• Title/Summary/Keyword: IRA

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The Impacts of Climate Variability on Household Consumption: Evidence Based on Village Weather Data in Indonesia

  • Pratiwi Ira Eka;Bokyeong Park
    • East Asian Economic Review
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    • v.27 no.4
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    • pp.273-301
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    • 2023
  • This study investigates the impacts of long-term climate variability on household consumption in Indonesia, a country highly vulnerable to climate change. The analysis combines household survey data from nearly 5,998 families with satellite-derived weather data from NASA POWER spanning 30 years. We use the long-term variability in temperature and precipitation as a proxy for climate change. This study examines the impact of climate change which proceeds over the long term, unlike previous studies concerning one-off or short-term climate events. In addition, using satellite data enhances the accuracy of households' exposure to climate variability. The analysis finds that households in a village with higher temperature and precipitation variability significantly consume less food. This implies that households more exposed to climate change are at higher risk of malnutrition in developing countries. This study has a limitation that it cannot rule out the potential endogeneity of choosing a climate-vulnerable residential location due to economic poorness.

Purification and Characterization of Collagenase Produced by Staphylococcus aureus JJ-11 Isolated from the Human Skin (피부에서 분리한 Staphylococcus aureus JJ-11이 생산하는 collagenase의 정제 및 특성)

  • Lee Jin-Kyoung;Kim Hae-Nam;Kang Ho-Young;Jun Hong-Ki
    • Journal of Life Science
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    • v.16 no.2 s.75
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    • pp.245-252
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    • 2006
  • A bacterial strain, identified as Staphylococcus aureus JJ-11, producing collagenase was isolated out of 40 persons having skin troubles. S. aureus JJ-11 produced collagenase optimally in the media containing 1.5%(w/v) gelatin, 1%(w/v) yeast extract, 0.4%(w/v) $K_2HPO_4$, 0.005%(w/v) $NiSO_4{\cdot}6H_2O$ at $37^{\circ}C$ for 18 hrs. The collagenase produced by Staphylococcus aureus JJ-11 was purified at 6.66-folds purity through application of chromatography with Amberlite IRA-900 and Sephacryl S-300 HR columns. The molecular weight of the partially purified enzyme was estimated to be 62 kDa by SDS-PAGE. The protein exhibited optimum enzymatic activity at pH 7.0, and showed a stable activity at pH 4-8. The optimum temperature for collagenase was at $37^{\circ}C$, and activity was maintained upto $40^{\circ}C$. The enzyme activity was slightly elevated in the presence of divalents such as, $Fe^{2+},\;Co^{2+}\;and\;Ba^{2+}$ However, the activity was inhibited in the presence of $Sr^{2+}\;or\;Hg^{2+}$. The inhibition of activity by O-phenanthroline and EDTA suggested that the enzyme may contain metal which is required for activity. The enzyme showed the highest activity when insoluble collagen (type I) was, used as a substrate.

Nitrate Removal in Rural Groundwater Using Ion Exchange Resin (이온교환수지를 이용한 농 ${\cdot}$ 어촌 지하수중의 질산이온 제거)

  • Kwun, Soon-Kuk;Yu, Myong-Jin;Jung, Tae-Myung;Kim, Min-Seok
    • Korean Journal of Environmental Agriculture
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    • v.16 no.2
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    • pp.193-198
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    • 1997
  • The purpose of this study was to find out a suitable resin to remove $NO_3-N$ from groundwater. Four different commercial resins differentiated by type, porosity and nitrate selectivity were used to compare the performance of nitrate removal. Gel type, Type 2 anion exchange resin was preferable when anion concentration of raw water was low. But efficiency of this resin decreased as flow rate increased. However, macroporous type resins were not affected by increasing flow rate. Macroporous resins were preferable when anion concentrations in raw water were high and high flow rate was proposed. And the general type resin showed better efficiency when sulfate concentrations were low. However the nitrate selective resin had better efficiency in treating raw water of high sulfate concentration. From the results, it may be drawn that nitrate selective resins are preferable to general type when a sulfate concentration in groundwater is over 50mg/l.

