bluuebunny/crossref_metadata_2025 huggingface dataset:
Continuous broadband microwave electric field measurement in Rydberg atoms based on the DC Stark effect
Authors: Ouyang Kang , Shi Yuansheng , Lei Mingwei , Shi Meng
Published: December 2023

We demonstrate a method for broadband tunable continuous frequency electric field measurement based on the DC Stark effect in Rydberg atoms. In our experiment, we place a pair of parallel electrode plates inside the atomic vapor cell, utilizing the DC Stark effect to induce splitting and shifting of the Rydberg energy levels, thereby altering the resonance frequency of the Stark subpeaks. By employing the 52D5/2 Rydberg state, we achieve electric field measurements in the frequency range of 5.083–14.470 GHz. At an EDC of 3.45 V/cm and a resonant microwave frequency of 14.470 GHz, using heterodyne technology, the microwave electric field sensitivity is 538.89 μV/cm/√Hz, with a linear dynamic range of 23 dB. In comparison, a Rydberg heterodyne receiver with an EDC of 0 V/cm and a resonant microwave frequency of 5.083 GHz has a sensitivity of 5.43 μV/cm/√Hz and a linear dynamic range of 51 dB. This work will promote the study of atomic microwave receivers in continuous microwave frequency measurement.
Growth of epitaxial (100)-oriented rare-earth nitrides on (100)LaAlO3
Authors: Anton E.-M. , Trewick E. , Holmes-Hewett W. F. , Chan J. R. , McNulty J. F. , Butler T. , Ruck B. J. , Natali F.
Published: December 2023

Epitaxial growth of (100)-oriented rare-earth nitrides (RENs) SmN, GdN, and DyN on (100)LaAlO3 (LAO) substrates is demonstrated using molecular beam epitaxy. RHEED and ϕ-scans confirm that the cubic RENs grow 45° rotated with respect to the pseudocubic (100)-surface of LAO, which leads to lattice mismatches between −5.8% and −8.7% for the selected RENs. Those lattice mismatches, despite being significant, are smaller than in previously reported epitaxial (100)RENs, with the exception of growth on (100)YSZ (yttria stabilized zirconia), which however causes the formation of an interface oxide layer. The SmN RHEED pattern shows intense streaks, indicating a high quality, flat surface, and the rocking curves are among the narrowest reported for (100)RENs. In contrast to growth on Si, the epitaxial RENs readily form over a wide range of substrate temperatures, without the need of special substrate treatment or intermediate layers. This robust, high quality growth paired with their clear magnetic switching behavior makes epitaxial RENs grown on LAO ideal candidates for future spintronic devices.
Heralded and robust W-state generation for distant superconducting qubits with practical microwave pulse scattering
Authors: Guo Zehui , Xie Zhihao , Wang Yimin , Li Zhenhua , Li Tao
Published: December 2023

Nonlocal multipartite entanglement holds significant potential for both fundamental physics and practical applications. We present a robust protocol for generating remote entanglement, specifically W states, among multiple nonlocal superconducting qubits. Our protocol employs practical microwave pulse scattering through a microwave cavity, which is coupled to a far-detuned superconducting transmon qubit, facilitating a CNOT-like operation. Our approach can be implemented without the need for single microwave-photon sources and its completion is heralded by microwave photon measurements. Furthermore, our protocol can generate faithful nonlocal W states of distant superconducting qubits with practical detector units, each cascading two quantum non-demolition detectors, rather than ideal single-photon detectors. These distinct features make our protocol particularly useful for large quantum secure communication networks.
Observed humidity trends in dry regions contradict climate models
Authors: Simpson Isla R. , McKinnon Karen A. , Kennedy Daniel , Lawrence David M. , Lehner Flavio , Seager Richard
Published: December 2023

Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas–driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor–holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward.
Multiscale drainage dynamics with Haines jumps monitored by stroboscopic 4D X-ray microscopy
Authors: Tekseth Kim Robert , Mirzaei Fazel , Lukic Bratislav , Chattopadhyay Basab , Breiby Dag Werner
Published: December 2023

Slow multiphase flow in porous media is intriguing because its underlying dynamics is almost deterministic, yet depends on a hierarchy of spatiotemporal processes. There has been great progress in the experimental study of such multiphase flows, but three-dimensional (3D) microscopy methods probing the pore-scale fluid dynamics with millisecond resolution have been lacking. Yet, it is precisely at these length and time scales that the crucial pore-filling events known as Haines jumps take place. Here, we report four-dimensional (4D) (3D + time) observations of multiphase flow in a consolidated porous medium as captured in situ by stroboscopic X-ray micro-tomography. With a total duration of 6.5 s and 2 kHz frame rate, our experiments provide unprecedented access to the multiscale liquid dynamics. Our tomography strategy relies on the fact that Haines jumps, although irregularly spaced in time, are almost deterministic, and therefore repeatable during imbibition-drainage cycling. We studied the time-dependent flow pattern in a porous medium consisting of sintered glass shards. Exploiting the repeatability, we could combine the radiographic projections recorded under different angles during successive cycles into a 3D movie, allowing us to reconstruct pore-scale events, such as Haines jumps, with a spatiotemporal resolution that is two orders of magnitude higher than was hitherto possible. This high resolution allows us to explore the detailed interfacial dynamics during drainage, including fluid-front displacements and velocities. Our experimental approach opens the way to the study of fast, yet deterministic mesoscopic processes also other than flow in porous media.
Disadvantaged group members are prouder of their group when using the language of the dominant group compared to their native language
Authors: Hasan-Aslih Siwar , Idan Orly , Willer Robb , Halperin Eran
Published: December 2023

