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Rediscovery of haploid breeding in the genomics era (유전체 시대에 반수체 육종의 재발견)

  • Lee, Seulki;Kim, Jung Sun;Kang, Sang-Ho;Sohn, Seong-Han;Won, So Youn
    • Journal of Plant Biotechnology
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    • v.43 no.1
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    • pp.12-20
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    • 2016
  • Advances in DNA sequencing technologies have contributed to revolutionary understanding of many fundamental biological processes. With unprecedented cost-effective and high-throughput sequencing, a single laboratory can afford to de novo sequence the whole genome for species of interest. In addition, population genetic studies have been remarkably accelerated by numerous molecular markers identified from unbiased genome-wide sequences of population samples. As sequencing technologies have evolved very rapidly, acquiring appropriate individual plants or populations is a major bottleneck in plant research considering the complex nature of plant genome, such as heterozygosity, repetitiveness, and polyploidy. This challenge could be overcome by the old but effective method known as haploid induction. Haploid plants containing half of their sporophytic chromosomes can be rapidly generated mainly by culturing gametophytic cells such as ovules or pollens. Subsequent chromosome doubling in haploid plants can generate stable doubled haploid (DH) with perfect homozygosity. Here, classical methodology to generate and identify haploid plants or DH are summarized. In addition, haploid induction by epigenetic regulation of centromeric histone is explained. Furthermore, the utilization of haploid plant in the genomics era is discussed in the aspect of genome sequencing project and population genetic studies.

Chemical Structures and Physiological Activities of Plant Growth Substance, Malformin A's (식물생장조절물질 말포민 A동족체의 화학구조 및 생리활성)

  • Kim, K.W.
    • Korean Journal of Weed Science
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    • v.15 no.1
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    • pp.73-84
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    • 1995
  • Four malformin A's produced by Aspergillus niger van Tiegh. were separated by HPLC equipped with $C_{18}$ reversed-phase column and subjected to structural determination. Amino acid analyses and mass spectra data of the compounds indicate that they structurally resemble the cyclic pentapeptide malformin $A_1$. Their structures were deduced by two dimensional NMR and MS/MS experiments as cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Ile for $A_1$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Val for $A_2$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Leu for $A_3$, and cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Val for $A_4$. Among the mal-formin A's, the structure of $A_3$ was identical to that of malformin C, which was produced by A. niger strain AN-1. All the malformin A's caused severe curvatures of corn(Zea mays L.) roots and the activities of the malformin A's with molecular weight 529 were greater than those with molecular weight 515. Malformin $A_1$ caused the corn root curvature by 83% at a concentration of $0.25{\mu}M$. In the mung bean(Phaseolus aureus Roxb.) hypercotyl segment test, however, the molecular weight of malformin A's was not a factor influencing the physiological activities. Malformin $A_1$ stimulated the growth of mung bean hypercotyles by 165% at a $0.1{\mu}M$ concentration.

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An Exploratory Study on the Applicability of Thin-Film Photovoltaic Cells for Auxiliary Power Supply of a Personal Rapid Transit (PRT) Vehicle (PRT 차량의 보조 전력공급을 위한 유연소재 태양전지의 적용 가능성 연구)

  • Kang, Seok-Won;Han, Soo-Jin;Jeong, Rag-Gyo;Oh, Hyuck Keun;Ko, Sangwon;Choi, Dooho
    • Journal of the Korean Society for Railway
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    • v.17 no.2
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    • pp.94-99
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    • 2014
  • Recently, trends in new transportation system development have been primarily focused on sustainable and ecofriendly mobility solutions. The personal rapid transit (PRT) system has been considered a promising candidate in this category; its competitiveness is being improved through convergence with cutting-edge electric vehicle (EV) technologies. However, battery-powered vehicles pose difficult technical challenges in attempts to achieve reliable and efficient operation. In this study, a design approach for a solar-power assisted PRT system is presented with small-scale demonstrations aimed at circumventing challenges facing its adoption, as well as helping speed the transition to electric-powered ground transportation. From the results, it is expected that flexible photovoltaic (PV) cells will be able to supply 11% of the power required by the service equipment installed in a prototype vehicle. In particular, flexible photovoltaic (PV) cells are advantageous in terms of cost, weight, and design considerations. Most importantly, the cells' flexibility and attach-ability are expected to give them great potential for extended application in various areas.

