• Title/Summary/Keyword: Satellite cell

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A spindle cell squamous cell carcinoma on the cheek presenting with in-transit metastases and a satellite lesion

  • Lee, Eui-Tae
    • Archives of Craniofacial Surgery
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    • v.21 no.1
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    • pp.58-63
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    • 2020
  • Spindle cell squamous cell carcinoma (SpSCC) is a biphasic tumor composed of squamous cell epithelial and spindle cell mesenchymal components, both of which are malignant. Cutaneous SpSCC can cause diagnostic and therapeutic difficulties because of its rarity, heterogeneity, morphological similarity to other cutaneous spindle cell neoplasms, and uncertain pathogenesis and prognosis, particularly when the squamous cell carcinoma component is minimal or missing. Intransit metastasis and satellite lesion (satellitosis) constitute a spectrum of non-nodal regional metastases. Here the author reports the first known case of cutaneous SpSCC presenting with intransit metastases and a satellite lesion, which were exceptionally aggressive. A 77-year-old female patient presented with a 3×3×0.5 cm mass on her right cheek. Despite wide excision and postoperative radiation, the patient resulted in local recurrence and multiple distant metastases within 3 months. If many high-risk factors-particularly satellitosis and in-transit metastases are observed in a tumor with epithelial to mesenchymal transition, then further wide excision and adjuvant chemoradiation should be considered early in the treatment process. A multidisciplinary approach could be the key to cure the most aggressive malignancies of the skin, as in other organs.

QPSK Modem Design of Satellite Air-defence Warning System (위성 전군방공경보체계 QPSK 모뎀 설계)

  • Kim, Younghun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.18 no.6
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    • pp.755-761
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    • 2015
  • Satellite Air-defence Warning System receives the aircraft/ballistic track information and air defense control command obtained from Master Control & Reporting Center (MCRC) and Air Missile Defence Cell (AMD Cell) Systems. It consists of terminal and control system to propagate track information and air defense control command control via the military satellite communications. In this paper, there were described track information, air defense control command, the frame structure of modem to transmit a voice information and modulation/demodulator design, network synchronization methods via the satellite network.

A Study on Mass Reduction in the Conceptual Design of Solar Array with Commercial Solar Cells for Small SAR Satellites (상용 태양전지 셀을 이용한 소형 SAR 위성의 태양전지 어레이 개념설계 및 경량화 연구)

  • Kim, Tae-Deuk
    • Journal of the Korean Solar Energy Society
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    • v.37 no.5
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    • pp.49-63
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    • 2017
  • Solar cells have widely been utilized for a satellite to convert sunlight energy into electricity in space. Many different types of solar cells appropriate for each satellite program are available in current markets, which enables us to construct a solar array light and small often required from a low Earth orbit (LEO) synthetic aperture radar (SAR) satellite. Thus, it is important to choose a proper solar cell satisfying the requirements of mass and size for the solar array. In this article, we have surveyed typical suppliers and have discussed some characteristics of solar cells. Conceptual design examples of the solar array for LEO SAR satellites using several types of solar cells have been performed to show the pros and cons of solar cells by comparison of the total mass and size necessary for the solar array.

GFAP IMMUNOREACTIVITY IN TRIGEMINAL GANGLION SATELLITE CELLS AFTER PULP EXPOSURE IN RAT (흰쥐에서 치수노출 후 삼차신경절의 신경절아교세포에서 GFAP-IR의 변화)

