• YAKHAK HOEJI
• /
• v.47 no.5
• /
• pp.288-292
• /
• 2003

The synthesis of new 6-exomethylene penams with substituted triazole ring was described. The 6,6-dibromopenam 5 was reacted with $CH_3$MgBr and substituted triazole 4 to afford the 6-bromo penicillanate 6, which was treated with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylene penams 8, which was oxidized to sulfones 9 by m-CPBA. The p-methoxybenzyl compounds 6∼9 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 10∼13.

• YAKHAK HOEJI
• /
• v.48 no.5
• /
• pp.303-308
• /
• 2004

The synthesis of new 6-triazole exomethylenepenams was described. The 6,6-dibromopenam 5 was reacted with $CH_3$MgBr and substituted triazole 4 to afford the 6-bromo penicillanate 6, which was treated with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylene penams 8 and 9, which were oxidized to sulfones 10 and 11 by m-CPBA. The p-methoxybenzyl compounds 6-11 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 12-17.

• Bulletin of the Korean Chemical Society
• /
• v.6 no.4
• /
• pp.238-240
• /
• 1985

Carbonato and diammine platinum(Ⅱ) complexes of resolved 6,6'-dimehtyl-2,2'-diaminobiphenyl have been prepared. The absolute configuration of the square planar platinum(Ⅱ) complexes is determined on the basis of stereospecificity of the 6,6'-dimethyl-2,2'-diaminobiphenyl ligand, circular dichroism spectra of the complexes, and nonempirical circular dichroism method.

• Journal of Chest Surgery
• /
• v.29 no.9
• /
• pp.977-982
• /
• 1996

Cardiac valve implantation was performed in 107 patients from September, 1988 to May, 1995. There were 3) men and 74 women, whose ages ranged from 19 to 75 years(mean 42.6$\pm$11.7). Mitral valve was implanted in 61 patients, double(mitral & aortic) valve were Implanted in 28 patients and aortic valve was implanted in 18 patients. Follow up was 100% complete, with 345.6 patient-years and a mean fo low up of 41 months(from 1.5 to 84 months). The total mortality was 14.9%(16 patients). The early mortality was 5.6%(6 patients) and the late mortality was 9.3%(10 patients). The overall actuarial survival was 92.6 $\pm$ 2 6% at 2 years, 88.6$\pm$3.8% at 6 years. The probability of freedom from valve failure, thromboembolism and bacterial endocarditis were 388.6 $\pm$ 3.8, 88.3 $\pm$3.9, 89.5 $\pm$3.7 at 6 years, respectively.

• Journal of Electrical Engineering and Technology
• /
• v.7 no.5
• /
• pp.765-771
• /
• 2012

$SF_6$ gas has been used as arc quenching and insulating medium for high and extra high voltage switching devices due to its high dielectric strength, its excellent arc-quenching capabilities, its high chemical stability and non toxicity. Despite of its significant contributions, the gas was classified as one of the greenhouse gas in the Kyoto Protocol. Thus, many researches are conducted to find out the replacement materials and to develop the $SF_6$ gas useless electrical equipment. This paper describes experiments on the temperature change-related breakdown characteristics of $SF_6$ gas ($SF_6$) and $SF_6$ liquid ($LSF_6$) in a model GIS(Gas-Insulated Switchgear) chamber in order to show the possibility of more stable and safe usages of $SF_6$ gas. The breakdown characteristics are classified into three stages, namely the gas stage of $SF_6$ according to Paschen's law, the coexisting stage of $SF_6$ gas with liquid in considerable deviation at lower temperature, and the stage of $LSF_6$ and remaining air. The result shows that the ability of the $LSF_6$ insulation is higher than the high-pressurized $SF_6$. Moreover, it reveals that the breakdown characteristics of $LSF_6$ are produced by bubble-formed $LSF_6$ evaporation and bubbles caused by high electric emission and the corona. In addition, the property of dielectric breakdown of $LSF_6$ is determined by electrode form, electrode arrangement, bubble formation and movement, arc extinguishing capacity of the media, difficulty in corona formation, and the distance between electrodes. The bubble formation and flow separation phenomena were identified for $LSF_6$. It provides fundamental data not only for $SF_6$ gas useless equipment but also for electric insulation design of high-temperature superconductor and cryogenic equipment machinery, which will be developed in future studies.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.7A
• /
• pp.688-696
• /
• 2010

The Proxy Mobile IPv6 (PMIPv6) is a network localized mobility management protocol that is independent of global mobility management protocols. In a single mobility domain (LMD), the mobile node (MN) is not involved in any IP mobility-related signaling and uses only its PMIPv6 home address for all its communication. Subsequently, when the MN moves into another LMD, the MN must change its PMIPv6 home address. In such a circumstance, host-based mobility signaling is activated. Thus, the nature of the network-based mobility of the PMIPv6 cannot be retained. Additionally, if the MN does not support global mobility, it cannot maintain communication with its correspondent node (CN). In this paper, we propose a solution for global mobility support in PMIPv6 networks, called Global-PMIPv6 that allows current communication sessions of a MN without mobility protocol stacks to be maintained, even when the MN moves into another LMD. Thus, Global-PMIPv6 retains the advantages of the PMIPv6 for global mobility support. We then evaluate and compare network performance between our proposed solution and PMIPv6.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.3B
• /
• pp.373-379
• /
• 2010

In this paper, we propose a novel MAS algorithm to reduce the amount of signaling and data traffics. To notify an MIPv6 host of the proposed operation, we design a new binding registration function into the MAG, and suggest the modified RS and RA messages. The binding registration in the MAG instead of the LMA is accomplished to support the PMIPv6, whereas a 1-bit N flag in the RS and RA message indicates where the MAG supports the PMIPv6 or not. Our proposed algorithm has the advantage for MIPv6 hosts in the PMIPv6 network in the viewpoints of network utilization and performance. To show the verification and better performance of the MAS algorithm, we evaluate the amount of traffic and its related performance, and compares those with performance of the normal PMIPv6. These results show that our proposed algorithm can operate efficiently and give better performance for MIPv6 hosts in the PMIPv6 network.

