bluuebunny/crossref_metadata_2025 huggingface dataset:
Calibrated Photoacoustic Spectrometer Based on a Conventional Imaging System for In Vitro Characterization of Contrast Agents
Authors: Lucas Théotim , Sarkar Mitradeep , Atlas Yoann , Linger Clément , Renault Gilles , Gazeau Florence , Gateau Jérôme
Published: August 2022

Photoacoustic (PA) imaging systems are spreading in the biomedical community, and the development of new PA contrast agents is an active area of research. However, PA contrast agents are usually characterized with spectrophotometry or uncalibrated PA imaging systems, leading to partial assessment of their PA efficiency. To enable quantitative PA spectroscopy of contrast agents in vitro with conventional PA imaging systems, we have developed an adapted calibration method. Contrast agents in solution are injected in a dedicated non-scattering tube phantom imaged at different optical wavelengths. The calibration method uses a reference solution of cupric sulfate to simultaneously correct for the spectral energy distribution of excitation light at the tube location and perform a conversion of the tube amplitude in the image from arbitrary to spectroscopic units. The method does not require any precise alignment and provides quantitative PA spectra, even with non-uniform illumination and ultrasound sensitivity. It was implemented on a conventional imaging setup based on a tunable laser operating between 680 nm and 980 nm and a 5 MHz clinical ultrasound array. We demonstrated robust calibrated PA spectroscopy with sample volumes as low as 15 μL of known chromophores and commonly used contrast agents. The validated method will be an essential and accessible tool for the development of new and efficient PA contrast agents by improving their quantitative characterization.
Fiber Bragg Grating Array for Shape Reconstruction in Structural Elements
Authors: Souza Edson A. , Macedo Leandro C. , Frizera Anselmo , Marques Carlos , Leal-Junior Arnaldo
Published: August 2022

This paper presents the development, analysis and application of a fiber Bragg grating (FBG) array for two-dimensional (2D) shape reconstruction in a cantilever beam. The structural elements made of Pinus wood and Nylon 6.0 were numerically analyzed using the finite element method for the strain distribution when constant loading is applied at the free end of the beam. In addition, the temperature compensation method is proposed to decouple the temperature cross-sensitivity in the deflection analysis. In this case, the temperature sensitivities of all sensing elements of the 5-FBG array were obtained. An additional FBG was encapsulated in a silicone mold for increased sensitivity and positioned in the clamping point in which deflection was negligible. Temperature compensation was achieved considering the temperature measured by the silicone-embedded FBG (sensitivity of 27.78 pm/°C) and the sensitivity of all five FBGs of the deflection-sensing array (9.14 pm/°C ± 0.33 pm/°C). In the deflection experiments, the sensors presented a high linearity, in which a determination coefficient (R2) higher than 0.995 was obtained in all of the analyzed cases. Furthermore, the 2D shape construction using the proposed sensor approach resulted in the elastic line estimation for all analyzed beams, where the experimental results were in agreement with the theoretical and numerical analysis with a R2 higher than 0.99 in all of the analyzed cases. Therefore, the proposed sensor array is a feasible approach for real-time shape reconstruction of structural elements with the advantages related to the possibility of direct embedment in the measured structure.
DL-Based Physical Tamper Attack Detection in OFDM Systems with Multiple Receiver Antennas: A Performance–Complexity Trade-Off
Authors: Dehmollaian Eshagh , Etzlinger Bernhard , Torres Núria Ballber , Springer Andreas
Published: August 2022

This paper proposes two deep-learning (DL)-based approaches to a physical tamper attack detection problem in orthogonal frequency division multiplexing (OFDM) systems with multiple receiver antennas based on channel state information (CSI) estimates. The physical tamper attack is considered as the unwanted change of antenna orientation at the transmitter or receiver. Approaching the tamper attack scenario as a semi-supervised anomaly detection problem, the algorithms are trained solely based on tamper-attack-free measurements, while operating in general scenarios that may include physical tamper attacks. Two major challenges in the algorithm design are environmental changes, e.g., moving persons, that are not due to an attack and evaluating the trade-off between detection performance and complexity. Our experimental results from two different environments, comprising an office and a hall, show the proper detection performances of the proposed methods with different complexity levels. The optimal proposed method achieves a 93.32% true positive rate and a 10% false positive rate with a suitable level of complexity.
Wavelet-Domain Information-Hiding Technology with High-Quality Audio Signals on MEMS Sensors
Authors: Zhao Ming , Chen Shuo-Tsung , Tu Shu-Yi
Published: August 2022

