• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.261-264
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• 2000

The purpose of this study is to research and develop solid polymer electrolyte(SPE) for Li polymer battery. This paper describes temperature dependence of conductivity, impedance spectroscopy, electrochemical properties of PAN/PVDF electrolytes as a function of a mixed ratio. PAN/PVDF based polymer electrolyte films were prepared by thermal gellification method of preweighed PAN/PVDF, plasticizer and Li salt. By adding PVDF and as a function of plasticizer mixed ratio to PAN-LiClO4 electrolyte, its conductivity was higher than that of PAN-$LiClO4_4$ electrolyte. The conductivity of PAN/PVDF electrolytes was $10^{-3}S/cm$. $10PAN10PVDFLiClO_4PC_5EC_5$ electrolyte shows the better conductivity of the others. Steady state current method and ac impedance used for the determination of transference numbers in PAN/PVDF electrolyte film. The transference number of $10PAN10PVDFLiClO_4PC_5EC_5$ electrolyte is 0.45.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.741-749
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• 2008

Many small-scale ponds that serve as ecological habitat, recreation and irrigation are faced to eutrophication problem, which causes aesthetic nuisance and ultimately loss of their functions. Thus accurate evaluation of the trophic state of these ponds is essential to provide rational information to the stakeholders so that they can develop effective management actions. In this study, the trophic state of a small pond (Wonheung) that experiencing water quality degradation due to vicinity land development was assessed using various Trophic State Indexes (TSIs) and statistical analysis including Principal Components Analysis (PCA) based on the field monitoring data obtained from May to December, 2007. The results showed that the pond is under eutrophic state with average total nitrogen (T-N) and total phosphorus (T-P) concentrations of $708.1{\mu}g/L$ and $59.3{\mu}g/L$, respectively. The factor loading plot obtained from PCA showed distinct two influencing factors, PC 1 and PC 2. PC 1 was grouped by T-P, Chlorophyll a (Chl-a), suspended solids (SS), TN/TP ratio, and transparency that all strongly related to the eutrophication state, while PC 2 by temperature, conductivity, dissolved oxygen (DO) and turbidity that explains the seasonal water quality variations. The limiting factor was identified as light rather than phosphorus by both T-N/T-P ratio and TSI indexes analysis. The results and methodology adopted in this study can be used for water quality assessment for other small ponds and lakes.

• Journal of The Korean Astronomical Society
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• v.41 no.5
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• pp.139-145
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• 2008

The molecular cloud, embedding AFGL 2591, has a "head-and-tail" structure with a total mass of ${\sim}\;1800\;M_{\odot}$, about half of the mass (${\sim}\;900\;M_{\odot}$) in the head (size ${\sim}\;1.2\;pc$ in diameter), and another half in the envelope (${\sim}\;3.5\;pc$ in the east-west direction). We found a new cloud in the direction toward north-east from AFGL 2591 (projected distance ${\sim}\;2.4\;pc$), which is probably associated with the AFGL 2591 cloud. The $^{12}CO$ spectrum clearly shows a blue-shifted high-velocity wing at around the velocity $-20\;{\sim}\;-10\;km\;s^{-1}$, but it is not clear whether this high-velocity component has a bipolar nature in our observations. The observed CN spectra also show blue-shifted wing component but the existence of the red-shifted component is not clear, either. In some CN and HCN spectra, the highvelocity components appear as a different velocity component, not a broad line-wing component. The dense cores, traced by CN and HCN, exist in the 'head' of the AFGL 2591 cloud with an elongated morphology roughly in the north-south direction with a size of about 0.5 pc. The abundance ratio between CN and HCN is found to be about 2 - 3 within the observed region, which may suggest a possibility that this core is being affected by the embedded YSOs or by possible shocks from outside.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.539-543
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• 2016

Background: It is well known that peritoneal carcinomatosis (PC) from colorectal cancer (CRC) is associated with a poor prognosis. However, data on the prognostic significance of modern chemotherapy containing bevacizumab, cetuximab or panitumumab are not available. Materials and Methods: This retrospective review concerned 526 patients with metastatic CRC who were classified into two groups according to the presence or absence of PC, and were treated with systemic chemotherapy, with or without bevacizumab or anti-EGFR antibodies. The genetic background, in particular KRAS, BRAF, and PIK3CA gene mutations, and overall survival (OS) were compared between the two groups. Results: The median OS values were 23.3 and 29.1 months for PC and non-PC patients, respectively (hazard ratio [HR]=1.20; p=0.17). Among all patients, tumor location, number of metastatic sites and BRAF mutation status were significant prognostic factors, whereas the presence of PC was not. In the PC group, chemotherapy with bevacizumab resulted in a significantly longer OS than forchemotherapy without bevacizumab (HR=0.38, p<0.01), but this was not the case in the non-PC group (HR=0.80, p=0.10). Furthermore, the incidence of the BRAF V600E mutation was significantly higher in PC than in non-PC patients (27.7% versus 7.3%, p<0.01). BRAF mutations displayed a strong correlation with shorter OS in non-PC (HR=2.26), but not PC patients (HR=1.04). Conclusions: Systemic chemotherapy, especially when combined with bevacizumab, improved survival in patients with PC from CRC as well as non-PC patients. While BRAF mutation demonstrated a high frequency in PC patients, but it was not associated with prognosis.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.72-79
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• 2006

