bluuebunny/crossref_metadata_2025 huggingface dataset:
Topological and dynamical phase transitions in the Su–Schrieffer–Heeger model with quasiperiodic and long-range hoppings
Authors: Zhang Wei-Jie , Wu Yi-Piao , Tang Ling-Zhi , Zhang Guo-Qing
Published: June 2022

Disorders and long-range hoppings can induce exotic phenomena in condensed matter and artificial systems. We study the topological and dynamical properties of the quasiperiodic Su–Schrier–Heeger model with long-range hoppings. It is found that the interplay of quasiperiodic disorder and long-range hopping can induce topological Anderson insulator phases with non-zero winding numbers

ω
=
1
,
2
,

and the phase boundaries can be consistently revealed by the divergence of zero-energy mode localization length. We also investigate the nonequilibrium dynamics by ramping the long-range hopping along two different paths. The critical exponents extracted from the dynamical behavior agree with the Kibble–Zurek mechanic prediction for the path with

W
=
0.90
.

In particular, the dynamical exponent of the path crossing the multicritical point is numerical obtained as

1
/
6
∼
0.167
,

which agrees with the unconventional finding in the previously studied XY spin model. Besides, we discuss the anomalous and non-universal scaling of the defect density dynamics of topological edge states in this disordered system under open boundary condictions.
Confinement of passing and trapped runaway electrons in the simulation of an ITER current quench
Authors: Särkimäki Konsta , Artola Javier , Hoelzl Matthias , the JOREK Team
Published: June 2022

Runaway electrons (REs) present a high-priority R&D issue for ITER but little is known about the extent to which RE generation is affected by the stochastic field intrinsic to disrupting plasmas. RE generation can be modelled with reduced kinetic models and there has been recent progress in involving losses due to field stochasticity, either via a loss-time parameter or radial transport coefficients which can be estimated by tracing test electrons in 3D fields. We evaluate these terms in ITER using a recent JOREK 3D MHD simulation of plasma disruption to provide the stochastic magnetic fields where RE markers are traced with the built-in particle tracing module. While the MHD simulation modelled only the current quench phase, the case is MHD unstable and exhibits similar relaxation as would be expected during the thermal quench. Therefore, the RE simulations can be considered beginning right after the thermal quench but before the MHD relaxation is complete. The plasma is found to become fully stochastic for 8 ms and the resulting transport is sufficient to overcome RE avalanche before flux surfaces are reformed. We also study transport mechanisms for trapped REs and find those to be deconfined as well during this phase. While the results presented here are not sufficient to assess the magnitude of the formed RE beam, we show that significant RE losses could be expected to arise due to field stochasticity.
Development of irradiation tolerant tungsten alloys for high temperature nuclear applications
Authors: Terentyev Dmitry , Jenus Petra , Sal Elisa , Zinovev Aleksandr , Chang Chih-Cheng , Garcia-Rosales Carmen , Kocen Matej , Novak Saša , Van Renterghem W.
Published: June 2022

Development of refractory metals for application as plasma-facing armour material remains among priorities of fusion research programmes in Europe, China and Japan. Improving the resistance to high temperature recrystallization, enhancing material strength to sustain thermal fatigue cracking and tolerance to neutron irradiation are the key indicators used for the down selection of materials and manufacturing processes to be applied to deliver engineering materials. In this work we investigate the effect of neutron irradiation on mechanical properties and microstructure of several tungsten grades recently developed. Neutron irradiation campaign is arranged for screening purposes and therefore is limited to the fluence relevant for the ITER plasma facing components. At the same time, the neutron exposure covers a large span of irradiation temperatures from 600 up to 1000 °C. Four different grades are included in the study, namely: fine-grain tungsten strengthened by W-carbide (W–4wt.% W2C), fine-grain tungsten strengthened by Zr carbides (W–0.5% ZrC), W alloyed with 10 at.% chromium and 0.5 at.% yttrium (W–10Cr–0.5Y) and technologically pure W plate manufactured according to the ITER specification by Plansee (Austria). The strengthening by W2C and ZrC particles leads to an enhanced strength, moreover, the W–0.5ZrC material exhibits reduced DBTT (compared to ITER specification grade) and is available in the form of thick plate (i.e. high up-scaling potential). The W–10Cr–0.5Y grade is included as the material offering the self-passivation protection against the high temperature oxidation.
QoS-Aware Traffic Offloading for Energy Efficient D2D Communication in 5G Network for IoT application
Authors: Chandra Saurabh , Prateek  , Arya Rajeev
Published: June 2022

