• Title/Summary/Keyword: Polar Region

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Effect of Dietary Fat on Structure and Function of Mammalian Cell Membrane (식이지방이 생체막 구조와 기능에 미치는 영향)

  • Cho, Sung-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.13 no.4
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    • pp.459-468
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    • 1984
  • The currently accepted model of membrane structure proposes a dynamic, asymmetric lipid matrix of phospholipids and cholesterol with globular proteins embedded across the membrane to various degrees. Most phospholipids are in the bilayer arrangement and also closely associated with integral membrane proteins or loosely associated with peripheral proteins. Biological functions of membrane, such as membrane-bound enzyme functions and transport systems, are influenced by the membrane physical properties, which are determined by fatty acid composition of phospholipids, polar head group composition and membrane cholesterol content. Polar and non-polar region of the phospholipid molecule can interact, with changes in the conformation of a membrane-associated protein altering either its catalytic activity or the protein's interaction with other membrane proteins. Mammalian dietary studies attempted to change the lipid composition of a few cell membranes have shown comparisons, using essential fatty acid-deficient diets. In recent years, Clandinin and a few other workers have pioneered the study proving the influence of dietary fat fed in a nutritionally complete diet on composition of phospholipid classes of cell membrane. Modulation caused by diet fat was rapid and reversible in phospholipid fatty acyl composition of membranes of cardiac mitochondria, liver cell, brain synaptosome and lymphocytes. These changes were at the same time, accompanied by variety of membrane associated functions controlled by membrane-bound enzymes, tranporter and receptor proteins. The findings suggest the basic concept of the necessity of dietary fatty acid balance if consistency of optimal membrane structural lipid composition is to be maintained, as well as the overall inadequacy of describing the nutritional-biochemical quality of a dietary fat solely by its content of linoleic acid. Furthermore, they give light on the possible application to clinical and preventive medicine.

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Climatic Characteristics Related with Sedimentary Process in Bransfield Strait, Antarctica (남극 브랜스필드 해협에서의 퇴적과정과 관련된 기후특성)

  • Lee, Bang-Yong;Kwon, Tae-Yong;Lee, Jeong-Soon;Yoon, Ho-Il;Yoon, Young-Jun
    • Journal of the Korean Geophysical Society
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    • v.8 no.4
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    • pp.173-185
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    • 2005
  • This study examines the relationships among sea ice concentration, surface air temperature, surface wind, and SST (Sea Surface Temperature) in Bransfield Strait to understand the climatic characteristics and its related sedimentary process there. In analyses of the monthly data, during the austral autumn (Mar., Apr., and May), the frequency of southeasterlies is correlated positively with the sea ice concentration and negatively with the surface air temperature, whereas that of northwesterlies is reverse. These relationships are explained by the process that the southeasterlies of the cold air from the Antarctic Continent affect the ocean current around Bransfield Strait. And then the ocean current makes the sea ice generated in the Weddell Sea drift into the strait. During the spring (Sep., Oct., and Nov.), sea ice concentration and surface air perature are closely correlated with the frequency of northwesterlies with warm air mass. In the some parts of the northern boundary region, the sea ice concentration in Bransfield Strait is positively correlated with the SST during the autumn and spring. Such relationship may rather propel the sea ice melting in proportion to the sea ice concentration during the autumn.

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Analysis of CHAMP Magnetic Anomalies for Polar Geodynamic Variations

  • Kim Hyung Rae;von Frese Ralph R.B.;Park Chan-Hong;Kim Jeong Woo
    • Korean Journal of Remote Sensing
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    • v.21 no.1
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    • pp.91-98
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    • 2005
  • On board satellite magnetometer measures all possible magnetic components, such as the core and crustal components from the inner Earth, and magnetospheric, ionospheric and' its coupled components from the outer Earth. Due to its dipole and non-dipole features, separation of the respective component from the measurements is most difficult unless the comprehensive knowledge of each field characteristics and the consequent modeling methods are solidly constructed. Especially, regional long wavelength magnetic signals of the crust are strongly masked by the main field and dynamic external field and hence difficult to isolate in the satellite measurements. In particular, the un-modeled effects of the strong auroral external fields and the complicated behavior of the core field near the geomagnetic poles conspire to greatly reduce the crustal magnetic signal-to-noise ratio in the polar region relative to the rest of the Earth. We can, however, use spectral correlation theory to filter the static lithospheric and core field components from the dynamic external field effects that are closely related to the geomagnetic storms affecting ionospheric current disturbances. To help isolate regional lithospheric anomalies from core field components, the correlations between CHAMP magnetic anomalies and the pseudo-magnetic effects inferred from satellite gravity-derived crustal thickness variations can also be exploited, Isolation of long wavelengths resulted from the respective source is the key to understand and improve the models of the external magnetic components as well as of the lower crustal structures. We expect to model the external field variations that might also be affected by a sudden upheaval like tsunami by using our algorithm after isolating any internal field components.

