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71.
72.
Maureen T. Ross Rena Cruz Trent L. Brooks-Richards Louise M. Hafner Sean K. Powell Maria A. Woodruff 《Virtual and Physical Prototyping》2018,13(4):255-265
Congenital facial anomalies, such as microtia (malformation of the external ear), lead to significant psychosocial effects starting from early childhood. Three-dimensional (3D) scanning and advanced manufacturing are being investigated as a cheaper and more personalised method of fabricating reconstructive treatments for patients compared to traditional approaches. To date, most case studies have used expensive 3D scanners, yet, there is potential for low-cost devices to provide comparable results. This study aimed to investigate these different approaches. Both ears of 16 adult participants were scanned with three devices: Artec Spider (Artec Group), Intel® RealSense? (Intel), and the Apple iPhone® 7 (Apple Inc.) combined with photogrammetry using 90, 60 and 30 photographs. The scanning time, processing time, accuracy, completeness, resolution and repeatability of each technique were assessed using the Artec Spider as a reference scanner. Our results show that the iPhone had the longest processing time however, this decreased nine-fold when reducing the number of photos from 90 to 30. There was no significant difference in the accuracy, completeness or repeatability of the iPhone scans with 90 photographs (1.4?±?0.6?mm, 79.9%, 1.0?±?0.1?mm), 60 photographs (1.2?±?0.2, 79.3%, 0.9?±?0.2?mm) or 30 photographs (1.2?±?0.3?mm, 74.3%, 1.0?±?0.2?mm). The Intel RealSesne performed significantly worse in each parameter (1.8?±?03?mm; 46.6%, 1.4?±?0.5). Additionally, the RealSense had significantly lower resolution with not enough detail captured for the application. These results demonstrate that the ear can be accurately 3D scanned using iPhone photographs. We would recommend capturing between 30 and 60 photographs of the ear to create a scan that is accurate but without the downfall of long processing time. Using these methods we aim to provide a more comfortable setting for the patient and a lower-cost and more personalised ear prosthesis. 相似文献
73.
L Tonella BJ Walsh JC Sanchez K Ou MR Wilkins M Tyler S Frutiger AA Gooley I Pescaru RD Appel JX Yan A Bairoch C Hoogland FS Morch GJ Hughes KL Williams DF Hochstrasser 《Canadian Metallurgical Quarterly》1998,19(11):1960-1971
The combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), computer image analysis and several protein identification techniques allowed the Escherichia coli SWISS-2DPAGE database to be established. This is part of the ExPASy molecular biology server accessible through the WWW at the URL address http://www.expasy.ch/ch2d/ch2d-top.html . Here we report recent progress in the development of the E. coli SWISS-2DPAGE database. Proteins were separated with immobilized pH gradients in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. To increase the resolution of the separation and thus the number of identified proteins, a variety of wide and narrow range immobilized pH gradients were used in the first dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride membranes and spots were visualized by amido black staining. Protein identification techniques such as amino acid composition analysis, gel comparison and microsequencing were used, as well as a recently described Edman "sequence tag" approach. Some of the above identification techniques were coupled with database searching tools. Currently 231 polypeptides are identified on the E. coli SWISS-2DPAGE map: 64 have been identified by N-terminal microsequencing, 39 by amino acid composition, and 82 by sequence tag. Of 153 proteins putatively identified by gel comparison, 65 have been confirmed. Many proteins have been identified using more than one technique. Faster progress in the E. coli proteome project will now be possible with advances in biochemical methodology and with the completion of the entire E. coli genome. 相似文献
74.
It is widely recognised that impaired social relations are characteristic of school-aged children with behavioural disorders, and predict a poor long-term outcome (Parker & Asher, 1987). However, little is known about the early antecedents of social impairment in behaviourally disturbed children. The aim of the present study was to explore three areas of potential dysfunction in younger children: theory of mind, emotion understanding, and executive function. Forty preschoolers, rated by their parents on the Strengths and Difficulties Questionnaire (Goodman, 1994) as "hard to manage" (H2M) were compared with a control group on a set of: (1) theory of mind tasks (including an emotion prediction task involving either a nice or a nasty surprise); (2) emotion understanding stories (that required affective perspective-taking skills as well as situational understanding); and (3) simple executive function tasks (adapted for preschoolers, and tapping inhibitory control, attentional set-shifting, and working memory). Small but significant group differences were found in all three cognitive domains. In particular, hard-to-manage preschoolers showed poor understanding of emotion and executive control, poor prediction or recall of a false belief, and better understanding of the belief-dependency of emotion in the context of a trick than a treat. Moreover, executive function was associated with performance on the theory of mind tasks for the hard-to-manage group alone, suggesting both direct and indirect links between executive dysfunction and disruptive behaviour. 相似文献
75.
Koval D.O. Bocancea R.A. Kai Yao Hughes M.B. 《Industry Applications, IEEE Transactions on》1998,34(5):904-910
The occurrence of voltage sags and surges originating on the primary and secondary sides of industrial facilities can disrupt continuous and noncontinuous industrial computer processes, a costly issue for society. This paper attempts to answer several questions concerning the frequency and duration of voltage sags and surges posed by industrial customers. The answers to these questions are based on the national survey results of the frequency and duration of voltage sags and surges at industrial sites monitored at their utilization voltage levels (e.g. 120, 347 V) and on the utility primary side of their facilities. The survey results provide a knowledge base for monitoring, designing, and utilizing voltage sag and surge mitigating technologies 相似文献
76.
