bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability analysis of the impact of thickness measurement accuracy on the longitudinal strength assessment of CAP
Authors: Zhang Qingyue , Jiang Xueyun
Published: May 2024

The reliability analysis of the longitudinal bending strength of ships is conducted using the total probability method, taking into account and analyzing the accuracy error in thickness measurement of transverse section members on existing servicing ships. A mathematical model for calculating failure probability CAP ratings is established. By calculating the CAP rating of an aged LPG carrier, it is observed that when the deterministic method reaches the target rating, the failure probability in rating calculation by the reliability analysis method is high. This indicates a significant influence of thickness measurement accuracy on CAP rating accuracy.
Performance evaluation of Internet medical service based on network big data--Take Good Doctor Online as an example
Authors: Du Meijie , Yang Qian , Fan Linxi , Leng Yuxin
Published: May 2024

In order to develop new economic and social forms in a wide range, China has been actively promoting the ‘Internet +’ action to encourage the deep integration of the Internet and various fields. However, the performance of the Internet platform built in various fields has always been a difficulty in assessment and evaluation. Taking the ‘Internet + Medical’ Good Doctor Online platform as an example, this paper explores how the ‘Internet +’ platform conducts data collection, data cleaning, data conversion, data regulations and data visualization, thus exploring a general approach for the performance evaluation of the ‘Internet +’ platform. Based on this performance evaluation approach, this paper thinks that the performance of Good Doctor Online platform is good, but in order to promote the comprehensive development of Internet medical service, there are still some possibilities of improvement, such as standardization of subject classification, reasonableness of doctors resources distribution in different areas, sustainability of health insurance settlement and satisfaction enhancement, etc.
Eliturbo Air-Mixer: CFD Modelling of a Technology for the Reduction of Thermal Stratification in Large Spaces
Authors: Polito Antonio , Misté Gianluigi A. , De Betta Stefano , Campolmi Paolo
Published: May 2024

In the air conditioning of medium and large spaces, particularly in artisanal and industrial environments, characterized by heights well exceeding 4 meters, vertical air stratification during the heating phase is a common and undesirable phenomenon. Due to logistical reasons, it is not always possible to adopt heat distribution terminals optimally, prioritizing, for example, areas occupied by personnel to ensure thermal comfort or, in some cases, areas with machinery or other equipment that need to operate at specific temperatures. In the present paper the Eliturbo mixing system is presented along with a CFD study that illustrates the effects of introducing a destratification device inside a typical warehouse working environment.
Technical-economic and financial feasibility of new technologies in the energy refurbishment of residential buildings
Authors: Iunco Alberto , Paduos Simona , Chiappero Marco , Corrado Vincenzo , Santarelli Massimo
Published: May 2024

The revision of the Energy Performance of Building Directive (EPBD) provides for the construction of zero-emission buildings. The present work investigates possible solutions aimed at phasing out fossil fuel systems in buildings, in accordance with the EPBD requirements. An insulated residential building located in Rome is presented. The proposed refurbishment approach is based on the heating system replacement (heat pump, hydrogen fuel cell, hydrogen-ready boiler), and the use of renewable energy produced by a photovoltaic system. The results show that, although the energy optimal solution consists of the replacement of the heat plant with a heat pump coupled to both a PV and a fuel cell system, from the economicfinancial point of view the proven solution of heat pump coupled with PV is still the only feasible one.
Emerging technologies for air cleaning and their integration in HVAC systems: Which role in the increasing quest for healthy and sustainable buildings?
Authors: Joppolo Cesare Maria , Gandini Jacques
Published: May 2024

The paper starts from the consideration of both the fundamental goals of getting healthier indoor environments and at the same time obtaining much higher building energy efficiencies. In this frame, it presents a review of the different electrically connected technologies for Air Cleaning that are proposed for integration in HVAC Systems and gives a brief description of the air-cleaning options, of the applied mechanism and of the target pollutants. Thereafter the functions attributed to the air-cleaning components (i.e. control of indoor pollutant sources and/or cleaning of outdoor fresh air) are classified in order to clarify the rationale behind the organizing principle of the HVAC system. The paper concludes by giving information on the status of standards regarding performance and safety requirements.
CO2 emission reduction, loads analysis, and strategies for new healthcare facilities design – Application on a case study
Authors: Mantua Francesco , Turco Margherita , Bo Elena , Ferrara Maria , Rossi Prodi Fabrizio
Published: May 2024

