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We develop a new efficient numerical methodology for automated simultaneous registration and intensity correction of images. The approach separates the intensity correction term from the images being registered in a regularized expression. Our formulation is consistent with the existing non-parametric image registration techniques, however, an extra additive intensity correction term is carried throughout. An objective functional is formed for which the corresponding Hessian and Jacobian is computed and employed in a multi-level Gauss–Newton minimization approach. In this paper, our experiments are based on elastic regularization on the transformation and total variation on the intensity correction. Validations on dynamic contrast enhanced MR abdominal images for both real and simulated data verified the efficacy of the model. 相似文献
33.
An important issue in database (DB) systems is responding to different users’ queries in an acceptable time. To do this, we should define different queries based on users’ real needs and we should consider suitable solutions. In this article, we express a new query called ‘boundary query’ which is used for achieving an overall view of a subject in the DB. This query does not return all query answers but it returns boundary values that cover all answers for the related query. In this article, we map a DB environment to a vector space based on necessary attributes. Then we implement the proposed method, and based on the results, we observe that the proposed method's run time is acceptable for huge DBs. 相似文献
34.
This paper presents a novel improved topology of voltage-fed soft-switching LCrCdc series–parallel quasi-resonant inverter with a constant-frequency for electronic ballast applications. This new topology introduces a low-cost solution to reduce switching losses to achieve high-efficiency ballast. A symmetrical pulse wide modulation (PWM) control scheme is implemented to regulate a wide range of output power. Switching losses effect on ballast efficiency is discussed through experimental point of view. In this discussion, an improved topology in which accomplishes soft-switching operation over a wide power regulation range is proposed. Energy consumption of this new circuit is decreased by using reverse recovery attribute. Additionally, a power-factor correction (PFC) circuit is employed to make the line current follow naturally the sinusoidal line voltage waveform. 相似文献
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36.
The Nuclear Waste Management Organization is evaluating the safety and feasibility of the permanent disposal of used nuclear fuel in a deep geological repository. Their current design concept utilises copper-coated steel used fuel containers to isolate the waste from the environment. Immediately following repository closure, a finite quantity of O2 will be trapped inside the repository and could cause some amount of oxic corrosion to the outer copper layer of the containers. On a per container basis, 13?mol of O2 will be trapped in the repository rooms at the time of closure, based on reference design dimensions. This corresponds to a maximum depth of copper corrosion of 81?μm, assuming a uniform distribution. This work also considers the sensitivity of this oxic corrosion allowance to various hypothetical design changes to the repository that may occur before or during construction. 相似文献
37.
Moradi M Tajik H Razavi Rohani SM Oromiehie AR 《Journal of the science of food and agriculture》2011,91(15):2850-2857
BACKGROUND: The effectiveness of chitosan films containing Zataria multiflora Boiss essential oil (ZEO) (5 and 10 g kg?1) and grape seed extract (GSE) (10 g kg?1) on lipid oxidation and microbial (lactic acid bacteria, aerobic mesophiles and inoculated Listeria monocytogenes) characteristics of mortadella sausage at 4 °C for 21 days was evaluated. The release of total phenolics (TPs) into sausage was also assessed. RESULTS: All films exhibited antibacterial activity against L. monocytogenes on agar culture media. Chitosan films containing ZEO were the most effective on the growth of bacteria. The growth of L. monocytogenes was significantly inhibited by ZEO‐GSE containing films especially during storage of the sausages for 6 days. Aerobic mesophiles and lactic acid bacteria were the most sensitive and resistant groups to films by 0.1–1.1 and 0.1–0.7 log cycles reduction, respectively. Sausages wrapped by 10 g kg?1 GSE + 10 g kg?1 ZEO films had the lowest degrees of lipid oxidation, which was 23% lower than the control. The TPs of ZEO films decreased to zero after 6 days, whereas TPs of GSE films followed a slight decrease during the storage. CONCLUSION: Antimicrobial/antioxidant chitosan film could be developed by incorporating GSE and ZEO for extending the shelf life of mortadella sausage. Copyright © 2011 Society of Chemical Industry 相似文献
38.
Salehebrahimnejad Behnoud Doniavi Ali Moradi Mehran Shahbaz Mehrdad 《Journal of Mechanical Science and Technology》2022,36(10):5117-5124
Journal of Mechanical Science and Technology - III-conditioning at the inverse equation of integral method in ring-core residual stress measurement leads to high stress sensitivity to strain... 相似文献
39.
Falling rock hazard index: a case study from the Marun Dam and power plant, south-western Iran 总被引:1,自引:0,他引:1
Mehran Koleini Jan Louis Van Rooy 《Bulletin of Engineering Geology and the Environment》2011,70(2):279-290
Rock fall phenomena are a major hazard during construction in mountainous regions. At the Marun Dam site, rock falls occur almost every day on the downstream side. The left flank power plant and access roadways as well as the right flank roadways are susceptible to rock falls from the 100?m high cliffs with slopes of 70??0°. The cause is a combination of the orientation of the bedding planes and joint sets and the active tectonic setting of the area. The paper reports the use of RocFall and Dips software to simulate the conditions in order to define the potential risk of rock falls at the Marun Dam site, which could affect workers as well as structures. In the light of the Falling Rock Hazard Index obtained, preventative and remedial measures are suggested. 相似文献
40.
Pejman Mehran Kudret Demirli 《The International Journal of Advanced Manufacturing Technology》2013,67(5-8):1113-1125
This paper describes an automated machine vision-based inspection method for fast and accurate detection of broken edges on the machined surface of water pumps which are formed during casting. The paper proposes a collection of steps to inspect images taken in a noisy environment to identify broken edges. By developing three broken edge verification features and using fuzzy C-means clustering, we provide a fuzzy broken edge inspection model that classifies water pumps into three classes: pumps with significant (major) broken edges, pumps with insignificant (minor) broken edges, and pumps with no broken edges. The devised machine vision-based inspection method is efficient in terms of processing time and accuracy to recognize the parts with broken edges and to make decisions consistent with human knowledge. The fuzzy broken edge detection was carried out on a database of 150 gray-level images. The developed method properly identifies about 95 % of the broken edges in the entire database. 相似文献