bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Method to Describe the Alignment Between Renewable Power Supply and Demand in Order to Derive Storage Needs
Authors: Reichert Arnd 
Published: October 2022

Abstract
In times, when power generation exceeds demand or prices are low, excess energy can be stored for later use. The stored energy is used in the opposite case when power consumption exceeds generation.
For an energy system where, renewable energy is targeted to be the main source of power generation on our way to carbon neutrality, it is important to understand how much energy needs to be stored to maximize the direct and domestic utilization of the generated energy and thus, to minimize the amount of imported and exported energy. The needed capacity of an energy storage device depends on how well the renewable power generation and consumption are aligned over time. Hence, a description of the alignment between the power generation of renewable energy sources and the power consumption is key to understand energy storage capacity needs.
In this paper a simple method to describe power consumption / consumption alignment and how to derive storage capacity needs from this description is presented. The method can be applied to existing supply / demand data or to simulation results to reduce the simulation effort. The effects of capacity modifications to a power generation and storage system can be easily analyzed. The method can be widely applied to a single project or to an entire nation-wide energy-system, to analyze time periods from a day to a month or a year.
The application of the method is shown by three examples: The first one is a photovoltaic system with a battery storage of different sizes and over different time periods. The second and third example is the renewable energy system of a whole country. The results of the method and the limits of the application of the method are discussed.
Impact of Inlet Conditions on Performance of a Supercritical CO2 Centrifugal Compressor
Authors: Jiang Xudong , Wang Zhiheng , Xi Guang 
Published: October 2022

Abstract
The centrifugal compressor is one of the core components in a supercritical carbon dioxide (SCO2) Brayton cycle, in which the inlet state is near the critical point of CO2 to reduce the compression work. However, the thermodynamic properties of CO2 change dramatically near the critical point. Therefore, the performance and flow in a SCO2 compressor will be sensitive to the variation of inlet conditions. In this paper, a centrifugal compressor stage designed by the in-house code for a 20MW supercritical CO2 Brayton cycle is numerically investigated with the variation of considered inlet state point. Firstly, to take account of the nonlinear variation of the properties near the critical point, the accuracy of look-up table of CO2 properties is evaluated and implemented into the commercial CFD software. Then, the effect of small change in inlet temperature or pressure near the critical point on the compression process and performance is investigated, and the flow fields in compressor with different inlet states are compared. It is shown that the CFD-predicted compressor performance is highly sensitive to the resolution of look-up table as well as the inlet conditions. Slight increase in inlet temperature or inlet pressure will cause a significant decrease in pressure ratio. The impact of small change of inlet state on the flow structures are mainly concentrated on the first half of impeller blade passage.
From Pressure Time Series Data to Flame Transfer Functions: A Framework for Perfectly-Premixed Swirling Flames
Authors: Ghani Abdulla , Albayrak Alp 
Published: October 2022

Abstract
We present a two-step optimization (TSO) framework, which uses the pressure data of an unstable combustion process to estimate the complex-valued Flame Transfer Function (FTF). From the pressure time series, we obtain the instability frequency and the amplitudes of the pressure fluctuations. The first optimization step is based on an acoustic network model of the combustor: the TSO approach makes use of the pressure data to find a simplified n-τ model, which reproduces the unstable combustion process. This step has already been validated for the Rijke tube, a laminar and a turbulent flame in Ghani et al. J. Eng. Gas Turb. and Power 142 (12) 2020. The major contribution of this work adds a second optimization loop to extend the n-τ model to the complex-valued FTF: the gain and phase obtained by the n-τ model are used to fit a distributed time delay model based on the work of Komarek & Polifke, J. Eng. Gas Turb. and Power 132 (6) 2010. Our proposed method is applied to a turbulent, premixed, swirl-stabilized flame operated at two power ratings (SI30kW and 70kW) and two swirler positions. The model results for the FTFs are compared against experimentally measured FTFs for these four configurations and all agree well. To the best of our knowledge, this is the first attempt to estimate the complex-valued FTF solely based on pressure measurements. Compared to classical methods for FTF determination such as experimental tests or numerical simulations, our TSO approach is fast and accurate. The proposed framework is suitable for perfectly-premixed flames stabilized by a swirling flow field, requires two pressure sensors placed at distinct axial locations and is easy to implement.
Ammonia as an Aircraft Fuel: Thermal Assessment From Airport to Wake
Authors: Otto Marcel , Vesely Ladislav , Kapat Jayanta , Stoia Michael , Applegate Nicholas D. , Natsui Greg 
Published: October 2022

