• Korean Chemical Engineering Research
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• 제57권3호
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• pp.425-431
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• 2019

As rechargeable metal-air batteries will be ideal energy storage devices in the future, an active cathode electrocatalyst is required with bi-functionality on both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) during discharge and charge, respectively. Here, a class of perovskite cathode catalyst with a micro-tubular structure has been developed by controlling bi-functionality from different Ru and Ni dopant ratios. A micro-tubular structure is achieved by the activated carbon fiber (ACF) templating method, which provides uniform size and shape. At the perovskite formula of $LaCrO_3$, the dual dopant system is successfully synthesized with a perfect incorporation into the single perovskite structure. The chemical oxidation states for each Ni and Ru also confirm the partial substitution to B-site of Cr without any changes in the major perovskite structure. From the electrochemical measurements, the micro-tubular feature reveals much more efficient catalytic activity on ORR and OER, comparing to the grain catalyst with same perovskite composition. By changing the Ru and Ni ratio, the $LaCr_{0.8}Ru_{0.1}Ni_{0.1}O_3$ micro-tubular catalyst exhibits great bi-functionality, especially on ORR, with low metal loading, which is comparable to the commercial catalyst of Pt and Ir. This advanced catalytic property on the micro-tubular structure and Ru/Ni synergy effect at the perovskite material may provide a new direction for the next-generation cathode catalyst in metal-air battery system.

• Current Optics and Photonics
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• 제2권2호
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• pp.147-152
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• 2018

We propose a novel bi-focal metallic Fresnel zone plate (MFZP) with shallow depth-of-field (DOF) characteristics. We design the specific annular slit patterns, exploiting the phase-selection-rule method along with the particle swarm optimization algorithm, which we have recently proposed. We numerically investigate the novel characteristics of the bi-focal MFZP in comparison with those of another bi-focal MFZP having equivalent functionality but designed by the conventional multi-zone method. We verify that whilst both bi-focal MFZPs can produce dual focal spots at $15{\mu}m$ and $25{\mu}m$ away from the MFZP plane, the former exhibits characteristics superior to those of the latter from the viewpoint of axial resolution, including the axial side lobe suppression and axial DOF shallowness. We expect the proposed bi-focal MFZP can readily be fabricated with electron-beam evaporation and focused-ion-beam processes and further be exploited for various applications, such as laser micro-machining, optical trapping, biochemical sensing, confocal sensing, etc.

• 한국정보시스템학회지:정보시스템연구
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• 제31권4호
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• pp.101-121
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• 2022

Purpose This study aims to introduce a Smart-Platform for solving numerous problems in urban cities and improving citizens' convenience. This Smart-Platform is achieved by studying the City Data Hub technology to build and spread a Smart City Data Hub . Design/methodology/approach In this study, we analyzed the functions in detail and interlocking flows specific to the published City Data Hub module and designed a Smart-Platform with additional UI-based functions to improve users' convenience based on our previous experience. Findings The City Data Hub will provide a modular data hub platform functionality for application by different stakeholders. However, further research on detailed functionality and experience in interworking legacy systems will be required to apply the platform realistically. Therefore, we judged that this Smart-Platform, which supplements the City Data Hub with additional functions, would be useful for utilizing the City Data Hub in the future. Through the demonstration of the platform designed, it is also necessary to explore the direction of continuous development for the future.

• JSTS:Journal of Semiconductor Technology and Science
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• 제4권3호
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• pp.196-203
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• 2004

A three-dimensional (3D) IC technology platform is presented for high-performance, low-cost heterogeneous integration of silicon ICs. The platform uses dielectric adhesive bonding of fully-processed wafer-to-wafer aligned ICs, followed by a three-step thinning process and copper damascene patterning to form inter-wafer interconnects. Daisy-chain inter-wafer via test structures and compatibility of the process steps with 130 nm CMOS sal devices and circuits indicate the viability of the process flow. Such 3D integration with through-die vias enables high functionality in intelligent wireless terminals, as vertical integration of processor, large memory, image sensors and RF/microwave transceivers can be achieved with silicon-based ICs (Si CMOS and/or SiGe BiCMOS). Two examples of such capability are highlighted: memory-intensive Si CMOS digital processors with large L2 caches and SiGe BiCMOS pipelined A/D converters. A comparison of wafer-level 3D integration 'lith system-on-a-chip (SoC) and system-in-a-package (SiP) implementations is presented.

• Macromolecular Research
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• 제15권6호
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• pp.541-546
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• 2007

The combination of atom transfer radical polymerization (ATRP) and click chemistry was employed for the efficient preparation of well-defined block copolymers. Bromo terminated poly(methyl acrylate) (pMA-Br) was prepared by an ATRP initiator, ethyl-2-bromoisobutyrate (EBiB). Subsequently, the bromine chain end of pMA-Br was converted to an azide group by simple nucleophilic substitution reaction. ${\alpha}-Alkyn-{\omega}-bromo-functionalized$ polystyrene was also synthesized by ATRP using the alkyn-functionalized initiator, propargyl-2-bromoisobutyrate (PgBiB). In both cases, the conversion was limited to a low level to ensure a high degree of chain end functionality. Then the coupling reaction between the azide end group in $pMA-N_3$ and alkyn-functionalized PgBiB-pSt was performed by Cu(I)catalysis. This coupling reaction was monitored by gel permeation chromatography (GPC). The synthesized block copolymer was characterized by FT-IR, $^1H-NMR$ spectroscopy and $^1H-^1H$ COSY correlation spectroscopy.

