Discriminative Tandem Features for HMM-based EEG Classification

Abstract—We investigate the use of discriminative feature extractors in tandem configuration with generative EEG classification system. Existing studies on dynamic EEG classification typically use hidden Markov models (HMMs) which lack discriminative capability. In this paper, a linear and a non-linear classifier are discriminatively trained to produce complementary input features to the conventional HMM system. Two sets of tandem features are derived from linear discriminant analysis (LDA) projection output and multilayer perceptron (MLP) class-posterior probability, before appended to the standard autoregressive (AR) features. Evaluation on a two-class motor-imagery classification task shows that both the proposed tandem features yield consistent gains over the AR baseline, resulting in significant relative improvement of 6.2% and 11.2 % for the LDA and MLP features respectively. We also explore portability of these features across different subjects. Index Terms- Artificial neural network-hidden Markov models, EEG classification, brain-computer-interface (BCI)

Cross match-CHMM fusion for speaker adaptation of voice biometric

The most significant factor affecting automatic voice biometric performance is the variation in the signal characteristics, due to speaker-based variability, conversation-based variability and technology variability. These variations give great challenge in accurately modeling and verifying a speaker. To solve this variability effects, the cross match (CM) technique is proposed to provide a speaker model that can adapt to variability over periods of time. Using limited amount of enrollment utterances, a client barcode is generated and can be updated by cross matching the client barcode with new data. Furthermore, CM adds the dimension of multimodality at the fusion-level when the similarity score from CM can be fused with the score from the default speaker modeling. The scores need to be normalized before the fusion takes place. By fusing the CM with continuous Hidden Markov Model (CHMM), the new adapted model gave significant improvement in identification and verification task, where the equal error rate (EER) decreased from 6.51% to 1.23% in speaker identification and from 5.87% to 1.04% in speaker verification. EER also decreased over time (across five sessions) when the CM is applied. The best combination of normalization and fusion technique methods is piecewise-linear method and weighted sum

Gray-level co-occurrence matrix bone fracture detection

Problem statement: Currently doctors in orthopedic wards inspect the bone x-ray images according to their experience and knowledge in bone fracture analysis. Manual examination of x-rays has multitude drawbacks. The process is time-consuming and subjective. Approach: Since detection of fractures is an important orthopedics and radiologic problem and therefore a Computer Aided Detection(CAD) system should be developed to improve the scenario. In this study, a fracture detection CAD based on GLCM recognition could improve the current manual inspection of x-ray images system. The GLCM for fracture and non-fracture bone is computed and analysis is made. Features of Homogeneity, contrast, energy, correlation are calculated to classify the fractured bone. Results: 30 images of femur fractures have been tested, the result shows that the CAD system can differentiate the x-ray bone into fractured and nonfractured femur. The accuracy obtained from the system is 86.67. Conclusion: The CAD system is proved to be effective in classifying the digital radiograph of bone fracture. However the accuracy rate is not perfect, the performance of this system can be further improved using multiple features of GLCM and future works can be done on classifying the bone into different degree of fracture specifically

Optimization of Post-Annealing Treatment Conditions on GaN Layer Grown on m-Plane Sapphire Substrate by Electron Beam Evaporator

This paper describes the effect of using different conditions of post-annealing treatment on properties of GaN layer grown on m-plane sapphire by electron beam (e-beam) evaporator. Prior to the annealing, the surface of the grown GaN was found to be smooth with some agglomerations of its grains in a specific direction on the surface. A weak signature of GaN (100) together with Ga203 crystals were also detected. When the annealing was demonstrated at 650°C in N2 ambient, the evidence of Ga203 disappears, especially at 30 minutes of annealing. Annealing in NHa ambient at the same temperature eliminated the GaN (100) crystals but the existence of Ga203 was expected. Further annealing at 950°C in ammonia (NHa) ambient has successfully produced a better non-polar GaN in (100) direction. However, inclusions of GaN (002) and (101) crystals were also detected. Increase in annealing temperature at 980°C and 1100°C caused deteriorations of the structural and optical properties of the GaN layer. From this work, we proposed that the properties of GaN crystalline structure can be controlled by varying the conditions of the post-annealing treatment

Factors associated with low birthweight in term pregnancies: A matched case-control study from rural Pakistan

