bluuebunny/crossref_metadata_2025 huggingface dataset:
Hidradenite Supurativa: influência da alimentação sob a perspectiva dos pacientes
Authors: Souza Fernanda Oliveira , Sá Clara Cecília Ribeiro de , Pires Liliane Viana , Oliveira Pedro Dantas , Fagundes Andhressa Araújo
Published: August 2023

Objetivo: Caracterizar os hábitos de vida e alimentação dos pacientes de Hidradenite Supurativa. Métodos: Estudo transversal, quantitativo, com aplicação de questionário estruturado on-line, com dados sociodemográficos, clínicos e o consumo alimentar associado à melhora ou piora do curso da doença. Aplicou-se o teste Qui-Quadrado com valor de p<0,05. Resultados: Participaram do estudo 268 pacientes com idade média de 30,9 (± 9,4) anos, a maioria era do sexo feminino (90,3%), presença de excesso de peso (68,6%), estágios II (55,6%) e III (27,6%) da classificação de Hurley. A dor intensa foi reportada por 76,5% dos participantes e 67,5% obtiveram mais que 10 pontos no Dermatology Life Quality Index. Na perspectiva dos pacientes, os alimentos in natura, como frutas e verduras (43,3%) e carnes brancas (29,9%), melhoram os sintomas, enquanto laticínios (61,9%), doces (61,9%) e fast foods (60,8%) costumam piorar. Conclusão: Alimentos parecem influenciar o curso da Hidradenite Supurativa e estratégias nutricionais podem aliviar os sintomas.
Modelagem de distribuição de Moquiniastrum oligocephalum (Gardner) G. Sancho (Asteraceae: Gochnatieae) para a Bahia, Brasil
Authors: De Menezes Rebello Karoline , Santos de Almeida Gracineide Selma , Reis de Brito Gustavo
Published: August 2023

Moquiniastrum oligocephalum (Gardner) G. Sancho (Asteraceae: Gochnatieae), popularmente conhecida como candeia no Nordeste brasileiro, apresenta-se normalmente com hábito arbóreo, ginodióica, composta por capitulescências agrupadas em panículas reduzidas, axilares e pápus bisseriado. O estudo objetivou determinar a distribuição de M. oligocephalum para a Bahia, com base na modelagem da adequabilidade ambiental (MAA). A MAA pautou-se no recorte de condições climáticas (Worldclim), combinado a pontos de ocorrência georreferenciadas, obtidos nos bancos de dados do GBIF e SpeciesLink. A validação estatística dos modelos considerou AUC ≥ 0,7 e TSS ≥ 0,4 e os resultados AUC 0,97 e TSS 0,87. As variáveis que mais contribuíram foram: BIO1 - temperatura média anual (46.5%); BIO4 - sazonalidade da temperatura (44.9%). A modelagem mostrou maior adequabilidade para ambientes de caatinga, floresta tropical na porção norte, ao leste do estado, e baixa adequabilidade ambiental em áreas ao Sul e Oeste baiano. Assim, foi possível ampliar o conhecimento a cerca da distribuição da espécie e fornecer subsidios para as ações de conservação no estado da Bahia.
Oil spill in Ilha Grande Bay: analysis of the impact mitigation process
Authors: Correa-Silva Monica , Bastos Marcos , Mattos de Oliveira Ubirajara , Sant Anna Cortez Pedro , Zicari Amaral Marcella , Ferreira Magalhães Vanessa
Published: August 2023

In Brazilian waters, the main oil spills occurred near maritime terminals and oil refineries. In 2015, a leak spilled more than 25,000 liters of oil into the sea, during oil transfer operations between ships at the terminal's mooring pier. This event reached an area of 459 kilometers, between the bays of Ilha Grande and Sepetiba, with oil adhering to several coastal and island points. Impact assessments and mitigating measures were carried out during 3 months of daily technical monitoring in the field. Impact mitigation measures were agreed with the environmental inspection body, and low pressure washes, at room temperature with sea water, of shores with adhered oil, were carried out. Along the impacted area, several coastal points with populations of barnacles covered by oil were recorded, which subsequently showed high mortality rates. The washing of the points that had a large amount of adhered oil proved to be effective in cleaning the shores, and mainly in the release of substrate, for a new repopulation of organisms of the biological communities that occur in these ecosystems.
Level of Shooting Ability in Football Games at the Long Gathering Club, Padang Guci Hilir, Kaur Regency
Authors: Personi Megi , Anggara Deffri
Published: August 2023

