• 대한임베디드공학회논문지
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• 제10권3호
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• pp.171-178
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• 2015

Recently NAND flash memory has been found to be the primary cause of low performance in the smart device. NAND flash memory is different from each other the execution time of I/O operations that flash file system is required. Therefore, it is necessary to compare and analyze the flash file system I/O performance for the efficient I/O on smart device. In this paper, it was tested and analyzing the I/O performance of the YAFFS2, JFFS2, UBIFS. Experimental results most read I/O performance is good, but the writing I/O performance is not good. For UBIFS, showed a more good I/O performance compared to other flash file system.

• 한국언어정보학회지:언어와정보
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• 제5권2호
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• pp.1-8
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• 2001

Natural language string sets are known to require a grammar with a generative capacity slightly beyond that of Context Free Grammars. Proofs regarding complexity of natural language have involved particular properties of languages like English, Swiss German and Bambara. While it is not very difficult to prove that Korean is more complex than the simplest of the many infinite sets, no proof has been given of this in the literature. I identify two types of center embedding in Korean and use them in proving that Korean is not a regular set, i.e. that no FSA's can recognize its string set. The regular language i salam i (i salam ul$)^j$ michi (key ha)^k$ essta is intersected with Korean, to give {i salam i (i salam ul$)^j$ michi (key ha$)^k$ essta i $$\mid$$ j, k $\geq$ 0 and j $\leq$ k}. This latter language is proved to be nonregular. As the class of regular sets is closed under intersection, Korean cannot be regular.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1992년도 추계연구발표회 논문개요집
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• pp.38-39
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• 1992

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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• pp.892-894
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• 2005

모바일 기기가 널리 보급되면서 모바일 기기에서 멀티미디어 데이터나 데이터베이스 같은 대용량 데이터 사용에 대한 요구가 커지고 있다. 따라서 모바일 기기의 저장 공간의 한계를 극복하기 위한 노력의 하나로 iSCSI 를 이용해 모바일 기기에 원격 스토리지 서비스를 제공하는 연구가 진행되었다. 그러나 모바일 기기에 iSCSI 를 적용했을 때, 지연 시간에 민강한 iSCSI의 구조적인 특성 때문에 iSCSI 클라이언트가 서버에서 멀리 떨어진 위치로 이동하게 되면 iSCSI I/O 성능이 급격히 떨어지는 문제가 발생한다. 본 논문에서는 모바일 기기가 스토리지 서버로부터 거리가 멀어졌을 때 전송 지연시간이 증가함에 따라 iSCSI 성능이 급격하게 떨어지는 단점을 개선하기 위해 중개서버(Intermediate Target)를 이용해 iSCSI Target을 지역화하여 성능을 높이는 방안을 제안한다.

• BMB Reports
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• 제33권4호
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• pp.289-293
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• 2000

Annexin I is a 37 kDa member of the annexin family of calcium-dependent phospholipid binding proteins. Annexin I plays regulatory roles in various cellular processes including cell proliferation and differentiation. Recently we found that annexin I is a heat shock protein (HSP) and displays a chaperone-like function. In this paper we investigated the function of annexin I as an ATPase using 1 to 32 amino acids deleted annexin I (${\Delta}-annexin$ I). ${\Delta}-Annexin$ I hydrolyzed ATP as determined by thin layer chromatography. The ability of ATP hydrolysis was inhibited by ADP, GTP and GDP, but not by the AMP, GMP and cAMP. In view of the ATP hydrolyzing function of HSP, the results support the function of annexin I as a HSP.

• 대한수학회논문집
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• 제10권2호
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• pp.293-300
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• 1995

Let $R = k[y_1,\cdots,y_n] \otimes E[x_1, \cdots, x_n]$ with characteristic $k = p > 2$ (odd prime), where $$\mid$y_i$\mid$ = 2, $\mid$x_i$\mid$ = 1$ and $y_i = \betax_i, \beta$ is the Bockstein homomorphism. Topologically, $R = H^*(B(Z/p)^n,k)$. For a symmetric group $\sum_n, R^{\sum_n} = k[\sigma_1,\cdots,\sigma_n] \otimes E[d\sigma_1, \cdots, d\sigma_n]$ where d is the derivation satisfying $d(y_i) = x_i$ and $d(x_iy_i) = x_iy_i + x_jy_i, 1 \leq i, j \leq n$. We give a direct proof of this theorem by using induction.

• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.613-624
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• 1997

Dorsal root ganglion (DRG) is composed of neuronal cell bodies of primary afferents with diverse functions. Various types of ion channels present on DRG neurons may reflect those functions. In the present study, voltage-gated potassium currents in DRG neurons of neonatal rats were characterized by whole-cell voltage clamp method. Two types of delayed rectifier and three types of transient potassium currents were identified according to their electrophysiological properties. The delayed rectifier currents were named $I_{Ke}$ (early inactivating) and $I_{K1}$ (late inactivating). Steady state inactivation of $I_{Ke}$ began from -100 mV lasting until -20 mV. $I_{K1}$ could be distinguished from $I_{Ke}$ by its inactivation voltage range, from -70 mV to +10 mV. Three transient currents were named $I_{Af}$ (fast inactivation), $I_{Ai}$ (intermediate inactivation kinetics), and $I_{As}$ (slow inactivation). $I_{Af}$ showed fast inactivation with time constant of $10.6{\pm}2.0$ msec, $I_{Ai}$ of $36.9{\pm}13.9$ msec, and $I_{As}$ of $60.6{\pm}2.9$ msec at +30 mV, respectively. They also had distinct steady state inactivation range of each. Each cell expressed diverse combination of potassium currents. The cells most frequently observed were those which expressed both $I_{K1}$ and $I_{Af}$, and they had large diameters. The cells expressing $I_{Ke}$ and expressing $I_{Ke}$, $I_{Ai}$, and $I_{As}$ usually had small diameters. Judging from cell diameter, capsaicin sensitivity or action potential duration, candidates for nociceptor were the cells expressing $I_{Ke}$, expressing $I_{Ke}$ and $I_{Ai}$, and expressing $I_{Ke}$ and $I_{As}$. The types and distribution of potassium currents in neonatal rat DRG were similar to those of adult rat DRG (Gold et al, 1996b).

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2741-2747
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• 2012

A new series of 2,5-disubstituted-1,3,4-thiadiazoles 6a-i was synthesized by overnight stirring various 1,4-disubstituted thiosemicarbazides 5a-i in polyphosphoric acid followed by neutralization. The structures of newly synthesized compounds 5a-i and 6a-i were characterized by IR, $^1H$ and $^{13}C$ NMR, elemental analysis and mass spectrometric studies. All the synthesized compounds were evaluated for their urease and acetylcholine esterase inhibition activities. Thiosemicarbazides 5a-i are found to possess excellent potential for urease inhibition, more than the standard drug. Thiosemicarbazides 5a-i are more potent urease inhibitor than their cyclic analogues thiadiazoles 6a-i. Almost all of the compounds are excellent inhibitors of acetylcholine esterase. The inhibition of acetylcholine esterase of compounds 5a, 5c, 5d, 5g, 5i, 6e, 6f, 6g, and 6i is much more than that of standard drug.

• 한국환경과학회지
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• 제12권8호
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• pp.871-879
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• 2003

The complexation of co-contaminant mixtures between Ag(I) and polycyclic aromatic hydrocarbon (PAH) molecules (naphthalene, pyrene, and perylene) were investigated to quantify the equilibrium constants of their complexes and elucidate the interactions between Ag(I) and PAH molecules. The apparent solubilities of PAHs in aqueous solutions increased with increasing Ag(I) ion concentration. The values, K$_1$ and K$_2$ of equilibrium constants of complexes of Ag(I)-PAHs, were 2.990 and 0.378, 3.615 and 1.261, and 4.034 and 1.255, for naphthalene, pyrene, and perylene, respectively, The K$_1$and K$_2$ values of PAHs for Ag(I) increased in the order of naphthalene ＜ pyrene ＜ perylene and naphthalene ＜ pyrene ≒ perylene, respectively, indicating that a larger size of PAH molecule is likely to have more a richer concentration of electrons on the plane surfaces which can lead to stronger complexes with the Ag(I) ion. For the species of Ag(I)-PAH complexes, a 1:1 Ag(I) : the aromatic complex, AgAr$\^$＋/, was found to be a predominant species over a 2:1 Ag(I) : aromatic complex, Ag$_2$Ar$\^$＋＋/. The PAH molecules with four or more aromatic rings and/or bay regions were observed to have slightly less affinity with the Ag(I) ion than expected, which might result from inhibiting forces such as the spread of aromatic $\pi$ electrons over o wide molecular surface area and the intermolecular electronic repulsion in bay regions.

• 분석과학
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• 제10권1호
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• pp.60-65
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• 1997

mono-crown ether(benzo-15-crown-5)와 benzo-15-crown-5를 포함한 bis-(crown ether)s(ethylenediamine bis(4'-formylbenzo-15-crown-5))에 의한 알칼리금속과 알칼리토금속 양이온들의 용매추출을 $25^{\circ}C$, 물-클로로포름계에서 조사하였다. mono-crown ether와 bis-(crown ether)s를 사용한 경우 알칼리금속과 알칼리토금속 양이온들에 대한 추출평형상수($K_e$)와 착물형성상수($K_c$)의 크기 순위는 각각 Ca(II)>Na(I)>Sr(II)>K(I)>Mg(II)>Rb(I)와 Sr(II)>Ca(II)>K(I)>Rb(I)>Mg(II)>Na(I) 순으로 증가하였다. 이들 크기 순위는 금속 양이온의 크기 및 전자밀도효과로서 설명할 수 있었다. 또한 mono-crown ether에 비해서 bis-(crown ether)s를 사용한 경우 금속양이온들에 대한 추출효율이 좋게 나타남을 알 수 있었다.