Due to the rapid development of sensor technology and the popularity of the Internet, not only has the amount of digital information transmission skyrocketed, but also its acquisition and dissemination has become easier. The study mainly investigates audio security issues with data compression for private data transmission on the Internet or MEMS (micro-electro-mechanical systems) audio sensor digital microphones. Imperceptibility, embedding capacity, and robustness are three main requirements for audio information-hiding techniques. To achieve the three main requirements, this study proposes a high-quality audio information-hiding technology in the wavelet domain. Due to the fact that wavelet domain provides a useful and robust platform for audio information hiding, this study applies multi-coefficients of discrete wavelet transform (DWT) to hide information. By considering a good, imperceptible concealment, we combine signal-to-noise ratio (SNR) with quantization embedding for these coefficients in a mathematical model. Moreover, amplitude-thresholding compression technology is combined in this model. Finally, the matrix-type Lagrange principle plays an essential role in solving the model so as to reduce the carrying capacity of network transmission while protecting personal copyright or private information. Based on the experimental results, we nearly maintained the original quality of the embedded audio by optimization of signal-to-noise ratio (SNR). Moreover, the proposed method has good robustness against common attacks.
Classification of Tetanus Severity in Intensive-Care Settings for Low-Income Countries Using Wearable Sensing
Authors: Lu Ping , Ghiasi Shadi , Hagenah Jannis , Hai Ho Bich , Hao Nguyen Van , Khanh Phan Nguyen Quoc , Khoa Le Dinh Van ,   VITAL Consortium, Thwaites Louise , Clifton David A. , Zhu Tingting
Published: August 2022

Infectious diseases remain a common problem in low- and middle-income countries, including in Vietnam. Tetanus is a severe infectious disease characterized by muscle spasms and complicated by autonomic nervous system dysfunction in severe cases. Patients require careful monitoring using electrocardiograms (ECGs) to detect deterioration and the onset of autonomic nervous system dysfunction as early as possible. Machine learning analysis of ECG has been shown of extra value in predicting tetanus severity, however any additional ECG signal analysis places a high demand on time-limited hospital staff and requires specialist equipment. Therefore, we present a novel approach to tetanus monitoring from low-cost wearable sensors combined with a deep-learning-based automatic severity detection. This approach can automatically triage tetanus patients and reduce the burden on hospital staff. In this study, we propose a two-dimensional (2D) convolutional neural network with a channel-wise attention mechanism for the binary classification of ECG signals. According to the Ablett classification of tetanus severity, we define grades 1 and 2 as mild tetanus and grades 3 and 4 as severe tetanus. The one-dimensional ECG time series signals are transformed into 2D spectrograms. The 2D attention-based network is designed to extract the features from the input spectrograms. Experiments demonstrate a promising performance for the proposed method in tetanus classification with an F1 score of 0.79 ± 0.03, precision of 0.78 ± 0.08, recall of 0.82 ± 0.05, specificity of 0.85 ± 0.08, accuracy of 0.84 ± 0.04 and AUC of 0.84 ± 0.03.
CHMM Object Detection Based on Polygon Contour Features by PSM
Authors: Zhuo Shufang , Huang Yanwei
Published: August 2022

Since the conventional split–merge algorithm is sensitive to the object scale variance and splitting starting point, a piecewise split–merge polygon-approximation method is proposed to extract the object contour features. Specifically, the contour corner is used as the starting point for the contour piecewise approximation to reduce the sensitivity of the contour segment for the starting point; then, the split–merge algorithm is used to implement the polygon approximation for each contour segment. Both the distance ratio and the arc length ratio instead of the distance error are used as the iterative stop condition to improve the robustness to the object scale variance. Both the angle and length as two features describe the shape of the contour polygon; they have a strong coupling relationship since they affect each other along the contour order relationship. To improve the description correction of the contour, these two features are combined to construct a Coupled Hidden Markov Model to detect the object by calculating the probability of the contour feature. The proposed algorithm is validated on ETHZ Shape Classes and INRIA Horses standard datasets. Compared with other contour-based object-detection algorithms, the proposed algorithm reduces the feature number and improves the object-detection rate.
Language Learning Motivation and Its Role in Learner Complaint Production
Authors: Yang He , Wu Xinxin
Published: August 2022

While motivation plays an important role in language learning, few attempts have been made to explore its significance in second language (L2) pragmatics learning. The current study investigated whether and how language learning motivation affects L2 pragmatics production. A total of 60 adult Chinese learners of English participated in this study. Data were elicited from a motivation questionnaire and a discourse completion task (DCT). The results revealed that L2 learners with high motivation performed better in making complaints in the target language than learners with low motivation. Moreover, learners’ levels of pragmatic production correlated positively with their overall L2 motivation, as well as with four motivational subscales, namely, attitudes towards learning English, ideal L2 self, intended learning efforts, and attitudes towards the L2 community. Regression analysis showed that learners’ attitude towards learning English best predicted their production of the speech act of complaints. The findings of this study support the role motivational dispositions play in learners’ L2 pragmatic production. The study provides insight into the interaction of L2 motivation and pragmatics learning.
Research on Joint Decision-Making of Timely Delivery, Product Quality and Marketing in Supply Chain Based on Differential Game
Authors: Qiao Hongfang , Lin Xiaowei , Zhou Xideng , Jiang Minglin
Published: August 2022

