• Title/Summary/Keyword: PSD

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Improved fast neutron detection using CNN-based pulse shape discrimination

  • Seonkwang Yoon;Chaehun Lee;Hee Seo;Ho-Dong Kim
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.3925-3934
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    • 2023
  • The importance of fast neutron detection for nuclear safeguards purposes has increased due to its potential advantages such as reasonable cost and higher precision for larger sample masses of nuclear materials. Pulse-shape discrimination (PSD) is inevitably used to discriminate neutron- and gamma-ray- induced signals from organic scintillators of very high gamma sensitivity. The light output (LO) threshold corresponding to several MeV of recoiled proton energy could be necessary to achieve fine PSD performance. However, this leads to neutron count losses and possible distortion of results obtained by neutron multiplicity counting (NMC)-based nuclear material accountancy (NMA). Moreover, conventional PSD techniques are not effective for counting of neutrons in a high-gamma-ray environment, even under a sufficiently high LO threshold. In the present work, PSD performance (figure-of-merit, FOM) according to LO bands was confirmed using a conventional charge comparison method (CCM) and compared with results obtained by convolution neural network (CNN)-based PSD algorithms. Also, it was attempted, for the first time ever, to reject fake neutron signals from distorted PSD regions where neutron-induced signals are normally detected. The overall results indicated that higher neutron detection efficiency with better accuracy could be achieved via CNN-based PSD algorithms.

Development of Onboard Power Supply Device for Precision Guided Kit (정밀유도 비행체 탑재용 전원공급장치 개발)

  • Park, Deok-Bae;Kim, Hyung-Shin
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.3
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    • pp.209-214
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    • 2008
  • A precision guided kit is a GPS/INS guided range extension system to improve the accuracy and availability of existing dumb bombs. The PSD(power supply device) installed in the GPS guided kit supplies electrical power to all electrical loads in the kit. In this paper, design process and test results of the PSD have been presented. Additionally, the performance results of the PSD during actual ground and flight tests have been described.

Relative Navigation Study Using Multiple PSD Sensor and Beacon Module Based on Kalman Filter (복수 PSD와 비콘을 이용한 칼만필터 기반 상대항법에 대한 연구)

  • Song, Jeonggyu;Jeong, Junho;Yang, Seungwon;Kim, Seungkeun;Suk, Jinyoung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.3
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    • pp.219-229
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    • 2018
  • This paper proposes Kalman Filter-based relative navigation algorithms for proximity tasks such as rendezvous/docking/cluster-operation of spacecraft using PSD Sensors and Infrared Beacon Modules. Numerical simulations are performed for comparative analysis of the performance of each relative-navigation technique. Based on the operation principle and optical modeling of the PSD Sensor and the Infrared Beacon Module used in the relative navigation algorithm, a measurement model for the Kalman filter is constructed. The Extended Kalman Filter(EKF) and the Unscented Kalman Filter(UKF) are used as probabilistic relative navigation based on measurement fusion to utilize kinematics and dynamics information on translational and rotation motions of satellites. Relative position and relative attitude estimation performance of two filters is compared. Especially, through the simulation of various scenarios, performance changes are also investigated depending on the number of PSD Sensors and IR Beacons in target and chaser satellites.

Pigment particle size distribution이 백판지 품질에 미치는 영향

  • 김진현;이도엽;최강영
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2001.11a
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    • pp.55-56
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    • 2001
  • 지난 수년간 유럽을 중심으로 Carbonate의 PSD (Particle Size Distribution)가 도공지 의 백색도, 불투명도, Coverage등에 미치는 영향에 대하여 많은 연구가 진행되어 왔다. 현재 국내의 Coating Pigment System 역시 Carbonate 위주로 구성되어 있으나, 입자 분포에 따른 실증적 연구가 선진국에 비하여 부족한 상태이다. 본 연구는 최근 유럽에서 사용 중인 Narrow PSD Carbonate가 도공지 품질에 미치는 영향을 검토한 것으로서, 특히 Multiple Coating에서의 도공층 구조변화와 그에 따른 백지물성 및 인쇄적성의 변화를 연구한 것이다. 실험의 Case는 Broad PSD CaC03와 Narrow PSD CaC03를 비 교하였 다 .. Color F Formulation은 Pre Color에서 #1 Clay 30 p따t와 각각 CaC03 70 p따t를 사용하였다. 그리고 바인더와 첨가제는 동일하게 사용하였다 .. Top color Formulation 또한 동일하 게 사용하였다. 코팅방식은 speed 450rrνmin, pre rod coating, top blade coating 방식 으로 CLC (Cy lindrical Laboratory Coater)를 사용하여 코팅하였다. 백지품질은 백색도, 평활도 ,광택도, 거칠음도, Bum Out Test와 Coverage( SEM 사 진 Z -direction) 등을 측정하였다. 인쇄품질은 인쇄 광택도, 인쇄 Picking strength와 2 도 인쇄 농도를 측정하였다. 백색도는 Narrow PSD CaC03를 사용한 것이 Broad PSD CaC03를 사용한 것 대비 약1% 우수하였다. 이것은 Narrow PSD CaC03를 사용한 것이 filter cake이 많이 open 되 어 있어 dewatering이 빠르고, Wet void volume이 증가되 어 부동화점 의 농도가 낮 아져 원지 층으로 침 투되 는 pigment가 작고 표층에 잔류하는 pigment와 void volume의 증가로 인해 기공층이 증가한 것으로 판단된다. 그리고, 백지광택도, 거칠음도 등 또한 Narrow PSD CaC03를 사용한 것이 우수하였 다. 이는 Pre color에서 coverage의 개선으로 top color층의 도공량 uniformity가 개선 된 이유라고 생각한다. 그러나 인쇄품질은 백지와 비교하여 차이가 없었다. 이것은 top 칼라 Formulation이 동일하고, 인쇄시 잉크흡수 거동은 top color 층에 주로 영향을 받기 때문이라고 판단 된다. 향후에는 인쇄품질의 향상을 위하여 Case 2의 CaC03 100% 사용가능성 및 Pre Color 는 Case 2로 고정하고, Top칼라를 변경하는 방법을 또한 생각할 필요가 있다고 판단된다.

