• Title/Summary/Keyword: Addition-Elimination

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Genetic Diversity of Plasmodium vivax Causing Epidemic Malaria in the Republic of Korea

  • Bahk, Young Yil;Kim, Jeonga;Ahn, Seong Kyu;Na, Byoung-Kuk;Chai, Jong-Yil;Kim, Tong-Soo
    • Parasites, Hosts and Diseases
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    • v.56 no.6
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    • pp.545-552
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    • 2018
  • Plasmodium vivax is more challenging to control and eliminate than P. falciparum due to its more asymptomatic infections with low parasite densities making diagnosis more difficult, in addition to its unique biological characteristics. The potential re-introduction of incidence cases, either through borders or via human migrations, is another major hurdle to sustained control and elimination. The Republic of Korea has experienced re-emergence of vivax malaria in 1993 but is one of the 32 malaria-eliminating countries to-date. Despite achieving successful nationwide control and elimination of vivax malaria, the evolutionary characteristics of vivax malaria isolates in the Republic of Korea have not been fully understood. In this review, we present an overview of the genetic variability of such isolates to increase understanding of the epidemiology, diversity, and dynamics of vivax populations in the Republic of Korea.

A Study on Measurement and Elimination Methods of Dissolved Nitrogen in Kerosene (케로신 내 용존질소 측정 및 제거 방법 연구)

  • Lee, Wongu;Kim, Seong Lyong;Ahn, Kyubok
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.6
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    • pp.142-148
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    • 2018
  • To improve the performance of a launch vehicle, kerosene, a launch vehicle fuel, undergoes a densification process. Liquid nitrogen injection cooling is an effective densification method which has a simple system and is inexpensive. During the cooling process, however, nitrogen may dissolve in the kerosene, possibly resulting in changes to fuel properties. Therefore, it is essential to measure and eliminate the amount of dissolved nitrogen in the kerosene. In this study, the vacuum extraction principle is introduced to measure the content of dissolved nitrogen in the kerosene. In addition, the experimental results, which used a designed/manufactured nitrogen sampling device, are described. From the results, the validity of the nitrogen sampling device and the dissolved nitrogen measurement/elimination methods was demonstrated.

Prediction on the Ratio of Added Value in Industry Using Forecasting Combination based on Machine Learning Method (머신러닝 기법 기반의 예측조합 방법을 활용한 산업 부가가치율 예측 연구)

  • Kim, Jeong-Woo
    • The Journal of the Korea Contents Association
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    • v.20 no.12
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    • pp.49-57
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    • 2020
  • This study predicts the ratio of added value, which represents the competitiveness of export industries in South Korea, using various machine learning techniques. To enhance the accuracy and stability of prediction, forecast combination technique was applied to predicted values of machine learning techniques. In particular, this study improved the efficiency of the prediction process by selecting key variables out of many variables using recursive feature elimination method and applying them to machine learning techniques. As a result, it was found that the predicted value by the forecast combination method was closer to the actual value than the predicted values of the machine learning techniques. In addition, the forecast combination method showed stable prediction results unlike volatile predicted values by machine learning techniques.

Understand the Molecular Orbital Theory on the Hydrolytic Reactivity of Herbicide Flumioxazine (제초제 Flumioxazine의 가수분해 반응성에 관한 분자 궤도론적 이해)

  • Sung, Nack-Do;Jung, Hoon-Sung
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.265-271
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    • 2004
  • Hydrolytic reactivities of N-phenylphthalimid herbicide flumioxazine (S) were disccused using molecular orbital (MO) theoretical method. It is revealed that below pH 5.0, the protonation $(SH^+)$ to carbonyl oxygens atom $(O_{21})$ of 1,2-dicarboximino group by general acid catalysis $(k_A)$ with hydronium ion $(H_3O^+)$ proceeds via charge controled reaction. Whereas, the specific base catalysis $(k_{OH})$ with hydroxide anion via orbital controled reaction occurs above pH 8.0. We may concluded that in the range of pH $5.0\sim8.0$, the hydrolysis proceeds through nucleophilic addition elimination $(Ad_{N-E})$ reaction, these two reactions occur competitively.

