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71.
Kaindl AM Zabel C Stefovska V Lehnert R Sifringer M Klose J Ikonomidou C 《Proteomics. Clinical applications》2007,1(7):640-649
Traumatic brain injury (TBI) is a major cause of morbidity and mortality among children and adolescents. To gain insight into developmental events influenced by TBI, we analyzed subacute mouse brain proteome changes in a percussion head trauma model at P7 ipsi- and contralateral to the site of injury. The comparison of brain proteomes of trauma mice and controls revealed reproducible changes in the intensity of 28 proteins (30 protein spots) in response to trauma. The changes detected suggest that TBI leads to apoptosis, inflammation, and oxidative stress. These changes were consistent with our results of histological and biochemical evaluation of the brains which revealed widespread apoptotic neurodegeneration, microglia activation, and increased levels of protein carbonyls. Furthermore, we detected changes in proteins involved in neuronal migration as well as axonal and dendritic growth and guidance, suggesting interference of trauma with these developmental events. 相似文献
72.
Levi Valgaerts Andrés Bruhn Markus Mainberger Joachim Weickert 《International Journal of Computer Vision》2012,96(2):212-234
There are two main strategies for solving correspondence problems in computer vision: sparse local feature based approaches
and dense global energy based methods. While sparse feature based methods are often used for estimating the fundamental matrix
by matching a small set of sophistically optimised interest points, dense energy based methods mark the state of the art in
optical flow computation. The goal of our paper is to show that this separation into different application domains is unnecessary
and can be bridged in a natural way. As a first contribution we present a new application of dense optical flow for estimating
the fundamental matrix. Comparing our results with those obtained by feature based techniques we identify cases in which dense
methods have advantages over sparse approaches. Motivated by these promising results we propose, as a second contribution,
a new variational model that recovers the fundamental matrix and the optical flow simultaneously as the minimisers of a single
energy functional. In experiments we show that our coupled approach is able to further improve the estimates of both the fundamental
matrix and the optical flow. Our results prove that dense variational methods can be a serious alternative even in classical
application domains of sparse feature based approaches. 相似文献
73.
74.
Joachim Pistorius & Michel Minoux 《International Transactions in Operational Research》2003,10(1):1-11
Algorithms described so far to solve the maximum flow problem on hypergraphs first necessitate the transformation of these hypergraphs into directed graphs. The resulting maximum flow problem is then solved by standard algorithms. This paper describes a new method that solves the maximum flow problem directly on hypergraphs, leading to both reduced run time and lower memory requirements. We compare our approach with a state–of–the–art algorithm that uses a transformation of the hypergraph into a directed graph and an augmenting path algorithm to compute the maximum flow on this directed graph: the run–time complexity as well as the memory space complexity are reduced by a constant factor. Experimental results on large hypergraphs from VLSI applications show that the run time is reduced, on average, by a factor approximately 2, while memory occupation is reduced, on average, by a factor of 10. This improvement is particularly interesting for very large instances, to be solved in practical applications. 相似文献
75.
An autonomous mobile robot with a 3D laser range finder for 3D exploration and digitalization of indoor environments 总被引:8,自引:0,他引:8
Digital 3D models of the environment are needed in rescue and inspection robotics, facility managements and architecture. This paper presents an automatic system for gaging and digitalization of 3D indoor environments. It consists of an autonomous mobile robot, a reliable 3D laser range finder and three elaborated software modules. The first module, a fast variant of the Iterative Closest Points algorithm, registers the 3D scans in a common coordinate system and relocalizes the robot. The second module, a next best view planner, computes the next nominal pose based on the acquired 3D data while avoiding complicated obstacles. The third module, a closed-loop and globally stable motor controller, navigates the mobile robot to a nominal pose on the base of odometry and avoids collisions with dynamical obstacles. The 3D laser range finder acquires a 3D scan at this pose. The proposed method allows one to digitalize large indoor environments fast and reliably without any intervention and solves the SLAM problem. The results of two 3D digitalization experiments are presented using a fast octree-based visualization method. 相似文献
76.
This article describes an evaluation of six different methods for prioritizing software requirements. Based on the quality requirements for a telephony system, the authors individually used all six methods on separate occasions to prioritize the requirements. The methods were then characterized according to a number of criteria from a user's perspective. We found the analytic hierarchy process to be the most promising method, although it may be problematic to scale-up. In an industrial follow-up study we used the analytic hierarchy process to further investigate its applicability. We found that the process is demanding but worth the effort because of its ability to provide reliable results, promote knowledge transfer and create consensus among project members. 相似文献
77.
An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments.
This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements
according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are
suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed.
A support tool for the improved process has been developed to make the process more practical in commercial developments.
The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems
AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is
an important step in that direction. 相似文献
78.
Commercially produced 0.03 % C, 0.08 % Nb, 0.01 % Ti high strength low alloyed (HSLA) steel in the form of 20 mm thick plates was investigated. The steel was thermomechanically processed and the mechanical properties of the steel were evaluated by tensile testing. Using analytical and high resolution transmission electron microscopy the distribution, morphology, composition, crystal structure and particle size of niobium and titanium carbonitrides were observed and identified in these steels. The distribution of the precipitates was found to be nearly random, with occasional occurrence of precipitation free zones. Complex agglomerates with a cubic TiN seed crystal overgrown by a cubic NbC particle were the most commonly observed precipitates. Further TEM analysis in the accelerated cooled and tempered specimens in 1/4 plate thickness did not reveal any evidence that additional precipitation in the ferrite occurred. Precipitation in ferrite was only detected after subsequent cold deformation and tempering of the same samples. By a combination of EFTEM, STEM, HRTEM in addition to EDX spectroscopy, a large population of strain induced NbC precipitates with fcc crystal structure ranging in size down to 2 nm were identified in the ferrite matrix. 相似文献
79.
Pedersoli E Capotondi F Cocco D Zangrando M Kaulich B Menk RH Locatelli A Mentes TO Spezzani C Sandrin G Bacescu DM Kiskinova M Bajt S Barthelmess M Barty A Schulz J Gumprecht L Chapman HN Nelson AJ Frank M Pivovaroff MJ Woods BW Bogan MJ Hajdu J 《The Review of scientific instruments》2011,82(4):043711
We present a compact modular apparatus with a flexible design that will be operated at the DiProI beamline of the Fermi@Elettra free electron laser (FEL) for performing static and time-resolved coherent diffraction imaging experiments, taking advantage of the full coherence and variable polarization of the short seeded FEL pulses. The apparatus has been assembled and the potential of the experimental setup is demonstrated by commissioning tests with coherent synchrotron radiation. This multipurpose experimental station will be open to general users after installation at the Fermi@Elettra free electron laser in 2011. 相似文献
80.
Plasmaprimer — functional coatings for adhesion improvement When replacing solvent based paint or adhesion promoter partly new production processes are necessary. Plasma enhanced chemical vapor deposition offers to change the surface characteristics of parts according to the necessities of the following application. At the same time improvements in adhesion, in handling and environmental compatibility can be achieved. In this article an according production method is described and perspectives of new developments are shown. 相似文献