  • Kim, Heung-Jung;Moon, Joo-Hoon
    • Restorative Dentistry and Endodontics
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    • v.22 no.2
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    • pp.782-791
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    • 1997
  • Glial fibrillary acidic protein(GFAP) are a group of intermediate filaments that are distributed in the cytoplasm of many type of glial cells. The purpose of this study was to determine change of GFAP immunoreactivity(GFAP-IR) in rat trigeminal ganglion satellite cells in response to pulp exposure. The immunohistochemistry was carried out using the avidinbiotin-peroxidase complex(ABC) method and subsequently stained with AEC(3-aminoethyl-9-carbasol). 1. Contol group; Central root astrocytes had strong GFAP-IR, but ganglion satellite cells occasionlly had GFAP-IR. This reaction patterns of ganglion satellite cells was not concenturated in any specific region of trigeminal ganglion. 2. Three day pulp exposure group; There was a highly GFAP-IR in satellite cells of trigeminal ganglion in maxillary region. GFAP-IR in neighboring mandibular and ophthalmic regions was less intense compared to maxillary region. 3. Seven day pulp exposure group; In this group, GFAP-IR that was increased compared to control group was seen in the maxillary region. But GFAP-IR was less intense compared to three day pulp exposure group. These results suggest that GFAP in satellite cell increase in specific region of trigeminal ganglion after pulp exposure and offer useful tool in trigeminal pain research.

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Comparison of Gene Expression Levels of Porcine Satellite Cells from Postnatal Muscle Tissue during Differentiation

  • Jeong, Jin Young;Kim, Jang Mi;Rajesh, Ramanna Valmiki;Suresh, Sekar;Jang, Gul Won;Lee, Kyung-Tai;Kim, Tae Hun;Park, Mina;Jeong, Hak Jae;Kim, Kyung Woon;Cho, Yong Min;Lee, Hyun-Jeong
    • Reproductive and Developmental Biology
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    • v.37 no.4
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    • pp.219-224
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    • 2013
  • Muscular satellite cell (SC), which is stem cell of postnatal pig, is an important for study of differentiation into adipogenesis, myogenesis, and osteoblastogenesis. In this study, we isolated and examined from pig muscle tissue to determine capacity in proliferate, differentiate, and expression of various genes. Porcine satellite cells (PSC) were isolated from semimembranosus (SM) muscles of 90~100 days old pigs according to standard conditions. The cell proliferation increased in multi-potent cell by Masson's, oil red O, and Alizarin red staining respectively. We performed the expression levels of differentiation related genes using real-time PCR. We found that the differentiation into adipocyte increased expression levels of both fatty acid binding protein 4 (FABP4) and peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) genes (p<0.01). Myocyte increased the expression levels of the myosin heavy chain (MHC), myogenic factor 5 (Myf5), myogenic regulatory factor (MyoD), and Myogenic factor 4 (myogenin) (p<0.01). Osteoblast increased the expression levels of alkaline phosphatase (ALP) (p<0.01). Finally, porcine satellite cells were induced to differentiate towards adipogenic, myogenic, and osteoblastogenic lineages. Our results suggest that muscle satellite cell in porcine may influence cell fate. Understanding the progression of PSC may lead to improved strategies for augmenting meat quality.

Configuration and Characteristics of Fine Sun Sensor for Satellite (위성용 고정밀 태양센서 구성 및 특성)

  • Kim, Yong-Bok;Pank, Keun-Joo;Choi, Hong-Taek
    • Aerospace Engineering and Technology
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    • v.10 no.2
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    • pp.87-93
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    • 2011
  • FSSA(Fine Sun Sensor Assembly) is the important sensor for satellite attitude control. FSSA measures the direction of the sun's rays and determines whether the satellite is in the eclipse or not. FSSA for GEO Satellite is also used to acquire the attitude error information in the attitude control reference frame and acquire the Sun direction during transfer orbit or mission Process. This paper shows the configuration of Fine Sun Sensor for LEO and GEO Satellite and their principle of operation that angle measurement is obtained by using the transfer function which is the ratio of the difference between output currents of Solar Cell to the sum of all output currents.