In ethnically and linguistically diverse societies, disadvantaged groups often face pressures to acquire and speak the advantaged group’s language to achieve social inclusion and economic mobility. This work investigates how using the advantaged group’s language affects disadvantaged group members’ in-group pride and collective self-esteem, relative to using their native language. Across six experimental studies involving Palestinian citizens of Israel (total
N
= 1,348), we test two competing hypotheses: Disadvantaged group members may experience greater in-group pride when using a) their native language, due to its emotional significance (the
nativity hypothesis
), or b) the language of the advantaged group, due to activation of habituated compensatory responses to dominance relations (the
identity enhancement hypothesis
). We found that respondents reported significantly higher in-group pride when responding to a Hebrew survey when compared to performing the same activity in Arabic (Studies 1a and 1b), regardless of whether the researchers administering the survey were identified as Jewish or Arab (Studies 2a and 2b). Study 3 replicated this effect while employing the “bogus pipeline” technique, suggesting the pride expression was authentic, not merely driven by social desirability. Finally, Study 4 (pre-registered) examined additional measures of positive regard for the in-group, finding that participants described their group more positively in an attribute selection task, and reported greater collective self-esteem, when surveyed in Hebrew, rather than in Arabic. Taken together, these findings suggest that language use influences disadvantaged group members’ perceptions and feelings concerning their group when those languages are associated with relative position in an intergroup hierarchy.
Social anxiety disorder-associated gut microbiota increases social fear
Authors: Ritz Nathaniel L. , Brocka Marta , Butler Mary I. , Cowan Caitlin S. M. , Barrera-Bugueño Camila , Turkington Christopher J. R. , Draper Lorraine A. , Bastiaanssen Thomaz F. S. , Turpin Valentine , Morales Lorena , Campos David , Gheorghe Cassandra E. , Ratsika Anna , Sharma Virat , Golubeva Anna V. , Aburto Maria R. , Shkoporov Andrey N. , Moloney Gerard M. , Hill Colin , Clarke Gerard , Slattery David A. , Dinan Timothy G. , Cryan John F.
Published: December 2023

Social anxiety disorder (SAD) is a crippling psychiatric disorder characterized by intense fear or anxiety in social situations and their avoidance. However, the underlying biology of SAD is unclear and better treatments are needed. Recently, the gut microbiota has emerged as a key regulator of both brain and behaviour, especially those related to social function. Moreover, increasing data supports a role for immune function and oxytocin signalling in social responses. To investigate whether the gut microbiota plays a causal role in modulating behaviours relevant to SAD, we transplanted the microbiota from SAD patients, which was identified by 16S rRNA sequencing to be of a differential composition compared to healthy controls, to mice. Although the mice that received the SAD microbiota had normal behaviours across a battery of tests designed to assess depression and general anxiety-like behaviours, they had a specific heightened sensitivity to social fear, a model of SAD. This distinct heightened social fear response was coupled with changes in central and peripheral immune function and oxytocin expression in the bed nucleus of the stria terminalis. This work demonstrates an interkingdom basis for social fear responses and posits the microbiome as a potential therapeutic target for SAD.
ANGPTL4 binds to the leptin receptor to regulate ectopic bone formation
Authors: Hu Hongling , Luo Sheng , Lai Pinglin , Lai Mingqiang , Mao Linlin , Zhang Sheng , Jiang Yuanjun , Wen Jiaxin , Zhou Wu , Liu Xiaolin , Wang Liang , Huang Minjun , Hu Yanjun , Zhao Xiaoyang , Xia Laixin , Zhou Weijie , Jiang Yu , Zou Zhipeng , Liu Anling , Guo Bin , Bai Xiaochun
Published: December 2023

