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1.
Linear pose estimation from points or lines   总被引:10,自引:0,他引:10  
Estimation of camera pose from an image of n points or lines with known correspondence is a thoroughly studied problem in computer vision. Most solutions are iterative and depend on nonlinear optimization of some geometric constraint, either on the world coordinates or on the projections to the image plane. For real-time applications, we are interested in linear or closed-form solutions free of initialization. We present a general framework which allows for a novel set of linear solutions to the pose estimation problem for both n points and n lines. We then analyze the sensitivity of our solutions to image noise and show that the sensitivity analysis can be used as a conservative predictor of error for our algorithms. We present a number of simulations which compare our results to two other recent linear algorithms, as well as to iterative approaches. We conclude with tests on real imagery in an augmented reality setup.  相似文献   
2.
This article describes the development, optimization, and evaluation of Carbopol 940 topical gel containing aceclofenac-crospovidone (1:4) solid dispersion using “Quality by Design (QbD)” approach based on 23 factorial design. The effect of crospovidone, tri-ethanolamine, and ethyl alcohol amount on the drug permeation profile of the topical gel containing aceclofenac-crospovidone solid dispersion was optimized by 23 factorial design. The optimized gel showed improved permeation profile with cumulative drug permeation of 26.262 ± 2.157%, and permeation flux of 0.059 ± 0.011 μg/cm2/h. These gels were characterized by pH, viscosity, gel strength and FTIR study. The in vivo anti-inflammatory activity of the optimized gel was evaluated in rats using carrageenan-induced rat-paw oedema model and found excellent anti-inflammatory comparable with a marketed gel without producing any skin irritation.  相似文献   
3.
Gated spillways are used to control flow in canals, rivers, and estuaries. Despite their widespread use, available flow ratings at these gated structures are largely derived from reduced-scale laboratory models. In this paper, generalized flow rating equations are developed based on field flow measurements collected mostly with an Acoustic Doppler Current Profiler at about 90 prototype gated spillways in South Florida. The proposed ratings, developed using dimensional analysis, agree well with field measurements. A single generalized equation that is applicable to all flow conditions was also developed. This generalized equation addresses the limitation of continuity of the calculations as flow transitions from one condition to another.  相似文献   
4.
This paper develops a model to explain the ‘energy paradox,’ the inclination of households and firms to require very high internal rates of return in order to make energy-saving investments. The model abstracts from many features of such investments to focus on their irreversibility, the uncertainty of their future payoff streams, and the investor's anticipation of future technological advance. In this setting, the decision to invest in energy-saving technology can be delayed, providing option value. In addition, delay allows the potential investor to cash in on future experience-curve effects: With the passage of time, firms gain practical knowledge in producing and installing the energy-saving technology, enabling them to reduce the technology's up-front cost per unit of energy saved. We incorporate these fundamentals into a stochastic model where the investment's discounted benefits follow geometric Brownian motion. To demonstrate the model's capabilities, we generate simulation results for photovoltaic systems that highlight the experience-curve effect as a fundamental reason why households and firms delay making energy-saving investments until internal rates of return exceed values of 50% and higher, consistent with observations in the economics literature. We also explore altruistic motivations for energy conservation and the model's implications for both “additionality” and the design of energy-conservation policy.  相似文献   
5.
Oxidation resistance and water wettability of graphite flakes have been improved by a thin sol–gel film of magnesium aluminate spinel (MgAl2O4) over its surface. The hydrosol has been synthesized by less expensive precursors and the spinel formation has been studied by scanning electron microscopy (SEM), supplemented with energy dispersive spectral analysis. After an easy-to-use mixing procedure, drying (110°C), and subsequent calcination (550°C), coated graphites were sieved to below 75 μm. The coating over the powder contained 1.5 wt% MgAl2O4, which enormously increased the oxidation resistance (performed at 600°, 900°, and 1200°C) and water wettability, as revealed by hydrophilic functional groups from infrared spectra. Defective, intermediate spinel structure of fine, lamellar Mg-doped γ-Al2O3 has been considered to be significant for this improvement. An approximate (1:2) stoichiometry of (Mg:Al) in the coating composition was confirmed by an X-ray photoelectron spectroscopy test. Castables prepared by this graphite remarkably improved their bulk density and apparent porosity compared with those prepared by the as-received graphite. Casting water was reduced along with the amount of antioxidants. This also enhanced the resistance toward the basic slag by retaining the graphite in the refractory.  相似文献   
6.
Modeling strategies of 3D woven composites: A review   总被引:1,自引:0,他引:1  
Due to advancements made in 3D weaving process, 3D woven composites have evolved as an attractive structural material for multi-directional load bearing and impact applications, due to their unique transverse properties such as stiffness, strength, fracture toughness and damage resistance. Substantial progress has been made in recent years for the development of new modeling techniques in design and analysis to understand the unique mechanical behavior of 3D woven composites. This paper systematically reviews the modeling techniques along with their capabilities and limitations for characterization of the micro-geometry, mechanical/thermo-mechanical behavior and impact behavior of 3D woven composites. Advantages, disadvantages and applications of 3D woven composites have also been delineated. In addition, this reference list provides a good database for future research on 3D woven composites.  相似文献   
7.
Tuna in oil was processed in retort pouches (20 × 17 cm) to a, F0 value of 10. Heat penetration characteristics were determined using a rotary retort to an F0 value of 10 and the results compared with a stationary retort. For studying the changes in heat penetration during rotation, tuna in oil was packed into retort pouches, subjected to different rotation speeds (2, 4 and 6 r.p.m.) and thermally processed to the same F0 value. For the same F0 value of 10, although there was a reduction in process time with increasing rotation speed up to 6 r.p.m., the magnitude of the reduction in processing time decreased with increase in speed of rotation. However up to 2 r.p.m. there was a considerable reduction in process time.  相似文献   
8.
9.
Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti‐oxidant, anti‐coagulant, anti‐thrombotic, anti‐cancer and immune‐stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry  相似文献   
10.
Immunological, clinical, and pathological investigations were conducted on a horse with lymphosarcoma. The immunological status was investigated by measuring the level of antibodies by single radial immunodiffusion test and the ability of lymphocytes to proliferate in response to mitogens. Multiple immunological abnormalities were noted in this horse. They were; (1) decreased IgM, IgG, and IgA levels in the serum despite hyperproteinemia; (2) increased in-vitro spontaneous lymphoproliferation which reflects augmented mitosis; (3) decreased lymphoproliferative response to T cell stimulants (e.g. Concanavalin-A (Con-A)) suggesting impaired T cell activation; (4) presence of immunosuppressive factors in serum as demonstrated by in-vitro lymphocyte culture systems. Clinical pathology findings revealed an unusual monoclonal alpha peak in the serum and morphologically abnormal lymphocytes distributed throughout the body. Serum fractionated by fast protein liquid chromatography (FPLC) revealed that the immunosuppressive factors were found in this abnormal alpha peak. The immunopathological findings in this horse are discussed.  相似文献   
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