This paper presents an extension of our previous work which proposes a new speaker representation for speaker verification. In this modeling, a new low-dimensional speaker- and channel-dependent space is defined using a simple factor analysis. This space is named the total variability space because it models both speaker and channel variabilities. Two speaker verification systems are proposed which use this new representation. The first system is a support vector machine-based system that uses the cosine kernel to estimate the similarity between the input data. The second system directly uses the cosine similarity as the final decision score. We tested three channel compensation techniques in the total variability space, which are within-class covariance normalization (WCCN), linear discriminate analysis (LDA), and nuisance attribute projection (NAP). We found that the best results are obtained when LDA is followed by WCCN. We achieved an equal error rate (EER) of 1.12% and MinDCF of 0.0094 using the cosine distance scoring on the male English trials of the core condition of the NIST 2008 Speaker Recognition Evaluation dataset. We also obtained 4% absolute EER improvement for both-gender trials on the 10 s-10 s condition compared to the classical joint factor analysis scoring.
In this paper, we continue to analyze optimal dispatch of generation and transmission topology to meet load as a mixed integer program (MIP) with binary variables representing the state of the transmission element (line or transformer). Previous research showed a 25% savings by dispatching the IEEE 118-bus test case. This paper is an extension of that work. It presents how changing the topology affects nodal prices, load payment, generation revenues, cost, and rents, congestion rents, and flowgate prices. Results indicate that changing the topology to cut costs typically results in lower load payments and higher generation rents for this network. Computational issues are also discussed.
This study investigated the effect of antioxidants on lipid stability of frozen‐stored meat products. Buckwheat hull extract was used to enrich fried meatballs made from ground pork. During 180‐d storage of meat products, lipid oxidation (peroxide and 2‐thiobarbituric acid reactive substances [TBARS] value) was periodically monitored. The results were compared with butylated hydroxytoluene (BHT). The addition of antioxidants decreased lipid oxidation in stored meatballs. The highest ability to control peroxide and TBARS values was demonstrated for buckwheat hull extract. Moreover, buckwheat hull extract showed a higher 2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging activity as well as higher Fe(II) ion chelating ability, as compared with BHT. The total content of phenolic compounds are highly correlated to the individual polyphenols in extract of buckwheat hull, among which the following were assayed: 3,4‐dihydroxybenzoic acid, 4‐hydroxybenzoic acid, gallic acid, isovanillic acid and p ‐coumaric acid, and flavonoids: isoorientin, quercetin, quercetin 3‐ d ‐glucoside, rutin, and vitexin. These results indicate that plant extracts can be used to prolong shelf life of products by protecting them against lipid oxidation and deterioration of their nutritional quality. Nutritional and health aspects shed new light on the use of antioxidants in food technology. Polyphenolic compounds extracted from numerous plants have a high potential as materials for functional food development and production. Production of buckwheat groats generated by‐products, such as bran and hull, which apart from high content of dietary fiber, may also constitute valuable sources of antioxidants. They would form an ideal base for the design of a new generation of foods.
Globalization of the integrated circuit (IC) design industry is making it easy for rogue elements in the supply chain to pirate ICs, overbuild ICs, and insert hardware Trojans. Due to supply chain attacks, the IC industry is losing approximately 4 billion annually. One way to protect ICs from these attacks is to encrypt the design by inserting additional gates such that correct outputs are produced only when specific inputs are applied to these gates. The state-of-the-art logic encryption technique inserts gates randomly into the design, but does not necessarily ensure that wrong keys corrupt the outputs. Our technique ensures that wrong keys corrupt the outputs. We relate logic encryption to fault propagation analysis in IC testing and develop a fault analysis-based logic encryption technique. This technique enables a designer to controllably corrupt the outputs. Specifically, to maximize the ambiguity for an attacker, this technique targets 50% Hamming distance between the correct and wrong outputs (ideal case) when a wrong key is applied. Furthermore, this 50% Hamming distance target is achieved using a smaller number of additional gates when compared to random logic encryption.
Contents of total flavonoids, total phenolics, total triterpenes, total condensed tannin and total saponins in peels, flesh and endocarps of Chaenomeles speciosa (CSP) and Chaenomeles sinensis (CSS) were determined by colorimetric method, while 5 phenolics (vanillic, gallic, chlorogenic, ferulic and p ‐coumaric acids), 2 triterpenes (oleanolic and ursolic acids), and 3 flavonoids (rutin, catechin and epicatechin) were identified and quantified by high‐performance liquid chromatography‐mass spectrometry (HPLC‐MS) and HPLC, and antioxidant and α‐glucosidase inhibitory activities of them also were evaluated as well as their digestive characteristics. In the correlation analysis, total phenolics, vanillic acid, catechin, ursolic acid and oleanolic acid all contribute to DPPH · scavenge capacity, gallic acid contributes to total ferric reducing antioxidant power, while total triterpenes, total saponins, chlorogenic acid and ferullic acid contribute to α‐glucosidase inhibitory activity. In the principal component analysis, endocarps of CSP and CSS both show better quality than their peels and flesh, respectively. In vitro digestion can increase contents of total flavonoids, total condensed tannin and total saponins, while contents of total phenolics and total triterpenes decreased greatly. Our study would contribute to the full use of discarded parts of the 2 Chaenomeles and be helpful to establish a good foundation for further research of CSP and CSS.