The Analysis of the Maison Margiela's Design Code -Focusing on the Checklist Method- (메종 마르지엘라의 디자인 코드 분석 -체크리스트법을 중심으로-)

  • Mok, So-Ri;Cho, Jean-Suk
    • Journal of Fashion Business
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    • v.19 no.4
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    • pp.135-152
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    • 2015
  • The purpose of this study is to explore the role of deconstruction and creative destruction in Maison Margiela’s fashion design code, which has opened the door to a new wave of innovative design since 1988. Using a combination of theoretical analysis, precedent research, and a review of existing literature, five years of Maison Margiela's works (2010-2014) were evaluated. The analysis shows that Maison Margiela’s Design Code consists of the following key elements: Addition, Extension, Asymmetry, Elimination, Deconstruction, Complanation, and Inversion. Addition refers to act of attaching additional pieces of fabric or clothing on the existing piece. Extension refers to the act of extending the design elements, such as their position or features. Asymmetry means the irregular positioning of left-to right and front-to-back length and features. Deconstruction could be seen in intentionally frayed sleeves, open seams, and tears in the cloth. The element of Elimination was evident in the removal of key pieces of clothing such as a coat, pants, blouse, and a jacket. Complanation refers to the reversion to a two dimensional contemplation of the human form rather than the more obvious 3-dimensional form. Finally, Inversion was used by displaying an inner layer of clothing on the outside or exposing seams or zippers in a way that people are not accustomed to seeing. It also meant that the order of wearing clothes was sometimes inverted, so external layers would be worn within clothing that are traditionally underneath. Maison Margiela’s creations represented a break

Nonuniform Encoding and Hybrid Decoding Schemes for Equal Error Protection of Rateless Codes

  • Lim, Hyung Taek;Joo, Eon Kyeong
    • ETRI Journal
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    • v.34 no.5
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    • pp.719-726
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    • 2012
  • Messages are generally selected with the same probability in the encoding scheme of rateless codes for equal error protection. In addition, a belief propagation (BP) decoding scheme is generally used because of the low computational complexity. However, the probability of recovering a new message by BP decoding is reduced if both the recovered and unrecovered messages are selected uniformly. Thus, more codeword symbols than expected are required for the perfect recovery of message symbols. Therefore, a new encoding scheme with a nonuniform selection of messages is proposed in this paper. In addition, a BP-Gaussian elimination hybrid decoding scheme that complements the drawback of the BP decoding scheme is proposed. The performances of the proposed schemes are analyzed and compared with those of the conventional schemes.

Effect of MoO3 Addition and Their Frequency Characteristics in Nb+5 doped Semiconductive BaTiO3 Ceramics (Nb+5첨가된 반도성 BaTiO3세라믹스에서 MoO3의 영향과 주파수 특성)

  • 윤상옥;정형진;윤기현
    • Journal of the Korean Ceramic Society
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    • v.24 no.1
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    • pp.63-69
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    • 1987
  • Effect of MoO3 additiion on the semiconductive BaTiO3 ceramics doped with 0.2 mole% Nb2O5 and their frequency characteristics have been investigated on the view of intergranular barrier layer model through the observation of changes in their electrical properties. The resistivity increases with the increase of MoO3 addition, but the capacitance, the frequency dependence of capacitance and the effect of positive temperature coefficient of resistivity (PTCR) decrease. It is explained by the possible increase in the thickness of potential barrier due to the formation of insulating layer and thus decrease in the degree of energy band bending. Both the PTCR effect and resistivity decrease with the increase of frequency due to the possible elimination of barrier layer at the grain boundary.