Multiple Node Flip Fast-SSC Decoding Algorithm for Polar Codes Based on Node Reliability

  • Rui, Guo;Pei, Yang;Na, Ying;Lixin, Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.2
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    • pp.658-675
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    • 2022
  • This paper presents a fast-simplified successive cancellation (SC) flipping (Fast-SSC-Flip) decoding algorithm for polar code. Firstly, by researching the probability distribution of the number of error bits in a node caused by channel noise in simplified-SC (SSC) decoder, a measurement criterion of node reliability is proposed. Under the guidance of the criterion, the most unreliable nodes are firstly located, then the unreliable bits are selected for flipping, so as to realize Fast-SSC-Flip decoding algorithm based on node reliability (NR-Fast-SSC-Flip). Secondly, we extended the proposed NR-Fast-SSC-Flip to multiple node (NR-Fast-SSC-Flip-ω) by considering dynamic update to measure node reliability, where ω is the order of flip-nodes set. The extended algorithm can correct the error bits in multiple nodes, and get good performance at medium and high signal-to-noise (SNR) region. Simulation results show that the proposed NR-Fast-SSC-Flip decoder can obtain 0.27dB and 0.17dB gains, respectively, compared with the traditional Fast-SSC-Flip [14] and the newly proposed two-bit-flipping Fast-SSC (Fast-SSC-2Flip-E2) [18] under the same conditions. Compared with the newly proposed partitioned Fast-SSC-Flip (PA-Fast-SSC-Flip) (s=4) [18], the proposed NR-Fast-SSC-Flip-ω (ω=2) decoder can obtain about 0.21dB gain, and the FER performance exceeds the cyclic-redundancy-check (CRC) aided SC-list (CRC-SCL) decoder (L=4).

A Study of Structure Monitoring Applicability of ZigBee Module through Oil Sand Plant Temperature around Canada (캐나다 오일샌드 플랜트 온도 조건을 고려한 구조물 모니터링 통신 모듈 적용성에 관한 연구)

  • Yang, Heekwon;Lee, Chankil;Lee, Bang Yong;Park, Keunbo
    • The KSFM Journal of Fluid Machinery
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    • v.19 no.3
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    • pp.37-42
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    • 2016
  • The demand for wireless technology in plant structure has recently been increasing due to several advantages such as installation cost reduction, easy placement, easy extension and aesthetic benefits. Among the many wireless technologies, ZigBee is one of the most useful for plant structure; a wireless plant networking system can be configured using ZigBee alone. This research proposes a ZigBee to use for extreme cold region and thereby enable integration of wired and wireless plant monitoring systems. In this study, in order to assess the performance of ZigBee measured data by thermocouple were examined based on the results from laboratory tests between existing ZigBee and developed ZigBee. From the experiment results, performance of developed ZigBee in harsh environment can be increased well.

Comparison between Ionospheric and plasmaspheric TECs measured from JASON satellite: plasmaspheric flux

  • Lee, Han-Byul;Jee, Geon-Hwa;Kim, Yong-Ha;Chung, Jong-Kyun
    • Bulletin of the Korean Space Science Society
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    • 2011.04a
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    • pp.27.3-27.3
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    • 2011
  • The plasmasphere is filled with the ions and electron transported mostly from the mid-latitude ionosphere. In the topside ionosphere where the $O^+$ ions are still major ions, the $O^+$ ions are in chemical equilibrium with the $H^+$ ions and exchange their charges with each other's parent atoms with similar rates in both reactions. During the day, the newly produced $H^+$ ions flow upward to fill the plasmasphere while they flow downward and contribute to the maintenance of the ionospheric density at night under the geomagnetically quiet condition. The ionosphere and plasmasphere are coupled by these plasma fluxes and therefore strongly affect each other. In order to study these coupling we utilized the plasma density measurements from JASON satellite. This satellite measures vertical total electron content (TEC) from the ground to the satellite orbit (about 1336 km) and slant TEC from the satellite orbit to much higher GPS satellites by using the on-board dual-frequency altimeter and GPS receiver, respectively. The former measurement can represent the ionospheric TEC while the latter can represent the plasmaspheric TEC in the equatorial region. We compared these data with different seasons, solar activities and local times, and the results will be presented.

