Globalization and stock market returns

Global Economy Journal61

Flexural behaviour of hybrid FRP-concrete-steel double skin tubular members

This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the steel tube and the FRP tube, respectively. The results presented in this paper show that these hybrid beams have a very ductile response because the compressive concrete is confined by the FRP tube and the steel tube provides ductile longitudinal reinforcement. The beams\u27 flexural response, including the flexural stiffness, ultimate load, and cracking, can be substantially improved by shifting the inner steel tube toward the tension zone or by providing FRP bars as additional longitudinal reinforcement. The predictions from the theoretical model are in reasonably close agreement with the test results. Differences between the test and predicted results arise from factors not considered in the theoretical model, including the existence of a strain gradient in the confined concrete, concentrations of cracks and the slips between the concrete and the two tubes; these are issues to be accounted for in the development of a more accurate model in the future

Steam System Optimization at Palm Oil Mill: Case Study in Sabah, Malaysia

In this paper, a preliminary study of industrial steam system reveals that most of the industrial steam user especially the palm oil mill did not bother to save energy as long as the mill meets their productions target and is getting profits for the company. The management is not aware that a huge amount of energy is being wasted during the processes of extracting oil from the fresh fruit bunch (FFB). To embark this study, Steam System Scoping Tool (SSST), Steam System Assessment Tool (SSAT) and 3E Plus: Insulation Program Software, provided by the United Nations Industrial Development Organization (UNIDO) are used to assess the efficiency of steam system operations. The tools also assist in preliminary assessments of how efficiently the steam system is operating. After analyses are conducted, the proposed improvement project is recommended to modify the system back to its initial designed best efficiency. The results also show that there were various losses that are contributing to the energy waste and its cost impact to the mill. Meanwhile, the boiler efficiency was only about 68.6%. The findings proposed steam system optimization (SSO) opportunities by installing the feedwater economizer and reducing the blowdown rate of the boiler. The efficiency of the boiler was increased to 77% from its current operating condition. This also improved the steam quality and production output of the mill. Through these SSO, the annual demand saving is around 4.9 MW, with an energy saving of 75,276 GJ/yr., capable of reducing 13,002 metric tons of carbon dioxide emissions per annum and save 598.3 Tph/yr of biomass fuel. Thus, through this steam system optimization the estimated annual net cost savings are around USD 100,000.00. This paper aims at promoting similar system optimization projects at other plants throughout Malaysia, as it benefits to all industrial steam user especially the palm oil mill industries in Malaysia

Applications of patching to quadratic forms and central simple algebras

This paper provides applications of patching to quadratic forms and central simple algebras over function fields of curves over henselian valued fields. In particular, we use a patching approach to reprove and generalize a recent result of Parimala and Suresh on the u-invariant of p-adic function fields, for p odd. The strategy relies on a local-global principle for homogeneous spaces for rational algebraic groups, combined with local computations.Comment: 48 pages; connectivity now required in the definition of rational group; beginning of Section 4 reorganized; other minor change

Low-field magnetoresistance in GaAs 2D holes

We report low-field magnetotransport data in two-dimensional hole systems in GaAs/AlGaAs heterostructures and quantum wells, in a large density range, $2.5 \times 10^{10} \leq p \leq 4.0 \times 10^{11}$ cm$^{-2}$, with primary focus on samples grown on (311)A GaAs substrates. At high densities, $p \gtrsim 1 \times 10^{11}$ cm$^{-2}$, we observe a remarkably strong positive magnetoresistance. It appears in samples with an anisotropic in-plane mobility and predominantly along the low-mobility direction, and is strongly dependent on the perpendicular electric field and the resulting spin-orbit interaction induced spin-subband population difference. A careful examination of the data reveals that the magnetoresistance must result from a combination of factors including the presence of two spin-subbands, a corrugated quantum well interface which leads to the mobility anisotropy, and possibly weak anti-localization. None of these factors can alone account for the observed positive magnetoresistance. We also present the evolution of the data with density: the magnitude of the positive magnetoresistance decreases with decreasing density until, at the lowest density studied ($p = 2.5 \times 10^{10}$ cm$^{-2}$), it vanishes and is replaced by a weak negative magnetoresistance.Comment: 8 pages, 8 figure

Influence of pyrolysis temperature on the characteristics and lead(II) adsorption capacity of phosphorus-engineered poplar sawdust biochar

Phosphorus (P)–engineered biochars (BCP) were prepared via co-pyrolysis of poplar sawdust and monopotassium phosphate (KH2PO4) (10 %, w/w) at 300 ℃, 500 ℃ and 700 ℃ to evaluate their potential lead [Pb(II)] adsorption. Effects of pH, contact time, and initial Pb(II) concentration on the Pb(II) adsorption capacity of the biochars were investigated. The physico-chemical, morphological, porous structure, crystallinity and spectroscopic characteristics of pre- and post-Pb-adsorbed biochars were analyzed to unravel the Pb(II) adsorption mechanism. Results showed that KH2PO4 reacted with biomass carbon to form stable C–P and/or C–O–P groups in BCP, and increased carbon retention and aromaticity of BCP. However, the addition of KH2PO4 led to an adverse effect on porous structure, e.g. surface area of biochars produced at 300 ℃, 500 ℃ and 700 ℃ were decreased by 41.53 %, 80.32 %, and 59.74 %, respectively. Adsorption experiments displayed that BCP produced at 300 ℃ exhibited the highest Pb(II) adsorption capacity (qmax = 154.7 mg g−1), which was almost 6 times higher than the pristine biochar (qmax = 24.3 mg g−1). Potassium polymetaphosphate [(KPO3)n] particles were attached on the surface of BCP, which facilitated the precipitation of Pb(II) to form [Pb(PO3)2]n, Pb5(PO4)3OH and PbHPO4. This study thus demonstrated the effect of pyrolysis temperature on the enhancing removal capability of P-modified biochar for Pb(II) from aqueous solutions

Automatic service categorisation through machine learning in emergent middleware

The modern environment of mobile, pervasive, evolving services presents a great challenge to traditional solutions for enabling interoperability. Automated solutions appear to be the only way to achieve interoperability with the needed level of flexibility and scalability. While necessary, the techniques used to determine compatibility, as a precursor to interaction, come at a substantial computational cost, especially when checks are performed between systems in unrelated domains. To overcome this, we apply machine learning to extract high-level functionality information through text categorisation of a system's interface description. This categorisation allows us to restrict the scope of compatibility checks, giving an overall performance gain when conducting matchmaking between systems. We have evaluated our approach on a corpus of web service descriptions, where even with moderate categorisation accuracy, a substantial performance benefit can be found. This in turn improves the applicability of our overall approach for achieving interoperability in the Connect project