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time stamp technique using a nuclear emulsion multi-stage shifter for gamma-ray telescope

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2010年第2-3期620卷 192-195页

作者： Takahashi, Satoru Aoki, Shigeki Rokujo, Hiroki Hamada, Kaname Komatsu, Masahiro Morishima, Kunihiro Nakamura, Mitsuhiro Nakano, Toshiyuki Niwa, Kimio Sato, Osamu Yoshioka, Teppei Kodama, Koichi Nagoya Univ Nagoya Aichi 4648602 Japan Kobe Univ Nada Ku Kobe Hyogo 6578501 Japan Aichi Univ Educ Kariya Aichi 4488542 Japan

Nuclear emulsion has a potential use as a gamma-ray telescope with high angular resolution. For this application it is necessary to know the time when each track was recorded in the emulsion. In previous experiments using nuclear emulsion, various efforts were used to associate time to nuclear emulsion tracks and to improve the time resolution. Using a high speed readout system for nuclear emulsion together with a clock-based multi-stage emulsion shifter, we invented a technique to give a time-stamp to emulsion tracks and greatly improve the time resolution. A test experiment with a 2-stage shifter was used to demonstrate the principle of multi-stage shifting, and we achieved a time resolution 1.5 s for 12.1 h (about 1 part in 29 000) with the time stamp reliability 97% and the time stamp efficiency 98%. This multi-stage shifter can achieve the time resolution required for a gamma-ray telescope and can also be applied to another cosmic ray observations and accelerator experiments using nuclear emulsion. (C) 2010 Elsevier B.V. All rights reserved.

关键词： Nuclear emulsion time stamp time resolution Gamma-ray telescope

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time stamp in conditioned place avoidance can be set to different circadian phases

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NEUROBIOLOGY OF LEARNING AND MEMORY 2008年第4期89卷 591-594页

作者： Cain, Sean W. McDonald, Robert J. Ralph, Martin R. Univ Toronto Dept Psychol Ctr Biol Timing & Cognit Toronto ON M5S 3G3 Canada Univ Lethbridge Dept Psychol & Neurosci Canadian Ctr Behav Neurosci Lethbridge AB T1K 3M4 Canada

We have reported that the expression of conditioned place avoidance (CPA) in the golden hamster is regulated in a circadian pattern such that the preference is exhibited strongly at the circadian time of prior training but not at other circadian times [Cain, S. W., Chou, T., & Ralph, M. R. (2004a). Circadian modulation of performance on an aversion-based place learning task in hamsters. Behavioural Brain Research, 150(1-2), 201-205]. In that study, animals that were trained at a specific circadian time to discriminate between a "safe" context and one paired with foot shock, showed strong avoidance of the paired context at 24 and 48 h following the last training session, and showed no avoidance at 32 and 40 h following training. In the present study, we hypothesized that this "time stamp" effect is settable to any circadian phase. This was tested by training animals at one of two times of day (ZT 13 or ZT4) and testing whether a time stamp would be observed, with avoidance occurring only when training and testing times match. Results confirmed our hypothesis, suggesting that the time stamp in the performance of learned tasks can be set to any circadian phase. Such an ability may allow animals in nature to predict the recurrence of 24 h events, regardless of the time of day the event was encountered. (C) 2007 Elsevier Inc. All rights reserved.

关键词： CPA time of day learning learning and memory conditioning context place preference circadian rhythms time stamp

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An access control scheme based on Chinese remainder theorem and time stamp concept

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COMPUTERS & SECURITY 1996年第1期15卷 73-81页

