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51.
Govindarajan Konda Naganathan Lauren M. Grimes Jeyamkondan Subbiah Chris R. Calkins Ashok Samal George E. Meyer 《Sensing and Instrumentation for Food Quality and Safety》2008,2(3):178-188
Tenderness is a primary determinant of consumer satisfaction of beef steaks. The objective of this study was to implement
and test near-infrared (NIR) hyperspectral imaging to forecast 14-day aged, cooked beef tenderness from the hyperspectral
images of fresh ribeye steaks (n = 319) acquired at 3–5 day post-mortem. A pushbroom hyperspectral imaging system (wavelength range: 900–1700 nm) with a diffuse-flood
lighting system was developed. After imaging, steaks were vacuum-packaged and aged until 14 days postmortem. After aging,
the samples were cooked and slice shear force (SSF) values were collected as a tenderness reference. After reflectance calibration,
a Region-of-Interest (ROI) of 150 × 300 pixels at the center of longissimus muscle was selected. Partial least squares regression (PLSR) was carried out on each ROI image to reduce the dimension along
the spectral axis. Gray-level textural co-occurrence matrix analysis with two quantization levels (64 and 256) was conducted
on the PLSR bands to extract second-order statistical textural features. These features were then used in a canonical discriminant
model to predict three beef tenderness categories, namely tender (SSF ≤ 205.80 N), intermediate (205.80 N < SSF < 254.80 N),
and tough (SSF ≥ 254.80 N). The model with a quantization level of 256 performed better than the one with a quantization level
of 64. This model correctly classified 242 out of 314 samples with an overall accuracy of 77.0%. Fat, protein, and water absorption
bands were identified between 900 and 1700 nm. Our results show that NIR hyperspectral imaging holds promise as an instrument
for forecasting beef tenderness. 相似文献
52.
53.
Michael Spencer Ravinder Garlapalli Jason P. Trembly 《American Institute of Chemical Engineers》2020,66(4):e16887
This study evaluated geochemistry between the Utica-Point Pleasant shale and reservoir/hydraulic fracturing fluid mixtures under simulated reservoir conditions in a batch reactor system. Analytical techniques were utilized to monitor fluid composition with time along with pre- and post-trial shale microscopy and phase identification analyses. Formation of iron-based precipitate was evident through results from fluid and material analyses. Ferrous iron was the predominant iron form found in the aqueous phase, with oxidation to ferric iron and subsequent precipitate formation. Geochemical modeling further supported ferric iron was the favorable phase for precipitation. 相似文献
54.
In the multivariate one-way analysis of variance a test statistic based solely on the rank orders of the data is proposed. In the two group case the statistic simplifies to a test of Puri and Sen [19]. Monte Carlo simulation techniques are used to evaluate the performance of the test statistic under various distributions. These evaluation include the simulated significance levels and power functions. By the nature of the proposed test it is evident that the new procedure is easier to implement than other existing rank based tests. 相似文献
55.
Rajender Prasad Tiwari Vijay Kumar S. Singh Jyoti Shah Ravinder Kumar Kotnala Balaji Birajdar 《Journal of the European Ceramic Society》2018,38(4):1427-1433
In the progress of exploring lead-free ferroelectric perovskites, a new solid solution of is synthesized using solid state method. The effect of Ba and Sc codoping on structural phase transition, dielectric, ferroelectric, electrical, and optical properties is systematically studied. A narrow band gap of 1.98eV is observed at x?=?0.05. On further increase in x, the optical band gap increases due to increased strain. The crystal symmetry changes from orthorhombic at x?=?0.00 to tetragonal phase at x?≤?0.15, remains in pseudocubic phase for 0.15?<?x?<?0.35, and finally transforms to the cubic symmetry at x?≥?0.35. A new Raman active mode evolves at 180? at x?=?0.15, which could be the TO or LO phonon of symmetry. The electrical microstructure of the prepared electroceramics at room temperature has been investigated using impedance spectroscopy. This newly synthesized ferroelectric perovskite material has promising potential applications for photocatalysis and photovoltaics, especially under the visible light spectrum. 相似文献
56.
D. Ravinder K. Sathi Reddy P. Mahesh T. Bhaskar Rao Y.C. Venudhar 《Journal of Alloys and Compounds》2004,370(1-2):L17-L22
Electrical conductivity of copper–chromium (Cu–Cr) ferrites of various compositions have been investigated as a function of composition and temperature. Plots of log (σT) versus 103/T are almost linear and have shown a transition near the Curie temperature. The activation energy in the ferrimagnetic region is in general less than that in the paramagnetic region. An attempt is made to explain the conduction mechanism in Cu–Cr ferrites. 相似文献
57.
In this paper a new design is proposed in microstrip antenna family. In this paper, a review design of microstrip antenna design using particle swarm optimization (PSO) and advanced particle swarm optimization (APSO) has been presented which optimizes the parameters and both results are compared. This technique helps antenna engineers to design, analyze, and simulate antenna efficiently and effectively. An advanced PSO driven antenna has been developed to calculate resonant frequency of slit-cut stacked equilateral triangular microstrip antenna. The paper presents simplicity, accuracy and comparison of result between PSO and APSO. 相似文献
58.
Sivasubramanian Geetha Konda Kannan Satheesh Kumar Dinesh Chandra Trivedi 《应用聚合物科学杂志》2005,96(6):2316-2323
A method to enhance the electronic conductivity of polyaniline grafted E‐glass fabric is described. The influence of substituted aromatic sulfonic acids as primary dopants on conductivity of the grafted polyaniline–E‐glass fabrics is studied. The conducting fabrics obtained in this method were characterized by UV‐vis spectroscopy, scanning electron microscopy, X‐ray diffraction study, thermogravimetric analysis, and conductivity. Shielding effectiveness measurements on these Pan–E‐glass fabrics showed that the performance is improved (i.e., 0.01 MHz = 49 dB, 1000 MHz = 7 dB) compared to earlier studies (i.e., 0.05 MHz = 37 dB, 1000 MHz = 1 dB) without pretreatment of fabrics. Possible application of these fabrics, e.g., for dissipation of electrostatic charge, is suggested. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2316–2323, 2005 相似文献
59.
60.
Singh Ravi Pratap Kataria Ravinder Singhal Sandeep Garg R. K. Tyagi Mohit 《SILICON》2020,12(11):2587-2600
Silicon - The silicon dioxide (i.e. quartz) has been finely viewed as one of the exceedingly claimed contemporary ceramics which is getting broad engineering applications owing to its superior and... 相似文献