In Device-to-Device (D2D) communication, where base station (BS) suffers from the issues of unbalanced loads of traffic due to interference which requires low power consumption. The energy efficiency of D2D communication in 5G Network for IoT application is a critical issue due to power consumption at BS is considerably high. In this paper, we propose D2D-based traffic offloading scheme that smartly allocate the traffic between D2D and base station while satisfying Quality of Service (QoS) requirements, which helps to minimize the load from the base station based on the information of users’ locations with low power consumption and high spectral efficiency which fulfils the QoS requirements. We make our proposed algorithm more efficient with less complexity which improves spectral efficiency, lowers the latency with minimum QoS performance of the network. With the help of simulation parameter, we obtained some results which determines that the proposed approach significantly outperforms the other existing approaches in terms of delay or latency, average energy consumption and average computing time up to 72%, 76% and 86% when the number of tasks/loads is 100 while satisfying the users’ demand. The work proposed in this article may be useful in energy efficient 5G-D2D Network for IoT application.
Analysis and Enhancement of Q-Factor in Thin-Film Bulk Acoustic Wave Resonator (FBAR)
Authors: Joshi P K , Latwe K R , Hasamnis M A
Published: June 2022

In MEMS technology, MEMS Resonators has shown high potential applications in wireless communications such as Bluetooth and WIFI range. The Bulk Acoustic Wave (BAW) Resonator is a device which has more potential to meet the needs of today’s wireless technology. The Acoustic wave technology has attracted more attention and it’s an effective solution for achieving high-performance RF filters applications due to its low cost and small size of the device. The performance analysis of thin film bulk acoustic resonator (FBAR) by varying different piezoelectric material, piezoelectric material’s thickness and electrode materials is demonstrated in this paper. It is understood that the Quality factor is considerable higher for AlN as compared to ZnO and LiNbO3. Among all the materials, Aluminium electrode achieved maximum quality factor. As the thickness of piezo material decreases, it is found that the resonant frequency and Quality factor increases. Along with the Quality Factor, the top and bottom electrode thickness has a significant impact on the resonant frequency.
Live Streaming of Face Mask and Body Temperature Detection System using Transfer Learning and IoT
Authors: Singh Nutan , Tripathi Priyanka
Published: June 2022

Since the outbreak of COVID-19 pandemic, enormous development has been done in computer vision systems in face masks and temperature detection. To enforce the mandate for wearing the mask in public places, the authors have suggested a solution using transfer learning (MobileNetV2) architecture as a foundation for image classification. The proposed solution is embedded devices with Raspberry Pi4 and python packages viz TensorFlow, OpenCV, and Keras. In this Work, a combination of transfer learning and IoT has been worked out using live streaming to detect an appropriate use of face masks along with body temperature. This technique includes the Single Shot Single box and Multi-box identification of the face mask. Further, a person can check the Temperature at the entrance. This temperature sensor is in noncontact mode, which senses a temperature from 2 cm to 5 cm and is displayed through LCD. It sends the data to the cloud for visualization and analysis, and an alert message is sent in a real-time environment based on that analysis.
Low Cost Hand Held Device For Leakage Detection From Microwave Oven
Authors: Mishra R , Chaurasiya U , Srivastava R , Shukla N K , Misal Ashish Kumar
Published: June 2022

Microwave heating systems for industrial uses, notably for food and farm goods have been extensively developed. Microwave energy is now being used in many ways, with greater focus on consumption. If utilized for a consumer product as a power source, microwaves are typically employed in a totally shielded enclosure that does not allow access while the microwave source is running. The radio frequency (RF) leakage above 5mW (+ 10 dBm) is dangerous to humans, according to the World Health Organization (WHO) guideline. This manuscript focuses on the low cost hand held device for detection of microwave energy radiation because it is very hazardous for human body. This kind of device will be very helpful for clean and green society.
A Survey on IBM Watson and Its Services
Authors: Kumar Avinash , Tejaswini Pallapothala , Nayak Omprakash , Kujur Anurag Deep , Gupta Rajkiran , Rajanand Ashish , Sahu Mridu
Published: June 2022

Artificial Intelligence (AI) is changing the modern way of lifestyle by helping the person do their jobs in an efficient manner. The AI is currently in its starting phase and from now on it is of great use. IBM Watson is an AI which is used globally by different organizations, institutes and corporations. In this paper we have created a chatbot using IBM Watson Assistance which is helpful in querying about the disease and hospitals related query. This paper also discusses IBM Watson in detail, its applications, its working and case studies on the use of IBM Watson in the field of healthcare, visual recognition and a software company named BOX.
RETRACTED: Design and Development of Person Re-Identification system based spatial features
Authors: Bethu Srikanth , Babu B Sankara , Suneetha Ch. , Indupriya B , Ramya Manaswi V
Published: June 2022

Primary intention of this research is to design and develop an effectual approach for re-identifying the persons. The proposed approach involves four stages named human identification, object tracking, feature extraction, and matching. The four stages will be implemented by matching the probe videos and gallery videos. Initially, the videos will be subjected to the human identification phase. First stage will be the identification of human depending on the spatial features. It is important to consider that person re-identification will be carried out using the video surveillance data which can be probe data or gallery data. For human identification, the spatial features will be extracted and subjected to gait based Bayesian network for identifying the humans. Then, the object tracking phase will be carried out for tracking the objects from the videos. Here, the Neighborhood Search Algorithm will be used for tracking the objects. Then, the tracked objects will be given to the feature extraction process in which the features like mean, variance, speed, and motion deviations will be extracted. Finally, in matching phase, the matching will be performed between the probe videos and gallery videos and the person re-identification will be done using the extracted features based on the Bayesian probability-based matching. Finally, the matched outputs will be utilized for re-identifying the persons. The implementation of the proposed approach will be done using the Grid and Caviar Data sets. The performance of the proposed technique will be evaluated using three metrics, such as accuracy, sensitivity and specificity and will be compared with that of existing methods.
Deep Learning Techniques on Brain Images
Authors: Sahu Mridu , Upadhyay Yogita , Khoriya Namrata , Biswas Abhilash , Chandrawanshi Manas , Patel Omprakash
Published: June 2022