作者： Hwang, MS Tzeng, WG Yang, WP MINIST TRANSPORTAT & COMMUN TELECOMMUN LABS CHUNGLI 320 TAIWAN

In this paper we propose a new dynamic access control method for the computer system with frequently inserted, deleted and updated users/files. Our method, based on the concepts of the access control matrix, key-lock-pair, time stamp and Chinese remainder theorem, associates each user with a user key and a user lock and each tile with a file key and a file lock Our method can achieve the following four goals. (1) By a simple module operation on the keys and locks of the user and the file, we can reveal the access right of a user to a file. (2) When a user/file is added to the computer system, we only assign a key and a lock to the user/file without affecting the keys and locks of the other users/files in the system. (3) When a user/file is deleted from the computer system, we simply erase the entry of the user/file in the computer system. (4) When the access right of a user to a file is updated, we merely modify the key and lock of the user or the file without affecting the keys and locks of the other users/files in the system. The main contribution of our method is that the action of inserting, deleting a user/file, or updating the access right of a user to a file can be done by modifying only one key and one lock, which could not be achieved simultaneously before.

关键词： access control matrix Chinese remainder theorem dynamic key-lock-pair time stamp

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Design of RFID Mutual Authentication Protocol using time stamp

Design of RFID Mutual Authentication Protocol using Time Sta...

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4th International Conference on Computer Sciences and Convergence Information Technology

作者： Cho, Chang-Hyun Do, Kyoung-Hwa Kim, Jae-Woo Jun, Moon-Seog SoongSil Univ Dept Comp Sci Seoul South Korea

ISBN: (纸本)9781424452446

Nowadays, there are many active studies and applications of RFID authentication protocol. Because RFID communicates wirelessly without contacting a reader, its communicated information is more likely to be exposed compared to ordinary wired communication area. Communicated information can be easily eavesdropped by external attacks and such stolen information can be used for malicious purpose, which causes security accidents. In order to complement such weakness, countless RFID authentication protocols have been studied. However, they still have weaknesses in tracking, replay attack and spoofing. In this paper, a protocol has been designed which is safe from tracking, replay attack and spoofing using time stamp which is generated also in Back-End DB unlike other existing protocols.

关键词： component RFID Authentication Mutual Authentication time stamp

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Dorson time stamp Brochure (January 11, 1965)

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2017年

Dorson time stamp Brochure (January 11, 1965): by published by

关键词： (january brochure company dorson dorson time feb high school illinois oct pression sep stamp time time stamp

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Researching Indistinguishability of the Polymorphism time stamp Watermarking

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INTERNATIONAL JOURNAL OF SECURITY AND ITS APPLICATIONS 2015年第7期9卷 299-305页

作者： Yin, Yifeng Wen, Heyu Fan, Kunpeng Zhengzhou Univ Light Ind Sch Comp & Commun Engn Zhengzhou 450002 Peoples R China

With the rapid development of computer network, digital watermarking, which is an effective digital products copyright protection technology, was widely applied in the security forensic. Those were analyzed that are the defects of existing time stamp scheme of digital watermarking and the characteristics of the pseudo-random sequence. The new scheme based on time stamp and pseudo-random sequence was proposed. Indistinguishability and scalability of watermark were analyzed from the experimental results. And other two aspects were obviously improved in the new scheme, which were in improving protocol's security and reducing the quantity of data embedded in digital works.

关键词： Digital watermarking time stamp Pseudo-random sequence

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Real-time range imaging by phase-stamp method using correlation image sensor

Real-time range imaging by phase-stamp method using correlat...

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9th Videometrics Conference

作者： Kimachi, Akira Ando, Shigeru Osaka Electrocommun Univ Neyagawa Osaka 5728530 Japan Univ Tokyo Bunkyo Ku Tokyo 1138656 Japan

ISBN: (纸本)9780819466044

This paper proposes a real-time phase-stamp range finder (PSRF) using a three-phase correlation image sensor (3PCIS). The system consists of the same components as in the conventional light-stripe range finder except the 3PCIS and a three-phase reference signal generator. During a single scan of the sheet beam, the 3PCIS "stamps" the phase of the reference signals at the moment the light stripe is imaged on each pixel. The three-dimensional shape of the object is obtained in real time by converting the detected phase to the angle of the projected sheet beam. Compared to time-stamp VLSI range finders, the proposed PSRF is not affected by spatial nonuniformity in surface reflectance of the object and background illumination. It can be realized with a simpler architecture than the modulation-type PSRF previously proposed by the authors. Experimental results on a developed PSRF system are demonstrated.