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Purification and Characterization of Bacillus subtilis JS-17 Collagenase. (Bacillus subtilis JS-17이 생산하는 Collagenase의 정제 및 특성)

  • Lim Kyoung-Suk;Son Shung-Hui;Kang Ho Young;Jun Hong-Ki
    • Journal of Life Science
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    • v.15 no.4 s.71
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    • pp.657-663
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    • 2005
  • Collagenases are generally defined as enzymes that are capable of degrading the polypeptide backbone of native collagen under conditions that do not denature the protein. An extracellular collagenase-producing bacterial strain was isolated from kimchi and identified to be Bacillus subtilis JS-17 through morphological, cultural, biochemical characteristics and 16S rDNA sequence analysis. Optimum culture condition of Bacillus subtilis JS-17 for the production of collagenase was $1.5\%$ fructose, $1\%$ yeast extract, $0.5\%\;K_2HPO_4,\;0.4\%\;KH_2PO_4,\;0.01\%\;MgSO_4\cdot7H_2O,\;0.01\%\; MnSO_4\cdot4H_2O,\;,0.1\%$ citrate and $0.1\%\;CaCl_2$. The production of collagenase was optimal at $30^{\circ}C$ for 72 hr. A collagenase was isolated from the culture filtrate of Bacillus subtilis JS-17. The enzyme was purified using Amberlite IRA-900 column chromatography, Sephacryl S-300 HR column chromatography and DEAE-Sephadex A-50 column chromatography The purified collagenase has an specific activity 192.1 units/mg. The molecular weight of the purified enzyme was estimated to be 28 kDa by SDS-PACE. The purified collagenase has $100\%$ activity up to $55^{\circ}C$.

A Delphi Study to Validate the Patient-Centered Doctor's Competency Framework in Korea (한국의 환자 중심 의사 역량 프레임 타당화를 위한 델파이 연구 )

  • Sunju Im;Young-Jon Kim;Chanwoong Kim;Geon-Ho Lee;Sun-Woo Lee;Woo-Taek Jeon;Hanna Jung;Sojung Yune
    • Korean Medical Education Review
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    • v.25 no.2
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    • pp.139-158
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    • 2023
  • Defining a competent doctor is important for educating and training doctors. However, competency frameworks have rarely been validated during the process of their development in Korea. The purpose of this study was to validate the patient-centered doctor's competency framework, which had been developed by our expert working group (EWG). Two rounds of Delphi questionnaire surveys were conducted among a panel of experts on medicine and medical education. The panel members were provided with six core competencies, 17 sub-competencies, and 53 enabling competencies, and were asked to rate the importance of these competencies on a 5-point Likert scale. Between April and July 2021, a total of 28 experts completed both rounds. The data of the Delphi study were analyzed for the mean, standard deviation, median, inter-rater agreement (IRA), and content validity ratio (CVR). A CVR >0.36 and IRA ≥0.75 were deemed to indicate validity and agreement. This study found that five enabling competencies were not valid, and agreement was not reached for three sub-competencies and two enabling competencies. In consideration of CVR and the individual opinions of panel members at each session, the final competencies were extracted through consensus meetings of the EWG. The competencies were modified into six core competencies, 16 sub-competencies, and 47 enabling competencies. This study is meaningful in that it proposes patient-centered doctor's competencies enabling the development of residents' milestone competencies, an assessment system, and educational programs.

Study on Shift of Innovation and Manufacturing Hubs to the United States (혁신 및 제조 허브의 미국으로 이동에 관한 연구)

  • Seo, Daesung
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.2
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    • pp.553-560
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    • 2023
  • The study is about domestic industries following the migration of hubs (innovation, manufacturing) to other countries and the hub-oriented US industries (batteries, semiconductors, electric vehicles). Additionally, the ongoing trade tensions between the United States and China may have also played a role in companies moving their operations to the United States. The result of such a move could potentially include job creation in the United States, as well as increased investment in the U.S. manufacturing sector. However, it is also possible that there could be negative consequences, such as higher prices for consumers or disruptions to supply chains during the relocation process. However, such IRA, Chips Act scenario would likely also have negative consequences (Inflation in the home country) for the countries whose industries moved to the US, as they would lose jobs, investment, and possibly face economic difficulties as a result. As the result of the empirical analysis of the export scale of Korea and the United States, changes in the movement of global supply hubs are related to factors such as geopolitical price increases and consumption declines. In order to respond to these changes, this paper emphasizes the need to prevent the result of de-advantage by moving the production area of the scale.

