• Title/Summary/Keyword: Mask design

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Comparison of Characteristics of Gamma-Ray Imager Based on Coded Aperture by Varying the Thickness of the BGO Scintillator

  • Seoryeong Park;Mark D. Hammig;Manhee Jeong
    • Journal of Radiation Protection and Research
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    • v.47 no.4
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    • pp.214-225
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    • 2022
  • Background: The conventional cerium-doped Gd2Al2Ga3O12 (GAGG(Ce)) scintillator-based gamma-ray imager has a bulky detector, which can lead to incorrect positioning of the gammaray source if the shielding against background radiation is not appropriately designed. In addition, portability is important in complex environments such as inside nuclear power plants, yet existing gamma-ray imager based on a tungsten mask tends to be weighty and therefore difficult to handle. Motivated by the need to develop a system that is not sensitive to background radiation and is portable, we changed the material of the scintillator and the coded aperture. Materials and Methods: The existing GAGG(Ce) was replaced with Bi4Ge3O12 (BGO), a scintillator with high gamma-ray detection efficiency but low energy resolution, and replaced the tungsten (W) used in the existing coded aperture with lead (Pb). Each BGO scintillator is pixelated with 144 elements (12 × 12), and each pixel has an area of 4 mm × 4 mm and the scintillator thickness ranges from 5 to 20 mm (5, 10, and 20 mm). A coded aperture consisting of Pb with a thickness of 20 mm was applied to the BGO scintillators of all thicknesses. Results and Discussion: Spectroscopic characterization, imaging performance, and image quality evaluation revealed the 10 mm-thick BGO scintillators enabled the portable gamma-ray imager to deliver optimal performance. Although its performance is slightly inferior to that of existing GAGG(Ce)-based gamma-ray imager, the results confirmed that the manufacturing cost and the system's overall weight can be reduced. Conclusion: Despite the spectral characteristics, imaging system performance, and image quality is slightly lower than that of GAGG(Ce), the results show that BGO scintillators are preferable for gamma-ray imaging systems in terms of cost and ease of deployment, and the proposed design is well worth applying to systems intended for use in areas that do not require high precision.

Effects of Respiratory Infectious Disease Simulation-based Education using Standardized Patient for Nursing Student's of the Knowledge, Clinical Nursing Competency (표준화환자를 이용한 호흡기감염 시뮬레이션 교육이 간호대학생의 지식, 임상수행능력에 미치는 효과)

  • Jung Hur;Yeong Ju Yoon
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.3
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    • pp.435-442
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    • 2023
  • The purpose of this study is to analyze the effects of simulation education using standardized patients on respiratory infectious disease knowledge and clinical performance of nursing students. A single-group before-and-after design for the nursing of infectious respiratory patients using standardized patients from March 2 to June 15, 2020, targeting 112 senior nursing students. Respiratory infectious disease education program 'knowledge of lung infectious diseases', 'hand washing', 'wearing a mask', 'encouraging patients and caregivers to wear masks', 'intravenous injection', '3-way injection', 'surgical aseptic technique', 'disinfecting medical devices' , 'contaminated linen management', 'infected person management manual', etc., and 10 educational tasks were performed, and consisted of lectures, technical training, simulation using standardized patients, and debriefing. After simulation education using standardized patients, students' knowledge and clinical performance skills on respiratory infectious diseases showed significant improvement, and it was expected that it could be used for various infection control practices.

