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排序方式: 共有486条查询结果,搜索用时 15 毫秒
11.
This paper presents numerical investigation of the influence of the specimen geometry, loading condition, size-effect and softening function of concrete on double-K fracture parameters. The input data needed for computation of the double-K fracture parameters are obtained from the well-known version of Fictitious Crack Model (FCM). FCM is developed for three standard specimens: three-point bend test, compact tension specimen and four-point bend test of size range 100–600 mm at relative size of initial crack length 0.3. The analysis of numerical results shows some interesting behaviour of double-K fracture parameters. 相似文献
12.
13.
The need for a general purpose Content Based Image Retrieval (CBIR) system for huge image databases has attracted information-technology researchers and institutions for CBIR techniques development. These techniques include image feature extraction, segmentation, feature mapping, representation, semantics, indexing and storage, image similarity-distance measurement and retrieval making CBIR system development a challenge. Since medical images are large in size running to megabits of data they are compressed to reduce their size for storage and transmission. This paper investigates medical image retrieval problem for compressed images. An improved image classification algorithm for CBIR is proposed. In the proposed method, RAW images are compressed using Haar wavelet. Features are extracted using Gabor filter and Sobel edge detector. The extracted features are classified using Partial Recurrent Neural Network (PRNN). Since training parameters in Neural Network are NP hard, a hybrid Particle Swarm Optimization (PSO) – Cuckoo Search algorithm (CS) is proposed to optimize the learning rate of the neural network. 相似文献
14.
EFFECT OF COMBINATION DRYING ON THE PHYSICO-CHEMICAL CHARACTERISTICS OF CARROT AND PUMPKIN 总被引:3,自引:0,他引:3
H. S. PHANINDRA KUMAR K. RADHAKRISHNA P. K. NAGARAJU D. VIJAYA RAO 《Journal of Food Processing and Preservation》2001,25(6):447-460
The quality of dehydrated carrot and pumpkin pieces produced by combination drying employing partial freeze-drying and hot air-drying were investigated. The drying rate, the total energy requirement and the physico-chemical properties of the combination dried (CD) products were compared with those of hot air-dried (HAD) and freeze-dried (FD) products. The total carotenoid content of the two vegetables (1050 ppm and 160 ppm) was significantly affected by drying processes. Destruction of carotenoids during storage at different temperatures was less in the CD samples. The HAD vegetables exhibited shrinkage, case hardening and poor rehydration (25 and 28 min in cold water, rehydration ratio 1:2.6 and 1:2.9, respectively). The FD vegetables appeared wholesome, porous, well formed with excellent rehydration features at room temperature (rehydration time 2 and 3 min in cold water, rehydration ratio 1:7 and 1:6.9, respectively). The CD vegetables were comparatively superior to HAD products and were nearer in quality to FD products with respect to appearance, rehydration (9 and 10 min in cold water, rehydration ratio 1:5 and 1:4, respectively). The drying time and total energy for CD processing was 50% less than for FD but similar to HAD. The combination dehydration process is effective in obtaining high quality dehydrated vegetables. 相似文献
15.
NAGAPPA S. KARABASANAVAR S.P. SINGH UMAPATHI V. DEEPAK KUMAR SUNIL N. SHEBANNAVAR 《Journal of food quality》2011,34(2):142-149
ABSTRACT
A highly species‐specific polymerase chain reaction (PCR) assay was developed for the authentic identification of goat. A product of 436 bp was amplified using newly designed primers against mitochondrial D‐loop region. The possibility of cross‐amplification was ruled out by considering as many as 25 other animal species. Suitability of the developed goat species‐specific PCR assay was confirmed for in raw, cooked (60, 80 and 100C for 30 min) and micro‐oven‐processed meat samples (n = 20 each). A sensitivity of 0.1% was established for detection of adulteration and limit of detection of goat DNA was 0.1 pg. This investigation presents a novel PCR assay with its newly designed primers that could be used for the authentic identification of goat species.PRACTICAL APPLICATIONS
This work details about a novel diagnostic polymerase chain reaction, which could be used for authentic identification of goat species. This approach could be used for the confirmation of goat tissues in raw, cooked, as well as adulterated samples. The developed technique has also applications in the forensic analysis of wild animal‐related disputes, where this work could solve the problem of goat‐related issues. 相似文献16.
