• Journal of the Korean Ceramic Society
• /
• v.30 no.4
• /
• pp.289-298
• /
• 1993

Properties in terms of the variation of the glass compositions, which were density (p), molar volume(Vm), atom/ion packing density (Dp), refractive index (nD), transformation temperature (Tg), dilatometric softening point (Td), thermal expansion coefficient (α), Young's modulus (E), and knoop hardness (KHN) were investigated in CaO-SiO2 glasses and CaO-P2O5-SiO2 glasses containing less than 10mole% of P2O5. Those properties were measured by density measurement kit, Abbe refractometer, dilatometer, ultrasonic pulse echo equipment, and micro hardness tester. When CaO content was increased in CaO-SiO2 glasses, p, Dp, nD, Tg, Td, α, E and KHN were increased, while Vm was decreased. When P2O5 was added to the CaO-SiO2 glasses with constant CaO/SiO2 ratio as 1.07, p, Dp, nD, Tg, Td, α, E and KHN were decreased, while Vm was increased. When the amount of P2O5 in glasses was kept constant, the changes of the properties with variation of CaO content in the CaO-P2O5-SiO2 glasses were very similar to those of CaO-SiO2 glasses. These phenomena could be explained by the structural role of P2O5 in the CaO-P2O5-SiO2 glasses, which was polymerization of siicate structures and resulted in [PO4] monomer structure in glasses. Due to this structural characteristics, the bond strength and packing density were changed with compositions. Proportional relationships between 1) np and Dp, 2) Tg, Td, α and CaO content, 3) E and Vm-1, and 4) KHN and P2O5 content were evaluated in this investigation.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.2
• /
• pp.128-135
• /
• 2009

Acinetohacter baumannii BD5 was isolated from waters of Baek-du mountain, and the lipase gene was cloned using a PCR technique. The deduced amino acid sequence of the lipase and lipase chaperone were found to encode proteins of 325 aa and 344 aa with a molecular mass of 35 kDa and 37 kDa, respectively. The lipase gene was cloned and expressed in Escherichia coli BL21(trxB) as an inclusion body, which was subsequently solubilized by urea, and then purified using Ni-affinity chromatography. After being purified, the lipase was refolded by incubation at $4^{\circ}C$ in the presence of a 1:10 molar ratio of lipase:chaperone. The maximal activity of the refolded lipase was observed at a temperature of $35^{\circ}C$ and pH 8.3 when p-NP caprate(C10) was used as a substrate; however, 28% of the activity observed at $35^{\circ}C$ was still remaining at $0^{\circ}C$. The stability of the purified enzyme at low temperatures indicates that it is a cold-adapted enzyme. The refolded lipase was activated by $Ca^{2+},\;Mg^{2+},\;and\;Mn^{2+}$, whereas $Zn^{2+}\;and\;Cu^{2+}$ inhibited it. Additionally, 0.1% Tween 20 increased the lipase activity by 33%, but SDS and Triton X-100 inhibited the lipase activity by 40% and 70%, respectively.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.278.1-278.1
• /
• 2014

Organic materials have been explored as the gate dielectric layers in thin film transistors (TFTs) of backplane devices for flexible display because of their inherent mechanical flexibility. However, those materials possess some disadvantages like low dielectric constant and thermal resistance, which might lead to high power consumption and instability. On the other hand, inorganic gate dielectrics show high dielectric constant despite their brittle property. In order to maintain advantages of both materials, it is essential to develop the alternative materials. In this work, we manufactured nanocomposite gate dielectrics composed of organic material and inorganic nanoparticle and integrated them into organic TFTs. For synthesis of nanocomposite gate dielectrics, polyimide (PI) was explored as the organic materials due to its superior thermal stability. Candidate nanoprticles (NPs) of halfnium oxide, titanium oxide and aluminium oxide were considered. In order to realize NP concentration dependent electrical characteristics, furthermore, we have synthesized the different types of nanocomposite gate dielectrics with varying ratio of each inorganic NPs. To analyze gate dielectric properties like the capacitance, metal-Insulator-metal (MIM) structures were prepared together with organic TFTs. The output and transfer characteristics of organic TFTs were monitored by using the semiconductor parameter analyzer (HP4145B), and capacitance and leakage current of MIM structures were measured by the LCR meter (B1500, Agilent). Effects of mechanical cyclic bending of 200,000 times and thermally heating at $400^{\circ}C$ for 1 hour were investigated to analyze mechanical and thermal stability of nanocomposite gate dielectrics. The results will be discussed in detail.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.7
• /
• pp.9-16
• /
• 2008

For the efficient routing on a Sensor Network, one may consider a deployment problem to interconnect the sensor nodes optimally. There is an analogous theoretic problem: the Steiner Tree problem of finding the tree that interconnects given points on a plane optimally. One may use the approximation algorithm for the problem to find out the deployment that interconnects the sensor nodes almost optimally. However, the Steiner Tree problem is to interconnect mathematical set of points on a Euclidean plane, and so involves particular cases that do not occur on Sensor Networks. Thus the approach of using the algorithm does not make a proper way of analysis. Differently from the randomly given locations of mathematical points on a Euclidean plane, the locations of sensors on Sensor Networks are assumed to be physically dispersed over some moderate distance with each other. By designing an approximation algorithm for the Sensor Networks in terms of that physical property, one may produce the execution time and the approximation ratio to the optimality that are appropriate for the problem of interconnecting Sensor Networks.

