• Title/Summary/Keyword: field annealing

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Parameter estimation of mean field annealing technique for optimal boundary smoothing (최적의 Boundary Smoothing을 위한 Mean Field Annealing 기법의 파라미터 추정에 관한 연구)

  • Kwa
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.1
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    • pp.185-192
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    • 1997
  • We propose a method of paramete estimation using order-of-magnitude analysis for optimal boundary smoothing in Mean Field Annealing(MFA) technique in this paper. We previously proposed two boundary smoothing methods for consistent object representation in the previous paper, one is using a constratined regulaization(CR) method and the other is using a MFA method. The CR method causes unnecessary smoothing effects at corners. On the other hand, the MFA method method smooths our the noise without losing sharpness of corners. The MFA algorithm is influenced by several parameters such as standard deviation of the noise, the relativemagnitude of prior ter, initial temperature and final temperature. We propose a general parameter esimation method for optimal boundary smoothing using order-of-magnitude analysis to be used for consistent object representation in this paper. In addition, we prove the effectiveness of our parameter estimation and also show the temperature parameter sensitivities of the algorithm.

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3-D Object Recognition Using A Mean Field Annealing Neural Network (Mean Field Annealing 신경회로망을 이용한 3차원 물체인식)

  • 이양렬;박래홍
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.5
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    • pp.78-87
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    • 1999
  • 3차원 물체 인식은 학습에 의해서 구성된 모델베이스를 이용하여 주어진 입력 영상에 존재하는 한 개 혹은 여러 개의 물체를 구별하는 과정이다. 본 논문에서는 입력 거리 정보를 받아들여 이 정보로부터 보이는 각 면에 대한 특징을 추출해낸 후 이 특징들을 입력 영상에 존재하는 물체를 묘사하는 특징으로 사용하여 이로부터 모델을 결정하는 방법을 제시한다. 영상 분할된 입력 물체는 그래프로 표현되는데, 물체 인식은 입력 물체의 그래프를 모델 베이스의 각 모델의 그래프와 정합하는 고정에서 얻어진다. 제한 조건은 만족시키는 정합을 수행하기 위하여 mean field annealing (MFA) 신경 회로망을 사용하였으며 가려진 물체 인식을 수행할 수 있는 정합을 위해 에너지 함수를 제안하였다. 제안한 알고리듬의 효용성을 입증하기 위하여 가려짐의 정도를 다르게 한 합성영상에 대해서 모의 실험을 하였다.

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Characteristics of Amorphous Fe-based Thin Firms with Low Core Losses (저손실 Fe-계 비정질 박막의 자기적 특성)

  • 민복기;김현식;송재성;허정섭;오영우
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.633-636
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    • 1999
  • In this study, we have fabricated amorphous FeZrBAg thin films with low core losses by using DC magnetron sputtering method. After deposition, rotational field annealing (RFA) method was performed in the dc field of 1.5 kOe. The amorphous FeZrBAg thin films produced by annealing at 35$0^{\circ}C$ was founded to have high permeability of 8680 at 100 MHz, 0.2 mOe, low coercivity of 0.86 Oe high magnetization of 1.5 T and very low core loss of 1.3 W/cc at 1 MHz, 0.IT respectively. Excellent soft magnetic properties in a amorphous FeZrBAg thin films in the present study are presumably the homogeneous formation of very fine bcc $\alpha$-Fe crystalline with the 8.2 nm in an amorphous FeZrBAg thin film matrix.

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The Effects of Heat-treatment on Magnetic Properties for Gas-atomized MPP Dust Cores (가스분무법으로 제조한 MPP 분말코어의 자기적 특성에 미치는 열처리 효과)

  • 노태환;김구현;김광윤;정인범;최광보
    • Journal of the Korean Magnetics Society
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    • v.11 no.4
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    • pp.173-178
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    • 2001
  • The effects of heat-treatment with magnetic or non-magnetic field on magnetic properties of gas-atomized MPP dust cores subjected to various cooling processes after annealing were investigated. Upon magnetic-field annealing, ac permeability and core loss decreased with the increase of cooling rate, which were attributed to the generation of inhomogeneous internal stress and anomalous eddy current loss, respectively. It was not observed the formation of ordered phase and the related change in magnetic properties at the cooling stage for MPP dust cores. In MPP alloys, magnetic anisotropy was easily induced through the directional order, and permeability and core loss were changed under the conditions of low cooling rate and magnetic annealing.

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A Load Balancing Technique Combined with Mean-Field Annealing and Genetic Algorithms (평균장 어닐링과 유전자 알고리즘을 결합한 부하균형기법)

  • Hong Chul-Eui;Park Kyeong-Mo
    • Journal of KIISE:Computer Systems and Theory
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    • v.33 no.8
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    • pp.486-494
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    • 2006
  • In this paper, we introduce a new solution for the load balancing problem, an important issue in parallel processing. Our heuristic load balancing technique called MGA effectively combines the benefit of both mean-field annealing (MFA) and genetic algorithms (GA). We compare the proposed MGA algorithm with other mapping algorithms (MFA, GA-l, and GA-2). A multiprocessor mapping algorithm simulation has been developed to measure performance improvement ratio of these algorithms. Our experimental results show that our new technique, the composition of heuristic mapping methods improves performance over the conventional ones, in terms of solution quality with a longer run time.

