Search results

The paper aims to assess the potential of aircraft operation from city centres to achieve shortened travel times and the involved aircraft design process.

The paper describes the methodical approach and iterative procedure of the design process. An assessment of potential technologies is conducted to provide the required enhancements to fulfil the constraints following an inner-city operation. Operational procedures were analysed to reduce the noise propagation through flight path optimization. Furthermore, a ground-based assisted take-off system was conceived to lower required take-off field length and to prevent engine sizing just for the take-off case. Cabin design optimization for a fast turnaround has been conducted to ensure a wide utilization spectrum. The results prove the feasibility of an aircraft developed for inner city operation.

A detailed concept for a 60-passenger single aisle aircraft is proposed for an Entry-Into-Service year 2040 with a design range of 1,500 nautical miles for a load factor of 90 per cent. Although the design for Short Take-off and Landing and low noise operation had to be traded partly with cruise efficiency, a noteworthy reduction in fuel burn per passenger and nautical mile could be achieved against current aircraft.

The findings will contribute to the evaluation of the feasibility and impact of the Flightpath 2050 goal of a 4-h door-to-door by providing a feasible but ambitious example. Furthermore, it highlights possible bottlenecks and problems faced when realizing this goal.

The paper draws its value from the consideration of the overall sizing effects at aircraft level and from a holistic view on an inner-city airport/aircraft concept design for a 4-h door-to-door goal.

The purpose of this paper is to analyse the signal dependency of the camera-based coaxial monitoring system QMMeltpool 3D (Concept Laser GmbH, Lichtenfels, Germany) for laser powder bed fusion (LPBF) under the variation of process parameters, position, direction and layer thickness to determine the capability of the system. Because such and similar monitoring systems are designed and presented for quality assurance in series production, it is important to present the dominant signal influences and limitations.

Hardware of the commercially available coaxial monitoring QMMeltpool 3D is used to investigate the thermal emission of the interaction zone during LPBF. The raw images of the camera are analysed by means of image processing to bypass the software of QMMeltpool 3D and to gain a high level of signal understanding. Laser power, scan speed, laser spot diameter and powder layer thickness were varied for single-melt tracks to determine the influence of a parameter variation on the measured sensory signals. The effects of the scan direction and position were also analysed in detail. The influence of surface roughness on the detected sensory signals was simulated by a machined substrate plate.

Parameter variations are confirmed to be detectable. Because of strong directional and positional dependencies of the melt-pool monitoring signal a calibration algorithm is necessary. A decreasing signal is detected for increasing layer thickness. Surface roughness is identified as a dominating factor with major influence on the melt-pool monitoring signal exceeding other process flaws.

This work was performed with the hardware of a commercially available QMMeltpool 3D system of an LPBF machine M2 of the company Concept Laser GmbH. The results are relevant for all melt-pool monitoring research activities connected to LPBF, as well as for end users and serial production.

Surface roughness has not yet been revealed as being one of the most important origins for signal deviations in coaxial melt-pool monitoring. To the best of the authors’ knowledge, the direct comparison of influences because of parameters and environment has not been published to this extent. The detection, evaluation and remelting of surface roughness constitute a plausible workflow for closed-loop control in LPBF.

The purpose of this paper is to develop an integrated multi-risk identification procedure for World Cultural Heritage (WCH) sites exposed to seismic events, while considering characteristics of disasters from earthquakes in a multi-hazard context on one side and particular aspects of WCH (e.g. outstanding universal values and associated condition of authenticity and integrity) on the other.

An interdisciplinary review of current relevant approaches, methods, and practices is conducted through the existing literature of disaster risk management, heritage conservation, and seismology. Furthermore, a document analysis of concrete cases affected by seismic events supports concepts and the procedure.

This paper results in a methodology of identifying multi-risk of disasters induced by earthquakes. A bow-tie analysis diagram in combination with a risk identification matrix is developed for illustrating a multiple emergency scenario in identifying possible impacts of earthquakes’ primary effects, secondary hazards, and human-threats on tangible and intangible attributes of cultural properties.

The research aims to provide specialists and practitioners from multiple sectors engaged in pre-disaster risk mitigation and preparedness plan for cultural heritage with a practical risk identification tool. The proposed method, in a multiple hazard context, intends to enhance risk assessment procedure for determining more appropriate risk reduction strategies in the decision-making process.

This paper, through emphasising “earthquake disaster risk” rather than “earthquake risk”, illuminates the significance of quake-followed secondary hazards, potential human-induced hazards and human errors in the risk identification process, due to the fact that while a disaster may begin with a quake, its full scope might be triggered by a combination of the mentioned potential threats.

Recently, we (Judiesch, Schmidt, & Mount, 1992) concluded that the Schmidt et al. (1979) SDy estimation procedure results in downwardly biased estimates of utility. This conclusion led us to propose a modification of the Schmidt et al. method that involves estimating SDy as the product of estimates of the coefficient of variation (SDy/ Y) and an objective estimate of the average value of employee output (Y). The present article reviews the rationale underlying our conclusion that this modification of the Schmidt et al. method of estimating SDy results in more accurate estimates of SDy, and hence, utility.

