • Journal of the Optical Society of Korea
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    • v.15 no.3
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    • pp.278-282
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    • 2011
  • We discuss two possible optical noise sources in an electro-optic camera loaded on a low earth orbit satellite. The first noise source was a reflection at the window for signal rays incident upon the window which is placed before the FPA plane. The second noise source came from a reflection at the surface of the FPA cell when the signal flux is not entirely absorbed. We investigate the noise generation processes for two optical noise sources, and a parametric solution is used to estimate the optical noise effects.

Study on Reduction of Forklift's Booming Noise (지게차 부밍소음 저감에 대한 연구)

  • Park, S.T.;Kim, G.H.;Lee, J.K.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1487-1492
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    • 2000
  • To identify forklift's booming noise in cabin under idling engine revolution, we discussed and applied conditioned input analysis. Acceleration signals at engine mounts and front window and rear window were considered as candidate input signals and output signal was sound pressure signal at driver's ear position in cabin. To reduce the numbers of the input signals, one idea were applied; Each one input signal from each input groups was selected, respectively because input signals in the same group were highly correlated. And Hilbert transform was used to determine the ordering of three selected inputs. Partial coherence functions, multiple coherence function and conditioned spectral density functions were investigate to the effects of booming noise by partial inputs.

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A Study on the Characterization of Fire Plume Ejected from an Opening according to the Opening Form and the Balcony of Apartment in Korea (국내 공동주택의 개구부형태 및 발코니 유·무에 따른 분출화염 성상에 관한 연구)

  • Lee, Kyu-Min;Koo, Tae-Yoon;Hwang, Eu-Cheong;Kwon, Young-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.05a
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    • pp.37-38
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    • 2017
  • This study identified the effects of flame on the upper by fire plume ejected. we implemented model experiment according to investigation of housing area effect, window aspect ratio and balcony availability. we confirmed that opening ratio was increased according to housing area larger. the square window confirmed that is progressing fire plume ejected of free space. According to the value of an opening aspect ratio 'n' getting higher, the horizontal widow is getting that increased the risk as the fire spread an external to the top of opening. it is determined to the fundamental solution about fire safety in the extended balcony of apartment.

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Review on Pre-processing of Earthquake Data from KEPRI Seismic Monitoring System (전력연구원 지진관측자료의 사전자료처리 기법 및 효과적인 활용에 관한 고찰)

  • 연관희;박동희;최원학;장천중
    • Journal of the Earthquake Engineering Society of Korea
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    • v.6 no.2
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    • pp.39-50
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    • 2002
  • Several pre-processing techniques for earthquake data from earthquake monitoring institutes in Korea including Korea Electric Power Research Institute are thoroughly reviewed. Among these techniques for removing an instrumental response, removing the non-causal ringing distortion by FIR filter, checking calibration status of seismic stations, and minimizing the window effect are introduced and applied to real data. It is also recommended that analysts evaluate S/N ratio in the frequency domain and consider the possibility of using the saturated earthquake data.

Improved Memory Characteristics by NH3 Post Annealing for ZrO2 Based Charge Trapping Nonvolatile Memory

  • Tang, Zhenjie;Zhao, Dongqiu;Li, Rong;Zhu, Xinhua
    • Transactions on Electrical and Electronic Materials
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    • v.15 no.1
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    • pp.16-19
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    • 2014
  • Charge trapping nonvolatile memory capacitors with $ZrO_2$ as charge trapping layer were fabricated, and the effects of post annealing atmosphere ($NH_3$ and $N_2$) on their memory storage characteristics were investigated. It was found that the memory windows were improved, after annealing treatment. The memory capacitor after $NH_3$ annealing treatment exhibited the best electrical characteristics, with a 6.8 V memory window, a lower charge loss ~22.3% up to ten years, even at $150^{\circ}C$, and excellent endurance (1.5% memory window degradation). The results are attributed to deep level bulk charge traps, induced by using $NH_3$ annealing.

The Influence of Unattended Distractors on the Identification of Targets (주의하지 않은 방해자극이 표적의 식별에 미치는 영향)

  • Park, ChangHo
    • Korean Journal of Cognitive Science
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    • v.24 no.4
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    • pp.365-391
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    • 2013
  • Negative repetition effect (NRE) refers to the phenomenon that the accuracy of report is impaired when a target was flanked by the same distractor than when by alternative distractor. To probe the nature of NRE, this study introduced attention window(s) indicating the positions where a target might be presented, and non-attention window(s) where a target could not be presented. Attention windows are supposed to help participants detect targets readily. Two among three positions are indicated by attention windows in Exp. 1, and a single large attention window encompassing central two positions among four positions was used in Exp. 2, and either large or small attention window was used depending on the number of target candidates in Exp. 3. In the result of three experiments, NREs were consistently observed when both positions of a target and a distractor were indicated by previous attention windows. However, NREs (including its tendency) and its opposite, PREs were observed when a distractor was presented in the non-attention position, depending on its distance from the target and the size of attention window. It seems that this pattern of repetition effects is hard to be explained by repetition blindness hypothesis (Kanwisher, 1991), positional uncertainty hypothesis (Keren & Boer, 1985), and inhibitory attention capture hypothesis (Kwak et al., 1993). Instead it was proposed that shifting of spatial attention should be considered accordingly with the structure of stimulus display. The promising role of this task was discussed in studying the relation of attention and perception.

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