This study aims to determine the ability to shoot in a soccer game at Padang Guci Hilir Long Gathering, Kaur Kaur District. This type of research is a qualitative descriptive research. The research sample is 25 people. The instrument used in this study was the Football shooting test. Where the results of the level of shooting ability in soccer games at the Padang Guci Hilir Gathering in Padang Guci Hilir Regency in this study show the classification of "good" to "very poor". Then where are the results of the final shooting ability test in the soccer game at the Padang Guci Hilir Long Gathering, Kaur Kaur Regency, as follows: that of the 25 players at the Padang Guci Hilir Gathering, Kaur Regency. As many as 3 people (12%) have very less category. As many as 5 people (20%) have less category. As many as 12 people (48%) have sufficient category. As many as 4 people (16%) have a good category and as many as 1 person (4%) have a very good category. Then it can be concluded that the Football Game Shooting Ability Test at the Padang Guci Hilir Club Arisan Panjang, Kaur Kaur Regency, is in the Enough category, namely 12 athletes or with a percentage of (48%).
Panorama de la diversidad lingüística en Colima
Authors: Caloca Michel Cecilia
Published: August 2023

Este texto invita al lector a entender los términos de diversidad cultural y lingüística a partir de recorrer su territorio, Colima, donde generaciones antiguas dejaron como herencias estos conceptos que continúan como protagónicos de nuestra historia en los siglos XX y XXI. Los colimenses siguen habitando cada rincón del terruño, entre el volcán y el mar, encontrándose desde la palabra, en diálogo con “el otro” y reconociéndose desde la diversidad.
Phytochemistry Analysis of Tiger Nut (Cyperus esculentus) Juice Fortified with Organic Additives
Authors: Ekperi R. E.
Published: August 2023

Plants’ juices are widely consumed due to their presumed high nutritional and medicinal qualities. This research evaluated the phytochemical properties of tiger nut (Cyperus esculentus) tuber juice/milk fortified with a mixture of ginger (Zingiber officinale) and Negro pepper (Xylopia aethiopica) extract. The freshly prepared tiger nut juice was fortified with 0%, 2%, 4% and 6% of the plants extracts, and accordingly coded TME 0, TME 1, TME 2 and TME 3; and their Phytochemical parameters measured through standard procedures. The findings indicated that the plants’ extract significantly increased, regardless of the phytochemical parameter investigated. The cardiac glycoside level in the juice fortified with 2%, 4% and 6% plants’ extract was 4.40%, 5.11% and 5.53% respectively; while the saponin content in the TME 0, TME 1, TME 2 and TME 3 juice samples was 6.68%, 6.82%, 7.40% and 7.70% respectively. Furthermore, it was observed that the anthocyanins and alkaloid levels in the juice increased from 3.12% - 3.93% and 5.13% - 7.34%, as the plants’ extract concentration increased from 0 to 6%. It was observed that the anti-nutrien compositions (phytate and tannin) of the tiger nut juice, increased in an uneven pattern as the fortification degree increased from 0% to 6%. This study’s findings will be useful in food industries in optimizing nutrient enhancement of foods and drinks, without accumulating excessive anti-nutrients in the fortified products.
Hobbes's Peace Dividend
Authors: Sorell Tom
Published: August 2023

Hobbes thinks that people who submit to government can not only hope for, but actually experience, something they recognize as a good life. The good life involves the exercise of harmless liberty—activity that the sovereign should not prohibit. The exchange of harmless liberty in the commonwealth for ruthless self-protection in the state of nature is what might be called Hobbes's peace dividend: the liberty of ordinary citizens to buy, sell, choose, and practice a trade as a source of income, and the liberty to keep some of the proceeds if the state does not need resources for public protection.
Nietzsche's Functional Disagreement with Stoicism: Eternal Recurrence, Ethical Naturalism, and Teleology
Authors: Mollison James
Published: August 2023

Several scholars align Nietzsche's philosophy with Stoicism because of their naturalist approaches to ethics and doctrines of eternal recurrence. Yet this alignment is difficult to reconcile with Nietzsche's criticisms of Stoicism's ethical ideal of living according to nature by dispassionately accepting fate—so much so that some conclude that Nietzsche's rebuke of Stoicism undermines his own philosophical project. I argue that affinities between Nietzsche and Stoicism belie deeper disagreement about teleology, which, in turn, yields different understandings of nature and human flourishing, so that Nietzsche's objections to Stoicism support his commitments to ethical naturalism and to affirming life's eternal recurrence.
Analysis of mathematical methods and principles of molecular dynamics and monte carlo method
Authors: Zhang Ruiqing
Published: August 2023

In this era, molecular dynamics and Monte Carlo methods have become the primary simulation methods. With the emergence of computer simulation research methods, it has been possible to solve the sizeable computational volume and some other problems in the simulation process. At present, molecular dynamics simulations have taken an essential place in the substantial computational system and have a remarkable ability to solve multi-body problems. Therefore, researchers widely use it in many fields such as physics, chemistry, and materials science. Meanwhile, the Monte Carlo method is also a very effective statistical simulation method. This method can far surpass ordinary integration in efficiency with guaranteed computational accuracy. Furthermore, the derived kinetic Monte Carlo method can simulate and study dynamics problems. It can be seen that both simulation methods play an vital role in various disciplines. Therefore, it is very significant to understand the mathematical principles behind them and to know their advantages and disadvantages.
The cracks of classical mechanics and the Birth of quantum mechanics
Authors: Lyu Yichen
Published: August 2023

