• 한국재료학회지
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• 제27권8호
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• pp.438-444
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• 2017

In this work, the effects of hydrogen reduction on the microstructure and thermoelectric properties of $(GeTe)_{0.85}(AgSbTe_2)_{0.15}$ (TAGS-85) were studied by a combination of gas atomization and spark plasma sintering. The crystal structure and microstructure of TAGS-85 were characterized by X-ray diffraction(XRD) and scanning electron microscopy (SEM). The oxygen content of both powders and bulk samples were found to decrease with increasing reduction temperature. The grain size gradually increased with increasing reduction temperature due to adhesion of fine grains in a temperature range of 350 to $450^{\circ}C$. The electrical resistivity was found to increase with reduction temperature due to a decrease in carrier concentration. The Seebeck coefficient decreased with increasing reduction temperature and was in good agreement with the carrier concentration and carrier mobility. The maximum power factor, $3.3{\times}10^{-3}W/mK^2$, was measured for the non-reduction bulk TAGS-85 at $450^{\circ}C$.

• 대한전자공학회논문지TC
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• 제41권9호
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• pp.29-37
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• 2004

현재 RFID 시스템에서 해결할 가장 큰 문제 중 하나는 태그 간의 충돌로 인해 인식효율이 떨어지는 것이다. 기존의 충돌방지 알고리즘 중 프레임 알로하(Framed Slotted ALOHA)방식은 구현이 간단하다는 장점이 있으나, 태그수가 많아짐에 따라 태그 간 충돌로 인해 전체 태그를 읽는데 요구되는 슬롯의 수가 지수적으로 증가하는 단점을 갖고 있다 본 논문에서는 이 문제를 해결하기 위해서 태그수가 많을 경우 리더의 요청 메시지에 응답하는 태그수를 제한하고, 태그수가 작을 경우 동적으로 프레임 크기를 변화시켜 고속으로 태그를 인식할 수 있는 분할 응답 프레임 알로하 알고리즘(PRFSA, Partial-Response Framed Slotted ALOHA)을 제안한다 시뮬레이션 결과 PRFSA 알고리즘은 기존의 알고리즘보다 85～100% 성능이 향상됨을 보인다.

• 한국분말재료학회지
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• 제18권5호
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• pp.449-455
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• 2011

In this study, p-type $(AgSbTe_2)_{15}(GeTe)_{85}$: TAGS-85 compound powders were prepared by gas atomization process, and then their microstructures and mechanical properties were investigated. The fabricated powders were of spherical shape, had clean surface, and illustrated fine microstructure and homogeneous $AgSbTe_2$ + GeTe solid solution. Powder X-ray diffraction results revealed that the crystal structure of the TAGS-85 sample was single rhombohedral GeTe phase, which with a space group $R_{3m}$. The grain size of the powder particles increased while the micro Vickers hardness decreased with increasing annealing temperature within the range of 573 K and 723 K due to grain growth and loss of Te. In addition, the crystal structure of the powder went through a phase transformation from rhombohedral ($R_{3m}$) at low-temperature to cubic ($F_{m-3m}$) at high-temperature with increasing annealing temperature. The micro Vickers hardness of the as-atomized powder was around 165 Hv, while it decreased gradually to 130 Hv after annealing at 673K, which is still higher than most other fabrication processes.

• Fisheries and Aquatic Sciences
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• 제20권9호
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• pp.21.1-21.10
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• 2017

The aim of this study was to assess visible implant fluorescent elastomer (VIE) tagging and stress response in marine medaka, Oryzias dancena. The experimental fish were anesthetized individually and marked with red, yellow, or green elastomer at each of the following three body locations: (1) the abdomen, (2) the back, and (3) the caudal vasculature. During 12 months, the accumulated survival rates of fish in the experimental treatments were not different among red, yellow, and green elastomers. The experimental fish retained > 85% of the tags injected in the back, > 70% of the tags injected in the caudal vasculature, and > 60% of the tags injected in the abdomen (P < 0.05). An important observation was that the abdomen site was associated with poor tag retention. For all injected sites, the red and green tags were able to be detected more easily than the yellow tags when observed under both visible and UV lights. Tag readability was lower for the abdomen site than for the other sites (back and caudal vasculature). Thus, VIE tags were easy to apply to marine medaka (< 1 min per fish) and were readily visible when viewed under UV light.

• 생명과학회지
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• 제10권2호
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• pp.188-195
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• 2000

In order to understand molecular events during silk synthesis and provide genetic resources for molecular breeding, we had analyzed the cDNA library constructed from the posterior silkgland of Antheraea yamamai and partially sequenced 276 randomly selected genes from the cDNA library. Database comparisons of the expressed sequence tags (ESTs) revealed that 26 non-redundant clones showed a high similarity with previously identified genes. Among them, 17 clones exhibited a homology with previously identified insect genes and 9 clones were identical to genes that were previously identified from other organisms. A functional categorization showed that silk synthesis-defense- or stress-related genes, as well as genes involved in the metabolic pathways and in the transcriptional or translational apparatus are represented. In this report, the clone (AY479) which had high similarity with fibroin from A. pernyi was particularly analyzed in detail. The AY479 clone was carboxyl terminal region of fibroin. The 472 bp cDNA has 123 amino acids that shared 85% homology with the fibroin from A. pernyi and its deduced peptide had unique feature, that is, sites of alanine rich residues.