Design and Implementation of Wireless Power Transfer System for a Personal Rapid Transit (PRT) Vehicle (PRT 차량의 무선급전 시스템 설계 및 구현)

  • Kang, Seok-Won;Jeong, Rag-Gyo;Byun, Yeun-Sub;Um, Ju-Hwan;Kim, Baek-Hyun
    • Journal of Digital Convergence
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    • v.12 no.11
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    • pp.289-298
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    • 2014
  • Recently, the traditional paradigm in railroad technology is changing as more efficient and cost-effective electric vehicle (EV) technologies have emerged. The original concept of PRT (Personal Rapid Transit) proposed in the past has come to be regarded as unrealistic, but its feasibility is improving through the utilization of an EV platform. In particular, battery-powered vehicles pose difficult technical challenges in attempts to achieve reliable and efficient operation. However, based on the inductive power transfer (IPT) technology, the fast charging of supercapacitors with high energy density can contribute to overcoming this technical challenge and promote the transition to electric-powered ground transportation by improving the appearance of cities. This study discusses the development process of a power supply system for PRT, including concept design, numerical analysis, and device manufacturing, along with performance predictions and evaluations. In terms of results, the system was found to meet the performance requirements for power supply modules on a test-bed.

Mediating effect of growth mindset and grit between human rights victimization and self-esteem (인권피해와 자아존중감과의 관계에서 성장 마인드셋과 그릿의 매개효과)

  • Lee, Chang Seek;Park, Ji Young;Daniel, Nanje Bakoma;Ngonde, Sylvia;Faith, Akunne;Eboka, Mediki Augustine;Pamella, Ma Nsume
    • Journal of Digital Convergence
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    • v.15 no.9
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    • pp.15-21
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    • 2017
  • Our current study aimed to verify the mediating effect of growth mindset and grit in the relationship between human rights victimization and self-esteem. The survey was conducted on 233 college students. Reliability analysis, correlation analysis, and Macro Process were performed, and bootstrap method was used to verify the mediating effect of growth mindset and grit. The results were as follows. First, human right victimization were significantly and negatively correlated with self-esteem, growth mindset, and grit while self-esteem were significantly and positively correlated with growth mindset, and grit. Second, as a result of path analysis, the human rights victimization had a significant negative impact on self-esteem, growth mindset and grit. On the other hand, growth mindset and grit had a significant positive effect on self-esteem. Third, growth mindset and grit had a mediating effect in the relationship between human right victimization and self-esteem. This implied that self-esteem of college students can be increased by increasing their growth mindset and grit. Future research is needed to clarify the role of human rights research and growth mindset and self - esteem in college students.

The evaluation of image-guided catheter drainage in pleural effusion and empyema (흉수 및 농흉에서의 영상유도하 도관배액술의 유용성 평가)

  • Chang, Jung-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.3
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    • pp.403-409
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    • 1996
  • Background : Pleural fluid collections may pose a difficult therapeutic problem. Complete drainage of complicated effusions or empyemas and reexpansion of atelectatic lung are important in obtaining a satisfactory clinical outcome. The usual approach to the diagnosis and treatment of patients with pleural effusion and empyema has been with needle thoracentesis and chest tube drainage. With chest tube drainage, technical difficulties and failures may occur as a result of improper tube drainage, particularly when there is a loculation or multiple and inaccesible collections. Fluoroscopic or sonographic guidance facilitates the proper tube insertion and drainage. Method : Twenty eight patients were required for tube drainage due to pleural fluid collections between January 1994 to February 1996. The author compared the results of drainage under applying each different method between blind chest tube insertion and image guided catheter insertion. Results : The conventional blind chest tube group comprised 14 patients; 6 empyema, 6 tuberculous effusion, and 2 parapneumonic effusion. The image guided catheter group of smaller french were composed of 14 patients; 2 empyema, 6 tuberculous effusion, 5 parapneumonic effusion, and 1 effusion of undetermined origin. Radiologic improvement with successful drainage was noticed in 79% with the blind chest tube group, whereas in 93% with the image guided catheter group. The complication with the latter method was unremarkable. Conclusion : Image guided catheter drainage was safe and highly successful in treating patients, not only with complicated effusion also with loculated empyema. Image guided catheter drainage offers an alternative in patients in whom closed drainage is required as the initial treatment.

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A Feasibility Study of Green Frame(GF) for the Implementation of Low-carbon Emissions & Long-life Housing (저탄소 및 장수명 공동주택 구현을 위한 Green Frame(GF)의 타당성 분석)

  • Hong, Won-Kee;Kim, Sun-Kuk;Kim, Hyung-Geun;Yoon, Tae-Ho;Yune, Dai-Young;Kim, Seung-Il
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.1
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    • pp.57-63
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    • 2010
  • The bearing wall apartments which occupy the majority of multi-residential apartment buildings built in Korea, are known for having limited architectural plan flexibility, posing challenges in terms of maintenance and remodeling. The economic losses and environmental issues resulting from the reconstruction of bearing wall apartments are now accumulating to the extent that they are becoming a national concern. Multi-residential apartment buildings, which are now the dominant form of residence in Korea, must accommodate diverse customer needs and changes in life style. A new concept of Rahmen structure with architectural flexibility is Green Frame. GF multi-residence housing is expected to reduce construction costs and shorten the construction schedule by overcoming the shortcomings of conventional bearing wall apartments. This goal is consistent with the national policies that target the reduction of resource and energy consumption. In addition, GF will be established as a core contributor to achieving a reduction in $CO_2$ emissions, which will enable the sustainable growth of domestic construction industry, and address the low-carbon green growth drive implemented by the government.