To understand the “Zero Emission Building” goal introduced by the Energy Performance of Buildings Directive (EPBD) revision, it is certainly important to define its scope, since different considerations must be made for buildings with different uses, characteristics and locations. In this paper, the case study of a new construction hospital building is analysed, bringing attention to two main aspects: the correct identification of energy needs of the Heating, Ventilation and Air Conditioning (HVAC) systems; Mechanical, Electrical and Plumbing (MEP) design strategies aimed at minimizing CO2 emissions. To pursue these objectives, the hourly trends of energy consumption are examined, focusing on the interpretation of their distribution, the main influencing variables and on the distribution of such energy consumption among the different utilities of the analysed system. It is opinion of the authors that this in-depth study is preparatory to the proper MEP design of the systems: in fact, by knowing the most energyconsuming users and the distribution of heating and cooling loads during the year, it is possible to identify the optimal design strategies and generation technologies to reduce the consumption of Primary Non-Renewable Energy. In this regard, the choice of an ap-propriate calculation model is highlighted as crucial. Possible design strategies related to the case study under consideration are analysed in this paper, ultimately exposing the general considerations regarding the ZEB issue in the hospital setting.
Mixed-use neighbourhood to maximise urban energy community potential
Authors: Vecchi Francesca , Berardi Umberto
Published: May 2024

Renewable energy communities (REC) are key drivers in promoting energy transition to renewable energy sources (RES). To maximise local potential for RECs, matching demand and local production requires the integration of different load profiles. Residential users prevail in urban areas while planning mixed-use neighbourhoods would contribute to having complementary loads towards urban RECs. Mixed areas can optimise the use of renewable production at different hours and limit demand pressures on the network. However, detailed spatial analyses are required to cluster building functions for long-term benefits. This work investigates which mix of building functions in urban blocks can maximise energy self-consumption and self-sufficiency. Five blocks combining residential with productive and tertiary activities are chosen, from a completely residential to a heterogeneous mix. The single loads use representative buildings for the Italian context. The integration of building functions flattens the energy peak loads in the district while increasing the use of PV production. The study identifies the residential and non-residential ratios to maximise energy selfconsumption and self-sufficiency. Domestic users would mainly exploit the production from nearby non-domestic buildings, but adequate exchange mechanisms and upgrade of infrastructure still need to be implemented.
Exploiting geographic open data to improve urban building energy simulations: The Padova city center case study
Authors: Khajedehi Mohamad Hasan , Prataviera Enrico , Bordignon Sara , De Carli Michele
Published: May 2024

In recent years, building stock models have been developed by researchers to examine the aggregate performance of stacks of buildings within large areas, thereby giving rise to the concept of urban building energy models (UBEMs). The input data for such models consists of geometric and non-geometric attributes of the buildings, in addition to meteorological information. In this perspective, the acquisition of precise and comprehensive data poses a challenge, as the existing datasets often lack certain parameters or are not in a standardized format. This study aims to address the challenges by proposing a workflow for generating an input data frame tailored for incorporation into UBEMs. The data frame should include all the essential parameters of the buildings, and its constitution should be reflective of the real-world data. Moreover, the proposed workflow should remain consistent with databases available at national or regional levels. Acknowledging this non-uniformity in databases across regions, the methodology proposed in this study strategically considers various alternatives. For this reason, the proposed automatized workflow ensures flexibility and adaptability to changes in data availability. The workflow proposed in this study is a QGIS based geographical calculation method. The method can combine data from various sources into one shapefile that can be used to simulate the energy performance of buildings in urban areas.
UVC-Mirror for effective pathogens inactivation in air ducts
Authors: Treccani Laura , Rovetta Daniele , Zanetti Gabriele , Gobbi Emanuela , Turina Massimo , Lombini Matteo , Cortecchia Fausto , Diolaiti Emiliano , Malaguti Giuseppe , Bianco Andrea , Pareschi Giovanni , Mongelluzzo Giuseppe , Lessio Luigi
Published: May 2024

Improving the air quality of indoor environments (IAQ) is of utmost importance to safeguard public health as people spend about 80–90% of their time indoor. Efficient Ultraviolet germicidal irradiation (UVGI) system represents a strategic and sustainable solution to protect from recurrent and new airborne pathogens. Here, we present a new approach to design highly efficient UVGI systems, which can be installed in existing Air Treatment Units (ATU) plants with minimal effort. The increased efficiency relies on the concept of an optical cavity, thanks to its shape and source position. The internal volume consists of a highly reflective cavity illuminated with UV-C lamps. Optical simulations permitted the variation of the parameters to maximize the internal irradiance and, thus, the performance. The sanitation efficacy of the system was assessed on a full-scale pilot system. Tests were carried out under normal operating conditions against various microorganisms showed an inactivation rate of > 99%. The benefits of such systems are triple and encompass economic, environmental, and societal aspects. Since the system requires little energy to operate, its application for air disinfection may yield significant energy savings and ensure a balance between energy sustainability and good IAQ.
Liquid air filtration and continuous monitoring: Customized indoor air quality
Authors: Capulli Domenico , Regazzi Rogério
Published: May 2024