• 복식문화연구
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• 제21권2호
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• pp.246-260
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• 2013

This research was carried out on women in their 20s and 30s who have overweight lower body. The subjects selected for this study were women a Rohrer index of 1.6 or higher, a waist circumference 78.5cm to 83.5cm, and a lower drop of at least 18cm. The aim is to propose a prototype of bi-stretch pants meeting demands for both functionality and aesthetic appeal. Various clothing patterns ease amount of the waist and hip circumferences and crotch depths and were developed. They had different crotch widths, and center back line angles. The results showed that the best pants patterns were ease 1cm to the total hip circumference. The front hip circumference was H/4-0.5cm, and the back hip circumference was H/4+1cm. The front crotch width was H/20+1cm, the back crotch width was H/10+3cm. No additional ease was given to the total waistline. The front waist circumference was W/4+0.5cm. The back waist circumference was W/4-0.5cm. The knee circumference was set at 44cm, the pant hem width was set at 36cm, and the pant length was set at 100cm-5cm. The findings of this research can be used as basic data for stretch pants that fit the abdomen, hips, and thighs for women in their 20s and 30s with overweight lower body.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제11권5호
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• pp.416-426
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• 2005

기업간통합(business-to-business integration; B2Bi) 시스템은 XML 메시지의 송수신 내역을 고속으로 기록하고 검색할 수 있는 메시지 저장시스템이 필요하다 XML 전용데이타베이스 시스템 또는 XML 데이타타입을 지원하는 관계형데이타베이스는 도입 비용과 기능의 과도함 때문에 메시지 저장시스템으로는 적합하지 않다. XML 데이타를 관계형데이타베이스의 레코드로 분산시켜 저장하는 저장 방식 또한 수행 성능이 떨어지거나 구현이 복잡하므로 사용하기 어렵다. 이에 본 논문은 관계형데이타베이스를 사용하여 메시지 저장시스템을 구현하기 위한 단순한 구조의 메시지 저장 방식을 제안한다. 제안하는 저장방식은 메시지 타입별로 색인필드를 등록하고 색인필드를 통해서만 메시지를 검색한다. 따라서 XQL과 같은 강력한 검색 기능은 지원하지 못하나 비교적 단순한 저장 구조만으로도 고속의 메시지 기록과 제한된 형태의 메시지 검색이 가능하다 제안하는 저장방식을 구현하기 위해서는 세 가지의 데이타베이스 스키마를 사용할 수 있으며 실험 평가를 통해 이들 세 가지의 스키마가 가지는 성능상의 장단점을 평가한다.

• IMMUNE NETWORK
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• 제14권2호
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• pp.67-72
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• 2014

The herpes virus entry mediator (HVEM) is a member of the tumor necrosis factor receptor superfamily (TNFRSF), and therefore it is also known as TNFRSF14 or CD270 (1,2). In recent years, we have focused on understanding HVEM function in the mucosa of the intestine, particularly on the role of HVEM in colitis pathogenesis, host defense and regulation of the microbiota (2-4). HVEM is an unusual TNF receptor because of its high expression levels in the gut epithelium, its capacity to bind ligands that are not members of the TNF super family, including immunoglobulin (Ig) superfamily members BTLA and CD160, and its bi-directional functionality, acting as a signaling receptor or as a ligand for the receptor BTLA. Clinically, Hvem recently was reported as an inflammatory bowel disease (IBD) risk gene as a result of genome wide association studies (5,6). This suggests HVEM could have a regulatory role influencing the regulation of epithelial barrier, host defense and the microbiota. Consistent with this, using mouse models, we have revealed how HVEM is involved in colitis pathogenesis, mucosal host defense and epithelial immunity (3,7). Although further studies are needed, our results provide the fundamental basis for understanding why Hvem is an IBD risk gene, and they confirm that HVEM is a mucosal gatekeeper with multiple regulatory functions in the mucosa.

• 한국자원식물학회지
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• 제24권3호
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• pp.330-336
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• 2011

The recent disaster of earthquake and tsunami on March 11, 2011 severely attacked East Japanese cities and people, and in addition, the accident of nuclear power station will inevitably damage the agricultural activities there. The economical depression influences on the horticulture and floriculture industry as well, through the reluctant consumption all over the country. Such a situation reflects a conventional perception that the garden plants or ornamental plants have been regarded as a symbol of capitalism, representing the success, luxury, beauty or other metaphors indicating the winners of business war. But as the word "culture" means "cultivation" originally, horti "culture" or flori "culture" should have played some roles in cultivating lands as well as cultivation of human minds, leading to develop a modern "culture" which may lay emphases on personality, originality, partnership, cooperation, diversity and so forth. In this article, a brief history of garden plants in Japan, as well as some current movements in Japanese horticulture and floriculture, is reviewed with some commodities which possess messages on creating a new humane culture.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.201-202
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• 2012

This paper presents a simple and cost-effective stand-alone rapid battery charging system of 30kW for electric vehicles. The proposed system mainly consists of active front-end rectifier of neutral point clamped 3-level type and non-isolated bi-directional dc-dc converter of multi-phase interleaved half-bridge topology. The charging system is designed to operate for both lithium-polymer and lithium-ion batteries. The complete charging sequence is made up of three sub-interval operating modes; pre-charging mode, constant-current mode, and constant-voltage mode. Each mode is operated according to battery states: voltage, current and State of Charging (SOC). The proposed system is able to reach the full-charge state within less than 16min for the battery capacity of 8kWh by supplying the charging current of 67A. The optimal discharging algorithm for Vehicle to the Grid (V2G) operation has been adopted to maintain the discharging current of 1C. Owing to the simple and compact power conversion scheme, the proposed solution has superior module-friendly mechanical structure which is absolutely required to realize flexible power expansion capability in a very high-current rapid charging system. Experiment waveforms confirm the proposed functionality of the charging system.