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The pivotal aspect of aircraft assembly lies in precise measurement accuracy. While a solitary digital measuring tool suffices for analytical and small surfaces, it falls short for extensive synthetic surfaces like aircraft fuselage panels and wing spars. The purpose of this study is to develop a “combined measurement method” (CMM) that enhances measurement quality and expands the evaluative scope, addressing the limitations posed by singular digital devices in meeting measurement requirements across various aircraft components.

The study illustrated the utilization of the CMM by combining a laser tracker and a portable arm-measuring machine. This innovative approach is tailored to address the intricate nature and substantial dimensions of aircraft fuselage panels. The portable arm-measuring machine performs precise scans of panel components, while common points recorded by the laser tracker undergo coordinate conversion to reconstruct the fuselage panel’s shape. The research outlines the CMM’s measurement procedure and scrutinizes the data processing technique. Ultimately, the investigation yields a deviation vector matrix and chromatogram deviation distribution, pivotal in achieving enhanced measurement precision for the novel CMM device.

The use of CMM noticeably enhances fuselage panel assembly accuracy, concurrently reducing assembly time and enhancing efficiency compared to conventional measurement systems.

The research’s practical implication lies in revolutionizing aircraft assembly by mitigating accuracy issues through the innovative digital CMM for aircraft synthetic structure type product (aircraft fuselage panel). This ensures safer flights, reduces rework and enhances overall efficiency in the aerospace industry.

Introducing a new aircraft assembly accuracy compensation method through digital combined measurement, pioneering improved assembly precision. Also, it enhances aerospace assembly quality, safety and efficiency, offering innovative insights for optimized aviation manufacturing processes.

Collaborative robots (cobots) are widely used in various manipulation tasks within complex industrial environments. However, the manipulation capabilities of cobot manipulation planning are reduced by task, environment and joint physical constraints, especially in terms of force performance. Existing motion planning methods need to be more effective in addressing these issues. To overcome these challenges, the authors propose a novel method named force manipulability-oriented manipulation planning (FMMP) for cobots.

This method integrates force manipulability into a bidirectional sampling algorithm, thus planning a series of paths with high force manipulability while satisfying constraints. In this paper, the authors use the geometric properties of the force manipulability ellipsoid (FME) to determine appropriate manipulation configurations. First, the authors match the principal axes of FME with the task constraints at the robot’s end effector to determine manipulation poses, ensuring enhanced force generation in the desired direction. Next, the authors use the volume of FME as the cost function for the sampling algorithm, increasing force manipulability and avoiding kinematic singularities.

Through experimental comparisons with existing algorithms, the authors validate the effectiveness and superiority of the proposed method. The results demonstrate that the FMMP significantly improves the force performance of cobots under task, environmental and joint physical constraints.

To improve the force performance of manipulation planning, the FMMP introduces the FME into sampling-based path planning and comprehensively considers task, environment and joint physical constraints. The proposed method performs satisfactorily in experiments, including assembly and in situ measurement.

The current research conducts a comprehensive review on FishBAC (fishbone active camber morphing wing surfaces) for researchers and scientists and sheds light on challenges and opportunities of FishBAC development.

This is a review article and this study reviews previous research on FishBAC.

The current FishBAC applications could be upgraded into more efficient designs in materials, design and mechanisms with more perspectives involved. Then, this promising branch of morphing surface design could be integrated with rotor blades, unmanned aerial vehicle wings, general aviation aircraft surfaces and so on.

This is a review article.

The contributions of the study are summarized as follows: to provide an overview of FishBAC research; to compare various approaches and trends in FishBAC designs; to address the research gap in the roadmap for FishBAC design; and to discuss the challenges and opportunities of FishBAC development.

To the best of the authors’ knowledge, this is the first review on a promising morphing method and an alternative for conventional flaps and ailerons.

Blockchain is the fastest-growing technology currently being used in the aviation industry, especially in aviation maintenance, repair and overhaul (MRO) services. This study aims to create an analytic framework to assess the main factors and subfactors that have significantly influence the blockchain used in aviation MRO services. A mixed-methods approach is used to gain a comprehensive understanding of how blockchain is being adopted in aircraft maintenance facilities, Semi-structured interviews and questionnaires are used to gather data. The questionnaire is focused on the present state of the MRO industry.

Based on the literature review, a framework including four factors and 12 subfactors is developed, and the analytic hierarchy process (AHP) is then established. This study explores how these factors influence the implementation of blockchain in aviation MRO services. The five aviation MRO services providers in Taiwan, namely, “Evergreen Aviation Technologies Corporation,” “Taiwan Aircraft Maintenance and Engineering Co., Ltd.,” “Air Asia Company Ltd.,” “Aerospace Industrial Development Corp.” and “GE Evergreen Engine Services Corporation” are considered; furthermore, 55 experts working in these organizations were invited to evaluate the relative importance criteria in the AHP framework.

The results indicate that “inventory management” is the most important criterion, followed by “provisioning, procurement and sales” and “maintenance planning.” In addition, the three most important subfactors are “parts interchangeability,” “customer stock” and “SPEC2K interface for ATA SPEC 2000.”

