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61.
This paper documents the design, competing systems, results, and conclusions of the CADE-14 ATP System Competition (CASC-14). 相似文献
62.
NB Modi YS Lin T Reynolds A Shaheen BJ Christian 《Canadian Metallurgical Quarterly》1998,32(3):397-405
OBJECTIVE: The study aimed to determine the effectiveness of prophylactic medical intervention in reducing the incidence of cystoid macular edema (CME) and the effectiveness of medical treatment for chronic CME after cataract surgery. DESIGN: The study design was a systematic review and meta-analysis of published reports of randomized clinical trials (RCTs). PARTICIPANTS: Sixteen RCTs involving 2898 eyes examining the effectiveness of medical prophylaxis of CME and 4 RCTs involving 187 eyes testing the effectiveness of medical treatment of chronic CME were used in the study. INTERVENTIONS: Medical prophylaxis of treatment (cyclo-oxygenase inhibitors or corticosteroids) versus control (placebo or active treatment) was performed. MAIN OUTCOME MEASURES: Incidence of angiographically diagnosed CME, incidence of clinically significant CME, and vision were measured. RESULTS: Thirty-six articles reported testing a prophylactic medical intervention for CME after cataract surgery. The incidence of CME varied extensively across studies and was related to the study design used. Summary odds ratios (OR) indicated that prophylactic intervention was effective in reducing the incidence of both angiographic CME (OR = 0.36; 95% confidence interval [CI] = 0.28-0.45) and clinically relevant CME (OR = 0.49; 95% CI = 0.33-0.73). There also was a statistically significant positive effect on improving vision (OR = 1.97; 95% CI = 1.14-3.41). A combination of the results of the four RCTs testing medical therapy for chronic CME indicated a treatment benefit in terms of improving final visual acuity by two or more Snellen lines (OR = 2.67; 95% CI = 1.35-5.30). Assessment of the quality of the 20 RCTs included in the meta-analyses indicated problems in the design, execution, and reporting of a number of trials. CONCLUSION: A combination of the results from RCTs indicates that medical prophylaxis for aphakic and pseudophakic CME and medical treatment for chronic CME are beneficial. Because most of the RCTs performed to date have problems related to quality, a well-designed RCT is needed to confirm this result, using clinical CME and vision as outcomes. 相似文献
63.
An Extended Replication of an Experiment for Assessing Methods for Software Requirements Inspections 总被引:1,自引:1,他引:0
Kristian Sandahl Ola Blomkvist Joachim Karlsson Christian Krysander Mikael Lindvall Niclas Ohlsson 《Empirical Software Engineering》1998,3(4):327-354
We have performed an extended replication of the Porter-Votta-Basili experiment comparing the Scenario method and the Checklist method for inspecting requirements specifications using identical instruments. The experiment has been conducted in our educational context represented by a more general definition of a defect compared to the original defect list. Our study involving 24 undergraduate students manipulated three independent variables: detection method, requirements specification, and the order of the inspections. The dependent variable measured is the defect detection rate. We found the requirements specification inspected and not the detection method to be the most probable explanation for the variance in defect detection rate. This suggests that it is important to gather knowledge of how a requirements specification can convey an understandable view of the product and to adapt inspection methods accordingly. Contrary to the original experiment, we can not significantly support the superiority of the Scenario method. This is in accordance with a replication conducted by Fusaro, Lanubile and Visaggio, and might be explained by the lack of individual defect detection skill of our less experienced subjects. 相似文献
64.
Christian Thaulow Øyvind Ranestad Mons Hauge Zhiliang Zhang Masao Toyoda Fumiyoshi Minami 《Engineering Fracture Mechanics》1997,57(6):637-651
This paper investigates the stress fields for a crack located at the fusion line of a weldment. The strength mis-matching and the size of the HAZ were varied, and the corresponding distribution of the maximum principal stress was examined. The weld metal strength was globally overmatched with respect to the base material, but locally over- and undermatched with respect to the heat affected zone. Three cases of mis-match were compared, and it was found that reducing the strength of the HAZ lowered the maximum principal stresses. 相似文献
65.
Elena Andreeva Andrey Bogdanov Bart Mennink Bart Preneel Christian Rechberger 《International Journal of Information Security》2012,11(2):103-120
In 2007, the US National Institute for Standards and Technology (NIST) announced a call for the design of a new cryptographic
hash algorithm in response to vulnerabilities like differential attacks identified in existing hash functions, such as MD5
and SHA-1. NIST received many submissions, 51 of which got accepted to the first round. 14 candidates were left in the second
round, out of which five candidates have been recently chosen for the final round. An important criterion in the selection
process is the SHA-3 hash function security. We identify two important classes of security arguments for the new designs:
(1) the possible reductions of the hash function security to the security of its underlying building blocks and (2) arguments
against differential attack on building blocks. In this paper, we compare the state of the art provable security reductions
for the second round candidates and review arguments and bounds against classes of differential attacks. We discuss all the
SHA-3 candidates at a high functional level, analyze, and summarize the security reduction results and bounds against differential
attacks. Additionally, we generalize the well-known proof of collision resistance preservation, such that all SHA-3 candidates
with a suffix-free padding are covered. 相似文献
66.