Air treatment in environmental air conditioning systems exposes the system to gases, contaminants, and often biological pollutants that cannot be solved by traditional mechanical filtration, motivating decision-makers to diagnose challenges and develop innovative strategies to mitigate the problem. More and more, in environments with high turnover of people (e.g., hospitals, hotels and shopping centers), fresh air ventilations are avoided and replaced by closed windows air purifier solutions to account for undesirable saturation of the atmosphere and the presence of pollutants such as PM10, PM2.5, PM1.0, nitrogen, and carbon oxides. The consensus is that polluting gases render the most efficient traditional filters ineffective. The ANSI/ASHRAE 62.1 and EN13779 standards reveal the absence of air treatment technologies that use the wet route in air conditioning systems. This work discusses the liquid air multi-venturi centrifugation technology of hydrodynamic precipitator purifiers in association with the synchronized and continuous monitoring of parameters (PM10, PM2.5, PM1.0, CO2) in the external urban environment and internal environments of a shopping center. It evaluates the performance of the wet route for the physical-chemical and biological treatment of air. Efficiency for retaining particulate matter in a single step without disposable filter reached levels above F9 (85-95% PM2.5), with a reduction of 82.4% for CO2. Wet route technology extends the air conditioner’s life, reducing external air flows and energy consumption by up to 13%, making IAQ a manageable and customizable variable. Among the conclusion of the investigation, the authors believe that the migration of industrial pollutant control technologies, such as liquid filtration promoted by gas scrubbers and hydrodynamic precipitators, should be considered as a first choice option due to the high efficiency achieved in the three types of pollutants to be controlled. That is micrometric particulate matter such as anthropogenic PM1.0 capable of reaching the lung alveoli, chemicals such as carbon dioxide and nitrogen, and biological assets such as viruses and bacteria that showed the vulnerability of HVAC-R systems during the COVID pandemic that rendered windowless corporate buildings unusable.
The Professor Merry Lecture: Endings and Beginnings
Authors: Merry Alan F.
Published: May 2024

Organ transplantation has become an established and worthwhile treatment for many otherwise intractable conditions in many countries around the world. For example, over 4000 patients have benefited from heart or lung transplants (or both) since the first heart transplant in Australia or New Zealand was carried out in 1984. However, there is thought to be a worldwide shortage of donors relative to the number of organs needed. Many people, notably many of those involved with situations in which organ donation might be possible, value the opportunity to contribute organs. This has led to interest in expanding the criteria for donation. Standard criteria donation (SCD) involves the formal diagnosis of brain death, and conservative criteria for donor eligibility. Extended criteria donation allows slightly more liberal eligibility criteria, thought acceptable in light of improved results in SCD. In donation after cardiac death (DCD), an alternative approach to increasing the pool of available donors, a formal diagnosis of brain death is not required. The formal diagnosis of brain death is very reliable, but prognosis in less definitive manifestations of severe brain damage is less so, as illustrated by numerous anecdotal reports. There is a tension between providing enough time between withdrawal of treatment and declaration of death for reasonable confidence to be maintained in the process of DCD and the desirability of keeping warm ischemic time to a minimum in the interest of organ survival. In Australia and New Zealand, DCD is undertaken only in the context of planned withdrawal of support in intensive care units (Maastricht category 3). There has been a considered and carefully implemented approach to DCD, and the educational initiatives associated with its introduction may have had incidental benefit to the SCD program as well. It is, nevertheless, important that all involved are cognizant of the practical and ethical issues at stake.
Human Error in Medicine: Change in Cardiac Operating Rooms through the FOCUS Initiative
Authors: Spiess Bruce D.
Published: May 2024

Human error in medicine is a significant cause of patient mortality. While there has been increased attention to safety in medicine since the Institute of Medicine publication To Err is Human, the profession at large has not progressed to the same degree as other highly complex industries such as aviation and nuclear power. The Flawless Operative Cardiovascular Unified Systems initiative (FOCUS) is a multi-year study/intervention to learn about and to improve human error in cardiac surgery. FOCUS has developed into an ongoing re-focusing through prospective interventional research schemes designed to effect positive change for improved patient care in cardiac surgery. The program was developed in conjunction with the Johns Hopkins University Quality and Safety Research Group using an approach termed Locating Errors through Network Surveillance (LENS). The LENS process was undertaken at Johns Hopkins University and another five centers where three major areas were examined observationally: interactions (communication) between operating room cardiac team members, clinical performance of known quality and safety dependent processes, and ergonomics/safety or human-machine interfaces. While collected data is currently being analyzed, preliminary results reveal over 800 human errors noted in the 40 cases observed. The errors observed are being categorized and taxonomy of errors is being created. Categories used in the FOCUS analysis include: teamwork and communication, compliance with existing protocols, knowledge or supervision, vigilance or situational awareness, equipment failure/design, poor operating room design/ergonomics, handoffs and transport problems, lack of professionalism, and ambiguity of responsibility. FOCUS is an initiative to change practice driven by science. Interventions based upon the observations already underway include efforts to decrease infection, adoption of the aviation concept of the “sterile cockpit”, briefing and debriefing, reduction of drug error, and peer-to-peer assessment. The first FOCUS data is sobering and shows tremendous possibility for improvement
Blood Management—Issues: The Panic of Coagulopathic Bleeding—Is There a Rational Approach?
Authors: Spiess Bruce D.
Published: May 2024

