bluuebunny/crossref_metadata_2025 huggingface dataset:
Reducing Ground Impact Hazards of a Solar UAV Through Modelling and Analysis
Authors: Dalla Vedova M D L , D’Amico F A , De Maria T , Maggiore P , Pitarresi G
Published: March 2024

The research described was conducted by a student team dedicated to finding sustainable and long-endurance systems and outlines an innovative solar panel UAV aircraft solution. Our prototype demonstrated the feasibility of the concept, while the second aircraft, currently in the design phase, aims to improve performance further and allow for extended self-powered flight time. The sustainable approach of our project addresses the growing need to reduce the environmental impact of transportation technologies. The main objective of this study is to address the requirements of the Specific Category - Civil Drones regulation, promulgated by EASA, regarding the risk associated with the impact of the aircraft on the ground in case of an in-flight failure. To address this issue, we conducted an in-depth analysis of possible failure scenarios and their consequences on the safety of the aircraft and people on the ground. Furthermore, the team developed models for risk assessment to evaluate the risk associated with solar panel UAV operation. To mitigate the risk of impact, we considered using a parachute, the effectiveness of which was analysed using a dynamic model implemented in Simulink. The analysis allowed us to evaluate the semi-controlled descent of the aircraft with the parachute attached, providing valuable information to optimize the safety system further. In conclusion, our study significantly contributes to ensuring the safety of our model in flight and on the ground through ground-impact risk management while promoting the development of sustainable and innovative solutions in the aviation field.
Preliminary design of an ATC support tool for the implementation of the Ad Hoc Separation Minima concept in an en-route sector.
Authors: Serrano-Mira Lidia , Sanz Luis Pérez , Pérez-Castán Javier A. , Mas-Sardá Juan Sánchez-Cano
Published: March 2024

The current aim in response to the anticipated growth in air traffic demand is to expand airspace capacity. However, this poses a challenge, as many airspace volumes are nearing saturation. An influential factor in determining airspace capacity is separation minima, which have remained unchanged for more than two decades. It seems that technological developments in recent years, such as new aircraft capabilities and ATC (Air Traffic Control) support tools, may eventually enhance current separation minima standards. Consequently, there is a push to improve separation management by introducing new operational concepts. Ad Hoc separation minima are one such concept, allowing different separation values to be applied within the same airspace volume based on factors such as aircraft models, weights, and wind conditions, among others. These values are computed individually for each aircraft pair in each situation. Implementing different separation minima values within the same airspace volume requires a significant change in certain ATC activities. In addition, new functionalities or ATC support tools are essential, as Air Traffic Control Officers (ATCO) cannot mentally determine the appropriate separation value for each situation. To address this, a new tool, the Ad Hoc Separation Minima Tool (ASMT), is proposed. It aims to integrate this concept seamlessly into an en-route (ENR) sector without increasing ATCOs workload and altering ATC responsibilities. This study provides a high-level overview of the ASMT architecture, and its functional system has been evaluated in a simulated ENR sector using MATLAB®.
Fuel consumption behaviour in aggregated air traffic metrics
Authors: Argerich Martín C , Álvarez Lorenzo R , Alonso G , Benito A
Published: March 2024

Currently there exist a wide variety of models that can be used to assess the fuel consumption of a single flight, from conventional models based on physics and flight performance to more innovative ones based on avant-garde techniques such as artificial intelligence. However, the quality of the fuel consumption estimated by these models usually relies strongly on the quality of data available. As consumed fuel is impacted by a wide variety of features, such as aircraft type, engine family, meteorological conditions, flight path, etc, the more information available, the more accurate the estimations will be.

However, having access to such granulated data is not always trivial and, moreover, the computational cost that could be derived from assembling data coming from different agents in the aviation field (airports, airlines, manufacturers, meteorological stations), plus the processing of the data and afterwards the computation of a refined fuel consumption model will be very high. The work presented here has been developed within the framework of the project E.R.A. (Environmentally Responsible Aviation) funded by Red.es, and it presents an extensive analysis on how consumed fuel and carbon dioxide emissions estimations could be made with limited access to information. Moreover, the aim is to be able to prove that for aggregated metrics, that being a set of flights and not a single flight, the consumed fuel can be easily estimated thus helping accounting for the carbon dioxide emissions that are produced at a global level.
Obsolescence in Aviation Systems of Systems with Applications in ATM
Authors: Pleter O T , Constantinescu C E
Published: March 2024