• Korean journal of food and cookery science
• /
• v.10 no.1
• /
• pp.63-70
• /
• 1994

Oleoresin, 6-gingerol and 6,10-gingerol: 6-paradol= 1 : 1 mixture were extracted from ginger (Zingi-her of ficinale Roscoe) and changes of its antioxidant activity by heat-treatment were studed. Oleoresin was extracted with Ethanol-Ether and 6,10-gingerol : 6-paradol(1 : 1) and 6-gingerol were extracted with Hexane and Hexan : Ether= 1 : 1, respectively, and identified on the Thin-layer Chromatograpy (TLC) plate with the solvent system of Hexane Ether(1 : 4, v/v). And oleoresin was heat-treated during 0, 10, 30, 60, 120 minutes, and 6-gingercl and 6,10-gingerol . 6-paradol=1 : 1 were heat-treated during 0, 5, 10, 20, 40 minutes, respectively, at 140$^{\circ}C$ dry oven. To compare with antioxidant activity, oleoresins were added into soybean oil at 3fo level, 6-gingerol and 6,10-gingerol : 6-paradol= 1 : 1 at 0.1% level, BHT and TBHQ at 0.02% level, respectively. All the substrates treated were stored in a incubator at 45 2$^{\circ}C$ condition. The oxidative stability was estimated by the analysises of peroxide value and conjugated diene value during storage. The results were as follows: Antioxidant activity of oleoresins were considerably high and by heat-treatment were not decreased. 6-paradol was not show the antioxidant activity. 6,10-gingerol : 6-paradol=1 : 1 provided poor protection for soybean oil. Antioxidant activity of 6-gingerol was higher than 6,10-gingerol : 6-paradol=1 : 1 and by heat-treat-ment antioxidant activity was directly decreased. Relative antioxidant effectiveness(RAE) of each antio-xidant was compared. RhR was found to decrease as follow : TBHQ>oleoresin》BHT TBHQ》BHT>6-gingerol》6,10-gingerol : 6-paradol=1 : 1.

• KSBB Journal
• /
• v.22 no.5
• /
• pp.345-350
• /
• 2007

Phosphosugars are found in all living organisms and are commercially valuable compounds with possible applications in the development of a wide range of specialty chemicals and medicines. In carbohydrate metabolism, fructose 6-phosphate (F6P) is an essential intermediate formed by phosphorylation of 6' position of fructose in glycolysis, gluconeogenesis, pentose phosphate pathway and Calvin cycle. In glycolysis, F6P lies within the glycolysis metabolic pathway and is produced by isomerisation of glucose 6-phosphate. For large-scale production, F6P could be produced from starch using many enzymes such as pullulanase, starch phosphorylase, isomerase and mutase. In enzymatic reactions carried out at high temperatures, the solubility of starch is increased and microbial contamination is minimized. Thus, thermophile-derived enzymes are preferred over mesophile-derived enzymes for industrial applications using starch. Recently, we reported the production of glucose 1-phosphate (G1P) from starch by Thermus caldophilus GK24 enzymes. Here we report the production of F6P from starch through three steps; from starch to glucose 1-phosphate (glucan phosphorylase, GP), then glucose 6-phosphate (phosphoglucomutase, GM) and then F6P (phosphoglucoisomerase, GI). Using 200 L of 1.2% soluble starch solution in potassium phosphate buffer, 1,253 g of G1P were produced. Then, 30% yields of F6P were attained at the optimum reaction conditions of GM : G1 (1 : 2.3), 63.5$^{\circ}C$, and pH 6.85. The optimum conditions were found by response surface methodology and the theoretical values were confirmed by the experiments. The optimum starch concentrations were 20 g/L under the given conditions.

• International Journal of Advanced Culture Technology
• /
• v.2 no.1
• /
• pp.1-13
• /
• 2014

In next-generation wireless networks, provisioning of IP-based network architecture and seamless transmission services are very important issues for mobile nodes. For this reason, a mobility management mechanism to support global roaming is highly regarded. These technologies bring a broader life by using a global roaming account through the connection of multiple devices or technology to mobile users; they also provide real-time multimedia services. This paper presents a comprehensive performance analysis of fast handover for hierarchical mobile IPv6 (F-HMIPv6), hierarchical mobile IPv6 (HMIPv6), Proxy Mobile IPv6 (PMIPv6), and fast Proxy Mobile IPv6 (FPMIPv6) using the fluid-flow model and random-walk model. As a result, the location update cost of the PMIPv6 and FPMIPv6 is better than that of HMIPv6 and F-HMIPv6. These results suggest that the network-based mobility management technology is superior to the hierarchical mobility management technology in the mobility environment.