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Power Quality Analysis of Wind-Diesel Hybrid Generation System Installation Area (복합발전 풍력-디젤 하이브리드 시스템 설치 지역의 전력품질 분석)

  • An, Hae-Joon;Kim, Hyun-Goo;Kim, Seok-Woo;Ko, Seok-Whan;Jang, Gil-Soo
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.539-541
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    • 2009
  • A severely cold weather condition of King Sejong Station, Antarctica becomes a very severe condition for an installation/operation of wind generation system. When the existing wind generation system works, it may cause a damage and destruction of wind generation system and can bring about big problems in terms of the power quality. Accordingly, it is essential to obtain technologies for the installation and operation of small wind generation system for the polar region's wind generation, and to assess and demonstrate the performance in the severely-cold environment and the polar wind generation system's development, supplementation, alteration. Also, as the available power of King Sejong Station, Antarctica, the diesel generator has been mainly used, and the wind generator has been used in the hybrid form. Wind generation and diesel generation has the different load following control each other. In the wind generation, the generated power very rapidly changes according to the change of the velocity of the wind. On the other hand, the diesel generation shows very gentle change in the velocity of output. Therefore, the study is intended to analyze the 10kw small wind generator-diesel generator's power quality of King Sejong Station, Antarctica, which is the hybrid system installation area.

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Complete genome sequence of a cold-adapted humic acid degrading bacterium Pedobacter sp. PAMC 27299 from the Antarctic seashore (남극 해안으로부터 저온적응 부식산 분해 Pedobacter sp. PAMC 27299의 유전체 서열 해독)

  • Kim, Hye-Jin;Park, Jae Wan;Park, Ha Ju;Kim, Dockyu;Sul, Woo Jun
    • Korean Journal of Microbiology
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    • v.52 no.3
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    • pp.388-390
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    • 2016
  • Pedobacter sp. PAMC 27299 with humic acid cultivated on low temperature was isolated from the moss debris on the coast of the Barton Peninsula of King George Island of the maritime Antarctic region. Here, we present the complete genome sequence of Pedobacter sp. PAMC 27299, which contains 6,147,290 bp with a G+C content of 40.54%. PAMC 27299 may possess cold-adapted humic acid degradation enzymes with implication on global warming.

Genomic Tandem Quadruplication is Associated with Ketoconazole Resistance in Malassezia pachydermatis

  • Kim, Minchul;Cho, Yong-Joon;Park, Minji;Choi, Yoojeong;Hwang, Sun Young;Jung, Won Hee
    • Journal of Microbiology and Biotechnology
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    • v.28 no.11
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    • pp.1937-1945
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    • 2018
  • Malassezia pachydermatis is a commensal yeast found on the skin of dogs. However, M. pachydermatis is also considered an opportunistic pathogen and is associated with various canine skin diseases including otitis externa and atopic dermatitis, which usually require treatment using an azole antifungal drug, such as ketoconazole. In this study, we isolated a ketoconazole-resistant strain of M. pachydermatis, designated "KCTC 27587," from the external ear canal of a dog with otitis externa and analyzed its resistance mechanism. To understand the mechanism underlying ketoconazole resistance of the clinical isolate M. pachydermatis KCTC 27587, the whole genome of the yeast was sequenced using the PacBio platform and was compared with M. pachydermatis type strain CBS 1879. We found that a ~84-kb region in chromosome 4 of M. pachydermatis KCTC 27587 was tandemly quadruplicated. The quadruplicated region contains 52 protein coding genes, including the homologs of ERG4 and ERG11, whose overexpression is known to be associated with azole resistance. Our data suggest that the quadruplication of the ~84-kb region may be the cause of the ketoconazole resistance in M. pachydermatis KCTC 27587.

BIDIRECTIONAL FACTOR OF WATER LEAVING RADIANCE FOR GOCI

  • Han, Hee-Jeong;Ahn, Yu-Hwan;Ryu, Joo-Hyung
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.79-81
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    • 2006
  • Geostationary ocean satellite, unlike other sun-synchronous polar-orbit satellites, will be able to take a picture of a large region several times a day (almost with every one hour interval). For geostationary satellite, the target region is fixed though the location of sun is changed always. Thus, the ocean signal of a given target point is largely dependent on time. In other words, the ocean signal detected by geostationary satellite sensor must translate to the signal of target when both sun and satellite are located in nadir, using another correction model. This correction is performed with a standardization of signal throughout relative geometric relationship among satellite - sun - target points. One signal value of a selected pixel point of the target region of Geostationary Ocean Colour Imager (GOCI) would be set up as a standard, and the ratio of all remained pixel point can be calculated. This relative ratio called bidirectional factor, the result of modelling of spatiotemporal variation of bidirectional factor is shown.

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