• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.383-390
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• 2020

Car-mounted MMS (Mobile Mapping System) is the most effective tool for mapping of high definition road maps(HD Map). The MMS is composed of various sensor combinations, and the manufacturing methods and processing software are different for each manufacturer, performance cannot be predicted only by the specifications of the parts. Therefore, it is necessary to judge whether each equipment is suitable for mapping through performance evaluation, and facilities for periodic performance evaluation. In this paper, we explained the MMS performance evaluation facilities built at the SOC Evaluation Research Center of Korea Institute of Civil Engineering and Building Technology and analyzed the conditions that the evaluation facilities should have through a literature survey and field tests.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.164-164
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• 2011

본 연구에서는 InAs 양자점 태양전지의 활성영역에 크기가 다른 양자점을 삽입하여 그 광학적 특성변화를 photoreflectance (PR)와 photoluminescence (PL)를 이용하여 연구하였다. 본 연구에 사용된 InAs 양자점 태양전지 구조는 n+-GaAs (100) 기판 위에 n+-GaAs buffer를 300 nm 성장 후 활성영역에 InAs 양자점과 40 nm 의 n-GaAs spacer를 이용하여 8층의 양자점을 삽입하였다. 그 위에 n-GaAs $1.14{\mu}m$와 p+-GaAs $0.6{\mu}m$, p+-AlGaAs window를 50 nm 성장하고 ohmic contact을 위하여 p+-GaAs 10 nm 성장하였다. 활성영역에 사용된 InAs 양자점의 크기는 InAs 조사량을 1.7 ML~3.0 ML까지 변화시키며 조절하였다. 양자점 태양전지의 활성영역에 삽입한 양자점의 크기에 따른 photoreflectance 측정에서 InAs 조사량이 0~2 ML 사이에서는 Franz-Keldysh oscillation (FKO)의 주기가 짧아지고 2.5 ML 이상에서는 일정한 값 가짐을 보였다. 이는 양자점의 크기가 커질수록 내부 응력에 의한 전기장의 변화에 의한 것으로 사료된다. 아울러 InAs 양자점 태양전지의 photoluminescence 측정 결과 상온에서 1.35 eV 근처에 발광이 관측되었으며 InAs 조사량이 증가할수록 발광중심 낮은 에너지쪽으로 이동함을 보였으며 태양전지 효율은 2.0 ML 인 경우 최고치를 나타내었다. InAs 조사량을 2.0 ML 이상 증가 시킨 경우는 효율이 점진적으로 감소하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.154-154
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• 2011

자발형성법(Self-assembled)을 이용한 InAs 양자점(Quantum dots)은 성장법의 고유한 물리적 한계로 길이방향에 대한 수직방향 비율(Aspect ratio, AR)이 상대적으로 작은 값을 갖는다. 기존에 보고된 바에 따르면 GaAs 기판에 형성한 InAs 양자점은 일반적으로 AR이 0.3 정도를 보인다. 이러한 높이가 상대적으로 낮은 InAs 양자점은 수직방향으로 운반자(Carrier)의 파동함수 (Wave-function) 구속이 작게 되어 나노 양자점 구조의 0차원적 특성이 저하되게 된다. 본 논문에서는 Arsenic 차단법(Interruption technique)을 이용한 수정자발형성법(Modified self-assembled method, MSAM)으로 InAs 양자점(MSAM-InAs 양자점)을 형성하고 성장 변수에 따라 광 및 구조적 특성을 평가하여 0차원 순도를 분석하였다. MSAM InAs 양자점을 성장하고 12 nm 두께의 GaAs spacer 층을 증착한 후 $600^{\circ}C$에서 30초 동안 Arsenic 분위기에서 열처리(Annealing)를 수행 한 후 다시 InAs을 증착 하였다. 이러한 과정을 5번 반복하여 높이 방향으로 형상을 개선시킨 InAs 양자점을(Vetically-controlled MSAM, VCMSAM) 성장하였다. 기존 자발형성법을 이용한 InAs 양자점과 MSAM-InAs 양자점 단일층 구조를 기준시료로 성장하였다. 상온 포토루미네슨스(Photoluminescence, PL) 실험에서 단일 MSAM InAs 양자점 및 VCMSAM 양자점 시료의 발광에너지는 각각 1.10 eV와 1.13 eV를 나타내었다. VCMSAM InAs 양자점 시료의 PL세기는 단일 MSAM 양자점보다 3.4배 증가되어, 확연히 높게 나타나는 결과를 보였다. 이러한 결과는 높이 방향으로 운반자의 파동함수 구속력이 증가하여 구속준위 (Localized states)의 전자-정공의 파동함수중첩(Overlap integral)이 개선된 것으로 설명할 수 있다. 투과전자현미경(Transmission electron microscopy) 및 원자력간 현미경(Atomic force microscopy)을 이용하여 구조적 특성을 평가하고 이를 비교 분석한 결과를 보고한다.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.227-232
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• 2015