Low birthweight (LBW) remains a significant public health problem in Pakistan and further understanding of factors associated with LBW is required. We conducted a hospital-based matched case control study to identify risk factors associated with LBW in a rural district of Pakistan. We found that illiteracy (AOR: 2.68; 95% CI: 1.59 - 4.38), nulliparity (AOR: 1.82; 95% CI: 1.26-2.44), having a previous miscarriage/abortion (AOR: 1.22; 95% CI: 1.06-2.35), having \u3c 2 antenatal care (ANC) visits during last pregnancy (AOR: 2.43; 95% CI: 1.34-2.88), seeking ANC in third trimester (AOR: 3.62; 95% CI : 2.14-5.03), non-use of iron folic acid during last pregnancy (AOR: 2.72; 95% CI: 1.75-3.17), having hypertension during last pregnancy (AOR: 1.42; 95% CI: 1.13-2.20), being anemic (AOR: 2.67; 95% CI: 1.65-5.24) and having postpartum weight o

Enhancing tool life of hot isostatically pressed silicon nitride inserts in machining inconel 718 with different susceptors through hybrid microwave post sintering

Hybrid Microwave sintering has become a growing interest for heating and synthesizing ceramic materials due to its capabilities in successfully enhancing densification and improving mechanical and structural properties. Silicon Nitride (Si3N4) based cutting inserts have outstanding properties for machining hard materials such as cast iron, hard steel and nickel based super alloys. This research aims to analyze the effect of different susceptors on the tool life of various Si3N4 inserts (90Si3N4 4Y2O3 2.5MgO 2Al2O3 1.5SiO) that have been synthesized in machining Inconel 718. The Si3N4 inserts have been synthesized by means of Hot Isostatic Pressing (HIP) at 1800°C and followed by Hybrid Microwave (HMW) post-sintering at 200°C for 10 minutes with the aid of three different susceptors; Silicon Carbide (SiC), Graphite (G) and mixture of (SiC + G) powders. Density, hardness, micro structural properties and tool wear were analyzed. HMW post sintering for only 10 minutes using SiC, G and SiC+G susceptors enhanced the density (97-98%TD) and hardness (27-58%) significantly. Finer uniform grains and less porosities were produced particularly for Si3N4 inserts produced by HMW (SiC+G) when compared with HMW (SiC) and HMW (G). Tool life for the Si3N4 inserts were improved by 10-17% HMW(SiC), 20-53 % HMW(G) and 32-88% HMW(SiC+G) for the cutting speeds of 100, 125 and 160 m/min. Hence, the mixture of SiC +G powders as susceptors produced the best outcome for Si3N4 inserts with enhanced densification, hardness, wear resistance, and longer tool life (88% increment at 100 m/min) when compared with the commercial tool (RNGN 6060) in machining Inconel 718

Enzymatic hydrolysis of palm olein with mycelium-bound lipase of Aspergillus flavus Link (Hydrolysis minyak olein menggunakan lipase terikat miselium daripada Aspergillus flavus Link)

Abstrak Hidrolisis minyak olein menggunakan lipase-terikat miselium daripada Aspergillus flavus Link telah dikaji. Komposisi asid lemak, profil triasigliserol dan sifat lebur minyak olein sebelum dan selepas 72 jam tindak balas dibandingkan. Kepekatan asid palmitik didapati menurun sedikit diikuti dengan pertambahan asid oleik dan asid linolenik pada minyak tersebut. Kepekatan bandingan bagi triasigliserol tri-tak tepu, minyak olein terubahsuai yang mempunyai takat lebur rendah, seperti trioleoil gliserol, oleoil-dilinoleiol gliserol dan dioleoil oleoil gliserol, didapati meningkat, manakala kepekatan triasigliserol yang mempunyai takat lebur tinggi seperti dipalmitoil-oleoil gliserol dan palmitoil-oleoil steroil gliserol berkurangan kecuali tripalmitoil gliserol. Julat lebur bagi minyak olein terubah suai selepas tindak balas didapati menjadi lebar, iaitu apabila minyak mula lebur (X 1 ) pada suhu -28 °C dan lebur keseluruhannya (X 2 ) pada suhu 45 °C. Abstract Hydrolysis of palm olein was studied using mycelium-bound lipase of Aspergillus flavus Link. The fatty acid composition, triacylglycerol profile and melting properties of the palm olein before and after 72 h hydrolysis were compared. A slight decrease of palmitic acid and increase in oleic acid and linolenic acid concentrations in palm olein was noted. The relative concentration of triunsaturated triacylglycerol, low melting glycerides, such as trioleoyl glycerol, oleoyl-dilinoleoyl glycerol and dioleoyl-linoleoyl glycerol of modified palm olein was increased while the relative concentration of high melting glycerides e.g. dipalmitoyl-oleoyl glycerol and palmitoyl-oleoyl-steroyl glycerol was decreased except for tripalmitoyl glycerol. The melting range of modified palm olein tends to be broad, that is it starts melting (X 1 ) at -28 °C and totally melted (X 2 ) at 45 °C

