• 한국정보통신학회논문지
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• 제25권12호
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• pp.1914-1919
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• 2021

첨단산업의 발전에 따라 영상처리 하드웨어의 연구는 필수적이고, 실제 칩 동작을 위해서는 게이트 수준의 타이밍 검증이 필요하다. 이를 위해 주로 FPGA 기반 검증이 이루어지는데 기존에는 DDR3 메모리 인터페이스를 적용했지만, 최근에는 FPGA 스펙이 향상되면서 DDR4 메모리가 사용된다. 이 때 기존에 사용하던 메모리 인터페이스를 적용하면 CPU와 메모리의 성능 차이에 의한 신호들의 타이밍 불일치가 발생하기 때문에 사용할 수 없다. 본 논문에서는 기존 인터페이스 시스템 FSM의 State 최적화를 통해 문제를 해결하고, 이 과정에서 AXI Data Width 수정을 통해 데이터 읽기 속도를 2배 증가시킨다. 실제 사례 분석을 위해 Xilinx 사의 SoC보드 중 DDR3 메모리를 사용하는 ZC706과 DDR4 메모리를 사용하는 ZCU106을 사용한다.

• 한국방사선학회논문지
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• 제1권1호
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• pp.25-30
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• 2007

본 연구의 목적은 ROC를 이용하여 일반 촬영기기에 따른 영상의 질을 평가해보고자 함이다. 본 연구의 수행을 위하여 CR(Computed Radiography)과 DDR(Direct Digital Radiography)을 사용하였으며 피사체로 흉부 팬텀을 사용하였다. 각 기기에서 영상을 획득한 후 ROC평가를 이용하여 영상의 질 및 기기의 특성을 평가하였다. 조사 조건으로 관전압 120kVp와 관전류량 3.2 mAs를 이용하였고 SID(Source to Image Distance)는 180cm로 설정하였다. 팬텀의 심장, 폐야, 흉추부위에 병소를 표현하였으며 각 장비에서 획득한 영상의 질 및 기기의 특성을 파악하기 위하여 방사선학 전공자 29명을 대상으로 ROC평가를 실시하였다. ROC 평가 결과 DDR의 TPF(true positive fraction)는 0.552, FPF(false positive fraction)는 0.474, CR의 TPF는 0.629, FPF는 0.405로 나타났다. 본 연구 결과 CR의 영상이 DDR의 영상보다 더 나은 영상의 질을 나타내는 것을 확인하였다. 영상의 질의 확연한 차이의 원인은 DDR의 경우 enhance board의 미 삽입으로 인한 영상 후처리의 미수행이라고 사료된다. 추후 DDR의 enhance board의 삽입 후 영상의 후처리가 가미된 DDR영상의 질에 대한 연구가 필요하며 본 연구의 결과로 인하여 영상의 후처리가 임상의 판독에 있어서 매우 중요한 요소임을 확인할 수 있었다.

• Molecules and Cells
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• 제41권2호
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• pp.93-102
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• 2018

Discoidin domain receptor 1 (DDR1) is involved in tumorigenesis and angiogenesis. However, its role in lymphangiogenesis has been unknown. Here, we tested whether downregulation of DDR1 expression by miR-199a/b can suppress lymphangiogenesis. We also aimed to identify miRNA target site(s) in the 3' untranslated region (UTR) of DDR1. Transfection with miR-199a/b-5p mimics reduced expression of DDR1 and tube formation in primary human dermal lymphatic endothelial cells, whereas miR-199a/b-5p inhibitors showed the opposite effects. Critically, injection of miR-199a/b-5p mimics suppressed DDR1 expression and lymphangiogenesis in a corneal alkali-burn rat model. The three well-conserved seed matched sites for miR-199a/b-5p in the DDR1 3'-UTR were targeted, and miRNA binding to at least two sites was required for DDR1 inhibition. Our data suggest that DDR1 promotes enhanced lymphangiogenesis during eye injury, and miR-199a/b-5p suppresses this activity by inhibiting DDR1 expression. Thus, this miRNA may be useful for the treatment of lymphangiogenesis-related eye diseases.