Leptin protein was thought to be unique to leptin receptor (LepR), but the phenotypes of mice with mutation in LepR [
db/db
(diabetes)] and leptin [
ob/ob
(obese)] are not identical, and the cause remains unclear. Here, we show that
db/db
, but not
ob/ob
, mice had defect in tenotomy-induced heterotopic ossification (HO), implicating alternative ligand(s) for LepR might be involved. Ligand screening revealed that ANGPTL4 (angiopoietin-like protein 4), a stress and fasting-induced factor, was elicited from brown adipose tissue after tenotomy, bound to LepR on PRRX1
+
mesenchymal cells at the HO site, thus promotes chondrogenesis and HO development. Disruption of LepR in PRRX1
+
cells, or lineage ablation of LepR
+
cells, or deletion of ANGPTL4 impeded chondrogenesis and HO in mice. Together, these findings identify ANGPTL4 as a ligand for LepR to regulate the formation of acquired HO.
Quafu-Qcover: Explore combinatorial optimization problems on cloud-based quantum computers
Authors: Xu 许 Hong-Ze 宏泽 , Zhuang 庄 Wei-Feng 伟峰 , Wang 王 Zheng-An 正安 , Huang 黄 Kai-Xuan 凯旋 , Shi 时 Yun-Hao 运豪 , Ma 马 Wei-Guo 卫国 , Li 李 Tian-Ming 天铭 , Chen 陈 Chi-Tong 驰通 , Xu 许 Kai 凯 , Feng 冯 Yu-Long 玉龙 , Liu 刘 Pei 培 , Chen 陈 Mo 墨 , Li 李 Shang-Shu 尚书 , Yang 杨 Zhi-Peng 智鹏 , Qian 钱 Chen 辰 , Jin 靳 Yu-Xin 羽欣 , Ma 马 Yun-Heng 运恒 , Xiao 肖 Xiao 骁 , Qian 钱 Peng 鹏 , Gu 顾 Yanwu 炎武 , Chai 柴 Xu-Dan 绪丹 , Pu 普 Ya-Nan 亚南 , Zhang 张 Yi-Peng 翼鹏 , Wei 魏 Shi-Jie 世杰 , Zeng 增 Jin-Feng 进峰 , Li 李 Hang 行 , Long 龙 Gui-Lu 桂鲁 , Jin 金 Yirong 贻荣 , Yu 于 Haifeng 海峰 , Fan 范 Heng 桁 , Liu 刘 Dong E. 东 , Hu 胡 Meng-Jun 孟军
Published: December 2023

We introduce Quafu-Qcover, an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends. Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm (QAOA). It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization (QUBO) model and its corresponding Ising model, which can be subsequently transformed into a weight graph. The core of Qcover relies on a graph decomposition-based classical algorithm, which efficiently derives the optimal parameters for the shallow QAOA circuit. Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers. Compared to a general-purpose compiler, our compiler demonstrates the ability to generate shorter circuit depths, while also exhibiting superior speed performance. Additionally, the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time, utilizing the most recent calibration data from the superconducting quantum devices. This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity. The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time, enabling asynchronous processing. Moreover, it incorporates modules for results preprocessing and visualization, facilitating an intuitive display of solutions for combinatorial optimization problems. We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers.
Techno-economic analysis of I-CAES systems to increase dispatchability of wind power
Authors: Cioni Stefano , Papini Claudio , Superchi Francesco , Milazzo Adriano , Bianchini Alessandro
Published: December 2023

The variability of energy production from renewable sources remains the main issue hampering their larger penetration in current energy grids. While batteries have been proven to work well in many applications, their cost and environmental footprint are opening room for alternative systems. In this study, the innovative isothermal compressed air energy storage (I-CAES) system proposed by Sadaat et al. in 2014 is analyzed. In this system layout, a wind turbine is coupled with a CAES system through a hydraulic circuit including a liquid piston. The original work theorized the system and focused only on a preliminary verification under an energy perspective, using data referring to very short time series. In the present study, a long-term techno-economic analysis is performed to provide a more representative insight into the real feasibility of the proposed plant configuration. The analysis is carried out using yearly wind speed data and a 1-minute average approach, so as to correctly track the energy fluxes. A parametric analysis of the system, varying the size of the storage vessel and generator is performed to identify the optimal configuration. Finally, the overall performance is compared with that of a traditional standalone turbine. The effect of fluctuations in the energy price during the day is considered, as well as the impact of possible future scenarios, where traditional systems are penalized due to significant oscillations in power production. Results show that, despite the high compression and expansion efficiencies achieved through the liquid piston, the complexity of the system causes a significant reduction of total energy production affecting the economic performance, although interesting prospects can arise whenever constant-load off-grid users are about to be fed.
Wave Energy Converters and Hydraulic Power Take-off: analysis of a possible control strategy
Authors: Barone Piofrancesco , Castiglione Teresa , Bova Sergio
Published: December 2023

Wave energy conversion is one of the most promising but untapped worldwide technologies. In fact, wave energy is clean and renewable as the solar and wind ones, but also less mature and utilized. Moreover, several Wave Energy Converters (WECs) patents have been developed in the last decades, as evidence of the great potential beneath these systems. Among the different issues related to this technology, the most challenging is controlling such systems. Maximizing the captured energy is indeed the main goal of a WEC’s control mechanism. As for single-mode oscillating absorbers, it has been proven that a resonance condition between body velocity and excitation force must be achieved. This control solution is generally called phase control. Different phase control strategies have been realized since the 1970s and latching control is one of them. However, how to implement sub-optimal phase control in real seas remains an open problem. A numerical model of the wave energy converter and its power take-off system is proposed in this paper. More precisely, the model simulates the hydrodynamics of a WEC point absorber coupled with a hydraulic Power Take Off in regular waves. Additionally, a parametric latching control strategy is suggested to enhance the converter’s power capture performance.
Ammonia as a Fuel for Gas Turbines: Perspectives and Challenges
Authors: Langella G. , Sorrentino G. , Sabia P. , Ariemma G. B. , Amoresano A. , Iodice P.
Published: December 2023