At the end of the 19th century, with the development of Newton's classical mechanics and Maxwell's electromagnetism, a great number of individuals believed that the laws of physics had reached the point of perfection. Physicists like Pierre-Simon Laplace even thought that Newtonian mechanics could be used to calculate the future. However, the "dark clouds" such as the Michelson-Morley experiment and black body radiation demonstrated the flaws of the classical theory. With the efforts of quantum mechanics pioneers such as Planck, Einstein, Schrodinger, and Heisenberg, the discipline of quantum mechanics has gradually developed and has become the key to opening the door to the microscopic world. This paper demonstrates the cracks that occurred in classical physics at the end of the 19th century, and then illustrates the birth of the quantum mechanics and some of the most important concepts of it. Finally, some cutting-edge technologies related to quantum are introduced.
Analysis of the development status and future development trend of deep space network (DSN)
Authors: Ma Cheng
Published: August 2023

With the increase in the demand of space exploration in recent years and the increase in the amount of communication data between the earth and spacecrafts, the development of deep space communication is undoubtedly a great support for space exploration. Deep Space Network (DSN) is an important organization that helps people to get in touch with spacecrafts. This paper introduces the communication technology and achievements of the DSN and the problems that are still facing by it, and look forward to the future development trend of deep space communication and exploration technologies, so as to promote the development of Deep Space Network.
Band dispersion, velocity and effective mass of electrons in Kagome lattice
Authors: Zhou Yang
Published: August 2023

Kagome materials haven been one of the recent research hotspots, which cause many important phenomena such as ferromagnetism and superconductivity. The present study analyzes the electronic structure properties of Kagome materials, which reveals that the energy band structure is effectively regulated by the electron hopping term and that its flat band properties will disappear when the hopping terms cannot cancel each other. Meanwhile, it is also found that the effective mass and velocity of electrons are significantly dependent on the energy band structure. The results would help us better understand the properties of Kagome materials and contribute to their industrial applications.
The effect of aerodynamics on table tennis
Authors: Yang Qinghua
Published: August 2023

In the table tennis sport category, the different spin formula of table tennis ball will show different motion state, in which the important physical knowledge that is permeated aerodynamics. Besides the effect of aerodynamics, the balls can obtain different trajectories because of Magnus effect and Bernoulli principle. By using these three mainly professional knowledge, this paper analyzed the forces that the top-spin ball and back-spin ball acquired. What is more, the movement of side spin balls also be introduced through these professional knowledge. In addition to these analysis, 40mm and 38mm table tennis balls are compared in the paper. By using the principle of physical mechanics to reveal the secret and mechanism of the spin of table tennis ball, it provides a theoretical basis for improving the spin skill of table tennis ball.
Development of 5G NR RedCap devices
Authors: Wang Ruiyu
Published: August 2023

The subject of this paper is the RedCap technology. RedCap devices (known as Reduced Capability devices) are a new technology that is being studied by 3GPP in the R17 phase of 5G. RedCap can be defined as a lightweight version of 5G technology. The IoT application scenarios are extremely complex and diverse, and different scenarios have different requirements for network metrics. RedCap devices have emerged to fill the gap left by the withdrawal of 4G, i.e., to cover the needs of medium and high speeds. Specifically, it was designed to cover the needs of LTE Cat.1 and LTE Cat.4. Therefore, this article will introduce the reader to Release 17 RedCap devices by describing them from multiple perspectives, i.e. the history of RedCap devices, application scenarios, requirements, and their technical features. RedCap devices are well-balanced in their capabilities, using simpler demodulation (meaning significantly lower RF and baseband requirements), targeting bands with smaller spectrum bandwidths, and reducing the number of transceiver antennas and the number of MIMO layers. These changes have resulted in a reduction in the rate of RedCap devices, a reduction in coverage capability, and an increase in latency. Based on these changes, RedCap devices are expected to be 2-5 times less expensive than 5G. The main applications for RedCap are wearable devices (e.g. smart watches), industrial sensors and video surveillance devices.
An introduction to continuous functions, metric space, manifolds, topological spaces and its properties
Authors: He Wangzhe
Published: August 2023