Systems-of-Systems theory is enlarging the perspective that engineers have on the objects of their work. Previously, efforts were focused at the system level, and by managing system inputs and outputs, all interactions between systems were thought to be addressed. With age, a system-of-systems designed individually at different moments in time will degrade as an overall fitness to purpose, will grow to a certain degree of obsolescence. In aviation this is most evident since systems invented and put in place 60 years ago are still operating. The assumptions made originally when the system was created became obsolete, gradually or in quantum leaps. This paper uses examples from air navigation to illustrate that the fitness for purpose for an individual system does change over time and with the changes in the environment the system is working in. The first time a system is established as an industry standard, its first design, and its first architecture presumably best fit the requirements, the specifications. Although these specifications of the system do not change in time, the fitness to the purpose does change and usually decays. This is only obvious in a systems-of-systems analysis, done for the system now part of a system-of-systems. The paper studies the following cases of obsolescence with impact on Air Traffic Management: Radar Altimeters, ILS Glide Slope intercept from above, Continuous Descent Approach effects on turbine engines, and evolution of SSR transponder utility.
Study on thermal conductivity of micron BN-nano SiO2 combined modified epoxy resin composites
Authors: Zhang Yiyi , Lan Danquan , Liu Peng , Feng Bo , Xu Danyang , Wu Min
Published: March 2024

Epoxy resin has attracted widespread attention in the field of power electronic packaging due to its favorable processing technology, high adhesion, and excellent dielectric properties. The enhancement of thermal conductivity in epoxy resin through the incorporation of diverse particles is a prominent area of interest in the realm of modified insulation materials. In this study, hexagonal boron nitride (h-BN) and silicon dioxide (SiO2) with good thermal conductivity were used as doped fillers to modify epoxy resin (EP). The analysis of experimental results indicated that the thermal conductivity of materials with a total doping amount of 20 wt% and a mass ratio of BN to SiO2 of 70:30 to 60:40 could increase the thermal conductivity by 118.1~126.0%. In contrast to pure EP, the thermal conductivity of composite epoxy resin materials has been significantly enhanced.
Comparative study on microstructure and hardness of P92 steel before and after long service
Authors: Fu Yangyang , Luan Gaocan , Zhao Pengfei , Ma Qinzheng , Zhu Baoyin , Xia Xianxi , Jin Xiao
Published: March 2024

Due to its exceptional mechanical properties, the P92 steel is extensively utilized in power plants for high-temperature and high-pressure components, such as main steam and reheated steam pipes. This study aims to characterize the microstructure and Brinell hardness of domestic and imported P92 steel before and after 50 kh of service under identical conditions using SEM (scanning electron microscope), EBSD (electron back scattering diffraction), TEM (transmission electron microscope), and a Brinell hardness tester. The findings reveal that the hardness of domestic P92 steel decreases from 222 HB to 200 HB after 50,000 hours (50 kh) of service, while the imported P92 steel experiences a slight decrease from 205 HB to 203 HB. During prolonged service, the martensitic lath broadening rate in domestic P92 steel surpasses that in imported P92 steel, which primarily accounts for the significant decline in hardness. Additionally, the presence of large-sized Laves phases at matrix lath boundaries, lath bundle boundaries, and grain boundaries in both domestic and imported P92 steels also contributes to the reduction in hardness.
Fluidization characteristics of iron ore powder in fluidized bed
Authors: Pang Jianming , Song Yaoxin , Li Shiwen , Yue Chongfeng , Zhao Zhimin , Luo Lingen
Published: March 2024

The fluidization characteristics of iron powder were studied on a self-made cold fluidized bed in the laboratory. The pressure distributed in the axial inside the lifting pipe of a fluidized bed gradually decreases to a constant value from underbody to roof. As the gas flow rate in the fluidized bed increases, the pressure on each axial section first increases and then decreases. When the inflation numbers are fixed, as the operating gas speed increases, the pressure on the same height segment decreases. When the operating gas speed of a fluidized bed is constant, the pressure increases with the increase of inflation numbers. The pressure at different bed heights is affected differently by the operating air speed: at the underbody of the bed, the pressure rapidly decreases with increasing operating airspeed. As the cross-sectional height increases, the influence of operating gas speed on pressure gradually decreases. As the charge increases, the pressure at the underbody of the fluidized bed rises rapidly, while the pressure at the roof changes gently. When iron ore fine powder is fluidized, distribution in axes of particle concentration shows an uneven distribution of upper dilute and lower dense. Under a certain loading number, increasing the operating airspeed will reduce the average concentration of granules in each axial section of the entire bed, and the particle concentration distribution in that section will become uniform. As the number of charges increases, the average concentration of granules in the riser increases, and the difference in particle concentration between the underbody and roof parts of the riser decreases.
Study on sinusoidal lapping micro-structured surface by abrasive stone with staggered abrasive particles
Authors: Liu Qi , Li Xingshan , Lyu Yushan , Hu Shenrong , Shang Zhaotong
Published: March 2024

In order to manufacture structured surfaces, firstly, the abrasive stone model with staggered abrasive particles is established with mathematical methods. Secondly, the motion of abrasive particles on the abrasive stone is designed. Finally, the surface morphology of the workpiece is simulated. The simulated workpiece morphology under different machining parameters is compared, and the influence of different machining parameters on the workpiece surface morphology is obtained. The results indicate that the microstructured surface can be lapped by using the abrasive stone of staggered abrasive particles. As the amplitude and frequency of the abrasive stone increase, the number of protrusions increases, and the area of individual protrusions decreases.
The microstructure and properties of high-strength structural steel for fruit auxiliary picking equipment
Authors: Feng Lulu , Yang Yanjun , Zhang Wenfeng , Qiao Weiwen , Tian Xuefeng
Published: March 2024