Asia is ranked as the second most important aviation MRO service market in the world. Taiwan has the shortest flight hours in the western Pacific region, the seven major foreign cities in this area. Aviation MRO service providers located in Taiwan are the best choices for aircraft MRO in the Asia-Pacific region, indicating that Taiwan serves as a promising market development evaluation model for blockchain aviation MRO services. The results offer a comprehensive overview of the relative importance of different criteria for MRO services that use blockchains. In addition, the findings present the market potential for key players in the aviation industry, including aircraft engineers, airline companies, aircraft component manufacturers and aviation MRO service providers.

This chapter examines World War II and its impact on international and military law. It covers the war’s key crimes, the Nürnberg and Tokyo tribunals, and the creation of the United Nations, the Four Geneva Conventions of 1949, and the Genocide Convention of 1948.

This chapter examines how the nature of World War I catalyzed significant changes in the laws of war, the Treaty of Versailles, the failed Leipzig Trials, and the multiple treaties enacted in the 1920s, with particular focus on the Geneva Convention of 1929.

This study aims to evaluate the enhancement in prosthetic supply chain capabilities resulting from the implementation of additive manufacturing (AM) technologies. The study presents an emerging model outlining the key areas that undergo changes when integrating 3D printing technologies into the prosthetic supply chain.

Employing a qualitative approach, data were collected through field observations and 31 in-depth interviews conducted within various Jordanian organizations associated with the prosthetic industry and 3D printing technologies.

The findings suggest that the adoption of 3D printing technologies improves the prosthetic supply chain’s capabilities in terms of customization, responsiveness, innovation, environmental sustainability, cost minimization and patient empowerment. The study sheds light on the specific areas affected in the prosthetic supply chain following the adoption of 3D printing technologies, emphasizing the overall improvement in supply chain capabilities within the prosthetic industry.

This study provides recommendations for governmental bodies and prosthetic organizations to maximize the benefits derived from the use of 3D printing technologies.

This study contributes as the first of its kind in exploring the impact of 3D printing technology adoption in the Jordanian prosthetic industry, elucidating the effects on the supply chain and identifying challenges for decision-makers in an emerging market context.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.

Harmonic drives are used widely in aviation, robotics and instrumentation due to their benefits including high transmission ratio, compact structure and zero backlash. One of the common faults of a harmonic drive is the axial movement of the input shaft. In such a case, its input shaft moves in the axial direction relative to the body of the harmonic drive. The purpose of this study is to propose two fault diagnosis methods based on the current signal of the driving servomotor for the axial movement failure in terms of input shafts of harmonic drives.

In the two proposed fault diagnosis methods, the wavelet threshold algorithm is firstly used for filtering noises of the motor current signal. Then, the feature of the denoised current signal is extracted by the empirical mode decomposition (EMD) method and the wavelet packet energy-entropy (WPEE) theory, respectively, obtaining two kinds of feature sets. After a deep learning model based on the deep belief network (DBN) is constructed and trained by using these feature sets, we finally identify the normal harmonic drives and the ones with the axial movement fault.

In contrast to the traditional back propagation (BP) neural network model and support vector machine (SVM) model, the fault diagnosis methods based on the combination of the EMD (as well as the WPEE) and the DBN model can obtain higher accuracy rates of fault diagnosis for axial movement of harmonic drives, which can be greater than or equal to 97% based on the data of the performed experiment.

The authors propose two fault diagnosis methods based on the current signal of the driving servomotor for the axial movement failure in terms of input shafts of harmonic drives, which are verified by the experiment. The presented study may be beneficial for the development of self-diagnosis and self-repair systems of different robots and precision machines using harmonic drives.

This paper aims to discuss the adequacy of restrictive measures. Providing a synopsis of a global movement toward the imposition of target restrictive measures. Questioning the success of targeted restrictive measures in obtaining behavioural change. Identifying a reversion to the implementation of wide ranging sectoral restrictive measures in an attempt to encourage immediate behavioural change. Accessing the success of using restrictive measures to encourage democratic regimes in Africa.

This study is a desktop research that examines European Parliament and Council issued Regulations for the jurisdictions of Iran, Russia and Belarus. Academic research is also used in identifying a pendulum swing by global legislatures with respect to the imposition of targeted measures to requiring the imposition of additional wide ranging sectoral measures.

Targeted measures can be circumvented using non-hostile third countries. Academic research identifies that wide reaching sectoral sanctions encourage regime change. Therefore, where targeted measures fail to give rise to their desired persuasive objectives. The legislator moves to introduce additional measures, also comprising of sectoral sanctions. Sectoral sanctions have been applied by the European Union in Iran, Russia and Belarus. The USA has taken measures to limit Russia ability to use Turkey as a transshipment hub. The African continent case study identifies the importance of creating an architecture founded on upholding positive governance and human rights standards. Failure to do so leads to a revolving system of authoritarian regimes, sanctioned by restrictive measures.

This paper is a desktop review composed by the author.