Due to the sudden surge of orders, it is difficult for suppliers with a limited capacity to ensure that all orders are delivered in time and all the products are qualified. Suppliers are likely to put more limited capacity into completing orders, thus ignoring the quality of products. This will easily lead to the occurrence of product quality events, and then affect the goodwill of enterprise products. The innovations of this paper are as follows: first, based on the above facts, a negative and dynamic correlation between the delivery level and the quality level is established, which has been involved in previous studies. Second, the joint decision model of timely delivery, product quality, and marketing is constructed. Thirdly, centralized decision-making is the best way of supply chain cooperation, and cost sharing contracts can coordinate the supply chain. This paper provides guidance for enterprise managers when making decisions on quality, marketing and delivery. It also provides the basis for enterprise managers to formulate effective cooperation models. We can draw some research implications: when consumers are less sensitive to timely delivery, enterprises should give some coupons and small gifts to consumers in exchange for the extension of delivery time and put their limited capacity into improving the product quality. When consumers are highly sensitive to timely delivery, they can outsource some orders to cost-effective and professional third-party enterprises, which not only improves the delivery rate but also improves the product quality.
Internships with Portuguese Speakers: Leadership, Organisational Culture and the Current Brain Drain
Authors: Macedo Matilde , Au-Yong-Oliveira Manuel , Walter Cicero Eduardo , Moreira Ana
Published: August 2022

Doing internships is increasingly common in Portugal, often being regarded as a prerequisite for entering the labour market. This trend reinforces the need to understand the interns’ perception of the ideal characteristics for this type of experience, in order to stop (or at least slow down) the brain drain that is currently felt. This exploratory research aims at reflecting on how organisations can contribute to successful internships. Themes such as the leadership and organisational culture of the host entity are addressed, areas which have been debated less often in the current literature. Our quantitative research was based on a survey, which obtained 143 responses from individuals with internship experience. Data were analysed using descriptive, reliability, inferential, and multiple linear regression analysis. The results from this study showcased a tendency toward servant leadership (in detriment to paternalistic or autocratic leadership) as being the most appropriate leadership style for an internship. It was also possible to emphasise some important points in an internship experience, including remuneration (desired by the interns) and the tasks performed (the interns want to be given responsibilities and meaningful work during their internship). Some of the results obtained are according to the state-of-the-art, however, others diverge.
Sustainable Development of Urbanization: From the Perspective of Social Security and Social Attitude for Migration
Authors: Zhang Yushi , Jiang Tianhang , Sun Jun , Fu Zitian , Yu Yanfeng
Published: August 2022

At present, many developing countries around the world are experiencing urbanization, and China has the largest scale of urbanization. The current literature mainly focuses on the relationship between economic factors, environmental factors and urbanization, ignoring the human factors. In fact, whether sufficient social security can be provided to solve people’s worries, as well as people’s social attitudes, has an important impact on their migration from rural areas to urban areas. By using the China General Social Survey (CGSS) 2018 data and constructing a binary logistic model, this paper studies the impact of social security on migration from rural areas to urban areas, as well as the mediating effects of people’s social attitudes. The results reveal that: (1) Social security has a significant positive effect on migration from rural areas to urban areas. (2) The improvement of the sense of fairness, happiness and security is conducive to the integration willingness and identity of the rural population and promotes urbanization. Therefore, social attitude plays an important mediating role. According to our study, policymakers need to consider how to build a suitable social security system and make rural residents feel safe and happy, so as to promote the sustainable development of urbanization.
How Can a Company Assess Social Needs to Reduce Poverty among Its Workers? The Case of the Export Banana Industries
Authors: Falk Anaïs , Macombe Catherine , Loeillet Denis , Deboin Jean-Marc
Published: August 2022

(1) Background: In Southern countries, companies that employ a large number of workers are concerned with poverty reduction, which is the priority of their CSR policy. The banana sector has made great efforts to calculate a “living wage”, but this is not sufficient. How do we assess a decent living standard in Southern countries, where basic social needs are rarely covered by the public authorities? (2) Methods: the selection and analysis of the living standard assessment methods are based on a systematic review of the literature. (3) Results: We selected 427 references in total and classified them into 10 method families. Among them, we have not found a ready-to-use method. The paper therefore suggests an innovative methodology (CSDA) inspired by Townsend’s non-monetary deprivation score and by the importance of social norms and ties. Instead of using a list of goods to define a decent living standard, the new method relies on access to services proven to be important for public health by covering social needs. Moreover, this method is easy to implement for the private sector, highlights the priority social needs for workers on which the company can act with its CSR policy, and allows for cross-country comparison. (4) Conclusions: This last point is crucial for the producers’ commercial negotiations with large-scale distribution and also to prevent the flight of workers to other activities or competitors. With regard to poverty alleviation, it will depend on how the company uses the results of the CSDA assessment.
In-Line Monitoring of Carbon Dioxide Capture with Sodium Hydroxide in a Customized 3D-Printed Reactor without Forced Mixing
Authors: Leventaki Emmanouela , Baena-Moreno Francisco M. , Sardina Gaetano , Ström Henrik , Ghahramani Ebrahim , Naserifar Shirin , Ho Phuoc Hoang , Kozlowski Aleksandra M. , Bernin Diana
Published: August 2022

