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While computational methods are prevalent in aircraft conceptual design, recent advances in mechatronics and manufacturing are lowering the cost of practical experiments. Focussing on a relatively simple property, the lift curve, this study aims to increase understanding of how basic aerodynamic characteristics of a complex stealth configuration can be estimated experimentally using low-cost equipment, rapid prototyping methods and remotely piloted aircraft.

Lift curve estimates are obtained from a wind tunnel test of a three-dimensional-printed, 3.8%-scale model of a generic fighter and from flight testing a 14%-scale demonstrator using both a simple and a more advanced identification technique based on neural networks. These results are compared to a computational fluid dynamics study, a panel method and a straightforward, theoretical approach based on radical geometry simplifications.

Besides a good agreement in the linear region, discrepancies at high angles of attack reveal the shortcomings of each method. The remotely piloted model manages to provide consistent results beyond the physical limitations of the wind tunnel although it seems limited by instrumentation capabilities and unmodelled thrust effects.

Physical models can, even though low-cost experiments, expand the capabilities of other aerodynamic tools and contribute to reducing uncertainty when other estimations diverge.

This study highlights the limitations of commonly used aerodynamic methods and shows how low-cost prototyping and testing can complement or validate other estimations in the early study of a complex configuration.

Technology parks (TPs) are used as a tool to improve economic outlook of the region through innovation generation. This study aims to evaluate the perception of tenants of TPs to determine the gap in the expectation and identify types of firms preferring to locate in a TP.

This is the first study in Pakistan to collect data about perceived benefits of TPs in Pakistan from the decision-makers of 110 tenant firms. The cluster analysis and lift ratios are used to draw statistical inferences.

The firms can be classified into three clusters – commercial-orientation firms, science and technology-oriented firms and young tech firms – with distinct needs for survival and growth in a TP. Moreover, TPs should not just be treated as property projects for providing support services, also knowledge sharing, training and development opportunities and proximity to hubs of knowledge and markets is vital to attract a variety of industry.

Academia and policymakers have been equally interested in the potential impacts of these innovation hubs. However, there have been lack of empirical evidence on how and what to offer the incumbents of these TPs. The government of Pakistan is trying to build more TPs for promoting business activities under CPEC. Therefore, it is extremely important to determine the needs of tenants of TPs for successful utilization of huge amount of public money to be invested in TPs.

THE lift coefficient of an aerofoil fitted with a hinged control flap and a tab can be expressed in the form:

An estimate is made of the effect of adding a small forward fin on the lift and centre of pressure of a slender wing‐body combination. The fin is assumed to discharge a trailing vortex which interacts with the main lifting surface. Design charts permit rapid estimation of lift loss and centre of pressure movement for a delta wing plus body. At the lower angles of attack, the lift loss on the wing is approximately equal to the lift of the forward surface itself. Most of the lift is lost at the front of the wing, and so wing centre of pressure moves aft with addition of the forward fin. Theoretical estimates are in general agreement with experimental results at Mach numbers 1·65 and 2·41.

Precast wall lifting during prefabricated building construction faces multiple non-lean problems, such as inaccurate lifting-time estimation, unreasonable resource allocation and improper process design. This study aims to identify the pathways for improving lifting performance to advance lean construction of prefabricated buildings.

This study developed a methodological framework that integrates the discrete event simulation method, the elimination, combination, rearrangement and simplification (ECRS) technique and intelligent optimization tool. Two schemes of precast wall lifting, namely, the enterprise's business as usual (BAU) and enterprise-leading (EL) schemes, were set to benchmark lifting performance. Furthermore, a best-practice (BP) scheme was modeled from the perspective of lifting activity ECRS and resource allocation for performance optimization.

A real project was selected to test the effect of the methodological framework. The results showed that compared with the EL scheme, the BP scheme reduced the total lifting time (TLT) by 6.3% and mitigated the TLT uncertainty (the gap between the maximum and minimum time values) by 20.6%. Under the BP scheme, increasing the resource inputs produces an insignificant effect in reducing TLT, i.e. increasing the number of component operators in the caulking subprocess from one to two only shortened the TLT by 3.6%, and no further time reduction was achieved as more component operators were added.

To solve non-lean problems associated with prefabricated building construction, this study provides a methodological framework that can separate a typical precast wall lifting process into fine-level activities. Besides, it also identifies the pathways (including the learning effect mitigation, labor and machinery resource adjustment and activities’ improvement) to reducing TLT and its uncertainty.

This pragmatic research paper aims to unravel the smart vision-based method (SVBM), an AI program to correlate the computer vision (recorded and live videos using mobile and embedded cameras) that aids in manual lifting human pose deduction, analysis and training in the construction sector.

Using a pragmatic approach combined with the literature review, this study discusses the SVBM. The research method includes a literature review followed by a pragmatic approach and lab validation of the acquired data. Adopting the practical approach, the authors of this article developed an SVBM, an AI program to correlate computer vision (recorded and live videos using mobile and embedded cameras).

Results show that SVBM observes the relevant events without additional attachments to the human body and compares them with the standard axis to identify abnormal postures using mobile and other cameras. Angles of critical nodal points are projected through human pose detection and calculating body part movement angles using a novel software program and mobile application. The SVBM demonstrates its ability to data capture and analysis in real-time and offline using videos recorded earlier and is validated for program coding and results repeatability.