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Study of Efficacy and Safety of Tianwangbuxin-dan for Poststroke Depression: A Randomized, Double Blinded, Non-inferiority Trial (뇌졸중 후 우울증에 대한 천왕보심단의 유효성 및 안전성 연구 : 무작위 배정, 이중맹검, 비열등성 연구)

  • Lee, Il-Suk;Kim, Mun-Soo;Lee, Sang-Kwan
    • The Journal of Internal Korean Medicine
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    • v.35 no.2
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    • pp.145-156
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    • 2014
  • Objectives : The aim of this study was to compare Tianwangbuxin-dan to Fluoxetine for antidepressive efficacy and safety in poststroke depression (PSD). Methods : A randomized, double blinded, non-inferiority trial was conducted. 113 PSD patients were recruited from a stroke center. Except for the 25 excluded patients, 88 PSD patients were randomly given either Tianwangbuxin-dan 1100 mg or Fluoxetine 20 mg per a day for 16 weeks. PSD was evaluated using Beck's depression inventory (BDI) and Hamilton depression rating scale (HDRS) and followed every fourth week. Repeated measure analysis of variance (ANOVA) was used to compare and contrast the depression scores of the two groups and to compare them among the evaluation times, at the beginning, $4^{th}$, $8^{th}$, $12^{th}$ and $16^{th}$ weeks. In addition, independent t-tests were used to find the difference between two groups at every evaluation time. Results : Finally, 88 PSD patients were included in the study, 63 PSD patients completed the procedure and 25 PSD patients were dropped out by the incompliance or withdrawal of consent. Tianwangbuxin-dan (or Fluoxetine) improved the depression of stroke patients and the efficacy of Tianwangbuxin-dan was not inferior to that of Fluoxetine. In addition, there was no significant side effect in two groups. Conclusions : This study showed that antidepressive efficacy and safety of Tianwangbuxin-dan in PSD patients.

Kinematic Envelope Analysis of the Urban Transit EMU based on PSD Installation (PSD 설치에 따른 도시철도차량의 동적 거동 분석)

  • Chung, Jong-Duk;Ohn, Jung-Ghun;Pyun, Jang-Sik;Park, Jang-Gon;Lee, Jong-Woo
    • Journal of the Korean Society for Railway
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    • v.16 no.6
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    • pp.447-453
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    • 2013
  • Since PSDs(Platform Screen Doors) are set up at many subway stations, their design related to safety has become gradually important. In particular, the interference check with a running railway vehicle is the most important of performance indices because the collision between PSDs and vehicles can be dangerous for passengers in the car and on platforms. When the train comes into a station with a curvature, the passenger car has a large translational and rotational motion and the displacement is enough for coming in contact with PSD. The performance is affected by many design parameters such as rail design parameters and vehicle velocity. This study proposes dynamic analysis models for railway vehicles and rails. Some parameters were also considered in the models to determine their influence on the performance.

A Study on Privacy Protection in Financial Mydata Policy through Comparison of the EU's PSD2 (유럽 PSD2 시행에 따른 금융분야 마이데이터 정책의 개인정보보호 강화 방안 연구)

  • Song, Mi-Jung;Kim, In-Seok
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.29 no.5
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    • pp.1205-1219
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    • 2019
  • As the ability to use data becomes competitive power in the data-driven economy, the effort to create economic value by using personal data is emphasized as much as to protect personal data. EU's PSD2(the second Payment Service directive) became the initiative of the Open Banking trends all over the world, as it is the Mydata policy which protects the data subject's right by empowering the subject to control over the personal data with the right to data portability and promotes personal data usages and transfer. Korean government is now fast adopting EU's PSD2 in financial sector, but there is growing concerns in personal data abuse and misuse, and data breach. This study analyzes domestic financial Mydata policy in comparison with EU's PSD2 and focus on Personal information life-cycle risks of financial Mydata policy. Some suggestions on how to promote personal information and privacy in domestic financial Mydata Policy will be given.