• Title/Summary/Keyword: closure operators

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Enterovirus 71 infection: An experience in Korea, 2009

  • Kim, Kyung-Hyo
    • Clinical and Experimental Pediatrics
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    • v.53 no.5
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    • pp.616-622
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    • 2010
  • Enterovirus 71 (EV71) has been recognized as a frequent cause of epidemics of hand-foot-and-mouth disease (HFMD) associated with severe neurological symptoms. In the spring of 2009, HFMD was epidemic in Korea. Severe cases with complication, including death, have been reported and it has become a public health issue. Most symptomatic EV71 infections commonly result in HFMD or herpangina. These clinical manifestations can be associated with neurologic syndromes frequently. Neurologic syndromes observed in EV71 include meningitis, meningoencephalomyelitis, poliomyelitis-like paralytic disease, Guillain-Barr$\acute{e}$ syndrome, transverse myelitis, cerebellar ataxia, opsoclonus-myoclonus syndrome, benign intracranial hypertension, and brainstem encephalitis. Examinations for EV 71 were performed from the stools, respiratory secretion or CSF of the children by realtime PCR. Gene analysis showed that most of them were caused by EV71 subgenotype C4a which was prevalent in China, 2008. Public health measures including personal and environmental hygiene, must to target daycare centers, kindergartens, and schools where highly susceptible children congregate. To prevent the spread of infection, preschools where transmission persists for more than 2 incubation periods, have been recommended for closure, and trigger criteria for voluntary closure was instituted. During closure, operators are to thoroughly clean the centers before they are allowed to reopen. In addition, parents are advised to ensure that their children adopt a high standard of personal hygiene and to keep the infected child at home until full recovery. Because the outbreaks occur in a cyclical pattern, surveillance system to predict next outbreaks and adequate public health measures to control need to be planned for future. Control of EV71 epidemics through surveillance and public health intervention needs to be maintained in Korea. Future research should focus on understanding of EV71 virulence, identification of the receptor(s) for EV71, development of antiviral agents and development of vaccine.

A study on improving the accuracy of machine learning models through the use of non-financial information in predicting the Closure of operator using electronic payment service (전자결제서비스 이용 사업자 폐업 예측에서 비재무정보 활용을 통한 머신러닝 모델의 정확도 향상에 관한 연구)

  • Hyunjeong Gong;Eugene Hwang;Sunghyuk Park
    • Journal of Intelligence and Information Systems
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    • v.29 no.3
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    • pp.361-381
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    • 2023
  • Research on corporate bankruptcy prediction has been focused on financial information. Since the company's financial information is updated quarterly, there is a problem that timeliness is insufficient in predicting the possibility of a company's business closure in real time. Evaluated companies that want to improve this need a method of judging the soundness of a company that uses information other than financial information to judge the soundness of a target company. To this end, as information technology has made it easier to collect non-financial information about companies, research has been conducted to apply additional variables and various methodologies other than financial information to predict corporate bankruptcy. It has become an important research task to determine whether it has an effect. In this study, we examined the impact of electronic payment-related information, which constitutes non-financial information, when predicting the closure of business operators using electronic payment service and examined the difference in closure prediction accuracy according to the combination of financial and non-financial information. Specifically, three research models consisting of a financial information model, a non-financial information model, and a combined model were designed, and the closure prediction accuracy was confirmed with six algorithms including the Multi Layer Perceptron (MLP) algorithm. The model combining financial and non-financial information showed the highest prediction accuracy, followed by the non-financial information model and the financial information model in order. As for the prediction accuracy of business closure by algorithm, XGBoost showed the highest prediction accuracy among the six algorithms. As a result of examining the relative importance of a total of 87 variables used to predict business closure, it was confirmed that more than 70% of the top 20 variables that had a significant impact on the prediction of business closure were non-financial information. Through this, it was confirmed that electronic payment-related information of non-financial information is an important variable in predicting business closure, and the possibility of using non-financial information as an alternative to financial information was also examined. Based on this study, the importance of collecting and utilizing non-financial information as information that can predict business closure is recognized, and a plan to utilize it for corporate decision-making is also proposed.

ON A SUBCLASS OF CERTAIN STARLIKE FUNCTIONS WITH NEGATIVE COEFFICIENTS

  • Kamali, Muhammet;Orhan, Halit
    • Bulletin of the Korean Mathematical Society
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    • v.41 no.1
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    • pp.53-71
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    • 2004
  • A certain subclass $T_{\Omega}(n,\;p,\;\lambda,\;\alpha)$ of starlike functions in the unit disk is introduced. The object of the present paper is to derive several interesting properties of functions belonging to the class $T_{\Omega}(n,\;p,\;\lambda,\;\alpha)$. Coefficient inequalities, distortion theorems and closure theorems of functions belonging to the class $T_{\Omega}(n,\;p,\;\lambda,\;\alpha)$ are determined. Also we obtain radii of convexity for the class $T_{\Omega}(n,\;p,\;\lambda,\;\alpha)$. Furthermore, integral operators and modified Hadamard products of several functions belonging to the class $T_{\Omega}(n,\;p,\;\lambda,\;\alpha)$ are studied here.