The paper addresses the prospects and challenges associated with the use of ammonia in gas turbine plants. The complexity of the chemical kinetic mechanisms of ammonia combustion and the insufficient amount of experimental data that can confirm the results still require a lot of scientific research. In this sense, this application is even less technologically mature than other sectors such as the marine engine one. From the point of view of combustion in gas turbines, the techniques in use and being perfected to deal with flame instability, low laminar burning velocity (about 20% of that of methane-air flames), the long ignition delay time and low volumetric heat release rate. In particular, the use of ammonia blended with other combustion enhancers such as hydrogen, methane and alcohols has been analyzed. Mild combustion is also being analyzed as a valid technique for dealing with the difficulties of ammonia combustion. The combustion of ammonia generates significant quantities of nitrogen oxides, both for the thermal mechanism and for the “fuel” one, which must therefore be mitigated, together with the emission of unburnt ammonia. Even in this case, blending with other fuels allows for improved emissions performance. The paper compares the different techniques and the relative advantages both in terms of combustion efficiency and emissions. Finally, the perspectives for the use of ammonia in gas turbines are outlined, highlighting the challenges still to be overcome, in a panorama of energy transition towards an increasingly decarbonized future, with the aim of mitigating climate change as much as possible.
Battery–integrated combined cooling, heating and power plant (CCHP) through NH3 – H2O absorption system in a hospital facility
Authors: Simone Braccio , Alfredo Gimelli , Raffaele Iossa , Alì Karimi , Massimiliano Muccillo , Trieu Phan Hai
Published: December 2023

Combined heat and power (CHP) systems have been employed in various applications for years. They are gaining increasing attention in the residential and small industrial sectors for their primary energy saving potential and CO
2 emissions reduction. Additionally, in specific applications such as the hospital sector, CHP plants can play a critical role in replacing fossil-fueled electric generators to supply electricity during local grid outages, thus enhancing hospital facilities’ energy efficiency, while also securing reliability and efficiency of operation. Hospitals have unique energy demand profiles, with high and constant demand (particularly heating and cooling demands), making them an ideal use-case for trigeneration systems. Combined, cooling, heating and power plants (CCHP) are capable to provide not only heating and electricity, but also cooling through the efficient exploitation of a single energy source, reducing Hospitals’ reliance on the local grid. In this context, this work aims at evaluating the potential of a battery-integrated CCHP plant through an innovative ammonia-water absorption system, whose energy analysis is based on data acquired from an Italian Hospital facility. The potential of integrating an experimental combined cooling and power production ammonia-water absorption system has been investigated starting from an optimized battery energy storage system (BESS) CHP plant configuration, studied for the same facility. A proper control strategy has been developed to maximize the cooling production when required from the end-user through CHP plant’s exhaust gases waste heat recovery. The energy analysis demonstrated the advantages of the CCHP-BESS plant over the optimal CHP-BESS configuration, with an 11.22% increase in primary energy saving, a 9.85% reduction in CO
2 emissions, and a 5.03% decrease in electric peak power demand.
Green hydrogen production in a south of Italy region using excess electricity only: real scenario and alternatives
Authors: Caramia Giovanni , Amirante Riccardo
Published: December 2023

Stating the European Union decarbonisation objectives setting carbon neutrality by 2050, this article proposes a thorough analysis of alternative energy system scenarios deriving firstly from the hypothetical switch-off of a coal-fired power plant, secondly from the the contextual introduction of Hydrogen Valleys’ electrolysers, thirdly from the increase in the peak photovoltaic power matching the switched-off power plant annual energy production. Hydrogen generation, carbon dioxide and excess electricity production as well as grid stabilization are the main investigated aspects. After a brief description of the methodology based on the use of the freeware EnergyPLAN model, authors describe the reference as well as alternative considered scenarios. Main results obtained start from annual CO2 emission and power plant production analysis continuing with the description of electrical grid demand/production imbalance arising if a variable renewable energy source higher production level is introduced. The role of electricity storage thought as the coupling of electrolyser and hydrogen fired gas turbine is then investigated. The total hydrogen production potential based on the use of the solely excess electricity production is determined. The mean monthly power plant, renewable sources and total productions are compared with the demand curve arguing that power plants mostly contributes to the shape of production curve whereas renewable energy sources contribute to increase the total production level so to reach the actual demand values. Lastly, a grid stability constraints analysis ends the proposed results.
A model-based approach to long-term energy planning: the case-study of the Turin Airport
Authors: Prussi M. , Laveneziana L. , Misul D. , Chiaramonti D. , Odisio M. , Restaldo G.
Published: December 2023