A n-dimensional topological manifold is defined as an n-dimensional local Euclidean space M that is also a second countable space and a Hausdorff space. If a topological space has a countable base, it is referred to as a second countable space. At the same time, continuous function and metric space can help people to understand topological space better. This article will express some basic ideas about continuous functions, metric space, topological space and its properties, and topological manifolds. Moreover, the paper shows some basic ideas of how topological manifolds, topological space and function could be recognized and proved. Through analysis, this paper demonstrates the connection between them, such as using properties of continuous function to prove the definition and properties of topological manifolds and spaces.
Analysis on the working mode of electric propulsion system
Authors: An Xiangyu
Published: August 2023

At present, the electromagnetic propulsion technology and the electrostatic propulsion technology are more mature than before. With the increase of available power on the spacecraft, the performance can be better improved. This paper mainly reviews the electric propulsion technology for long-term space travel. It can be concluded that, compared to traditional chemical rocket systems, electric propulsion systems are more suitable for long-term space missions and have the ability to transport relatively heavy objects in space.
Analysis on the relation between the vertex angle of a tube airplane and its flying time
Authors: Xiao Boming
Published: August 2023

The tube is a type of airplane that is shaped as a hollow cylinder. In common sense, it seems impossible that an airplane has no wings, however, the tube airplane can fly even longer in the sky comparing with normal airplanes. In this paper, the practical experiment related to Bernoullis theorem and Magnus Force will be introduced. In order to understand those equations more deeply with logic, a paper airplane model called the tube is going to be studied. The author makes the models with different shapes and angles so as to figure out the relationship between the angle of the index and the flying time of the airplane. Results show that the angle of the index has an impact on the time of the airplane staying in the sky, and the angle affects the angular and linear rotating speed of the airplane so that the time required for the airplanes varies.
Simulation of SLM manufactured aluminum process and optimization of the parameters by computational fluid dynamics method
Authors: Gu Ye
Published: August 2023

The additive manufacturing technology of metal components is an advanced technology in the field of mechanical engineering and material science. Laser selective melting (SLM) is one of the most widely used methods in additive manufacturing. The temperature field of SLM process is the key factor to determine the quality of additive, so it has important research value. In this paper, the influence of laser power and additive speed on the temperature field of aluminum alloy additive manufacturing is studied by CFD numerical simulation technology. The results show that the CFD model can well simulate the SLM process. The additive temperature decreases with the increase of additive speed and increases with the increase of laser power. By adjusting the additive manufacturing parameters, the quality of additive manufacturing can be corrected and improved.
Discovering exoplanets in Pleiades with transiting exoplanet survey satellite
Authors: Huang Xinyue , Yan Yuhan , Yang Shuangyu , Yuan Meng
Published: August 2023

No transiting exoplanets have previously been found in the Pleiades. The Pleiades is a relatively young star cluster near us, which makes it valuable for investigation. This study aims to determine the existence of exoplanets in Pleiades using the transit method. Specifically, it sought to determine if the listed 83 stars have exoplanets by inspecting on light-curves from data of Transiting Exoplanet Survey Satellite (TESS). The TESS mission, with a better resolution and observed sky area than the previous Kepler mission, aimed to find more exoplanets around stars. To test the hypothesis that exoplanets do exist in the 83 stars of the Pleiades, we downloaded their light-curves using Jupyter notebook and the Lightkurve package, then checked using BLS method and fitting if there were transits. The results showed no clear sign of transiting planets in those stars. These results suggest that the 83 stars checked likely dont have a transiting exoplanet, but 83 stars cannot represent the whole Pleiades star cluster. Other methods should be used in analysis to gain more accurate results and more stars should be checked to investigate whether or not transiting exoplanets exist in the Pleiades star cluster.
The influence of the windshield shape of formula one racing car on the driver's head comfort
Authors: Wang Zirui
Published: August 2023

Since the actual use of the small windshield in Formula One (F1) cars is still unknown, the influence of the shape of the windshield edge on the driver's head will be the main research direction of this paper. In this paper, FLUENT is used to model three different shapes of windshield and the driver's head. The author analyzes the impact of windshield on the driver's head from the perspective of aerodynamics, speculates the actual use of different shapes of windshield, and gives some optimization schemes. Results show that the difference among the three shapes of windshield on the driver's head comfort is negligible, but the main role of the windshield is probably to create turbulence, allowing air to flow smoothly into the aerodynamic components at the rear of the car.
A study on electrical properties of silicon carbide power devices
Authors: Hu Xulin
Published: August 2023

Silicon Carbide (SiC) devices have the characteristics of high voltage resistance, fast switching speed, high working frequency, small on-resistance, and high-temperature resistance, and have broad application prospects in high voltage and high-power occasions. However, the application of SiC is faced with the problems of high-frequency switching transient voltage, current overshoot, ringing, and short circuit protection. Based on the problems encountered in the application process of SiC power devices, the characteristics and drive protection technology of sic devices are studied in this paper. In this paper, the static characteristic parameters of SiC device are studied, the switching characteristic parameters are tested, the influence of parasitic inductance parameters on the switching characteristic is analyzed, and the design method of PCB Roche coil is analyzed, the anti-interference performance of loop winding turns is analyzed and the driver protection circuit is designed.
Study of MLP-based classification of multi-cluster TPC signals
Authors: Liu Naiyuan , Shao Dehao , Tan Jiaqi , Wan Qianqian , Zhou Tianyu
Published: August 2023