Many industrial processes make use of sodium because sodium is the fifth most abundant metal and the seventh most abundant element on Earth. Consequently, there are many sodium-containing industrial wastes that could potentially be used for carbon capture, paving the way towards a circular and biobased economy. For example, a common industrial chemical is NaOH, which is found in black liquor, a by-product of the paper and pulp industry. Nonetheless, the literature available on CO2 absorption capacity of aqueous NaOH is scarce for making a fair comparison with sodium-containing waste. Therefore, to fill this gap and set the foundation for future research on carbon capture, the CO2 absorption capacity of NaOH solutions in a concentration range of 1–8 w/w% was evaluated, a wider range compared with currently available data. The data set presented here enables evaluating the performance of sodium-based wastes, which are complex mixtures and might contain other compounds that enhance or worsen their carbon capture capacity. We designed a customized reactor using a 3D-printer to facilitate in-line measurements and proper mixing between phases without the energy of stirring. The mixing performance was confirmed by computational fluid dynamics simulations. The CO2 absorption capacity was measured via weight analysis and the progress of carbonation using a pH meter and an FTIR probe in-line. At 5 w/w% NaOH and higher, the reaction resulted in precipitation. The solids were analyzed with X-ray diffraction and scanning electron microscope, and nahcolite and natrite were identified. With our setup, we achieved absorption capacities in the range of 9.5 to 78.9 g CO2/L for 1 w/w% and 8 w/w% of NaOH, respectively. The results are in fair agreement with previously reported literature, suggesting that non-forced mixing reactors function for carbon capture without the need of stirring equipment and a possible lower energy consumption.
Exploring the Sustainability of China’s New Energy Vehicle Development: Fresh Evidence from Population Symbiosis
Authors: Wang Shengyuan
Published: August 2022

It is particularly important to measure the growth prospects of new energy vehicles, especially electric vehicles, as they can effectively reduce the negative effects of the greenhouse effect. The population dynamics analysis model provides a method to comprehensively evaluate the growth mechanism, mode, and development prospects of new energy vehicles. In this research, the sales data of 20 automobile manufacturing enterprises were counted from the website database of the China Automobile Industry Association, and their development mechanism, development mode, and development trend were analyzed in order to help researchers understand the development prospects of China’s new energy vehicle enterprises. The conclusion is that the analysis results of the single population logistic model show that the intrinsic growth rate of Chinese new energy vehicle enterprises is generally relatively low. The intrinsic growth rate of China’s new energy automobile enterprises is lower than that of other mature traditional automobile manufacturing enterprises in China. The level of intrinsic growth rate of new energy vehicle enterprises is similar to that of declining enterprises with significantly declining sales. The Lotka–Volterra model provides the analysis results of the growth mechanism driven by market demand of automobile manufacturing sample enterprises. The market driven mode of China’s new energy vehicle enterprises is not obvious. It is difficult for the current development mechanism of China’s new energy vehicle enterprises to achieve the sustainability of growth. The optimization results of the MCGP model show that China’s new energy vehicle enterprises should transform to a market-driven development model.
Genetic Algorithm-Optimized Adaptive Network Fuzzy Inference System-Based VSG Controller for Sustainable Operation of Distribution System
Authors: Othman Mohd Hanif , Mokhlis Hazlie , Mubin Marizan , Ab Aziz Nur Fadilah , Mohamad Hasmaini , Ahmad Shameem , Mansor Nurulafiqah Nadzirah
Published: August 2022

To achieve a more sustainable supply of electricity and reduce dependency on fuels, the application of renewable energy sources-based distribution systems (DS) is stimulating. However, the intermittent nature of renewable sources reduces the overall inertia of the power system, which in turn seriously affects the frequency stability of the power system. A virtual synchronous generator can provide inertial response support to a DS. However, existing active power controllers of VSG are not optimized to react to the variation of frequency changes in the power system. Hence this paper introduces a new controller by incorporating GA-ANFIS in the active power controller to improve the performance of the VSG. The advantage of the proposed ANFIS-based controller is its ability to optimize the membership function in order to provide a better range and accuracy for the VSG responses. Rate of change of frequency (ROCOF) and change in frequency are used as the inputs of the proposed controller to control the values of two swing equation parameters, inertia constant (J) and damping constant (D). Two objective functions are used to optimize the membership function in the ANFIS. Transient simulation is carried out in PSCAD/EMTDC to validate the performance of the controller. For all the scenarios, VSG with GA-ANFIS (VOFIS) managed to maintain the DS frequency within the safe operating limit. A comparison between three other controllers proved that the proposed VSG controller is better than the other controller, with a transient response of 22% faster compared to the other controllers.
A Thorough Emission-Cost Analysis of the Gradual Replacement of Carbon-Rich Fuels with Carbon-Free Energy Carriers in Modern Power Plants: The Case of Cyprus
Authors: Nikolaidis Pavlos , Poullikkas Andreas
Published: August 2022