Abstract
Over the past two decades, zero-emission aviation initiatives have focused on using drop-in biofuels and sustainable aviation fuels (SAF) to replace fossil-based jet fuels to achieve near-term reductions in carbon emissions with minimal impacts on the global aircraft fleet and supporting infrastructure. While significant advances have been made in the production of such fuels, scaling up manufacturing capability to provide cost-competitive drop-in fuels has been a challenge.
This paper discusses ammonia as a carrier of electricity-derived, green hydrogen for aviation, with near-zero emission. Ammonia is proposed as both a carrier of hydrogen as fuel and to provide cooling for compressor intercooling and cooled cooling air for NOx elimination and condensation of water vapor in the exhaust to reduce contrail formation. The performance of ammonia with regard to all of these objectives will be evaluated. A detailed analysis of the energetics concerning the flow of ammonia from leaving the airport storage, to the fuel tanks of the aircraft to the wake of the engine will be performed. Conclusions will be drawn on how ammonia compares to Jet A, SAF, and hydrogen in overall performance as aviation fuel.
Investigation of Unsteady Rotor-Stator Interaction and Deterministic Correlation Analysis in a Transonic Compressor Stage
Authors: Liu Yangwei , Wei Xindi , Tang Yumeng 
Published: October 2022

Abstract
Unsteady blade row interaction (UBRI) has a large impact on performance in high speed axial compressors, thus, the influence of UBRI should be accurately predicted in compressor routine design. In this study, the unsteady rotor-stator interaction in a transonic single stage compressor, NASA Stage 35, is studied by steady and unsteady Reynolds-Averaged Navier-Stokes (RANS) methods. Firstly, the UBRI is analyzed. Periodic separation bubbles on stator suction surface induced by the rotor wake are observed. Comparisons between steady and unsteady results show that the radial distribution of flow angle near the hub and tip region of the stator is strongly influenced by UBRI. Secondly, deterministic correlations are analyzed based on the average-passage equation system (APES). The distribution of deterministic stress, the relationship between harmonics and decay rate of deterministic correlations, and the relationship between spatial correlations and deterministic correlations are analyzed. Results show that a strong non-linear interaction caused by the rotor wake and the stator potential field is found in the rotor-stator gap, and it is responsible for the generation of spatial-time correlation. It is found that the decay rate of deterministic correlation is highly related to the corresponding harmonics. The higher order harmonic owns higher decay rate. Then a modified exponential decay model for deterministic correlation based on harmonics is proposed, and shows a better performance. At last, the anisotropy of deterministic correlations is analyzed using Lumley triangle. Results show that the deterministic stress is highly anisotropic in the stator passage, which could be considered in the modeling if using similar strategy of turbulence modeling.
The Ordovician South Mayo Trough, a basin that recorded the passage of a triple junction along the Laurentian margin
Authors: Ryan* Paul D. , Dewey John F. 
Published: October 2022

ABSTRACT
Tectonic models for arc-continent collision can be overly complex where, for example, diachronous sedimentation and deformation along a single plate boundary are attributed to separate tectonic events. Furthermore, continuous sedimentation in a single basin recording a diachronous collision along a plate margin makes it difficult to use classical unconformable relationships to date an orogenic phase. In this chapter, we describe the Ordovician South Mayo Trough of western Ireland, a remarkable example of such a basin. It originated in the late Cambrian–Early Ordovician as a Laurentia-facing oceanic forearc basin to the Lough Nafooey arc. This arc was split by a spreading ridge to form a trench-trench-ridge triple junction at the trench. The basin remained below sea level during Grampian/Taconic arc-continent collision and, following subduction flip, received sediment from an active continental margin. Sedimentation ended during Late Ordovician Mayoian “Andean”-style shortening, broadly coeval with a marked fall in global sea level. These major tectonic events are traced through the nature of the detritus and volcanism in this basin, which is preserved in a mega-syncline. The Grampian orogen is not recorded as a regional unconformity, but as a sudden influx of juvenile metamorphic detritus in a conformable sequence.
Access to HIV healthcare services by farm workers in sub-Saharan Africa (SSA): a systematic review protocol
Authors: Mlangeni Nosimilo , Adetokunboh Olatunji , Lembani Martina , Malotle Molebogeng , Nyasulu Peter 
Published: October 2022

