• Title/Summary/Keyword: 1001

Search Result 521, Processing Time 0.026 seconds

Performance Comparison in Estimating the Number of Competing Terminals in IEEE 802.11 Networks (Kalman vs. H Infinity Filter) (IEEE 802.11 시스템에서 경쟁 터미널 수 추정기법 성능분석 (칼만필터 vs. H Infinity Filter))

  • Kim, Taejin;Lim, Jaechan;Hong, Daehyoung
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.37A no.11
    • /
    • pp.1001-1011
    • /
    • 2012
  • In this paper, the effects to system performance are evaluated in IEEE 802.11 system when the number of competing terminals are estimated and reflected to the system. The IEEE 802.11 system uses DCF (Distributed Coordination Function) for the multiple access method, and the system throughput performance depends on the accuracy of the estimated number of competing terminals. We propose extended H infinity filter (EHIF) approach which does not require the noise information for estimating the number of competing terminals. Simulation results show that EHIF outperforms the extended Kalman filter in both saturated and non-saturated network conditions.

Patterns of Anger Expression among Middle-aged Korean Women: Q methodology

  • Lee, Yong Mi;Kim, Geun Myun
    • Journal of Korean Academy of Nursing
    • /
    • v.42 no.7
    • /
    • pp.1001-1008
    • /
    • 2012
  • Purpose: The purpose of this study was to identify the characteristics of anger expression in middle-aged Korean women by categorizing their patterns of expression while considering the complexity and multidimensionality of anger, and by investigating the characteristics relative to the patterns. Methods: The research design was a descriptive design using Q methodology, which is a method of measuring subjectivity. A convenience sample of 42 participants aged 40-60 years and living in the community in Korea was recruited. The PC-QUANL software program (a factor analysis program for the Q technique) was used to analyze the Q-sort data. Results: Four factors were extracted that described different expressions of anger among middle-aged Korean women; these factors explained 50.1% of the total variance. The frames of reference of the four factors were a) direct diversion, b) silent masking with remaining anger, c) self digestion, and d) controlling anger with objectification. Conclusion: In this study has identified patterns and characteristics of anger expression among middle-aged Korean women were identified, which will aid the development of effective anger-management programs for controlling anger in this population. In future studies, it would be helpful to investigate how the patterns of anger expression established herein are associated with specific health problems such as cardiovascular disorder and cancer.

A Study on the Robust Optimal Supporting Positions of TFT-LCD Glass Panel (TFT-LCD 용 유리기판의 강건 최적 지지 위치의 선정에 관한 연구)

  • Huh Jae-Sung;Jung Byung-Chang;Lee Tae-Yoon;Kwak Byung-Man
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.8 s.251
    • /
    • pp.1001-1007
    • /
    • 2006
  • In this paper we present robust optimal supporting positions for large glass panels used for TFT-LCD monitors when they are stored in a cassette during manufacturing process. The criterion taken is to minimize their maximum deflection. Since they are supported by some supports and have large deformations, contact analysis with a geometrically nonlinear effect is necessary. In addition, the center of a panel can not be positioned exactly as intended and should be considered as uncertainties. To take into account of these effects, the mean and the standard deviation of system response functions, particularly the deflection of the panels, need be calculated. A function approximation moment method (FAMM) is utilized to estimate them. It is a special type of response surface methodology for structural reliability analysis and can be efficiently used to estimate the two stochastic properties, that is, the system performance and the perturbations caused by uncertainties. For a design purpose, they are to be minimized simultaneously by some optimization algorithm to obtain robust optimal supporting positions.

Reducing Separation Force for Projection Stereolithography based on Constrained Surface Technique (규제액면기법의 전사방식 광조형 시스템을 위한 이형력 감소)

  • Kim, Hye Jung;Ha, Young Myoung;Park, In Baek;Kim, Min Sub;Jo, Kwang Ho;Lee, Seok Hee
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.9
    • /
    • pp.1001-1006
    • /
    • 2013
  • Projection-based stereolithography is divided into constrained-surface and free-surface type according to controlling liquid layer. The constrained-surface type has a uniform layer thickness due to the use of a projection window, which covers the pattern generator such as liquid crystal display. However, the adhered resin on the projection window causes trouble and requires great separation force when the cured layer is separated from the window. To minimize the separation force, we developed a system to measure the separation force. The influence of material covering the pattern generator and the resin temperature is investigated in the system. Several structures according to the resin temperature and the velocity of z-axis elevation are compared. As a result, the fabrication condition to minimize the separation force reduces the process time.

Dye-sensitized Solar Cells with Mesoporous TiO2 Film Manufactured by Spin Coating Methode (스핀코팅법에 의해 제조되어진 나노다공질 TiO2 전극막을 이용한 염료감응형 태양전지)

  • 구보근;이동윤;이원재;김현주;송재성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.17 no.9
    • /
    • pp.1001-1005
    • /
    • 2004
  • Rye-sensitized solar cell (DSSC) is a new class of solar cell, which consists of nanoporous TiO$_2$ electrode, dye-sensitizer, electrolyte, and counter electrode. Such cell is operated in sunlight via the principle of photosynthetic electrochemistry. In order to obtain the good dispersion of nano size TiO$_2$ particles In slurry, the pH of solvent, the sort and quantify of solvent additive and the quantity of surfactant were adjusted. As results, the lower the pH of solvent was the lower the viscosity of the slurry became. The addition of ethylene glycol and propylene glycol to dilute HNO$_3$ brought about the lowering of viscosity and the enhancement of stability in slurry. The addition of surfactant lowered the viscosity of slurry. It was possible to obtain the homogeneous and uniformly dispersed mesoporous TiO$_2$ film using the dilute HNO$_3$ solvent of pH 2 with the addition of ethylene glycol and neutral surfactant. DSSC was assembled with TiO$_2$ electrode and Pt electrode, and its photoelectric property was measured using the monochromatic wavelength in the rangee of 350∼700 nm.

