• 한국멀티미디어학회논문지
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• 제4권2호
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• pp.182-188
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• 2001

본 논문에서는 동역학계를 해석하는 방법들 중의 한가지인 다차원 셀룰라 오토마타에 기초한 난수열 발생 시스템을 제안하였다. 제안된 난수열 발생 시스템은 키의 사용이 요구되는 경우와 요구되지 않는 경우에 모두 적용이 가능하도록 구성되었으며, 키를 사용하는 경우 키의 크기는 128bits에서 256bits까지 가변적으로 사용할 수 있게 구성되었다. 제안된 난수열 발생 시스템의 수행속도는 Pentium MMX 200MHz (64M RAM, Windows 98) 환경에서 약 280Mbits/sec로 측정되었다.

• IEIE Transactions on Smart Processing and Computing
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• 제2권4호
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• pp.226-239
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• 2013

A number of systems have several on-chip memories with cache memory being one of them. Conventional cache memory consists of SRAM but the ratio of static energy to the total energy of the memory architecture becomes larger as the leakage power of traditional SRAM increases. Spin-Torque Transfer RAM (STT-RAM), which is a variety of Non-Volatile Memory (NVM), has many advantages over SRAM, such as high density, low leakage power, and non-volatility, but it consumes too much writing energy. This study evaluated a wide range of energy consumptions of a two-level cache using NVM partially on a mobile processor. Through a number of experimental evaluations, it was confirmed that the use of NVM partially in the two-level cache effectively reduces energy consumption significantly.

• 대한전자공학회논문지SD
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• 제44권8호
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• pp.60-64
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• 2007

본 논문에서는 유럽형 DTV용 FFT를 설계하고 Stratix EP1S25F672C6 FPGA를 이용하여 구현하였다. SIC 구조를 사용하여 FFT를 구현하였으며, 사용된 SIC 구조는 특정 알고리즘 처리 연산을 수행하기 위한 처리기와 RAM 메모리, 레지스터들과 전체 블록 및 부분 블록의 동작을 통제하기 위한 조정기로 구성된다. 디자인된 FFT는 DVB-T 표준사양을 만족하도록 2K/8K FFT 연산을 처리 가능하며, 선택적으로 1/4, 1/8, 1/16, 1/32의 4가지 보호구간 모드를 모두 지원한다. 구현된 FFT는 사용된 Stratix FPGA에 전체 로직의 12%, 전체 메모리의 53%를 사용한다.

• 한국재료학회지
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• 제32권9호
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• pp.384-390
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• 2022

A spin coating process for RRAM, which is a TiN/TiO₂/FTO structure based on a PTC sol solution, was developed in this laboratory, a method which enables low-temperature and eco-friendly manufacturing. The RRAM corresponds to an OxRAM that operates through the formation and extinction of conductive filaments. Heat treatment was selected as a method of controlling oxygen vacancy (V_O), a major factor of the conductive filament. It was carried out at 100 ℃ under moisture removal conditions and at 300 ℃ and 500 ℃ for excellent phase stability. XRD analysis confirmed the anatase phase in the thin film increased as the heat treatment increased, and the Ti³⁺ and OH- groups were observed to decrease in the XPS analysis. In the I-V analysis, the device at 100 ℃ showed a low primary SET voltage of 5.1 V and a high ON/OFF ratio of 10⁴. The double-logarithmic plot of the I-V curve confirmed the device at 100 ℃ required a low operating voltage. As a result, the 100 ℃ heat treatment conditions were suitable for the low voltage driving and high ON/OFF ratio of TiN/TiO₂/FTO RRAM devices and these results suggest that the operating voltage and ON/OFF ratio required for OxRAM devices used in various fields under specific heat treatment conditions can be compromised.

