The visible/near-infrared spectra of 300 chicken livers were analyzed to explore the feasibility of using spectroscopy to separate septicemic livers from normal livers. Three strategies involving offset, second difference, and functional link methods were applied to preprocess the spectra, while principal component analysis (PCA) was utilized to reduce the input data dimensions. PCA scores were fed into a feed-forward back-propagation neural network for classification. The results showed no obvious difference in classification accuracy between offset and non-offset data when no other preprocessing method was applied. The full 400-2498 nm wavelength region produced better results than the 400-700 nm, 400-1098 nm, and 1102-2498 nm sub-regions when more than 30 PCA scores were used. In general, the classification accuracy was improved by increasing the number of scores of input data, but too many scores diminished performance. The functional link test showed that using functional-link spectra selected at every third point with 60 scores achieved the same classification accuracy as that obtained when using all the data points with 90 scores. The best classification model used offset correction followed by second difference (g = 31) and 60 scores. It achieved a classification accuracy of 98% for normal and 94% for septicemic livers.

To establish a procedure for differentiating normal chickens from chickens with septicemia/toxemia (septox) by machine inspection under the Hazard Analysis and Critical Control Point-Based Inspection Models Project, spectral measurements of 300 chicken livers, of which half were normal and half were condemned due to septox conditions, were collected and analyzed. Neural network classification of the spectral data after principal component analysis (PCA) indicated that normal and septox livers were correctly differentiated by spectroscopy at a rate of 96%. Analysis of the data established 100% correlation between the spectroscopic identification and the subset of samples, both normal and septox, that were histopathologically diagnosed. In an attempt to establish the microbiological etiology of the diseased livers, isolates from 30 livers indicated that the poultry carcasses were contaminated mostly with coliforms present in the environment, hindering the isolation of pathogenic microorganisms. Therefore, to establish the cause of diseased livers, a strictly aseptic environment and procedure for sample collection is required.

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With the characteristics of higher electron density and lower ion bombardment energy, large-area VHF (very high frequency) plasma enhanced chemical vapor deposition has become an essential manufacturing equipment to improve the production throughput and efficiency of thin film silicon solar cell. However, the combination of high frequency and large electrodes leads to the so-called standing wave effect causing a serious problem for the deposition uniformity of silicon thin film. In order to address this issue, a technique based on the idea of simultaneously launching two standing waves that possess similar amplitudes and are out of phase by 90° in time and space is proposed in this study. A linear plasma reactor with discharge length of 54 cm is tested with two different frequencies including 60 and 80 MHz. The experimental results show that the proposed technique could effectively improve the non-uniformity of VHF plasmas from >±60% when only one standing wave is applied to <±10% once two specific standing waves are launched at the same time. Moreover, in terms of the reactor configuration adopted in this study, in which the standing wave effect along the much shorter dimension can be ignored, the proposed technique is applicable to different frequencies without the need to alter the number and arrangement of power feeding points.