• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.723-726
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• 2008

It is not always easy to estimate the parameters in hydrologic models due to insufficient hydrologic data when hydraulic structures are designed or water resources plan are established, uncertainty analysis, therefore, are inevitably needed to examine reliability for the estimated results. With regard to this point, this study applies a Bayesian Markov Chain Monte Carlo scheme to the NWS-PC rainfall-runoff model that has been widely used, and a case study is performed in Soyang Dam watershed in Korea. The NWS-PC model is calibrated against observed daily runoff, and thirteen parameters in the model are optimized as well as posterior distributions associated with each parameter are derived. The Bayesian Markov Chain Monte Carlo shows a improved result in terms of statistical performance measures and graphical examination. The patterns of runoff can be influenced by various factors and the Bayesian approaches are capable of translating the uncertainties into parameter uncertainties. One could provide against an expected runoff event by utilizing information driven by Bayesian methods. Therefore, the rainfall-runoff analysis coupled with the uncertainty analysis can give us an insight in evaluating flood risk and dam size in a reasonable way.

• Journal of Biosystems Engineering
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• 제10권2호
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• pp.47-54
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• 1985

Performance of a screw press was investigated experimentally with soybeans of various temperatures in order to find out a proper temperature of soybean to extract the oil by the mechanical method. Crude oil extracted by the screw press was chemically analyzed to determine a level of processing the oil for the oil to be used as a fuel for a compression ignition engine. The crude oil was degummed and dried by a plant type laboratory experimental setup to decide whether the processes are effective to improve quality of the oil as a fuel. The degummed oil and the degummed and dried oil were also chemically analyzed and were compared with the crude oil and the commercially degummed and dried soybean oil. The results are as follows: 1. In extraction of soybean oil by a screw press, heating soybeans is effective to increase oil production and to decrease energy consumption of the press. A proper temperature of soybean to extract the oil by the press was determined as about $50^{\circ}C$. 2. Soybean oil production and electric energy consumption of the press are about 83 ml and 58 Wh per 1 kg of soybeans heated to about $50^{\circ}C$, respectively. 3. The quality of crude oil produced by the press is similar to that of the commercially degummed and dried oil. The crude oil does not need to be degummed or dried for use as an engine fuel.

• East Asian Economic Review
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• 제24권2호
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• pp.127-164
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• 2020

We perform an econometric assessment of the role that pharmaceutical innovation-the introduction and use of new drugs-has played in improving the health of Koreans, by investigating whether diseases for which more new drugs were launched had larger subsequent increases in longevity and smaller subsequent increases in hospitalization. Drugs launched during 1993-2012 are estimated to have increased mean age at death from all diseases by 1.71 years between 1995 and 2015 and 1.09 years between 2005 and 2015. We also estimate that new drugs increased the five-year relative survival rate from all cancers combined by 23.2 percentage points-78.5% of the total increase-between 1993-1995 and 2011-2015, and that new drugs launched during 2008-2010 reduced the number of hospital days in 2017 by 13.0 million. If the drugs launched during 2003-2012 had had no effect on other medical expenditure in 2015, the cost per life-year gained would not have exceeded 6332 USD. Therefore, even if we ignore the effect of new drugs on hospital utilization, the drugs launched during 2003-2012 were very cost-effective, overall. When reduced hospital utilization is accounted for, the evidence indicates that, in the long run, pharmaceutical innovation was cost-saving as well as life-year saving.

• Communications for Statistical Applications and Methods
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• 제23권6호
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• pp.531-541
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• 2016

Cerebral atrophy affects the brain and is a common feature of patients with mild cognitive impairment or Alzheimer's diseases. It is evaluated by the radiologist or reader based on patient's history, age and the space between the brain and the skull as indicated by magnetic resonance (MR) images. A total of 70 patients were scanned in the supine and prone positions before three radiologist assessed their atrophy level. This study examined the radiologist's assessment of the cerebral atrophy level using a graded response model of item response theory (IRT). A graded response model (GRM) is fitted to our data and then item-fit and person-fit statistics are evaluated to assess the fitted model. Our analysis found that the cerebral atrophy level is better discriminated by readers in the prone position because all item slopes were greater than 2 at this position, versus the supine position where all the slope parameters were less than 1. However, the thresholds are very similar for the first reader and are quite different for the second and third readers because the scanning position affects readers differently as the category threshold estimates vary considerably between the readers..

• Journal of Microbiology
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• 제43권5호
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• pp.383-390
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• 2005

The diversity of the denitrifying bacterial populations in Daejeon Sewage Treatment Plant was examined using a culture-dependent approach. Of the three hundred and seventy six bacterial colonies selected randomly from agar plates, thirty-nine strains that showed denitrifying activity were selected and subjected to further analysis. According to the morphological and biochemical properties, the thirty nine isolates were divided into seven groups. This grouping was supported by an unweighted pair group method, using an arithmetic mean (UPGMA) analysis with fatty acid profiles. Restriction pattern analysis of 16S rDNA with four endonucleases (AluI, BstUI, MspI and RsaI) again revealed seven distinct groups, consistent with those defined from the morphological and biochemical properties and fatty acid profiles. Through the phylogenetic analysis using the 16S rDNA partial sequences, the main denitrifying microbial populations were found to be members of the phylum, Proteobacteria; in particular, classes Gammaproteobacteria (Aeromonas, Klebsiella and Enterobacter) and Betaproteobacteria (Acidovorax, Burkholderia and Comamonas), with Firmicutes, represented by Bacillus, also comprised a major group.

