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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Thermal barrier coatings (TBC) and cooling structures are critical factors influencing the performance of aviation turbine blades. In order to investigate the effects of TBC and different cooling structures on the operating temperature and thermal stress of turbine blades, this study establishes a three-dimensional fluid-thermal-solid coupling model for aviation turbine blades. Based on this model, the study analyzes the effect of TBC thicknesses and different design architectures on the blade thermal characters, including temperature distribution and thermal stress analysis. Stress analysis is also conducted on blades with the best heat dissipation performance. The results indicate that as the thickness of the TBC increases, the blade temperature gradually decreases. Cooling channels effectively reduce turbine blade temperatures. It is also found that a reasonable increase in film cooling holes can further reduce blade temperatures. The thermal stress on the blade gradually decreases along the blade height, with the high-stress regions primarily concentrated at the junction between the blade body and the margin plate. The maximum stress is observed at the trailing edge. The conclusions of this study can provide valuable guidance for the design of aviation turbine blades with better thermal performance.

China’s oil production is not as good as before, and China’s oil production has completely failed to keep up with people’s demand for oil, and the situation of relying heavily on imports needs to be changed. The conversion rate from oil to gasoline is low, which is not conducive to the utilization of raw materials. There are many unavoidable losses during the transportation of oil. The conversion rate of traditional engines in automobiles is very low, and it cannot be improved in a short period of time. The exhaust gases emitted by conventional engines can cause serious pollution to the environment. In contrast, China has abundant power resources, and the loss of electrical energy in the transmission process is also very small. Pure electric vehicle engines are highly efficient and have the potential for further improvement. Brake energy recovery is also an important part of improving efficiency. Pure electric engines bring little pollution to the environment.

This report explores using Python, a coding language, to create simulated images of a gravitational lens system, using the Hubble Space Telescope (HST) parameters. With Python’s helpful tools, like NumPy for math operations and Astropy for astronomy tasks, we build algorithms that recreate the interactions within our chosen group of galaxies and take into account HST’s unique imaging capabilities. Our method combines theory of gravitational lensing with practical coding strategies to make simulations show these complex light-bending interactions. The report walks through how the algorithms are developed with specific scientific simulation models like Sersic profile and point-spread function (PSF), showcasing the important role of computer simulations in deepening our understanding of space. In this report, I will introduce how we can use python code to create simulation images of a gravitational lens system. This system involves with 10 source galaxies ,20 lensing galaxies and with consideration of dark matter halo.

Cryptography stands as an indispensable and efficient facet within the expansive field of information security. It offers a reliable method for ensuring the confidentiality and integrity of data during the complex process of information transmission between a sender and a recipient. Beyond this, exclusive decryption privileges are meticulously reserved for the designated recipient. This individual holds the exclusive authority to decipher the transmitted information, which has been encrypted by the key holder beforehand. This scholarly investigation introduces and delves into three prevalent cryptographic algorithms: RSA, El-Gamal, and Elliptic Curve Cryptography. It offers a discerning examination and contrast of the underlying mathematical challenges associated with each sophisticated method. The discourse unfolds a detailed comparative analysis of these three pivotal algorithms, zeroing in on their crucial aspects such as key size length and operational running time. The in-depth exploration within this study aims to shed light on the intricate workings, strengths, and potential limitations of RSA, El-Gamal, and Elliptic Curve Cryptography. By unraveling these aspects, the study contributes to a richer understanding and more informed choices in the practical application of cryptographic algorithms, enhancing the overarching realm of information security in an increasingly digital and interconnected world.

The concept of infinity is intricately connected to and comprehended via the framework of cardinal and ordinal numbers. Cardinal and ordinal numbers are fundamental mathematical ideas within the field of set theory. The cardinal number is used to denote the quantity of items inside a given set while ordinal defines basic algorithms. This article demonstrates how the discipline of set theory may be used as a tool to investigate the nature of infinity, or at the very least give some insights into the subject. The idea of infinity may be better understood by looking at it through the lens of set theory and the commutative property. In addition to that, this research presents the connection and compatibility examination of Cohen’s operation upon the Zermelo Freankel axiomatic framework. These accomplishments are discussed in this article as illuminating insights for readers to consider while imagining the ultimate solution to the problems posed by the Continuum Hypothesis and the nature of infinity. Through the use of examples from contemporary researchers, the multiverse and indeterminism are introduced as potential approaches to the problem of how to solve Cantor’s legacy in the future.