Literature review methodology limitations include not keeping in phase with the most updated field knowledge. This limitation is offset by choosing the range for literature review within the last two decades. This literature review may not have captured all published articles because the restriction of database access and search was based only on English. Also, the authors may have omitted fruitful articles hiding in a less popular journal. These limitations are acknowledged. The critical limitation is that the trust, privacy and psychological issues are not addressed in SVBM, which is recognised. However, the benefits of SVBM naturally offset this limitation to being adopted practically.

The theoretical and practical implications include customised and individualistic prediction and preventing most posture-related hazardous behaviours before a critical injury happens. The theoretical implications include mimicking the human pose and lab-based analysis without attaching sensors that naturally alter the working poses. SVBM would help researchers develop more accurate data and theoretical models close to actuals.

By using SVBM, the possibility of early deduction and prevention of musculoskeletal disorders is high; the social implications include the benefits of being a healthier society and health concerned construction sector.

Human pose detection, especially joint angle calculation in a work environment, is crucial to early deduction of muscoloskeletal disorders. Conventional digital technology-based methods to detect pose flaws focus on location information from wearables and laboratory-controlled motion sensors. For the first time, this paper presents novel computer vision (recorded and live videos using mobile and embedded cameras) and digital image-related deep learning methods without attachment to the human body for manual handling pose deduction and analysis of angles, neckline and torso line in an actual construction work environment.

A method has been developed for computing aerodynamic loads on slender missiles with complicated cross‐sections. This method has been applied to the prediction of loads for missiles with folding wings. Comparison of theoretical calculations with supersonic wind‐tunnel measurements indicates that the method should provide satisfactory first estimates of the aerodynamic properties of missiles with folding wings. A series of design charts is presented to allow rapid estimation of lift, folding moment and span loading for a wide variety of folding‐wing configurations.

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.

With the advancements in electric vertical take-off and landing (eVTOL) aircraft technology such as batteries, mechanisms, motors, configurations and so on, designers and engineers are encouraged to create unique and unconventional configurations of eVTOL aircraft to provide better capabilities and higher efficiencies to compete in the market. The box fan-in-split-wing tiltrotor eVTOL aircraft is an innovative design that aims to address the aerodynamic inefficiencies such as propeller effects in cruise and engine mounts drag that existed in traditional eVTOL aircraft designs such as vectored thrust, rotorcraft, lift + cruise and multi-copter configurations. This paper aims to propose a multi-disciplinary design process to conceptually design the box fan-in-split-wing Tiltrotor eVTOL aircraft.

An unconventional methodology was used to design the UAM aircraft, and the following parameters are considered: capable of vertical take-off and landing, highly aerodynamic with a high lift-to-drag ratio, low Cd₀ modern and appealing, rechargeable or battery swappable and feature to minimise or negate propeller drag. A heavy emphasis on improving performance and weight based on aerodynamics was enforced during the conceptual design phase. MAPLA and XFOIL were used to identify the aerodynamic properties of the aircraft.

Upon determining the key parameters and the mission requirements and objectives, a list of possible VTOL configurations was derived from theoretical and existing designs. The fan in the wing/split wing was selected, as it could stow the propellers. A tiltrotor configuration was selected because of its ability to reduce the total number of lift props/motors, reducing powerplant weight and improving aerodynamic efficiency. For the propulsion configuration, a battery–motor configuration with a hexa-rotor layout was chosen because of its ability to complement the planform of the aircraft, providing redundant motors in case of failure and because of its reliability, efficiency and lack of emissions. Coupled with the fan-in-wing / split wing concept, the box wing seamlessly combines all chosen configurations.

The box fan-in-split-wing Tiltrotor eVTOL aircraft aims to address the aerodynamic inefficiencies of earlier designs such as propeller effects in cruise and engine mounts drag. The potential benefits of this aircraft, such as increased range, endurance and payload capacity, make it an exciting prospect in the field of Urban Air Mobility.

The purpose of this paper is to propose a methodology to determine the designing parameters for solar powered high‐altitude, long‐endurance (HALE) unmanned aerial vehicles (UAV).

By depicting solar power distribution on earth, along with the efficiencies analysis of photo‐voltaic cells (P‐cell) and lithium‐sulfur battery (LS‐battery), the influence of energy to concept design parameters is analyzed first. Second, the lift efficiency is determined from ground to 20 km for HALE UAV. Third, the methodology to determine design parameters for HALE UAV is generalized by analyzing the carrying ability of some famous HALE UAVs, such as Zephyr, Helios, and so on.

Energy is the key constraint on design of HALE UAV. The questions about where HALE UAVs are capable of operating and how long they could work can be answered according to power density distribution on earth. The total mass of HALE UAV can be divided into two parts: one is the constant mass, the other is the mass increasing with area of wing. The total mass can be estimated by the former one; the later one plays an important role in estimating wing load in the designing process.

The only way to enhance carrying ability of HALE UAVs is to redistribute their wing load: lighter structure materials and a better method to fix P‐cell with lighter fundus are the key technologies to enhance HALE UAVs’ carrying ability. At current technological levels, it is not easy to design a UAV to achieve the aim of high‐altitude long‐endurance.

This paper presents a very efficient and convenient method to determine the designing parameters of HALE UAV.