Urged by the concerns relating to climate change and the energy crises, several companies and industries have been undertaking a deeply transformation of their energy system. Energy planning, especially with a long-term perspective, has assumed a renewed importance. The traditional approaches about energy planning, typically relying on a single-project analyses and a short-term vision, appear today unsuitable for evaluating the disruptive transformation of the energy system. In this paper, we propose an energy system optimization approach, based on a detailed energy planning, and we discuss its application to an energy intensive industry: airports. In the context of the European TULIPS project, the energy system of the fellow airport of Turin was modelled in the open-source OSeMOSYS framework. The model was then validated on a set of reference years of operation of the airport. The results of the modelling exercise showed minor variations with respect to real-world data, with a percent error well below 2.5%. Having assessed the ability of the model to reproduce the behavior of the energy system, future studies will be devoted to the development of a decarbonisation roadmap for Turin Airport.
Improving energy efficiency and Indoor Environmental Quality in the School of Mathematics at the Sapienza University campus in Rome
Authors: Romano G , Rosso M , Mancini F , Salvo S
Published: December 2023

SDG 7 “affordable and clean energy” aims at expanding infrastructure and upgrading technology to provide clean and more efficient energy in all countries, encouraging socio-economic growth and helping the environment. Its implementation through legislative instruments led to the writing of the Sapienza Energy Plan and the Energy Implementation Program, which define a series of medium-term implementation strategies on buildings inside and outside the Sapienza University campus. Strategies aimed at the energy redevelopment of the building envelope to achieve the minimization of energy needs and the construction of PV systems as well as the technical and regulatory adaptation of existing HVAC systems to improve the environmental comfort conditions. By the requirements of current legislation, the Energy Performance has been quantified through the energy efficiency analysis of the building in its current state and post-interventions, led using a simulation on an energy diagnostic software. After the analyses, the refurbishment interventions have allowed defining the guidelines, in compliance with the contents of the Guidelines for the energy efficiency of cultural heritage and the PES, through a series of strategies aimed at the conservation and improvement of the building envelope and at improving the energy efficiency and the IEQ of the School of Mathematics.
Numerical modeling and exergetic analysis of efficiency improving solutions for a micro-CAES system
Authors: Tumminello D. , Bacci T. , Facchini B. , Stortiero F , Castelli G
Published: December 2023

The development of cost-effective energy storage systems with low environmental impact is crucial for the energy transition to enable the widespread use of renewable energy sources. Within this context, there is an increasing interest in Compressed Air Energy Storage (CAES), especially for its potential application in small-scale off-grid systems. In this study, a numerical model of a micro-CAES system for off-grid applications, with an output power of 5kW, is developed; the open source, object-oriented software OpenModelica is used and the model is validated by comparison with available experimental data. Following the validation, the model is used to identify the main exergetic losses and a series of efficiency enhancing solutions are evaluated, using the round-trip efficiency as an indicator. The study allows to identify the main technical aspects to focus on, in ordedr to improve the system, as well as the limit performance that the adopted CAES concept would allow to achieve.
Experimental analysis of a graphene oxide-enhanced paraffin PCM
Authors: Emmi G , Baccega E , Cesari S , Giacon L , Zarrella A , Bottarelli M
Published: December 2023

The research here presented aims at characterizing the thermal behaviour of a PCM-based latent heat storage enhanced with graphene oxide. The heat storage tank is composed of two PVC coaxial cylinders and a smooth stainless-steel helical heat exchanger installed inside the smaller one. The heat exchanger is immersed in PCM, a commercial paraffin with a melting temperature of around 28°C. The melting and solidification of the PCM were forced through hot or cold water flowing in the heat exchanger. The purpose is to explore the melting and solidification process by monitoring the temperature in the PCM with multiple thermocouples placed at different heights and different radial distances from the centre of the heat exchanger. Initially, the system was studied with pure paraffin. Then, two different mass percentages (i.e., 1.5% and 3%) of graphene oxide were added, whose high thermal conductivity had to counterbalance the paraffin low thermal conductivity and thus enhance the overall performance of the system. These three configurations were then compared to a reference scenario, consisting of the inner cylinder filled with pure water. The use of graphene oxide has increased the heat flux by up to 24% during heating and up to 31% during cooling compared to the pure PCM.
Digital Hydraulic Technology: Applications, Challenges, and Future Direction
Authors: Sciatti Francesco , Tamburrano Paolo , Distaso Elia , Amirante Riccardo
Published: December 2023

Digital hydraulic technology has emerged as a promising alternative to conventional hydraulic systems, offering several advantages such as improved energy efficiency, more precise control, and reduced complexity. In recent years, digital hydraulic technology applications have been widely researched in various engineering sectors, including aerospace, biomedical and industrial. The aim of this paper is to provide an overview of the recent advancements in digital hydraulic technology, focusing on the various applications and their benefits. The paper begins by introducing the two different branches of this innovative technology. Subsequently, it presents an overview of digital hydraulic technology applications, highlighting their specific advantages, particularly in biomedical, industrial and aeronautical sectors, when compared to conventional hydraulic technology. Finally, the paper addresses the challenges and limitations associated with digital hydraulic technology and discusses potential areas for future research and development.
Numerical Modeling and Simulation of a Small-Scale Locomotive Powered by Solid Oxide Fuel Cells
Authors: Kaya Ahmet Fatih , Pedrazzi Simone , Muscio Alberto
Published: December 2023