The channel coding algorithm for the ATM cell QoS improvement in statellite B-ISDN/ATM network (위성 B-ISDN/ATM 망에서 ATM 셀 전송성능 개선을 위한 채널코딩 알고리즘)

  • 김신재;김병균;최형진
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.5
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    • pp.1083-1096
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    • 1997
  • To implement satellite B-ISDN/ATM network, it needs to gurantee reliable transport via satelite in the poor BER environment. So, it requires to use channel coding (FEC:Forward Error Correction) schemes for improvement of BER performance, but these coding effects evoke burst errors and degradation of the QoS. Therefore we have to investigate new algorithm that compensates these weaknesses. We consider convolutional coding and concatenated coding among FEC schemes as FEC for satellite transmission and choose different compensational algorithm by the error characteristics of the using type of FEC. In using concatenated coding, this paper proposes the satellite system structure for interconnection to the terrestrial network and proposes the channel coding algorithm for improvement of transmission performances. We execute performance evaluation of the proposed algorithm by computer simulation. In detail, we propose 4 types of application ATM cell to the block coding(Reed-Solomon) and propose the new 55 byte ATM cell that enforces the error correction capability of cell header by the BCH coding. Then we propose the outer interleaverand the cell unit interleaver that evoke maximum coding effect of BCH code.

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Analysis of Magnetic Dipole Moment for a 300-W Solar-Cell Array

  • Shin, Goo-Hwan;Kim, Dong-Guk;Kwon, Se-Jin;Lee, Hu-Seung
    • Journal of Astronomy and Space Sciences
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    • v.36 no.3
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    • pp.181-186
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    • 2019
  • The attitude information of spacecraft can be obtained by the sensors attached to it using a star tracker, three-axis magnetometer, three-axis gyroscope, and a global positioning signal receiver. By using these sensors, the spacecraft can be maneuvered by actuators that generate torques. In particular, electromagnetic-torque bars can be used for attitude control and as a momentum-canceling instrument. The spacecraft momentum can be created by the current through the electrical circuits and coils. Thus, the current around the electromagnetic-torque bars is a critical factor for precisely controlling the spacecraft. In connection with these concerns, a solar-cell array can be considered to prevent generation of a magnetic dipole moment because the solar-cell array can introduce a large amount of current through the electrical wires. The maximum value of a magnetic dipole moment that cannot affect precise control is $0.25A{\cdot}m^2$, which takes into account the current that flows through the reaction-wheel assembly and the magnetic-torque current. In this study, we designed a 300-W solar cell array and presented an optimal wire-routing method to minimize the magnetic dipole moment for space applications. We verified our proposed method by simulation.

Predictive Connection Admission Control for Broadband ATM Satellite Systems

  • Yeong Min Jang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.6A
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    • pp.927-934
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    • 2000
  • In this paper, we propose a predictive(transient) connection admission control(CAC) scheme for satellite systems that supports on-board packet switching of multimedia traffic with predefined quality of service(QoS) requirements. The CAC scheme incorporates the unique characteristics of satellite systems, e.g. large propagation delays, no onboard buffer, and low computational requirement. The CAC scheme requires the estimation of the On-Off traffic characteristics ($\lambda$, $\mu$) of the traffic sources. These estimated values are used to predict the transient cell loss ratio at each downlink. In case the QoS requirements are not met the proposed CAC scheme rejects the new connection. The numerical results obtained suggest that the proposed scheme is an excellent candidate for real time burst and cell level connection prediction and control in broadband on-board satellite networks.

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Energy Balance Analysis of Electrical Power System for Communication Satellite (통신방송위성 전력시스템의 Energy Balance 해석)

  • Choi Jae-dong;Koo Cheol-hea
    • Proceedings of the KIPE Conference
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    • 2001.07a
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    • pp.81-84
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    • 2001
  • In the power system of a satellite, solar array and a battery have directly impact on the life time of the satellite, and their stable operation is decided by whether their states are in the steady state operation or not. In this study, solar array capacity and battery characteristics of proposed communication satellite are designed and simulation is conducted according to the operation mode. Each operation mode is classified as the normal and worst case modes, respectively. The normal mode is analyzed under daylight and the eclipse with the EHT burn, and the worst case modes which have solar cell circuit failure, and battery cell failure are analyzed too.

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