CFD methodology development for Singapore Green Mark Building application

In the recent decade, investigation on the total building performance has become increasingly important for the environmental modelling community. With the advance of integrated design and modelling tool and Building Information Modelling (BIM) development, it is now possible to simulate and predict the building energy efficiency, air quality & health assessment, risk analysis & mitigation scenario for our urban planning analysis; all seamlessly in a single urban digital platform. In order to achieve the national goal of at least 80% of the buildings in Singapore to be green by 2030, Singapore Government has introduced the new BCA Green Mark 2015 scheme for accelerating the green building agenda. During the recent third Green Building Masterplan announced in 2015, it was decided to engage building tenants and occupants more actively to drive energy consumption behavioural change and to address the well-being of the people. Following up from this Masterplan, it is important for both the stakeholders and agency to jointly develop Performance Driven and Scientific Based Simulation Methodology and Evaluation Parameters as a frame work to evaluate the building design based on Singapore's hot and humid climate and densely-built-up urban areas for the Green Mark 2015 Scheme. In this paper, we will present the methodology and perform a baseline case study for the natural ventilation performance with the typical Non-Residential Building (NRB) industrial building. This can be resulted in the comprehensive CFD Quality Check List for the Environmental Sustainable Design (ESD) consultant in order to maintain modelling result accuracy. Demonstration on Indoor Air Quality (IAQ) using Air Exchange Effectiveness (AEE) as performance indicator will also be illustrated

Farm price prediction using case-based reasoning approach-A case of broiler industry in Taiwan

Since Taiwan joined the World Trade Organization (WTO) in 2002, pricing decision has become more essential to the development of the broiler industry. The effective prediction of broiler prices is essential from the viewpoint of the agriculture authority and the Poultry Association, thus a more realistic broiler price structure can assist the government to manage the national production resources more effectively. This research proposes a weighted case-based reasoning (CBR) approach to construct a price prediction model. The genetic algorithm model was adopted to find out the most suitable feature weights for CBR. Previous local production data and economic indices, along with information about imported chicken, were collected to build the prediction model. The experimental results indicated that the proposed CBR approach could exhibit a better prediction performance than the ones exhibited by linear regression, regression tree, and neural nets approaches. The findings also revealed that broiler prices were mostly influenced by the prices of colorful broilers and chicks. (C) 2009 Elsevier B.V. All rights reserved

Price information evaluation and prediction for broiler using adapted case-based reasoning approach

Predicting the upcoming broiler market price is important for the producers in developing their production plan. Effective price prediction model can aid producers to prevent over production or production shortage of broilers in advance. This research proposes all adapted CBR approach for predicting broiler price. The results indicate that the proposed adapted CBR approach demonstrates superior prediction performance than tin-adapted CBR approach, CART. artificial neural nets and linear regression with at least 50% less of mean average error. This study finds that adjusting the price of the most similar case by considering the similarity distance to the case being predicted is a key to improve the prediction accuracy of the case-based broiler price estimation model. (C) 2007 Elsevier Ltd. All rights reserved

Structural- and optical-properties analysis of single crystalline hematite (α-Fe2O3) nanocubes prepared by one-pot hydrothermal approach

High quality single crystal hematite (α-Fe2O3) nanocubes with average dimensions of 40 nm were successfully synthesized by a facile one-pot hydrothermal method. Systematic analyses were performed to investigate the morphological-, structural- and optical-properties of the as-synthesized α-Fe2O3 nanocubes. Continuous formation and hourly monitoring towards proper arrangement of single crystal α-Fe2O3 nanocubes was observed throughout the hydrothermal heating process of 180 °C from 4 h to 12 h. The probable growth mechanism on the formation of cubic nanostructures is also proposed. Electron micrographs show the cubic α-Fe2O3 synthesized at the most optimum 8 h hydrothermal heating duration are indeed produced in high-yield with a well-defined cubical shape. The typical rhombohedral structure of cubic α-Fe2O3 was evident from the XRD pattern. The SAED pattern indicates that the α-Fe2O3 nanocubes are single-crystalline in nature, with lattice-fringes and a d-spacing value of 3.6 Å. The optical characterization reveals that α-Fe2O3 nanocubes show strong visible-light absorption with a band gap energy of ∼2.1 eV while the photoluminescence emission spectra depicts a mono-peak centered at ∼590 nm. Both the SAED pattern and UV-vis spectra show a strong correlation with the standard α-Fe2O3. The as-synthesized α-Fe2O3 single crystal is of high quality that potentially could be used as a visible-light active nanomaterial in renewable energy device applications

Temperature-Driven Structural and Morphological Evolution of Zinc Oxide Nano-Coalesced Microstructures and Its Defect-Related Photoluminescence Properties

In this paper, we address the synthesis of nano-coalesced microstructured zinc oxide thin films via a simple thermal evaporation process. The role of synthesis temperature on the structural, morphological, and optical properties of the prepared zinc oxide samples was deeply investigated. The obtained photoluminescence and X-ray photoelectron spectroscopy outcomes will be used to discuss the surface structure defects of the prepared samples. The results indicated that the prepared samples are polycrystalline in nature, and the sample prepared at 700 °C revealed a tremendously c-axis oriented zinc oxide. The temperature-driven morphological evolution of the zinc oxide nano-coalesced microstructures was perceived, resulting in transformation of quasi-mountain chain-like to pyramidal textured zinc oxide with increasing the synthesis temperature. The results also impart that the sample prepared at 500 °C shows a higher percentage of the zinc interstitial and oxygen vacancies. Furthermore, the intensity of the photoluminescence emission in the ultraviolet region was enhanced as the heating temperature increased from 500 °C to 700 °C. Lastly, the growth mechanism of the zinc oxide nano-coalesced microstructures is discussed according to the reaction conditions