IntroductionSub-Saharan Africa (SSA) region harbours the highest burden of HIV infections in the world. Agricultural work has been reported as one of the occupations with a high prevalence of HIV. Farm workers generally have poor access to health services, which prevents them from receiving proper HIV prevention and care. Furthermore, poor policies and policy implementation, and lack of workplace programmes increases farm workers’ vulnerability to HIV infection. Thus, the aim of this study is to conduct a systematic review to assess HIV prevention and treatment services and national policies governing access to healthcare services by farm workers in SSA.Methods and analysisOur systematic review will include studies published from January 1990 to December 2021 within SSA countries. We will use a sensitive search strategy for electronic bibliographic databases and grey literature sources. Databases will include PubMed, CINAHL, Cochrane library, African Index Medicus and Scopus. The main outcomes to be reported will be HIV policy for farmworkers, availability of HIV prevention service(s), availability of treatment and support to farmworkers who are living with HIV, presence of referral structures for farmworkers through the health system and follow-up services for farmworkers who are on antiretroviral therapy. We will synthesise the main characteristics of included studies and use summary measures to describe study characteristics. In a situation where data are not sufficiently homogeneous to perform a quantitative synthesis, we will conduct a narrative synthesis. We will explore themes and relationships between included studies for qualitative data.Ethics and disseminationThe study will use publicly available data and ethics exemption has been obtained from Human Research Ethics Committees, Faculty of Medicine & Health Sciences, Stellenbosch University. The results of this study will be disseminated through peer-reviewed journals, conference presentations and seminars.PROSPERO registration numberCRD42021277528.
Stroke prevention of thoracoscopic left atrial appendage clipping in patients with non-valvular atrial fibrillation at high risk of stroke and bleeding: study protocol for a non-randomised controlled clinical trial
Authors: Ye Cong , Han Xuesong , Chen Yiming , Liu Fei , Ma Hao , Yang Yu , Liu Yang , Hu Qingfeng , Yao Qing , Xie Wenting , Xu Dong 
Published: October 2022

IntroductionNon-valvular atrial fibrillation (NVAF) is a high-risk factor for ischaemic stroke. The 2016 European Society of Cardiology Atrial Fibrillation Management guidelines recommend oral anticoagulants (OACs) to prevent stroke in men with CHA2DS2-VASc scores ≥2 and women ≥3. However, in patients with a high risk of stroke and a high risk of bleeding (HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly (> 65 years), Drugs/alcohol concomitantly) score≥3), OAC had a higher risk of bleeding. Left atrial appendage closure (LAAC) is non-inferior to OAC as a means of preventing stroke in several studies. As a minimally invasive intervention to prevent stroke, transthoracic LAAC (TS-LAAC) has a high successful closure rate, but there is a lack of literature reports directly comparing it with OAC. Our research compares TS-LAAC with novel oral anticoagulants (NOACs) and provides an appropriate programme for stroke prevention in a specific population.Methods and analysisThis is a non-randomised controlled trial study protocol, and we will conduct this study from April 2022 to April 2025. The study included 186 patients with confirmed NVAF, 93 of whom completed thoracoscopic LAAC, and the control group treated with NOACs. The primary outcome was the incidence of stroke and systemic embolism, as well as the composite endpoint events (stroke, systemic embolism, myocardial infarction, bleeding, cardiovascular death, etc). Secondary outcomes were ischaemic stroke, haemorrhagic stroke, any bleeding events, death from cardiovascular causes, death from all causes, residual root rate in the surgery group, device-related thrombosis in the surgery group, changes in blood pressure, cardiac chamber size changes, etc. Each subject completed at least 1 year of follow-up.Ethics and disseminationThe study has been approved by the Medical Ethics Committee of Beijing Tiantan Hospital, Capital Medical University, China (approval number: KY2022-013-02). The results from this study will be disseminated through manuscript publications and national/international conferences.Trial registration numberChiCTR2200058109.
Cohort profile: a prospective Australian cohort study of women’s reproductive characteristics and risk of chronic disease from menarche to premenopause (M-PreM)
Authors: Chan Hsiu-Wen , Dharmage Shyamali , Dobson Annette , Chung Hsin-Fang , Loxton Deborah , Doust Jenny , Montgomery Grant , Stamatakis Emmanuel , Huxley Rachel R , Hamer Mark , Abbott Jason , Yeap Bu Beng , Visser Jenny A , McIntyre Harold , Mielke Gregore Iven , Mishra Gita D 
Published: October 2022

