15224900
A Novel Clock Duty-Cycle Corrector of DSP Systems
A novel 50% duty-cycle corrector (DCC) of digital signal processing (DSP) systems, designed with a purely digital phase-blending technique, is presented in this paper. The novel features of the proposed DCC includes a higher reliability against process, voltage and temperature variation due to the use of the synchronous mirror delay (SMD) technique, no-skew output clock, and a much faster duty-cycle correction speed compared to conventional DCC's. When designed with a 0.13-μm CMOS technology, the acceptable duty-cycle of the input signal ranges from 10% to 90% when the clock frequency is 400 MHz and the correction operation spends 4 clock cycles with the corrected duty-cycle varying from 48% to 52%.
18783200
A Novel Low-Power Clock Skew Compensation Circuit
The clock is a periodic synchronization signal used as a time reference for data transfers in synchronous digital systems. However, the clock skew constrains the improvement of clock frequencies and affects the reliability of systems. One skew reduction technique is the use of clock deskew circuits. They can be classified into two methods: delay-locked loop (DLL) deskewing and synchronous mirror delay (SMD) deskewing. The DLL deskewing achieves a fine accuracy, but suffers from slow locking. Reversely, the adjustment of the SMD deskewing is fast, but suffers from a poor accuracy. In this paper, a low-power full-digital hybrid clock deskew circuit is presented. It uses a SMD as coarse delay line and a digital-DLL as a fine delay line. The SPICE simulation shows that the proposed clock deskew circuit achieves fine accuracy , fast locking, and low power.
2819430
Comments on "Leading-One Prediction with Concurrent Position Correction"
In this report, we first point out and analyse an error in the implementation of the pre-encoding logic in the LOP module proposed in [1], and then present a modification method.
13494891
Tracking Telescope Aiming Point for Bioptic Driving Surveillance
Bioptic telescope is a visual aid used by some people with impaired vision for driving and to qualify for licensing. Data on how and when bioptic drivers use the telescope and what they look at with it are important in biop- tic driving studies. A video-based technique to track bioptic drivers' spectacle frames, which represent telescope aiming point, is presented in this paper. With three retro-reflective markers pasted on the bioptic spectacles frame, aiming point is determined from the angles formed by the three markers. Telescope aiming points projected on a scene camera image is calculated by means of interpolation based on a novel calibration method in which a laser pointer is mounted on the spectacle frame. A large number of calibration points are sampled automatically when the driver scans across the scene. Preliminary experiment demonstrated that the average error over a 65° ×48° field was only 0.89 degree.
6462785
Intelligent Output Interface for Intelligent Medical Search Engine
To facilitate ordinary people to search medical information, we have built an intelligent medical Web search engine called iMed. iMed uses medical knowledge and an interactive questionnaire to find multiple diseases serving as queries. The search results of these queries are combined together and returned to the searcher in a traditional sequential order. Nevertheless, searchers still frequently miss desired information, because the traditional search result output interface cannot capture the internal structures of medical search results. This paper presents a new, intelligent search result output interface devoted to intelligent medical search. The new output interface automatically offers searchers what they want instead of waiting until they ask explicitly. It structures all the search results into a multi-level hierarchy with explicitly marked medical meanings. In this way, searchers can efficiently navigate among all the search results and quickly obtain desired information. We demonstrate the effectiveness of our techniques through an evaluation using USMLE medical exam cases.
5329853
Generating Tests for Control Portion of SDL Specifications
ABSTRACT The signal SAVE construct is one of the features distinguishing SDL from convent specification and programming languages. On the other hand, this feature increase testing SDL-specified software. We present a testing approach consisting of the foll SDL specifications are first abstracted into finite state machines with save constructs machines are transformed to equivalent finite state machines without save construc are selected from the resulting finite state machines. In particular, we give a fault m selection. We come up with an equivalent transformation method which works for constructs for which equivalent FSMs exist. We also investigate the detection of fa queue.
2438435
Real-time new event detection for video streams
Online detection of video clips that present previously unseen events in a video stream is still an open challenge to date. For this online new event detection (ONED) task, existing studies mainly focus on optimizing the detection accuracy instead of the detection efficiency. As a result, it is difficult for existing systems to detect new events in real time, especially for large-scale video collections such as the video content available on the Web. In this paper, we propose several scalable techniques to improve the video processing speed of a baseline ONED system by orders of magnitude without sacrificing much detection accuracy. First, we use text features alone to filter out most of the non-new-event clips and to skip those expensive but unnecessary steps including image feature extraction and image similarity computation. Second, we use a combination of indexing and compression methods to speed up text processing. We implemented a prototype of our optimized ONED system on top of IBM's System S. The effectiveness of our techniques is evaluated on the standard TRECVID 2005 benchmark, which demonstrates that our techniques can achieve a 480-fold speedup with detection accuracy degraded less than 5%.
11663917
On iterative intelligent medical search
Searching for medical information on the Web has become highly popular, but it remains a challenging task because searchers are often uncertain about their exact medical situations and unfamiliar with medical terminology. To address this challenge, we have built an intelligent medical Web search engine called iMed, which uses medical knowledge and an interactive questionnaire to help searchers form queries. This paper focuses on iMed's iterative search advisor, which integrates medical and linguistic knowledge to help searchers improve search results iteratively. Such an iterative process is common for general Web search, and especially crucial for medical Web search, because searchers often miss desired search results due to their limited medical knowledge and the task's inherent difficulty. iMed's iterative search advisor helps the searcher in several ways. First, relevant symptoms and signs are automatically suggested based on the searcher's description of his situation. Second, instead of taking for granted the searcher's answers to the questions, iMed ranks and recommends alternative answers according to their likelihoods of being the correct answers. Third, related MeSH medical phrases are suggested to help the searcher refine his situation description. We demonstrate the effectiveness of iMed's iterative search advisor by evaluating it using real medical case records and USMLE medical exam questions.