Design of spectrum spreading technique applied to DVB-S2

  • Kim, Pan-Soo;Chang, Dae-Ig;Lee, Ho-Jin
    • Journal of Satellite, Information and Communications
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    • v.2 no.2
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    • pp.22-28
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    • 2007
  • Spectrum spreading, in its general form, can be conceived as an artificial expansion of the signal bandwidth with respect to the minimum Nyquist band required to transmit the desired information. Spreading can be functional to several objectives, including resilience to interference and jammers and reduction of power spectral density levels. In the paper, signal spreading is manly used for increasing the received energy, thus satisfying link budget constraints, for terminals with low aperture antennas, without increasing the transmitted EIRP. As a matter of fact, in many mobile scenarios, even when MODCOD configurations with very low spectral efficiency (i.e. QPSK-1/4) in DVB-S2 standard, are used, the link budget cannot be closed. Spectrum spreading has been recently proposed as a technique to improve system performance without introducing additional MODCOD configurations under the constraint of fixed power spectrum density level at the transmitter side. To this aim, the design of spectrum spreading techniques shall keep into consideration requirements such as spectrum mask, physical layer performance, link budget, hardware reuse, robustness, complexity, and backward compliance with existing commercial equipments. The proposed implementation allows to fully reuse the standard DVB-S2 circuitry and is inserted as an 'inner layer' in the standard DVB-S2 chain.

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Design and Construction of Detector Module for UFFO Burst Alert & Trigger Telescope

  • Jung, Aera;Ahmad, Salleh;Barrillon, Pierre;Brandt, Soren;Budtz-Jorgensen, Carl;Castro-Tirado, Alberto J.;Chen, Pisin;Choi, Ji Nyeong;Choi, Yeon Ju;Connell, Paul;Dagoret-Campagne, Sylvie;Eyles, Christopher;Grossan, Bruce;Huang, Ming-Huey A.;Jeong, Soomin;Kim, Ji Eun;Kim, Min Bin;Kim, Sug-Whan;Kim, Ye Won;Krasnov, A.S.;Lee, Jik;Lim, Heuijin;Linder, Eric V.;Liu, T.C.;Lund, Niels;Min, Kyung Wook;Na, Go Woon;Nam, Ji Woo;Panasyuk, Mikhile I.;Park, Il Hung;Ripa, Jakub.;Reglero, Victor;Rodrigo, Juana M.;Smoot, George.F.;Suh, Jung Eun;Svertilov, Sergei.;Vedenkin, Nikolay;Wang, Min-Zu;Yashin, Ivan
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.207.1-207.1
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    • 2012
  • One of the key aspects of the upcoming Ultra-Fast Observatory (UFFO) Pathfinder for Gamma-Ray Bursts(GRBs) identification will be the UFFO Burst Alert & Trigger Telescope(UBAT), based on a novel space telescope technique. The UBAT consists of coded mask, hopper, and detector module(DM). The UBAT DM consists of YSO crystal arrays, multi-anode photo mulipliers, and readout electronics. We will present the design and construction of the UBAT DM, and the response of the UBAT DM to X-ray sources.

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Simulation Study of a Large Area CMOS Image Sensor for X-ray DR Detector with Separate ROICs (센서-회로 분리형 엑스선 DR 검출기를 위한 대면적 CMOS 영상센서 모사 연구)

  • Kim, Myung Soo;Kim, Hyoungtak;Kang, Dong-uk;Yoo, Hyun Jun;Cho, Minsik;Lee, Dae Hee;Bae, Jun Hyung;Kim, Jongyul;Kim, Hyunduk;Cho, Gyuseong
    • Journal of Radiation Industry
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    • v.6 no.1
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    • pp.31-40
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    • 2012
  • There are two methods to fabricate the readout electronic to a large-area CMOS image sensor (LACIS). One is to design and manufacture the sensor part and signal processing electronics in a single chip and the other is to integrate both parts with bump bonding or wire bonding after manufacturing both parts separately. The latter method has an advantage of the high yield because the optimized and specialized fabrication process can be chosen in designing and manufacturing each part. In this paper, LACIS chip, that is optimized design for the latter method of fabrication, is presented. The LACIS chip consists of a 3-TR pixel photodiode array, row driver (or called as a gate driver) circuit, and bonding pads to the external readout ICs. Among 4 types of the photodiode structure available in a standard CMOS process, $N_{photo}/P_{epi}$ type photodiode showed the highest quantum efficiency in the simulation study, though it requires one additional mask to control the doping concentration of $N_{photo}$ layer. The optimized channel widths and lengths of 3 pixel transistors are also determined by simulation. The select transistor is not significantly affected by channel length and width. But source follower transistor is strongly influenced by length and width. In row driver, to reduce signal time delay by high capacitance at output node, three stage inverter drivers are used. And channel width of the inverter driver increases gradually in each step. The sensor has very long metal wire that is about 170 mm. The repeater consisted of inverters is applied proper amount of pixel rows. It can help to reduce the long metal-line delay.