• 대한기계학회논문집A
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• 제34권4호
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• pp.383-390
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• 2010

본 논문에서는 알루미늄 분말의 치밀화 거동을 분석하기 위하여 다입자유한요소모델을 이용한 분말압축 해석방법을 제시하였다. 다입자유한요소모델을 이용하여 압축공정 동안 압축속도와 입자크기가 입자의 변형거동과 분말의 치밀화에 미치는 영향을 조사하였다. 유한요소해석결과는 평균입도 20, $3{\mu}m$의 알루미늄 분말에 대한 일축압축시험을 통해 검증되었다. 압축시험은 만능재료시험기(MTS)를 이용하였으며 해석과 동일하게 5와 15, 30, 60mm/min 압축속도에 대해 수행되었다. 입자직경이 감소할수록 입자간 마찰이 증가하기 때문에 압출하중은 증가하였다. 압축속도가 감소할수록 증가된 입자의 회전모멘트는 입자간의 이동과 분말의 치밀화에 기여하여 최종 분말의 상대밀도를 증가시킨다.

• Applied Microscopy
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• 제42권4호
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• pp.207-211
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• 2012

We examined the electrical properties and microstructure of NiO produced using a sol-gel method and Ni nitrate hexahydrate ($Ni[NO_3]_2{\cdot}6H_2O$) to investigate if this NiO thin film can be used as an insulator layer for resistance random access memory (ReRAM) devices. It was found that as-prepared NiO film was polycrystalline and presented as the nonstoichiometric compound $Ni_{1+x}O$ with Ni interstitials (oxygen vacancies). Resistances-witching behavior was observed in the range of 0~2 V, and the low-resistance state and high-resistance state were clearly distinguishable (${\sim}10^3$ orders). It was also demonstrated that NiO could be patterned directly by KrF eximer laser irradiation using a shadow mask. NiO thin film fabricated by the sol-gel method does not require any photoresist or vacuum processes, and therefore has potential for application as an insulating layer in low-cost ReRAM devices.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8413-8422
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• 2014

Background: To investigate the relationship of five TP53 polymorphisms (p.P47S, p.R72P, PIN3 ins16bp, p.R213R and r.13494g>a) with the esophageal cancer (EC) risk in North Indians. Materials and Methods: Genotyping of p.P47S, p.R72P, PIN3 ins16bp, p.R213R and r.13494g>a polymorphisms of TP53 in 136 sporadic EC patients and 136 controls using polymerase chain reaction and PCR-RFLP. Results: The frequencies of genotype RR, RP and PP of p.R72P polymorphism were 16.91 vs 26.47%, 58.82 vs 49.27% and 24.27 vs 24.27% among patients and controls respectively. We observed significantly increased frequency of RP genotype in cases as compared to controls (OR=1.87, 95% CI, 1.01-3.46, p=0.05). The frequencies of genotype A1A1, A1A2 and A2A2 of PIN3 ins16bp polymorphism were 69.12 vs 70.59%, 27.20 vs 25% and 3.68 vs 4.41% among patients and controls. There was no significant difference among genotype and allele distribution between patients and controls. The frequencies of genotype GG, GA and AA of r.13494g>a polymorphism were 62.50 vs 64.70%, 34.56 vs 30.15% and 2.94 vs 5.15% among patients and controls respectively. No significant difference between genotype and allele frequency was observed in the patients and controls. For p.P47S and p.R213R polymorphisms, all the cases and controls had homozygous wild type genotype. The RP-A1A1-GG genotype combination shows significant risk for EC (OR=2.01, 95%CI: 1.01-3.99, p=0.05). Conclusions: Among the five TP53 polymorphisms investigated, only p.R72P polymorphism may contributes to EC susceptibility.

• The Korean Journal of Pain
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• 제27권4호
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• pp.353-359
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• 2014