A digital electronic clock is a sophisticated instrument that employs digital circuits to render the time—hours, minutes, and seconds—in a digital format. This paper delves into the intricate design journey of creating a basic digital clock using the powerful Verilog HDL paired with a seven-segment digital tube. The core objective revolves around the realization of the clock’s essential features, emphasizing both timing mechanics and its visual display. The architecture of the digital clock circuit is a seamless integration of three pivotal modules: the frequency divider, which ensures accurate time intervals; the counter, which keeps track of elapsed time; and the decoder, responsible for converting raw data into a format suitable for display. The clock’s tangible representation of time is vividly brought to life on a light-emitting diode (LED) display of the seven-segment digital tube. This setup magnificently showcases two-digit representations for hours, minutes, and seconds, streamlining the user’s experience. Rigorous simulation revealed that the system adeptly meets its operational mandate, functioning seamlessly as a digital clock and thereby aligning perfectly with the stipulated design criteria.

With the rapid development of drone technology, methods to improve drone performance have emerged endlessly. Reducing air resistance can significantly improve drones’ fight performance. The winglet is used to control the turbulence and vortices. The widespread application of winglets in the field of military and civil aviation has enabled winglets to be applied to drones to improve flight range and economic efficiency. As different winglets have different impacts on drones’ flight performance, this article focuses on the influence of different winglets on enhancing lift and reducing resistance of small civilian drones. In detail, three representative winglets are taken as the specific research objects, including the fusion winglet, the double fork scimitar winglets, and wingtip fence. The aerodynamic characteristics and the structural designs are comprehensively introduced. The importance of winglets in improving aircraft performance, energy saving and environmental protection is briefly explained. This article may offer a reference for the design of drones.

Military transport aircrafts and civil aircrafts are important parts of the aviation field. With the development of aviation technology and the specificity of aircraft functions, the design of military transport aircraft and civil aircraft gradually differs according to application scenarios. However, in the aircraft design, military transport aircrafts and civil aircrafts still have a lot of mutual references. Analyzing the differences between them and the reasons for the differences may contribute to the design and development of military transport aircraft and civil aircraft in the future, and provide reference suggestions for the design of civil aircraft in the context of the civil-military integration. In this article, the application scenarios and functions of military transport aircraft and civil aircraft are analyzed, as well as the special situation of civil aircraft research and development. This article may offer a reference for the future research and development of military transport aircraft and civil aircraft.

As the core component of electronic circuits, amplifiers play a pivotal role in fields such as communications, medical care, audio processing, instrumentation, scientific research and military technology. However, the noise problem of the amplifier has a direct impact on the reliability and accuracy of the system, how to reduce the impact of noise is crucial. This paper aims to study and solve noise problems in amplifier design. The first part focuses on the design of operational amplifiers. By adjusting the circuit structure and introducing current mirrors, the noise of the input and output stages is successfully reduced and the amplifier performance is improved. The second part focuses on the design of instrumentation amplifiers, introducing kT/C noise elimination technology, chopper modulation structure solves the noise and aliasing problems in switched capacitor instrumentation amplifiers and improve performance.

The development of integrated circuits has gone through several stages, from the invention of transistors to the emergence of very large scale integrated circuits and system level integrated circuits. Now, the size of integrated circuits enters the nanometer level, and short-channel shot noise becomes an important issue. Short-channel shot noise increases due to factors such as device size reduction and scattering during channel formation. It has a serious impact on the performance, power consumption and reliability of integrated circuits. The formation mechanism of short channel shot noise can be explained from two aspects: one is due to the existence of thermal noise inside the channel, and the other is due to the noise caused by the shot. As the device size decreases, the channel thermal noise gradually changes into shot noise and becomes one of the main noise sources. Aiming at the noise generation mechanism, this paper proposes several methods to solve the short-channel shot noise. Through the research of short-channel shot noise and the exploration of solutions, the impact of shot noise on IC performance can be better understood and dealt with, and the development and innovation of IC technology can be promoted.