Blood management is an evolving field of reducing transfusions of allogeneic blood by maximizing multi-modality therapy to optimize red cell mass, reduce red cell loss, and harvest red cells that would have otherwise been discarded. These techniques are highly dependent upon teams working together. The programs are not just focused upon red cells but also on coagulation therapy. Coagulopathy is at times a difficult complex pathologic conundrum. In cardiac surgery the complexity is added to because of the inflammatory effects of anticoagulation, air/blood interfaces, and inflammation. Patients respond variably due to their own genetic and environmental factors. There can be a rational approach, thereby avoiding panic (a normal fear response) if the clinician utilizes not only the available laboratory technologies existing today but also follows published algorithms for treatment. These technologies with their coexisting algorithms have been widely shown to decrease blood usage, yet not to decrease bleeding. That finding suggests that therapy without such guidance wastes expensive pro-coagulant blood products and produces no advantage (a decrease in bleeding). When a therapy produces no advantage all that it leaves the patient with is the side effects or adverse outcomes. Adverse outcomes from coagulation products are real and sobering.
Prediction method for power fluctuations in cross regional consumption and transportation under the integration of new energy
Authors: Li Yajie , Wang Tao , Chen Shuting , Hu Xinmiao , Yin Rui , Yan Jun
Published: May 2024

Against the backdrop of the increasing development of the new energy industry, the volatility of new energy output poses significant challenges to regional power grid balance and energy absorption. Therefore, this article proposes a prediction method for cross regional transmission power fluctuations under new energy integration conditions. A comprehensive and representative sample dataset was constructed by comprehensively considering factors such as fluctuations in new energy output, capacity confidence, and peak shaving characteristic parameters, combined with numerical weather forecast data. Normalize the sample data to eliminate dimensional differences between parameters. The sparrow search algorithm is used to optimize the weights and thresholds of the double hidden layer BP neural network, effectively avoiding local optimization problems caused by over training. The experimental results show that this method has significant advantages in predicting power fluctuations in cross regional absorption and transportation of new energy, with a predicted power to power ratio of over 0.85.
Febrile Immunocompromised Renal Transplant Recipient with Allograft Dysfunction: Detection of an Undiagnosed Prostate Abscess by [18F]FDG-PET/CT along with Treatment Response Monitoring
Authors: Sonavane Sunita Nitin , Jamale Tukaram , Bose Sreyasi , Basu Sandip
Published: May 2024

The purpose of this report is to provide a comprehensive description of a post-transplant febrile patient's clinical course, complications, surgical procedure, and long-term management including evaluation by 18F-fluorodeoxyglucose [(18F)FDG] positron-emission tomography combined with computed tomography (PET/CT). A 35-year-old male, a postrenal transplant patient, developed chronic allograft dysfunction and presented with fever with chills, with suspicion of acute-on-chronic graft dysfunction, but no infective focus localization on chest X-ray, ultrasonography (USG) whole abdomen, or blood culture. Urine microscopy showed 8 to 10 pus cells/high-power field (hpf) and culture showed Klebsiella pneumoniae and Pseudomonas aeruginosa with low colony count. Culture-sensitive antibiotics were prescribed for 2 weeks, and after 3 weeks febrile episodes relapsed, symptoms progressed, and required emergency hospitalization due to acute painful urinary retention. Proteinuria and no growth were noted in urine analysis, serum creatinine was 5.36 mg/dL, and C-reactive protein was 15.7mg/dL, and remaining parameters were unremarkable. [18F]FDG-PET/CT was considered in order to resolve diagnosis, which revealed abnormal heterogeneous tracer uptake in the enlarged prostate with hypodense areas within, suggesting prostatitis with abscess formation and pyelonephritis in the upper pole of the transplant kidney. USG kidney urinary bladder (KUB) correlation confirmed prostatic abscess and transurethral drainage done, and pus culture revealed Burkholderia pseudomallei. Culture-sensitive intravenous meropenem treatment was given for 3 weeks. At 5 weeks, follow-up [18F]FDG-PET/CT showed low metabolic residual prostate uptake, suggesting a good response with residual infection. Thus, intravenous antibiotics was changed to oral antibiotics for another 6 weeks. His symptoms completely resolved at the end of treatment; however, his graft function worsened, with serum creatinine reaching 6 to 7 mg/dL, and eventually, after 8 months he became dialysis dependent.
Discrepancies in the newsworthiness of maritime security in Chinese and US media outlets: a corpus-based discursive news values analysis
Authors: Chen Cheng , Liu Renping
Published: May 2024