This study investigated the compositional characteristics and shelf‐life of Njangsa seed oil (NSO). Oil from Njangsa had a high polyunsaturated fatty acid (PUFA) content of which alpha eleostearic acid (α‐ESA), an unusual conjugated linoleic acid was the most prevalent (about 52%). Linoleic acid was also present in appreciable amounts (approximately 34%). Our investigations also indicated that the acid‐catalyzed transesterification of NSO resulted in lower yields of α‐ESA methyl esters, due to isomerization, a phenomenon which was not observed under basic conditions. The triacylglycerol (TAG) profile analysis showed the presence of at least 1 α‐ESA fatty acid chain in more than 95% of the oil's TAGs. Shelf‐life was determined by the Weibull Hazard Sensory Method, where the end of shelf‐life was defined as the time at which 50% of panelists found the flavor of NSO to be unacceptable. This was determined as 21 wk. Our findings therefore support the potential commercial viability of NSO as an important source of physiologically beneficial PUFAs. Njangsa ( Ricinodendron heudelotii ) is a semi‐deciduous plant species indigenous to the coastal nations of West Africa. It contains a high percentage of heart‐healthy polyunsaturated fatty acids that could be used for health promoting applications. This study would benefit potential consumers due to the health promoting properties that result from the high concentration of conjugated linolenic acid in Njangsa oil. It will also benefit the communities in West Africa by commercializing the seed oil of a plant that is indigenous to their country.
The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of -[(4-(trifluoromethyl)phenyl]pyrazine-2-carboxamide have been investigated experimentally and theoretically using Gaussian09 software package. Potential energy distribution of normal modes of vibrations was done using GAR2PED program. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. From the NBO analysis it is evident that the increased electron density at the nitrogen and carbon atoms leads to the elongation of their respective bond lengths and a lowering of their corresponding stretching wavenumbers. The calculated geometrical parameters are in agreement with that of similar derivatives. The calculated first hyperpolarizability is high and the calculated data suggest an extended -electron delocalization over the pyrazine ring and carboxamide moiety which is responsible for the nonlinearity of the molecule.
Anti-islanding protection of distributed generators (DG) is a significant technical barrier to the emerging DG industry. This paper presents an innovative power line signaling based anti-islanding scheme developed in response to the challenge. The scheme broadcasts a signal from a substation to the DG sites using the distribution feeders as the signal paths. A DG is considered as islanded from the upstream system if the signal cannot be detected at the DG site. The proposed scheme has been evaluated using analytical, simulation and field tests. The results are very promising. This paper presents the main ideas of the scheme and its design considerations. Methods to create and detect the signals are shown and their performances are analyzed.
Quality management (QM) has received a high degree of attention in extant literature. Several research papers attribute superior firm performance to adoption of QM practices. The availability of a large number of research papers that investigate the impact of QM practices on performance provide an ideal setting for theory extension and refinement using meta-analysis techniques. In this paper a meta-analytic study is presented that fulfills two objectives. First, the paper formalizes performance implications of adopting QM practices and present hypothesized relationship between QM practices and performance. Second, a meta-analysis of correlation ( ) approach is used to examine the empirical research in QM to determine which QM practices are positively related to improved performance. The study also examines the presence of moderating factors in the association between QM practices and performance. The results support many hypothesized relationships and also point towards the presence of moderating factors in almost all QM practice–performance relationships. A discussion of the findings is presented and directions for further development of QM theory are proposed.
Automatic face recognition is now widely used in applications ranging from deduplication of identity to authentication of mobile payment. This popularity of face recognition has raised concerns about face spoof attacks (also known as biometric sensor presentation attacks), where a photo or video of an authorized person's face could be used to gain access to facilities or services. While a number of face spoof detection techniques have been proposed, their generalization ability has not been adequately addressed. We propose an efficient and rather robust face spoof detection algorithm based on image distortion analysis (IDA). Four different features (specular reflection, blurriness, chromatic moment, and color diversity) are extracted to form the IDA feature vector. An ensemble classifier, consisting of multiple SVM classifiers trained for different face spoof attacks (e.g., printed photo and replayed video), is used to distinguish between genuine (live) and spoof faces. The proposed approach is extended to multiframe face spoof detection in videos using a voting-based scheme. We also collect a face spoof database, MSU mobile face spoofing database (MSU MFSD), using two mobile devices (Google Nexus 5 and MacBook Air) with three types of spoof attacks (printed photo, replayed video with iPhone 5S, and replayed video with iPad Air). Experimental results on two public-domain face spoof databases (Idiap REPLAY-ATTACK and CASIA FASD), and the MSU MFSD database show that the proposed approach outperforms the state-of-the-art methods in spoof detection. Our results also highlight the difficulty in separating genuine and spoof faces, especially in cross-database and cross-device scenarios.