Our brain is the most composite organ of the human body with an aggregation of 100 million nerves which communicate in a nexus of synapses. All the activities from thinking, memorizing, storing information, the functioning of other organs of the body are all managed by the brain. Any disease which affects the brain affects the whole of the body. Severe brain diseases paralyze the body. Some of the common categories of brain diseases are seizures, trauma, tumor, and infections. Alzheimer’s, Epilepsy, Brain Cancer, and brain disorders. Research to use Image Processing Techniques in the field of brain diseases still has a long way to go. This paper is one such small step in the process of understanding Deep Learning in brain imaging. It is a detailed study on brain diseases and how algorithms can help in the current treatment. CNN is discussed in detail with its architecture and the reason of its popularity is discussed. This particular paper also comprises a case study of one such disease i.e brain tumor and the effect of various parameters in improving the accuracy of Convolutional neural networks on this particular data-set. The case study involves augmenting the data and applying CNN on it. The effect of CNN is then studied on the basis of three parameters which are Optimizers, Activation Function, and Loss Function. A comparative analysis is then drawn out among all the possible combinations and the best combination of these parameters are found. The models were evaluated in terms of accuracy and time required to train the algorithm. Using the comparison table important findings and conclusions were drawn out.
Predicting Heart Diseases through Feature Selection and Ensemble Classifiers
Authors: Diwan Shivangi , Thakur Gajendra Singh , Sahu Sunil K. , Sahu Mridu , Swamy N. K.
Published: June 2022

Heart diseases or Cardiovascular Diseases are the leading cause of death globally. Amid the Covid-19 pandemic, the toll has further increased and is prevalent among all age groups. The reasons are associated with various side effects of lockdown or socio-economic affairs. It becomes extremely important to strengthen our research on diagnosis systems to timely and accurately identify the disease. This paper is an attempt to predict a healthy or heart patient using ensemble machine learning methods depending on selected features. The proposed model shows that after performing feature selection the ensemble models give optimum accuracy with significantly lesser features.
The effect of immersion time on singlemode-tapered multimode-singlemode (STMS) fabrication using a chemical etching method
Authors: Lesa A. D. , Puspita I. , Hatta A.M. , Kurniawan F. , Koentjoro S.
Published: June 2022

Singlemode-Multimode-Singlemode (SMS) is one of the fiber optic sensor structures that is widely applied for many sensing applications. High sensitivity is the preferred characteristic of SMS fiber structure. In this paper, a tapered structure is introduced to the SMS fiber structure to increase its performance. The tapered structure is made by the etching method by immersing the SMS multimode fiber in hydrofluoric acid (HF) solution. The immersion time was varied 5, 10, 15 and 20 minutes. The diameter of the multimode fiber decreases with the longer immersion time, while the length does not change. The STMS transmission spectrum was measured to investigate its performance. The chemical etching method using HF solution for tapering the SMS fibers has great potential as a simple method to achieve a smaller radius without lengthening multimode fibers.
Aero-acoustics Investigation of a Bionic Airfoil Horizontal Axis Wind Turbine Using LES-DCS Approach
Authors: Wu Weimin , Dong Wenling , Li Shiwei , Zhang Suocheng
Published: June 2022

The wind turbine noise has become an important issue in the current green energy field, therefore, it is necessary to use new and advantageous methods to study the problem. This research employed the LBM-DCS method to investigate the wake sound radiation characteristics for a bionic airfoil horizontal axis wind turbine, combining the large eddy simulation (LES) model and the wall-adapting local eddy-viscity (WALE) model. The obtained results show that the aeroacoustic model used here is reasonable and effective, which are consistent with the relevant experimental measurement result. The appearance and changing characteristics of the acoustic radiation ring have been discussed and analyzed to a certain extent. Based on the accumulation of this research, we will combine more experimental data to carry out a further systematic investigation on the acoustic radiation characteristics to the wind turbine.
The comparison of adjoint-based grid adaptation and feature-based grid adaptation method
Authors: Cui Pengcheng , Zheng Yongqian , Xu Peimin , Li Bin , Ma Mingsheng , Zhou Guiyu
Published: June 2022