A microarray study has been employed to understand changes of gene expression in E. coli KD43162 resistant to ampicillin, ampicillin-sulbactam, piperacillin, piperacillin-tazobactam, cefazolin, cefepime, aztreonam, imipenem, meropenem, gentamicin, tobramycin, ciprofloxacin, levofloxacin, moxifloxacin, fosfomycin, and trimethoprim-sulfamethoxazole except for amikacin using disk diffusion assay. Using Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and MALDI-TOF MS analyses, 36 kDa of outer membrane proteins (OMPs) was found to be deleted in the multidrug resistant E. coli KD 43162. Microarray analysis was used to determine up- and down-regulated genes in relation to multidrug resistant E. coli KD43162. Among the up-regulated genes, these genes were corresponded to express the proteins as penicillin-binding proteins (PBPs), tartronate semialdehyde reductase, ethanolamine utilization protein, shikimate kinase I, allantoinase, predicted SAM-dependent methyltransferase, L-glutamine: D-fructose-6-phosphate aminotransferase (GFAT), phospho-glucosamine mutase, predicted N-acetylmannosamine kinase, and predicted N-acetylmannosamine-6-P epimerase. Up-regulation of PBPs, one of primary target sites of antibiotics, might be responsible for the multidrug resistance in E. coli with increasing amount of target sites. Up-regulation of GFAT enzyme may be related to the up-regulation of PBPs because GFAT produces N-acetylglucosamine, a precursor of peptidoglycans. One of GFAT inhibitors, azaserine, showed a potent inhibition on the growth of E. coli KD43162. In conclusion, up-regulation of PBPs and GFATs with the loss of 36 kDa OMP refers the multidrug resistance in E. coli KD 43162.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.49-53
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• 1998

Direct-seeding has major advantages such as labor and cost saving by eliminating preparation of seed bed and transplanting. But, it required increased input of fertilizers and pesticides because of the extended paddy period. Direct seeding in wet paddy (DSWP) gives faster growth and more uniform seedling emergence than direct-seeding in dry paddy. This research had an objective to develop an efficient N management practices for DSWP with split application of N fertilizer. A paddy field experiment was conducted to evaluate effects of starter N and N-topdressing which was delayed N application until 5-leaf stage, with comparison to transplanting (TP). Total amount of N application were two levels; 110kg and 77kg/ha. The N applications were split four times during rice growth stages; starter, topdressing at 5-leaf stage, top dressing at tillering stage, and topdressing at panicle initiation stage. DSWP had more tillers/$m^2$ than TP, but with the delayed heading. The DSWP plots which received N-topdressing at 5-leaf stage without starter N had higher leaf area index (LAI) and leaf greenness than the TP plot. Also, these DSWP plots had high leaf-N concentration at the heading stage, as calculated from leaf chlorophyll meter readings. Rice yield in DSWP with N-topdressing at 5-leaf stage was significantly higher than that in TP and in DSWP with starter N. Energy and N use efficiency were improved in DSWP with N-topdressing at 5-leaf stage. But, there were no significant differences in grain yield between the two levels of total amounts of N applications, 77kg and 110kg/ha. We concluded that starter N could not be used effectively by rice seedlings, but topdressing N at 5-leaf stage was an efficient N management for rice growth and yield in DSWP system.

• The Journal of the Korean Society for Microbiology
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• v.14 no.1
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• pp.11-15
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• 1979

Identification of group A $\beta$-phemolytic streptococci is very important to provide an appropriate preventive measure of possible rheumatic fever and acute glomerulonephritis. For such purpose bacitracin susceptibility of streptococci because of its simplity has been most widely used despite of its occasional faulty results. Recently, a coagglutination technique was advocated using streptococcal group specific antibodies adsorbed to protein A-containing staphylococci. This study was conducted to evaluate the coagglutination technique using reagents prepared by ourselves. The specificity, reproducibility and stability were ascertained and the following results were obtained. 1. The identification by coagglutination technique using our own reagent gave the same results compared with the Lancefield precipitation technique. The result also agreed with the Phadebact grouping. 2. There were no variation in group A and B identification due to lot difference. However, there were a few discrepant results in group C and G identification which was conducted in different days with different lots of our reagent. 3. The stability of our reagents was less satisfactory compared to the commercial product. An effort to improve the stability was considered necessary. 4. For coagglutination, it was found convenient to use supernatant of Todd-Hewitt broth incubated for 24 hours. Both parafin-ringed slide glass and RPR card gave comparable results and the former could be used when the latter is not available.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.1000-1005
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• 1997