The microstructure and mechanical properties of high-strength structural steel used in the fruit-picking equipment were studied by using a metallographic microscope, a tensile tester, and an impact toughness tester. The results revealed that the structure of the experimental steels was a mixed microstructure of ferrite and pearlite, with an average grain size of ferrite of 12 μm. The yield strength was between 515-540 MPa and the tensile strength was 635-645 MPa. The impact toughness at room temperature reached over 200 J. The physical properties of the studied steels completely fulfilled the requirements of the high-strength structural steel for fruit auxiliary picking equipment. The new method cut down the tempering heat treatment process and decreased production costs.
Study on the effect of annealing rate on the impact resistance of the H-ZLaF50 vehicle plate glass
Authors: Jia Wentao , Liu Jiaxin , Wang Yaohong , Yao Guanpeng , Gao Xiaofang , Fang Xuezhou , Kou Xiaoyong , Xu Guangyi
Published: March 2024

The H-ZLaF50 glass has attracted much attention in the field of automotive glass applications due to its excellent mechanical properties. The effect of the annealing rate on the impact resistance of the H-ZLaF50 glass was studied. High-precision infrared stress meter was used to test the stress distribution of glass under different annealing rates and the influence of annealing rate on the stress distribution was found. Secondly, the impact resistance of the H-ZLaF50 glass samples was evaluated by the test method of electric falling ball impact resistance. The maximum impact energy of the H-ZLaF50 glass samples was 0.120 J. The results show that, compared with other annealing rates, the annealing rate of 1°C/min effectively improves the impact resistance of the H-ZLaF50 glass, which makes it more widely used in the automotive flat glass market.
Analysis and prevention of copper pipe corrosion
Authors: Xie Jinpeng , Teng Yulin , Zhang Li , Li Hui
Published: March 2024

The failure of the locomotive heat exchanger due to pitting and corrosion of the T2 heat exchange copper tube is used as the engineering application background. The pitting corrosion and influencing factors of T2 copper tu were studied by weight loss method, SEM, and EDS. The optimal ratio of compound corrosion inhibitors (borax, sodium nitrite, sodium silicate, and benzotriazol) of T2 copper tube was obtained. The results show that the main reason for the pitting corrosion of T2 copper pipe is the local rupture of cuprous oxide protective film on the copper surface, resulting in the copper at the bottom of the pit as the anode and the Cu2O oxide film on the surface as the cathode to form a corrosion cell so that copper dissolves and pitting in the pit. The rupture of the Cu2O oxide film is related to excessive carbon-containing residue and the deposition of dirt (foreign matter) on the surface, mechanical attack, and defects of the material itself. The optimal ratio of compound corrosion inhibitor in 2 L pure aqueous solution is as follows: Borax content is 4.4 g, sodium silicate content is 4.23 g, sodium nitrite content is 4 g, and benzotriazole content is 0.2 g.
Numerical simulation of air flow and distribution in the blast system of blast furnace
Authors: Xu Wenxuan , Qing Gele , Li Yanglong , Zhang Lijun , Yu Meng , Wang Fengqin
Published: March 2024

A three-dimensional geometric model of the blast system of the 5500 m3 blast furnace was established in this study. The velocity distribution of the blast system was calculated by OpenFOAM, and the velocity distribution at cross sections of the round pipe and the branch pipe was analysed. The main conclusions are as follows: (1) When the hot air enters the branch pipe, the air flow speed gradually increases and reaches its maximum value (approximately 266.7 m/s) at the tuyere outlet. (2) When the hot air enters the round pipe from the main pipe, there is momentum loss. When the hot air further reaches the opposite side of the junction between the round pipe and the main (Tuyere 1#), the speed of the hot air in the round pipe decreases to the minimum. (3) The maximum air flow average speed of the tuyere outlet is located at Tuyeres 20# and 21# at the junction of the main pipe and the round pipe, which can reach 264.5 m/s. The minimum air flow average velocity of the tuyere outlet is located at Tuyeres 19# and 22#, approximately 258.5 m/s.
Numerical simulation of spinning forming of A356 aluminum alloy hub using dual spinning rollers
Authors: Zhong Hao , Qu Shengguan , Long Wang , Deng Rixin , Zhou Wenxue
Published: March 2024

A finite element model of one-pass forming of an A356 aluminum alloy hub using dual spinning rollers was established, and the effectiveness of the finite element model was verified through experiment. The established finite element model was used to study the influence of the feed rate, the spindle speed, the axial distance of the two spinning rollers, and the friction coefficient on the forming quality of the hub. The result shows that a good forming quality could be obtained when the feed rate is 4 mm/s, the spindle speed is 220 rpm, the axial distance between the two spinning rollers is 3 mm or 7 mm, and the friction coefficient is 0.2. The simulation results can provide a reference for actual spinning production processes.
Real-time temperature monitoring and alarm system for biological samples storage based on FPGA
Authors: Li Chennong , Chen Yanxia , Zhong Xingping , Xu Youchun , Qin Lei
Published: March 2024

