• International journal of advanced smart convergence
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• 제12권1호
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• pp.70-75
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• 2023

With the recent proliferation of memory-intensive workloads such as deep learning, analyzing memory access characteristics for efficient memory management is becoming increasingly important. Since read and write operations in memory access have different characteristics, an efficient memory management policy should take into accountthe characteristics of thesetwo operationsseparately. Although some previous studies have considered the different characteristics of reads and writes, they require a modified hardware architecture supporting read bits and write bits. Unlike previous approaches, we propose a software-based management policy under the existing memory architecture for considering read/write characteristics. The proposed policy logically partitions memory space into the read/write area and the write area by making use of reference bits and dirty bits provided in modern paging systems. Simulation experiments with memory access traces show that our approach performs better than the CLOCK algorithm by 23% on average, and the effect is similar to the previous policy with hardware support.

• 대한임베디드공학회논문지
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• 제13권5호
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• pp.261-268
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• 2018

Phase Change Memory(PCM) with low power consumption and high integration attracts attention as a next generation nonvolatile memory replacing DRAM. However, there is a problem that PCM has long latency and high energy consumption due to the writing operation. The PCM & DRAM hybrid memory structure is a fruitful structure that can overcome the disadvantages of such PCM. However, the page replacement algorithm is important, because these structures use two memory of different characteristics. The purpose of this document is to effectively manage pages that can be referenced in memory, taking into account the characteristics of DRAM and PCM. In order to manage these pages, this paper proposes an page replacement algorithm based on frequently accessed and recently paged. According to our simulation, the proposed algorithm for the DRAM&PCM hybrid can reduce the energy-delay product by around 10%, compared with Clock-DWF and CLOCK-HM.

• Transactions on Electrical and Electronic Materials
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• 제15권1호
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.19-19
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• 2008

We investigated the programmable memory characteristics of nanoparticle-based memory devices based on the elementary metal nanoparticles (Co and Au) and their binary mixture synthesized by a micellar route to ordered arrays of metal nanoparticles as charge trapping layers. According to the metal nanoparticle species quite different programming/erasing efficiencies were observed, resulting in the tunable memory characteristics at the same programming/erasing bias conditions. This finding will be a good implication for further device scaling and novel device applications since most processes are based on the conventional semiconductor processes.

• 디지털산업정보학회논문지
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• 제5권4호
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• pp.169-177
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• 2009

In come cases, people differently respond on the same joke or thoughtless behavior - sometimes like it and laugh, another time feel annoyed or angry. This fact is explained that experiences which we had in the past are remembered by emotional memory, so they cause different responses. When people face similar situation or feel similar emotion, they evoke the emotion experienced in the past and the emotional memory affects current emotion. This paper suggested the mechanism of the emotional memory using SOM through the similarity between the emotional memory and SOM learning algorithm. It was assumed that the mechanism of the emotional memory has also the characteristics of association memory, long-term memory and short-term memory in its process of remembering emotional experience, which are known as the characteristics of the process of remembering factual experience. And then these characteristics were applied. The mechanism of the emotional memory designed like this was applied to toy hammer game and I measured the change in the power of toy hammer caused by differently responding on the same stimulus. The mechanism of the emotional memory suggest in above is expected to apply to the fields of game, robot engineering, because the mechanism can express various emotions on the same stimulus.

• 재활간호학회지
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• 제10권2호
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• pp.134-140
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• 2007

Purpose: The purpose of this study was to find out relation of general characteristics and memory performance of old adults. Method: The subjects consisted of 160 old adults over the age 60 who living in Seoul. Data were collected by the interview method, using a structured questionnaire and the testing method on the memory performance. Data were analyzed by SPSS PC. Result: The level of memory performance is 63.0 points in the 84 point scale, immediate recall is 7.8 points in the 12 point scale, delayed recall is 7.6 points in the 12 point scale, word recognition is 16 points in the 24 point scale, & face recognition is 16 points in the 24 point scale, & face recognition is 26.8 points in the 40 point scale. Analysis of memory performance according to general characteristics showed that there were statistically differences for age, sex, religion and alcohol. Memory performance showed a significantly negative correlation with age and alcohol, but positive correlation with sex. The significant variables to predict old adults'memory performance are age and alcohol. Conclusion: The findings of this study give useful information for constructing an memory performance improving program based on general characteristics in old adults.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.833-836
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• 2001

