PLP 배관 피복 손상부 탐측 정확도 향상 기술 개발

성유찬(Yuchan Sung),손기영(Kiyoung Son),성원경(Wonkyung Sung),전민수(Minsu Jeon) 한국가스학회 2020 한국가스학회 학술대회논문집 Vol.2020 No.10

The Blastomere of the 2-Cell Stage Parthenogenetic Porcine Embryo with High Lipid Content Tends to Contribute to the Embryonic Part

Kiyoung Kim,Sang Kyu Park,Sangho Roh 한국동물생명공학회(구 한국동물번식학회) 2009 발생공학 국제심포지엄 및 학술대회 Vol.2009 No.1

The Cloning and Comparative Analysis of Sus scrofa domesticus GFAP Promoter

Kiyoung Eun,Seon-ung Hwang,So-Young Chang,Hye-Min Jeon,Sang Hwan Hyun,Hyunggee Kim 한국동물생명공학회(구 한국동물번식학회) 2014 Reproductive & Developmental Biology(Supplement) Vol.38 No.2s

Glial fibrillary acidic protein (GFAP) is a class-Ⅲ intermediate filament protein specifically expressed in astrocyte of central nerve system (CNS). Studies have demonstrated that approximately 2.2 kilo-base pairs of the human and mouse GFAP promoter region are sufficient to directly regulate GFAP protein or transgene expression in astrocytes and it has been used in numerous studies dealing with the nerve system development, CNS injury-induced process, and disease models. Based on the notion that a pig displays greater taxonomic resemblance to human than a rodent, here we sought to validate a GFAP promoter sequence of a pig as a better representative of that of human. We compared the promoter, mRNA and protein sequences of human, mouse, and swine GFAP and observed that pig and human GFAP show the greatest amount of sequence resemblance. This suggests that the regulatory mechanism underlying swine GFAP expression is more similar to that of human GFAP. A 5.2kb DNA fragment of miniature swine GFAP promoter was isolated from a genomic DNA of miniature pig, Sus scrofa domesticus. In order to validate the key regulatory element of swine GFAP expression, the isolated DNA fragment was further divided into three segments. These partial and full GFAP sequences were then inserted into luciferase reporter systems and their activities were measured by GFAP inducer treatment. The increased expression of swine GFAP-luciferase transgenes was observed upon the treatment of inducer and this suggests that the swine GFAP promoter can be used to induce the expression of a target gene specifically in swine astrocytes. Furthermore, the promoter may be applied to carry out various scientific procedures such the investigation of physiological mechanism underlying gliosis or the generation of CNS disease model.

Real Activity Management in the Presence of Labor Unions : An Empirical Study Using Firm Level Union Data

Kiyoung Chang,Young Sang Kim,Ying Li 한국재무학회 2018 한국재무학회 학술대회 Vol.2018 No.05

In the presence of labor unions, management has incentives to lower earnings to prevent labor unions from extracting rents (“manipulation hypothesis”) or to boost earnings through overproduction to lower costs of unit production or reducing discretionary R&D expenditures to mitigate employees’ perception of unemployment risk and reduce cost to attract and retain employees (“forced cooperation hypothesis”). Strong union affects manager’s decision in a way that firms end up getting lower abnormal production costs and lower abnormal R&D expenditures. We test these two hypotheses through the lens of real activity management because of labor unions’ particular interest directly linked in real activities. Consistent with the forced cooperation hypothesis, we find that the power of labor unions is positively associated with real activity management, especially through the overproduction channel. The extent of upward real activity varies with union power with a magnitude that is both statistically and economically significant. The positive relation between union power and real activity is stronger when the cost of attracting and retaining employees is high, and when labor unions are valued for job security purpose. In addition, the result is consistent when states’ unemployment insurance benefits suffer negative shocks, when states adopt the “right-to-work” laws, and when firms switch from unionized to nonunionized.