Establishment for Regulation Standards of Architectural Facility Noise Using Psycho-acoustic Experiment (청감실험을 이용한 건축 설비소음의 규제기준 설정)

  • Ju, Duck-Hoon;Yun, Jae-Hyun;Kim, Jae-Soo
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.20 no.11
    • /
    • pp.1001-1008
    • /
    • 2010
  • The architectural, facility makes the housing environment more pleasant, while too much noise coming from machinery room is detrimental to the workers physically and mentally. Therefore, more sound insulation and sound proof policies are increasingly required. However, as the annoyance caused by facility noise is influenced by various human listening characteristics as well as physical characteristics such as sound pressure level, it requires subjective evaluation characteristics through acoustic-psychological approach. For this purpose, the facility noise in the machinery room was actually measured and analyzed in the field to understand physical characteristics, and the correlation between physical evaluation value and psychological response value through listening test. Further, this study aims at presenting the data to set the standards of 'Just noticeable difference' of the facility noise together with reasonable evaluation with psychological reaction, through the grading of facility noise using trend formula. In the result, 13 stages of physical properties were forecasted for each evaluation method, together with 'Just noticeable difference' using the grading of architectural facility noise.

A Stacked Polusilicon Structure by Nitridation in N2 Atmosphere for Nano-scale CMOSFETs (나노 CMOS 소자 적용을 위한 질소 분위기에서 형성된 질화막을 이용한 폴리실리콘 적층 구조)

  • Ho, Won-Joon;Lee, Hi-Deok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.18 no.11
    • /
    • pp.1001-1006
    • /
    • 2005
  • A new fabrication method is proposed to form the stacked polysilicon gate by nitridation in $N_2$ atmosphere using conventional LP-CVD system. Two step stacked layers with an amorphous layer on top of a polycrystalline layer as well as three step stacked layers with polycrystalline films were fabricated using the proposed method. SIMS profile showed that the proposed method would successfully create the nitrogen-rich layers between the stacked polysilicon layers, thus resulting in effective retardation of dopant diffusion. It was observed that the dopants in stacked films were piled-up at the interface. TEM image also showed clear distinction of stacked layers, their plane grain size and grain mismatch at interface layers. Therefore, the number of stacked polysilicon layers with different crystalline structures, interface position and crystal phase can be easily controlled to improve the device performance and reliability without any negative effects in nano-scale CMOSFETs.

Considering the scrambling code of the line Study on the New Korea joint protection Standard Hangul character (회선부호의 스크램블링을 고려한 새로운 한국표준 한글글자마디부호에 관한 연구)

  • Park, Yo-Seph;Hong, Wan-Pyo
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.10 no.12
    • /
    • pp.1345-1354
    • /
    • 2015
  • This paper, information communication code standard($KS{\times}1001$, confirmation in 2004), as definded in Hangul Character Code Hangul AMI/HDB-3 the code set for the new system Hangul consonant and vowel tables presented. The result of the existing system and the code set ($4{\times}4$) bit source coding rules for comparing the frequency of use Hangul consonant and vowel tables(The National Institute of The Korea Language) and statistices showed that 44% of the data processing efficiency is improved.

Size-dependent bending analysis of FGM nano-sinusoidal plates resting on orthotropic elastic medium

  • Kolahchi, Reza;Bidgoli, Ali Mohammad Moniri;Heydari, Mohammad Mehdi
    • Structural Engineering and Mechanics
    • /
    • v.55 no.5
    • /
    • pp.1001-1014
    • /
    • 2015
  • Bending analysis of functionally graded (FG) nano-plates is investigated in the present work based on a new sinusoidal shear deformation theory. The theory accounts for sinusoidal distribution of transverse shear stress, and satisfies the free transverse shear stress conditions on the top and bottom surfaces of the plate without using shear correction factor. The material properties of nano-plate are assumed to vary according to power law distribution of the volume fraction of the constituents. The size effects are considered based on Eringen's nonlocal theory. Governing equations are derived using energy method and Hamilton's principle. The closed-form solutions of simply supported nano-plates are obtained and the results are compared with those of first-order shear deformation theory and higher-order shear deformation theory. The effects of different parameters such as nano-plate length and thickness, elastic foundation, orientation of foundation orthtotropy direction and nonlocal parameters are shown in dimensionless displacement of system. It can be found that with increasing nonlocal parameter, the dimensionless displacement of nano-plate increases.

Anomaly Detection System of IoT Platform using Machine Learning (기계학습을 활용한 IoT 플랫폼의 이상감지 시스템)

  • Im, SeonYeol;Choi, HyoKeun;Yi, KyuYull;Lee, TeaHun;Yu, HeonChang
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2018.10a
    • /
    • pp.1001-1004
    • /
    • 2018
  • As the industry generates a lot of data, it is increasingly dependent on the IoT platform. For this reason, the performance and anomaly detection of IoT platform is becoming an important factor. In this paper, we propose a system model of IoT platform that detects device anomaly without performance issue. The proposed system uses Micro Batch which calculates the data transmission cycle to provide Soft Real-time service. In the industry, it was difficult to collect abnormal data, so the Hotelling's $T^2$ model was applied to the data analysis experiment. And the Hotelling's $T^2$ model successfully detected anomalies.