Global efforts towards de-carbonization give rise to remarkable energy challenges, which include renewable energy penetration increase and intermediate energy carriers for a sustainable transition. In order to reduce the dependence on fossil fuels, alternative sources are considered by commodities to satisfy their increasing electricity demand, as a consequence of a rise in population and the quantity of residential appliances in forthcoming years. The near-term trends appear to be in fuel and emission reduction techniques through the integration of carbon capture and storage and more efficient energy carriers, exploiting alternative energy sources, such as natural gas and hydrogen. Formulating both the fuel consumption and emission released, the obtained experimental results showed that the total production cost can be reduced by making use of natural gas for the transition towards 2035’s targets. Maximum profits will be achieved with hydrogen as the only fuel in modern power plants by 2050. In this way, the lowest electricity production can be achieved as well as the elimination of carbon dioxide emissions. Since the integration of renewable energy resources in the sectors of electricity, heating/cooling and transportation will continuously be increased, alternative feedstocks can serve as primary inputs and contribute to production cost profits, improved utilization factors and further environmental achievements.
The Social Quality of Design-Build: Lessons Learnt from Higher Education
Authors: Schreiber Franziska , Nöldeke Johannes , Setzen Špela , Kropp Cordula , Ley Astrid
Published: August 2022

The need for a systemic transformation of the building sector is increasingly recognized, but much of the current discussion and actions focus on the creation of technical innovation, while the question of how to improve the social quality of buildings and building processes is largely ignored. Socially engaged architecture more broadly and design-build projects in particular represent an exception in this regard. Design-build studios have emerged as a new teaching method at numerous universities in North America, Europe and elsewhere to equip students with the skills needed to address pressing sustainability issues. Most design-build projects include an explicit claim to social relevance and change and opt for a co-productive process. However, the extent to which such practices have the potential to enhance the social (and, ultimately, the ecological) sustainability of buildings and construction processes has been insufficiently assessed. Based on a comparative analysis of five design-build projects carried out at the University of Stuttgart, this paper discusses critical factors that influence both the (social) quality of the design-build process as well as its (built) outcome and impact. The findings offer important insights for future design-build projects and their underlying need for revised training and teaching curricula to equip future architects and planners with the necessary knowledge and skills to act as process designers and facilitators and to shape a more people-centered built environment.
Extending the Lifetime of Clothing through Repair and Repurpose: An Investigation of Barriers and Enablers in UK Citizens
Authors: Zhang Lisa , Hale Jo
Published: August 2022

Repairing and repurposing clothes can extend their lifetime, helping reduce the environmental impacts of the fashion industry. We aimed to investigate influences on clothing repair and repurpose using the Theoretical Domains Framework. A survey was conducted with a representative sample of 300 UK citizens. The frequency of, and influences on, clothing repair and repurpose behaviour were measured with self-report scales and a free-text item. Quantitative (logistic regression) and qualitative (thematic) analyses were used to identify barriers and enablers of behaviour. Findings showed that participants typically engaged in the behaviour every six months. The main barriers concerned a lack of skills, poor product design, unaffordability of repair services, and incongruence with identity. Key enablers concerned the ability to focus during DIY tasks, dynamic social norms, beliefs about benefits of repairing, emotional attachment to clothing, and having routines and habits of repairing. This study is the first to apply the Behaviour Change Wheel to identify intervention types and behaviour change techniques that can modify these influences, such as training workshops and the provision of free repair and repurpose services. Policy options were suggested to support implementation, such as extended producer responsibility. Awareness and skill-building campaigns, while important, are not enough to support behaviour change; structural and policy changes are needed.
An Improved Optimization Algorithm Based on Density Grid for Green Storage Monitoring System
Authors: Zhang Yanting , Zhu Zhe , Ning Wei , Fathollahi-Fard Amir M.
Published: August 2022