• 한국식품저장유통학회지
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• 제16권5호
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• pp.726-733
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• 2009

본 연구에서는 6종류의 종실에서 기름을 착유하여 조지방 함량(crude fat content) 측정 및 총 지방산 조성과 위치별 지방산 조성을 비교 분석 하였으며, triacylglycerol(TAG)의 조성과 tocopherol 함량을 분석하였다. Folch법을 이용하여 분석된 조지방 함량은 들깨 21.64%, 홍화씨 13.85%, 고추씨 9.60%, 석류씨 8.85%, 녹두 2.25%, 결명자 2.00%로 나타났다. 추출된 종실유의 지방산 분석결과 불포화 지방산인 linoleic acid(C18:2)가 81.57 wt%~46.17 wt%로 가장 높은 비중을 차지하였으며, sn-2 위치의 지방산 조성에서도 linoleic acid의 함량이 88.30 wt%~15.99 wt%로 높은 함량을 나타내었다. Triacylglycerol(TAG)의 조성은 reversed-phase HPLC를 이용하여 분석하였으며 partition number(PN)=36~48의 분포를 보였다. Total tocopherol의 함량은 석류씨에서 가장 높은 377.74 mg /100 g으로 나타났으며 이 외에 각각 녹두(141.16 mg/100 g), 결명자(107.23 mg/100 g), 고추씨(33.88 mg/100 g), 들깨(30.05 mg/100 g), 홍화씨(29.80 mg/100 g) 순으로 측정되었다.

• 한국통신학회논문지
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• 제35권1B호
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• pp.85-94
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• 2010

다수의 RFID 시스템들이 시스템 내의 RFID 태그 정보를 식별하기 위하여 동적 슬롯 알로하 프로토콜을 사용한다. 이러한 RFID 시스템에서 가장 중요한 문제점들 중의 하나는 일정 수준 이상의 정확도를 가지고 RFID 태그 개수를 추정하는 문제이다. 본 논문에서는 태그의 응답을 성공적으로 수신하였는지의 여부만을 판단할 수 있는 충돌 비 감지 리더를 기반으로 태그의 개수를 추정하는 새로운 알고리즘을 제시한다. 구체적으로, 본 논문에서 RFID 태그 개수를 추정하기 위해 무기억 성공 추정법과 교집합 기반 성공 추정법을 제시한다. 무기억 성공 추정법은 리더가 태그 정보를 수집하는 매 프레임마다 성공적으로 수집한 태그 응답의 개수를 기반으로 전체 태그 개수의 범위를 추정하는 반면, 교집합 기반 성공 추정법은 현 프레임에서 수집한 정보를 기반으로 추정된 전체 태그 개수 범위와 이전 프레임들에서 수집한 전체 태그 개수 범위의 적절한 교집합을 취함으로써 전체 태그 개수를 추정한다. 시뮬레이션 결과를 통해 교집합 기반 성공 추정법이 빠르고 정확하며 제어 가능한 태그 추정 방식임을 검증하고 그 성능이 기존의 충돌/무응답 기반 추정법의 성능에 근사함을 보인다.

• 정보보호학회논문지
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• 제20권1호
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• pp.85-94
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• 2010

RFID는 사물에 전자 태그를 부착하고 무선통신 기술을 이용하여 사물의 정보 및 주변 상황 정보를 감지하는 인식 기술로써 다양한 영역에서 이용 범위가 확대되고 있으며 관련된 보안 문제 역시 크게 대두되고 있다. 현재까지 RFID 시스템의 안전성 문제를 해결하기 위해 많은 인증 프로토콜들이 제안되었다. 본 논문에서는 ISO 18000-6 Amd1[8]의 타입 C RFID 시스템과 호환되는 기존의 RFID 인증 프로토콜[9, 10]에 대하여 스푸핑 공격이 가능함을 보이고, 그 프로토콜을 개선하여 적은 양의 추가 비용을 갖는 개선된 프로토콜을 제안한다.

• 대한의용생체공학회:의공학회지
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• 제5권1호
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• pp.85-92
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• 1984

A new architecture of the Digital Scan Converter (DSC) for the linear-scan ultrasound medical imaging systems is proposed and its hardware implementation is reported. While the conventional DSC merely displays the acquisited data and does nor allow access to the frame memory, it is possible, in the new system, to access to the frame memory for further imaging processing so as to obtain useful information for medical diagnosis. Image processing can be performed either by a special pupose processor, or by VAX 11/780. The system is made to operate asyncronously to increase the frame rate with tags assigned to the data. The proposed DSC was designed to be used without much modification for the sector scan system as well.

• 대한소아치과학회지
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• 제10권1호
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• pp.85-93
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• 1983

In one group that tested for the effects of grinding and etching on the deciduous teeth, S.E.M. examination on the ground or unground labial surface of deciduous maxillary central incisors were made after etching procedure with 40% phosphoric acid for 60 secs., 120 secs., 180 sees. each. In another group that tested for the degree of resin penetration to the ground and etched deciduous teeth, composite resin application was done to the ground deciduous maxillary central incisors that had been acid-etched for 30 secs., 60 secs., 90 sees., 120 sees., 180 secs. each. The tooth-resin specimens were cut at the middle 1/3 of the crown by 2mm thickness, and the adjacent tooth materials were demineralized by 10% hydrochloric acid, the author observed the tags of the resin replica with S.E.M.. Following results were obtained. 1. After 40% phosphoric acid etching, the unground deciduous enamel surface showed various types of etching pattern. 2. For the formation of regular micropores on deciduous enamel surface by acid etching with 40% phosphoric acid, the time over 120 secs. should be requested. 3. After 40% phosphoric acid etching, the ground deciduous enamel surface showed the same etching pattern that has been a preferential removal of prism peripheries despite different etching time. 4. On the ground group that etched over 60 secs. to 180 secs., the length of tags was $5{\mu}m$ to $8{\mu}m$, with a mean of $7{\mu}m$.