• KSBB Journal
• /
• v.26 no.5
• /
• pp.393-399
• /
• 2011

Bacillus subtilis natto producing high level of a fibrinolytic enzyme was selected and Ultra Nattokinase$^{(R)}$ was manufactured by fermentation and purification. It was performed the evaluation of the antithrombotic effect of Ultra Nattokinase$^{(R)}$ (20,000 FU/g) with rat blood plasma. The maximum aggregation (inhibition ratio) was 71% (0%), 69% (2.8%), 62% (12.7%), 16% (77.5%) and 9% (87.3%), respectively, in the order of 0, 5, 10, 50 and 100 mg/mL of Ultra Nattokinase$^{(R)}$ solutions. Ultra Nattokinase$^{(R)}$ had antithrombotic effect, which was associated with the suppression of collagen-induced platelet aggregation. Ultra Nattokinase$^{(R)}$ in the topic of the FDP (fibrinogen degradation products) in blood coagulation tests showed a significant increasing trend. And based on the daily record of meal 39 people of ITT (what ?) group consisted with 19 people of NP (what ?) group and 20 people of PN (what ?) group except four people, two people who took vitamin K affecting the experiment and two people who took alcohol, finding to be taken Ultra Nattokinase$^{(R)}$ showed an increase in the FDP value after four weeks. In addition, FDP value of 41 people of ITT group except two people having metabolic syndrome was increased by Ultra Nattokinase$^{(R)}$.

• Journal of Communications and Networks
• /
• v.18 no.4
• /
• pp.559-566
• /
• 2016

Software defined network (SDN) can effectively improve the performance of traffic engineering and will be widely used in backbone networks. Therefore, new energy-saving schemes must take SDN into consideration; this action is extremely important owing to the rapidly increasing energy consumption in telecom and Internet service provider (ISP) networks. Meanwhile, the introduction of SDN in current networks must be incremental in most cases, for technical and economic reasons. During this period, operators must manage hybrid networks in which SDN and traditional protocols coexist. In this study, we investigate the energy-efficient traffic engineering problem in hybrid SDN/Internet protocol (IP) networks. First, we formulate the mathematical optimization model considering the SDN/IP hybrid routing mode. The problem is NP-hard; therefore, we propose a fast heuristic algorithm named hybrid energy-aware traffic engineering (HEATE) as a solution. In our proposed HEATE algorithm, the IP routers perform shortest-path routing by using distributed open shortest path first (OSPF) link weight optimization. The SDNs perform multipath routing with traffic-flow splitting managed by the global SDN controller. The HEATE algorithm determines the optimal setting for the OSPF link weight and the splitting ratio of SDNs. Thus, the traffic flow is aggregated onto partial links, and the underutilized links can be turned off to save energy. Based on computer simulation results, we demonstrate that our algorithm achieves a significant improvement in energy efficiency in hybrid SDN/IP networks.

• The Korean Journal of Pain
• /
• v.36 no.1
• /
• pp.84-97
• /
• 2023

Background: The concept of high-impact chronic pain (HICP) has been proposed for patients with chronic pain who have significant limitations in work, social life, and personal care. Recognition of HICP and being able to distinguish patients with HICP from other chronic pain patients who do not have life interference allows the necessary measures to be taken in order to restore the physical and emotional functioning of the affected persons. The aim was to reveal the risk factors and predictors associated with HICP. Methods: Patients with chronic pain without life interference (grade 1 and 2) and patients with HICP were compared. Significant data were evaluated with regression analysis to reveal the associated risk factors. Receiving operating characteristic (ROC) analysis was used to evaluate predictors and present cutoff scores. Results: One thousand and six patients completed the study. From pain related cognitive processes, fear of pain (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.87-0.98; P = 0.007) and helplessness (OR, 1.06; 95% CI, 1.01-1.12; P = 0.018) were found to be risk factors associated with HICP. Predictors of HICP were evaluated by ROC analysis. The highest discrimination value was found for pain intensity (cut-off score > 6.5; 83.8% sensitive; 68.7% specific; area under the curve = 0.823; P < 0.001). Conclusions: This is the first study in our geography to evaluate HICP with measurement tools that evaluate all dimensions of pain. Moreover, it is the first study in the literature to evaluate predictors and cut-off scores using ROC analysis for HICP.