Grid adaption is a popular method to enhance the resolution of flow field and the precision of numerical simulation, which automatically optimizes the grid distribution instead of manual complicated work. There exist usually two grid adaptation methods, the feature based grid adaption and adjoint based grid adaption, the former focuses on shocks, vortexes and other features of flow field, and the latter focuses on lift, drag and other aerodynamic characteristics. The comparison of adjoint based grid adaption and feature based grid adaption method is investigated in this paper. Numerical simulations show that both feature adaption and adjoint adaption could improve the resolution of flow field and the precision of numerical simulation such as lift and drag. As for the flow features, the feature adaptation could capture the obvious shock waves and vortexes in the flow field, the adjoint adaptation, however, only captures the flow features that are contributory to the accuracy of aerodynamic characteristics. As for the aerodynamic characteristics, some shock waves and vortexes have little influences to the forces, so the feature adaptation is not efficient as adjoint adaptation, which could greatly improve the accuracy of aerodynamic characteristics.
The influence of wind turbine blade rotation on Wind direction meter
Authors: Tian Lizhu , Zhou Yaqiang , Jiang Zhiwen , Li Yapeng , Wu Zhaohe , Qi Chenglong , Gou Yanxu , Xu Yonghe , Du Dayu , Wang Bao , Wu Yuan , Feng Wei , Li Peng
Published: June 2022

In this paper, a numerical analysis of the influence of the wind turbine impeller on the wind direction indicator is carried out. The layout position of the wind direction indicator and the wind speed change are analysed respectively, and the current equipment position is analysed whether it is suitable for the installation of wind measurement equipment, and the best layout is given.
Overload Response Analysis of UAV in Severe Weather
Authors: Zhu Ting , Xia Shenglin , He Shiwei , Huang Kunshan
Published: June 2022

Turbulence will occur when the aircraft passes through the gust area, which will affect the handling quality and ride quality of the aircraft, increase the bending moment of the wing root and shorten the fatigue life of the structure. At present, in engineering calculation, when the gust load of UAV is considering, the UAV is usually regarded as a rigid body according to the general specification, and the overload response is obtained by solving the dynamic equations of rigid body. The flexibility of UAV is not considered, and the more realistic harsh wind field environment is not considered, so there is a certain deviation between the results and the actual values. Therefore, the gust load was studied considering the aircraft elasticity and the more realistic harsh wind field environment, and compares the calculation results with that considering the standard wind field, and makes a full assessment of the gust overload of UAV. It provides the basis for the design of aircraft structure strength and flight safety, and has important engineering significance.
Study on effect of boundary conditions on simulation of wind flow in mountainous area
Authors: Yin Yuan , Li Yangsen , Lin Ruizong , Liu Zhiwei , Fu Benzhao , Huang Guo , Zhang Hongjie
Published: June 2022

The simulation analysis of wind flow in mountainous area can assist the design of the transmission line. The conventional square computational domain is not conducive for the condition of different wind directions. In this paper, a circular computational domain is proposed for the solution of wind flow in mountainous area in the condition of different wind directions. A square computational domain and a circular one are used to solve the wind flow around the standard hill model. The simulation accuracy of the circular computational domain is verified by the wind profiles at the windward slope, the top of the slope and the leeward slope.
Numerical simulation of sound scattering by a convected vortex
Authors: Ma Ruixuan , Wu Conghai , Han Shuaibin , Zhang Shuhai
Published: June 2022

The sound scattering by a convected isentropic vortex is numerically studied by solving the linearized Euler equations (LEE) with high-fidelity finite-difference methods and non-reflecting boundary conditions. Our computations are in good agreement with previous studies. Simulations for the scattering from a Taylor vortex at a range of convected velocity reveal that the convection of the vortex leads to the spectral broadening of the incident waves. The power spectral density analyses of the scattered pressure in the frequency domain show that the range of the spectral broadening is strongly influenced by convected velocity. This fact can be explained by the relative motion between the vortex and observer associated with the Doppler factor. The sidebands originating from the scattered fields at a fixed point in the frequency domain can be associated with the scattered beams observed in the case of scattering by a steady vortex.
CFD analysis of flow field and hydrodynamic compensation of poppet valve
Authors: Li Ruichuan , Liu Jilu , Ding Xinkai , Cheng Yi , Liu Qi
Published: June 2022

The steady-state hydrodynamic force of cartridge valve poppet valve core reduces the stability of cartridge valve. A circular arc structure is added to the main valve core of the poppet valve to compensate the steady-state flow force. Referring to the structure and parameters of the actual cartridge poppet valve, the three-dimensional geometric model of the flow channel in the valve is established with UG software. CFD method is used to calculate and analyze the flow state of fluid in the poppet valve under the working state of the valve core, and the influence of the arc size and position of the valve core on the steady-state hydrodynamic compensation of the main valve core is studied. The results show that the circular arc structure can realize the hydrodynamic compensation of the valve core and increase the stability of the valve core. When the opening amount is small, properly increasing the height h of the circular arc structure can increase the static hydrodynamic compensation of the valve core; Keep the circular arc structure size L less than 1mm, and the static hydrodynamic compensation effect of the valve core is better.
Lattice Boltzmann simulations of gas bubble transport in proton exchange membrane water electrolysis cells
Authors: Li Gang
Published: June 2022