Effects of Rapid Thermal Annealing on Thermal Stability of FeMn Spin Valve Sensors

  • Park, Seung-Young;Choi, Yeon-Bong;Jo, Soon-Chul
    • Journal of Magnetics
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    • v.10 no.2
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    • pp.52-57
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    • 2005
  • In this research, magnetoresistance (MR) ratio (MR), resistivity, and exchange coupling field $(H_{ex})$ behaviors for sputter deposited spin valves with FeMn antiferromagnetic layer have been extensively investigated by rapid thermal annealing (RTA) as well as conventional annealing (CA) method. 10 s of RTA revealed that interdiffusion was not significant up to $325^{\circ}C$ at the interfaces between the layers when the RTA time was short. The MR of FeMn spin valves were reduced when the spin valves were exposed to temperature of $250^{\circ}C$, even for a short time period of 10 s prior to CA. $H_{ex}$ was maintained up to $325^{\circ}C$ of CA when the specimen was subjected to 10 s of RTA at $200^{\circ}C$ prior to CA, which is $25^{\circ}C$ higher than the result obtained from the CA without prior RTA. Therefore, the stability of $H_{ex}$ could be enhanced by a prior RTA before performing CA up to annealing temperature of $325^{\circ}C$. MR and sensitivity of the specimens annealed without magnetic field up to $275^{\circ}C$ were recovered to the values prior to CA, but $H_{ex}$ was not recovered. This means that reduced MR sensitivity and MR during the device fabrication can be recovered by a field RTA.

Variation of Asymmetric Hysteresis Loops with Annealing Temperature and Time (열처리 온도와 시간에 따른 비대칭 자기 이력 곡선의 변화)

  • 신경호;민성혜;이장로
    • Journal of the Korean Magnetics Society
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    • v.5 no.4
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    • pp.251-260
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    • 1995
  • It has been reported that Co-based amorphous ferromagnetic alloys annealed in a small magnetic field develop a reproducible, asymmetric hysteresis loop. If the direction of the field during annealing is regarded as +, the magnetization reversal from - to + is smooth and reversible, with its slope determined by the demagnetizing field of the sample. This phenomenon is called the asymmetric magnetization reversal (AMR). The shape of the hyster-esis loop depends sensitively on the condition during the anneal and the alloy composition. Here, we report on the effect of the annealing temperature and time on AMR in a zero magnetostrictive ferromagnetic amorphous alloy. The AMR effect develops in a very short time at a reasonably high temperature, but is stabilized by annealing for a prolonged time.

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Effects of Annealing on Electrical Characteristics of Double-Gated Silicon Nanosheet Feedback Field-Effect Transistors (더블게이트 실리콘 나노시트 피드백 전계효과 트랜지스터의 전기적 특성에 미치는 열처리 효과)

  • Hyojoo Heo;Yunwoo Shin;Jaemin Son;Seungho Ryu;Kyoungah Cho;Sangsig Kim
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.418-424
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    • 2023
  • In this study, we examined the effects of annealing on electrical characteristics of double-gated silicon nanosheet (SiNS) feedback field effect transistors (FBFETs). When bias stresses were applied for 1000 s, the double-gated SiNS FBFETs were more affected by positive bias stresses than negative bias stresses regardless of the channel mode owing to the increase of interface traps caused by electrons in the inversion layers. After annealing at 300 ℃ for 10 mins, the devices were completely recovered to their original properties, and the characteristics did not change anymore when bias stresses were applied again for 1000 s.

Effect of Annealing Time on Electrical Performance of SiZnSnO Thin Film Transistor Fabricated by RF Magnetron Sputtering

  • Ko, Kyung Min;Lee, Sang Yeol
    • Transactions on Electrical and Electronic Materials
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    • v.16 no.2
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    • pp.99-102
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    • 2015
  • Thin film transistors (TFTs) with amorphous 2 wt% silicon-doped zinc tin oxide (a-2SZTO) channel layer were fabricated using an RF magnetron sputtering system, and the effect of post-annealing treatment time on the structural and electrical properties of a-2SZTO systems was investigated. It is well known that Si can effectively reduce the generation of oxygen vacancies. However, it is interesting to note that prolonged annealing could have a bad effect on the roughness of a-2SZTO systems, since the roughness of a-2SZTO thin films increases in proportion to the thermal annealing treatment time. Thermal annealing can control the electrical characteristics of amorphous oxide semiconductor (AOS) TFTs. It was observed herein that prolonged annealing treatment can cause bumpy roughness, which led to increase of the contact resistance between the electrode and channel. Thus, it was confirmed that deterioration of the electrical characteristics could occur due to prolonged annealing. The longer annealing time also decreased the field effect mobility. The a-2SZTO TFTs annealed at 500℃ for 2 hours displayed the mobility of 2.17 cm2/Vs. As the electrical characteristics of a-2SZTO annealed at a fixed temperature for long periods were deteriorated, careful optimization of the annealing conditions for a-2SZTO, in terms of time, should be carried out to achieve better performance.