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991.
Chu-Yin Chang Anthony A. Maciejewski Venkataramanan Balakrishnan Rodney G. Roberts Kishor Saitwal 《Pattern Analysis & Applications》2007,10(1):15-31
Eigendecomposition-based techniques are popular for a number of computer vision problems, e.g., object and pose estimation,
because they are purely appearance based and they require few on-line computations. Unfortunately, they also typically require
an unobstructed view of the object whose pose is being detected. The presence of occlusion and background clutter precludes
the use of the normalizations that are typically applied and significantly alters the appearance of the object under detection.
This work presents an algorithm that is based on applying eigendecomposition to a quadtree representation of the image dataset
used to describe the appearance of an object. This allows decisions concerning the pose of an object to be based on only those
portions of the image in which the algorithm has determined that the object is not occluded. The accuracy and computational
efficiency of the proposed approach is evaluated on 16 different objects with up to 50% of the object being occluded and on
images of ships in a dockyard.
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献
Anthony A. MaciejewskiEmail: |
Chu-Yin Chang received the B.S. degree in mechanical engineering from National Central University, Chung-Li, Taiwan, ROC, in 1988, the M.S. degree in electrical engineering from the University of California, Davis, in 1993, and the Ph.D. degree in electrical and computer engineering from Purdue University, West Lafayette, in 1999. From 1999--2002, he was a Machine Vision Systems Engineer with Semiconductor Technologies and Instruments, Inc., Plano, TX. He is currently the Vice President of Energid Technologies, Cambridge, MA, USA. His research interests include computer vision, computer graphics, and robotics. Anthony A. Maciejewski received the BSEE, M.S., and Ph.D. degrees from Ohio State University in 1982, 1984, and 1987. From 1988 to 2001, he was a professor of Electrical and Computer Engineering at Purdue University, West Lafayette. He is currently the Department Head of Electrical and Computer Engineering at Colorado State University. He is a Fellow of the IEEE. A complete vita is available at: Venkataramanan Balakrishnan is Professor and Associate Head of Electrical and Computer Engineering at Purdue University, West Lafayette, Indiana. He received the B.Tech degree in electronics and communication and the President of India Gold Medal from the Indian Institute of Technology, Madras, in 1985. He then attended Stanford University, where he received the M.S. degree in statistics and the Ph.D. degree in electrical engineering in 1992. He joined Purdue University in 1994 after post-doctoral research at Stanford, CalTech and the University of Maryland. His primary research interests are in convex optimization and large-scale numerical algebra, applied to engineering problems. Rodney G. Roberts received B.S. degrees in Electrical Engineering and Mathematics from Rose-Hulman Institute of Technology in 1987 and an MSEE and Ph.D. in Electrical Engineering from Purdue University in 1988 and 1992, respectively. From 1992 until 1994, he was a National Research Council Fellow at Wright Patterson Air Force Base in Dayton, Ohio. Since 1994 he has been at the Florida A&M University---Florida State University College of Engineering where he is currently a Professor of Electrical and Computer Engineering. His research interests are in the areas of robotics and image processing. Kishor Saitwal received the Bachelor of Engineering (B.E.) degree in Instrumentation and Controls from Vishwakarma Institute of Technology, Pune, India, in 1998. He was ranked Third in the Pune University and was recipient of National Talent Search scholarship. He received the M.S. and Ph.D. degrees from the Electrical and Computer Engineering department, Colorado State University, Fort Collins, in 2001 and 2006, respectively. He is currently with Behavioral Recognition Systems, Inc. performing research in computer aided video surveillance systems. His research interests include image/video processing, computer vision, and robotics. 相似文献
992.
