• The Journal of the Korea institute of electronic communication sciences
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• v.2 no.4
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• pp.215-221
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• 2007

IPv6 is a protocol to solve the address space limitation of IPv4 by IETF. Many transition mechanism to communicate between IPv4 and IPv6 in mixed IPv4/IPv6 network are proposed. DSTM tunneling is a mechanism that dual stack in IPv6 network is able to communicate with node in IPv4 network by dynamic allocating the IPv4 address. This mechanism supports the execution of IPv4 dependent application without modification at IPv6 network. In this paper, we explain the security vulnerability at DSTM network for DHCP attack, TEP attack, and source spoofing attack then describe the result of attacks.

• International Journal of Contents
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• v.16 no.3
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• pp.1-17
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• 2020

Human motion recognition is essential for user-centric services such as surveillance-based security, elderly condition monitoring, exercise tracking, daily calories expend analysis, etc. It is typically based on the movement data analysis such as the acceleration and angular velocity of a target user. The existing motion recognition studies are only intended to measure the basic information (e.g., user's stride, number of steps, speed) or to recognize single motion (e.g., sitting, running, walking). Thus, a new mechanism is required to identify the transition of single motions for assessing a user's consecutive motion more accurately as well as recognizing the user's body and surrounding situations arising from the motion. Thus, in this paper, we collect the human movement data through Android smartphones in real time for five targeting single motions and propose a mechanism to recognize a consecutive motion including transitions among various motions and an occurred situation, with the state transition model to check if a vulnerable (life-threatening) condition, especially for the elderly, has occurred or not. Through implementation and experiments, we demonstrate that the proposed mechanism recognizes a consecutive motion and a user's situation accurately and quickly. As a result of the recognition experiment about mix sequence likened to daily motion, the proposed adoptive weighting method showed 4% (Holding time=15 sec), 88% (30 sec), 6.5% (60 sec) improvements compared to static method.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2909-2912
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• 2009

The amines studied in this study are less reactive toward ethyl propiolate (3) in MeCN than in H$_2$O although they are 7 to 9 pK$_a$ units more basic in the aprotic solvent. The reactivity of morpholine and deuterated morpholine toward 3 is found to be identical, indicating that proton transfer occurs after rate-determining step (RDS). The fact that kinetic isotope effect is absent excludes a stepwise mechanism in which proton transfer occurs in RDS as well as a concerted mechanism in which nucleophilic attack and proton transfer occur concertedly through a 4-membered cyclic transition state (TS). Thus, the reactions have been concluded to proceed through a stepwise mechanism in which proton transfer occurs after RDS. Brønsted-type plots are linear with small ${\beta}_{nuc}$ values, i.e., ${\beta}_{nuc}$ = 0.29 in H$_2$O and ${\beta}_{nuc}$ = 0.51 in MeCN, indicating that bond formation is not advanced significantly in RDS. The small ${\beta}_{nuc}$ value also supports the conclusion drawn from the study of kinetic isotope effect.

• Journal of KIISE:Information Networking
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• v.30 no.1
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• pp.117-125
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• 2003

IPv6 (IP version 6), which was standardized by the IETF (Internet Engineering Task Force) to cope with existing IPv4 problems, needs several approaches for interoperation with IPv4. The internetworking of IPv6 with IPv4 is an important key to the deployment of the next generation Internet. As the solutions to the transition mechanism, both tunneling and translator methods have been proposed. In this paper, we analyze functional elements for implementation design of a transition mechanism based on the NAT-PT (NAT-Protocol Translation), and propose an extension algorithm that uses ports for effective use of global IPv4 addresses. The algorithm presented in this paper is a method of combining NAT-PT with Port Translation mechanism. The algorithm does not assign an IPv4 address to the host that needs IPv4 address, but allocates a single temporary IPv4 address and a port number in order to identify host.

• Journal of the Korean Society of Safety
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• v.8 no.4
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• pp.107-113
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• 1993

Small rectangular explosion chamber of its size 25cmX25cmX32cm with a circular bursting diaphram at the top was used to study the mechanism of gas explosion to fire transition phenomena, the process of ignition of solid combustibles during a gas explosion. To visulize the explosion to fire transition phenomena, transparent acryl window and high speed camera system were used. The test piece of solid combustible in this experiments was a 5cm$\times$5cm square sheet of newspaper which was placed in the explosion chamber filled with a LPG-air mixture. The mixture was ignited by an electric spark at the center of the chamber. Explosion to fire transition phenomena and the behavior of out flow and in flow of gas through the opening yielded by bursting the diaphram was visualized with shlieren system and without shlieren system. Diameter of a bursting dlaphram at the top of the explosion chamber was varied 5cm, 10cm, and 15cm, and the position of test piece were varied with 6 point. Explosion pressure was measured with strain type pressure transducer, and the weight difference of the test piece before and after each experimental run was measured. By comparing the weight difference of solid combustibles before and after the experiment and the behavior of out flow and inflow of gas after explosion, it was found that the possibility of ignition was depends on the LPG-air mixture concentration and the exposure period of test piece to the burnt gas. Test result of this experiments it was found that the main factor of this phenomena are that heat transfer to the test piece, and the pyrolysis reaction of test piece. Based on the results, the mechanism of the explosion to fire transition phenomena were inferred ; gas explosion- heat transfer to solid combustibiles ; pyrolysis reaction of solid combutibles : air inflow ; mixing of the pyroly gas with air ignition.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.309-313
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• 1990