Genome-wide bimolecular fluorescence complementation analysis of SUMO interactome in yeast

Sung, Min-Kyung,Lim, Gyubum,Yi, Dae-Gwan,Chang, Yeon Ji,Yang, Eun Bin,Lee, KiYoung,Huh, Won-Ki Cold Spring Harbor Laboratory Press 2013 Genome research Vol.23 No.4

<P>The definition of protein–protein interactions (PPIs) in the natural cellular context is essential for properly understanding various biological processes. So far, however, most large-scale PPI analyses have not been performed in the natural cellular context. Here, we describe the construction of a <I>Saccharomyces cerevisiae</I> fusion library in which each endogenous gene is C-terminally tagged with the N-terminal fragment of Venus (VN) for a genome-wide bimolecular fluorescence complementation assay, a powerful technique for identifying PPIs in living cells. We illustrate the utility of the VN fusion library by systematically analyzing the interactome of the small ubiquitin-related modifier (SUMO) and provide previously unavailable information on the subcellular localization, types, and protease dependence of SUMO interactions. Our data set is highly complementary to the existing data sets and represents a useful resource for expanding the understanding of the physiological roles of SUMO. In addition, the VN fusion library provides a useful research tool that makes it feasible to systematically analyze PPIs in the natural cellular context.</P>

Determinants of Target Selection and Acquirer Returns : Evidence from Cross-Border Acquisitions

Sung C. Bae,Kiyoung Chang,Doseong Kim 한국재무학회 2010 한국재무학회 학술대회 Vol.2010 No.05

We examine cross-border acquisitions of private and public targets by U.S. firms by employing self selection models. We are particularly interested in the roles of country-level liquidity and transparency in cross-border acquisitions. Our results show that a typical acquisition deal of a private target is smaller in size, uses cash less frequently for payment, and involves more hightech firms than that of a public target. Most importantly, we find that acquiring firms are more likely to buy private targets in lower-transparency countries, but the level of country liquidity has little effect on the target selection. Furthermore, after accounting for the endogeneity bias associated with target selection, country liquidity is shown to be no longer a key determinant of acquirer returns in cross-border acquisitions. Our results are robust to alternative specifications of dependent variables and self selection models.

Effect of Kinetin on In Vitro Development of Parthenogenetic Porcine Oocytes Exposed to Demecolcine Prior to Activation

Kiyoung Kim,노상호,Sang Kyu Park 사단법인 한국동물생명공학회 2009 한국동물생명공학회지 Vol.24 No.2

This study was designed to investigate the effect of kinetin on in vitro development of parthenogenetic porcine oocytes exposed to demecolcine prior to activation. In vitro matured metaphase II stage oocytes were incubated in 0 or 2 μg/ml demecolcine supplemented defined culture medium for 3 h and the oocytes were activated electrically. The parthenogenetic porcine embryos were then cultured in 0 or 200 μM kinetin supplemented defined culture medium for 7 days. Regardless of demecolcine treatment, kinetin supplementation increased blastocyst rates significantly (7.0% versus 12.1% and 4.9% versus 8.5%; Control versus Kinetin and Demecolcine versus Kinetin+Demecolcine, respectively, p<0.05). Demecolcine treatment before activation tended to decrease blastocyst rates regardless of kinetin supplementation although it is not statistically significant. Total cell numbers in the blastocysts also tended to be elevated in embryos when supplemented with kinetin, however only the result between Kinetin and Demecolcine groups is statistically significant (37.6±7.2 versus 28.1±9.5, respectively, p<0.05). In conclusion, the present report shows that kinetin enhances developmental competence of parthenogenetic porcine embryo regardless of demecolcine pre-treatment before parthenogenetic activation when they were developed in defined culture condition.

Influence Maximization Based on Minimum Redundancy Feature Selection in Pocket Switched Networks

Kiyoung Jang,Junyeop Lee,YoungOk Kwon,Byung Cho Kim,Dongwon Lee,Wonseok Oh,Sung-Bong Yang 한국정보기술학회 2016 한국정보기술학회논문지 Vol.14 No.8

It is very crucial for viral marketing to determine a handful of influential users who can disseminate the product information to the users in a network. Influence maximization is a problem of finding k users to maximize the influence to all users in networks. In Pocket Switched Networks, all users do not have information about the entire network topology. Thus, it is essential to predict the future contact opportunities for forwarding messages by analyzing the node behaviors. In this paper, we propose an influence maximization scheme based on contact frequency of the users in the network. In the scheme, we obtain the contact frequency among the users in a regular time interval during the warm-up period. At the end of the warm-up period, the main server performs the feature selection process with the contact frequency. The minimum redundancy feature selection process yields the most important features, indicating the most influential users. Finally, the server selects promising users as the influential users with the feature selection. We show that the simulation results for the diffusion time performance of the proposed scheme. The proposed scheme shows 8.5% and 12.9% more improved performance than the random and set-cover scheme.