The adverse environmental effects of fossil fuels resulted in a sharp rise in demand for renewable energy sources such as solar, wind, and hydrogen. Environmental pollution might be drastically reduced by using renewable energy sources. Various examples of solid oxide fuel cells being employed in locomotives exist in the literature. This work used numerical techniques to simulate and model a vehicle with eight wheels, considered as a small-scale locomotive powered by solid oxide fuel cells. The feasibility of solid oxide fuel cell-based locomotive was investigated through numerical modeling and simulation. The Matlab-Simulink platform, which includes an electrical system, an energy management system, and vehicle dynamics, was used to run the simulations. Four different locomotive configurations were created, (1) The mass of the locomotive (m) = 65000 kg, operating temperature (T) = 750°C, (2) m = 65000 kg, T = 1000°C, (3) m = 80000 kg, T = 750°C, and (4) m = 80000 kg and T = 1000°C. The performance parameters of the vehicle were recorded after the simulations. These factors are crucial for optimizing the locomotives’ design and operation since they provide light on their performance. Future locomotive design and operation may be influenced by the findings of this study, resulting in more environmentally friendly and sustainable transportation networks.
Metal hydrides in hydrogen storage: optimization of dynamic control strategies
Authors: Jin Lingkang , Rossi Mosè , Caresana Flavio , Pelagalli Leonardo , Comodi Gabriele
Published: December 2023

Metal hydrides have emerged as a promising solution for efficient hydrogen storage in solid matter. While the charging and discharging kinetics of these systems are well-known, dynamic control strategies from a system’s perspective still need a detailed analysis by the scientific community. In this research work, a metal hydrides system and its dynamic controls have been numerically studied. AB2-type metals (ZrMn2) are involved as a storage medium, which is coupled to a conditioning system via a heat pump and a hydrogen compressor; therefore, both operating temperature and pressure can be controlled. Results showed that hydrogen pressure is a fundamental component in accelerating reaction dynamics and increasing stored mass. However, it is also the most energy-intensive component. The use of a conditioning system, which works at a proper set temperature, can reduce the hydrogen compressor energy to achieve the same performance, although requiring higher power input from the heat pump’s compressor. Furthermore, the operational strategy must be chosen based on either the minimization of charging/discharging time or energy expenses.
Environmental and Economic Assessment of the Italian Energy Transition Scenarios
Authors: Sorce Alessandro , Vannoni Alberto , Bellotti Daria , Rivarolo Massimo
Published: December 2023

The aim of this work is to assess the environmental and economic impact of the Energy Transition of the Italian Electrical Sector, as planned by the PNIEC (Integrated National Energy and Climate Plan), published in December 2019, and by the scenarios, developed by Terna and Snam, updated to reach the Fit-for-55 objectives. The analysis of the historical trends related to RES (Renewable Energy Sources) capacity increase, allows comparing the historical effort with the one expected to reach the 2030 goals. In particular wind off-shore production is expected to have a larger impact than envisaged before. On the technical side, some scenarios assumptions are going to be revised to more realistic values. The technological and economic efforts, besides an estimation of the expected global environmental benefit, are assessed taking into account: i) the revised RES capacity increase, ii) the grid infrastructure enhancement, and iii) the envisaged installation of new storage and electrolyzer capacity. With flexibility items, ii) and iii), requiring a similar level of capital cost as the new RES capacity. The reduction in natural gas consumption in the different scenarios is expected to reduce both the Green House Gas emissions and the operating cost with a large impact on the average efficiency of the natural gas-fed power plants.
Urban High-density 3D Ambient Noise Refracted Wave Extraction
Authors: Hu Ketong , Zhao Shuai
Published: December 2023

Active-source seismic detection is trapped in complex urban environmental noise and dense housing facilities, so this method is not suitable for urban environment, but the ambient noise method can obtain urban underground medium information at low cost and environmental protection. At the same time, in order to have a more comprehensive understanding of the underground situation, it is necessary to conduct three-dimensional detection of underground structures, arrange three-dimensional measurement lines, and high-density spatial sampling can obtain high-resolution detection results. In terms of ambient noise body wave extraction, the extraction of refracted waves is easier. Therefore, in this experiment, high-density 3D ambient noise refracted wave extraction is carried out for urban environment. In this paper, the refracted wave signal is extracted by cross-correlation of the collected 20-day ambient noise data.
Application of Ground Penetrating Radar and High Density Seismic Mapping Method in Tunnel Concrete Lining Detection
Authors: Xu Dexin , Yuan MuLin , Chen Xin , Guo Qi
Published: December 2023