In the field of biosensing, high-quality biological samples are a prerequisite for precise analysis and detection. Strictly controlled storage temperature is crucial to ensure the stability of biological samples and achieve effective detection. Different biological samples require different temperature ranges for storage. Therefore, it is essential to design a temperature monitoring and alarm system capable of alarming based on different needs. This work presents a real-time temperature monitoring and alarm system based on the DS18B20 temperature sensor and FPGA chip. The system with simple structures has a wide temperature measurement range, an adjustable temperature alarm range, and a timely alarm function for various scenarios monitoring. This work demonstrates the temperature monitoring and alarm system for simple, accurate, and low-cost modes of temperature monitoring. The real-time temperature monitoring and alarm system will provide an effective means to strictly control the storage temperature of different biological samples, ensuring the stability and effectiveness of biological samples and the accuracy and sensitivity of biosensing and analysis.
Thermovision as a non – destructive method of technical condition assessment: case study in a smart building
Authors: Dębska L , Krawczyk N , Kapjor A
Published: March 2024

Currently, more and more emphasis is placed on building energy-efficient buildings from the highest quality materials to keep heat and energy losses as low as possible. Relatively, such buildings are much more expensive than traditional buildings due to the technology that is used in them. This applies to HVAC systems, renewable energy sources and etc. This paper presents the correctness of the thermal insulation of the Energis intelligent building at the Kielce University of Technology with the use of a thermal imaging camera. Measurements and photos were taken outside and inside the building, in the winter, in the late afternoon. This research topic was undertaken because few works and articles offer thermal imaging studies of smart buildings. The analysis of the thermograms showed differences between the surface of the windows and the walls from the inside, and additionally a place in the room in which you can see how cold is trying to penetrate the interior. The study provided data on thermal insulation of the tested building, its assessment and correctness of execution.
Study of water-side free cooling technology for power lithium battery plant
Authors: Lin Jiajing
Published: March 2024

Power lithium battery production process needs to consume a lot of energy. In this paper, an energy consumption analysis of a representative company was conducted, the energy consumption of the facilities that provide support for the process is higher than the energy consumption of the process equipment itself, which greatly affects the cost of battery manufacturing. Air-conditioning system as the most important energy-consuming system of the facilities, accounting for 25% to 45% of the total electricity consumption. The energy consumption of the cooling source system dominates, even in winter its energy consumption can reach 14% of the total energy consumption. On this basis, this paper analyzes the chilled-water-use characteristics of the air-conditioning terminal in winter through theoretical analysis, the chilled water temperature is therefore optimized according to the real-time outdoor humidity. The chilled water temperature is linearly increased after the humidity ratio fall below 7.5g/kg(a), reaching a maximum value of 12.1°C at 6g/kg(a). In addition, the cooling tower free cooling technology based on the optimized chilled water temperature is innovatively proposed to fully explore the energy-saving potential of the technology to achieve the energy saving of the cooling source system. TRNSYS simulation results show that after optimizing the chilled water temperature, the time period for cooling tower individual cooling under winter operating condition is extended by 60%, and cooling source system energy saving rate can reach 49.0% and the cost saving rate 48.0%, both of which are higher than 15% compared to the un-optimized chilled water temperature.
Pilot project on “green” hydrogen generation at the territory of Turkmenistan
Authors: Jumayev A.Ya.
Published: March 2024

This paper recommends the production of the “green” hydrogen at the territory of Turkmenistan. The electrical energy required for the production of “green” hydrogen is generated by a photovoltaic solar station. Current work presents a modelling project, which consists of electric power source – photovoltaic solar station (PVS) with a capacity of 100 MW, system of generation of hydrogen (electrolyzer with a capacity 50 MW) and the system of freshening – installation of the reverse osmosis with an output of 80 tons water a day.
Design and preliminary test results of the charge sensitive amplifier for gain-less charge readout in high-pressure TPC
Authors: Yang Y. , Liang T. , Gao C. , Zhang D. , Chen K. , Wang H. , Liu J. , Liu L. , Qiao Y. , Hu Z. , Sun X. , Tian X. , Song Z. , Huang G.
Published: March 2024

This paper presents the design and electrical test results of a low-noise front-end chip (named Topmetal-S) in a High-pressure Time Projection Chamber (TPC) for searching the neutrinoless double beta decay. The Topmetal-S has been fabricated in a 130 nm CMOS technology. The proposed front-end chip consists of a charge collection electrode, a Charge Sensitive Amplifier (CSA) and peripheral circuits. The test results indicate that the CSA features an input linear dynamic range of approximately 6.64 fC, a charge-conversion gain of about 220 mV/fC and an Equivalent Noise Charge (ENC) of approximately 115 e
- after a digital trapezoidal pulse shaper.
The OBDT-theta board: time digitization for the theta view of Drift Tubes chambers.
Authors: Sastre J. , Bedoya C.F. , Cuadrado S. , Cuchillo J. , Francia D. , de Lara C. , Navarro A. , Paz R. , Redondo I. , Redondo D. ,   the CMS Muon group
Published: March 2024

