검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 491

        104.
        2019.04 구독 인증기관·개인회원 무료
        An investigation on the habitation of Callipogon relictus Semenov was carried out in Gwangneung forest, Korea and Ussurisky nature reserve, Russia. During the investigation period (2007–2018), a total of 25 emergence holes, 10 pupal chambers, 10 adults, and two larvae of C. relictus were identified in Gwangneung forest. In this presentation, we provide biological information on habitation of C. relictus in Gwangneung forest by comparison and combination of survey results in Ussurisky nature reserve, in 2015 and 2018. In addition, the distribution range of C. relictus is also reviewed in the Korean Peninsula with a new location.
        105.
        2019.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The KVN(Korean VLBI Network)-style simultaneous multi-frequency receiving mode is demonstrated to be promising for mm-VLBI observations. Recently, other Very long baseline interferometry (VLBI) facilities all over the globe start to implement compatible optics systems. Simultaneous dual/multi-frequency VLBI observations at mm wavelengths with international baselines are thus possible. In this paper, we present the results from the first successful simultaneous 22/43 GHz dualfrequency observation with KaVA(KVN and VERA array), including images and astrometric results. Our analysis shows that the newly implemented simultaneous receiving system has brought a significant extension of the coherence time of the 43 GHz visibility phases along the international baselines. The astrometric results obtained with KaVA are consistent with those obtained with the independent analysis of the KVN data. Our results thus confirm the good performance of the simultaneous receiving systems for the non-KVN stations. Future simultaneous observations with more global stations bring even higher sensitivity and micro-arcsecond level astrometric measurements of the targets.
        4,000원
        106.
        2019.02 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies with high probabilities of hosting supernovae (SNe). IMSNG aims to constrain the SN explosion mechanism by inferring sizes of SN progenitor systems through the detection of the shock-heated emission that lasts less than a few days after the SN explosion. To catch the signal, IMSNG utilizes a network of 0.5-m to 1-m class telescopes around the world and monitors the images of 60 nearby galaxies at distances D < 50 Mpc to a cadence as short as a few hours. The target galaxies are bright in near-ultraviolet (NUV) with MNUV < - 18.4 AB mag and have high probabilities of hosting SNe (0.06 SN yr-1 per galaxy). With this strategy, we expect to detect the early light curves of 3.4 SNe per year to a depth of R  19:5 mag, enabling us to detect the shock-heated emission from a progenitor star with a radius as small as 0.1 R . The accumulated data will be also useful for studying faint features around the target galaxies and other science projects. So far, 18 SNe have occurred in our target fi elds (16 in IMSNG galaxies) over 5 years, confi rming our SN rate estimate of 0.06 SN yr-1 per galaxy.
        4,200원
        110.
        2018.11 구독 인증기관·개인회원 무료
        Sex preselection has always generated great interest among livestock producers due to an increase in the profitability of the cattle industry through the production of offspring with desired sex, such as females for dairy or males for meat production. Among the prevalent sorting methods, the embryo developmental potential is still very low as expected, and there is distinguished evidence that sex sorting has a negative effect on sperm quality with an altered pattern of sperm motility, ultimately reducing lifespan. The consequence is a very low embryo development rate using sex-sorted semen, and its negative impact influences the progress of the dairy industry. Here, we established a new approach with reduced stress by using WholeMom® and observed no significant differences (P < 0.05) in early cleaving embryos between sorted X sperm and the control group, although there was a remarkable significant difference in embryos of the Y sperm group, 81.82 ± 2.71% vs. 87.44 ± 3.02% vs. 54.21 ± 2.21%, respectively. The percentage of embryos that developed into blastocysts (Day 7) was also significantly (P < 0.05) higher in the control and X Sperm group compared to the Y sperm group, 35.53 ± 1.92% and 29.76 ± 2.38% vs. 21.90 ± 1.54%. Moreover, B-SRY F2 and B-SRY R2 gene expression data exhibited 81.03% accuracy for the female embryos and 72.54% for the male embryos produced in vitro. And also the field trials for the heifer production using WholeMom by Artificial Insemination technique demonstrated 76% female and 24% male in vivo. In conclusion, the combination of pre-selected sex semen and OPU derived elite cattle embryo production is highly recommended to apply to the mass production in the dairy industry with rapid genetic up-gradation.
        111.
        2018.11 구독 인증기관·개인회원 무료
        The embryonic genome activation (EGA) is genetically activated states that embryos make the materials such as growth factors for using themselves. EGA is various because they have many materials, different site, different stage, also different species. At this time, transcription factors are expressed. Transcription factors bind to specific DNA region, and regulate the gene expression. Thus, we check the expression of transcription factors, we can know that embryo development is very well or not. The development stages of embryos are basically the stages from fertilization to blastocyst. So, we check the embryos oocyte to blastocyst. In our experiments, we focus the early developmental transcription factors such as Cdx2, Oct4, Sox2, Nanog and E-Cadherin. Above antibody factors showed different expression sites, and there were many differentiated parts from other animal species. In addition, we compared the SCNT and parthenogenetic activation (PA) because these are same methods using electrical activation among the embryo production methods. Our results showed not only similar patterns but also different patterns between pig and mouse. Therefore, we have to investigate that different patterns of transcription factors play a role in pigs, and why occur.
        115.