• Journal of information and communication convergence engineering
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• 제7권2호
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• pp.203-208
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• 2009

Recently, improved capabilities of the mobile device is represented in a demand for same level services with the desktop device services but the service that is developed for desktop device is not compatible with mobile devices. To fulfill these demands, it is needed to provide services with considering features of mobile devices. This means that CP(Contents Provider) must do contents transformation in order to make suitable contents on mobile device. For managing some information that is required to do contents transformation, we need the DDR(Device Description Repository) which can store and search a variety of device information to grasp the constraints on the mobile device as compared with desktop devices. Also, defining standard API is required to offer a service regardless of platforms. Hereupon W3C(World Wide Web Consortium) introduced DDR Simple API. However that specifies the limited functions of DDR, which is inevitable to be added for more precise search services. In this paper, we expanded DDR Simple API and implemented DDR that supports DDL(Device Description Language) conversion and storing and searching device information.

• 방사선산업학회지
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• 제4권3호
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• pp.289-295
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• 2010

The bacterium Deinococcus radiodurans is one of the most resistant organisms to the effects of ionizing radiation and other DNA-damaging agents. In this study, distributions of 10 ddr (DNA damage response) genes were investigated in 8 species of Deinococcus by polymerase chain reaction (PCR). We have compared the sequences of ddr genes of D. radiodurans, D. geothermalis and D. deserti, and selected primers which are suitable for the detection of ddr in different species of Deinococcus. A sequence homology search and PCR assay showed that ddrO, which encodes a global regulator of the radiation-desiccation response, was most well conserved in the Deinococcus lineage.

• 전기전자학회논문지
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• 제21권4호
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• pp.416-419
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• 2017

본 논문에서는 고속 DDR3/DDR4 SDRAM을 위한 새로운 디지털 지연고정루프 (delay-locked loop: DLL)를 제안한다. 제안하는 디지털 DLL은 디지털 지연라인의 boundary switching 문제에 의한 jitter 증가 문제를 제거하기 위하여 위상보간 (phase interpolation) 방식의 파인지연라인 (fine delay line)을 채택하였다. 또한, 제안하는 디지털 DLL은 harmonic lock 문제를 제거하기 위하여 새로운 점진직 검색 (gradual search) 알고리즘을 사용한다. 제안하는 디지털 DLL은 1.1V, 38-nm CMOS DRAM 공정으로 설계되었으며, 0.25-2.0 GHz의 주파수 동작 영역을 가진다. 2.0 GHz에서 1.1 ps의 피크-투-피크 (p-p) 지터를 가지며, 약 13 mW의 전력소모를 가진다.

• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.427-438
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• 2022

Pyroptosis, a form of cell death associated with inflammation, is known to be involved in diabetic nephropathy (DN), and discoid domain receptor 1 (DDR1), an inflammatory regulatory protein, is reported to be associated with diabetes. However, the mechanism underlying DDR1 regulation and pyroptosis in DN remains unknown. We aimed to investigate the effect of DDR1 on renal tubular epithelial cell pyroptosis and the mechanism underlying DN. In this study, we used high glucose (HG)-treated HK-2 cells and rats with a single intraperitoneal injection of streptozotocin as DN models. Subsequently, the expression of pyroptosis-related proteins (cleaved caspase-1, GSDMD-N, Interleukin-1β [IL-1β], and interleukin-18 [IL-18]), DDR1, phosphorylated NF-κB (p-NF-κB), and NLR family pyrin domain-containing 3 (NLRP3) inflammasomes were determined through Western blotting. IL-1β and IL-18 levels were determined using ELISA. The rate of pyroptosis was assessed by propidium iodide (PI) staining. The results revealed upregulated expression of pyroptosisrelated proteins and increased concentration of IL-1β and IL-18, accompanied by DDR1, p-NF-κB, and NLRP3 upregulation in DN rat kidney tissues and HG-treated HK-2 cells. Moreover, DDR1 knockdown in the background of HG treatment resulted in inhibited expression of pyroptosis-related proteins and attenuation of IL-1β and IL-18 production and PI-positive cell frequency via the NF-κB/NLRP3 pathway in HK-2 cells. However, NLRP3 overexpression reversed the effect of DDR1 knockdown on pyroptosis. In conclusion, we demonstrated that DDR1 may be associated with pyroptosis, and DDR1 knockdown inhibited HG-induced renal tubular epithelial cell pyroptosis. The NF-κB/NLRP3 pathway is probably involved in the underlying mechanism of these findings.