1,225 healthy day-old avian broiler chicks were used to investigate the effects of activated charcoal (AC, made from willow tree), hydrated sodium calcium aluminosilicates (HSCAS) and esterified glucomannan (EGM) supplementation on broiler performance, blood profiles and meat characteristics when less moldy or moldy corn was included to formulate seven isocaloric and isonitrogenous diets: Positive Control (less moldy corn diet, PC), PC+2% AC, Negative Control (moldy corn, NC), NC+0.05% EGM, NC+0.1% EGM, NC+0.5% HSCAS and NC+1% AC. PC+2% AC resulted in lower growth rate, poorer feed conversion ratio (FCR), more leg problems and higher mortality of birds than those fed PC diet (p<0.05). Inclusion of 0.05% EGM, 0.1% EGM, 0.5% HSCAS and 1% AC in NC diet did not improve average daily weight gain (ADG) or affect feed intake of birds during the first or the second three-week periods. However, 0.05% EGM tended to (p>0.05) and 0.1% EGM significantly (p<0.05) improved FCR during the first three-week period. Breast meat of NC birds had higher Minolta $L^*$ values (white) but lower $a^*$ (reddish) and $b^*$ (yellowish) values (p<0.01) than the PC birds. Addition of 0.05% EGM and 0.1% EGM in NC diet reduced the $L^*$ values (p<0.05), improved $a^*$ and $b^*$ values (p<0.05) of breast meat of birds fed NC diet, but had no effect on meat color when 0.5% HSCAS or 1% AC was included (p>0.05). Relative weight of liver to body was reduced by feeding NC diet (p<0.05) and could not be normalized by different mycotoxin adsorbents (p>0.05) to the ratio of the PC birds. Relative weight of cholecyst of NC birds was increased compared with PC birds and could only be normalized by addition of 0.05% EGM and 1% AC (p<0.05) in NC diet. NC birds had lower serum albumin level than the PC birds (p<0.05) and addition of 0.05% EGM or 1% AC in NC diet did normalize serum albumin level. Addition of 0.5% HSCAS in NC diet further reduced serum albumin, globulin, total protein and uric acid levels (p<0.05). It was concluded that lower FCR during the first three-week period of growth and deterioration of meat quality observed in bird fed moldy corn with moderate T2 and fuminisin contamination and damaged nutrients and pigment availability, might be improved by dietary supplementation of 0.05% to 0.1% EGM, but not by 1% AC or 0.5% HSCAS supplementation.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.595-599
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• 1989

The effects of phosphatidic acid(PA) on the activity of phospholipase D were examined in detail. The enzyme activity was examined in the liposome system containing phosphatidylcholine and PA, which was suspended in a desired buffer solution by ultrasonication. The substrate of large unilamella vesicle (LUV) state by ultrasonication was more effective on the enzyme activity than that of multilamella vesicle(MLV) by water-bath type sonication. The most effective molar ratio of PC-PA liposome for enzyme activity was found to be 1:0.7. The other optimum conditions were found 5 mM $Ca^{2+}$ ion, pH 6.6, and incubation temperature of $27^{\circ}C. K_m \;and \;V_{max}$ values were estimated to be 1.43 mM and 0.8 $nmole/min/{\mu}g$ protein respectively. These properties in a PC-PA liposome system were compared with those in a PC-SDS mixed micelle system. The effects of other phospholipids and organic phosphates on the enzyme activity were also examined.

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.463-468
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• 2010

The polycarboxylic (PC) type concrete superplasticizer was synthesized. The effects of ethylene oxide group number and its molecular weight on the properties of the polycarboxylic type concrete superplasticizer and the concrete motar properties were studied. To investigated of the interfacial properties of the premixed-concrete with the superplasticizer, the type and the amount of polyethylene glycol, meta acrylate added, and type of the initialization agent were studied. Also the interfacial properties of the superplasticizer aqueous phase, the wettability on the cement particle, the fluidity of the cement mortar, and the strength properties of the concrete were measured. For a high fluidity of the cement mortar and a high strength of concrete, a low value of the surface tension and contact angle were required for PC. To have a good performance for PC, the reaction condition of 1.3 mol ratio of MA against to MPEG was suitable with KSP initiator.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.831-836
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• 2001