This article analyzes and compares the news values constructed in the English news reporting from Chinese and US mainstream media around events concerning maritime security, revealing how the related events have been packaged and sold differently in the two societies, uncovering the discrepancies in Chinese and US social visions on maritime security, and exploring the social attitudes underpinning the constant conflicts between the two countries in the marine sphere. Adopting corpus linguistic methods and the discursive news values analysis (DNVA) framework, this study examines news values through keywords, naming strategies, and images contained in Chinese and US mainstream English news outlets. The results show that Chinese media established the news values of Positivity and Proximity prominently through both textual and visual reporting, by emphasizing common international interests, advocating diplomatic joint cooperation and demonstrating optimistic attitudes towards the future of marine environment. By contrast, US media keenly construed Negativity and Eliteness, by highlighting the exclusive national interests/security of the US, dwelling on threats from other countries and distinctly demonstrating worries, fears, anger and violence. The differences in newsworthiness reflect that maritime security has been constructed in discrepant ways in Chinese and US society: as international joint security with optimistic perspective in China, and as exclusive national security with pessimistic perspective in US. This study has improved and supplemented the results of the previous China-US marine policy studies by the findings of the social emotions/cognition towards maritime policy revealed through newsworthiness analysis.
Molecular dynamics simulation study of nitrogen vacancy color centers prepared by carbon ion implantation into diamond
Authors: Zhao Wei , Xu Zongwei , Wang Pengfei , Chen Hanyi
Published: May 2024

Nitrogen vacancy (NV) color centers in diamond have useful applications in quantum sensing and fluorescent marking. They can be generated experimentally by ion implantation, femtosecond lasers, and chemical vapor deposition. However, there is a lack of studies of the yield of NV color centers at the atomic scale. In the molecular dynamics simulations described in this paper, NV color centers are prepared by ion implantation in diamond with pre-doped nitrogen and subsequent annealing. The differences between the yields of NV color centers produced by implantation of carbon (C) and nitrogen (N) ions, respectively, are investigated. It is found that C-ion implantation gives a greater yield of NV color centers and superior location accuracy. The effects of different pre-doping concentrations (400–1500 ppm) and implantation energies (1.0–3.0 keV) on the NV color center yield are analyzed, and it is shown that a pre-doping concentration of 1000 ppm with 2 keV C-ion implantation can produce a 13% yield of NV color centers after 1600 K annealing for 7.4 ns. Finally, a brief comparison of the NV color center identification methods is presented, and it is found that the error rate of an analysis utilizing the identify diamond structure + coordination analysis method is reduced by about 7% compared with conventional identification methods.
Gassing up potential for silicon microring resonators
Authors: Ikenson Ben
Published: May 2024

Novel design opens possibilities for nanophotonic integrated circuits, on-chip sensitive gas sensing, and more.
GelMA micropattern enhances cardiomyocyte organization, maturation, and contraction via contact guidance
Authors: Zhang Bin , Luo Yichen , Zhou Xue , Gao Lei , Yin Xiaohong , Yang Huayong
Published: May 2024

Cardiac tissue engineering has emerged as a promising approach for restoring the functionality of damaged cardiac tissues following myocardial infarction. To effectively replicate the native anisotropic structure of cardiac tissues in vitro, this study focused on the fabrication of micropatterned gelatin methacryloyl hydrogels with varying geometric parameters. These substrates were evaluated for their ability to guide induced pluripotent stem cell-derived cardiomyocytes (CMs). The findings demonstrate that the mechanical properties of this hydrogel closely resemble those of native cardiac tissues, and it exhibits high fidelity in micropattern fabrication. Micropatterned hydrogel substrates lead to enhanced organization, maturation, and contraction of CMs. A microgroove with 20-μm-width and 20-μm-spacing was identified as the optimal configuration for maximizing the contact guidance effect, supported by analyses of nuclear orientation and F-actin organization. Furthermore, this specific micropattern design was found to promote CMs' maturation, as evidenced by increased expression of connexin 43 and vinculin, along with extended sarcomere length. It also enhanced CMs' contraction, resulting in larger contractile amplitudes and greater contractile motion anisotropy. In conclusion, these results underscore the significant benefits of optimizing micropatterned gelatin methacryloyl for improving CMs' organization, maturation, and contraction. This valuable insight paves the way for the development of highly organized and functionally mature cardiac tissues in vitro.
Air–liquid intestinal cell culture allows in situ rheological characterization of intestinal mucus
Authors: Cai Pamela C. , Braunreuther Margaret , Shih Audrey , Spakowitz Andrew J. , Fuller Gerald G. , Heilshorn Sarah C.
Published: May 2024

Intestinal health heavily depends on establishing a mucus layer within the gut with physical properties that strike a balance between being sufficiently elastic to keep out harmful pathogens yet viscous enough to flow and turnover the contents being digested. Studies investigating dysfunction of the mucus layer in the intestines are largely confined to animal models, which require invasive procedures to collect the mucus fluid. In this work, we develop a nondestructive method to study intestinal mucus. We use an air–liquid interface culture of primary human intestinal epithelial cells that exposes their apical surface to allow in situ analysis of the mucus layer. Mucus collection is not only invasive but also disrupts the mucus microstructure, which plays a crucial role in the interaction between mucus and the gut microbiome. Therefore, we leverage a noninvasive rheology technique that probes the mechanical properties of the mucus without removal from the culture. Finally, to demonstrate biomedical uses for this cell culture system, we characterize the biochemical and biophysical properties of intestinal mucus due to addition of the cytokine IL-13 to recapitulate the gut environment of Nippostrongylus brasiliensis infection.
Generating quantum correlated photon pairs in a hybrid silicon–BTO platform
Authors: Marchant D. , Faruque I. , Barreto J.
Published: May 2024

