• Title/Summary/Keyword: Guard Ring

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Ship Collision Avoidance Support Model in Close Quarters Situation (II) (근접상황 선박충돌회피지원모델에 관한 연구(II))

  • Yang Hyoung-Seon;Yea Byeong-Deok
    • Journal of Navigation and Port Research
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    • v.29 no.10 s.106
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    • pp.827-832
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    • 2005
  • In this paper, as a fundamental study of ship collision avoidance supporting system in close quarters situation, we propose ship collision avoidance support model for decreasing ship collision accidents those have occurred due to navigator's unsuitable maneuvering in close encounter. This model will effectively support maneuvering for collision avoidance through displaying the feasible area and the method of collision avoidance using own ship's turning characteristic about action of target ship's keeping course and velocity.

Ship Collision Avoidance Support Model in Close Quarters Situation(II) (근접상황 선박충돌회피지원모델에 관한 연구(II))

  • Yang, Hyoung-Seon;Yea, Byeong-Deok
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.119-124
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    • 2005
  • In this paper, as a fundamental study of ship collision avoidance supporting system in close quarters situation, we propose ship collision avoidance support model for decreasing ship collision accidents those have occurred due to navigator's unsuitable maneuvering in close encounter. This model will effectively support maneuvering for collision avoidance through displaying the feasible area and the method of collision avoidance using own ship's turning characteristic about target ship's keeping course and velocity maneuvering actions.

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The Evaluation of Multiplane-Parallel Chamber Using Crystal Plate as Ionization Medium for Therapeutic Radiation Beams

  • Young W. Vahc;Park, Kyung R.;Kim, Sookil;Chul W. Joh;Kim, Tae H.
    • Progress in Medical Physics
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    • v.9 no.1
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    • pp.29-35
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    • 1998
  • There has been necessity of an air free ionization chamber using the gold-crystal-aluminium plates, henceforth called the crystal chamber. The crystal chamber formed of parallel plates is very small in size and has more response for absorbed dose of therapeutic radiation beams. The gold plate on the crystal facing the photon and electron beam acts as an intensifier of signals and crystal plate as an ionization medium respectively. Both the copper guard ring and the aluminum collecting electrode are connected to an electrometer. Using high energy photon (6, 15 MV) and electron (9, 12, 15, 18 MeV) beams, the responses of the crystal chamber are evaluated against a PTW Farmer-type chamber at a field size of 10${\times}$10cm$^2$ and 100 cm SSD. The responses of crystal chamber for therapeutic radiation electron and photon beams are greater in magnitude by several order than Farmer. The crystal chamber has good linearity without correction factor C$\_$t,p/ with respect to the signals, a reading reproduction with good accuracy and precision less than 0.5%, and has other useful functions in measuring radiation beams.

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Revisiting Use of Growth Factors in Myelodysplastic Syndromes

  • Newman, Kam;Maness-Harris, Lori;El-Hemaidi, Ihab;Akhtari, Mojtaba
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1081-1091
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    • 2012
  • Myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal hematologic neoplasms characterized by morphologic dysplasia, aberrant hematopoiesis and peripheral blood refractory cytopenias. MDS is recognized to be associated with an increased risk of symptomatic anemia, infectious complications and bleeding diathesis, as well as a risk of progression to acute myeloid leukemia, particularly in patients with a high IPSS score. The advent of use of hematopoietic growth factors such as granulocyte colony-stimulating factor (G-CSF) and recombinant erythropoietin (EPO) has improved symptoms in MDS patients in addition to some data that suggest there might be an improvement in survival. G-CSF is an effective therapeutic option in MDS patients, and it should be considered for the management of refractory symptomatic cytopenias. G-CSF and EPO in combination can improve outcomes in appropriate MDS patients such as those with lower-risk MDS and refractory anemia with ring sideroblasts (RARS). This article reviews use of growth factors for lower-risk MDS patients, and examines the data for G-CSF, EPO and thrombopietic growth factors (TPO) that are available or being developed as therapeutic modalities for this challenging disease.

A Study on the Characteristics Comparison of Single Chip and Two Chip Transceiver for the Fiber Optic Modules (광모듈용 단일 칩 및 2 칩 트랜시버의 특성비교 연구)

  • Chai Sang-Hoon;Jung Hyun-Chae
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.5 s.347
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    • pp.48-53
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    • 2006
  • This paper describes the electrical characteristics of monolithic optical transceiver circuitry being used in the fiber optic modules. It has been designed and fabricated, and compared with two chips version transceiver when operates at 155.52 Mbps data rates. To avoid noise and interference between transmitter and receiver on one chip, layout techniques such as special placement, power supply separation, guard ring, and protection wall were used in the design. To compare the two kind of fiber optic modules using each chip, single chip version has similar properties to two chip version in the electrical characteristics as noise and others.

