• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1110-1111
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• 2006

[ $Ti_3SiC_2$ ] was coated with $Al_2O_3$, MgO and $SiO_2$ respectively by sol-gel method and cured at 900 and $1200^{\circ}C$. The coated oxides did not react with $Ti_3SiC_2$ at $900^{\circ}C$ but reacted with it to form $TiC_x$ at $1200^{\circ}C$. The specimen coated with $SiO_2$ at $900^{\circ}C$ formed a dense protecting layer and showed the best oxidation resistance at $800^{\circ}C$ in air. However, the dense protecting layers did not form in $Al_2O_3$ and MgO coated specimens cured even at $900^{\circ}C$. MgO coated specimen showed the worst improvement in the oxidation resistance because the reactivity of MgO with $Ti_3SiC_2$ was highest. On the other hand, the electrical conductivities were measured in MgO and $Al_2O_3$ coated specimens to have TiCx but could not be measured in the $SiO_2$ coated ones because of the nonconductive dense protected layers.

• Parasites, Hosts and Diseases
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• 제38권4호
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• pp.257-261
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• 2000

This study was focused on the effects of microfilament inhibitor, Cytochalasin D (CD) on the invasiveness of sporozoites of Cryptosporidiun spp. into the host cells. MDCK and AGS cell lines were used as host cells for C. parvum and C. muris, respectively. When MDCK cells were pretreated with CD for 1 hr before inoculation of the sporozoites, C. parvum infection was significantly inhibited when compared to the control cells. These inhibitory effects of CD on the rate of infection were dose-dependent. In addition, C. muris infection was hampered when AGS cell lines were pretreated with CD. However, the capability of invasiveness of the sporozoites into the host cells was not greatly influenced by the pretreatment of sporozoites with CD before infection. These results suggest that microfilaments of host cells, rather than parasites, play an important role for the invasion of Cryptosporidium spp.

• 한국자기공명학회논문지
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• 제19권1호
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• pp.18-22
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• 2015

The structural geometry of $[N(CH_3)_4]_2CdCl_4$ in a hexagonal phase is studied by $^1H$ MAS NMR, $^{13}C$ CP/MAS NMR, and $^{14}N$ NMR. The changes in the chemical shifts for $^{13}C$ and $^{14}N$ in the hexagonal phase are explained by the structural geometry. In addition, the temperature dependencies of the spin-lattice relaxation time in the rotating frame $T_{1{\rho}}$ for $^1H$ MAS NMR and $^{13}C$ CP/MAS NMR are measured.

• 한국식품조리과학회지
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• 제24권5호
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• pp.617-625
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• 2008

In this study, we evaluated changes in the quality characteristics of Godulbaegi kimchi during storage at $20^{\circ}C$ and $5^{\circ}C$. The pH and reducing sugar of Godulbaegi kimchi decreased, and the total acidity and color differences increased with increasing storage time at both temperatures. The vitamin C contents of the Godulbaegi kimchi decreased during the first 15 days of storage at $20^{\circ}C$, then increased for 18 days. The total dietary fiber contents were significantly higher in the fresh Godulbaegi kimchi than in the fermented Godulbaegi kimchi samples. Antioxidative activity was significantly higher in the fresh Godulbaegi kimchi than in the fermented kimchi.

• 대한수학회보
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• 제61권4호
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• pp.907-915
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• 2024

Let f be an integral quadratic form in k variables, F the Gram matrix corresponding to a ℤ-basis of ℤ^k. For r ∈ F^-1ℤ^k, a rational number n with f(r) ≡ n mod ℤ and a positive integer c, set N_f(n, r; c) := #{x ∈ ℤ^k/cℤ^k : f(x + r) ≡ n mod c}. Siegel showed that for each prime p, there is a number w depending on r and n such that N_f(n, r; p^ν+1) = p^k-1N_f(n, r; p^ν) holds for every integer ν > w and gave a rough estimation on the upper bound for such w. In this short note, we give a more explicit estimation on this bound than Siegel's.