This study takes a sample of green storage monitoring data for corn from a biochemical energy enterprise, based on the enterprise’s original storage monitoring system while establishing a “green fortress” intending to achieve green and sustainable grain storage. This paper proposes a set of processing algorithms for real-time flow data from the storage system based on cluster analysis to detect abnormal storage conditions, achieve the goal of green grain storage and maximize benefits for the enterprises. Firstly, data from the corn storage monitoring system and the current status of research on data processing algorithms are analyzed. Our study summarizes the processing of re-al-time stream data together with the characteristics of the monitoring system and discusses the application of clustering analysis algorithms. The study includes an in-depth study of the green storage monitoring system data for corn and the processing requirements for real-time stream data. As the main novelty of this research, the optimization algorithm model is applied to the green storage monitoring system for maize and is validated. Finally, the processing results for the green storage monitoring data for maize are presented in graphical and textual formats.
Insights from User Preferences on Automated Vehicles: Influence of Socio-Demographic Factors on Value of Time in Romania Case
Authors: Andrei Liliana , Luca Oana , Gaman Florian
Published: August 2022

New transport technologies, such as autonomous vehicles, are increasingly discussed in the debate on the transition to a sustainable urban future. Automated vehicles (AVs) are expected to reduce the value of travel time (VoT), allowing the use of time for other types of activities during travel, including working, reading, sleeping, entertainment, etc. Our study aims to provide empirical insights on future modal choice preferences for regular trips for Romanian citizens, using a sample of 309 respondents to a web survey on issues related to automated vehicles. Using multinomial logistic models (MNL), we analysed the relationship between three mode choices: regular car, private automated vehicle, and shared automated vehicle, along with the individual and household characteristics. In addition, we calculated the VoT for each mode choice based on the results of MNL analysis. Results showed that VoT is strongly influenced by travel cost and travel time, by socio-economic characteristics such as age, gender, and education, and has the lowest value for the shared AV compared with a regular car or a private AV. Future research may conduct comparable studies in European countries but also explore the opinions and perceptions of vulnerable road users on AVs and VoT.
Positive Solutions for a Fractional Differential Equation with Sequential Derivatives and Nonlocal Boundary Conditions
Authors: Tudorache Alexandru , Luca Rodica
Published: August 2022

We study the existence of positive solutions for a Riemann–Liouville fractional differential equation with sequential derivatives, a positive parameter and a sign-changing singular nonlinearity, subject to nonlocal boundary conditions containing varied fractional derivatives and general Riemann–Stieltjes integrals. We also present the associated Green functions and some of their properties. In the proof of the main results, we apply the Guo–Krasnosel’skii fixed point theorem. Two examples are finally given that illustrate our results.
Experimental and Numerical Studies of the Heat Transfer in Thin-Walled Rectangular Tubes under Fire
Authors: Száva Renáta-Ildikó , Bolló Betti , Bencs Péter , Jármai Károly , Száva Ioan , Popa Gabriel , Asztalos Zsolt , Vlase Sorin
Published: August 2022

The paper studies, experimentally and numerically, the fire behavior of some structural elements of symmetric-tubular (rectangular in this study) shapes using modern dimensional analysis (MDA). A model at a certain scale of the real prototype is analyzed in order to obtain its response in case of fires. Experimental measurements are performed on a 1:10 scale model of a real support pillar and compared with the results of the numerical simulation. The obtained results can have useful applications in engineering practice, allowing fast obtaining of results with minimal costs.
Deep-Reinforcement-Learning-Based Intelligent Routing Strategy for FANETs
Authors: Lin Deping , Peng Tao , Zuo Peiliang , Wang Wenbo
Published: August 2022

Flying ad hoc networks (FANETs), which are composed of autonomous flying vehicles, constitute an important supplement to satellite networks and terrestrial networks, and they are indispensable for many scenarios including emergency communication. Unfortunately, the routing therein is largely affected by rapid topology changes, frequent disconnection of links, and a high vehicle mobility. In this paper, an intelligent routing strategy based on deep reinforcement learning (DRL) is proposed, which is decentralized and takes into account the status of symmetrical nodes in two hops. In order to perceive the local dynamics of the network as comprehensively as possible, the location, moving speed, load degree, and link quality of the nodes are considered into the setting process of state elements in the method. The nodes can select the neighboring node adaptively according to the Q values calculated by the model obtained through the training of Deep Q-Networks. The simulation and analysis show that the proposed method possesses good convergence characteristics and has obviously better performance compared with several common methods.
Optimal Design and Control of a Spoke-Type IPM Motor with Asymmetric Flux Barriers to Improve Torque Density
Authors: Wu Hao , Zhao Wenliang , Zhu Gefei , Li Min
Published: August 2022