Monroe Scott M.; Roberts John E.; Kupfer David J.; Frank Ellen 《Canadian Metallurgical Quarterly》1996,105(3):313
Life stress was studied in relation to postrecovery attrition, symptom course, and recurrence of depression over 3 yrs. Participants were 67 individuals with recurrent depression who had responded to treatment. Life stress was assessed for the prior 12 wks at acute treatment entry (T1), initial recovery (T2), and after 17 wks of sustained recovery (T3). Severe life events at T1 predicted greater attrition, a more favorable postrecovery symptom course, and a lower likelihood of recurrence over 3 yrs. Life stress at T2 was not predictive of outcomes. Finally, undesirable life events at T3 tended to predict a worse symptom course and a higher likelihood of recurrence, particularly for individuals on medication. The findings are discussed in terms of (a) different processes influenced by life stress over time and (b) limitations of existing longitudinal research for studying the effects of life stress over prolonged intervals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
We propose a new position regulation strategy for VTOL-UAVs using IMU and GPS measurements. Since there is no sensor that measures the attitude, our approach does not rely on the knowledge (or reconstruction) of the system orientation as usually done in the existing literature. Instead, IMU and GPS measurements are directly incorporated in the control law. An important feature of the proposed strategy, is that the accelerometer is used to measure the apparent acceleration of the vehicle, as opposed to only measuring the gravity vector, which would otherwise lead to unexpected performance when the vehicle is accelerating (i.e. not in a hover configuration). 相似文献
994.
995.
Stanton Neville A. Plant Katherine L. Roberts Aaron P. Allison Craig K. Howell Mike 《Cognition, Technology & Work》2020,22(3):549-563
Cognition, Technology & Work - Degraded visual conditions present a great challenge to rotary-wing aircraft. These conditions can obscure cues used to interpret speed, location and approach.... 相似文献
996.
997.
DP Poppas JM Massicotte RB Stewart AB Roberts A Atala AB Retik MR Freeman 《Canadian Metallurgical Quarterly》1996,19(3):360-368
BACKGROUND AND OBJECTIVE: We examined the possibility that human albumin solder can be used as a vehicle for site specific delivery of growth factors for the purpose of accelerating tissue repair following laser welded wound closure. Certain human recombinant growth factors have been shown to accelerate wound healing in model systems. Pilot in vitro studies have established that several growth factors, including TGF-beta 1, maintain bioactivity following exposure to temperatures achieved during laser tissue welding. Using a temperature controlled laser delivery system (TCL) to precisely maintain welding temperatures, it is now possible to avoid thermal denaturation of exogenous bioactive molecules such as growth factors. STUDY DESIGN/MATERIALS AND METHODS: HB-EGF, bFGF, and TGF-beta 1 were tested in vitro for maintenance of bioactivity after exposure to 80 degrees C. In vivo experiments using porcine skin determined the efficacy of solders augmented with growth factors. Incisions were repaired using human albumin alone or supplemented with HB-EGF (2 micrograms), bFGF (10 micrograms), or TGF-beta 1 (1 microgram). Wounds were excised at 3, 5, and 7 days post-operatively. Tensile strength, total collagen content, and histology were performed. RESULTS: At 3 days, tensile strength (TS) of TGF-beta 1 wounds were 36% (P < 0.05) and 20% (n.s.) stronger than laser alone and suture closures, respectively. By 5 days the TS of the TGF-beta 1 group increased by 50% (P < 0.05) and 59% (P < 0.02) over laser alone and suture groups, respectively. At 7 days the TGF-beta 1 group was 50% (P < 0.05) and 79% (P < 0.01) stronger than laser solder alone or suture, respectively. The HB-EGF and bFGF groups were equivalent to the laser solder group at all time points. Total collagen TGF-beta 1 Accelerates Healing Following Laser Welding content at 7 days increased in the TGF-beta 1 group by 7% (n.s.) over the suture group and 21% (P < 0.05) in the laser group. CONCLUSION: Human albumin solder supplemented with TGF-beta 1 increases the early post-operative strength of laser welded wounds. This novel application of laser tissue soldering augmented with a growth factor has the potential to bring about immediate fluid tight seals while providing site specific delivery of biological modifiers. This may lead to an overall improvement in post-operative convalescence, wound infections, and hospital costs. 相似文献
998.