This study focuses on the classification of multi-cluster events based on a parameterization of data from a time projection chamber using machine learning. Samples containing a mixture of single and overlapping two-cluster events, both in one and two dimensions, were studied using multi-layer perceptrons and other MVA algorithms provided in the Scikit-learn package. The classification was based on various sets of features and classification accuracies of up to 97% for 1D clusters and 97% for 2D clusters were obtained. This study demonstrates that the efficient classification of signals for further processing through machine learning is feasible and efficient.
Overview of high dimensional linear regression models
Authors: Li Jin
Published: August 2023

Linear regression analysis is one of the most basic and vital methods in statistical applications, especially when examining the relationship of one or more variables. This method initially used to analyze the relationship between father and child height has also been developed for nearly two hundred years. The development of computer technology has brought more efficient and accurate data processing, which allows us to use linear regression models to deal with high-dimensional and more complex scenarios. This paper mainly elaborates on the development of high-dimensional linear regression and the most classic models and tries to understand how some models can be improved. Finally, how to accurately apply model theory to practice will be a significant research direction in the future
An assumption of UWB enhancement of human motion recognition
Authors: Zhang Chenyuan
Published: August 2023

Today's VR games on the market use computers to connect a head-mounted monitor and two grips to build a virtual game world for players, providing players with a fresh sensory experience. However, the current VR game only uses the player's hand movement as a way of human-computer communication, the way is relatively single, and the player can not express their desire to play through only two hands, which cannot fully express the player's will. There are currently two types of motion capture used in consumer VR devices: optical capture, which is based on inertial sensor motion capture. These two are faced with the problem of extremely high cost and burden. The ultra-broadband system has the advantages of high positioning accuracy, low latency, cheap price, being light and portable, etc., which is very suitable for this kind of application scenario. This paper considers using two main technologies RTT ranging motion recognition and keyframe to achieve the aim.
Towards global recognition: Chinese recognition with non-local attention
Authors: Guo Yifan
Published: August 2023

As a part of image recognition, Chinese character recognition has a great application market in China, such as license plate recognition, logistics information recognition and so on. In recent years, the application of CNN has set off a frenzy of computer vision. Especially in the task of image recognition, CNN is widely used because of its high accuracy and few calculation parameters. However, CNNs local operation of using repeated filters to process images also has its shortcomings, for example, it cant pay attention to the relationship between distant pixels in the image. To solve this problem, we tried to add non-local operation to CNN to improve its performance. We chose the classic model of ResNetV2-50 as the foundation, and added non-local blocks to it. We compared the results of the two models and found that the accuracy increased by 4%.
Design and analysis of three types of stepper motor drive circuits
Authors: Chang Xinyi
Published: August 2023

Stepper motors work stably, are not affected by external factors, and errors do not accumulate. These advantages make them mostly used for open-loop control, so the control system is simple and is widely used in machinery, instrumentation, and automation fields. In this paper, three kinds of stepper motor driving circuits are designed based on the use of specific chip driving methods, using L297, L298 and ULN2003A driver chips, and AT89C51 microcontroller, respectively, and each circuit is introduced in detail in this paper. Each of these three circuits has different functions and requires different operation methods to achieve control of the stepper motor. By comparing the functions, application scope, and operation methods of the three circuits, it is concluded that the third driver circuit, which is composed of AT89C51 and ULN2003A, is widely used and convenient to use.
Research about how lead influence the detection rate of muons and its attenuation coefficient
Authors: Lyu Cefu , Hu Haojiang , Hu Chuyue , Wu Yifan
Published: August 2023

This paper presents a way to determine how lead influence the detection rate of muon at the earths surface. There are four sets of data on different thicknesses of lead above the detectors included in the experiments, and the largest set has 45054 groups of data. After using python modules to analyze the data of muons and other background particles such as electrons detected by desktop muon detectors, the discussion about identity of muons, especially about the detection rate, was conducted, as well as their relations with other factors. Then, the comparison was made between the average rate of muon detections of varied thicknesses of lead above the detectors to define the correlation between them. The result of data analysis mainly demonstrates an exponentially decreasing relationship. Accordingly, the calculation of the attenuation coefficient of lead which influences the exponential relationship was conducted as well.
Comparison of anti-interference ability between PID controller and ADRC controller in UAV operation at ocean
Authors: Xu Wanshun
Published: August 2023