Gas/liquid two-phase transport is the key fundamental scientific issue in the proton exchange membrane (PEM) water electrolysis cell, which has important effects on the overall performance of water electrolysis and microstructure optimization. In this study, a combination of the lattice Boltzmann two-phase model and the QSGS numerical method was used to numerically model the porous diffusion layer and the micro-channel structure, and investigate the effects of porosity and wettability properties on the gas/liquid two-phase transport process. Simulation results show that the value of porosity will obviously affect the association and distribution pattern of solid particles inside the porous diffusion layer, and the reduction of porosity will cause the association part of solid particles to be narrower and longer, resulting in complex and variable pore channels. Some closed pore channels will appear inside the diffusion layer, which is not conducive to the smooth transmission of gas bubbles. In addition, the increase of contact angle will enhance the interaction force between the bubble and the solid wall, making it difficult for the bubble to fall off from the solid surface. Moreover, the increased interaction force will slow down the sliding speed of gas bubbles, which will result in the fusion of more gas bubbles and increase the risk of blocking the flow micro-channel. This study has initially grasped the mechanisms of micro/meso scale gas bubble transport in the PEM water electrolysis cell, which will provide theoretical basis for the optimized development of high-performance water electrolysis system for hydrogen production.
Study on Rebounding Height of Capsule-shaped Object Based on Serial Coefficient of Restitution
Authors: Pang Bowen , Wang Xinkai , Shuo Liu , Guo Junxi , Hao Guancheng , Pan Wang , Ju Liping
Published: June 2022

The capsule-shaped object, when vertically released at certain initial angular velocity, can easily rebound to exceed the release height. The high-speed camera is used to record experimental images. The software, Tracker, is used to track experimental data. Finally, serial coefficient of restitution and spin parameter can be statistically summarized. MATLAB is used to process images to obtain the correlation between relevant data of the capsule rebounding status and serial coefficient of restitution, and bases for spin direction changes before and after rebounding of the capsule. ANSYS is employed to obtain simulation data. At last, evidence is provided to substantiate that the serial coefficient of restitution can, under some conditions, allow the capsule-shaped object can rebound higher than the release height, and that the spin direction and status of the capsule-shaped object can be identified by the value of spin parameter.
The water impact load study for seaplane during get-off and alighting process on rough water
Authors: Huang Miao , Wu Bin , Li Chenghua
Published: June 2022

The scaled model tank test on rough water of a seaplane is conducted, and then we study the influence rules of wave length, wave height and test velocity on water load systematically, the results turn out to the that: the water load decreases as the wave length goes up, it decreases rapidly when the model moves at relatively high speed and slowly when model moves at low speed. as the test velocity goes up, the water load increases much more rapidly at short wave length than that at long wave length. when the model remains navigation status, the water load change slightly but rapidly in a linear fashion as to wave height when model remains planning status. in conclusion, the water load gets relatively high value at the status of higher speed and shorter wave length, and relatively low value at the status of lower speed and longer wave length.
Formation of accretion disk by hydrodynamic subcritical transition
Authors: He Ziting
Published: June 2022

This work employs input-output analysis that is computationally efficient to provide insight into the dominant length scale the transition mechanism in rotating plane Couette flow that is relevant to the accretion disk. We also incorporate componentwise analysis to isolate the effect of different input body forces and different output velocity responses. We compared results associated with three different Reynolds numbers and rotation numbers considering both the overall effect and the effect under isolated input and output directions. We observe different patterns in which the maximum energy amplification strength changes as Reynolds number and rotation number change. We also derive the scaling law of the largest input-output gain over Reynolds number and rotation number, which suggests a higher rotation rate is playing a stabilizing role. We observe that the maximum amplification at rotation number equal to one shows symmetry against the lift-up mechanism in non-rotating plane Couette flow. As the stabilizing effect of rotation is further increased, we observe the most amplified flow structures are more elongated in the spanwise direction reminiscent of the Taylor-Proudman effect.
Design of Gas Drainage Monitoring System Based on Siemens S7-1500 PLC and WinCC
Authors: Wang ZuXun
Published: June 2022

In order to ensure the reliable and stable operation of the gas drainage system and ensure the safe production of coal mines, a gas drainage monitoring system is designed. The monitoring system adopts Siemens S7-1500 series PLC as the core control unit. By configuring function modules and cooperating with WinCC configuration software to carry out the program design of the upper computer, the one-key control and automatic regulating of the gas drainage system is realized. The monitoring system adopts smart sensors, and improves the anti-interference ability of the system through digital signal transmission, adopts PID and cascade PID advanced control strategies to control the flow and pressure, and improves the regulating accuracy of the drainage system, adopts the limit threshold method and data mutation method combined with early warning reduces the unplanned shutdown of the drainage pump and improves the working efficiency of the drainage pump.
Human joints estimation system of rescue robot with occlusion
Authors: Fang Zhenghui , Wang Anna , Bu Chunguang , Sui Jin , Fan Xiaoliang
Published: June 2022