This paper studies the optimal design and control scheme of a spoke-type interior permanent magnet motor (SIPM). An asymmetric rotor structure with flux barriers is designed to improve the torque density of SIPM. The design method improves the torque density by approximating the maximum value of the magnetic torque and the reluctance torque, wherein the torque components are separated by the frozen permeability method (FPM) to evaluate the contribution. This scheme does not increase the amount of permanent magnets or the motor size, and reduces motor weight while increasing motor torque output. Firstly, the asymmetric flux barriers are applied in a 27/4 SIPM to illustrate the design principle. Further, by optimizing the width of flux barriers, based on finite-element analyze (FEA), a higher torque density is obtained. Compared with the basic model, the output torque and the torque density of the optimal model are both increased. Based on the optimal model, an angle scanning method is proposed to orient the flux vector and dq-axis. Then, the mathematical model of the optimal model is established, and the maximum torque per ampere (MTPA) control system is designed. Compared with the conventional control system, the proposed control system has a higher torque per ampere (TPA), which shows that the designed control system can give full play to the advantages of the high torque density.
Searching for Orbits for a Mission to the Asteroid 2001SN263 Considering Errors in the Physical Parameters
Authors: de Almeida Junior Allan Kardec , Mescolotti Bruna Yukiko Pinheiro Masago , Chiaradia Ana Paula Marins , Gomes Vivian M. , de Almeida Prado Antonio Fernando Bertachini
Published: August 2022

The main goal of this paper is to search for orbits that can be used in the Brazilian proposed Aster mission. This mission is under study and its objective is to use a spacecraft to observe the system 2001SN263, which is a triple asteroid system. With respect to the two-body problem (spacecraft and the main asteroid), the symmetries of the orbits are broken by the oblateness of the main body of the system, the solar radiation pressure, and the gravitational attraction of the two moons of the main body. Additionally, the masses of these two moons have errors associated with their predicted values, which reinforce the asymmetry and require extra effort to maintain the observational objectives of the mission. The idea is to find orbits that remain for some time observing the three bodies of that system, even if the physical parameters of the bodies are not the ones expected from observations made from the Earth. This is accomplished by studying the effects of errors in all the physical properties of the three asteroids in the trajectories described by a spacecraft that is orbiting this system. Several important and useful trajectories are found, which are the ones that can observe the desired bodies, even if the physical parameters are not the expected ones. To express our results, we built time histories of the relative distances between each of the asteroids and the spacecraft. They are used to select the trajectories according to the amount of time that we need to observe each body of the system. In this way, the first objective of this research is to search for trajectories to keep the spacecraft close to the three bodies of the system as long as possible, without requiring orbital maneuvers. The errors for the masses of the two smaller and lesser known bodies are taken into consideration, while the mass of the most massive one is assumed to be known, because it was determined with higher precision by observations.
Molecular Collective Response and Dynamical Symmetry Properties in Biopotentials of Superior Plants: Experimental Observations and Quantum Field Theory Modeling
Authors: Chiolerio Alessandro , Dehshibi Mohammad Mahdi , Vitiello Giuseppe , Adamatzky Andrew
Published: August 2022

Trees employ impulses of electrical activity to coordinate actions of their bodies and long-distance communication. There are indications that the vascular system might act as a network of pathways for traveling electrical impulses. A question arises about the correlation and interplay between the molecular (microscopic) level and the macroscopic observable behavior of the system (the electrical impulses), for individual trees and as a component of the larger living ecosystem, the forest. Results from the “Cyberforest Experiment” in the Paneveggio forest (Valle di Fiemme, Trento, Italy) are presented. It is shown that: (i) biopotential features of xylem biomolecular activity can be correlated with the solar (and lunar) cycle, (ii) tree stubs show an electrical molecular activity that is correlated with that of neighboring trees, (iii) statistical features of spike-like peaks and entropy can be correlated with corresponding thermal entropy, and (iv) basic symmetries of the quantum field theory dynamics are responsible for the entanglement phenomenon in the molecular interactions resulting in the molecular collective behavior of the forest. Findings suggest implementing technology that goes in the direction of understanding the language of trees, eventually of fungi, which have created a universal living network perhaps using a common language.
Selected Techniques for Cutting SOx Emissions in Maritime Industry
Authors: Papadopoulos Christos , Kourtelesis Marios , Moschovi Anastasia Maria , Sakkas Konstantinos Miltiadis , Yakoumis Iakovos
Published: August 2022

Burning fuels with high sulfur content leads to SOx emissions, especially SO2, which leads to various environmental and health problems. The maritime sector is responsible for 13% of the global anthropogenic emissions of SO2. Thus, the International Maritime Organization (IMO) has issued a protocol, known as MARPOL Annex VI, which aims to further limit SO2 emissions derived from ships along with NOx, particulate matter and volatile organic compound emissions. This has led ship owners and operators to choose between more expensive fuels with low sulfur content or to apply a DeSOx solution, which still allows them to use the cheapest heavy fuel oil. The current work reviews the state-of-the-art DeSOx solutions both for the maritime and land-based sector. Next, it proposes an alternative cheaper and environmentally friendly DeSOx solution based on the selective reduction of SO2 to elemental sulfur by utilizing a catalytic converter based on metal oxides, similar to the ones used in the automotive industry. Finally, it reviews the most promising metal oxide catalysts reported in the literature for the selective reduction of SO2 towards elemental sulfur.
Structural, Functional and Neurochemical Cortical Brain Changes Associated with Chronic Low Back Pain
Authors: Medrano-Escalada Yara , Plaza-Manzano Gustavo , Fernández-de-las-Peñas César , Valera-Calero Juan Antonio
Published: August 2022