Design of Zero-Layer FTP Memory IP (PMIC용 Zero Layer FTP Memory IP 설계)

  • Ha, Yoongyu;Jin, Hongzhou;Ha, Panbong;Kim, Younghee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.6
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    • pp.742-750
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    • 2018
  • In this paper, in order to enable zero-layer FTP cell using only 5V MOS devices on the basis of $0.13{\mu}m$ BCD process, the tunnel oxide thickness is used as the gate oxide thickness of $125{\AA}$ of the 5V MOS device at 82A. The HDNW layer, which is the default in the BCD process, is used. Thus, the proposed zero layer FTP cell does not require the addition of tunnel oxide and DNW mask. Also, from the viewpoint of memory IP design, a single memory structure which is used only for trimming analog circuit of PMIC chip is used instead of the dual memory structure dividing into designer memory area and user memory area. The start-up circuit of the BGR (Bandgap Reference Voltage) generator circuit is designed to operate in the voltage range of 1.8V to 5.5V. On the other hand, when the 64-bit FTP memory IP is powered on, the internal read signal is designed to maintain the initial read data at 00H. The layout size of the 64-bit FTP IP designed using the $0.13-{\mu}m$ Magnachip process .is $485.21{\mu}m{\times}440.665{\mu}m$($=0.214mm^2$).

Design of CFL Linearisation Chip for the Mobile Radio Using Ultra-Narrowband Digital Modulation (디지털 초협대역 단말기용 CFL 선형화 칩 설계)

  • Chong Young-Jun;Kang Min-Soo;Yoo Sung-Jin;Chung Tae-Jin;Oh Seung-Hyeub
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.7 s.98
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    • pp.671-680
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    • 2005
  • The CFL linearisation chip which is one of key devices in ultra-narrowband mobile radio transmitter using CQPSK digital modulation method is designed and implemented with $0.35{\mu}m$ CMOS technology. The reduced size and low cost of transmitter are available by the use of direct-conversion and CFL ASIC chip, which improve the power effi챠ency and linearity of transmitting path. In addition, low power operation is possible through CMOS technology The performance test results of transmitter show -25 dBc improvement of IMD level at the 3 kHz frequency offset and then satisfy FCC 47 CFR 90.210 E emission mask in the operation of CFL ASIC chip. At that time, the transmitting power is about PEP(Peak-to-Envelope Power) 5 W. The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

Design for Access Control System based on Voice Recognition for Infectious Disease Prevention (전염성 확산 차단을 위한 음성인식 기반의 출입통제시스템 설계)

  • Mun, Hyung-Jin;Han, Kun-Hee
    • Journal of the Korea Convergence Society
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    • v.11 no.7
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    • pp.19-24
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    • 2020
  • WHO declared a global pandemic on March 11th for Corona 19. However, there is a situation where you have to go to building for face-to-face education or seminars for economic and social activities. The first check method of COVID-19 infection is to measure body temperature, so the primary entrance and exit is blocked for near-field body temperature measurement. However, since it is troublesome to check directly, thermal camera is installed at the entrance of the building, and body temperature is measured indirectly using the infrared camera to control access. In case of middle and high schools, universities, and lifelong education center, we need a system that is possible to interoperate with attendance checks and automatically recognizes whether to wear masks and can authenticate students. We proposed the system that is to confirm whether to wear a mask with a camera that is embedded in a smart mirror, and that authenticates the user through voice recognition of the user who wants to enter the building by using voice recognition technology and determines whether to enter them or not. The proposed system can check attendance if it is linked with near-field temperature measurement and attendance check APP of student's smart phone.