The human body is often in a partially visible state during rescue at the disaster site. At the same time, when the human body is grasped, the camera located on the actuator at the end of the robotic arm cannot fully bring the human body into the field of view. The existing human pose estimation algorithms do not perform well in this situation, and a joint detection method that can estimate the complete human pose through partial human body information and can perform data refresh in real time is required. We use the occlusion part classification module to extract the weight vector, re-weight it and the joint features extracted from AlphaPose, and add human body geometric constraints when generating 3D human body joints to obtain more accurate 3D human body joint positions. Finally, the robot is successfully used to complete the human grasping experiment, which verifies the effectiveness of the algorithm.
Motion Planning of Unmanned Aerial Vehicle Based on Rapid-exploration Random Tree Algorithm
Authors: Cai Fake , Liu Danyang , Yuan Weihan , Ding Shuo , Ning Yongxu , Yue Chenyang
Published: June 2022

In the study of route planning problems in complex environments, in order to reduce the flight cost of unmanned aerial vehicles (UAVs), it is necessary to achieve a better balance between planning time and path quality. This paper utilizes the Rapid-exploration Random Tree (RRT) algorithm for motion planning of a fixed-wing UAV and a multi-rotor UAV (i.e., a quad-rotor UAV), and gives the origin and destination locations on a 3-D map. By following aerodynamic constraints such as maximum roll angle, flight path angle, and airspeed, a collision-free and flight-friendly path is found through simulation. In addition, this paper employs a path smoothing algorithm to simplify the 3-D Dubins path and generates the shortest trajectory. The simulation results show that the RRT and the optimization method have faster convergence speed and shorter search time, reduce redundant planning points, shorten the planning track, and improve the track planning efficiency.
Direct detection of charged particles with SiPMs
Authors: Carnesecchi F. , Vignola G. , Agrawal N. , Alici A. , Antonioli P. , Arcelli S. , Bellini F. , Cavazza D. , Cifarelli L. , Colocci M. , Durando S. , Ercolessi F. , Garbini M. , Giacalone M. , Hatzifotiadou D. , Jacazio N. , Margotti A. , Malfattore G. , Nania R. , Noferini F. , Pinazza O. , Preghenella R. , Ricci R. , Rignanese L. , Rubini N. , Scapparone E. , Scioli G. , Strazzi S. , Tripathy S. , Zichichi A.
Published: June 2022

The direct response of Silicon PhotoMultipliers being
traversed by a MIP charged particle have been studied in a
systematic way for the first time. Using beam test data, time
resolution and the crosstalk probability have been measured. A
characterization of the SiPM by means of a laser beam is also
reported. The results obtained for different sensors indicate a
measured time resolution around 40–70 ps. Although particles are
expected to traverse only one SPAD per event, crosstalk measurements
on different sensors indicate an unexpected higher value with
respect to the one related to the sensor noise.
Predicting nitrate leaching loss in temperate rainfed cereal crops: relative importance of management and environmental drivers
Authors: Tamagno Santiago , Eagle Alison J , McLellan Eileen L , van Kessel Chris , Linquist Bruce A , Ladha Jagdish Kumar , Lundy Mark E , Pittelkow Cameron M
Published: June 2022

Nitrate (NO3) leaching from agriculture represents the primary source of groundwater contamination and freshwater ecosystem degradation. At the field level, NO3 leaching is highly variable due to interactions among soil, weather and crop management factors, but the relative effects of these drivers have not been quantified on a global scale. Using a global database of 82 field studies in temperate rainfed cereal crops with 961 observations, our objectives were to (a) quantify the relative importance of environmental and management variables to identify key leverage points for NO3 mitigation and (b) determine associated changes in crop productivity and potential tradeoffs for high and low NO3 loss scenarios. Machine learning algorithms (XGboost) and feature importance analysis showed that the amount and intensity of rainfall explained the most variability in NO3 leaching (up to 24 kg N ha−1), followed by nitrogen (N) fertilizer rate and crop N removal. In contrast, other soil and management variables such as soil texture, crop type, tillage and N source, timing and placement had less importance. To reduce N losses from global agriculture under changing weather and climatic conditions, these results highlight the need for better targeting and increased adoption of science-based, locally adapted management practices for improving N use efficiency. Future policy discussions should support this transition through different instruments while also promoting more advanced weather prediction analytics, especially in areas susceptible to extreme climatic variation.
The influence of local waste management culture on individual recycling behavior
Authors: Kountouris Yiannis
Published: June 2022

The transition towards sustainable consumption and production requires public engagement and support. In this context, understanding the determinants of individual pro-environmental behavior can assist in sustainability policy design, and contribute to explaining cross-country and regional differences in its implementation and effectiveness. This paper examines the influence of local waste management culture on individual recycling behavior. To isolate the impact of location-specific norms, habits and traditions comprising waste management culture from the confounding effect of contemporaneous local economic and social conditions, we use data from over 40 000 domestic immigrants in Greece. Estimating models relating individual recycling activity in the region of current residence to recycling practices in the region of origin, we find robust evidence that region of origin waste management practices have quantitatively and statistically significant influence on individual recycling behavior: a 10 percentage point increase in the prevalence of recycling in the region of origin, increases the probability a subject recycles by 0.9 percentage points. The results suggest that locally prevailing waste management norms and practices influence individual recycling behavior independently of local economic, social and environmental circumstances. Designing effective sustainability policy may need to account for regional variation in norms and preferences, and encourage investment in the development of sustainable waste management culture.
Stretched lignin/polyacrylonitrile blended carbon nanofiber as high conductive electrode in electric double layer capacitor
Authors: Kumar Manish , Taira Shogo , Pakkang Nutthira , Shigetomi Kengo , Uraki Yasumitsu
Published: June 2022