The properties of ceramics by solid-state reaction with hydroxyapatite[$Ca_{10}(PO_4)_6(OH)_2$], which was isolated from tuna bone by wet milling process were investigated. The bulk density $2.93g/cm^3$ at $1350^{\circ}C$ was close to the calculated density $3.21g/cm^3$. On X-ray measurements, the major phases were identified as hydroxyapatite at below $1300^{\circ}C$, but the whitlockite [$Ca_3(PO_4)_2$] phases were appeared due to a decomposition of hydroxyapatite with temperature. The microstructures of sintering specimens were shown as small closed pores between grain boundaries. The mean bending strength of the sintered hydroxyapatite by solid-state reaction is about 58 MPa and this value is higher than that of the articular cartilage maximum strength, 40MPa.

• Journal of Life Science
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• v.9 no.1
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• pp.84-89
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• 1999

To determine phylogenetic relatedness of four silk-producing silkmoths (B. mori, B. mandarina, A. yamamai and A. pernyi), internal coding region of arylphorin which is a storage protein in hemolymph protein of insects were amplified by polymerase chain reaction and then sequenced and compared each other. The nucleotide composition was biased toward adenine and thymine(59% A+T) and a strong bias for use of C in the third position of codons was found for Phe and Tyr. Together TTC(Phe) and TAC(Tyr) account for about 16.8% (10 for TTC and 8 for TAC) of all codon usage. The nucleotide similarity of arylphorin gene from B. mori showed 99%, 98% and 97% homology with those of B. mandarina, A. yamamai and A. pernyi, respectively. Also, the nucleotide sequence of arylphorin gene from B. mandarina showed 98% and 97% homology with those of A. yamamai and A.pernyi, respectively. Between A. yamamai and A. pernyi, the sequence homology was 97%. The deduced amino acid sequences in B. mori, B. mandarina and A. yamamai showed almost 99% homology. Although the aryphorin gene provided insufficient variability among the four insect species, A UPGMA tree is generated that supported the monophyly of silk-producing insects, with M. sexta placed basal to it. It is suggest that silk-producing insects have a close relationship and a homogeneous genetic background from comparison with those of other insects.

• Korean Journal of Environmental Agriculture
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• v.31 no.1
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• pp.16-23
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• 2012

BACKGROUND: To improve the Daechung reservoir water quality, a quantitative estimation of the delivery load from upper watershed need to be conducted prior to others. To do so, an intensive monitoring is necessary because of the complexity and uncertainty of the delivery load from uppper watershed. However, intensive monitoring need to invest much time, cost, and effort. So, many researcher have developed an equation to estimate the delivery loads. But, relatively little research has been conducted on the applicability of pre-developed equation using other sites. Therefore, the objective of this study was to evaluate application of the equation for BOD, T-N and T-P delivery load. METHODS AND RESULTS: To verify the applicability of the equation, the following equation was used; Delivery loads(kg/day)=generated pollutant loads${\times}(1-{\alpha}){\times}$(daily outflow/${\beta})^{\gamma}$. The equations could be calculated the daily delivery loads of streams without any data of water quality, only with the data of daily runoff of study sites. The equations were applied to Youngdogcheon, Chogangcheon, Bocheongcheon, Sookcheon to examine its applicability using monitoring data. The results showed that the estimated delivery loads were in a good agreement with the observed data and indicated reasonable applicability of the equations. CONCLUSION(s): Overall, the equations were satisfactory in estimation of delivery loads at upper watershed of the Daechung reservoir. Therefore, the equations could be contributed to better water quality management in the Daechung reservoir.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.245-252
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• 1990

The distributions of copepods and chaetognaths in waters off the southern coast of Korea were investigated to evaluate their reliability as indicator species of different water masses. The samples for this study were collected vertically from about 5m above the bottom at 28 stations along 8 transects in three different months, February, April, and August, 1988. The sampling gear used was 0.45-meter NORPAC plankton net fitted with 0.33mm mesh. Acartia clausi, Centropages abdominalis, and Sagitta crassa were found to be reliable indicator species of neritic cold waters; Pleuromamma gracilis, Undinula darwini, Calocalanus plumulosus, Calanopia elliptica, and Sagitta enflata were of oceanic warm waters; Temora discaudata and Centropages furcatus were of neritic warm waters. According to the cluster analyses of the species found, the distinctive area in February was divisible into two regions or water masses, the coastal and off-shore regions; in April, however, it was divisible into four regions. In August, it was divisible into three areas, further indicating the strength of the Kuroshio tributaries pushing toward the coast.