• Tuberculosis and Respiratory Diseases
• /
• v.42 no.6
• /
• pp.838-845
• /
• 1995

The determination of ADA(adenosine deaminase) activity in pleural fluid is useful in differental diagnosis of pleural effusion. The conventional method of determining ADA activity used by Giusti was influenced by contamination of ammonia. Additionally, because Giusti's method was mannual method a determining the ADA activities in sample, was not easily automated. In 1993, Oosthuizen HM with collegues developed simple kinetic method for determining ADA activity. It was reliable and suiable method for automation. In this study, we have measured ADA activity in 162 patients with various pleural effusion by Hitachi 747 autoanalyser using the Oosthuizen kinetic method for the purpuse of determination of new diagnostic cut-off value for the tuberculous effusion and evaluation of the correlation between the conventional method and new automated method. This new method of an enzymatic reaction involves 2, 6-dichlorophenolindophenol dye(DICP), adenosine, xanthine oxidase(XO), and nucleoside phosphorylase(NP). The results were as follows: 1) The mean pleural ADA activity of the tuberculous effusion was $52.53{\pm}16.43\;U/L$ and significantly higher than that of other groups(p<0.001). If the diagnostic cut-off value of pleural ADA activity for tuberculous effusion is above 30 U/L, the sensitivity is 96% and the specificity is 90%. 2) The mean pleural to serum ADA activity ratio of the tuberculous effusion was $2.29{\pm}0.96$ and it was also significantly higher than that of other pleural groups(p<0.001). If the diagnostic cut-off value of pleural to serum ADA activity ratio is 1.5, the sensitivity is 80% and the specificity is 88% in the diagnosis of tuberculous pleural effusion. 3) The new kinetic method is correlates well to Giuisti's conventional method(r=0.971). In conclusion, the new kinetic method described is easily automated and seems to be suitable for the routine determination of ADA activity.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.63 no.3
• /
• pp.175-185
• /
• 2018

The aim of this study was to evaluate the variation of growth and quality characteristics in colored rice from 178 accessions and to develop useful, basic rice breeding data by classifying these germplasm characteristics via principal component (PC) analysis. The coefficient of variation of the 178colored rice accessions were the highest for panicle length (PL) and protein contents, followed by length-width ratio (LWR), 1000-grain weight (TGW), culm length (CL), and amylose contents, whereas the lowest was for the number of panicles per hill (NP), which is a yield component. The results from the PC analysis exhibited eigenvalues and contributions respective to each PC as follows: PC1, 2.06 and 29.49%; PC2, 1.31 and 18.75%; PC3, 1.21 and 17.36%; PC4, 1.01 and 14.38%. The eigenvalues of four PCs were over 1.0, and their cumulative contributions were 79.98%, which completes the necessary condition for evaluation of the 178 colored rice accessions. Cluster analysis showed cluster I as the largest, which included 79 accessions, while clusters II, III, IV, V, VI, and VII comprised 46, 19, 13, 4, 8, and 9 accessions, respectively. Moreover, dark brown accessions were dispersed in clusters I and II, and many resources of purple seed coat color were found in clusters V, VI, and VII. Particularly, cluster V had resources of only black and purple seed coat colors. Resources of cluster VII were found to have a relatively small average CL, PL, and LWR; notably, cluster V had the smallest average TGW, and cluster IV the lowest NP but the highest TGW. Finally, considering the yield potential, growth characteristics, heading stage, and color during breeding of colored rice, we obtained the following conclusions: cluster VII is suitable for breeding of colored rice; cross breeding among clusters I, II, and VII has a high yield potential; and it is possible to produce a superior color by cross breeding plants from cluster V and VI.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.11
• /
• pp.1559-1563
• /
• 2009

Scaled-up production of oil containing diacylglycerol (DAG), so called diacylglycerol-oil, was produced by lipase-catalyzed reaction. Mixture of soybean oil and glyceryl monooleate with 1:2 molar ratio was esterified with Lipozyme RMIM in a batch-type reactor at 55$^{\circ}C$ and 300 rpm during 6 hr. After short-path distillation for removal of monoacylglycerol and free fatty acid as reaction by-products, diacylglycerol-oil mainly consisted of DAG (29 area%) and TAG (71 area%). The major compositional fatty acids in diacylglycerol-oil were oleic (44.36 wt%), and linoleic acids (37.36 wt%). Acid value and iodine value of diacylglycerol-oil were 0.13 and 112.6, respectively. Solid fat content (SFC) of diacylglycerol-oil was observed after differential scanning calorimetry (DSC) analysis in which three melting peaks at -25.0, 0.1, and 11.2$^{\circ}C$ were shown.