Frequency regulation in a generation mix having large wind power penetration is a critical issue, as wind units isolate from the grid during disturbances with advanced power electronics controllers and reduce equivalent system inertia. Thus, it is important that wind turbines also contribute to system frequency control. This paper examines the dynamic contribution of doubly fed induction generator (DFIG)-based wind turbine in system frequency regulation. The modified inertial support scheme is proposed which helps the DFIG to provide the short term transient active power support to the grid during transients and arrests the fall in frequency. The frequency deviation is considered by the controller to provide the inertial control. An additional reference power output is used which helps the DFIG to release kinetic energy stored in rotating masses of the turbine. The optimal speed control parameters have been used for the DFIG to increases its participation in frequency control. The simulations carried out in a two-area interconnected power system demonstrate the contribution of the DFIG in load frequency control. 相似文献
17.
G.V.V. SURYA KIRAN K. HARI KRISHNA Sk. SAMEER M. BHARGAVI B. SANTOSH KUMAR G. MOHANA RAO Y. NAIDUBABU RAVIKUMAR DUMPALA B. RATNA SUNIL 《中国有色金属学会会刊》2017,27(4):804-811
AZ91 Mg alloy was considered and friction stir processing (FSP) was adopted to achieve grain refinement to investigate the effect of grain size and secondary phase on machining characteristics during drilling at various speeds and feeds. Super saturated AZ91 Mg alloy was obtained after FSP and the grain refinement was achieved from (166.5±8.7) µm to (21.7±13.5) µm. Surprisingly, hardness reduced for FSP AZ91 Mg alloy (88.95±6.1) compared with AZ91 alloy (108.2±15.6), which was attributed to the reduced secondary phase. However, the mean cutting force for FSP-treated (FSPed) AZ91 Mg alloy was marginally increased. The edge damage of the drilled holes was lower for FSPed AZ91 Mg alloy compared with unprocessed AZ91 Mg alloy. Hence, it can be understood that the grain refinement may slightly increase the cutting forces during drilling but better edge finishing can be achieved in machining of AZ91 Mg alloy. 相似文献
18.
The objective of this work is to study the cryogenic sheet metal forming behaviour of precipitation hardening AW-6016-T4. In this regard, the flow curves and forming limit curves were obtained by tension and Nakazima experimental testing methods in the temperature ranges from ?196 to 25 °C. It was found that strength and elongation increase with decreasing temperature. Small but perceived differences between microstructure of the material deformed at the room and cryogenic temperatures respectively were identified by electron backscatter diffraction (EBSD) analysis. However, no significant difference in the precipitation kinetics during continuous heating in the DSC has been observed. This study has demonstrated the potential of cryogenic forming by manufacturing a B-pillar part with 8 mm depth of side design element as compared to 6 mm at room temperature. 相似文献
19.
Toned dairy milk and soy milk were mixed in different proportions and coagulated at various temperatures to produce paneer blends, and their textural properties were evaluated. As the soy milk proportion in the blend increased from 0% to 50%, hardness, cohesiveness and chewiness of the samples decreased initially, but further increase in the blend from 50% to 100% cause these values to increase slightly. The proportion of soymilk in the prepared paneer had a significant effect on hardness, cohesiveness, adhesiveness, chewiness and yield, whereas the coagulation temperature affected cohesiveness and yield. The process parameters did not show any effect on the springiness. 相似文献
20.
Tamara Sumner Faisal Ahmad Sonal Bhushan Qianyi Gu Francis Molina Stedman Willard Michael Wright Lynne Davis Greg Janée 《International Journal on Digital Libraries》2005,5(1):18-24
Concept browsing interfaces can help educators and learners to locate and use learning resources that are aligned with recognized learning goals. The Strand Map Service enables users to navigate interactive visualizations of related learning goals and to request digital library resources aligned with learning goals. These interfaces are created using a programmatic Web service interface that dynamically generates interactive visual components. Preliminary findings suggest that these library interfaces appear to help users stay focused on the scientific content of their information discovery task, as opposed to focusing on the mechanics of searching. 相似文献