Wideband RF Radiation from a Nonlinear Transmission Line with a Pre-magnetized Ferromagnetic Core

  • Ahn, J.-W.;Karelin, S.Y.;Krasovitsky, V.B.;Kwon, H.-O.;Magda, I.I.;Mukhin, V.S.;Melezhik, O.G.;Sinitsin, V.G.
    • Journal of Magnetics
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    • v.21 no.3
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    • pp.450-459
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    • 2016
  • Experimental results and data of numerical simulations are presented, concerning generation of wideband radio frequency (RF) oscillations in a nonlinear transmission line (NLTL) which contains a pre-magnetized core of ferrite material. Emphasis is made on the means for extracting the RF signal from the line, in order to radiate it into free space. Antennas of two types that can be used for the purpose are considered, both featuring a coaxial design. This permits availing of the principal advantages of coaxial systems, such as operation in the mode of a traveling TEM wave; wide range of the transmitted frequencies, and a reasonably simple design. The antennas studied, specifically a disc-cone dipole (DCD) and an impulse reflector antenna ('Half-IRA', or HIRA type) differ significantly in effective width of the radiated spectrum and in spatial characteristics of the radiated field in far region.

Speciation of Cr(III)/Cr(VI) in Tannery Waste Waters by Using Ion-Exchange Resins

  • Kartal, S.;Tokalloglu, S.;Ozkan, B.
    • Bulletin of the Korean Chemical Society
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    • v.27 no.5
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    • pp.694-698
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    • 2006
  • A method has been described for the chemical speciation, preconcentration and determination of Cr(III) and Cr(VI) species in filtered tannery waste waters by flame atomic absorption spectrometry using ion-exchange resins. Amberlite IR-120($H^+$) strongly acidic cation exchanger and Amberlite IRA-410($CI ^-$) strongly basic anion exchanger resins were used for the separation and preconcentration of Cr(III) and Cr(VI) species, respectively. Optimum condition for preconcentration and speciation was obtained by testing pH of sample and eluent, flow rates of sample and eluent, amount of resins, volume of sample and eluents, and effect of foreign ions. The recommended method has been successfully applied for the preconcentration and determination of chromium species in the dissolved phase of waste water samples collected from a tannery waste water treatment plant in Kayseri, Turkey. The detection limits achieved were 0.73 $\mu$g/L for Cr(III) and 0.81 $\mu$g/L for Cr(VI). Recovery studies showed 99% for Cr(III) and 98% for Cr(VI), for samples spiked with single species.

Ensuring Sound Numerical Simulation of Hybrid Automata

  • Hur, Yerang;Sim, Jae-Hwan;Kim, Je-Sung;Chai, Jin-Young
    • Journal of Computing Science and Engineering
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    • v.3 no.2
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    • pp.73-87
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    • 2009
  • A hybrid system is a dynamical system in which states can be changed continuously and discretely. Simulation based on numerical methods is the widely used technique for analyzing complicated hybrid systems. Numerical simulation of hybrid systems, however, is subject to two types of numerical errors: truncation error and round-off error. The effect of such errors can make an impossible transition step to become possible during simulation, and thus, to generate a simulation behavior that is not allowed by the model. The possibility of an incorrect simulation behavior reduces con.dence in simulation-based analysis since it is impossible to know whether a particular simulation trace is allowed by the model or not. To address this problem, we define the notion of Instrumented Hybrid Automata (IHA), which considers the effect of accumulated numerical errors on discrete transition steps. We then show how to convert Hybrid Automata (HA) to IRA and prove that every simulation behavior of IHA preserves the discrete transition steps of some behavior in HA; that is, simulation of IHA is sound with respect to HA.

Public Perception on Transparency and Trust in Government Information Released During the COVID-19 Pandemic

  • Pramiyanti, Alila;Mayangsari, Ira Dwi;Nuraeni, Reni;Firdaus, Yasinta Darin
    • Asian Journal for Public Opinion Research
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    • v.8 no.3
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    • pp.351-376
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    • 2020
  • A low level of transparency and trust in the release of government information during the COVID-19 pandemic could decrease the chance of success in handling the coronavirus outbreak. This worldwide pandemic has damaged not only human health but also created an economic and social crisis. Indonesia is no exception. Unfortunately, an analysis of a mixed-method survey of 500 participants found that public perception of transparency in the government's release of COVID-19 information is still at a low level. This perceived low level of transparency generates minimum trust in the information. Only 8% of participants trust the government's information regarding the virus. Even though the Indonesian government launched an official website, www.covid19.go.id, which is intended as a primary source of valid information about COVID-19 in Indonesia, most survey participants had never used the website. However, contrary to the low levels of perceived transparency and trust, most participants said that the messages from the government are clear and easy to understand. This contradiction resulted from skepticism toward the government. Therefore, this research presents a better understanding of how the level of transparency and trust is also related to the level of skepticism of the government.