Volume 14

Flaps, as one of the lift-augmentation devices installed on aircraft, provide sufficient lift during takeoff and landing phases. By installing flaps on the wing, the wing area can be increased, and the wing curvature can be modified. by adjusting the position of the flaps, the aircraft’s aerodynamic characteristics can be regulated. This article focuses on studying the impact of forces on trailing edge flaps during takeoff. As finding the appropriate angle of deflection is a crucial factor in improving flight efficiency, this article primarily investigates the influence of flap deflection angles on the aerodynamic forces acting on the aircraft during low-speed flight. The Flow Simulation module is utilized for the analysis of the flow field. The relation between lift and tilt angle of the flap is obtained from numerical simulations. Through the analysis, for the chosen type of flaps configuration, the optimal flap angle for takeoff is 45°. This article may offer a reference for the design of flaps.

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Geography of projective varieties is one of the fundamental problems in algebraic geometry. There are many researches toward the characteristics of Chern number of some projective spaces, for example Noether’s inequalities, the theorem of Chang-Lopez, and the Miyaoka-Yau inequality. In this paper, we compute the Chern numbers of any smooth complete intersection threefold in the product of projective spaces via the standard exact sequences of cotangent bundles. Then we obtain linear Chern number inequalities for (c_1 (X)c_2 (X))/(c_1^3 (X)) and (c_3 (X))/(c_1^3 (X)) on such threefolds under conditions of d_ij≥4 and d_ij≥6 respectively. They can be considered as a generalization of the Miyaoka-Yau inequality and an improvement of Yau’s inequality for such threefolds.

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This paper delves into the revolutionary role of Building Information Modelling (BIM) technology in building deconstruction and its profound implications for sustainable development. Conventional demolition methods often neglect considerations of material reuse and environmental ramifications. BIM emerges as a versatile solution, offering sophisticated analytical tools that amplify efficiency, safety, and material traceability throughout the deconstruction process. In this paper, the lifecycle applications of BIM are further explored. Traversing from the planning stage to material handling and recycling, the important contribution of BIM to the circular economy is highlighted. Despite being in the nascent stages of adoption for building demolition, this paper posits that comprehensive integration of BIM holds the promise to fundamentally transform the construction sector, ensuring its alignment with sustainability objectives. Case studies and real-world applications are meticulously analysed to furnish empirical evidence corroborating these assertions, shedding light on the practical and environmental advantages of leveraging BIM in deconstruction.

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The rise of technology has brought with it a heightened awareness of the necessity to shield personal data and maintain exclusive access to specific knowledge. A notable solution that emerged from this consciousness is Zero-Knowledge Proofs (ZKPs) and, more specifically, Schnorr’s Protocol. Historically, Zero-Knowledge Proofs have a compelling lineage, tracing their roots back to the fervent discussions among cryptographers aiming to achieve a balance between information sharing and privacy. ZKPs are cryptographic methods that allow one party to prove to another that a statement is true, without revealing any specific information about the statement itself. In the midst of these developments, Schnorr’s Protocol emerged as a renowned interactive proof system. It possesses an intuitive structure that has made it pivotal in the enhancement of digital security. The typical flow of Schnorr’s Protocol begins with the prover sending a commitment to the verifier. The verifier then sends a random challenge back to the prover, who, in turn, produces a response. What’s captivating is that the verifier can ascertain the validity of the proof without gaining insight into the underlying secret. Interactive Schnorr’s Protocol involves real-time back-and-forth communication between the prover and verifier. On the other hand, the non-interactive version eliminates this need by using a cryptographic hash function, thereby streamlining the process.

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With the rapid growth of population in large cities, traditional transportation modes like buses, private cars, and subways have formed a more serious traffic congestion or crowded situation. In order to solve this problem, engineers and researchers start to shift the research on the future development of transportation systems to the near-ground space (NGS). The flying car transportation system (FCTS) has become one of the major research projects. The concept of FCTS introduces a new dimension to transportation, utilizing unoccupied near-ground spaces to redefine the way both individuals and goods move within cities. FCTS, using flying cars as the main transportation means, has good development prospects. This article analyzes various aspects of FCTS in detail. The design of FCTS is introduced. The related technologies are summarized. The challenges of the future development of FCTS are also discussed. This article may offer a reference for the development of FCTS.