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Effect of S.E.C Mixing on the Properties of Concrete (S.E.C 방식에 의한 콘크리트의 혼합효과에 관한 연구)

  • 김기형;박원태;최재진
    • Journal of the Korean Society of Safety
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    • v.12 no.2
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    • pp.133-139
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    • 1997
  • Conventional concrete mixing method is to put all of the materials simultaneously into a mixer and mix for a required time. However, recently concrete researchers have reported that mixing sequence iufluences the properties of concrete. This study discusses the influence of mixing sequence and partitioning addition of mixing water. Concrete, by method of partitioning addition of mixing water, was found to have substantially stronger strength than conventional concrete with the same water-cement ratio. This means that a higher strength concrete could be obtained by using “Sand Enveloped with Cement”(S.E.C) mixing technique. Both a high bond strength between cement paste and aggregate, and elimination of bleeding both contribute to improving the strength of S. E. C concrete.

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Sodium Dependent Taurine Transport into the Choroid Plexus, the Blood-Cerebrospinal Fluid Barrier

  • Chung, Suk-Jae;Ramanathan, Vikram;Brett, Claire M.;Giacomini, Kathleen M.
    • Journal of Pharmaceutical Investigation
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    • v.25 no.3
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    • pp.7-20
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    • 1995
  • Taurine, a ${\beta}-amino$ acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine dose not cross the blood-brain barrier, we examined whether the choroid plexus, the blood-cerebrospinal fluid (CSF) barrier, plays a role in taurine transport in the central nervous system. The uptake of $[^3H]-taurine$ into ATP depleted choroid plexus from rabbit was substantially greater in the presence of an inwardly directed $Na^+$ gradient taurine accumulation was negligible. A transient in side-negative potential gradient enhanced the $Na^+-driven$ uptake of taurine into the tissue slices, suggesting that the transport process is electrogenic, $Na^+-driven$ taurine uptake was saturable with an estimated $V_{max}$ of $111\;{\pm}\;20.2\;nmole/g/15\;min$ and a $K_M\;of\;99.8{\pm}29.9\;{\mu}M$. The estimated coupling ratio of $Na^+$ and taurine was $1.80\;{\pm}\;0.122.$ $Na^+-dependent$ taurine uptake was significantly inhibited by ${\beta}-amino$ acids, but not by ${\alpha}-amino$ acids, indicating that the transporter is selective for ${\beta}-amino$ acids. Since it is known that the physiological concentration of taurine in the CSF is lower than that in the plasma, the active transport system we characterized may face the brush border (i.e., CSF facing) side of the choroid plexus and actively transport taurine out of the CSF. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to determine whether elimination kinetics of taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for upto 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005) indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e. g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of taurine was reduced (p<0.0l), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment. Collectively, our results demonstrate that taurine is transported in the choroid plexus via a $Na^+-dependent,saturable$ and apparently ${\beta}-amino$ acid selective mechanism. This process may be functionally relevant to taurine homeostasis in the brain.

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A Regression Analysis of Factors Affecting Dropout of College Students (대학생의 중도탈락에 영향을 미치는 요인 다중회귀분석)

  • Hwang, Seung-Yeon;Shin, Dong-Jin;Oh, Jae-Kon;Lee, Yong-Soo;Kim, Jeong-Joon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.4
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    • pp.187-193
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    • 2020
  • In this study, we wanted to analyze the factors at the national university level that affect college students ' elimination. In addition, national universities, private universities, universities in Seoul and universities outside of Seoul were divided into more college-specific characteristics. Except for leave of absence and departure from school, it was defined as a middle school dropout among changes of students. The data were used for analysis by receiving raw data from "University Alerts," which are operated by the Ministry of Education and the Korean Council for Educational Universities. At the university notification, 222 universities out of the schools classified as "Universities" were utilized for final analysis, and jobs, credits, scholarships, tuition fees, students, independent students, and full-time teachers were secured through multiple education. Overall, the higher the average graduate level and employee-rate the lower the rate of elimination from the middle of college students, the analysis showed. Second, the higher the average tuition fees at private universities, the more negatively affects the rate of elimination of university students. Third, higher tuition fees at universities outside the Seoul metropolitan area have a negative impact on the rate of elimination of students.