• 마이크로전자및패키징학회지
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• 제19권4호
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• pp.45-50
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• 2012

A family of multi-die DRAM packages was developed that incorporate the full functionality of an SODIMM into a single package. Using a common ball assignment analogous to the edge connector of an SODIMM, a broad range of memory types and assembly structures are supported in this new package. In particular DDR3U, LPDDR3 and DDR4RS are all supported. The center-bonded DRAM use face-down wirebond assembly, while the peripherybonded LPDDR3 use the face-up configuration. Flip chip assembly as well as TSV stacked memory is also supported in this new technology. For the center-bonded devices (DDR3, DDR4 and LPDDR3 ${\times}16$ die) and for the face up wirebonded ${\times}32$ LPDDR3 devices, a simple manufacturing flow is used: all die are placed on the strip in a single machine insertion and are sourced from a single wafer. Wirebonding is also a single insertion operation: all die on a strip are wirebonded at the same time. Because the locations of the power signals is unchanged for these different types of memories, a single consolidated set of test hardware can be used for testing and burn-in for all three memory types.

• Nutrition Research and Practice
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• 제9권1호
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• pp.99-105
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• 2015

BACKGROUND/OBJECTIVES: Compelling evidence indicates that consumption of trans-fatty acids (TFA) is associated with a wide range of diseases. However, few validated tools for TFA intake assessment are available in Korea. We aimed to validate a food frequency questionnaire (FFQ) estimating usual intake of TFA in Korean adults. MATERIALS/METHODS: Eighty-two healthy adults completed an FFQ with a 3-day diet record (3DDR), and 58 completed a second FFQ at a 1-month interval. To assess the reproducibility of the FFQ, we compared estimated TFA intakes from each FFQ. To assess the validity, we compared estimates from the FFQ with those from the 3DDR. RESULTS: The FFQ was reproducible (Spearman r = 0.71) and provided modest correlations with the 3DDR (Spearman r = 0.38). After adjustment for total energy intake, the correlations increased (r = 0.45). Measurement-error correction also de-attenuated the correlations (r = 0.57). When quintiles of the FFQ and 3DDR were joint-classified, 9% on average were misclassified into extreme quintiles. CONCLUSIONS: Our findings suggest that the developed FFQ is reproducible and reasonably valid in categorizing individuals according to TFA intakes among healthy young and middle aged adults in Korea.

• 한국항행학회논문지
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• 제15권6호
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• pp.1104-1110
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• 2011

현재의 반도체 검사장비는 테스트 패턴 프로그램을 위한 메모리로 시스템 설계가 간단하고 리프레시가 필요 없는 SRAM(static random access memory) 모듈을 채용하고 있다. 그러나 SRAM 모듈을 이용한 시스템 구성은 용량이 커질수록 장비의 부피가 증가하기 때문에 메모리 대용량화 및 장비의 소형화에 걸림돌이 되고 있다. DRAM(dynamic random access memory)을 이용하여 반도체 검사 장비를 제작할 경우 SRAM 보다 비용과 장비의 면적이 줄어드는 장점이 있지만 DRAM의 특성 상 메모리 셀 리프레시가 필요하여 정시성을 보장해야 하는 문제가 있다. 따라서 본 논문에서는 이러한 문제를 해결하기 위해 DDR2 SDRAM(double data rate synchronous dynamic random access memory)을 이용한 비메모리 검사장비에서 정시성을 보장해 주는 알고리즘을 제안하고 알고리즘을 이용한 메모리 컨트롤러를 개발하였다. 그 결과, DDR2 SDRAM을 이용할 경우 SRAM을 이용할 때 보다 가격과 면적이 줄어들어 가격측면에서는 13.5배 그리고 면적측면에서는 5.3배 이득이 있음을 확인하였다.