Background: Epidural steroid injections are an accepted procedure for the conservative management of chronic backache caused by lumbar disc pathology. The purpose of this study was to evaluate the epidurographic findings for the midline, transforaminal and parasagittal approaches in lumbar epidural steroid injections, and correlating them with the clinical improvement. Methods: Sixty chronic lower back pain patients with unilateral radiculitis from a herniated/degenerated disc were enrolled. After screening the patients according to the exclusion criteria and randomly allocating them to 3 groups of 20 patients, fluoroscopic contrast enhanced epidural steroids were injected via midline (group 1), transforaminal (group 2) and parasagittal interlaminar (group 3) approaches at the level of the pathology. The fluoroscopic patterns of the three groups were studied and correlated with the clinical improvement measured by the VAS over the next 3 months; any incidences of complications were recorded. Results: The transforaminal group presented better results in terms of VAS reduction than the midline and parasagittal approach groups (P < 0.05). The epidurography showed a better ventral spread for both the transforaminal (P < 0.001) and the paramedian approaches (P < 0.05), as compared to the midline approach. The nerve root filling was greater in the transforaminal group (P < 0.001) than in the other two groups. The ventral spread of the contrast agent was associated with improvement in the VAS score and this difference was statistically significant in group 1 (P < 0.05), and highly significant in groups 2 and 3 (P < 0.001). In all the groups, any complications observed were transient and minor. Conclusions: The midline and paramedian approaches are technically easier and statistically comparable, but clinically less efficacious than the transforaminal approach. The incidence of ventral spread and nerve root delineation show a definite correlation with clinical improvement. However, an longer follow-up period is advisable for a better evaluation of the actual outcom.

• 한국재료학회지
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• 제20권5호
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• pp.241-245
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• 2010

One of the weak points of the Cr-doped SZO is that until now, it has only been fabricated on perovskite substrates, whereas NiO-ReRAM devices have already been deposited on Si substrates. The fabrication of RAM devices on Si substrates is important for commercialization because conventional electronics are based mainly on silicon materials. Cr-doped ReRAM will find a wide range of applications in embedded systems or conventional memory device manufacturing processes if it can be fabricated on Si substrates. For application of the commercial memory device, Cr-doped $SrZrO_3$ perovskite thin films were deposited on a $SrRuO_3$ bottom electrode/Si(100)substrate using pulsed laser deposition. XRD peaks corresponding to the (112), (004) and (132) planes of both the SZO and SRO were observed with the highest intensity along the (112) direction. The positions of the SZO grains matched those of the SRO grains. A well-controlled interface between the $SrZrO_3$:Cr perovskite and the $SrRuO_3$ bottom electrode were fabricated, so that good resistive switching behavior was observed with an on/off ratio higher than $10^2$. A pulse test showed the switching behavior of the Pt/$SrZrO_3:Cr/SrRuO^3$ device under a pulse of 10 kHz for $10^4$ cycles. The resistive switching memory devices made of the Cr-doped $SrZrO_3$ thin films deposited on Si substrates are expected to be more compatible with conventional Si-based electronics.

• Asian Pacific Journal of Cancer Prevention
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• 제16권16호
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• pp.7077-7084
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• 2015

Background: Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy among males in India. While tobacco and alcohol are main aetiological factors, human papilloma virus (HPV) presence has surprisingly increased in head and neck Squamous Cell Carcinoma (HNSCC) in the past two decade but its frequency in OSCCS is still uncertain. We aim to explore the frequency of HPV and its major genotypes in North Indian patients and their association with clinicopathological and histopathological features and p16 expression pattern. Materials and Methods: The study group comprised 250 histologically proven cases of OSCC. HPV was detected by real time PCR in tumor biopsy specimens and confirmed by conventional PCR with PGMY09/PGMY11 primers. Genotyping for high-risk types 16/18 was conducted by type specific PCR. p16 expression was assessed by immunohistochemsitry. Results: HPV presence was confirmed in 23/250 (9.2%) OSCC cases, of which 30.4% had HPV 16 infection, 17.4%were positive for HPV 18 and 26.1% had co-infections. HPV presence was significantly associated with male gender (p=0.02) and habit of pan masala chewing (p=0.01). HPV positive cases also had a history of tobacco consumption in 91.3% cases. p16 over expression was observed in 39.1% of HPV positive cases but this was not significantly different from negative cases (p=0.54). Conclusions: The frequency of HPV in OSCC is low in North-India and majority of cases are associated with a tobacco habit. It appears that tobacco shows a confounding effect in HPV positive cases and use of p16 protein as a reliable marker to assess the potential etiological role of HPV in OSCC in our population is not suggested.