• Title/Summary/Keyword: Exploration #5

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Introduction to Chang'e-3 and Analysis of Estimated Mission Trajectory (창어 3호 개요 및 임무궤적 추정결과 분석)

  • Choi, Su-Jin;Lee, Donghun;Bae, Jonghee;Rew, Dong-Young;Ju, Gwanghyeok;Sim, Eun-Sup
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.11
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    • pp.984-997
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    • 2015
  • Chang'e-3 consisting of a lunar lander and exploration rover was launched on December 1, 2013 aboard a Long March 3B rocket flying from Xichang space launch center. Chang'e-3 was inserted into the lunar orbit after about a 5-day transit to the Moon and landed on the targeted landing site after orbiting around the Moon for 8 days. The successful landing of the Chang'e-3 gives a lot of help to analyze the future needs of the subsystem technologies and to figure out the trajectory from launch to lunar landing as well as operation sequences in the development of Korean lunar exploration is scheduled. Therefore, the configuration and analysis of overall mission of Chang'e-3 is performed based on the public information from the press and website. As a result, overall mission trajectory is reconstructed by solving boundary condition and then estimating control variable. Visibility status and eclipse status also analyzes so communication and power charge condition is as good as to operate lunar lander. Mass budget of the lander is derived using ${\Delta}V$ according to specific impulse.

Enrichment and verification of differentially expressed miRNAs in bursa of Fabricius in two breeds of duck

  • Luo, Jun;Liu, Junying;Liu, Hehe;Zhang, Tao;Wang, Jiwen;He, Hua;Han, Chunchun
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.7
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    • pp.920-929
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    • 2017
  • Objective: The bursa of Fabricius (BF) is a central humoral immune organ belonging specifically to avians. Recent studies had suggested that miRNAs were active regulators involved in the immune processes. This study was to investigate the possible differences of the BF at miRNA level between two genetically disparate duck breeds. Methods: Using Illumina next-generation sequencing, the miRNAs libraries of ducks were established. Results: The results showed that there were 66 differentially expressed miRNAs and 28 novel miRNAs in bursa. A set of abundant miRNAs (i.e., let-7, miR-146a-5p, miR-21-5p, miR-17~92) which are involved in immunity and disease were detected and the predicted target genes of the novel miRNAs were associated with duck high anti-adversity ability. By gene ontology analysis and enriching KEGG pathway, the targets of differential expressed miRNAs were mainly involved in immunity and disease, supporting that there were differences in the BF immune functions between the two duck breeds. In addition, the metabolic pathway had the maximum enriched target genes and some enriched pathways that were related to cell cycle, protein synthesis, cell proliferation and apoptosis. It indicted that the difference of metabolism may be one of the reasons leading the immune difference between the BF of two duck breeds. Conclusion: This data lists the main differences in the BF at miRNAs level between two genetically disparate duck breeds and lays a foundation to carry out molecular assisted breeding of poultry in the future.

Polymorphisms in the Perilipin Gene May Affect Carcass Traits of Chinese Meat-type Chickens

  • Zhang, Lu;Zhu, Qing;Liu, Yiping;Gilbert, Elizabeth R.;Li, Diyan;Yin, Huadong;Wang, Yan;Yang, Zhiqin;Wang, Zhen;Yuan, Yuncong;Zhao, Xiaoling
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.763-770
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    • 2015
  • Improved meat quality and greater muscle yield are highly sought after in high-quality chicken breeding programs. Past studies indicated that polymorphisms of the Perilipin gene (PLIN1) are highly associated with adiposity in mammals and are potential molecular markers for improving meat quality and carcass traits in chickens. In the present study, we screened single nucleotide polymorphisms (SNPs) in all exons of the PLIN1 gene with a direct sequencing method in six populations with different genetic backgrounds (total 240 individuals). We evaluated the association between the polymorphisms and carcass and meat quality traits. We identified three SNPs, located on the 5' flanking region and exon 1 of PLIN1 on chromosome 10 (rs315831750, rs313726543, and rs80724063, respectively). Eight main haplotypes were constructed based on these SNPs. We calculated the allelic and genotypic frequencies, and genetic diversity parameters of the three SNPs. The polymorphism information content (PIC) ranged from 0.2768 to 0.3750, which reflected an intermediate genetic diversity for all chickens. The CC, CT, and TT genotypes influenced the percentage of breast muscle (PBM), percentage of leg muscle (PLM) and percentage of abdominal fat at rs315831750 (p<0.05). Diplotypes (haplotype pairs) affected the percentage of eviscerated weight (PEW) and PBM (p<0.05). Compared with chickens carrying other diplotypes, H3H7 had the greatest PEW and H2H2 had the greatest PBM, and those with diplotype H7H7 had the smallest PEW and PBM. We conclude that PLIN1 gene polymorphisms may affect broiler carcass and breast muscle yields, and diplotypes H3H7 and H2H2 could be positive molecular markers to enhance PEW and PBM in chickens.

