• ETRI Journal
• /
• v.32 no.4
• /
• pp.626-629
• /
• 2010

In this letter, we present an enhanced block-based adaptive loop filter (E-BALF) with multiple filter symmetric structures. The E-BALF adapts various filter symmetric structures in a rate-distortion optimization sense, reflecting the statistical properties of each image in a video sequence. Experimental results show that the proposed method achieves a reduction in the Bj${\phi}$ntegaard delta (BD)-bitrate by an average of 9.60% compared with Joint Model 11.0 of H.264/AVC. Compared to the state-of-the-art BALF, a reduction of up to 1.13% in BD-bitrate is achieved.

• ETRI Journal
• /
• v.43 no.5
• /
• pp.891-899
• /
• 2021

We propose a stray inductance extraction method on power modules of the few-kilovolts/several-hundred-amperes class using only low voltages and low currents. The method incorporates a double-pulse generator, a level shifter, a switching device, and a load inductor. The conventional approach generally requires a high voltage of more than half the power module's rated voltage and a high current of around half the rated current. In contrast, the proposed method requires a low voltage and low current environment regardless of the power module's rated voltage because the module is measured in a turn-off state. Both theoretical and experimental results are provided. A physical circuit board was fabricated, and the method was applied to three commercial power modules with EconoDUAL3 cases. The obtained stray inductance values differed from the manufacturer-provided values by less than 1.65 nH, thus demonstrating the method's accuracy. The greatest advantage of the proposed approach is that high voltages or high currents are not required.

• Journal of Korea Technology Innovation Society
• /
• v.18 no.4
• /
• pp.693-718
• /
• 2015

This paper examines the presence of network structures among convergence technologies focusing on national R&D projects performed by GRIs(Government-sponsored Research Institutes) in Korea. The dataset of convergence technology projects, which were conducted by 24 GRIs over 3 years (2011-2013), are analysed using the network analysis method. In this paper, a convergence technology project is defined as a project that consists of 2 or more then 2 technologies according to the intermediate classification of National Standard Classification of S&T. The research results confirm that convergence researches of government-sponsored research institutes are performed more actively than the entire convergence researches of national R&D projects. Furthermore, technological fields of GRIs' convergence projects are found to be much more varied. This paper also shows that in-house researches are more active than collaborative ones with external organizations. According to the network centrality analysis, it is identified that the network central characteristics of convergence technologies can be classified into internally oriented technologies and externally oriented technologies. Convergence technologies do not just mean simple mixture of different technologies. Therefore Korean government-sponsored research institutes should make more efforts to create convergence research areas which could generate new technologies and industries more effectively than simple multidisciplinary technology researches. From this perspective, some policy suggestions can be derived on the role of government-sponsored research institutes for activating convergence researches through the analysis of status of convergence researches and networks of institutions.

• ETRI Journal
• /
• v.39 no.4
• /
• pp.467-479
• /
• 2017

This study examines how the characteristics of cooperative research and development (R&D) projects in the public domain impact information and communication technology (ICT) convergence. Based on the analysis of 416 cooperative R&D projects under the ICT-based industry convergence R&D program in Korea, the study finds that the characteristics of cooperative R&D projects significantly impact ICT convergence. Moreover, the participation of public research institutes and universities is critical for ICT convergence compared with that of firms. However, in firm-to-firm cooperation, the participation of small and medium enterprises contributes to cross-sectional convergence, while the participation of large firms leads to overall and longitudinal convergence. R&D inputs such as the number of partners and government subsidies exhibit an inverted U-shaped relationship (negative quadratic effect) with technology convergence. Project duration and homogeneous partners are also critical factors for ICT convergence. The results indicate several implications and guidelines on how to effectively organize cooperative R&D projects to facilitate technology convergence.

