Corrosion study of pipeline material for seabed sediment in tropical climate

Corrosive environments such as marine sediments can cause corrosion to steel pipelines at any time when certain conditions are met. Seabed sediment could cause severe corrosion damage due to its corrosiveness to the pipelines buried under it. Many consequences could take place in case if there is incident in oil/gas pipelines. Successfully identifying elements of corrosion in marine sediment would enhance the future of steel structure protection and monitoring systems. This article focuses on the behaviour of corrosion rate of steel located near shore environment and the aim is to determine the effect of sediment on corrosion of steel. To investigate that, simulated near shore sediment conditions have been used where the steel coupons buried in sediments which have different characteristics. Weight loss technique has been implemented to determine the weight loss rate of the steel specimens. Based on the results of this study, metal weight loss increases as the duration of exposure to seabed sediment environment become longer. The sea sediment simulated condition has given significant levels of corrosion. Conclusively, the corrosion rate of steel in seabed sediment located in tropical region is complicated and further studies are suggested

Failure Analysis and Mechanisms of Failure of Fibrous Composite Structures

The state of the art of failure analysis and current design practices, especially as applied to the use of fibrous composite materials in aircraft structures is discussed. Deficiencies in these technologies are identified, as are directions for future research

Biodegradation of dodecylbenzene solfonate sodium by Stenotrophomonas maltophilia Biofilm

Immobilization for microbial cultures has proved to be advantageous in municipal and industrial sewage treatment because of high degradation efficiency and good operational stability. In this survey, a bacterial strain was isolated from activated sludge that utilized branched anionic surfactants (BAS) as a sole carbon source. Identification of isolated strain was from 16S rRNA sequencing method. The immobilized cells on silanized glass beads as support and unmodified surfaces were used for removal of BAS; both types showed effective biodegrading of BAS. The removal rate in silanized surface was about 2 fold of unmodified surface. The result of biodegradation was studied by HPLC method and scanning electron microscope

The impact of Sharia compliance on the adjustment to target debt maturity of Malaysian firms

This paper investigates the speed of adjustment to target debt maturity for a sample of Malaysian firms based on the sample period of 2007 to 2016. We examine the impact of Sharia compliance on the speed of adjustment to target debt maturity structure by grouping companies based on nature of compliance to Sharia requirements which is categorised by the Securities Commission of Malaysia. In line with our expectations, the analysis shows that firms classified as Sharia compliant tend to adjust at more rapid rates to target debt maturity when below target levels suggesting that compliant firms are able to issue long-term debt at cheaper levels relative to non-compliant counterparts. In addition, the reverse is observed when evaluating firms above target levels where non-compliant firms adjust at more rapid rates. Our findings indicate that compliant firms are able to raise long-term debt at cheaper rates relative to non-compliant firms given the captive market situation observed in the Islamic capital markets in Malaysia. This does however indicate the potential for higher agency costs as well as greater levels of information asymmetry for compliant firms relative to non-compliant firms given that non-compliant firms are more willing to reduce maturity structures to reach target levels when above target levels.peer-reviewe

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