• 한국식품조리과학회지
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• 제25권4호
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• pp.421-426
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• 2009

The objective of this study was to evaluate the antioxidant and physiological The objective of this study was to evaluate the antioxidant and physiological activities of organic and inorganic coffee based on flavonoid composition. Organic and inorganic coffee varieties were prepared with Brazil arabica bean and Columbia arabica bean, respectively. Color values (Lightness, redness, and yellowness), mineral contents, total phenol content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, individual flavonoids, and sensory characteristics were then measured in the espresso of each coffee bean. The pH, Brix, and color difference between organic coffee and inorgainc coffee did not correlate with the harvest method. Coffee varieties were more influential on physiological properties, and were markedly more influential than the mineral content. Total phenolics had a higher correlation with DPPH radical scavenging activity ($r^2$=0.832). Depending on the harvesting method, significant differences (p<0.05) were shown in aroma, color, and overall acceptability in sensory evaluation.

• 한국식품조리과학회지
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• 제30권6호
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• pp.757-766
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• 2014

The purpose of this study was to investigate the antioxidant effects of non-fermented (CAC) and Monascus pilosus-fermented Columbia arabica coffee (FCAC), as well as Luwak coffee (LC) beans. The results indicated that total polyphenols content (mg/g of dry basis) was highest in CAC (70.69), followed by LC (62.07), and FCAC (41.38). However, the ratio of total flavonoids/polyphenols in FCAC was the highest. In terms of electron donating ability (%, coffee mg/mL), CAC was significantly higher than LC and FCAC. Regardless of fermentation, ferric reducing antioxidant powers were similar in CAC and FCAC and lowest in LC. LC also had the highest inhibitory activity against xanthine oxidase (XO). However FAAC had the highest inhibitory activity against aldehyde oxidase (AO), with nearly three times the levels found in CAC and LC. According to the above results, FCAC had a higher ratio of flavonoids/polyphenols and iron chelating activity than CAC. FCAC also had the highest AO inhibitory activity among the three experimental coffee beans. The results suggest that further studies are required to evaluate the bioactive components of various coffee beans so as to determine the potential benefits that coffee may have on preventing oxidative stress-related conditions.

• Membrane and Water Treatment
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• 제9권2호
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• pp.123-128
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• 2018

Common aquaculture practices include the use of certain pharmaceuticals such as antibiotics in avoiding diseases and promoting a healthier growth of the culture. The aim of this study is to monitor and assess the influence of different low oxytetracycline concentrations on the transformation of nitrogen compounds under aeration condition in a lab-scale recirculating aquaculture system (RAS). Over $1mg\;L^{-1}$ dose of oxytetracycline to aquaculture had induced ammonia($NH_4-N$), nitrate($NO_3-N$), soluble COD accumulation in RAS. In addition, nitrous oxide ($N_2O$) emission from RAS was significantly reduced during the oxytetracycline dose periods. After ceasing the dose of oxytetracycline, ammonia oxidation and nitrous oxide re-emission were observed. This observation indicated that low concentrations of oxytetracycline could affect the nitrogen species in RAS. Also, the emission mechanisms of $N_2O$ may not be only dependent on nitrification process but also dependent on denitrification process in our RAS system.

• Structural Engineering and Mechanics
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• 제73권5호
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• pp.599-612
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• 2020

A combination of a gravity wall and an anchor beam is widely used to support the high soil deposit on rock mass. In this study, two groups of shaking table test were performed to investigate the responses of such combined retaining structure, where the rock masses were shaped with a flat surface and a curved surface, respectively. Meanwhile, the dynamic numerical analysis was carried out for a comparison or an extensive study. The results were studied and compared between the combined retaining structures with different shaped rock masses with regard to the acceleration response, the earth pressure response, and the axial anchor force. The acceleration response is not significantly influenced by the surface shape of rock mass. The earth pressure response on the combined retaining structure with a flat rock surface is more intensive than the one with a curved rock surface. The anchor force is significantly enlarged by seismic excitation with a main earthquake-induced increment at the first intensive pulse of Wenchuan motion. The value of anchor force in the combined retaining structure with a flat rock surface is generally larger than the one with a curved rock surface. Generally, the combined retaining structure with a curved rock surface presents a better seismic performance.

• 영어영문학
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• 제64권2호
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• pp.151-170
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• 2018

This paper examines the relationship and ideas of Hannah Arendt and Philip Roth including how they met, their correspondence and intellectual parallels, particularly in their shared criticism of Jewish ideals and culture in Europe and North America. It analyzes similarities in their careers and texts, especially between Eichmann in Jerusalem and Operation Shylock, as well as The Ghost Writer, while measuring their reception as social commentators and writers. Kafka was an important figure for both writers, Arendt's earliest writing engaged with the significance of Kafka in understanding and criticizing twentieth century political and cultural values in Europe. For Roth, Kafka offered a similar critique of moral principles he found corroded in North American Jewish life. Arendt connected with other writers, notably Isak Dinesen, W. H. Auden, Randall Jarrell and William Styron who further linked the two: he knew both Arendt and Roth and cited, incorrectly, a work by Arendt as the source for the key incident in his 1979 novel Sophie's Choice. He claimed it was Eichmann in Jerusalem; it was Arendt's The Origins of Totalitarianism. Arendt's reaction to Roth's fiction, however, remains a mystery: she died in 1975, before Roth began to seriously and consistently engage with Holocaust issues in works like The Ghost Writer (1979) and Operation Shylock (1993). Yet even in death they are joined. Their graves are only steps apart at the Bard College Cemetery in Annandale-on-Hudson, New York.