• Journal of the korean veterinary medical association
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• v.9 no.1
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• pp.12-15
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• 1965

An outbreak during the summer of 1965 of Piroplasmosis caused by Theileria mutans among imported dairy cattle located at Sungwhan, Iri and Chunju, is described. As is well known, this parasite usually does not show any clinical signs but this case, we obs

• Journal of The Korean Astronomical Society
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• v.13 no.1
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• pp.27-33
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• 1980

Surface density distributions for globular clusters were obtained from photoelectric surface photometry (using centered aperture photometry). These surface brightness profiles were then compared with the theoretical surface density distribution of King's model. From the comparison of the theoretical and observed surface density distributions, we determine he structural parameters of the clusters (the core radius $r_c$, the tidal cut off $r_t$, and the concentration factor C).

• Information and Communications Magazine
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• v.26 no.6
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• pp.37-44
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• 2009

오늘날 다수의 빔과 주파수를 사용하는 통신위성은 고속 디지털 신호 처리를 응용한 부채널 단위의 OBS(On-board Switching) 기술과 원하지 않는 간섭신호를 일정부분 제거하는 기능을 필요로 하게 될 전망이다. 본고에서는 위성통신 분야에서 현재 활발히 연구가 진행되고 있는 부채널 수준의 스위칭이 가능한 수동형 디지털 통신위성에 대하여 소개한다. 아울러 위성 선진국의 디지털 통신위성 개발 현황, 부채널 증폭 및 스위칭을 위한 소요기술, 그리고 간섭신호 제거가 가능한 디지털 통신위성 기술에 대하여 기술한다.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.287-287
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• 2004

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1981-1985
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• 2005

Kinetic studies have been performed for alkaline hydrolysis of a series of [(methoxy)(p-substituted styryl)carbene]pentacarbonyl chromium(0) complexes ($(CO)_5$Cr=$C(OCH_3)CH=CHC_6H_4X$, X = p-$OCH_3$, p-$CH_3$, H, p-Cl, p-$NO_2$). Second-order rate constants $(k_{{OH}^-})$ for the alkaline hydrolysis in 50% acetonitrile-water(v/v) were determined spectrophotometrically at various temperatures. At a low pH region (pH < 7.5), the observed rate constant $(k_{obs})$ remained constant with a small value, while in a high pH region (pH > 9.5), $k_{obs}$ increases linearly with increasing the pH of the medium. The second-order rate constants $(k_{{OH}^-})$ increase as the substituent X changes from a strong electron donating group to a strong electron withdrawing group. The Hammett plot obtained for the alkaline hydrolysis is consisted of two intersecting straight lines. The nonlinear Hammett plot might be interpreted as a change in the rate-determining step. However, the fact that the corresponding Yukawa-Tsuno plot is linear with $\rho$ and r values of 0.71 and 1.14, respectively indicates that the nonlinear Hammett plot is not due to a change in the rate-determing step but is due to ground-state stabilization through resonance interaction. The positive $\rho$ value suggests that nucleophilic attack by $OH^-$ to form a tetrahedral addition intermediate is the rate-determining step. The large negative ${\Delta}S^\neq$ value determined in the present system is consistent with the proposed mechanism.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1043-1053
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• 2017

In this study, genotyping was executed by using 13 microsatellite markers for genetic diversity of 224 Gorals (Saanen(88), Laoshan(67), Toggenburg(32), Alpine(12), Anglonubian(9), Jamnapari(7) and Black Bengal(4)). The number of alleles was observed 4 (INRA005) to 18 (SRCRSP23) each markers. Observed heterozygostiy ($H_{obs}$), expected heterozygosity ($H_{\exp}$) and polymorphism information content (PIC) were observed 0.482 to 0.786, 0.476 to 0.923, and 0.392 to 0.915, respectively. Principal Components Analysis(PCoA) results were similar to the results of FCA. NE-I(on-exclusion probability for identity of two unrelated individuals) was estimated at $2.47{\times}10^{-15}$. In conclusion, this study shows the useful data that be utilized as a basic data of Gorals breeding and development.