The purpose of this paper is to propose a low-cost, high return model for implementing a programmatic foresight function that is collaboratively integrated with the organization’s existing policy, planning and intelligence (or policy research) functions. Focusing on government agencies, especially those supporting liberal democratic governments, the purpose of the current paper is to propose a new, practical, low-cost and high-return model for implementing a programmatic strategic foresight function that is collaboratively integrated with the organization’s existing policy, planning and intelligence functions. The paper describes the relevant organizational considerations and options for structural adjustments, and suggests how the proposed model can maximize decision-making effectiveness without disrupting pre-existing structures, operations and products. The paper further discusses the necessity and involvement of a central government foresight agency and a non-hierarchical distributed network linking the foresight units.

Possible solutions are considered with respect to costs of development and implementation, risk (likelihood, consequence and uncertainty) of the new function’s failure, direct negative or positive effect on the performance of existing functions, the level of cross-organizational involvement in or collaboration with the new function, the level of cross-organization tangible benefits and the level of vertical involvement, especially at the executive level.

With few exceptions, the implementation of foresight by governments has not been at all methodical, but has followed many different paths, where it has occurred at all. The approach proposed in this paper – establishing a central foresight agency, propagating individual agency-based small programmatic foresight units and virtual teams and creating a non-hierarchical distributed network to link all of them – appears to best meet the success criteria set out in the paper.

Governments, especially liberal democratic ones, and their agencies that have previously shied away from methodically implementing strategic foresight or that have attempted to do so without real success now have an approach that is likely to produce the desired results.

The paper creates a sound framework for governments, especially liberal democratic ones, and their agencies to consider and proceed with the implementation of foresight functions and networks to support them.

The proposed approach is entirely new and generally challenges current practices.

The purpose of this paper is to demonstrate the processability of cohesive PE-HD particles in laser beam melting processes (LBM) of polymers. Furthermore, we present a characterization method for polymer particles, which can predict the quality of the powder deposition via LBM processes.

This study focuses on the application of dry particle coating processes to increase flowability and bulk density of PE-HD particles. Both has been measured and afterwards validated via powder deposition of PE-HD particles in a LBM machine.

For efficient coating in a dry particle coating process, the PE-HD particles and the attached nanoparticles need to show similar surface chemistry, i.e. both need to behave either hydrophobic or hydrophilic. It is demonstrated that dry particle coating is appropriate to enhance flowability and bulk density of PE-HD particles and hence considerably improves LBM processes and the resulting product quality.

At present, in LBM processes mainly polyamide (PA), 12 particles are used, which are so far quite expensive in comparison to, for example, PE-HD particles. This work provides a unique and versatile method for nanoparticulate surface modification which may be applied to a wide variety of materials. After the coating, the particles are applicable for the LBM process. Our results provide a correlation between flowability and bulk density and the resulting product quality.

This paper sets out to assess and analyses the key pillars of the SEA framework in Kenya, highlighting aspects that should be considered for further scrutiny and review, aiming at evolving a suitable context‐specific Kenyan SEA.

Content analysis of the SEA framework was done through desktop research. This was supplemented by a two‐month internship at the National Environmental Management Authority in Kenya. The key documents prescribing and describing SEA in Kenya (legal documents, guidelines) formed a basis for interpretative analysis. International literature on SEA frameworks also formed a basis for analysis.

Although the SEA framework is relatively complete, there are certain elements that are incomplete, e.g. environmental and sustainability standards have not been formally established. Some provisions are unclear or reveal internal incoherency within the framework. For example, the definitions of policies, plans, programmes and projects are not clearly differentiated for the purpose of the SEA framework. The framework is premised on “an early SEA” yet the key exercises of public participation and the triggering of the SEA exercise are both carried out late. There is need for SEA‐EIA tiering and SEA definitions and purposes to be harmonized within the various documents of the framework. Sector‐level SEA guidelines offer the most appropriate opportunity to address most of the substantive shortcomings of the framework.

The results provide a baseline for departure towards further scrutiny and research in order to evolve a more homegrown SEA, as opposed to merely copyng what other countries have done. The highlighted areas are expounded on, with some suggestions given; in some instances no clear remedy is immediately obvious.

The paper is a seminal instigator of interest into the Kenyan SEA framework, which is still very young and devoid of experience and tradition. It brings to light and questions some key issues that seem to have the potential to reduce the benefits and instrumentality of the SEA tool in meeting Kenya's interest.

The purpose of this paper is to report on the outreach activities of the Fine Arts Library at Ohio State University.

Outreach at Ohio State is intended to have global impact, but successful outreach is often hampered by lack of partnerships, funding restrictions, and a monolithic approach to the patron. The paper reflects on each of these issues and discusses the strategies used by the Fine Arts Library to conduct outreach with user‐focus and budgets in mind.

The paper finds that there are techniques for outreach that involve small outputs of funds but have larger impacts. Moving past a “one size fits all” philosophy for outreach allows the Fine Arts Library to connect with the patrons it is best able to serve.

While the phrase “think globally, act locally” is well‐known, it can often be forgotten in libraries, where the goal to reach as many people as possible is very important. This paper suggests that the returns on the local investment are incredibly important to the global missions of libraries.