Search results

The purpose of this paper is to explore the possibilities of introducing a number of visionary and pioneering ideas and upcoming enabling technologies for a conceptual and aerodynamic design of green business jet aircraft to meet various requirements within Green and N + 2 Aircraft framework, and at the same time, to meet the requirements of air transportation demand, economic growth and environmental conservation.

A synthesis of various aircraft design methodologies has been carried out through iterative optimization to arrive at the conceptually designed aircraft with novel concept with optimum performance within the subsonic flight regimes. Major ideas derived from D8 and other novel concepts are appropriately applied in the work, which starts with fuel efficient motivation, and followed by wing aerodynamics and other critical factors related to the design requirements and objectives.

Through a meticulous effort following the synthesized design methodologies in the conceptual design phase, a conceptual design of a quad-bubble business jets with a set of specifications that meet the green and N + 2 aircraft technology requirements and exhibit promising performances is proposed and assessed within recent aircraft technology development.

The research work is limited to conceptual design and analytical work which should be followed by further iterative steps incorporating experiments and detailed structural and aerodynamic computations.

The conceptual design proposed can be utilized as a baseline for further practical step in an aircraft development project.

The conceptual design proposed could be utilized for business and economic study for future air transportation system.

The work is original, incorporating review of state-of-the-art technology, environmental requirements and a synthesis of a novel product.

A multiperiod analysis of working capital investment is outlined. An attempt is also made to clarify the objects of working capital management by reference to wealth maximisation orthodoxy.

Binder jetting (BJ) process is an additive manufacturing (AM) process in which powder materials are selectively joined by binder materials. Products can be manufactured layer-by-layer directly from three-dimensional model data. The quality properties of the products fabricated by the BJ AM process are significantly affected by the process parameters. To improve the product quality, the optimal process parameters need to be identified and controlled. This research works with the 420 stainless steel powder material.

This study focuses on four key printing parameters and two end-product quality properties. Sixteen groups of orthogonal experiment designed by the Taguchi method are conducted, and then the results are converted to signal-to-noise ratios and analyzed by analysis of variance.

Five sets of optimal parameters are concluded and verified by four group confirmation tests. Finally, by taking the optimal parameters, the end-product quality properties are significantly improved.

These optimal parameters can be used as a guideline for selecting proper printing parameters in BJ to achieve the desired properties and help to improve the entire BJ process ability.

The purpose of this study is to investigate the effect of two unique processing routes (solvent jetting (SJ) and binder jetting (BJ)), on the green density of printed stainless steel 316L (SS316L) and Nickel (Ni) powders.

In the SJ processing route, a solvent is jetted unto the powder/binder mixture to selectively activate the binder, layer by layer. In the BJ processing route, a solution of the binder mixture is jetted onto the powder bed to selectively bind powder particles. The effects of printing parameters such as layer height, roller speed, shaker speed and nozzle temperature on the green density of printed components are investigated and compared for both processing routes.

Results show that layer height and nozzle temperature affect the relative density of the printed compact for both processing routes. Slightly higher relative densities were achieved via the SJ route, with the overall highest relative density being 42.7% at 100 µm layer height and 70% nozzle temperature for the SS316L components and 43.7% at 150 µm layer height and 90% nozzle temperature for the Ni components, respectively. Results also show an increase in the final sintered relative density with an increase in green (printed) relative density of the solvent jetted SS316L components, with the highest relative density being 87.2%.

The paper studies the influence of printing parameters on the green density of printed SS316L and Ni samples in an unprecedented effort to provide a comparative understanding of the process-property relationships in BJ and SJ of SS316L and Ni components to the additive manufacturing research community.

We have conducted a study of academic faculty use of databases for research, their need for evaluative guides to databases, and the appropriateness of currently‐available guides. Although the response rate was low (19%), the follow‐up survey suggested only a minimal non‐response bias. Our findings suggest that academic faculty are typically unaware of the range of databases available and few recognize the need for databases in research. Of those faculty who do use databases, most delegate the searching to a librarian or an assistant, rather than performing the searches themselves. We identified thirty‐nine database guides; these tend to be descriptive rather than evaluative.

Dahlia is an ornamental plant originating from Mexico where it is considered as the National flower. The purpose of this paper is to investigate tubers from yellow, white and red‐flowered cultivars of the common garden Dahlia (D. pinnata) for their chemical composition.

The composition of minerals was determined using Atomic Absorption Spectrometry (AAS), whereas vitamins were analyzed by High‐Performance Liquid Chromatography (HPLC).