Little information on the cholesterol content and the fatty acid composition of avian species other than chicken is available. This study was conducted to compare the yolk cholesterol content and the fatty acid profiles of some wild birds maintained in captivity on commercial grain-based chicken diets. The concentration of cholesterol/g of yolk as well as the total yolk cholesterol per egg varied among species. Yolk cholesterol concentration, expressed as mg/g of yolk, was highest in chukar, followed by pheasant, guinea fowl and quail, while total yolk cholesterol in an egg was highest in guinea fowl, followed by pheasant, chuckar and quail. An inverse relationship between yolk cholesterol concentration and egg weight was observed among species with an exception of quail. Although major fatty acids of egg yolk were oleic acid, palmitic acid, linoleic acid and stearic acid in all birds, the composition varied among species. Chukar and quail showed higher oleic acid content than pheasant and guinea fowl, while showing lower linoleic acid. Fatty acids of chukar and guinea fowl eggs were more saturated than those of pheasant and quail. Chukar and especially quail had higher monounsaturated fatty acids (MUFA) than pheasant and guinea fowl; in quail egg 51.6% of total fatty acids were MUFA. Polyunsaturated fatty acids (PUFA), essential fatty acids (EFA) and the ratio of PUFA to saturated fatty acid (P/S ratio) were higher in pheasant and guinea fowl than in chukar and quail. Differences in fatty acid profile of triglyceride (TG) among birds were largely similar to those of total lipid. In comparison to TG, phosphatidyl choline (PC) was low in MUFA while high in saturated fatty acids (SFA), PUFA, P/S ratio and EFA. PC was most saturated in guinea fowl egg yolk, followed by chukar, quail and pheasant. PUFA, P/S ratio and EFA in PC were highest in pheasant followed by chukar, guinea fowl and quail. PE was distinguished from PC by its high contents of stearic acid, eicosapentenoic acid (EPA) and docosahexenoic acid (DHA) while low in palmitic, oleic and linoleic acids. In egg yolk of all birds MUFA was significantly lower in PE than in PC except in quail. Compared to other species, quail had a considerably higher content of MUFA in PE at the expense of SFA and PUFA.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.170-181
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• 1997

The number of modernized green houses have been increased to produce high quality and high-payoff farm products. The unit investment costs per pyeong($3.3058m^2$) for building a glass house was estimated at 449 thousand won. On the other hand, the unit prices for the PC house with iron frame and the vynil house with automatic control system were revealed 365 thousand won and 93 thousand won respectively. The main objective of the study was to identify the financial feasibility of the green house investment prevailed in rural area. At present, some farmers have selected the green house without any consideration of profitability of crops and accessiblity of their fanning practices and technology. For the soundness of green house cultivation and management, the indices of finacial efficiency for the modernized green houses were necessary. The decesion making criteria such as NPV(Net Present Value), IRR(Internal Rate of Return), B/C Ratio and Payback Period were analyzed for the individual high investment facilities considering the present farmer's technology and on-farm benefits and costs. The results of the feasibility analysis of green houses were as follows: 1. In case of 100% private burden of the investment costs, NPV revealed only positive value for the vinyl house with automatic system and IRR for the house was also estimated at more than 10% and B/C Ratio was amounted to more than 1.0. On the other hand, the other glass and PC houses showed negative NPV and unacceptable B/C ratio and IRR. 2. In case of the following terms and conditions as 50% Government subsidy, 20% loans and 30% farmers burden of the total investment cost, all the green houses showed acceptable IRR, B/C Ratio and NPV. 3. The financial feasibility of the glass house was acceptable in tomato cultivation rather than in cucumber cultivation. The payback periods of cucumber were represented as 8.9 years for glass house, 8.5 years for PC house and 4.1 years for vinyl house with automatic system respectively. In conclution, the glass and PC house cultivation of high value vegetables were only acceptable under the Goverment subsidy and loan systems from the view point of farmer's financial situations. On account of the unacceptable economic rate of return, the government subsidy and loan policy for glass house cultivation should be transfered to the vinyl and pc houses in the future.

• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.11-20
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• 2010

With the amendment to the Building Act in November of 2005 that offered incentives in terms of floor area ratio and number of stories to apartment buildings adopting the Rahmen structure to facilitate remodeling, the construction industry is paying more attention to PC structures. As connections between PC columns and beams require complex design, it is very difficult to install and remove forms. Since forms made of plywood for such connections are fabricated and installed on site, a significant amount of labor is required, and constructability is low. Furthermore, after concrete casting, the forms are removed in a state in which they cannot be recycled, which leads to a significant amount of construction waste. For this reason, a solution to address such issues needs to be studied. However, many researchers have focused only on the structural performance of PC structures in Korea and elsewhere, ignoring the need for research on the forms used in building PC structure connections. Therefore, this research aims to develop a form that can improve the productivity of PC structure connection construction, and compare it with conventional forms to highlight its contribution to gains in productivity and economic viability.