With the maturity of UAV technology, drones can carry different instruments in the air to help people complete their work more efficiently. However, different working environments also bring different challenges to UAV control systems. This paper mainly discusses the quadrotor UVA and compares the stability of the Proportional Integral Derivative (PID) controller and Active disturbance rejection controller (ADRC) under the disturbance of gusts at sea. The flight principle of the quadrotor and the dynamic model of the quadrotor will be discussed on this basis. Then the composition and mathematical formula of the PID and ADRC controllers are introduced and compared. In general, this paper focused on the anti-jamming ability of different controllers under the influence of gust, which shows that although the ADRC controller has a more complex system and tedious parameter adjustment process in comparison with the PID controller, it has excellent anti-gust interference ability and can better serve the offshore operation of UAV.
Study on the aerodynamic performance of the racing car rear spoiler by CFD technology
Authors: Yang Leishuo
Published: August 2023

The rear spoiler is one of the main components that affect the aerodynamic performance of the F1 racing car. At present, numerical simulation technology is becoming a research hotspot to study the aerodynamic performance of the F1 racing car. In this paper, we discuss the F1 racing car rear spoiler airfoil selection and three-dimensional design and use three-dimensional simulation software to calculate the impact of different attack angles, velocity, and airfoils on the rear spoilers drag force and negative lift. The results show that the RAE2822 airfoil has a good lift-drag ratio at low velocity. When the attack angle is 30, the maximum lift-drag ratio can be obtained. When the velocity exceeds 60 m/s, the impact on the lift-drag ratio is almost negligible.
Research on the aerodynamic performance of the F1 racing car rear spoiler with different track characteristics
Authors: Zhang Chuwen
Published: August 2023

The rear spoiler of an F1 racing car is the main component that affects its aerodynamic performance. In the race, it is necessary to select the wing with different characteristics according to different track characteristics. In this paper, computational fluid dynamics (CFD) technology is used to study four different types of stationary airfoils, analyze their aerodynamic performance under three different track conditions, combine the characteristics of the track for quantitative analysis, and finally target the most suitable airfoil. Airfoil 2 is suitable for track 1 - Spa Francolchamp, a track with many curves and changeable climate, because of its medium negative lift value. The high negative lift force generated by airfoil 4 is applicable to the high altitude track, for example, Track 2 - The Rodriguez Brothers Track in this study. For airfoil 1, the lowest resistance value is applicable to track 3 - Silverstone, which is a track with many straight tracks and high-speed curves.
Comparison of the frontiers optical quantum communication technology with traditional classical communication technology
Authors: Zheng Yangyi
Published: August 2023

Due to the advancement of technology, laser communication, fiber optic communication and optical quantum communication have been developed, not only in the field of life, but also in the field of aviation, military and information security. This paper, mainly compares the difference between optical quantum communication and other communication technologies in terms of security and effectiveness, presenting the current state of technology and applications and providing an outlook on future directions. Through the comparison, this paper argues that the application of technology in optical quantum communication can promote the rapid development of quantum communication technology and thus enhance the comprehensive strength of global communication technology.
Determinism in hidden variable interpretation and Turings halting problem
Authors: Han Keyu
Published: August 2023

Heisenberg deduced the famous uncertainty principle which shows that there exist several conjugated quantities that can never be measured precisely at the same time. Further, Copenhagen interpretation gives a new perspective about quantum mechanics, which claims that particles do not have properties like position or momentum until people measure it. Hence, the famous EPR paradox was proposed to question the realism and locality of Quantum mechanics, which leads to the Hidden Variable explanation. However, this theorem was proved wrong by John Bell in 1964 with Bell Inequality. In addition, Hidden Variable Interpretation was developed by De Broglie and Bohm, they came up with the Bohmian Mechanics, which can be considered as Non-local Hidden Variable theorem. This interpretation gives physical meaning to waves. Unlike Copenhagen Interpretation, this theorem claims that particles do have a determined position. Some people may argue that it can be proved contradicted by using the Turing method (self-reference). Because if the algorithm represented by physics law described Hidden Mechanics to determine particles state, then the future is determined and predictable. Therefore, another algorithm can be established based on that, which will lead to Liar Paradox. This article will briefly introduce the uncertainty principle and some interpretations about quantum mechanics. Furthermore, this article will combine some ideas in Alan Turings Halting Problem to the universe of non-local hidden variables as a thought experiment, which involve self-reference, to give an interesting result of locality and determinism.
Research and performance analysis for the DWDM-QKD 5G fronthaul architecture
Authors: Wang Yifan
Published: August 2023