• Reproductive and Developmental Biology
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• v.35 no.1
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• pp.105-113
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• 2011

The present study investigated the nuclear remodeling, development potential with telomerase activity and transcription level of X-linked genes (ANT3, HPRT, MeCP2, RPS4X, XIAP, XIST and ZFX) in the bovine somatic cell nuclear transfer (SCNT) embryos using two different fusion and activation methods. Female adult fibroblasts were injected into perivitelline space of in vitro matured oocytes. The oocyte-nucleus complexes were fused and followed by immediately either activated (Group 1), or activated at 1 h post-fusion (hpf) (Group 2), respectively. The incidence of normal premature chromosome condensation (PCC) at 1 hpf was slightly increased in the Group 2, compared to those of Group 1, but there was no significant (p<0.05) difference. The incidence of normal pronucleus (PN) and chromosome spread at 5 and 18 hpf were significantly (p<0.05) higher in the Group 2 than those of Group 1. The cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cell numbers were significantly (p<0.05) higher in the Group 2, compared to those of Group 1. Level of telomerase activity was significantly (p<0.05) higher in the SCNT blastocysts of Group 2, compared to those of Group 1. Transcript levels of HPRT, MeCP2 and XIST were not significantly (p<0.05) different between blastocysts of Group 1 and 2. However, transcript level of ANT3, RPS4X, XIAP and ZFX were significantly (p<0.05) up-regulated in the SCNT blastocysts of Group 2, compared to those of Group 1. Taken together, it is concluded that oocyte activation at 1 hpf induces the enhanced developmental potential by efficient nuclear remodeling and subsequent facilitation of the nuclear reprogramming of bovine SCNT embryos.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.34-39
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• 2005

In this paper, we propose a new prioritized Optical Burst Switching (OBS) protocol based on a hop count, which can provide an efficient utilization in optical Wireless networks. Under several legacy schemes, a switch drops the burst with a shorter time among ones regardless of its traversed hop count. As a result, the dropped burst that have been traversed more hops might cause to waste bandwidth than the one traversed a few hops. Noting that this problem, we propose the Just Enough Time(JET) with a hop count scheme which can reduce the wasted bandwidth by prioritizing the burst traversed more hops over others. From the simulation result, we show that the proposed scheme is advantageous over the legacy schemes in terms of the burst blocking probability and the link utilization.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.397-401
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• 2006

A laboratory study was conducted to evaluate the kinetics of oxidation of trichloroethylene(TCE) in groundwater by potassium permanganate($KMnO_4$). Consumption of permanganate by TCE and aquifer material was also evaluated to obtain an appropriate injection rate of $KMnO_4$. TCE degradation by $KMnO_4$ in the absence of aquifer material was effective with a pseudo-first order rate constant, $k_{obs}=5.24{\times}10^{-3}s^{-1}\;at\;KMnO_4=500mg/L$. TCE oxidation by $KMnO_4$ was found to be second order reaction and the rate constant, $k=0.65{\pm}0.08M^{-1}s^{-1}$. Meanwhile, aquifer materials from the field site were actively reacted with permanganate, resulting in the significant consumption of $KMnO_4$. It might be attributed to the existence of metal oxides in the aquifer materials.

• Steel and Composite Structures
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• v.19 no.4
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• pp.917-937
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• 2015

During a seismic event, a considerable amount of energy is input into a structure. The law of energy conservation imposes the restriction that energy must either be absorbed or dissipated by the structure. Recent earthquakes have shown that the use of concentric bracing system with their low ductility and low energy dissipation capacity, causes permanent damage to structures during intense earthquakes. Hence, engineers are looking at bracing system with higher ductility, such as chevron and eccentric braces. However, braced frame would not be easily repaired if serious damage has occured during a strong earthquake. In order to solve this problem, a new bracing system an off-centre bracing system with higher ductility and higher energy dissipation capacity, is considered. In this paper, some numerical studies have been performed using ANSYS software on a frame with off-centre bracing system with optimum eccentricity and circular element created, called OBS_C_O model. In addition, other steel frame with diagonal bracing system and the same circular element is created, called DBS_C model. Furthermore, linear and nonlinear behavior of these steel frames are compared in order to introduce a new way of optimum performance for these dissipating elements. The obtained results revealed that using a ductile element or circular dissipater for increasing the ductility of off-centre bracing system and centric bracing system is useful. Finally, higher ductility and more energy dissipation led to more appropriate behavior in the OBS_C_O model compared to DBS_C model.