• 한국세라믹학회지
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• 제42권1호
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• pp.33-36
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• 2005

저온 소결용 PMN-PT-BT분말을 $850^{circ}C/2h$ 소결할 때 승온 속도를 분당 5, 10, $20^{circ}C$로 변화하며 물성에 미치는 영향을 조사하였다. PbO(응점 $886^{circ}C$)의 휘발이 미미한 소결온도에서는 분당 $5^{circ}C$로 승은하여 소결한 것이 승온 속도 $10^{circ}C$나 $20^{circ}C$의 경우에 비하여 보다 균일한 미세구조를 나타내며, 소결밀도 $7.93g/cm^{3}$, 실온 유전을 15300, 유전손실 $0.92\%의 우수한 유전 특성을 나타내었다.

• 한국결정학회지
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• 제8권1호
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• pp.59-63
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• 1997

화합물내에 존재하는 다음 7가지 수소원자의 이상적인 위치들의 한가지 계산법을 보였다. (1) 3급 C-H, (2) 2급 C-H, (3) 1급 C-H, (4) 방향환 C-H와 N-H, (5) 수산기 O-H, (6) 말단평면내의 2개의 수소 (7) 선형인 X-C-H를 갖는 아세틸렌 C-H.

• 한국식품영양과학회지
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• 제37권1호
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• pp.66-71
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• 2008

반응표면분석법을 통하여 홍차의 침출 온도와 시간에 따른 침출물의 기능성 성분과 항산화성을 모니터링하고 최적 침출조건을 예측하였다. 수용성 성분의 침출수율, 환원당, 총 페놀, 총 플라보노이드 함량 등은 침출온도가 높아지고 침출시간이 길어짐에 따라 증가되는 경향을 보였고, $78.28{\sim}87.08^{\circ}C$와 $3.97{\sim}4.27$분으로 침출할 경우 최대값을 얻을 수 있었다. 비타민 C는 침출온도가 높거나 낮고 침출시간이 길거나 짧을 경우에 감소하였으며 $61.29^{\circ}C$와 2.68분에서 가장 높았다. 전자공여능은 침출온도가 높거나 낮고 침출시간이 길어짐에 따라 감소하였고 $68.30^{\circ}C$와 0.54분에서 최대값을 나타내었다. 이로써 홍차 티백의 기능성 관련 성분을 고려한 최적 침출조건은 침출온도 $63{\sim}79^{\circ}C$와 침출시간 $1.5{\sim}2.1$분으로 예측되었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 하계종합학술대회 논문집(1)
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• pp.171-174
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• 2004

Packet classification is an essential architectural component in implementing the quality-of-service (QoS) in today's Internet which provides a best-effort service to ail of its applications. Multiple header fields of incoming packets are compared against a set of rules in packet classification, the highest priority rule among matched rules is selected, and the packet is treated according to the action of the rule. In this Paper, we proposed a new packet classification scheme based on parallel multiple hashing on tuple spaces. Simulation results using real classifiers show that the proposed scheme provides very good performance on the required number of memory accesses and the memory size compared with previous works.

• The Plant Pathology Journal
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• 제17권4호
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• pp.194-200
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• 2001

Chrysanthemum stunt viroid (CSVd) ws identified in chrysanthemum cv. Chunkwang showing symptoms of stunt with leaf distortion (K1) and stunt with chlorosis of leaves (K2) collected from the main cultivation area of Masan, Kyongnam province in Korea. The specific RNAs related with the diseased chrysanthemums were detected. Full-length 354 bp CSVd cDNAs were amplified from infected tissue by reverse transcription and polymerase chain reaction using a pair of primers specific for CSVd sequence. The amplified cDNA products were analyzed by agarose gel electrophoresis and the specific cDNAs were cloned. Nucleotide sequences of the two CSVd isolates K1 and K2 varied. Phylogenetic analysis of the nucleotide sequences of CSVd isolates indicated that K1 was closely related with J2 and Am 2 isolates. K1 and K2 were transmitted by grafting to Dendranthema grandiflorum cv. Mistletoe, Gynura aurantiaca, and Lycopersicon esculentum cv. Rutgers. This is the first report of CSVd in D. grandiflorum in Korea.