ON THE TANGENT SPACE OF A WEIGHTED HOMOGENEOUS PLANE CURVE SINGULARITY

  • Canon, Mario Moran;Sebag, Julien
    • Journal of the Korean Mathematical Society
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    • v.57 no.1
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    • pp.145-169
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    • 2020
  • Let k be a field of characteristic 0. Let ${\mathfrak{C}}=Spec(k[x,y]/{\langle}f{\rangle})$ be a weighted homogeneous plane curve singularity with tangent space ${\pi}_{\mathfrak{C}}:T_{{\mathfrak{C}}/k}{\rightarrow}{\mathfrak{C}$. In this article, we study, from a computational point of view, the Zariski closure ${\mathfrak{G}}({\mathfrak{C}})$ of the set of the 1-jets on ${\mathfrak{C}}$ which define formal solutions (in F[[t]]2 for field extensions F of k) of the equation f = 0. We produce Groebner bases of the ideal ${\mathcal{N}}_1({\mathfrak{C}})$ defining ${\mathfrak{G}}({\mathfrak{C}})$ as a reduced closed subscheme of $T_{{\mathfrak{C}}/k}$ and obtain applications in terms of logarithmic differential operators (in the plane) along ${\mathfrak{C}}$.

Some Fundamental Concepts in (2, L)-Fuzzy Topology Based on Complete Residuated Lattice-Valued Logic

  • Zeyada, Fathei M.;Zahran, A.M.;El-Baki, S.A.Abd;Mousa, A.K.
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.3
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    • pp.230-241
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    • 2010
  • In the present paper we introduce and study fundamental concepts in the framework of L-fuzzifying topology(so called(2,L)-fuzzy topology)as L-concepts where L is a complete residuated lattice. The concepts of (2,L)-derived, (2,L)-closure, (2,L)-interior, (2,L)-exterior and (2,L)-boundary operators are studied and some results on above concepts are obtained. Also, the concepts of an L-convergence of nets and an L-convergence of filters are introduced and some important results are obtained. Furthermore, we introduce and study bases and subbases in (2,L)-topology. As applications of our work the corresponding results(see[10-11]) are generalized and new consequences are obtained.

SOME CLASSES OF MULTIVALENT FUNCTIONS WITH NEGATIVE COEFFICIENTS I

  • AUOF, M.K.;DARWISH, H.E.
    • Honam Mathematical Journal
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    • v.16 no.1
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    • pp.119-135
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    • 1994
  • Let $Q_{n+p-1}(\alpha)$ denote the- dass of functions $$f(z)=z^{P}-\sum_{n=0}^\infty{a_{(p+k)}z^{p+k}$$ ($a_{p+k}{\geq}0$, $p{\in}N=\left{1,2,{\cdots}\right}$) which are analytic and p-valent in the unit disc $U=\left{z:{\mid}z:{\mid}<1\right}$ and satisfying $Re\left{\frac{D^{n+p-1}f(\approx))^{\prime}}{pz^{p-a}\right}>{\alpha},0{\leq}{\alpha}<1,n>-p,z{\in}U.$ In this paper we obtain sharp results concerning coefficient estimates, distortion theorem, closure theorems and radii of p-valent close-to- convexity, starlikeness and convexity for the class $Q_{n+p-1}$ ($\alpha$). We also obtain class preserving integral operators of the form $F(z)=\frac{c+p}{z^{c}}\int_{o}^{z}t^{c-1}f(t)dt.$ c>-p $F\left(z\right)=\frac{c+p}{z^{c}}\int_{0}^{z} t^{c-1}f\left(t \right)dt. \qquad c>-p$ for the class $Q_{n+p-1}$ ($\alpha$). Conversely when $F(z){\in}Q_{n+p-1}(\alpha)$, radius of p-valence of f(z) has been determined.

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Various Application of Distraction Osteogenesis in Cleft Lip and Palate related Deformities (구순구개열과 관련된 상악골 변형의 치료를 위한 골신장술의 다양한 적용예)

  • Yi Ho;Baek Seung-Hak;Lee Jong-Ho;Choi Jin-Young
    • Korean Journal of Cleft Lip And Palate
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    • v.8 no.1
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    • pp.11-22
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    • 2005
  • There ate anteroposterior$\cdot$vertical maxillary underdevelopment, transverse maxillary deficiency and wide cleft alveolus$\cdot$oroanual fistula among cleft lip ant palate related maxillary deformities. For treatment of these deformities, ones have used conventional treatment methods, there were often unsatisfactory results to patients and operators both. Since llizarov introduced effective technique of bone lengthening and augmentation for a variety of limb defotmities, application of distraction osteogenesis on maxillofacial area has been used to solve those disadvantages of conventional methods. Authors introduced following three cases about use of distraction osteogenesis. The first case is the application of RED(rigid external distraction) II system for the treatment of the anteroposterior$\cdot$vertical maxillary hypoplasia after several times of surgery and end of development in bilateral cleft lip and palate patient. The second case is the application of the USPD(unilateral segmental palatal distraction) for the resolution of the unilateral posterior crossbite and transverse dental arch asymmetry after alveolorraphy in growing unilateral cleft lip and palate patient. The third case is the application of transport distraction osteogenesis far closure of the wide clef alveolus and oroantral fistula in growing bilateral cleft lip and palate patient. There were satisfactory results in these cases. Particularly, in comparison with the decreases of relapse rates, the reduction of the hospitalization time and post-operative discomfort owing to minimal surgical intervention.