The thermomechanical behaviors of the shape memory alloy were conducted through the finite element analysis of ABAQUS with UMAT user subroutine. The unified thermomechanical constitutive equation suggested by Lagoudas was adapted into the UMAT user subroutine to investigate the characteristics of the shape memory alloy. The three cases were solved to investigate the thermomechanical characteristics of the shape memory alloy. The material properties for the analysis were obtained by DSC and DMA techniques. According to the results, the thermomechanical characteristics, such as a shape memory effect and a pseudoelastic effect, could be obtained through the finite element analysis and the analysis results were revealed to agree well with the experimental results. Therefore, the finite element analysis using UMAT user subroutine is one of prominent analysis techniques to investigate the thermomechnical behaviors of the shape memory alloy quantitatively.

• 전자공학회논문지A
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• 제31A권3호
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• pp.28-39
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• 1994

We experimented on memory multichip modules to increase the packing density of memory devices and to improve their electrical characteristics. A 128K$\times$8bit SRAM module was made of four 32K$\times$8bit SRAM memory chips. The memory multichip module was constructed on a low-cost double sided PCB(printed circuit boared) substrate. In the process of fabricating a multichip module. we focused on the improvement of its electrical characteristics. volume, and weight by employing bare memory chips. The characteristics of the bare chip module was compared with that of the module with four packaged chips. We conducted circuit routing with a PCAD program, and found the followings: the routed area for the module with bare memory chips reduced to a quarter of that area for module with packaged memory chips. 1/8 in volume, 1/5 in weight. Signal transmission delay times calculated by using transmission line model was reduced from 0.8 nsec to 0.4 nsec only on the module board, but the coupling coefficinet was not changed. Thus, we realized that the electrical characteristics of multichip packages on PCB board be improved greatly when using bare memory chips.

• 한국산학기술학회논문지
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• 제15권8호
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• pp.5213-5218
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• 2014

유기메모리 제작을 위해 플라즈마 중합법에 의해 절연박막, 터널링 박막을 제작하였고, Au 메모리박막을 이용하여 플로팅게이트형 유기메모리를 제작하였다. 플로팅 게이트형 유기메모리의 메모리층의 전하충전 및 방전에 따른 유기메모리 동작특성을 생각해 보았고, 이를 증명하고자 게이트전압에 따른 히스테리전압 및 메모리전압을 측정하였다. 그 결과 게이트 전압의 인가에 따른 메모리층의 동작 이론을 증명하고자 게이트전압이 증가함에 따른 소스-드레인 전류의 히스테리시스 현상이 심해지는 것을 확인하였고, -60~60[V]전압 인가시 26[V]의 큰 히스테리시스 전압값을 보였다. 또한 게이트 전극에 쓰기전압인가에 따른 현상을 본 결과, 60[V]의 쓰기 전압을 인가하였을 시 13[V]의 memory 전압을 나타내었고, 80[V]의 쓰기전압을 인가하였을 시 18[V]로 memory 전압이 약 40[%] 향상된 수치를 보였다. 이로부터 메모리층의 전하 충전 및 방전에 따른 메모리 동작특성 이론을 실험적으로 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1137-1138
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• 2011

This paper deals with the PM performance evaluations in a pole changing memory motor (PCMM) using a coupled transient finite element method (FEM) and Preisach modeling, which is presented to analyze the magnetic characteristics of permanent magnets. The focus of this paper is the characteristics evaluation relative to magnetizing direction and the pole number of machine on re-, demagnetization condition in a pole changing memory motor.