RW Lee LM Taylor GJ Landry SH Goodnight GL Moneta JM Edwards RA Yeager JM Porter 《Canadian Metallurgical Quarterly》1996,24(4):524-31; discussion 531-3
PURPOSE: The antiphospholipid antibodies (APL)-anticardiolipin antibodies (ACL) and lupus anticoagulant (LA)-are widely believed to be associated with decreased lower extremity bypass graft patency rates. To date, no prospective cohort study has confirmed this assumption. A prospective comparison of the result of infrainguinal revascularization procedures performed since 1990 in patients with and without APL forms the basis of this report. METHODS: Patients who underwent elective infrainguinal bypass procedures from 1990 to 1994 were evaluated for hypercoagulable states (ACL, LA, protein C, protein S, and antithrombin III). Patient data were prospectively entered in a computerized vascular registry, and postoperative follow-up was maintained for life. Graft patency, limb salvage, and patient survival rates were calculated by life-table methods. RESULTS: Three hundred twenty-seven lower extremity bypass grafting procedures were performed in 262 patients. APLs were present in 83 patients (32%); 70 patients (84%) had ACLs only, 11 patients (13%) had LA only, and two patients (3%) had both ACLs and LA. There was no significant difference between APL-positive and APL-negative patients with respect to demographics, associated medical conditions, indication for operations, and type of procedures performed. More patients who had APLs had warfarin treatment after surgery (43% vs 24%, p = 0.002). Life table 4-year primary patency rates showed minimal difference (APL-positive, 43%; APL-negative, 59%; p = 0.087), and no significant difference was noted in assisted primary patency rates (APL positive, 72%; APL negative, 73%; p = NS), limb salvage rates (APL positive, 79%; APL negative, 88%; p = NS), and patient survival rates (APL positive, 67%; APL negative, 66%; p = NS). CONCLUSIONS: APLs were found in a surprising one third of the patients who underwent leg bypass grafting procedures. The majority of APLs identified were ACLs (87%). There was minimal difference in graft primary patency rates, and no difference in assisted primary patency, limb salvage, and survival rates between patients with and without APLs who underwent leg bypass grafting procedures. The extreme morbidity rate associated with APLs in previous reports is not confirmed by this prospective study. APLs should not be regarded as a contraindication to indicated leg bypass grafting procedures. 相似文献
999.
SH Yoo 《Canadian Metallurgical Quarterly》1996,271(3):1558-1565
Chromogranins A and B (CGA and CGB), the major proteins of the secretory vesicles of the regulated secretory pathway, have been shown to aggregate in a low pH and high calcium environment, the condition found in the trans-Golgi network where secretory vesicles are formed. Moreover, CGA and CGB, as well as several other secretory vesicle matrix proteins, have recently been shown to bind to the vesicle membrane at the intravesicular pH of 5.5 and to be released from it at a near physiological pH of 7.5. The pH- and Ca(2+)-dependent aggregation and interaction of chromogranins, as well as several other matrix proteins, with the vesicle membrane are considered essential in vesicle biogenesis. Therefore, to gain further insight into how vesicle matrix proteins find their way into the secretory vesicles, the pH- and Ca(2+)-dependent aggregation and vesicle membrane binding properties of the vesicle matrix proteins were studied, and it was found that most of the vesicle matrix proteins aggregated in the presence of Ca2+ at the intravesicular pH of 5.5. Furthermore, most of the vesicle matrix proteins bound not only to the vesicle membrane but also to CGA at pH 5.5, with the exception of a few matrix proteins that appeared to bind only to CGA or to vesicle membrane. Purified CGB was also shown to interact with CGA at pH 5.5. The extent and Ca(2+)-sensitivity of the aggregation of vesicle matrix proteins lay between those of purified CGB and CGA, CGB aggregation showing the highest degree of aggregation and being the most Ca2+ sensitive at a given protein concentration. Hence, in view of the abundance of chromogranins in secretory vesicles and their low pH- and high calcium-dependent aggregation property, combined with their ability to interact with both the vesicle matrix proteins and the vesicle membrane, CGA and CGB are proposed to play essential roles in the selective aggregation and sorting of potential vesicle matrix proteins to the immature secretory vesicles of the regulated secretory pathway. 相似文献
1000.