A Study for Raising up Entrepreneurship Facilitators with having Angel Investing Potentials to Promote "Creative Entrepreneurship" (창조형창업 활성화를 위한 엔젤투자역량 겸비 창업 Facilitators 양성방안 연구)

  • Yang, Young Seok;Hwangbo, Yun;Byun, Young Jo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.8 no.3
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    • pp.27-37
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    • 2013
  • In recent, Korean government TF Team announced new entrepreneurship policy of establishing virtuous cycle in high-tech venture startup financing ecosystem with emphasizing on 'boosting up angel investment and M&A.' This policy is brought not only to come up with the previous policy defects of creating less creative starts-up despite that government has put die-hard efforts, such as big chunk of budget dumping and policy preference, to promote high-tech starts-up since the year of 1997, but also to found right momentum of shifting entrepreneurship policy paradigm from government-direct to entrepreneur into indirect via utilizing the market forces. In particular, this policy puts a highlight on promoting angel investment, representing unfolding red carpets for creative economy. However, this policy confront critical fatal flaws such as a serious lacks of business angels which carry out the core function of government policy. In worse off, business angels cannot be raised up in short term period by taking other practical entrepreneurship ecosystem cases. As alternative, this paper propose the raising-up over entrepreneurship facilitators with having angel investing potentials in short term. In specific, this paper suggest the training methodology over the previous BI manager, passive simple angel investors, and consultants in entrepreneurship for embedding entrepreneurship facilitators. This paper carries four different specific studies. First, this paper implement literature review for entrepreneurship policy with respect to evaluating the previous entrepreneurship policies and making a diagnosis over its consequences. Second, it carries theoretical literature reviews relating to Korean angel investment and business incubation. Third, it proposes the concept of entrepreneurship facilitators. Fourth, it brings the alternatives of raising up entrepreneurship facilitators.

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The Four Color Algorithm (4-색 알고리즘)

  • Lee, Sang-Un
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.5
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    • pp.113-120
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    • 2013
  • This paper proposes an algorithm that proves an NP-complete 4-color theorem by employing a linear time complexity where $O(n)$. The proposed algorithm accurately halves the vertex set V of the graph $G=(V_1,E_1)$ into the Maximum Independent Set (MIS) $\bar{C_1}$ and the Minimum Vertex Cover Set $C_1$. It then assigns the first color to $\bar{C_1}$ and the second to $\bar{C_2}$, which, along with $C_2$, is halved from the connected graph $G=(V_2,E_2)$, a reduced set of the remaining vertices. Subsequently, the third color is assigned to $\bar{C_3}$, which, along with $C_3$, is halved from the connected graph $G=(V_3,E_3)$, a further reduced set of the remaining vertices. Lastly, denoting $C_3$ as $\bar{C_4}$, the algorithm assigns the forth color to $\bar{C_4}$. The algorithm has successfully obtained the chromatic number ${\chi}(G)=4$ with 100% probability, when applied to two actual map and two planar graphs. The proposed "four color algorithm", therefore, could be employed as a general algorithm to determine four-color for planar graphs.

A Polynomial Time Algorithm for Vertex Coloring Problem (정점 색칠 문제의 다항시간 알고리즘)

  • Lee, Sang-Un;Choi, Myeong-Bok
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.7
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    • pp.85-93
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    • 2011
  • The Vertex Coloring Problem hasn't been solved in polynomial time, so this problem has been known as NP-complete. This paper suggests linear time algorithm for Vertex Coloring Problem (VCP). The proposed algorithm is based on assumption that we can't know a priori the minimum chromatic number ${\chi}(G)$=k for graph G=(V,E) This algorithm divides Vertices V of graph into two parts as independent sets $\overline{C}$ and cover set C, then assigns the color to $\overline{C}$. The element of independent sets $\overline{C}$ is a vertex ${\upsilon}$ that has minimum degree ${\delta}(G)$ and the elements of cover set C are the vertices ${\upsilon}$ that is adjacent to ${\upsilon}$. The reduced graph is divided into independent sets $\overline{C}$ and cover set C again until no edge is in a cover set C. As a result of experiments, this algorithm finds the ${\chi}(G)$=k perfectly for 26 Graphs that shows the number of selecting ${\upsilon}$ is less than the number of vertices n.