R Wrigglesworth CS Walpole S Bevan EA Campbell A Dray GA Hughes I James KJ Masdin J Winter 《Canadian Metallurgical Quarterly》1996,39(25):4942-4951
Structural features of three regions of the capsaicin molecule necessary for agonist properties were delineated by a previously reported modular approach. These in vitro agonist effects were shown to correlate with analgesic potency in rodent models. Combination of optimal structural features from each of these regions of the capsaicin molecule have led to highly potent agonists (eg., 1b). Evaluation in vivo established that 1b had analgesic properties but poor oral activity, short duration of action, and excitatory side effects which precluded further development of this compound. Preliminary metabolism studies had shown that the phenol moiety of 1b was rapidly glucuronidated in vivo, providing a possible explanation for the poor pharmacokinetic profile. Subsequent specific modification of the phenol group led to compounds 2a-j, which retained in vitro potency. The in vivo profiles of two representatives of this series, 2a,h, were much improved over the "parent" phenol series, and they are candidates for development as analgesic agents. 相似文献
77.
Jennifer J. Burg Sheau-Dong Lang Charles E. Hughes 《Annals of Mathematics and Artificial Intelligence》1996,17(2):189-211
CLP() is a constraint logic programming language in which constraints can be expressed in the domain of real numbers. Computation in this specialized domain gives access to information useful in intelligent backtracking. In this paper, we present an efficient constraint satisfaction algorithm for linear constraints in the real number domain and show that our algorithm directly generates minimal sets of conflicting constraints when failures occur. We demonstrate how information gleaned during constraint satisfaction can be integrated with unification failure analysis. The resulting intelligent backtracking method works in the context of a two-sorted domain, where variables can be bound to either structured terms or real number expressions. We discuss the implementation of backtracking and show examples where the benefit of pruning the search tree outweights the overhead of failure analysis. 相似文献
78.
Stephanie Kemna Michael J. Hamilton David T. Hughes Kevin D. LePage 《Intelligent Service Robotics》2011,4(4):245-258
Autonomous underwater vehicles (AUVs) have gained more interest in recent years for military as well as civilian applications.
One potential application of AUVs is for the purpose of undersea surveillance. As research into undersea surveillance using
AUVs progresses, issues arise as to how an AUV acquires, acts on, and shares information about the undersea battle space.
These issues naturally touch on aspects of vehicle autonomy and underwater communications, and need to be resolved through
a spiral development process that includes at sea experimentation. This paper presents a recent AUV implementation for active
anti-submarine warfare tested at sea in the summer of 2010. On-board signal processing capabilities and an adaptive behavior
are discussed in both a simulation and experimental context. The implications for underwater surveillance using AUVs are discussed. 相似文献
79.
Privacy in geo-social networks: proximity notification with untrusted service providers and curious buddies 总被引:2,自引:0,他引:2
Sergio Mascetti Dario Freni Claudio Bettini X. Sean Wang Sushil Jajodia 《The VLDB Journal The International Journal on Very Large Data Bases》2011,20(4):541-566
A major feature of the emerging geo-social networks is the ability to notify a user when any of his friends (also called buddies)
happens to be geographically in proximity. This proximity service is usually offered by the network itself or by a third party service provider (SP) using location data acquired from the
users. This paper provides a rigorous theoretical and experimental analysis of the existing solutions for the location privacy
problem in proximity services. This is a serious problem for users who do not trust the SP to handle their location data and
would only like to release their location information in a generalized form to participating buddies. The paper presents two
new protocols providing complete privacy with respect to the SP and controllable privacy with respect to the buddies. The
analytical and experimental analysis of the protocols takes into account privacy, service precision, and computation and communication
costs, showing the superiority of the new protocols compared to those appeared in the literature to date. The proposed protocols
have also been tested in a full system implementation of the proximity service. 相似文献
80.
Maria Helena L.B. Braz Sean W.M. SiqueiraDiva de S. e S. Rodrigues Rubens N. Melo 《Computers in human behavior》2011,27(4):1344-1351
The development of instructional content using Information Technologies is an expensive, time-consuming and complex process that requires new methodologies. It was in this context that the concept of Learning Objects (LOs) was proposed in order to promote reuse. However, this goal is not yet fully attained and new contributions to increase reuse are still welcome. Besides, if content is conveyed in LOs that are easier to reuse, they must be combined and sequenced in order to build more elaborated and complex content. This paper presents a strategy to deal with these problems based on the definition of small LOs here called Component Objects (COs). These COs are structured and combined according to a conceptual metamodel, which is the basis for the definition of conceptual schemas representing the existing material, including not only content but also practice. This strategy for searching, extracting, and sequencing COs, supports a teacher to better control the implementation of complex content, reducing errors in the authoring process. This approach includes a specification language and an algorithm for semi-automatic sequencing learning content and practice. Finally, a case study that shows the proposed approach and some results of using the algorithm are presented. 相似文献