Here, we show photon pair generation from ring resonator and waveguide structures in a hybrid silicon–BTO on an insulator platform with a pulsed pump. Our analysis of single photon and coincidence generation rates show that spontaneous four-wave mixing is comparable to that expected from SOI devices with similar characteristics and find γeff of (14.7 ± 1.3) and (2.0 ± 0.3) MHz/mW2 for ring resonator and waveguide structures, respectively.
Efficient guiding and focusing of intense laser pulse using periodic thin slits
Authors: Xu L. , Huang T. W. , Jiang K. , Wu C. N. , Peng H. , Chen P. , Li R. , Zhuo H. B. , Zhou C. T.
Published: May 2024

Slits have been widely used in laser–plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle beams. Here, we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser pulse. The fundamental physics of intense laser interaction with thin slits is studied, and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing regime. In addition, the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional waveguides. These results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.
Optimized deep learning regression assisted wear rate analysis of Cu–AlCoCrCuFe HEA composite
Authors: S. Seenivasan , P. Satishkumar , Prakash K. Soorya , Giri Jayant , Al-Lohedan Hamad A. , Sathish T.
Published: May 2024

At present, composites have brought materials to a new era with superior characteristics. The proper selection of materials with optimal processing conditions is one of the prime factors in determining the efficiency of composites. This article introduces a new composite by fabricating a copper matrix with reinforced AlCoCrCuFe High Entropy Alloy (HEA). The ultimate theme of this research is to forecast the wear rate of the Cu–AlCoCrCuFe HEA composite. Using the pin on the disk, the wear test is carried out on varying combinations of parameters. Then Taguchi analysis is carried out to get the precise fit parameters. The wear rate mainly depends on the percentage of HEA, sliding distance, sliding velocity, and the load applied. Correlation analysis is performed to determine the exact parameter determining the optimal wear rate and the coefficient of friction. After feature extraction, the parameters are optimized, and the neural network regression is given the optimized parameters. The network has been trained, and predictions are made using it. The model successfully predicts the wear rate, as evidenced by the declining RMSE of 0.28 and rising R2 values up to 92%. The analysis shows a significant decline in the wear rate with HEA additions. In addition, the wear rate increases with a rise in load, sliding velocity, and sliding distance.
Kriging surrogate model for optimizing outlet temperature distribution in low-emission combustors without dilution holes
Authors: Wang Kefu , Li Feng , Zhou Tao , Wang Dichang
Published: May 2024

Designing advanced combustors that operate at high temperatures and produce little pollution, especially in the absence of primary and dilution holes, is a difficult task that may bring significant challenges. In this regard, this paper introduces a Kriging surrogate model approach to optimize the outlet temperature distribution of the combustor to achieve such advanced low-pollution combustors. Building upon previous research, this study explores the effects of the swirler blade installation angle on the outlet temperature distribution of the combustor without primary or dilution holes. Traditional methods, such as the control variable method using computational fluid dynamics (CFD) for numerical simulation, are limited in application due to the complex coupling of flow, heat transfer, mass transfer, and combustion processes. In contrast, surrogate models, especially the Kriging model, offer a rapid and efficient alternative to extensive CFD simulations that provide accurate predictions and error estimates for the solution of the problem. In summary, this paper details the process of generating sample points through three-dimensional numerical simulations, develops a Kriging surrogate model through Latin hypercube sampling, and optimizes the model to identify the most uniform outlet temperature distribution achievable by adjusting the installation angle of the swirl blade. The optimal design parameters, which are quickly obtained through the Kriging model, showed a significant reduction in the overall temperature distribution function and the radial temperature distribution function by 21% and 27.14%, respectively.
Capacity optimization of independent hybrid renewable energy system under different operational strategies based on improved gray wolf algorithm
Authors: Lu J. , Siaw F. L. , Thio T. H. G. , Wang J. J.
Published: May 2024

Renewable energy sources such as wind and solar power exhibit strong stochasticity and volatility, resulting in decreased power supply security and sustainability. A strategically optimized hybrid renewable energy system (HRES) is crucial for maintaining stable load operations and achieving sustainable energy development. This paper introduces an energy optimization management model for an independent HRES consisting of wind turbines, photovoltaic systems, diesel generators, and energy storage units. Operational strategies focus on energy storage-led loads following diesel generator-led load prioritizations. The model aims to optimize objectives to include economic, environmental, and power supply reliability indices. A dynamic adaptive parameter approach balances the parameters of the objective function at various instances. The optimal capacity allocation of the model is solved using the improved gray wolf optimization (IGWO) algorithm. This approach incorporates the golden sine strategy, the levy flight strategy, and the dynamic inverse learning strategy into the traditional GWO algorithm. Analyzing different test functions, evaluation metrics, and actual load data indicates that the proposed algorithm excels in global optimization capabilities and search speeds. The model significantly reduces the economic and environmental costs of the HRES microgrids and improves the sustainable development of renewable energy in various scenarios.
Current dependence of output voltage and discharge capacity of a tertiary battery
Authors: Ozaki Eishi , Shibata Takayuki , Nagai Ichiro , Ohnuki Hitoshi , Moritomo Yutaka
Published: May 2024