If there are quality defects such as voids, non-compactness, insufficient lining thickness, and water-filled voids in the concrete structure, the bearing capacity and durability of the tunnel concrete lining structure will inevitably be affected. The non-destructive testing of tunnel concrete is a problem that the engineering community generally pays attention to, and it is the key to ensure the safe operation of tunnel concrete structures. Combined with engineering examples, the principle and method of using ground penetrating radar method and high-density seismic imaging method to detect internal defects of concrete are expounded, and the process of data processing is briefly introduced. The results are consistent, indicating the accuracy and feasibility of the ground penetrating radar method combined with the high-density seismic imaging method to detect the internal defects of tunnel concrete.
An Efficient Parallel Iterative Solver for Controlled-source Electromagnetic 3-D Adaptive Forward Modeling in General Anisotropic Media
Authors: Liu Zhengguang , Ren Zhengyong , Yao Hongbo , Tang Jingtian
Published: December 2023

Controlled-source electromagnetic (CSEM) surveys are moving increasingly toward realistic and complicated scenarios where the survey region may contain undulated topography, complex geometries, and electrical anisotropy media. In this paper, the adaptive finite element numerical method is employed to discrete the total electric field equation, which can provide precise electromagnetic (EM) responses even with a coarse initial mesh. The unstructured tetrahedral grid is employed to effectively address arbitrary irregular geometry and mountain terrain. Then, the flexible generalized minimum residual solver (FGMRES), auxiliary-space Maxwell pre-conditioner, and grid division technique were used to solve the large-scale linear system of equations, which can stably solve ill-conditioned problems using fewer computing resources. Finally, we conducted a numerical experiment via our newly proposed forward modeling scheme on a synthetic model with multi-contrast electrical anisotropy. It validated that accurate EM fields could be obtained against the semi-analytic solutions, and this iterative solver has good robustness for various anisotropic media. As a result, we have developed a state-of-the-art 3D CSEM anisotropic forward modeling engine, which can quickly and accurately deal with large-scale and complex geo-models.
On the Surface Waves Retrieved from High-speed Trains Running on Viaducts and Ground Surface
Authors: You Baiyang , Xia Jianghai , Mi Binbin , Liu Ya , Zhang Hao
Published: December 2023

The high-speed train (HST) generates strong ground vibrations when it runs on the railroad. However, little attention has been paid to retrieving surface wave from these vibrations. Here, we try to retrieve surface waves from HST-induced vibrations using field data. There are two kinds of HST tracks, one is built on the viaduct and the other is built on the ground. We acquired the signals generated by the HST running on the two kinds of tracks in Huzhou, China. In the original noise records, the HST signals can be obviously observed. In terms of a single HST event, the signals generated by the HST on the ground surface decay quickly and the signals generated by the HST running on the viaduct have broadband energy. We calculated the noise crosscorrelations in the HST-induced segments and stacked the results. Surface-wave dispersion energy were generated and compared with the results from the segments without HST. A significant improvement of the retrieval of surface waves were observed with signals generated by the HST running on viaducts while less obviously when on the ground surface.
Analysis of GPR Data Characteristics of Drainage Pipe and Cavity Coexisting
Authors: Ling Jianyu , Qian Rongyi
Published: December 2023

Drainage pipe leakage usually causes roadbed loosening and even collapse. Therefore it is of great significance to accurately locate and repair the leakage area. This paper studies the use of GPR to carry out the detection of drainage pipe leakage area, aiming to solve the problem of unclear electromagnetic wave field response characteristics when drainage pipes and cavities coexist. First, we used gprMax to carry out numerical simulation experiments to obtain the electromagnetic wave field response characteristics when a square cavity exists around a circular drainage pipe. Subsequently, similar data characteristics to the numerical simulation were obtained through field detection, and the area was confirmed to be a cavity caused by drainage pipe leakage through drilling. This study shows that the use of numerical simulations can provide a basis for the identification of cavities caused by drainage pipe leakage in GPR data.
Estimation of Soil Moisture Content of Farmlands Based on AEA Method of GPR
Authors: Liu Kexin , Lu Qi , Zeng Zhaofa , Li Zhilian
Published: December 2023

We used ground penetrating radar (GPR) to estimate the soil moisture content and its spatial distribution of farmland under different tillage modes in this paper. GPR data are collected on the farmlands with no-tillage (NT) and deep ploughing (DP), respectively. The average envelope amplitude (AEA) of GPR signal is used to estimate the soil moisture content which is constrained by time domain reflectometry (TDR) measurement. The findings of the field test indicate that the error of the moisture content obtained by AEA method is in a reasonable range. In the shallow layer of farmland, the AEA method of GPR for detecting the soil moisture content is feasible and different tillage modes can affect the change of soil moisture content.
Design and Development of A New GPR System for Soil Detection
Authors: Li Zhilian , Zeng Zhaofa , Li Risheng , Lu Qi , Xia Longfei , Wu Qiong , Liu Kexin , Wang Kuiwen , Yan Jiahe
Published: December 2023