5G is another age of broadband portable correspondence innovation including high speed, low latency, and large connectivity, and quantum cryptography is a technology of the combination of quantum mechanics and cryptography. In order to combine 5G fronthual with the QKD (quantum key distribution), we conduct research on this paper. First, this paper proposes DWDM-QKD (dense wavelength division multiplexing-quantum key distribution) 5G fronthaul architecture. It contains AAU (active antenna unit) sites, multiplexer, de-multiplexer, and DU (distributed unit) sites. Second, the spontaneous Raman scattering noise interference model is analyzed theoretically, and the secure key rate calculation theory is used. Finally, the simulation evaluates the performance of QKD in the proposed architecture, the reduction of classical power can lead to an increase in the secure key rate.
Bilateral optimal denomination problem
Authors: Yin Xiangmiao
Published: August 2023

A common problem about currency denomination is the change-making problem. In this paper, a generalized denomination-related problem inspired by the optimal denomination problem is discussed, namely the bilateral optimal denomination problem. The solution maximizes a certain monetary value and thus can be applied in pricing strategies. Two key issues need to be addressed. One is how to properly formulate the problem in mathematical language. The other is how to compute the corresponding result with an algorithm. The paper learns from existing denomination algorithms and provides a solution to the problem from construction to implementation. Some limitations are needed to improve the practicality of the solution. An example of threshold discounts is used to illustrate the real-life application of the proposed problem.
Turbochargers and related technologies
Authors: Chen Jiahao
Published: August 2023

Turbochargers are one of the most important inventions to facilitate internal combustion engines. This paper is a thematic review of the technology of the turbocharger with emphasis on its workings, influencing factors, applications, problems, solutions and related or derived technologies for purposes outside the motoring industry. This paper reveals that the turbocharger resembles a modeled heat machine with thermodynamic processes for boosting engine power output with exhaust gas flow. It gives rise to various problems including inefficiencies, lags and conditions to be met, etc. As solutions, various mechanisms have been developed, as well as special modifications such as multiple turbochargers. E-boosting, gas turbines and microturbines have been discussed as related technologies with similarities in principles or origins that are of use in the power generation processes from various points of view, including principles, working conditions and efficiencies.
Review of research on performance of stirling engine regenerators
Authors: Bo Erjin
Published: August 2023

The performance of Stirling engine regenerators has a huge influence on the efficiency of Stirling engines. Hence, the Stirling engine design process focuses on the study of the engine regenerator. To find out possible ways to improve regenerator performance, scholars from different countries have done a lot of research on analytical methods and factors affecting heat flow in the regenerator. Whereas, different ways of modelling are used in these studies, and the results are not organized so well. The present work aims to summarize and arrange other researchers work and then provide evidence for practical improvements and optimization. In addition, this work clearly shows the aspects of regenerator analysis, which enables new researchers to better find their orientation.
Sound source signal location and tracking system based on STM32
Authors: He Xingcheng
Published: August 2023

With the progress of science and technology, sound source localization technology has a wide range of applications in urban traffic, digital hearing AIDS, mechanical systems and other fields, especially in noise monitoring and other aspects. In order to solve problems such as failure risk, this technology can accurately determine the location of the problem. At present, low-end manual technology is used in many fields, which is inefficient and a waste of time. Therefore, this paper designed a sound source signal positioning and tracking system based on STM32. The system takes STM32F407VET6 as the control core, and the speaker as the sound source that can emit self-defined regular sound. After the amplification circuits, it is sent to the microcontroller for processing.After sampling, the distance and offset Angle between the test point and the sound source are calculated by calculating the time deviation of the sound signal collected by the two microphones. Then control the steering gear rotation and laser alignment to realize the positioning and tracking of the sound source, and display the distance and offset information between the test point and the sound source in the terminal. With the development of modern technology, sound source localization can be widely used in daily life, and with the development of machine learning, cloud computing and electronic technology, this technology will have a broader application prospect.
Smart transit car design based on STM32 and OPENMV
Authors: Xu Chunkai
Published: August 2023

Under the background of the times, Smart Operating Vehicle has wide application prospects. This paper designs a Smart Car based on STM32F103RCT6 MCU, which combines the functions of OPENMV digital recognition module and infrared route tracing, in order to realize the function of the car to reach the designated location and start its operation. The scheme in this paper breaks the limitation of conventional manual work and can replace manual work in extreme environments such as high temperature and small space, which fully reflects the era significance of smart hardware.
Enhancing Virtual Teaching and Learning through Connectivism in University Classrooms
Authors: Omodan Bunmi Isaiah , Mtsi Nomxolisi , Mpiti Pretty Thandiswa
Published: August 2023