The rates of solvolysis of trans-$[Co(N-eten)_2Cl_2)$+ (N-eten; N-ethylethylenediamine) have been investigated using spectrophotometric method in binary aqueous mixtures containing methyl alcohol, isopropyl alcohol, t-butyl alcohol, ethylene glycol and glycerol. The values of ${\Delta}H^{\neq}$ and ${\Delta}S^{\neq}$ obtained from temperature effect on the rate constants were $80{\sim}84 kJmol^{-1}$ and $- 28{\sim} - 45 JK^{-1}mol^{-1}.$ Extrema found in the variation of the enthalpy and entropy of activation with solvent composition correlated very well with extrema in the variation of the physical properties of mixture which relate to sharp change in the solvent structure. The reaction mechanism was discussed in terms of correlation diagrams involving the exess molar Gibbs function of mixing for the binary mixtures. The behavior of this cobalt(Ⅲ) complex was compared with that of t-butyl chloride. The application of free energy cycle to the process initial state to transition state in water and in the mixture showed that the solvation of transition state had dominant effect on the rates in the mixtures. It was found that $S_N1$ character was increased with increasing the content of co-solvent in the mixture.

• Journal of the Korean Ceramic Society
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• v.29 no.11
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• pp.855-862
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• 1992

Thermoelectric power, electrical conductivity and Hall effect were measured, as functions of temperature in the range of 100 to 600 K, on polycrystalline Bi4/3Sb2/3Te3 which had been prepared via uniaxial hot-pressing at different temperatures in the range of 373 K to 773 K, aiming at searching a profitable processing route to a polycrystalline thermoelectric material, a promising, viable alternative to a single crystalline one. It was found that, with increasing temperature of pressing under a fixed pressure, the material, normally a p-type prior to being hot-pressed, underwent a transition to n-type. This transition was confirmed to be due to plastic deformation during hot-pressing and interpreted as being attributed to the change of the major ionic defect BiTe' into TeBi˙at temperature high enough for structure elements mobility. Thermoelectric figure-of-merit of the hot-pressed material was discussed in connection with the p-n transition in addition to microstructure.

• BMB Reports
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• v.51 no.2
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• pp.65-72
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• 2018

The endothelial to mesenchymal transition (EndMT) is a newly recognized, fundamental biological process involved in development and tissue regeneration, as well as pathological processes such as the complications of diabetes, fibrosis and pulmonary arterial hypertension. The EndMT process is tightly controlled by diverse signaling networks, similar to the epithelial to mesenchymal transition. Accumulating evidence suggests that microRNAs (miRNAs) are key regulators of this network, with the capacity to target multiple messenger RNAs involved in the EndMT process as well as in the regulation of disease progression. Thus, it is highly important to understand the molecular basis of miRNA control of EndMT. This review highlights the current fund of knowledge regarding the known links between miRNAs and the EndMT process, with a focus on the mechanism that regulates associated signaling pathways and discusses the potential for the EndMT as a therapeutic target to treat many diseases.

• Journal of Photoscience
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• v.3 no.2
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• pp.71-76
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• 1996

Anil K. Singh, Mrunalini M. Kapil, Department of Chemistry, Indian Institute of Technology Bombay - 400076, INDIA Purple membrane (PM, $\lambda$$_{max}$ 570 nm) of H. halobium on treatment with sulphuric acid changes its colour to blue ($\lambda$$_{max}$ 608 nm). The purple chromophore can be regenerated from the blue chromophore by exogeneous addition of anions such as CI$^-$ and HPO$_4^{2-}$. Chloride ion is found to be more effective than the dibasic phosphate ion in regenerating the purple chromophore. Nevertheless, one thing common to the anion regeneration is that both CI$^-$ and HPO$_4^{2-}$ show marked pH effect. At pH 1.0 the efficiency of regeneration of the purple chromophore is greater than at pH 2.0, for the same anion concentration. Fluorescence and circular dichroic studies indicate that the proteins do not undergo drastic changes at the secondary' or tertiary structure level and the native structure is preserved during this transition. However, chromophoric-site interactions between retinal and the apoprotein are affected during this colour transition. A molecular mechanism is advanced for this transition.

• Journal of Pharmacopuncture
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• v.13 no.1
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• pp.37-43
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• 2010

Objective : Ginseng is one of most widely used herbal medicine. Ginseng showed anti-metastasis activities. However, its molecular mechanisms of action are unknown. So we want to report the wild ginseng repress which plays key roles in neoplastic epithelial-mesenchymal transition process. Methods : Treatment of the human colorectal carcinoma LOVO cells and human gastric carcinoma SNU601 cells with the increased concentrations of cultivated wild ginseng extracts resulted in a gradual decrease in the AXIN2 gene expression. Results : Metastasis-suppressor genes, maspin and nm23 was not affected by the treatment of ginseng extracts in LOVO cells. Moreover, the mountain cultivated wild ginseng or mountain wild ginseng are similar in their inhibitory effects on the expression of AXIN2 gene, but are substantially stronger than cultivated ginseng. Conclusion : We described the novel mechanism of wild ginseng-induced anti-metastasis activity by repressing the expression of AXIN2 gene that plays key roles in epithelial-mesenchymal transition process.