On July 24, 2010, 21 people died and more than 500 were injured in a stampede at the Loveparade, a music festival, in Duisburg, Germany. Although this tragic incident is but one among many terrible crowd disasters that occur during pilgrimage, sports events, or other mass gatherings, it stands out for it has been well documented: there were a total of seven security cameras monitoring the Loveparade and the chain of events that led to disaster was meticulously reconstructed.In this paper, we present an automatic, video-based analysis of the events in Duisburg. While physical models and simulations of human crowd behavior have been reported before, to the best of our knowledge, automatic vision systems that detect congestions and dangerous crowd turbulences in real world settings were not reported yet. Derived from lessons learned from the video footage of the Loveparade, our system is able to detect motion patterns that characterize crowd behavior in stampedes. Based on our analysis, we propose methods for the detection and early warning of dangerous situations during mass events. Since our approach mainly relies on optical flow computations, it runs in real-time and preserves privacy of the people being monitored. 相似文献
67.
O'Reilly C Plamondon R 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2012,42(5):1428-1442
Fast reaching movements are an important component of our daily interaction with the world and are consequently under investigation in many fields of science and engineering. Today, useful models are available for such studies, with tools for solving the inverse dynamics problem involved by these analyses. These tools generally provide a set of model parameters that allows an accurate and locally optimal reconstruction of the original movements. Although the solutions that they generate may provide a data curve fitting that is sufficient for some pattern recognition applications, the best possible solution is often necessary in others, particularly those involving neuroscience and biomedical signal processing. To generate these solutions, we present a globally optimal parameter extractor for the delta-lognormal modeling of reaching movements based on the branch-and-bound strategy. This algorithm is used to test the impact of white noise on the delta-lognormal modeling of reaching movements and to benchmark the state-of-the-art locally optimal algorithm. Our study shows that, even with globally optimal solutions, parameter averaging is important for obtaining reliable figures. It concludes that physiologically derived rules are necessary, in addition to global optimality, to achieve meaningful ?Λ extractions which can be used to investigate the control patterns of these movement primitives. 相似文献
68.
Clones are generally considered bad programming practice in software engineering folklore. They are identified as a bad smell?(Fowler et?al. 1999) and a major contributor to project maintenance difficulties. Clones inherently cause code bloat, thus increasing project size and maintenance costs. In this work, we try to validate the conventional wisdom empirically to see whether cloning makes code more defect prone. This paper analyses the relationship between cloning and defect proneness. For the four medium to large open source projects that we studied, we find that, first, the great majority of bugs are not significantly associated with clones. Second, we find that clones may be less defect prone than non-cloned code. Third, we find little evidence that clones with more copies are actually more error prone. Fourth, we find little evidence to support the claim that clone groups that span more than one file or directory are more defect prone than collocated clones. Finally, we find that developers do not need to put a disproportionately higher effort to fix clone dense bugs. Our findings do not support the claim that clones are really a “bad smell”?(Fowler et?al. 1999). Perhaps we can clone, and breathe easily, at the same?time. 相似文献
69.
David Damm Christian Fremerey Verena Thomas Michael Clausen Frank Kurth Meinard Müller 《International Journal on Digital Libraries》2012,12(2-3):53-71
In this paper, we present a digital library system for managing heterogeneous music collections. The heterogeneity refers to various document types and formats as well as to different modalities, e. g., CD-audio recordings, scanned sheet music, and lyrics. The system offers a full-fledged, widely automated document processing chain: digitization, indexing, annotation, access, and presentation. Our system is implemented as a generic and modular music repository based on a service-oriented software architecture. As a particular strength of our approach, the various documents representing aspects of a piece of music are jointly considered in all stages of the document processing chain. Our user interfaces allow for a multimodal and synchronized presentation of documents (WYSIWYH: what you see is what you hear), a score- or lyrics-based navigation in audio, as well as a cross- and multimodal retrieval. Hence, our music repository may be called a truly cross-modal library system. In our paper, we describe the system components, outline the techniques of the document processing chain, and illustrate the implemented functionalities for user interaction. We describe how the system is put into practice at the Bavarian State Library (BSB) Munich as a part of the German PROBADO Digital Library Initiative (PDLI). 相似文献
70.
Given an undirected, vertex-weighted graph, the goal of the minimum weight vertex cover problem is to find a subset of the vertices of the graph such that the subset is a vertex cover and the sum of the weights of its vertices is minimal. This problem is known to be NP-hard and no efficient algorithm is known to solve it to optimality. Therefore, most existing techniques are based on heuristics for providing approximate solutions in a reasonable computation time.Population-based search approaches have shown to be effective for solving a multitude of combinatorial optimization problems. Their advantage can be identified as their ability to find areas of the space containing high quality solutions. This paper proposes a simple and efficient population-based iterated greedy algorithm for tackling the minimum weight vertex cover problem. At each iteration, a population of solutions is established and refined using a fast randomized iterated greedy heuristic based on successive phases of destruction and reconstruction. An extensive experimental evaluation on a commonly used set of benchmark instances shows that our algorithm outperforms current state-of-the-art approaches. 相似文献