Comparison of Focal and Conventional Verteporfin Photodynamic Therapy for Chronic Central Serous Chorioretinopathy

Sung Rae Noh,Min Seok Kang,Kiyoung Kim,Eung Suk Kim,Seung-Young Yu 대한안과학회 2019 Korean Journal of Ophthalmology Vol.33 No.6

Purpose: To evaluate the efficacy of focal verteporfin photodynamic therapy (PDT) in patients diagnosed with chronic central serous chorioretinopathy (CSC). Methods: This study enrolled 52 eyes of 52 patients with chronic CSC who had received verteporfin PDT. The laser spot size of 26 eyes covering only the localized hyperfluorescent area in indocyanine green angiography was classified as focal PDT. The PDT spot size of the other 26 eyes covered the total area of retinal pigment epithelial detachment including the leaking point and was defined as conventional PDT. The central subfield thickness and subfoveal choroidal thickness were measured using Heidelberg Spectralis optical coherence tomography before PDT and at months 1, 3, 6, and 12 after PDT. Results: The mean spot size of the PDT was 1,995 μm in the focal group and 2,995 μm in the conventional group. Central subfield thickness steadily decreased in both groups. The mean baseline subfoveal choroidal thickness for the two groups was 334.95 and 348.35 μm, respectively, with no significant difference (p = 0.602). Subfoveal choroidal thickness decreased significantly to 304.20 μm at 1 month, 284.85 μm at 3 months, 271.60 μm at 6 months, and 265.95 μm at 12 months in the focal group (p < 0.001, p < 0.001, p < 0.001, and p < 0.001, respectively, compared with baseline). In the conventional group, subfoveal choroidal thickness decreased significantly to 318.75, 300, 284, and 272 μm at 1, 3, 6, and 12 months, respectively (p < 0.001, p < 0.001, p < 0.001 and p < 0.001 compared with baseline). There were no significant differences between the two groups in subfoveal choroidal thickness based on PDT spot size at 1, 3, 6, and 12 months (p = 0.633, p = 0.625, p = 0.676, and p =0.755, respectively). Conclusions: Focal verteporfin PDT for CSC significantly decreased the subretinal fluid and sufoveal choroidal thickness to the same extent as conventional PDT.

IT를 통한 고용창출 : 정책 이슈와 제안

성태윤,박찬희,박기영 한국정보사회진흥원 2009 정보화정책 Vol.16 No.2

본 연구는 IT 산업 발전이 고용에 미치는 직·간접적 효과에 대한 기존의 여러 논의들을 정리하고, IT를 통한 고용창출에 있어서 정부의 바람직한 역할에 대해 논의한다. IT 기술발전이나 투자가 고용에 미치는 영향에 대한 기존 연구들은 먼저 IT 기술발전에 따라 고용은 직접적으로는 감소한다는 입장, 전반적으로는 고용이 증가할 수 있다는 입장, 그리고 마지막으로 고용 자체의 변화보다는 인력구성이 변화한다는 입장으로 크게 정리가능하다. IT 산업은 특히 산업 자체의 성격상 외부효과 및 다른 산업으로의 파급효과가 큰 산업이므로, IT를 통한 고용창출 효과를 논의할 때에는 직접적인 산업 내의 고용효과뿐만 아니라 간접적인 고용창출 효과, 신사업 창출, 생산성 향상 효과를 구분하여 함께 고려하여야 한다. 그리고 정부의 투자는 특정 산업 및 기업에 대한 직접 지원보다는 대체인력흡수 지원기반 조성에 노력하고 동시에 민간 부분의 수요창출을 통한 외부효과가 큰 기간설비(infrastructure)에 상대적으로 더 집중되어야 하며, 이를 기반으로 기업들이 자발적인 투자와 경쟁을 할 때 고용효과도 극대화될 수 있다. 따라서 산업인프라 조성에 있어서 민간부분의 수요를 반영할 수 있는 체계를 갖추는 것 역시 중요하다. This paper reviews previous studies on how the development of the IT industry directly and indirectly affects employment in the economy and discusses the appropriate role of the government in maintaining and creating jobs. The results of previous studies on effects of IT development and investment on employment could be classified into three major categories. First, IT development directly reduces employment. Second overall employment could increase. Third, composition of workforce rather than employment itself could change. When discussing the employment effect of IT, policymakers should take into account not only direct employment in the industry but also indirect effects including job creation in other industries, new business creation and productivity growth, since the IT industry exerts positive externality and feedback effects to other industries. Government investment should be focused on infrastructures, which have positive externality effects by creating demands in the private sector, not on direct support for specific firms or industries. In addition, the government should make efforts to lay a foundation for absorbing labor released from the current employment. Accordingly, constructing infrastructures should accompany a system that reflects the private sector's demand.