Tertiary batteries (TBs), which can be charged by a temperature change (ΔT), are prospective energy-harvesting devices. In this work, we investigated the variations in the output voltage (VTB) and discharge capacity (QTB) with current (I) of NaxCo[Fe(CN)6]0.87/NaxNi[Fe(CN)6]0.94 TBs (ΔT of 30 K) per unit weight of total active materials at 45 °C. Reflecting the battery resistance R, VTB(I) decreases with increasing I as VTBIRI=VTB0−MRI, where M is the total weight of the active material. We found that QTB(I) had values that were slightly smaller than those obtained by incorporating only the voltage-drop effect, QTBIRI=QTB(0)×VTBIR(I)VTB(0). The deviation between the observed QTB(I) and QTBIR(I) can be accurately explained in terms of the I-induced deformation of the discharge curve.
Modeling and analysis of magnetic resonance wireless transmission coil
Authors: He Liping , Lu Pengfei , Liu Hongshun
Published: May 2024

Wireless transmission technology is a new type of power transmission technology with electric and magnetic fields as the medium. It has more advantages in transmission direction, transmission characteristics, security, and penetration. The model of a magnetically coupled resonant radio energy transmission system is designed. The main parameters such as resonance frequency and mutual inductance are considered comprehensively. The model is designed using the equivalent topological circuit structure of mutual inductance coupling. The equivalent parameters in the circuit topology can be affected by setting the size of the coil, the distance between the coils, the excitation size, and the high frequency. The structure parameters of the whole system are modeled and calculated by the Ansoft Maxwell software. At the same time, the influence on the power and efficiency of wireless power transmission is explored by several factors such as the coil diameter, the distance between the transmitting end and the receiving end, and the resonance frequency of the system, so as to achieve the purpose of verifying the technical characteristics of wireless power transmission. The key factors that may affect the transmission efficiency and power of the system are analyzed in detail by deriving the calculation model of transmission efficiency and power.
In-plane gate induced transition asymmetry of spin-resolved Landau levels in InAs-based quantum wells
Authors: Chiatti Olivio , Boy Johannes , Heyn Christian , Hansen Wolfgang , Fischer Saskia F.
Published: May 2024

The crossover from quasi-two- to quasi-one-dimensional electron transport subject to transverse electric fields and perpendicular magnetic fields is studied in the diffusive to quasi-ballistic and zero-field to quantum Hall regime. In-plane gates and Hall-bars have been fabricated from an InGaAs/InAlAs/InAs quantum well hosting a 2DEG with a carrier density of about 6.8 × 1011 cm−2, a mobility of 1.8 × 105 cm2/Vs, and an effective mass of 0.042me after illumination. Magnetotransport measurements at temperatures down to 50 mK and fields up to 12 T yield a high effective Landé factor of g*=16, enabling the resolution of spin-split subbands at magnetic fields of 2.5 T. In the quantum Hall regime, electrostatic control of an effective constriction width enables steering of the reflection and transmission of edge channels, allowing a separation of fully spin-polarized edge channels at filling factors ν = 1 und ν = 2. A change in the orientation of a transverse in-plane electric field in the constriction shifts the transition between Zeeman-split quantum Hall plateaus by ΔB ≈ 0.1 T and is consistent with an effective magnetic field of Beff ≈ 0.13 T by spin-dependent backscattering, indicating a change in the spin-split density of states.
k-space holographic multiplexing for synthetic aperture diffraction tomography
Authors: Huang Zhengzhong , Cao Liangcai
Published: May 2024

Optical diffraction tomography can be performed with low phototoxicity and photobleaching to analyze 3D cells and tissues. It is desired to develop high throughput and powerful data processing capabilities. We propose high bandwidth holographic microscopy (HBHM). Based on the analyticity of complex amplitudes, the unified holographic multiplexing transfer function is established. A high bandwidth scattering field is achieved via the k-space optical origami of two 2D wavefronts from one interferogram. Scanning illumination modulates the high-horizontal and axial k-space to endow synthetic-aperture from 2D high space-bandwidth product (SBP) scattering fields. The bright-field counterpart SBP of a single scattering field from HBHM is 14.6 megapixels, while the number of pixels is only 13.7 megapixels. It achieves an eight-fold SBP enhancement under the same number of pixels and diffraction limit. The HBHM paves the way toward the performance of high throughput, large-scale, and non-invasive histopathology, cell biology, and industrial inspection.
Tunable ultra-broadband terahertz metamaterial absorbers based on complementary split ring-shaped graphene
Authors: Ri Kwang-Jin , Kang Ryong-Ju , Ri Chung-Ho
Published: May 2024