In this study, lignin-based conducting carbon nanofiber mat was prepared by electrospinning followed by a thermal treatment. Lignin is a sustainable carbon precursor. Polyacrylonitrile (PAN) acts as a binder polymer, which increases the viscosity of the lignin solution using dimethylformamide solvent and helps in the formation of a stable nanofiber. The mixture solution was electrospun, followed by stabilisation and carbonisation to yield carbon nanofibers (CNFs). A fixed amount of external load was provided to the lignin fiber mat during the stabilisation procedure and then carbonised to yield stretched carbon nanofibers (S-CNFs). On stretching the mat, surface conductivity was enhanced by 3 times, and the surface area by 1.3 times compared to that of non-stretched CNFs. Finally, the electric double layer capacitor (EDLC) was assembled with the resulting (CNFs and S-CNFs) nanofiber mat using 6 M of KOH aqueous solution. S-CNFs mat exhibits a specific capacitance of 266 F g−1, which was higher than that of CNFs, i.e. 258 F g−1 at a scan rate of 5 mVs−1 .
Enhanced relaxor behavior and high energy storage efficiency in niobium substituted (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 ceramics
Authors: P Vineetha , Jose Roshan , Vijay Ammu , S Charan Prasanth , K Venkata Saravanan
Published: June 2022

The microstructure, dielectric properties, relaxor behavior, and energy storage efficiency of un-substituted and niobium (Nb) substituted (Ba0.85 Ca0.15)(Zr0.1 Ti0.9) 1-x NbxO3 (for x = 0, 0.02 and 0.05) samples prepared by the solid-state reaction method has been studied in detail. All the samples exhibited perovskite structure with no trace of impurity. Composition-dependent phase transition was also observed on the addition of Niobium. At room temperature, the co-existence of rhombohedral and tetragonal phases is observed in the unsubstituted samples. As the composition changes from x = 0.02 to x = 0.05, a structural change from tetragonal to cubic is observed. A remarkable reduction in grain size, from 90 μm (for x = 0) to 1.21 μm for (x = 0.05), is observed with the addition of Niobium. This result suggests that Niobium acts as a grain growth inhibiter in barium calcium zirconium titanate (BCZT) ceramics. The effect of Niobium on transition temperature is studied from the temperature-dependent dielectric permittivity graph. It was clear that the transition temperature shifted to a lower temperature region, and for x = 0.05, at a very low temperature (−23 °C/250 K) the tetragonal to cubic transition was observed. At x = 0.05, the temperature-dependent dielectric permittivity showed a broadened curve, indicating a diffuse phase transition. The diffuse phase transition in Nb substituted samples is explained by Uchino and Nomura modified Curie Weiss law.

Moreover, the observations on temperature-dependent dielectric permittivity measurements at various frequencies suggest that the substitution of Nb5+ induces relaxor behavior. The energy storage efficiency of unsubstituted and Nb substituted samples was calculated from the polarization versus electric field graph. A high storage efficiency of 84% was obtained for the Nb substituted sample (x = 0.05) at 12 kV cm−1. Enhanced relaxor behavior and increased storage efficiency were observed in (Ba0.85 Ca0.15)(Zr0.1 Ti0.9) 1-x NbxO3 at x = 0.05. Thus we suggest that these are promising materials for energy storage applications.
Improved sensitivity on detection of Cu and Cr in liquids using glow discharge technology assisted with LIBS
Authors: SUN Duixiong , WANG Yarui , SU Maogen , HAN Weiwei , DONG Chenzhong
Published: June 2022

Laser-induced breakdown spectroscopy-assisted glow discharge (LIBS-GD) for analysis of elements in liquid was proposed, and it was applied to detect heavy metals in highly sensitive mixed solutions of Cu and Cr. During the experiments of GD and LIBS-GD, the experimental parameters have been optimized and the optimal voltage is 450 V, laser energy is 60 mJ, and the delay time is 4000 ns. Furthermore, the calibration curves of Cu and Cr under GD and LIBS-GD experiments have been established, and the limits of detection (LODs) of Cu and Cr were obtained with the method of GD and LIBS-GD, respectively. The LOD of Cu decreased from 3.37 (GD) to 0.16 mg l−1 (LIBS-GD), and Cr decreased from 3.15 to 0.34 mg l−1. The results prove that the capability of elemental detection under LIBS-GD has improved compared with the GD method. Therefore, LIBS-GD is expected to be developed into a highly sensitive method for sewage detection.
Investigation of a facile plasma-driven method for in situ cleaning of metal-based contamination
Authors: WANG 王 Sishu 思蜀 , YANG 杨 Li 黎 , PU 蒲 Guo 国 , LIU 刘 Jianxing 建星 , JING 荆 Wenna 文娜 , GOU 芶 Fujun 富均 , CHEN 陈 Shuwei 曙嵬 , CHEN 陈 Bo 波 , CHEN 陈 Jianjun 建军 , YE 叶 Zongbiao 宗标 , WEI 韦 Jianjun 建军
Published: June 2022