• ETRI Journal
• /
• v.45 no.3
• /
• pp.543-550
• /
• 2023

Electrostatic discharge (ESD) testing for human body model tests is an essential part of the reliability evaluation of electronic/electrical devices and components. However, global environmental concerns have called for the need to replace the mercury-wetted relay switches, which have been used in ESD testers. Therefore, herein, we propose an ESD tester using metal oxide semiconductor-controlled thyristor (MCT) devices with a significantly higher rising rate of anode current (di/dt) characteristics. These MCTs, which have a breakdown voltage beyond 3000 V, were developed through an in-house foundry. As a replacement for the existing mercury relays, the proposed ESD tester with the developed MCT satisfies all the requirements stipulated in the JS-001 standard for conditions at or below 2000 V. Moreover, unlike traditional relays, the proposed ESD tester does not generate resonance; therefore, no additional circuitry is required for resonant removal. To the best of our knowledge, the proposed ESD tester is the first study to meet the JS-001 specification by applying a new switch instead of an existing mercury-wetted relay.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.35 no.3
• /
• pp.292-296
• /
• 2022

(La_0.5Nd_0.2Sr_0.3)MnO₃ specimens were prepared by a solid-state reaction. In all specimens, X-ray diffraction patterns of an orthorhombic structure were shown. The fracture surfaces of (La_0.5Nd_0.2Sr_0.3)MnO₃ specimens showed a transgranular fracture pattern be possibly due to La ions (0.122 nm) as a perovskite A-site dopant substituting for Nd ions (0.115 nm) having a small ionic radius. The full-width at half maximum (FWHM) of the Mn 2p XPS spectra showed a value greater than that [8] of the single valence state, which is believed to be due to the overlapping of Mn²⁺, Mn³⁺, and Mn⁴⁺ ions. The dependence of Mn 2p spectra on the Mn³⁺/Mn⁴⁺ ratio according to sintering time was not observed. Electrical resistivity resulted in the minimum value of 100.7 Ω-cm for the specimen sintered for 9 hours. All specimens show a typical negative temperature coefficient of resistance (NTCR) characteristics. In the 9-hour sintered specimen, TCR, activation energy, and B25/65-value were -1.24%/℃, 0.19 eV, and 2,445 K, respectively.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.10a
• /
• pp.1390-1392
• /
• 2015

최근 다양한 웨어러블 기기의 등장으로 인해, 이종의 라이프로그 정보로부터 개인별 맞춤형 건강관리 서비스를 제공할 수 있는 분석 솔루션의 중요성이 대두되고 있다. 본 연구에서는 이기종의 웨어러블 기기를 통해 수집된 라이프로그 정보를 근간으로 개인의 건강상태를 모니터링하고 분석할 수 있는 웰니스 인포메틱스엔진에 대한 프레임워크를 소개한다. 또한 개발된 인포메틱스엔진의 효과성은 실증시범서비스 기간 동안에 수집된 다양한 라이프로그 정보를 활용하여, 2가지 벤치마크 방법들과의 예측능력을 비교함으로써 그 효과성을 제시한다.

• Molecules and Cells
• /
• v.47 no.3
• /
• pp.100009.1-100009.3
• /
• 2024

• Molecules and Cells
• /
• v.46 no.12
• /
• pp.743-745
• /
• 2023

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.22 no.3
• /
• pp.414-420
• /
• 2013

Research on decreasing the weight of composite sandwich panels is in progress. This paper reports the experimental results for the mechanical behavior of a composite sandwich panel. The skins of sandwich panels were made of glass fiber sheets and plywood matrix composites. Their interior layers consisted of glass fiber pultrusion pipes and gold foam. Experimental tests were performed to obtain the mechanical properties and complex mechanical behavior. Before fatigue tests, tensile tests and 3-point bending tests were carried out to obtain the optimal design and determine their strength and failure mechanisms in the flat-wise position. After the static test, a fatigue test were conducted at a load frequency of 5 Hz, stress ratio (R) of 0.1, and endurance limit for the S-N curve. It showed that the failure modes were related to both the core design and skin failure.