In the design of graphene-based tunable broadband terahertz (THz) metamaterial absorbers (MAs), simplifying the gating structure to control the Fermi energy of graphene is a critical requirement for practical applications. To solve this problem, we numerically demonstrate two kinds of tunable ultra-broadband THz MAs based on complementary split ring-shaped graphene. The first absorber exhibits an ultra-broadband absorption performance with an absorptance of above 90% in the frequency range of 2.06–4.24 THz, with a relative absorption bandwidth of 69.2%. By changing the Fermi energy of graphene from 0 to 0.8 eV through bias voltage, the absorptance can be tuned from 32.8% to 99.9%. The ultra-broadband absorption mechanism is based on the surface plasmon polariton resonances caused by the surface charges of complementary split ring-shaped graphene. In addition, to further expand the absorption bandwidth, we cover another dielectric layer on the first absorber to make the second absorber have an increased relative absorption bandwidth of 108.27%.
Study on hydrogen desorption of ZrCoH3 promoted by doping Hf and Ti with DFT
Authors: Yang Youshan
Published: May 2024

This work aims to provide new insights into the hydrogen evolution of ZrCoH3. The transition metal elements Hf and Ti are designed to be added to ZrCoH3 by occupying Co atoms, Zr atoms, and interstitial sites. The effects of Hf and Ti atoms on the hydrogen evolution of ZrCoH3 are investigated through a first-principles study. The results show that the doping of Hf and Ti atoms can effectively improve the hydrogen desorption ability of ZrCoH3, which is related to the weak Co–H covalent interaction in the doping system, metallic properties, and the formation of Hf/Ti–H bonds. Hf atom doping has the best catalytic effect on the dehydrogenation of ZrCoH3, and the Hf atom can easily enter the ZrCoH3 body to form the Zr16Co16HfH48 compound. Although the Zr15Co16HfH48 compound has a low hydrogen dissociation energy and exhibits good hydrogen desorption performance, it requires a high energy cost when Hf occupies the Zr site in practical applications. When doped with the same element, the occupancy energy and hydrogen dissociation energy are inversely related. The hydrogen dissociation energy of ZrCoH3 is negatively correlated with the electronegativity of the dopant atom, namely, the lower the electronegativity of the dopant atom, the smaller the hydrogen dissociation energy of the system. This study confirms by simulation calculations that the use of low electronegativity metals to recombine with ZrCoH3 is an effective way to achieve ZrCoH3 destabilization.
First-principles calculation of P-type Mg3Sb2 thermoelectric performance modification by Ge and Si doping
Authors: Wang Chengjiang , Wang Zhenghao , Yang Yifu , Zhang Ke , Wang Feifan
Published: May 2024

Mg3Sb2 has been considered a highly promising thermoelectric material for mid-temperature applications. Optimizing the properties of the material is crucial for accelerating its commercial use. In this work, first-principles molecular simulations of P-type Mg3Sb2 doped with the carbon group elements Ge and Si have been carried out. Results indicate that doping with Ge and Si enhances the thermodynamic stability and electrical conductivity of the material. This improvement is achieved by decreasing the bandgap, increasing the local and peak density of states, flattening the band structure, and elevating the relative mass of carriers. Additionally, doping with Ge and Si decreases the phonon velocity and Debye temperature, which weakens the thermal transport properties of the material. These findings suggest that Ge and Si doping is an effective method for improving the thermoelectric properties of the material. At the same doping concentration, the Si single-doped system possesses the smallest bandgap value with the highest peak density of states and forms an indirect bandgap, leading to the best electrical transport properties; the Ge single-doped system has the lowest phonon velocity and Debye temperature, which has the most significant effect in attenuating the thermal transport properties of the material; and the Ge–Si co-doped system has the highest relative mass of carriers, which is conducive to the enhancement of Seebeck coefficient. The results offer theoretical guidance for experimentally analyzing the effects of Ge and Si doping on the thermoelectric properties of Mg3Sb2.
The influence of point defects on the electronic structures and optical properties of 3C-SiC
Authors: Zhang Ye , Jiang Shangting , Li Ye , Chen Changchang , Chen Zhiyong , Wang Xinlin
Published: May 2024

Using first-principles calculations, we studied the formation energy of point defects in cubic silicon carbide (3C-SiC) and the influences of defects on its electronic band structure, density of states, and optical properties. We found that the formation energy of the interstitial defect is greater than that of the vacancy and antisite defect, with the Si interstitial defect having the highest formation energy. The electronic band structure and density of states have no bandgap due to the vacancy defect, interstitial defect, and Si antisite defect (Si atom occupies the position of C atom), while the changes due to the C antisite defect (C atom occupies the position of Si atom) are not significant. Depending on the type of defect, the optical properties change differently, with the vacancy defect having the most significant impact on the optical properties. The vacancy defect notably increases the optical conductivity, dielectric function, reflectivity, extinction coefficient, and refractive index in the low-energy region, indicating the potential application of 3C-SiC in the field of optoelectronic devices.