        2018.10 구독 인증기관·개인회원 무료
        Geminiviruses are plant-infecting viruses with monopartite or bipartite single-stranded circular DNA genomes. They are known to be mediated by insects such as whiteflies, treehoppers, leafhoppers or aphids and can cause devastating plant diseases in a wide range of economically significant crops worldwide. In Korea, occurrence of geminiviruses were reported officially after the 2000s. Although Honeysuckle yellow vein virus (HYVV) and Sweet potato leaf curl virus (SPLCV) were identified from honeysuckle and sweet potato in 2004 and 2006 respectively, these viruses did not spread and cause much concern for geminiviruses. In 2008, Tomato yellow leaf curl virus (TYLCV) that has caused severe tomato production loss in many subtropical and tropical countries was first reported in tomato plants cultivated in Tongyeong. TYLCV rapidly spread through the country and has been continuously reported from tomato cultivating areas in Korea. In addition to TYLCV, Tobacco leaf curl virus and Sweet potato golden vein associated virus have occurred. In recent years, new geminiviruses including Papaya leaf curl Guangdong virus (PaLCGdV) and Euphorbia leaf curl virus (EuLCV) have been introduced. Newly emerging geminiviruses from tropical and subtropical countries are due to increased demand for various fruits and vegetables, and climate change. In addition, there are reports that some geminiviruses including TYLCV can be transmitted by infected seeds. Therefore it is important to study on epidemiology of virus introduction and spread among the countries and within country.
        117.
        2018.07 구독 인증기관·개인회원 무료
        Export diversification – the extent to which the firm seizes export sales opportunities across different nations and/or geographic regions – is a critical element of export marketing strategy. Yet, knowledge of the export performance consequences of export diversification is lacking. Underpinned by contingency and resource dependence theories, we examine the export diversification-export performance relationship as well as critical contingencies of this link. Based on a sample of UK exporters we find that firms gain the highest export performance benefits when they simultaneously increase national and regional export diversification. Our results also show that the export diversification-export performance link is weaker when firms operate in markets that are very in dynamism. Additionally, the relationship between export diversification and performance is stronger when both resource sharing and interfunctional coordination are high. Such contextual factors provide a better understanding of the diversification-performance relationship.
        118.
        2018.07 구독 인증기관·개인회원 무료
        Researchers have yet to investigate whether it is beneficial for exporters to engage in greater levels of product adaptation in their export operations, or whether there is some limit to the amount of adaptation exporters should engage in. We posit that customer value creation, a central marketing concept and a mechanism to achieving market and financial goals in business to business markets, is a core outcome of export product adaptation activities. In order to explore the routes by which adaptation may shape export customer value creation, we adopt a multi-faceted conceptualization of firm-level product adaptation, comprising export product adaptation (i) quantity, (ii) intensity and (iii) novelty. Drawing on survey data from 249 Finnish exporters involved in business-to-business activities, we find evidence to support the claim that the impact of export product adaptation on export customer value creation is contingent on various factors, and we identify instances where greater adaptation is beneficial for export customer value creation, and instances where greater export product adaptation is potentially harmful for export customer value creation.
        119.
        2018.07 구독 인증기관·개인회원 무료
        As visual marketing gains a more critical role in marketing communications, consumer eye-tracking data has been utilized to assess the effectiveness of those marketing efforts (Croll, 2016; Glazer, 2012). With eye-tracking data, researchers can capture consumers’ visual attention effectively and may predict their behavior better than with traditional memory measures (Wedel & Pieters, 2008). However, due to the complexity of data: its volume, velocity and variety, known as 3Vs of Big Data, marketing scholars have been slow in fully utilizing eye-tracking data. These data properties may pose a challenge for researchers to analyze eye-tracking data, especially gaze sequence data, with traditional statistical approaches. Commonly, researchers may analyze gaze sequences by computing average probabilities of gaze transitions from a particular area of interest to another area of interest. When the variance of gaze sequence data in the sample is small, this method would uncover a meaningful “global” trend, a trend consistent across all the individuals. However, when the variance is large, this method may not enable researchers to understand the nature of the variance, or the “messiness” of data. In this paper, first, to overcome this challenge, we propose an innovative method of analyzing gaze sequence data. Utilizing the singular value decomposition, our proposed method enables researchers to reveal a “local” trend, a trend shared by only some individuals in the sample. Second, we illustrate the benefits of our method through analyzing gaze sequence data collected in an advertising study. Finally, we discuss the implications of our proposed method, including its capability of uncovering a hidden “local” trend in “messy” gaze sequence data.
        120.
        2018.07 구독 인증기관·개인회원 무료
        As brands’ use of social media to connect with customers becomes increasingly important, there is a need to continually monitor and examine activities in social networks. An important aspect of the social network communications is its unique ways of concentrating and dispersing information among participants (actors) – density and centrality of the network. By looking at both density and centrality, the relationships among actors and their ability to influence others are revealed, allowing deeper understanding into networked behaviors. In this manner, examining whole and ego network patterns, the unique roles of individual actors, can provide brands significant insight in understanding how influencers form and how users connect and spread information. Based on the social network analysis, which represents a combination of theory and analytical methods of networked relationships, this study analyzed Twitter networks of two multi-brand cosmetics and beauty retailers, Sephora (global brand) and Ulta Beauty (U.S. domestic brand). Using NodeXL, daily Twitter data for both brands were gathered to investigate network activities. By examining both ego-networks and the whole networks, the results showed that while ego-networks for brands were quite similar to one another, there was a big difference between the ego-networks and whole networks in regards to the number of actors, type of connectivity, as well as the prominence of brands. Sephora was often not an important part of its hashtag network, and thus was not able to maintain strong control over communications and messages in these networks whereas Ulta maintained its control over its networks. The findings from analyzing these network patterns, the unique roles of individual actors, and the brands within the networks provide significant insights in understanding how influencers form and develop the ability to connect and spread information.