• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.134-135
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• 2008

Ultra-thin $SiO_2/ZrO_2$ dielectrics were deposited by atomic layer chemical vapor deposition (ALCVD) method for non-volatile memory application. Metal-oxide-semiconductor (MOS) capacitors were fabricated by stacking ultra-thin $SiO_2$ and $ZrO_2$ dielectrics. It is found that the tunneling current through the stacked dielectric at the high voltage is lager than that through the conventional silicon oxide barrier. On the other hand, the tunneling leakage current at low voltages is suppressed. Therefore, the use of ultra-thin $SiO_2/ZrO_2$ dielectrics as a tunneling barrier is promising for the future high integrated non-volatile memory.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.243-244
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• 2006

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.97-103
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• 2010

There are many algorithms for 2D to 3D graphic conversion technology which have the high complexity and large scale of iterative computation. So in this paper propose parallel algorithm and high speed graphics accelerator architecture using Park's MAMS(Multiple Access Memory System) for Phong Shading, one of many 3D algorithms. The Proposed SIMD processor architecture is simulated by HDL and simulated and got 30 times faster result. It means any kinds of 3D algorithm can make parallel algorithm and accelerated by SIMD processor with Park's MAMS for real time processing.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.5
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• pp.476-484
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• 2015

Due to the recent advances in non-volatile memory technologies such as PCM, a new memory hierarchy of computer systems is expected to appear. In this paper, we explore the performance of PCM-based swap systems and discuss how this system can be managed efficiently. Specifically, we introduce three management techniques. First, we show that the page fault handling time can be reduced by attaching PCM on DIMM slots, thereby eliminating the software stack overhead of block I/O and the context switch time. Second, we show that it is effective to reduce the page size and turn off the read-ahead option under the PCM swap system where the page fault handling time is sufficiently small. Third, we show that the performance is not degraded even with a small DRAM memory under a PCM swap device; this leads to the reduction of DRAM's energy consumption significantly compared to HDD-based swap systems. We expect that the result of this paper will lead to the transition of the legacy swap system structure of "large memory - slow swap" to a new paradigm of "small memory - fast swap."

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.57-60
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• 1998

Lean zirconate titanate (PZT) is an attractive material for the memory device applications. We have investigated Pt and{{{{ { RuO}_{2 } }}}} as a botton electrode for a device application of PZT thin film. The bottom electrodes were prepared by using an RF magnetron sputtering method. The substrate temperature influenced the resistivity of Pt and {{{{ { RuO}_{2 } }}}} a s well as the film crystal structure. XRD examination shows that a preferred(111) orientations for the substrate temperature of 30$0^{\circ}C$. From the XRD and AFM results, we recommend the substrate temperature of 30$0^{\circ}C$ for the bottom electrode growth. We investigated and anneal temperature effect because Perovskite PZT structure is recommended for the memory device applications and the structural transformation is occurred only after and elevated heat treatment. As post anneal temperature was increased from RT to $700^{\circ}C$, the resistivity of Rt and {{{{ { RuO}_{2 } }}}} w as decreased. Surface morphology was observed by AFM as a function of post anneal temperature.

• Korean Journal of Cognitive Science
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• v.10 no.4
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• pp.41-50
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• 1999

It is widely known that the hippocampus plays an important role in spatial memory. Recent studies have suggested that the posterior parietal cortex (PPC) is involved in spatial memory. However it is unclear whether the PPC is involved in w working memory or reference memory of spatial learning. The purpose of the present study was to determine contribution of the hippocampus and the PPC to spatial working memory and acquisition of reference memory. Using an eight-arm radial maze in which e each arm was baited. working memory was tested by measuring rat's ability to remember arms they had visited. Reference memory was tested by measuring rat's ability to avoid visiting four consistently unbaited arms. Effects of hippocampal or PPC lesion on working memory or acquisition of reference memory in radial-arm maze learning were investigated Working memory was impaired by hippocampal lesion whereas not affected by PPC lesion. Acquisition of reference memory was impaired by lesion in either site. The results suggest that the hippocampus plays an important role in the spatial working memory while both the hippocampus and the PPC contribute to the acquisition of spatial reference memory.

• Journal of Drive and Control
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• v.6 no.2
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• pp.34-39
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• 2009

• The KIPS Transactions:PartA
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• v.11A no.7 s.91
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• pp.475-482
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• 2004

We live in the flood of information due to advancement of information communication and increase of E-mail. Managing users huge in-formation systematically and speedy searching are needed in these social advancement. In this thesis, in order to satisfy these requirement, We suggested Real-time LDAP Interface using Main Memory Resident Database Management System which can manage a lot of information fast systematically. It is expected that system can provide advantage of performance improvement through replacing Main Memory Resident Database Management System without change of application which is required high speed process.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.38 no.1
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• pp.26-45
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• 2001

The Flash memory market: is an exciting market that has quickly over the last 10 years. Recently Flash memory provides a high-density. truly non-volatile, high performance read write memory solutions, also is characterized by low power consumption, extreme ruggedness and high reliability. Flash memory is an optimum solution for large nonvolitilc storage operations such as solid file storage, digital video recorder, digital still camera, The MP3 player and other portable multimedia communication applications requiring non-volatility. Regardless of the type of Flash memory, Flash media management software is always required to manage the larger Flash memory block partitions. This is true, since Flash memory cannot be erased on the byte level common to memory, but must be erased on a block granularity. The management of a Flash memory manager requires a keen understanding of a Flash technology and data management methods. Though Flash memory's write performance is relatively slow, the suggested algorithm offers a higher maximum write performance. Algorithms so far developed is not suitable for applications which is requiring more fast and frequent accesses. But, the proposed algorithm is focused on the justifiable operation even in the circumstance of fast and frequent accesses.

• Korean Journal of Biological Psychiatry
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• v.23 no.4
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• pp.199-204
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• 2016

Objectives Although forgetfulness is a common complaint among menopausal depressed women, there is still a debate about the relationship between memory impairment and menopause. The aim of this study is to examine whether menopause is related to cognitive decline among women with depressive disorders. We hypothesized that postmenopausal depressed women show generally poorer performance than premenopausal depressed women on various cognitive function tests. Methods With a retrospective chart review, we identified a total of 87 female patients (45 premenopausal patients and 42 postmenopausal patients) who were hospitalized with depressive disorders from 2000 to 2016. Demographic and clinical variables and cognitive test results were compared between two groups. Results Education year is longer in premenopausal group than postmenopausal group whereas clinical characteristics (illness duration, recurrence, and symptom severity) and mean Intelligence Quotient (IQ) were similar between two groups. The postmenopausal group took longer time for Bender-Gestalt Test (BGT) recall, Trail Making Test (TMT)-A, and TMT-B than the premenopausal group. After controlling for age and education, significant difference was remained for BGT recall (p = 0.029). Conclusions Postmenopausal state may be related with decline of visuospatial memory function, in particular, among depressed female patients. Other areas of cognitive function including complex attention, verbal memory, auditory memory, and working memory might be interpreted while considering age and education level.