We present the design and performance of the On-Board electronics for the Drift Tubes (OBDT) for the superlayer theta along the direction parallel to the beam-line, the new board built to substitute part of the CMS DT Muon on-detector electronics. The OBDT-theta is responsible for the time digitization of the DT chamber signals for the theta view, allowing further tracking and triggering of the barrel muons. It is also in charge of part of the slow-control of the DT chamber inner electronics in the theta view. Prototypes of the OBDT-theta board are under validation in different laboratories in CERN, as well as in demonstrator chambers installed in the CMS experiment. This allows evaluation of the full functionality of the boards in real conditions, showing very satisfactory results.
Plasma-assisted pyrolysis for converting oil palm fronds into reduced graphite oxide
Authors: Purawiardi R I , Dimyati A , Handayani A H , Kismanto A , Sari Y W , Maddu A , Elbersen H W
Published: March 2024

One of the oil palm tree’s solid waste is oil palm fronds. Due to its lignocellulosic composition, it has the potency to convert it into carbon. The common heat treatment method to convert oil palm fronds into carbon-based material is pyrolysis. However, this process has some disadvantages, such as being time-consuming and just producing amorphous carbon. Different from common pyrolysis temperatures, in this study we use a higher temperature (4000 °C) generated by DC current arc plasma. This process is faster than the common pyrolysis process (less than 10 minutes) and produces crystalline material. This product is then characterized by Raman spectroscopy, SAED-TEM, XRD, FT-IR, and SEM/EDX. Based on Raman spectroscopy, this crystalline material shows the characteristics of semiconductor carbon. Based on the SAED-TEM, there is a (002) plane of hexagonal crystal structure detected (graphite phase characteristics). An XRD analysis shows the characteristics of the trigonal crystal structure (P3) constructed by O and H atoms. An FT-IR characterization shows that there are C=C, C-H, and O-H bonds, while the EDX analysis result shows a carbon-to-oxygen ratio of about 4.23. Therefore, based on the whole interpretation, the plasma-assisted pyrolysis treatment is successfully used to convert oil palm fronds into reduced graphite oxide (rGO).
Fault-tolerant fusing of repeater graph states and its application
Authors: Xu Shuang , Gong Wei-Jiang , Shen H Z , Yi X X
Published: March 2024

A repeater graph state (RGS) is a class of multipartite entangled states with favourable features for quantum communication, particularly as the enabler of all-photonic quantum repeaters. In this paper, based on an alternative formalism, we show that two RGSs can be fused via a Bell measurement in a fault-tolerant manner. The fusing of multiple RGSs can thus be carried out simultaneously and flexibly, which enables a 2-step rapid generation of an arbitrarily large RGS from relatively small building blocks using heralded but non-deterministic photonic Bell measurements. It then makes possible the distribution of a large multipartite entangled state from multiple sources to many parties via high-loss channels, and hence also a satellite-based entanglement distribution scheme. In such a scheme, stationary memories are only required for ground stations, the growth of memory noise with its scale can be effectively suppressed, and recipients of entangled pairs of qubits may remain anonymous.
Influence of temperature perturbation on moisture dynamics
Authors: Abawari Admasu , Elfaged Yitagesu
Published: March 2024

We analyzed the perturbation effect of temperature on the moisture content in the atmosphere [1], considering the saturation phenomenon. The air parcels of a saturated atmosphere are made of dry air, vapor, cloud, and rain water that flow on a rotating Earth, with a temperature perturbations induced at

9
°

1

′

48

″

N,

38
°

44

′

24

″

E

and 6.324 km above the Earth’s surface. The fundamental atmospheric parameter of this saturated moist air was treated as temperature-dependent, and the pressure force exerted on it by the precipitation and cloud water is not considered in the numerical computation. In this proposed research, the initial value of wind speed along zonal, meridional, and vertical directions varies with elevation, and the interaction of the atmosphere with the Earth’s surface is not neglected. The result of the investigation revealed that a single tropospheric disturbance of an atmospheric variable is a major factor in the spread of different long period waves patterns (350 hours) and this atmospheric oscillations play a crucial role in transferring energy, momentum, and mass across different parts of the atmosphere, impacting global climate systems.
Assessing rainfall erosivity changes over China through a Bayesian averaged ensemble of high-resolution climate models
Authors: Weng Xuerou , Zhu Jinxin , Wang Dagang , Zhong Ming , Luo Ming , Mei Yiwen , Tang Guoping
Published: March 2024