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Study on Preventing Copyrights Infringement through Blocking Advertisements of Illegal Copyrighted Websites (불법 저작물 사이트의 광고 차단을 통한 저작권 침해 방지 연구 - 자금 추적 기반 방식을 중심으로)

  • Shin, Myeong-Seob;Yong, Mi-Ran;Lee, Yeong-Ju
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.331-341
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    • 2020
  • Recently the government has succeeded in shutting down the Illegal Copyrighted Websites by cracking down on the operators of the websites. But this only caused 'the Balloon Effect', similar websites were created and users shifted to the new websites. 'Follow the money' is drawing attention as a way to complement the effect of policies. It tracks the commercialization scheme and fund flows of the Illegal Copyrighted Websites and blocks the supply and publication of advertisements, which are the main source of revenue. This approach aims at self-closure of Illegal websites by blocking the revenue source. In this study, we have selected and analyzed overseas cases that adopted these measures. Many countries had different policies and campaigns, but three things are common: non-punishment measures, partnership based on voluntary participation, pursuing a variety of purposes other than protecting the copyright industry. In Korea, the reason public-private Partnerships was not properly established had been caused by the difference of views between them. Advertisers and agencies need to expand their awareness that illegal advertisements can have adverse effects such as brand image damage and enormous economic losses. Also campaigns and conferences related with the policy should be held to prevent copyright infringement through mutual understanding and cooperation.

A Study on the Policy Proposal for the Revitalization of Small Libraries in the Residential Communities in Gyeonggi-do (경기도 공동주택단지 내 작은도서관 활성화를 위한 정책 제안 연구)

  • Noh, Younghee;Choi, Man-Ho;Kim, Yoon-Jeong;Chang, Rosa
    • Journal of the Korean Society for Library and Information Science
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    • v.54 no.3
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    • pp.71-95
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    • 2020
  • In Gyeonggi-do(province), where the largest number of small libraries are located in Korea, 42% of small libraries are located in apartment complexes. However, as libraries established under legal obligations are managed and operated on voluntary will, there have been numerous ongoing cases of temporary closure or permanent shut down. To revitalize small libraries in apartment complexes, it is reasonable to seek ways to revitalize them through the role of the central point of the village community in the complex. To that end, this study surveyed the current status of small libraries in Gyeonggi-do, a survey of small library operators and related persons in apartment housing complexes and similar residential communities in Gyeonggi-do and 31 cities and counties. Based on this, this study was intended to derive practical measures to revitalize the operation and preservation of small libraries in such residential communities. Four goals were set to improve community awareness of small libraries, cultivate self-operating abilities, improve laws and systems, and strengthen support for local governments. Research needs to be carried out not only for small libraries in apartment complexes in Gyeonggi-do but also for the continued development of other small private libraries.

The Effect of Perceived Loss of Financial·Market·Social Capital Based on Recurrence Intention of Failed Small Business : Focusing on the Mediating Effect of Fear of Failure and the Moderating of Entrepreneurial Self-Efficacy (폐업 소상공인의 재무적자본·시장경쟁력·사회적자본 손실지각이 재기의도에 미치는 영향 : 실패두려움의 매개효과와 창업자기효능감의 조절효과를 중심으로)

  • Cho, Young-Ryong;Park, Ju-Young
    • Korean small business review
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    • v.43 no.4
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    • pp.59-93
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    • 2021
  • This study surveyed 413 small business owners who experienced closure to see how the loss perception experienced by small business owners affects their comeback through fear of failure. The analysis results are as follows. First, the larger the received loss of financial capital, market capital, and social capital, the greater the fear of failure. Second, the greater the fear of failure, the less willingness to re-start-up, but it did not affect the willingness to work. Third, perceived loss of financial capital, market capital, and social capital grew fear of failure, which negatively affected the willingness to re-start. However, as for the willingness to work, only the perception of loss to market competitiveness strengthened the willingness to work through fear of failure. This suggests that if you think you are out of business due to market competitiveness, you are more likely to choose to get a job than to start a business. Fourth, those with higher entrepreneurial self-efficiency had less effect of perceived loss on fair of failure than those with lower entrepreneurial loss. In other words, it can be seen that a person with high entrepreneurial self-efficiency is likely to start-up. It is noteworthy that despite the tendency to fail due to market competition and lack of understanding of risks, small business operators were most aware of the loss of social capital. This is presumed to have had the greatest impact on fear of failure because small business owners try to receive funding or business revitalization support through social networks such as acquaintances and relatives. Based on the above results, this study requires sufficient market research to secure a competitive advantage when preparing for start-ups through policy practice suggestions, and suggests ways to reduce financial loss through the establishment of sophisticated business plans.