Identification of polymorphic loci in the deiodinase 2 gene and their associations with head dimensions in geese

  • Deng, Yan;Hu, Qian;Tang, Bincheng;Ouyang, Qingyuan;Hu, Shenqiang;Hu, Bo;Hu, Jiwei;He, Hua;Chen, Guohong;Wang, Jiwen
    • Animal Bioscience
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    • v.35 no.5
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    • pp.639-647
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    • 2022
  • Objective: This study was conducted to clone and compare the molecular characteristics of the deiodinase 2 (DIO2) gene between Sichuan White geese and Landes geese, and to analyze the association between polymorphisms of the DIO2 gene and head dimensions in Tianfu meat geese. Methods: The coding sequence of the DIO2 gene was cloned by polymerase chain reaction and vector ligation and aligned by DNAMAN software. A total of 350 Tianfu meat geese were used to genotype the polymorphisms of the DIO2 gene and measure the head dimensions. Association analysis between the polymorphisms of the DIO2 gene and head dimensions was carried out. Results: An 840-bp coding sequence of the DIO2 gene was obtained and comparison analysis identified four polymorphic loci between Sichuan White geese and Landes geese. Further analysis showed that the dominant alleles for the four polymorphic loci were G, G, A, and T and the frequency of the heterozygous genotype was higher than that of the homozygous genotype in Tianfu meat geese. Compared to that in the population of non-knob geese of Tianfu meat geese, the head dimensions in the population of knob geese were significantly higher except for nostril height. However, in the non-knob geese, beak width 1, beak width 2, nostril length, cranial width 1, and maxillary length had significant differences among different genotypes or haplotypes/diplotypes. Conclusion: These results suggested that polymorphisms of the DIO2 gene could be considered molecular markers to select larger heads of geese in the population of non-knob geese.

An Analysis of Illustrations in the 2009 Revised Elementary School Science Textbooks: Focus on Functions of Illustrations and Roles on 5E Inquiry Learning Process (5E 과학학습과정 상의 기능을 중심으로 한 2009 개정 초등과학교과서 삽화 분석: 3~4학년 지구과학 단원을 대상으로)

  • Kim, Jong-young;Ha, Ji-hoon;Lim, Heejun
    • Journal of Korean Elementary Science Education
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    • v.35 no.3
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    • pp.305-315
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    • 2016
  • The purpose of this paper was to analyze the role of illustrations in elementary textbooks (3~4 grade) of the 2009 revised curriculum of science education in Korea from point of view of aim of science by applying the criteria of 5E inquiry process model for reflecting core aim of the science education. The subjects of the paper was the 105 illustrations in the earth-science domain of elementary science textbooks (3~4 grade) of the 2009 revised curriculum of science education in Korea. The analysis criterion was of two categories, the function of illustration and the role of illustration. the function of illustration was divided into three subcategories such as Exclusiveness type, correspondence type and supplementary type. The role of illustration was divide into five subcategories such as Engagement, Exploration, Explanation, Elaboration and Evaluation. According to results of the illustration analysis are as follows: the result of the function of illustration are exclusiveness type 39, correspondence type 36 and supplementary type 30, the important of point to note is that there are a lot of exclusiveness type considerably. compared with other subjects, this fact indicate character of illustration of the only science textbook. The result of the role of illustration are Engagement 14, exploration 64, explanation 25, elaboration 2 and evaluation 0. This data indicate main role of illustrations in earth-science domain is to help the students to be able to observe and explore. Cross-analysis of the function and role was a significant difference. Role of illustration was evenly distributed within Exclusiveness type on the other hand, the role of illustrations was mainly exploration and explanation in correspondence and supplementary type. Especially, illustration of exploration was mainly correspondence type.