고대(古代) Egypt 복식(服飾)에 나타난 상징성(象徵性) - Tutankhamen 왕조(王朝)를 중심으로 -

  • Jeong, Heung-Suk
    • Journal of the Korean Society of Costume
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    • v.6
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    • pp.121-143
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    • 1982
  • Many studies have done on Egyptian Clothing because its unique characteristic culture. However, I was facinated by the exhibitions of Tutankhamen burial treasures which were shown in San Francisco and New York in 1978 and 1979. I found out myself that there are several interesting aspects of clothing to compare 18th dynasty king, Tutankhamun and other dynasties in Egyptian culture. Therefore, I tryed to analized the Egyptian clothing including accessaries with theigr symbols durin 18th dynasty King, Tutankhamun. The most of people were shocked and amazed when they toured the exhibition of Tutankhamun articles which were the most incredible burial treasures in existence today. The body of the King has been embalmed, bandaged and fitted in eight layers of coffins with pure gold mask to represent the god Osiris. Among eight layers of coffins, one is pure solid gold in mummiform, two of mummiforms are made of compact wood covered with sheets of gold and inlaid with multi-colored glass-paste and semi-precious stones. The Egyptian belived that the soul continued to exist throughout eternity if it had passed on examination of its deeds on earth at a "Last Judgement" presided over by Osiris. They also believed that the mummified body could exist in the tomb as a habitation that the soul could revisited. Thus a proper burial was vital for a full existence in the hereafter. They buried dead person in the sealed vault of the tomb with some of the possessions he had used during his life time, such as his furniture, clothing and jewels. In this studies, I've tried to research to various clothings, and accessories with their symbols used during 18th dynasty king, Tutankhamun. The studies are shown as: I) Clothings of Tutankhamun dynasity of Kalasiris, Sheath skirt. Gala skirt, Loin skirt, Hike and Dalmatic. The Dalmatic was first seen in this dynasty. Probably the Roman Christian borrowed the Dalmatica from Egyptian Dalmatic. No where has the same design at the period. II) Egyptian of 18th dynasty Tutankhamun wore big headdress, broad collar necklace passium, pendants, armlets, rings and earrings with very beautiful, exquisite handcraft. They seem the first people who wore earrings in Egyptian history. III) The symbols of decorated items vulture, lotus...Upper Egypt Uraeus, papyrus...Lower Egypt scaravaeus, Nile Riber...rebirth man(Ankh), +...eternal life solar disc, gold...sun ostrich-feather...nobleness God, Horus' eye...protection against enemy IV) Also Egyptian prefered the straight line and a right angle which were the basic principles of architectural arrangement.

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Design of Bias Circuit for Measuring the Multi-channel ISFET (다채널 ISFET 측정용 단일 바이어스 회로의 설계)

  • Cho, Byung-Woog;Kim, Young-Jin;Kim, Chang-Soo;Choi, Pyung;Sohn, Byung-Ki
    • Journal of Sensor Science and Technology
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    • v.7 no.1
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    • pp.31-38
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    • 1998
  • Multi-channel sensors can be used to increase the reliability and remove the random iloise in ion-sensitive field effect transistors(ISFETs). Multi-channel sensors is also an essential step toward potential fabrication of sensors for several ionic species in one device. However, when the multi-channel sensors are separately biased, the biasing problems become difficult, that is to say, the bias circuit is needed as many sensors. In this work, a circuit for biasing the four pH-ISFETs in null-balance method, where bias voltages are switched, was proposed. The proposed concept is need only one bias circuit for the four sensors. Therefore it has advantages of smaller size and lower power consumption than the case that all sensors are separately biased at a time. The proposed circuit was tested with discrete devices and its performance was investigated. In the recent trend, sensor systems are implemented as portable systems. So the verified measurement circuit was integrated by using the CMOS circuit. Fortunately, ISFET fabrication process can be compatible with CMOS process. Full circuit has a mask area of $660{\mu}m{\times}500{\mu}m$. In the future, this step will be used for developing the smart sensor system with ISFET.

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