Spatiotemporal variation in rainfall erosivity resulting from changes in rainfall characteristics due to climate change has implications for soil erosion in developing countries. To promote soil and water conservation planning, it is essential to understand past and future changes in rainfall erosivity and their implications on a national scale. In this study, we present an approach that uses a Bayesian model averaging (BMA) method to merge multiple regional climate models (RCMs), thereby improving the reliability of climate-induced rainfall erosivity projections. Our multi-climate model and multi-emission scenario approach utilize five RCMs and two Representative Concentration Pathways (RCP4.5 and RCP8.5) scenarios for the baseline period (1986–2005) and future periods (2071–2090) to characterize the spatiotemporal projection of rainfall erosivity and assess variations in China. Our results indicate that the two models outperform other models in reproducing the spatial distribution and annual cycle of rainfall erosivity in China. Moreover, we found an increasing trend in the annual rainfall erosivity from the baseline climate up to the RCMs for all models, with an average change in erosivity of approximately 10.9% and 14.6% under RCP4.5 and RCP8.5, respectively. Our BMA results showed an increase in the absolute value of rainfall erosivity by 463.3 and 677.0 MJ·mm·hm−2·h−1, respectively, in the South China red soil region and the Southwest China karst region under the RCP8.5 scenario. This increase indicates that climate warming will significantly enhance the potential erosion capacity of rainfall in these regions. Additionally, our study revealed that the Southwest China karst region and the Northwest China Loess Plateau region are more sensitive to radiation forcing. To mitigate the risk of soil erosion caused by climate change, it is necessary to consider changes in rainfall erosivity, local soil conditions, vegetation coverage, and other factors in different regions and take appropriate soil and water conservation measures.
Efficient concentration of trace analyte with ordered hotspot construction for a robust and sensitive SERS platform
Authors: Hu Youdi , Hu Yanlei , Wang Zhenyu , Yong Jiale , Xiong Wei , Wu Dong , Xu Shixiang
Published: March 2024

Surface-enhanced Raman scattering (SERS) platform, which enables trace analyte detection, has important application prospects. By structuring/modifying the surface of the SERS substrate, analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive detection. However, subject to the difficulty of the fabrication process, it remains challenging to balance hot-spot construction and the concentration capacity of analyte simultaneously. Therefore, preparing SERS substrates with densely ordered hot spots and efficient concentration capacity is of great significance for highly sensitive detection. Herein, we propose an Ag and fluoroalkyl-modified hierarchical armour substrate (Ag/F-HA), which has a double-layer stacking design to combine analyte concentration with hotspot construction. The microarmour structure is fabricated by femtosecond-laser processing to serve as a superhydrophobic and low-adhesive surface to concentrate analyte, while the anodic aluminium oxide (AAO) template creates a nanopillar array serving as dense and ordered hot spots. Under the synergistic action of hot spots and analyte concentration, Ag/F-HA achieves a detection limit down to 10−7 M doxorubicin (DOX) molecules with a RSD of 7.69%. Additionally, Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or abrasion. Based on our strategy, SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with defects. This work opens a way to the realistic implementation of SERS in diverse scenarios.
Piezotronic neuromorphic devices: principle, manufacture, and applications
Authors: Lin Xiangde , Feng Zhenyu , Xiong Yao , Sun Wenwen , Yao Wanchen , Wei Yichen , Wang Zhong Lin , Sun Qijun
Published: March 2024

Highlights

The operating mechanism of piezotronic neuromorphic devices and related manufacturing techniques are presented.

Recent research advances in piezotronic neuromorphic devices including multifunctional applications are summarized.

Challenges and prospects for modulating novel neuromorphic devices with piezotronic effects are discussed.
A novel three-dimensional orthogonal star honeycomb structure with negative Poisson’s ratio
Authors: He Baofeng , Huang Qian , Shi Zhaoyao
Published: March 2024

A novel three-dimensional(3D) orthogonal star honeycomb structure with increased strength and negative Poisson’s ratio(NPR) performance that is not subject to angle constraints was proposed, and the calculation model of Young’s modulus and Poisson’s ratio of the cell structure under axial load was derived in this study. Through the investigation of the deformation mode and the finite element (FE) research results of the structure, it is found that the longitudinal length parameter

l

2

and angle parameter

θ

2

are important concave axes that affect the mechanical properties of materials. The quasi-static compression experimental results shows that the constraints of adjacent elements can enhance the strength of the structure to a certain extent, and the theoretical analysis results and the FE simulation results were in good agreement with the experimental results. In addition, the results are also concluded that the prediction of Young’s modulus and Poisson’s ratio and the designability of mechanical properties of 3D orthogonal star honeycomb structures could be achieved by the theoretical calculation formula derived in this study.
Optimizing bearing health condition monitoring: exploring correlation feature selection algorithm
Authors: Sharma Anju , Priya Taruv Harshita , Naidu VPS
Published: March 2024