It is argued that teaching and learning in the 21st century rely heavily on technology, especially in university classrooms. This theoretical paper contends that for students to be successful in university classrooms in the 21st century, both lecturers and students should effectively resonate with technology. This paradigm shift is not without one or two challenges which must be addressed since teaching and learning through technology has come to stay. Therefore, this study presents the proponent of connectivism theory to enhance virtual teaching and learning in university classrooms. The study is located within a transformative worldview and derives its argument from a theoretical viewpoint by positioning connectivism as a tool to enhance teaching and learning in 21st-century university classrooms. Conceptual analysis was employed to argue the place of connectivism as a tool to enhance virtual classrooms in universities. The connectivism theory was presented, and its assumptions were argued in relation to how it could be integrated into university classrooms. The study concludes that the diversity of nodes' interconnections, coherence of things and adaptation to constant change are dimensions that could enhance virtual classrooms. Therefore, concerted efforts of both lecturers and students in universities to improve these dimensions to transform virtual space in university classrooms.
Envelope systems with high solar reflectance by the inclusion of nanoparticles – an overview of the EnReflect Project
Authors:   University of Porto, Ramos Nuno M M , Maia Joana ,   University of Porto, Veloso Rita Carvalho ,   University of Porto, Souza Andrea Resende ,   University of Porto, Dias Catarina ,   University of Porto, Ventura João ,   University of Porto
Published: August 2023

High reflectance materials constitute an attractive idea to reduce cooling loads, which is crucial for attaining the Nearly Zero Energy Buildings goal, also presenting the benefit of broadening the range of colours applicable in building facades. The EnReflect project intended to re-design envelope systems by increasing their solar reflectance through nanotechnology. The main idea was to produce novel nanomaterial-based coatings with high near-infrared (NIR) reflectance by tuning their optical properties and testing their compatibility with typical insulation technologies such as ETICS. As such, this project focused on the synthesis of nanoparticles with improved NIR reflectance, the evaluation of the hygrothermal-mechanical behaviour of thermal insulation systems with the application of the improved coating solutions, the characterization of the more relevant material properties and the durability assessment. One of the main achievements was the development of a facile synthesis of a nanocomposite with improved performance in the NIR region that allowed the reflectance improvement of a dark-finishing coating. Also, the incorporation of such nanoparticles had a positive effect on keeping their optical properties after accelerated ageing cycles. The development of numerical simulations allowed the estimation of the maximum surface temperature in Mediterranean climates under different optical parameters. The study of the hygrothermal behaviour of thermal enhanced façades led to the development of a new durability assessment methodology which contributed to closing a standardization gap.
Laboratory tests on decay of natural fibre insulation materials suggest a more differentiated evaluation and higher RH thresholds
Authors:   Fraunhofer Institute for Building Physics, Tanaka Eri , Schwerd Regina ,   Fraunhofer Institute for Building Physics, Hofbauer Wolfgang ,   Fraunhofer Institute for Building Physics, Zirkelbach Daniel ,   Fraunhofer Institute for Building Physics
Published: August 2023

To reduce CO2 emissions and save grey energy, natural materials like wood and wooden materials are becoming more and more important. However, these products are particularly sensitive to moisture, as they can be attacked by mould or decay fungi. In contrast to mould growth, which typically is associated with visual impairment and health problems, the growth of decay fungi may result in structural defects which clearly must be excluded. Up to now it is mostly assumed that wooden materials are more sensitive to such attack than solid wood. Therefore, different wood fibre insulation materials were inoculated with decay fungi and exposed to different climates to determine the requirements for the decay process and to compare them with the requirements of decay by the same fungi of solid wood. The results prove that some natural fibre materials are equally or even more resistant to decay fungi than solid wood, while others are less. The resistant products can therefore be assessed like solid wood – for which already temperature dependent thresholds and in part also transient decay prediction models are available. Maybe even specific higher moisture levels can be acceptable. However, the results also suggest a differentiated view on natural fibre insulations, as they have a very different susceptibility to wood decay. Uniform and significantly lower limits than for solid wood are not justified.
Water uptake measurement for thermal renovations – comparison between non-destructive method, the Karsten tube, and automatic laboratory measurements
Authors:   GWT TUD GmbH, Meißner Frank , Sonntag Heike ,   Technische Universität Dresden, Morandell-Meißner Anita ,   Technische Universität Dresden
Published: August 2023

The energy-efficient renovation of existing buildings requires precise knowledge of the wall structure. When using interior insulation systems, the driving rain resistance of the façade is also decisive for the function of the entire wall structure. When using interior insulation on exposed brick facades, the verification can often only be done with the help of a hygrothermal simulation. In practice, a non-destructive method, the Karsten tube or various modifications, is used to assess this essential characteristic value quickly. However, the measured values obtained from this method do not agree with the laboratory-measured values determined on a test specimen taken from the laboratory. This article presents measurements on bricks from several refurbishment projects to determine the cause. They were carried out both in the installed state with the in-situ method and subsequently after brick removal on the same materials under laboratory conditions to bring about comparability concerning the material. This article presents the automatic detection of water uptake of porous materials compared to the in-situ measurement with the Karsten tube. It evaluates the measurement results of both measurement methods.