A Numerical Study of Improved Quark Actions on Anisotropic Lattices

Tadpole improved Wilson quark actions with clover terms on anisotropic lattices are studied numerically. Using asymmetric lattice volumes, the pseudo-scalar meson dispersion relations are measured for 8 lowest lattice momentum modes with quark mass values ranging from the strange to the charm quark with various values of the gauge coupling $\beta$ and 3 different values of the bare speed of light parameter $\nu$. These results can be utilized to extrapolate or interpolate to obtain the optimal value for the bare speed of light parameter $\nu_{opt}(m)$ at a given gauge coupling for all bare quark mass values $m$. In particular, the optimal values of $\nu$ at the physical strange and charm quark mass are given for various gauge couplings. The lattice action with these optimized parameters can then be used to study physical properties of hadrons involving either light or heavy quarks.Comment: 22 pages, 7 figures, 2 tables. Analysis greatly modified compared with previous versio

Building of small bamboo shelter : basic material properties

With the rapid increase in population in developing countries around the world, concerns about housing problems have been on the rise as many lose their homes as a result of such disasters. As such, it is crucial to build housing with materials that are self-substantial and environmentally friendly. Bamboo, which has a favorable mechanical property is an ideal material to be used to build houses to enable the local community to create proper housing in a sustainable manner. The context of this project aims to conduct a series of tests to have a better understanding on the material properties of bamboo and for the construction of the small bamboo shelter for the needy people. In collaboration with Lien Institute for Environment (LIFE), this project aims to address the issues of people accessing to stable and safe accommodation. Experimental testing that was done for this project included the tensile test, bending test, buckling test, compression test and bearing test. As part of the dual project, this report will be focusing on the buckling, compression and bearing strength of the bamboo. A literature review about bamboo as a structural element and buckling, compression and bearing test has been documented too. In addition, a methodology, observations made and data analysis will be discussed as well. A copy of this report will be submitted to Lien Institute for the Environment (LIFE) of School of Civil and Environmental Engineering. The report can be served as a guideline for future projects and research done in this particular area of study.Bachelor of Engineering (Civil

A Numerical and Experimental Study of Marine Hydrogen–Natural Gas–Diesel Tri–Fuel Engines

Maritime shipping is a key component of the global economy, representing 80–90% of international trade. To deal with the energy crisis and marine environmental pollution, hydrogen-natural gas-diesel tri-fuel engines have become an attractive option for use in the maritime industry. In this study, numerical simulations and experimental tests were used to evaluate the effects of different hydrogen ratios on the combustion and emissions from these engines. The results show that, in terms of combustion performance, as the hydrogen proportion increases, the combustion ignition delay time in the cylinder decreases and the laminar flame speed increases. The pressure and temperature in the cylinder increase and the temperature field distribution expands more rapidly with a higher hydrogen ratio. This means that the tri-fuel engine (H2+CH4+Diesel) has a faster response and better power performance than the dual-fuel engine (CH4+Diesel). In terms of emission performance, as the hydrogen proportion increases, the NO emissions increase, and CO and CO2 emissions decrease. If factors such as methane escape into the atmosphere from the engine are considered, the contribution of marine tri-fuel engines to reducing ship exhaust emissions will be even more significant. Therefore, this study shows that marine hydrogen-natural gas-diesel tri-fuel engines have significant application and research prospects

Application of Aegilops tauschii–Triticum aestivum recombinant inbred lines for grain protein content quantitative trait loci detection and wheat improvement

Grain protein content (GPC) is an important nutritional quality trait of wheat. Aegilops tauschii Coss. is a progenitor of common wheat and has been shown to have high GPC. The objective of this study was to identify quantitative trait loci (QTL) for GPC using A. tauschii–Triticum aestivum L. recombinant lines. An advanced BC2F6 population (112 lines) containing A. tauschii segments was developed using synthetic octaploid wheat (hexaploid wheat Zhoumai 18 × A. tauschii T093), which displayed significant phenotype variances. Two quality traits, GPC and wet gluten, and four yield-related traits, thousand kernel weight, spikelet number per plant, grain number per spike, and grain weight per spike, were evaluated. The results show that the mean GPCs of these lines were significantly higher than those of Zhoumai 18. Correlation and mapping analyses indicated that quality traits were weakly negatively correlated with yield traits. Furthermore, 16 A. tauschii-derived QTL for GPC were detected in the recombinant inbred lines, and four stable QTL that have no significant negative effects on yield and are located within the same marker interval were detected in both environments. Additionally, high-protein, high-yield lines 150228 and 150368 with stable QTL were obtained, and both can be directly utilised for fine mapping of the GPC genes and molecular marker–assisted selection to achieve synergistic improvement of wheat yield and protein content.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

A Numerical and Experimental Study of Marine Hydrogen–Natural Gas–Diesel Tri–Fuel Engines

Maritime shipping is a key component of the global economy, representing 80–90% of international trade. To deal with the energy crisis and marine environmental pollution, hydrogen-natural gas-diesel tri-fuel engines have become an attractive option for use in the maritime industry. In this study, numerical simulations and experimental tests were used to evaluate the effects of different hydrogen ratios on the combustion and emissions from these engines. The results show that, in terms of combustion performance, as the hydrogen proportion increases, the combustion ignition delay time in the cylinder decreases and the laminar flame speed increases. The pressure and temperature in the cylinder increase and the temperature field distribution expands more rapidly with a higher hydrogen ratio. This means that the tri-fuel engine (H2 +CH4 +Diesel) has a faster response and better power performance than the dual-fuel engine (CH4 +Diesel). In terms of emission performance, as the hydrogen proportion increases, the NO emissions increase, and CO and CO2 emissions decrease. If factors such as methane escape into the atmosphere from the engine are considered, the contribution of marine tri-fuel engines to reducing ship exhaust emissions will be even more significant. Therefore, this study shows that marine hydrogen-natural gas-diesel tri-fuel engines have significant application and research prospects

A numerical and experimental study of marine hydrogen–natural gas–diesel tri–fuel engines

Maritime shipping is a key component of the global economy, representing 80–90% of international trade. To deal with the energy crisis and marine environmental pollution, hydrogen-natural gas-diesel tri-fuel engines have become an attractive option for use in the maritime industry. In this study, numerical simulations and experimental tests were used to evaluate the effects of different hydrogen ratios on the combustion and emissions from these engines. The results show that, in terms of combustion performance, as the hydrogen proportion increases, the combustion ignition delay time in the cylinder decreases and the laminar flame speed increases. The pressure and temperature in the cylinder increase and the temperature field distribution expands more rapidly with a higher hydrogen ratio. This means that the tri-fuel engine (H2 +CH4 +Diesel) has a faster response and better power performance than the dual-fuel engine (CH4 +Diesel). In terms of emission performance, as the hydrogen proportion increases, the NO emissions increase, and CO and CO2 emissions decrease. If factors such as methane escape into the atmosphere from the engine are considered, the contribution of marine tri-fuel engines to reducing ship exhaust emissions will be even more significant. Therefore, this study shows that marine hydrogen-natural gas-diesel tri-fuel engines have significant application and research prospects