Vibration signals are a critical source of information for detecting and diagnosing bearing faults, making this research particularly relevant to the condition monitoring of industrial machinery, particularly bearings using vibration signals. This study delves into how feature selection can be done using Pearson’s Correlation Co-efficient within the context of monitoring bearing health conditions, utilizing two distinct approaches. Approach-1 involves feature selection without considering labels, while Approach-2 incorporates labels for feature selection. Comparative analysis is conducted against outcomes obtained when all features are selected. The research scrutinizes the impact of feature selection on classifier performance, accuracy, and execution times, utilizing various machine learning algorithms such as Decision Tree (DT), K Nearest Neighbor (KNN), Support Vector Machine (SVM), and Naïve Bayes (NB). The findings underscore that feature selection significantly enhances classifier accuracy while reducing execution times. Specifically, only DT and KNN with 50 neighbors achieved 100% accuracy when all features were considered. However, with feature selection using Approach-1 (without labels), DT, KNN, SVM (excluding 100 neighbors), and NB (with Normal/Gaussian kernel) attained 100% accuracy. Employing Approach-2 (with labeled features), DT with 0.7 and 0.9 thresholds, SVM-G with all thresholds (0.6, 0.7, and 0.9), KNN with all thresholds (except 100 neighbors), and NB-n (with all thresholds) achieved 100% accuracy. The study emphasizes the pivotal role of feature selection using Pearson’s Correlation Coefficient in enhancing machine learning classifier performance, offering promising avenues for future research and practical applications across diverse domains.
Finite element approximation for uniformly elliptic linear PDE of second order in nondivergence form
Authors: Tran Ngoc Tien
Published: March 2024

This paper proposes a novel technique for the approximation of strong solutions

u
∈
C
(

Ω
¯

)
∩

W

l
o
c

2
,
n

(
Ω
)

u \in C(\overline {\Omega }) \cap W^{2,n}_\mathrm {loc}(\Omega )

to uniformly elliptic linear PDE of second order in nondivergence form with continuous leading coefficient in nonsmooth domains by finite element methods (FEM). These solutions satisfy the Alexandrov-Bakelman-Pucci (ABP) maximum principle, which provides an a posteriori error control for

C
1

C^1

conforming approximations. By minimizing this residual, we obtain an approximation to the solution

u
u

in the

L
∞

L^\infty

norm. Although discontinuous functions do not satisfy the ABP maximum principle, this approach extends to nonconforming FEM as well thanks to well-established enrichment operators. Convergence of the proposed FEM is established for uniform mesh-refinements. The built-in a posteriori error control (even for inexact solve) can be utilized in adaptive computations for the approximation of singular solutions, which performs superiorly in the numerical benchmarks in comparison to the uniform mesh-refining algorithm.
Loss
Authors: Deaves Richard
Published: March 2024

This chapter focuses on behavioral risk preference as formulated by prospect theory. The prospect theory utility function is based on changes in wealth (rather than levels). Another key innovation is its incorporation of loss aversion, which means that the pain of a loss is more impactful than the pleasure of a gain of the same magnitude. Additional needed refinements are decision weights based on transformed probabilities, the calculation of the utility of a prospect, integration vs. segregation, and rank-dependent utility. Determinants of risk preference coming from psychological tendencies are also described, with one notable finding being that affect-rich environments lead to greater departures from expected utility theory.
Performers
Authors: Deaves Richard
Published: March 2024

This chapter focuses on the investment performance of individual investors. If someone has the right skill set, there is nothing wrong with the pursuit of active investment management. Unfortunately, reality is otherwise for most investors. The evidence makes clear that on average their performance is very much wanting at the level of the portfolio. This seems to stem in large part from excessive trading induced by overconfidence. Overconfidence operates by making people think they know more than actually do know, leading them to discount the consensus view of other investors inherent in market prices. Another problem well documented at the level of the portfolio is insufficient diversification.
Lambda3: homology search for protein, nucleotide, and bisulfite-converted sequences
Authors: Hauswedell Hannes , Hetzel Sara , Gottlieb Simon G , Kretzmer Helene , Meissner Alexander , Reinert Knut
Published: March 2024

Motivation

Local alignments of query sequences in large databases represent a core part of metagenomic studies and facilitate homology search. Following the development of NCBI Blast, many applications aimed to provide faster and equally sensitive local alignment frameworks. Most applications focus on protein alignments, while only few also facilitate DNA-based searches. None of the established programs allow searching DNA sequences from bisulfite sequencing experiments commonly used for DNA methylation profiling, for which specific alignment strategies need to be implemented.

Results

Here, we introduce Lambda3, a new version of the local alignment application Lambda. Lambda3 is the first solution that enables the search of protein, nucleotide as well as bisulfite-converted nucleotide query sequences. Its protein mode achieves comparable performance to that of the highly optimized protein alignment application Diamond, while the nucleotide mode consistently outperforms established local nucleotide aligners. Combined, Lambda3 presents a universal local alignment framework that enables fast and sensitive homology searches for a wide range of use-cases.