关键词： correlation image sensor range finder light stripe phase stamp time stamp three-phase demodulation

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On-Device Deep Learning for Retrieving System and User timestamps from Noisy Chat Images

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Procedia Computer Science 2025年 258卷 3760-3770页

作者： Kayarvizhy N Antara Roy Choudhury Rekha G S Bhuvan G Chandramouli Sanchi

Extracting information from scanned or digital images are helpful in different real time applications. Optical Character Recognition (OCR) is popular in extraction of information from digital images taken in the ideal lighting condition. But OCR method is not efficient when the images are scanned and clicked with the noisy and blurry environment. Deep learning-based OCR method performs good in text detection and localization in the digital images. Existing methods do not focus on the timestamp detection in screenshots. In this paper, YoloV5 (You Only Look Once) model and Faster RCNN (Faster Region-Convolutional Neural Network) are implemented to locate the region of time stamps from the screenshot images from various messaging applications. Our models take mobile screenshot of conversation applications as input and detect the system timestamps and User timestamps. 5k screenshot images have been collected from 16 messaging applications with various backgrounds. The images are annotated with 3 classes. YoloV5 and faster RCNN models are trained with the annotated dataset. Accuracy of YoloV5 model increased to 97.6 with training it with more dataset than RCNN and also the size is limited to 3.85MB.

关键词： time stamp Chat images RCNN YoloV5 Nano model

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Data Fusion of time stamps and Transmitted Data for Unsynchronized Beacons

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IEEE SENSORS JOURNAL 2015年第10期15卷 5946-5953页

作者： Traub-Ens, Alexander Bordoy, Joan Wendeberg, Johannes Reindl, Leonhard M. Schindelhauer, Christian Univ Freiburg D-79110 Freiburg Germany

Unsynchronized localization systems based on the measurement of time (difference) of arrival require reliable time stamps of the received signal. Noise, frequency shifts, and echoes disturb the signal and induce measurement errors of the time stamp, which leads to localization errors. Furthermore, the line of sight (LOS) signal has to be distinguished from the echoes to avoid false signal tracking. The proposed method combines the information of an ultrasound transmission with the measured time stamp and estimates the identifier. In our approach, the ultrasound transmission system uses phase-shift keying to modulate the signal. The received symbols and the time stamps are tracked and fused by the Kalman filter to increase the signal-to-noise ratio of the fused symbols and improve the validity of the decoding. Hence, the bias of the received symbols is tracked and the tracking allows to distinguish between the LOS signal and the echoes. As a result, the data fusion reduces the packet error rate from 70% at a distance of 21 m to 4.5%. Moreover, the median error of the localization is reduced from 7 to 4.6 cm.

关键词： Ultrasound localization communication data fusion beacon time stamp TDOA unsynchronized

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The use of time stamps in handling latency and concept drift in online learning

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EVOLVING SYSTEMS 2012年第4期3卷 203-220页

作者： Marrs, G. R. Black, M. M. Hickey, R. J. Univ Ulster Coleraine Londonderry North Ireland

Online classification learners operating under concept drift can be subject to latency in example arrival at the training base. The impact of such latency on the definition of a time stamp is discussed against the background of the online learning life cycle. Data stream latency is modeled in an example life-cycle integrated simulation environment. Two new algorithms are presented: CDTC versions 1 and 2, in which a specific time stamp protocol is used representing the time of classification. Comparison of these algorithms against previous time stamp learning algorithms CD3 and CD5 is made. A time stamp definition and algorithmic solution is presented for handling latency in data streams and improving classification recovery in such affected domains.

关键词： Online learning Classification Concept drift Latency time stamp

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