Chronic low back pain (CLBP) is one of the most prevalent musculoskeletal disorders, being one of the leading contributors to disability worldwide and involving an important economic and social burden. Up to 90% of CLBP is non-specific (not associated with specific injuries), with a chronicity expectation estimated at 10%. Currently, motivational and emotional central circuits are being investigated due to their role in CLBP persistency and chronification. Therefore, this narrative review aimed to summarize the evidence regarding the cortical brain changes described for proposing novel multidisciplinary approaches. Novel advances in neuroimaging techniques demonstrated structural (e.g., decrease in the grey matter located at the dorsolateral prefrontal cortex), functional (e.g., connectivity impairments in those areas involved in pain processing), and neurochemical changes (e.g., decrease in cerebral metabolites). In addition, significant changes were found in the primary somatosensory and motor cortex, contributing to the alteration of low back muscles activation and function.
Full-Thickness Craniodural Metastasis with Leptomeningeal Infiltration of Salivary Origin: A Radiological Lesson and a Technical Remark
Authors: Pesce Alessandro , Armocida Daniele , Fiorentino Francesco , Ciarlo Silvia , La Pira Biagia , Salvati Maurizio , Frati Alessandro , Pompucci Angelo , Palmieri Mauro
Published: August 2022

Calvarial metastases are a relatively rare entity, with an overall incidence of 3–4%. Among these cases, metastases arising from salivary gland cancers are even rarer; in fact, large studies regarding salivary gland tumors showed that brain metastases are observed in 0.8% of the cases. Generally, bone metastases have been described in proximity to primary tumors, while bloodstream-disseminated lesions are often located inside the brain parenchyma. During every surgical step, traction on lower-lying infiltrated tissues must be avoided in order to successfully remove the lesion. This case report presents the first ever case of a 67-year-old woman affected by submandibular gland undifferentiated adenocarcinoma metastasis with a full-thickness involvement of the calvarium, pachy- and leptomeninges.
Impact of COVID-19 and Socioeconomic Factors on Delays in High-Risk MRI Breast Cancer Screening
Authors: Teng Helena , Dang Wilfred , Curpen Belinda
Published: August 2022

The purpose of this study is to investigate if there was a delay in high-risk MRI breast cancer screening in our local region, if this delay is ongoing despite COVID-19 vaccinations, and if demographic and socioeconomic factors are associated with these delays. Six-hundred and sixty-five high-risk breast patients from 23 January 2018–30 September 2021 were included. Delays were determined by comparing the time in between each patients’ MRI screening exams prior to the COVID-19 pandemic to the time in between MRI screening exams during the height of the COVID-19 pandemic as well as the time in between exams when our patients started receiving vaccinations. Delays were analyzed via logistical regression with demographic and socioeconomic factors to determine if there was an association between these factors and delays. Significant time delays in between MRI screening exams were found between the pre-COVID timeframe compared to during the height of COVID. Significant time delays also persisted during the timeframe after patients started getting vaccinations. There were no associations with delays and socioeconomic or demographic factors. Significant time delays were found in between MRI high-risk breast cancer screening examinations due to the COVID-19 pandemic. These delays were not exacerbated by demographic or socioeconomic factors.
A Metabolomic Approach to Assess the Toxicity of the Olive Tree Endophyte Bacillus sp. PTA13 Lipopeptides to the Aquatic Macrophyte Lemna minor L.
Authors: Papadopoulou Evgenia-Anna , Giaki Katerina , Angelis Apostolis , Skaltsounis Alexios-Leandros , Aliferis Konstantinos A.
Published: August 2022

Pesticides represent a major human input into the ecosystem, posing a serious risk to non-target organisms. Therefore, there is pressure toward the reduction in their use and the discovery of alternative sources of bioactivity. Endophytic microorganisms represent a source of bioactivity, whose potential for plant protection has been recently established. In this context, an olive tree endophytic Bacillus sp. was isolated, exhibiting superior antifungal activity, mainly attributed to its major surfactin, iturin, and fengycin and the minor gageotetrin and bacilotetrin groups of lipopeptides (LP). Based on the potential of LP and the lack of information on their toxicity to aquatic organisms, we have investigated the toxicity of an LP extract to the model macrophyte Lemna minor L. The extract exhibited low phytotoxicity (EC50 = 419 μg·mL−1), and for the investigation of its effect on the plant, GC/EI/MS metabolomics was applied following exposure to sub-lethal doses (EC25 and EC50). Results revealed a general disturbance of plants’ biosynthetic capacity in response to LP treatments, with substantial effect on the amino acid pool and the defense mechanism regulated by jasmonate. There are no previous reports on the phytotoxicity of LP to L. minor, with evidence supporting their improved toxicological profile and potential in plant protection.