Availability and implementation

Lambda3 is free and open-source software publicly available at https://github.com/seqan/lambda/.
A similarity-based assortativity measure for complex networks
Authors: Fierens Pablo I , Chaves Rêgo Leandro
Published: March 2024

There are several metrics that have been proposed to quantify the tendency of nodes to link with similar nodes in complex networks. Among them, the assortativity coefficient put forth by M.E.J. Newman has been successfully used in many cases with either categorical or scalar attributes of network nodes. Unfortunately, the assortativity coefficient cannot deal with vectorial attributes. Furthermore, we show that, in certain cases, it may not be able to capture the similarity of neighbors. In this work, we introduce a new metric that, without being much more complex to calculate, solves those problems. Moreover, we show that the proposed metric includes the categorical assortativity coefficient as a particular case. We also study the behavior of the new metric with a few illustrative real-world examples.
Toward Patient Centricity: Why Do Patients With Inflammatory Bowel Disease Participate in Pharmaceutical Clinical Trials? A Mixed-Methods Exploration of Study Participants
Authors: Solitano Virginia , Prins Heather , Archer Meagan , Guizzetti Leonardo , Jairath Vipul
Published: March 2024

Background

A better understanding of motivations to participate as well as recommendations to reduce barriers to enrollment may assist in design of future clinical trials.

Methods

We developed a 32-item electronic questionnaire to explore motivations, experiences, and recommendations of inflammatory bowel disease patients, who had participated in pharmaceutical clinical trials in a tertiary center in Canada over the last decade. We employed a mixed-methods approach that integrates both quantitative and qualitative research methods.

Results

We distributed a total of 69 e-mails with surveys and received 46 responses (66.6% response rate). Study participants were mostly male (27/46, 58.7%), non-Hispanic White (43/46, 93.5%), with a mean age of 45.5 years (SD 10.9). Most decided to participate in a clinical trial to benefit future patients (29/46, 63.0%). Half of the participants (23/46, 50.0%) reported they were worried about the possibility of receiving placebo, although the majority (29/46, 63.0%) understood they could improve on placebo. The most challenging aspect reported was the number and length of questionnaires (15/46, 32.6%), as well as the number of colonoscopies (14/46, 30.4%). Strategies recommended to increase enrollment were reduction of the chance of receiving placebo (20/46, 43.5%), facilitating inclusion of patients who have failed multiple therapies (20/46, 43.5%), allowing virtual visits (18/46, 39.1%), including subtypes of disease traditionally excluded from trials (16/46, 34.8%) and improving outreach to underrepresented populations (13/46, 28.3%). The vast majority (37/46, 80.4%) reported their experience of participation to be better than expected.

Conclusions

These results should help inform the design of future clinical trials with a focus on patient-centricity.
Breaking the Narrative Pattern: Motherhood Tropes in Norwegian Migrant Literature
Authors: Barkve Marit Ann
Published: March 2024

This article focuses on three motherhood tropes, which became narrative convention in Norwegian migration literature in the period 1986–2010. I categorize these motherhood tropes as: (1) the cultured mother; (2) the creative mother; and (3) the appropriation of Henrik Ibsen’s infamous character Nora Helmer. Illustrating these tropes shows a critique of motherhood found in some of Norway’s migration literature. However, Mala Naveen’s novel, Desiland (Desi Land), published in 2010, incorporates and challenges these three motherhood tropes by breaking with convention. I argue that Naveen performs disidentification, or an identity in difference, and calls for a renegotiation or remapping of the current paradigm of Norwegian migration literature, which limits minority women’s artistic representation.
Machine learning–based analysis of non-invasive measurements for predicting intracardiac pressures
Authors: van Ravensberg Annemiek E , Scholte Niels T B , Omar Khader Aaram , Brugts Jasper J , Bruining Nico , van der Boon Robert M A
Published: March 2024

Aims

Early detection of congestion has demonstrated to improve outcomes in heart failure (HF) patients. However, there is limited access to invasively haemodynamic parameters to guide treatment. This study aims to develop a model to estimate the invasively measured pulmonary capillary wedge pressure (PCWP) using non-invasive measurements with both traditional statistics and machine learning (ML) techniques.

Methods and results

The study involved patients undergoing right-sided heart catheterization at Erasmus MC, Rotterdam, from 2017 to 2022. Invasively measured PCWP served as outcomes. Model features included non-invasive measurements of arterial blood pressure, saturation, heart rate (variability), weight, and temperature. Various traditional and ML techniques were used, and performance was assessed using R2 and area under the curve (AUC) for regression and classification models, respectively. A total of 853 procedures were included, of which 31% had HF as primary diagnosis and 49% had a PCWP of 12 mmHg or higher. The mean age of the cohort was 59 ± 14 years, and 52% were male. The heart rate variability had the highest correlation with the PCWP with a correlation of 0.16. All the regression models resulted in low R2 values of up to 0.04, and the classification models resulted in AUC values of up to 0.59.

Conclusion

In this study, non-invasive methods, both traditional and ML-based, showed limited correlation to PCWP. This highlights the weak correlation between traditional HF monitoring and haemodynamic parameters, also emphasizing the limitations of single non-invasive measurements. Future research should explore trend analysis and additional features to improve non-invasive haemodynamic monitoring, as there is a clear demand for further advancements in this field.