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Formula One (F1) represents the pinnacle of automotive engineering. Aerodynamics is a critical factor that determines the performance of these high-speed racing machines. This paper aims to provide a comprehensive overview of the evolution and advancements in aerodynamic design and technology in Formula One over the years. Starting from the rudimentary designs of the 1950s, this paper traces the progression to the highly sophisticated Computational Fluid Dynamics (CFD) simulations and wind tunnel tests that dominate the sport today. Innovations like ground effects, diffusers, DRS (Drag Reduction System), and vortex generators are examined to elucidate how they contribute to increasing downforce, reducing drag, and thereby enhancing performance. This paper touches upon the future prospects of aerodynamic research in Formula One, including sustainability considerations and potential areas for innovation. Through a synthesis of historical trends, technical breakthroughs, and empirical data, this paper may provide a holistic understanding of aerodynamics in the context of Formula One racing.

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The engine is the most important part of an airplane. Since the blades of an engine are a major factor in jet engine performance, the research of engine blades has always been a hot topic in the field of aerospace. This paper summarizes the research status in the field of jet engine blades. As for the design of the jet engine blade, the design of aerofoil and the geometrical structure of the engine blade is introduced. In the material selection of engine blades, titanium alloy materials, and the application of composite materials are introduced. Electrochemical machining (ECM) and additive technology of engine blades are introduced. The differences between them and traditional casting techniques are compared. The comprehensive analysis shows that the research on engine blades is becoming more and more mature, but there are some challenges in further optimization of manufacturing technology and materials. This paper may offer a reference for the design of jet engine blade.

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Aircraft wings are designed to make airflow to travel faster on top and slower on bottom. The lift force is generated by the pressure difference between the top and bottom of the wing due to the Bernoulli principle. The downwash also provides lift due to Newtons’ third law. The wake vortex is the consequence of the production of lift. The spinning turbulent flow at the wing tip creates induced drag, and decreases the total aerodynamic efficiency of the aircraft. A wing tip device is a piece of extension of the wing attached to the wing tip vertically upward or downward. The idea of a wing tip device comes from nature, where engineers reference the wings of different types of birds. The main purpose of this design is to counter and reduce the total drag, allowing aircraft to optimize its aerodynamic performances to reduce fuel consumption. Different wing tip devices based on their structure design have various positive impacts on the aviation industry. In this article, the origin and the applications of wing-tip devices are discussed, offering a reference for the development of wing-tip devices.

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Designed for aircrafts to fly mixed missions (i.e., at subsonic, transonic, and supersonic flight speeds) with low levels of fuel consumption, the variable cycle engine is ideal for many high-speed planes. The variable cycle engine has the characteristics of both a high-bypass engine (for subsonic flight speed) and a low-bypass engine (for supersonic flight speed). As modern jet engines develop, they inevitably face a bottleneck. Therefore the VCE is seen by most as the next stage of the engines. More and more companies are beginning to invest in this new technology. This paper is targeted to explore the basic mechanism of various VCEs and to see how this new engine brings people better performance over conventional jets. Through Documental Analysis and case study, this research discovered the variable cycle engine greatly improves efficiency and reduces heat of the exiting exhaust in subsonic flight and generates higher thrust during afterburner.

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Insufficient agricultural land and a high vacancy rate in industrial buildings are important problems facing Hong Kong. Therefore, this study aims to determine whether industrial buildings are suitable as agricultural spaces and to formulate corresponding utilization strategies to promote agricultural production and food supply in Hong Kong. Research objects include industrial building space and hydroponic agricultural space. This paper used literature research and field research as the main research tools to collect relevant information on the utilization potential of industrial buildings and hydroponic agriculture. In addition, research data are derived from literature studies and surveying data, which provide detailed information about the industrial building structure and surrounding environment to better assess its suitability and feasibility. This research concludes that industrial buildings are potentially suitable for use in agricultural spaces, especially hydroponic agriculture. Its internal structure and environmental conditions can support agricultural production and effectively use vacant industrial building space to expand the scale of agricultural production. Regarding utilization strategies, this study recommends using recycling systems and related technologies, such as hydroponic systems and LED lighting, to transform industrial buildings internally to create farming communities. This will help make agricultural production more efficient and sustainable while providing cities with a fresh supply of produce.

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