Carbohydrates represented the major constituent in Dahlia tubers, followed by fibre and protein. Tubers of the yellow‐flowered cultivar “HGH” contained the highest amount of carbohydrates, while tubers of the white‐flowered cultivar “BJ” and those of the red‐flowered cultivar “XM” abounded in fibre and protein, respectively. In addition, Dahlia tubers exhibited varying concentrations of minerals, among which potassium, calcium, magnesium, phosphorus, zinc and chromium were predominant. Tubers of the white‐flowered cultivar “LB” contained the highest amounts of magnesium and phosphorus. Moreover, tubers of the red‐flowered cultivar “MLH” showed the highest contents of potassium and chromium, whereas those of the red‐flowered cultivar “XM” were rich in calcium and zinc. Furthermore, Dahlia tubers were found to contain water and fat soluble vitamins, among which vitamins B2, B6, B7 and E were the most abundant. Tubers of the white‐flowered cultivar “BJ” exhibited the highest contents of water soluble vitamins, whereas those of the white‐flowered cultivar “LB” abounded in fat soluble vitamins.

Despite the considerable variability observed among cultivars, Dahlia might be utilized as an alternative food resource for human nutrition.

In this paper, to obtain shear and bending performance of carbon fiber-reinforced polymer (CFRP)-strengthened beams bonded by geopolymers, the effects of impregnated adhesive types, strengthened scheme, CFRP layer and pre-cracked width are investigated, and the performance of CFRP-strengthened beams is validated by the establishment of Finite Element Models (FEMs).

In this paper, static loading test and finite element analysis of epoxy-CFRP-strengthened (ECS) and geopolymer-CFRP-strengthened (GCS) were carried out, and the bearing capacity and stiffness were compared, the results show that GCS reinforced concrete (RC) beam is feasible and effective.

The bearing capacity, crack distribution and development, load–deflection curves of GCS RC beams with different pre-crack widths were investigated. The reinforcement effect of geopolymer achieves the same as epoxy, effectively improving the ultimate bearing capacity of the beam, with a maximum increase rate of 28.9%. The failure mode of CFRP is broken in the yield failure stage of GCS RC beam with reasonable strengthening form, and the utilization rate of CFRP is improved. CFRP-strengthened layers, pre-cracked widths significantly affect the mechanical properties, and deformation properties of the strengthened beams.

Compared with ECS RC beams, the bearing capacity and stiffness of GCS RC beams are similar to or even better, indicating that GCS RC beam is feasible and effective. It is a new method for CFRP-strengthened beams, which not only conforms to the concept of national ecological civilization construction, but also provides an economical, environmentally friendly and excellent performance solution for structural reinforcement.

Many e-commerce firms suffer from high returns because of inaccurate and incomplete product information. Omnichannel and bundling settings can help firms improve operational efficiency and lower returns costs. However, no studies have been conducted on omnichannel supply chains considering bundling strategies. The purpose of this study is to examine the comparison between test-in-store-and-buy-online (TSBO) and online retail, comparing manufacturers’ bundling with retailers’ bundling.

The supply chain discussed here consists of two competitive manufacturers and one retailer. The retailer sells both manufacturers' products online and displays one manufacturer's product in a showroom who bears the display cost. Stackelberg game theory is used to develop mathematical models that help manufacturers and retailers make the most effective decisions. Here, the manufacturer is the Stackelberg leader, while the retailer is the follower. Using the backward induction approach, the authors determined the optimal values for selling price, wholesale price and service effort level.

The results show that the total TSBO retailing profit under manufacturer bundling is highest when the second manufacturer integrates with the online retailer. The result additionally establishes that when the bundling cost exceeds a certain threshold (1.5), the total profit is higher for the non-integrated type of supply chain channel as compared to the integrated retailer bundling-based configuration.

The operations and logistics manager will likely undertake the TSBO omnichannel strategy during manufacturers bundling and retailer bundling under the integrated strategy.

The main contribution of the study is to examine the effect of TSBO retailing on supply chains profit and individual decision-making under different bundling strategies. The authors developed different mathematical models in the TSBO retailing and bundling context and extended the earlier work in the area of integration frame.

In this paper, we present a proposed information environment (PROPIE) for enhanced interaction and value‐adding of electronic documents (e‐documents). The design of PROPIE was based on a thorough user needs and requirements assessment in interacting with information through well‐documented findings, and a focus group with twelve participants to elicit features that were deemed desirable in future interactions. The design was also based on an earlier work which reviewed the advancements in various user interface (UI) technologies, visualisation and interactive techniques, and a consideration of novel information structuring and organisation techniques that pose important implications for the design of more advanced UIs. Providing a suite of novel features and interactive tools that can be flexibly combined, PROPIE allows users to apply multiple novel ways to query intuitively and navigate information in an e‐document. The querying and browsing processes in PROPIE are supported by various interactive and visualisation techniques. Users work within a visually sovereign, integrated environment for information gathering and organising, based on navigable, fractional information objects that are also affiliated with rich metadata and additional layers of value‐adding information. A set of interface mock‐ups was developed to demonstrate the potential of the environment in supporting the design of a new generation of electronic journals (e‐journals). We report here empirical results from a study conducted to obtain representative users‘ feedback with regard to using PROPIE for interacting with e‐journals. Twenty‐two participants from a variety of academic backgrounds participated in the evaluation. Overall, PROPIE was found to have the potential both for enhancing the user’s interaction with information captured within e‐journals and for adding value to e‐documents in various ways.