Effect of Channel Variation on Switching Characteristics of LDMOSFET

  • Lee, Chan-Soo;Cui, Zhi-Yuan;Kim, Kyoung-Won
    • Journal of Semiconductor Engineering
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    • v.3 no.2
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    • pp.161-167
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    • 2022
  • Electrical characteristics of LDMOS power device with LDD(Lightly Doped Drain) structure is studied with variation of the region of channel and LDD. The channel in LDMOSFET encloses a junction-type source and is believed to be an important parameter for determining the circuit operation of CMOS inverter. Two-dimensional TCAD MEDICI simulation is used to study hot-carrier effect, on-resistance Ron, breakdown voltage, and transient switching characteristic. The voltage-transfer characteristics and on-off switching properties are studied as a function of the channel length and doping levels. The digital logic levels of the output and input voltages are analyzed from the transfer curves and circuit operation. Study indicates that drain current significantly depends on the channel length rather than the LDD region, while the switching transient time is almost independent of the channel length. The high and low logic levels of the input voltage showed a strong dependency on the channel length, while the lateral substrate resistance from a latch-up path in the CMOS inverter was comparable to that of a typical CMOS inverter with a guard ring.

Design of a Single Chip CMOS Transceiver for the Fiber Optic Modules (광통신 모듈용 단일칩 CMOS 트랜시버의 설계)

  • 채상훈;김태련;권광호
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.2
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    • pp.1-8
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    • 2004
  • This paper describes the design of monolithic optical transceiver circuitry being used as a part of the fiber optic modules. It has been designed in 0.6 ${\mu}{\textrm}{m}$ 2-poly 3 metal silicon CMOS analog technology and operates at 155.52 Mbps(STM-1) data rates. It drives laser diode to transmit intensity modulated optical signal according to 155.52 Mbps electrical data from system. Also, it receives 155.52 Mbps optical data that transmitted from other systems and converts it to electrical data using photo diode and amplifier. To avoid noise and interference between transmitter and receiver on one chip, layout techniques such as special placement, power supply separation, guard ring, and protection wall were used in the design. The die area is 4 ${\times}$ 4 $\textrm{mm}^2$ and the estimated power dissipation is less than 900 ㎽ with a single 5 V supply.

Implementation of a Single Chip CMOS Transceiver for the Fiber Optic Modules (광통신 모듈용 단일 칩 CMOS트랜시버의 구현)

  • 채상훈;김태련
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.9
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    • pp.11-17
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    • 2004
  • This paper describes the implementation of monolithic optical transceiver circuitry being used as a part of the fiber optic modules. It has been fabricated in 0.6 ${\mu}{\textrm}{m}$ 2-poly 3-metal silicon CMOS analog technology and operates at 155.52 Mbps(STM-1) data rates. It drives laser diode to transmit intensity modulated optical signal according to 155.52 Mbps electrical data from system. Also, it receives 155.52 Mbps optical data that transmitted from other systems and converts it to electrical data using photo diode and amplifier. To avoid noise and interference between transmitter and receiver on one chip, layout techniques such as special placement, power supply separation, guard ring, and protection wall were used in the design. The die area is 4 ${\times}$ 4 $\textrm{mm}^2$, and it has 32.3 ps rms and 335.9 ps peak to peak jitter on loopback testing. the measured power dissipation of whole chip is 1.15 W(230 mW) with a single 5 V supply.

Silicon Substrate Coupling Modeling, Analysis, and Substrate Parameter Extraction Method for RF Circuit Design (RF 회로 설계를 위한 실리콘 기판 커플링 모델링, 해석 및 기판 파라미터 추출)

  • Jin, Woo-Jin;Eo, Yung-Seon;Shim, Jong-In
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.12
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    • pp.49-57
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    • 2001
  • In this paper, equivalent circuit model and novel model parameter extraction method of a silicon(Si) substrate are presented. Substrate coupling through Si-substrate is quantitatively investigated by analyzing equivalent circuit with operating frequency and characteristic frequencies (i.e., pole and zero frequency) of a system. For the experimental verification of the equivalent circuit and parameter extraction method, test patterns are designed and fabricated in standard CMOS technology with various isolation distances, substrate resistivity, and guard-ring structures. Then, these are measured in l00MHz-20GHz frequency range by using vector network analyzer. It is shown that the equivalent-circuit-based HSPICE simulation results using extracted parameters have excellent agreement with the experimental results. Thus, the proposed equivalent circuit and parameter extraction methodology can be usefully employed in mixed-signal circuit design and verification of a circuit performance.

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A Study on Development of Ship Collision Avoidance Support Program (선박충돌회피지원프로그램 개발에 관한 연구)

  • Yang Hyoung-Seon;Jeong Dae-Deuk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.12 no.1 s.24
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    • pp.47-52
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    • 2006
  • Recently, ship collision accidents account for $20%{\sim}34%$ of domestic marine accidents, also have increased continually. In this paper, therefore we propose the development of Ship Collision A voidance Support program for decreasing ship collision accidents. This program has been developed on the basis of CCAS-Model. A CCAS-Model has ship's maneuvering performance and has been studied for the propose of supporting to avoid ship collision in close quarters. Besides. the program will effectively support maneuvering for collision avoidance through display of the feasible area and the method of collision avoidance using own ship's turning characteristic about action of target ship's keeping course and velocity in various encounter.

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