Soil is a key factor in many fields such as national food security and ecological environment construction. In recent years, as an important geophysical method, ground penetrating radar (GPR) is widely used in soil detection. However, the detection efficiency and data quality of some GPR devices need to be improved in complex surface environments. In this paper, a new soil-special GPR device is designed. This device adopts a new antenna with strong directivity and high resolution. The corresponding data acquisition software is developed by Labview. Combined with GPS system, the acquisition trajectory is located with 1 cm accuracy. Compared with the MALA GPR device, the new soil-special GPR device has achieved high resolution detection results.
Three Dimension Ground Penetrating Radar and Data Processing for Pavement Collapse Detection
Authors: Tian Sen , Liu Sixin
Published: December 2023

Ground-penetrating radar (GPR) is a non-destructive testing exploration technology with the advantages of high efficiency and high resolution, and is widely used in roadbed detection and disease detection. With the increasing demand for road detection, traditional handheld two-dimensional GPR detection instruments can no longer meet the normal urban road detection requirements. Therefore, new efficient vehicle-mounted three-dimensional GPR systems have emerged and been put into use. This article mainly introduces some three-dimensional GPR instruments and systems that have been put into use, analyzes their composition structure, usage characteristics, compares their similarities and differences, and data processing methods, which can provide a certain reference for the forward simulation and data processing of three-dimensional GPR.
Experimental Validation of Enhanced GPR Signals by A Broadband Metasurface
Authors: Zheng Wuan , Hao Tong
Published: December 2023

In this paper, the potential of a broadband metasurface for ground penetrating radar (GPR) signal enhancement is investigated by simulation and experiments. Simulation results show that the reflection at the air-MUT interface can be reduced from 35% to 5% over a broad frequency range (relative bandwidth up to 44%) when the broadband metasurface is in place. Measured reflectance is consistent with the simulation results. Meanwhile, the electric field strength measurement results demonstrate that the transmitted electromagnetic signals can be amplified when the reflection is reduced over the same frequency range. GPR experiments verified that clear hyperbolic signals emerged for commonly undetectable pipes when the high-frequency signals are enhanced. The proposed broadband metasurface can be an effective solution for the detection of nonmetallic inclusions in high-lossy media.
Forward Modeling of Ground Penetrating Radar (GPR) Data with The COMSOL RF Module
Authors: Li Yuteng , Jiang Bici , Fan Tao , Liu Lei , Tian Xiaochao , Fang Zhe
Published: December 2023

COMSOL Multiphysics is one of the most popular multi-physics numerical calculation software. The forward modeling of GPR is realized based on COMSOL RF module, and the layered strata are simulated and verified by using Rake wavelet with center frequency of 400 MHz. The results show that the numerical simulation method of GPR established by COMSOL RF module has high calculation accuracy, which is helpful to study the propagation law of electromagnetic waves.
Multi-component Seismic Data Random Noise Attenuation via Quaternion Wavelet Transform
Authors: Li Fan , Gao Jianjun , Wang Yun , Chen Haifeng
Published: December 2023

In this paper, we present a new method with quaternion wavelet transform (QWT) to suppress the random noise of multi-component seismic data simultaneously. The proposed method could preserve the vector nature of the wavefield compared with the traditional wavelet threshold denoising approaches. Artificial data are used to test the new method’s performance. The experimental results show that QWT gets higher SNRs and better preserves weak reflecting energy.
Fast 3D Magnetotelluric Forward Modeling Based on a Regularization Approach in Spherical Coordinate
Authors: Wang Yongfei , Liu Jianxin , Guo Rongwen , Tian Shengqi , Li Jian
Published: December 2023

The earth’s curvature shouldn’t be ignored for the large-scale magnetotelluric (MT) modeling. A forward code of spherical coordinate MT method based on staggered grid finite difference method is developed. In addition, the forward problem is usually solved numerically, mostly based on iterative solution. Krylov subspace method is widely used to solve electromagnetic forward modeling problems in frequency domain. However, as the period increases, the convergence of these methods becomes significantly slower (especially for long-period MT data). We added a scaled grad-div operator to the double curl equation of the electric field to perform the nondivergence condition (CCGD). The results show that CCGD method is more efficient than other methods, which is an efficient method for our code.
Application of Impact Elastic Wave Method in Quality Inspection of Concrete Lining
Authors: Hu Xinmin , Wang Yanlong , Zhang Guoqiang , Du Lizhi
Published: December 2023

As the main part of inter-basin water transfer project, water tunnel plays an important role in long-distance water conveyance. In water tunnel, the lining quality problem is one of the important potential safety hazards of the tunnel engineering. It is very necessary to detect the internal defects of concrete lining. In this paper, a multi-parameter comprehensive interpretation method based on impact elastic wave is proposed to quickly detect the internal defects of lining. The common offset time domain analysis method, frequency domain analysis method and two-dimension Rayleigh wave method are used for data processing. The detection method has the characteristics of single data acquisition and multi-parameter joint interpretation. The physical model of concrete lining is tested and compared with the result of GPR method to verify the accuracy of this method. The coring results show the reliability and stability of this method in practical application.