TRACING BRIGHT AND DARK SIDES OF THE UNIVERSE WITH X-RAY OBSERVATIONS

  • SUTO YASUSHI;YOSHIKAWA KOHJI;DOLAG KLAUS;SASAKI SHIN;YAMASAKI NORIKO Y.;OHASHI TAKAYA;MITSUDA KAZUHISA;TAWARA YUZURU;FUJIMOTO RYUICHI;FURUSHO TAE;FURUZAWA AKIHIRO;ISHIDA MANABU;ISHISAKI YOSHITAKA
    • Journal of The Korean Astronomical Society
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    • v.37 no.5
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    • pp.387-392
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    • 2004
  • X-ray observations of galaxy clusters have played an important role in cosmology, especially in determining the cosmological density parameter and the fluctuation amplitude. While they represent the bright side of the universe together with the other probes including the cosmic microwave background and the Type Ia supernovae, the resulting information clearly indicates that the universe is dominated by dark components. Even most of cosmic baryons turns out to be dark. In order to elucidate the nature of dark baryons, we propose a dedicated soft-X-ray mission, DIOS (Diffuse Intergalactic Oxygen Surveyor). Recent numerical simulations suggest that approximately 30 to 50 percent of total baryons at z = 0 take the form of the warm-hot intergalactic medium (WHIM) with $10^5K < T < 10^7K $which has evaded the direct detection so far. The unprecedented energy resolution (${\~} 2eV$) of the XSA (X-ray Spectrometer Array) on-board DIGS enables us to identify WHIM with gas temperature $T = 10^6 {\~} 10^7K$ and overdensity $\delta$ = 10 ${\~}$ 100 located at z < 0.3 through emission lines of OVII and OVIII. In addition, WHIMs surrounding nearby clusters are detectable with a typical exposure time of a day, and thus constitute realistic and promising targets for DIOS.

Lunar Exploration Satellite Communication Link Analysis (달 탐사 위성의 통신 링크 분석)

  • Kim, Ah-Leum;Lee, Seul-Ki;Lee, Woo-Kyung
    • Journal of Satellite, Information and Communications
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    • v.6 no.1
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    • pp.1-5
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    • 2011
  • In recent space industry, It has become a major trend to launch lunar exploration satellites to extend activities in the deep space environment. In this paper, a link budget analysis is carried out for the lunar exploration satellite. One of the major difference between the lunar satellite and LEO spacecraft lies in the orbit parameters. The vast distance between spacecraft and the Earth station imposes a challenging task for the spacecraft designers in terms of achieving stable communication link budget. The satellite tool kit software has been adopted to simulate the lunar exploring satellite. The relative distance between the spacecraft and the ground stations are tracked and the communication link budget is calculated accordingly.

Geochemical Exploration for the Bougouni Area in Mali (말리 부구니 지역에 대한 지화학탐사)

  • Kim, In-Joon
    • Economic and Environmental Geology
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    • v.41 no.5
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    • pp.563-575
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    • 2008
  • The ore depositional and geochemical exploration on Bougouni area in Mali, central-western Africa covering $2,000\;Km^2$ was conducted for determining the detailed survey area. According to the results of this exploration, the highly potential area for the zinc-tin-gold-silver mineralization was found in Kolani and Riarako areas. The contents of zinc in heavy sand collected in the stream sediments range from 14 to 8,600 ppm, while the mean values of zinc in this area are 543 ppm with threshold($x+2{\sigma}$) of zinc anomalies being 1,000 ppm in Bougouni area. Generally zinc anomalies are associated with the tin and molybdenum anomalies and hence the anomalous area was selected for the detailed survey area for tracing the primary zinc and precious ore deposits related to these anomalies in following project.

An Estimation Technique of Rock Mass Classes for a Tunnel Design (터널 설계를 위한 암반등급 산정 기법에 관한 연구)

  • 유광호
    • Journal of the Korean Geotechnical Society
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    • v.19 no.5
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    • pp.319-326
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    • 2003
  • In site investigation for tunnel designs, nowadays, geophysical exploration such as seismic exploration and electric resistivity exploration as well as drilling logging is frequently carried out. A method which can systematically make the utmost use of all available data obtained from investigation, therefore, is strongly required for the optimal evaluation of ground conditions in terms of rock mass class, etc. Many researchers have proposed using qualitative data to cope with the lack of quantitative data. In this study, an evaluation technique of rock mass classes in undrilled region was proposed based upon multiple indicator kriging method which is a geostatistical technique. It was shown that two types of data with different degree of uncertainty, for example, drilling logging data and geophysical exploration data, could be simultaneously utilized in evaluating rock mass classes for a real tunnel design.

The Contribution of Mergers on Star Formation in Nearby UV-Bright Galaxies (별탄생 은하의 별 생성에 대한 병합 작용의 기여도 연구)

  • Lim, Gu;Im, Myungshin;Choi, Changsu;Yoon, Yongmin
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.70.2-70.2
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    • 2016
  • Star formation in galaxies is one of the key factors in galaxy evolution. It is believed that star formation is triggered and enhanced by mergers among galaxies or secular evolution. However, how much these two mechanisms contribute on star formation is not well known yet. Recently, many other studies show observational evidences of faint merger features(tidal tails, stellar streams) around nearby galaxies with deep optical imaging. This study aims to investigate the fraction of star forming galaxies exhibiting faint features to total galaxies. We are analyzing samples of 76 star forming galaxies (NUV < -18) to find merger features from stacked B, R band frames taken at Maidanak 1.5m, McDonald 2.1m telescope and g, r frames from Canada-France-Hawaii Telescope (CFHT) MegaCam archival data. With the fraction, we can expect to know the contribution of mergers on star formation to galaxies.

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