Geospatial analysis of urban land use pattern analysis for haemorrhagic fever risk: a review

Human modification of the natural environment continues to create habitats in which vectors of a wide variety of human and animal pathogens (such as Plasmodium, Aedes aegypti, Arenavirus etc.) thrive if unabated with an enormous potential to negatively affect public health. Typical examples of these modifications include impoundments, dams, irrigation systems, landfills and so on that provide enabled environment for the transmission of Hemorrhagic fever such as malaria, dengue, avian flu, Lassa fever etc. Furthermore, contemporary urban dwelling pattern appears to be associated with the prevalence of Hemorrhagic diseases in recent years. These observations are not peculiar to the developing world, as urban expansion also contributes significantly to mosquito and other vectors habitats. This habitats offer breeding ground to some vector virus populations. The key to disease control is developing an understanding of the contribution of human landscape modification to vector-borne pathogen transmission and how a balance may be achieved between human development, public health, and responsible urban land use. A comprehensive review of urban land use Pattern Analysis for Hemorrhagic fever risk has been conducted in this paper. The study found that most of the available literatures dwell more on the impact of urban land use on malaria and dengue fevers; however, studies are yet to be found discussing the implications of urban land use on the risk of Ebola, Lassa and other non-mosquito borne VHFs. A relational model for investigating the influence of urban land use change pattern on the risk of Hemorrhagic fever has been proposed in this study

Exchangeable zinc pool size at birth in Pakistani small for gestational age and appropriate for gestational age infants do not differ but are lower than in US infants

Objectives: Small for gestational age (SGA) infants are more susceptible to infectious morbidity and growth faltering compared to their appropriate for gestational age (AGA) counterparts. Zinc supplementation of SGA infants may be beneficial but the underlying susceptibility to zinc deficiency of SGA infants has not been examined.Methods: In a community-based, observational, longitudinal study in a peri-urban settlement of Karachi, Pakistan, we compared the size of the exchangeable zinc pools (EZPs) in term SGA and AGA infants at birth and at 6 months of age, hypothesizing that the EZP would be lower in the SGA group. To measure EZP size, a zinc stable isotope was intravenously administered within 48 hours of birth (n = 17 and 22) at 6 months (n = 11 and 14) in SGA and AGA infants, respectively. Isotopic enrichment in urine was used to determine EZP.Results: No significant difference was detected in the mean (±standard deviation) EZP between SGA and AGA infants at birth, with values of 9.8 ± 3.5 and 10.1 ± 4.1 mg/kg, respectively (P = 0.86), or at 6 months. Longitudinal EZP measurements demonstrated a significant decline in EZP relative to body weight in both groups at 6 months (P \u3c 0.001). Mean EZP (adjusted for body weight) size at birth for the combined Pakistani groups was significantly lower than AGA infants at birth in the United States (P = 0.017).Conclusions: These results did not support a difference in zinc endowment between SGA and AGA Pakistani infants. They, however, do suggest lower in utero zinc transfer to the fetus in a setting where poor maternal nutritional status may confer a high susceptibility to postnatal zinc deficiency

3D MODELING FOR ROCK ART DOCUMENTATION USING LIGHTWEIGHT MULTISPECTRAL CAMERA

This paper discusses the use of the lightweight multispectral camera to acquire three-dimensional data for rock art documentation application. The camera consists of five discrete bands, used for taking the motifs of the rock art paintings on a big structure of a cave based on the close-range photogrammetry technique. The captured images then processed using commercial structure-from-motion photogrammetry software, which automatically extracts the tie point. The extracted tie points were then used as input to generate a dense point cloud based on the multi-view stereo (MVS) and produced the multispectral 3D model, and orthophotos in a different wavelength. For comparison, the paintings and the wall surface also observed by using terrestrial laser scanner which capable of recording thousands of points in a short period of time with high accuracy. The cloud-to-cloud comparison between multispectral and TLS 3D point cloud show a sub-cm discrepancy, considering the used of the natural features as control target during 3D construction. Nevertheless, the processing also provides photorealistic orthophoto, indicates the advantages of the multispectral camera in generating dense 3D point cloud as TLS, photorealistic 3D model as RGB optic camera, and also with the multiwavelength output