A5062673867- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- High-pressure geophysics and materials
- Astrophysical Phenomena and Observations
- Seismic Waves and Analysis
- Geophysics and Sensor Technology
- Astrophysics and Cosmic Phenomena
- Advanced X-ray and CT Imaging
- Medical Imaging Techniques and Applications
- Digital Radiography and Breast Imaging
- Security and Verification in Computing
- Software System Performance and Reliability
- Network Packet Processing and Optimization
- Seismic Imaging and Inversion Techniques
- Context-Aware Activity Recognition Systems
- Statistical and numerical algorithms
- Radio Astronomy Observations and Technology
- Radiology practices and education
- Cloud Data Security Solutions
- Advanced Malware Detection Techniques
- Technology and Data Analysis
- Vehicular Ad Hoc Networks (VANETs)
- Dark Matter and Cosmic Phenomena
Ulsan National Institute of Science and Technology
2020-2024
National Astronomical Observatory of Japan
2023
RELX Group (Netherlands)
2023
Pusan National University
2017-2020
KAGRA is a newly built gravitational wave observatory, laser interferometer with 3 km arm length, located in Kamioka, Gifu, Japan. In this series of articles, we present an overview the baseline KAGRA, for which finished installing designed configuration 2019. This article describes method calibration (CAL) used reconstructing signals from detector outputs, as well characterization (DET). We also review physical environmental monitors (PEM) system and geophysics (GIF). Both are...
Abstract KAGRA is a newly build gravitational wave observatory, laser interferometer with 3 km arm length, located in Kamioka, Gifu, Japan. In this paper, one of series articles featuring KAGRA, we discuss the science targets projects, considering not only baseline (current design) but also its future upgrade candidates (KAGRA+) for near to middle term ($\sim$5 years).
Abstract KAGRA, the kilometer-scale underground gravitational-wave detector, is located at Kamioka, Japan. In April 2020, an astrophysics observation was performed KAGRA detector in combination with GEO 600 detector; this operation called O3GK. The optical configuration O3GK based on a power-recycled Fabry–Pérot–Michelson interferometer; all mirrors were set room temperature. duty factor of approximately 53%, and displacement sensitivity 1 × 10−18 ${\rm m}/\sqrt{\rm {Hz}}$ 250 Hz....
Abstract KAGRA is an underground interferometric gravitational wave detector which currently being commissioned. This relies on high-performance vibration-isolation systems to suspend its key optical components. These suspensions come in four different configurations, of the type-B used for beam splitter and signal recycling mirrors. The suspension comprises payload, three geometric anti-spring filters vertical isolation one inverted pendulum horizontal isolation. payload optic, marionette...
In April 2020, KAGRA conducted its first science observation in combination with the GEO~600 detector (O3GK) for two weeks. According to noise budget estimation, suspension control low frequency band and acoustic middle are identified as dominant contribution. this study, we show that such can be reduced offline data analysis by utilizing a method called Independent Component Analysis (ICA). Here ICA model is extended from one studied iKAGRA incorporating dependence while linearity...
The sandwich-like multilayer detector can have a unique characteristic when it employs two layers having different spatial-resolution properties to each other. Reconstruction of dual-energy (DE) images using weighted log-subtraction technique then results in the unsharp masking-like effect on resultant images. We developed simple model describing signal and noise sandwich detector-based DE computed tomography (CT) linear-systems theory. Applying laboratory micro-CT system, we measured...
The Save a Life (SAL) Maps addresses the challenge of traffic congestion affecting emergency services and provides swift response during life-critical situations. A path clearance algorithm is integrated into an application, which identifies most optimal routes enabling to navigate efficiently. incorporates mechanism that uses micro facilitate for services, provide fastest routes, assist general public in accessing notify police high by manually clearing out path. Docker employed...
An operating system kernel has the highest privilege in most computer systems, making its code integrity critical to entire system's security. Failure protect allows an attacker modify pages directly or trick into executing instructions stored outside pages. Existing prevention mechanisms rely on memory management unit which certain are marked as not-executable supervisor mode prevent such attacks. However, can bypass these existing by manipulating page table contents mark with malicious...
Abstract KAGRA is a newly built gravitational wave observatory, laser interferometer with 3 km arm length, located in Kamioka, Gifu prefecture, Japan. In this article, we describe the data management system, i.e., recording of data, transfer from experiment site to computing resources, as well distribution tier sites, including international sites Taiwan and Korea. The amount exceeded 1.0 PiB increased by about 1.5 TB per day during operation 2020. Our system has succeeded management,...
For digital x-ray tomosynthesis of thin slab objects, we compare the tomographic imaging performances obtained from filtered backprojection (FBP) and simultaneous algebraic reconstruction (SART) algorithms. The performance includes in-plane molulation-transfer function (MTF), signal difference-to-noise ratio (SDNR), out-of-plane blur artifact or artifact-spread (ASF). MTF is measured using a tungsten-wire phantom, SDNR ASF are aluminum-disc phantom embedded in plastic cylinder. FBP shows...
Dual-energy imaging techniques based on the fast kVp switching and sandwich detector can enhance conspicuity in digital radiography. Deep learning is an alternative promising approach to obtain dual-energy images without hardware cost additional patient dose. This paper extends well-known multi-scale U-net preserve high-frequency information so as be applicable structural filtering of medical with minimal loss information. The performance modified versions presented comparison conventional...
응용 특화 프로세서들은 목표 도메인에서의 성능 극대화를 위해 자주 쓰이는 연산들을 위한 명령어들을 가진다. 프로세서를 프로그램은 명령어를 사용하기 때문에 이들의 의미명세가 있어야 기호 실행기 등 고급 소프트웨어 분석 도구를 적용하는 것이 가능해진다. 이에 이 연구에서는 프로세서 구현 과정에서 반드시 작성해야 하는 레지스터 전송 레벨(RTL) 수준 구현으로 부터 명령어의 의미(semantics)을 자동으로 추출하는 시스템인 SemTracter를 개발하였다. SemTracter는 프로세서의 RTL을 실행해서 각 의미명세를 얻고 이를 ISA 명세 작성을 개발된 언어인 Sail로 표현한다. 간단한 구현된 5-stage RISC-V 프로세서로부터 몇 가지 성공적으로 추출하였으며, 이는 직접 사람이 작성한 명세와 비교하여 일치하는 것을 확인하였다.
In relation with a thin slab-object inspection, we propose digital tomosynthesis reconstruction fewer numbers of measured projections in combinations additional virtual projections, which are produced by interpolating the projections. Hence can reconstruct tomographic images less few-view artifacts. The projection interpolation assumes that variations cone-beam ray path-lengths through an object negligible and is rigid. performed projection-space domain. Pixel values interpolated weighted...
Abstract KAGRA, the underground and cryogenic gravitational-wave detector, was operated for its solo observation from February 25 to March 10, 2020, first joint with GEO 600 detector April 7 21, 2020 (O3GK). This study presents an overview of input optics systems KAGRA which consist various optical systems, such as a laser source, intensity frequency stabilization modulators, Faraday isolator, mode-matching telescopes, high-power beam dump. These were successfully delivered interferometer...