SnO2 Nanoparticles Decorated 2D Wavy Hierarchical Carbon Nanowalls with Enhanced Photoelectrochemical Performance

Two-dimensional carbon nanowall (2D-CNW) structures were prepared by hot wire assisted plasma enhanced chemical vapor deposition (hw-PECVD) system on silicon substrates. Controlled variations in the film structure were observed with increase in applied rf power during deposition which has been established to increase the rate of dissociation of precursor gases. The structural changes resulted in the formation of wavy-like features on the 2D-CNW, thus further enhancing the surface area of the nanostructures. The FESEM results confirmed the morphology transformation and conclusively showed the evolution of the 2D-CNW novel structures while Raman results revealed increase in ID/IG ratio indicating increase in the presence of disordered domains due to the presence of open edges on the 2D-CNW structures. Subsequently, the best 2D-CNW based on the morphology and structural properties was functionalized with tin oxide (SnO2) nanoparticles and used as a working electrode in a photoelectrochemical (PEC) measurement system. Intriguingly, the SnO2 functionalized 2D-CNW showed enhancement in both Mott-Schottky profiles and LSV properties which suggested that these hierarchical networks showed promising potential application as effective charge-trapping medium in PEC systems

ZnO nanonails: Organometallic synthesis, self-assembly and enhanced hydrogen gas production

We report the rational synthesis and characterizations of defect-rich zinc oxide (ZnO) nanonails that were prepared by organometallic approach and their implementation as an efficient photocatalyst for hydrogen (H2) generation. The ZnO nanonails were prepared from zinc stearate in n-octadecene that serves as non-coordinating solvent without the presence of any capping agent. Transmission electron microscopy (TEM) studies reveal that the individual triangular prismatic nanonail has an average edge length of 50–70 nm and it appears to have preferred growth orientation along [0001] crystal axis. Intriguingly, this nanonails show oriented-attachment along the flat-basal edge and self-assembled into twinned structure. Such structure is interconnected via a narrow-gap to form symmetrical twinned-like nanonails with truncated tips at both ends. In comparison to ZnO commercial nanopowder, ZnO nanonails show significant enhancement in photocatalytic H2 gas generation rate of 53.33% under UV light for 5 h. These results demonstrate ZnO nanonails to be a substantial potential photocatalyst for efficient photocatalytic applications

Induction and regulation of differentiation in neural stem cells on ultra-nanocrystalline diamond films

100學年度研究獎補助論文[[abstract]]The interaction of ultra-nanocrystalline diamond (UNCD) with neural stem cells (NSCs) has been studied in order to evaluate its potential as a biomaterial. Hydrogen-terminated UNCD (H-UNCD) films were compared with standard grade polystyrene in terms of their impact on the differentiation of NSCs. When NSCs were cultured on these substrates in medium supplemented with low concentration of serum and without any differentiating factors, H-UNCD films spontaneously induced neuronal differentiation on NSCs. By direct suppression of mitogen-activated protein kinase/extracellular signaling-regulated kinase1/2 (MAPK/Erk1/2) signaling pathway in NSCs using U0126, known to inhibit the activation of Erk1/2, we demonstrated that the enhancement of Erk1/2 pathway is one of the effects of H-UNCD-induced NSCs differentiation. Moreover, functional-blocking antibody directed against integrin β1 subunit inhibited neuronal differentiation on H-UNCD films. This result demonstrated the involvement of integrin β1 in H-UNCD-mediated neuronal differentiation. Mechanistic studies revealed the cell adhesion to H-UNCD films associated with focal adhesion kinase (Fak) and initiated MAPK/Erk1/2 signaling. Our study demonstrated that H-UNCD films-mediated NSCs differentiation involves fibronectin-integrin β1 and Fak–MAPK/Erk signaling pathways in the absence of differentiation factors. These observations raise the potential for the use of UNCD as a biomaterial for central nervous system transplantation and tissue engineering.[[incitationindex]]SCI[[booktype]]紙

Distances between Requirements Engineering and Later Software Development Activities: A Systematic Map

[Context and Motivation] The main role of requirements engineering (RE) is to guide development projects towards implementing products that will appeal to customers. To effectively achieve this RE needs to be coordinated with and clearly communicated to the later software development activities. [Question/Problem] Communication gaps between RE and other development activities reduce coordination and alignment, and can lead to project delays and failure to meet customer needs. [Principle ideas/results] The main hypothesis is that coordination is enhanced by proximity to RE roles and artefacts, and that distances to later activities increase the effort needed to align requirements with other development work. Thirteen RE-related distances have been identified through a systematic map of existing research. [Contribution] Reported dis-tances are mapped according to research type, RE activity and later software development activities. The results provide an overview of RE distances and can be used a basis for defining a theoretical framework