Self-cleaning of tin contaminants was realized utilizing a self-driven hydrogen plasma. Cleaning rates of 0.7–6 nm min−1 were achieved for removal of discontinuous tin particles at different powers. The analysis of topography and cross-sectional morphology revealed that the removal of tin particles was achieved through top-down cleaning with hydrogen plasma, where the upper part of spherical tin particles was always more intensely cleaned under the synergistic effect of hydrogen atoms and ions due to the vertical incidence of ions to the substrate during the whole cleaning process. Redeposition of tin atoms caused by physical sputtering and its promotion of the chemical cleaning effect was observed for the first time. Reflectance recovery measurements during cleaning and surface analysis of the substrate after cleaning indicated that nondestructive cleaning with a reflectance loss of less than 1% can be achieved at a relatively low power of 120 W. Plasma-induced substrate damage, such as holes and valleys, reduced the reflectance of the substrate when cleaning was performed at a high power greater than 120 W, so this method should only be considered for application under conditions without substrate exposure. This study provides a comprehensive understanding of the removal of discontinuous tin particles using the in situ self-driven plasma cleaning method, and also provides meaningful guidance for the extension of this method in other potential fields of application.
Asymptotic vanishing of syzygies of algebraic varieties
Authors: Park Jinhyung
Published: June 2022

The purpose of this paper is to prove Ein–Lazarsfeld’s conjecture on asymptotic vanishing of syzygies of algebraic varieties. This result, together with Ein–Lazarsfeld’s asymptotic nonvanishing theorem, describes the overall picture of asymptotic behaviors of the minimal free resolutions of the graded section rings of line bundles on a projective variety as the positivity of the line bundles grows. Previously, Raicu reduced the problem to the case of products of three projective spaces, and we resolve this case here.
4-Phenylbutyrate restored γ-aminobutyric acid uptake and reduced seizures in SLC6A1 patient variant-bearing cell and mouse models
Authors: Nwosu Gerald , Mermer Felicia , Flamm Carson , Poliquin Sarah , Shen Wangzhen , Rigsby Kathryn , Kang Jing Qiong
Published: June 2022

We have studied the molecular mechanisms of variants in solute carrier Family 6 Member 1 associated with neurodevelopmental disorders, including various epilepsy syndromes, autism and intellectual disability. Based on functional assays of solute carrier Family 6 Member 1 variants, we conclude that partial or complete loss of γ-amino butyric acid uptake due to reduced membrane γ-amino butyric acid transporter 1 trafficking is the primary aetiology. Importantly, we identified common patterns of the mutant γ-amino butyric acid transporter 1 protein trafficking from biogenesis, oligomerization, glycosylation and translocation to the cell membrane across variants in different cell types such as astrocytes and neurons. We hypothesize that therapeutic approaches to facilitate membrane trafficking would increase γ-amino butyric acid transporter 1 protein membrane expression and function. 4-Phenylbutyrate is a Food and Drug Administration-approved drug for paediatric use and is orally bioavailable. 4-Phenylbutyrate shows promise in the treatment of cystic fibrosis. The common cellular mechanisms shared by the mutant γ-amino butyric acid transporter 1 and cystic fibrosis transmembrane conductance regulator led us to hypothesize that 4-phenylbutyrate could be a potential treatment option for solute carrier Family 6 Member 1 mutations. We examined the impact of 4-phenylbutyrate across a library of variants in cell and knockin mouse models. Because γ-amino butyric acid transporter 1 is expressed in both neurons and astrocytes, and γ-amino butyric acid transporter 1 deficiency in astrocytes has been hypothesized to underlie seizure generation, we tested the effect of 4-phenylbutyrate in both neurons and astrocytes with a focus on astrocytes. We demonstrated existence of the mutant γ-amino butyric acid transporter 1 retaining wildtype γ-amino butyric acid transporter 1, suggesting the mutant protein causes aberrant protein oligomerization and trafficking. 4-Phenylbutyrate increased γ-amino butyric acid uptake in both mouse and human astrocytes and neurons bearing the variants. Importantly, 4-phenylbutyrate alone increased γ-amino butyric acid transporter 1 expression and suppressed spike wave discharges in heterozygous knockin mice. Although the mechanisms of action for 4-phenylbutyrate are still unclear, with multiple possibly being involved, it is likely that 4-phenylbutyrate can facilitate the forward trafficking of the wildtype γ-amino butyric acid transporter 1 regardless of rescuing the mutant γ-amino butyric acid transporter 1, thus increasing γ-amino butyric acid uptake. All patients with solute carrier Family 6 Member 1 variants are heterozygous and carry one wildtype allele, suggesting a great opportunity for treatment development leveraging wildtype protein trafficking. The study opens a novel avenue of treatment development for genetic epilepsy via drug repurposing.