PurposePrevious studies have identified associations between individual reproductive factors and chronic disease risk among postmenopausal women. However, few have investigated the association of different markers of reproductive function, their interactions and risk factors of chronic disease among women approaching menopause. The Menarche-to-PreMenopause (M-PreM) Study aims to examine the relationship between reproductive factors across the reproductive lifespan and risk indicators for chronic disease among women in their early-to-mid-40s. The purpose of this cohort profile paper is to describe the rationale, study design and participant characteristics of the M-PreM Study.ParticipantsWomen born in 1973–1978 who participated in the Australian Longitudinal Study on Women’s Health (ALSWH) were invited to undertake a clinical or self-administered assessment. A total of 1278 women were recruited from June 2019 to June 2021.Findings to dateThe study measures included functional, cognitive and cardiometabolic tests, anthropometry, spirometry, respiratory health questionnaires, physical activity, sleep patterns, sex hormones, and cardiovascular and metabolic markers; whereas blood and saliva samples were used for the analysis of genetic variants of genes associated with reproductive characteristics and chronic disease. The mean age of the clinic and self-assessed participants was 44.6 and 45.3 years, respectively. The menopausal status of participants was similar between the two arms of the study: 38%–41% premenopausal, 20% perimenopausal, and 36% took oral contraception or hormone replacement therapy. Approximately 80% of women had at least one child and participants reported experiencing pregnancy complications: preterm birth (8%–13% of pregnancies), gestational diabetes (10%) and gestational hypertension (10%–15%).Future plansThe biomedical data collected in the M-PreM Study will be linked to existing ALSWH survey data on sociodemographic factors, health behaviour, reproductive function, and early life factors collected over the past 20 years and health administrative data. The association between reproductive factors and risk indicators of chronic disease will be analysed.
Spin-1/2 “bosons” with mass dimension 3/2 and fermions with mass dimension 1 cannot represent physical particle states
Authors: Aguirre A. R. , Chaichian M. M. , e Silva B. A. Couto , Sánchez-Vega B. L. 
Published: October 2022

AbstractWe delve into the first principles of quantum field theory to prove that the so-called spin-1/2 “bosons” and the fermions with mass dimension 1, including ELKO, cannot represent physical particle states with spin 1/2. Specifically, we first demonstrate that both aforementioned fields are not invariant under rotational symmetry, which implies that the particles created for these fields are not eigenstates of the spin operator in the $$(\frac{1}{2},0)\oplus (0,\frac{1}{2})$$

(

1
2

,
0
)

⊕

(
0
,

1
2

)

representation of the Lorentz group, nor is it possible to construct a Hamiltonian density scalar under the rotational group from them. Furthermore, following Weinberg’s approach to local causal fields, we prove that regardless of any discrete symmetry or adjoint structure, the relativistic fields in the $$(\frac{1}{2}, 0) \oplus (0,\frac{1}{2})$$

(

1
2

,
0
)

⊕

(
0
,

1
2

)

representation satisfy the Fermi-Dirac statistics in complete agreement with the well-established spin-statistics theorem and experimental results.
Molecular Scale Simulations of Coating Palmitic Acid Molecules on Aluminum Surface
Authors: Liu Yi , Sun Ruochen , Liu Pingan , Xu Jiangtao 
Published: October 2022

In this research, molecular dynamic (MD) simulations computation is applied to generally study the coating behavior of palmitic acid molecules and aluminum (Al) nanoparticle (ANP) surface through single and multi-molecule models. Changes and comparisons of adsorption distance, energy, effectiveness and stability are generally discussed in this study. Those obtained results indicate that the adsorption configuration of palmitic acid and Al has shown the adsorption polarity clearly. For carboxyl terminal of palmitic acid and Al surface, when their critical adsorption angle is around 60∘, its distance is within 9 Å. Besides, the decisive atomic group of palmitic acid molecule is carboxyl, whose oxygen atom with double bond can adsorb the Al atom stably. This adsorption effect and formation is close to the covalent bond. During the adsorption process, van der Waals force acts on the long-distance attraction, and the Coulomb force acts more critically as the short-range adsorption force. Finally, the gas coating has proper advantages over the liquid coating, as the erosion of Al surface is much lower when it is surrounded by gas-phased palmitic acid.
Arctic bivalve dead-shell assemblages as high temporal- and spatial- resolution archives of ecological regime change in response to climate change
Authors: Meadows Caitlin A. , Grebmeier Jacqueline M. , Kidwell Susan M. 
Published: October 2022

Abstract
A 15-year time-series of data on benthic community response to rapid climate change at a biomass ‘hotspot’ in the northern Bering Sea, Alaska, provides an exceptional opportunity to evaluate naturally occurring molluscan dead-shell assemblages as ecological archives. We find that, at five middle-shelf stations censused annually from 2000 to 2014, dead-shell assemblages collected in 2014 are dominated by obligate deposit-feeding Nuculanidae bivalves as opposed to the other families in that guild or the facultative deposit-feeding Tellinidae that dominate the most recent living bivalve assemblages, thus correctly detecting the location and direction of known ecological changes. However, live–dead contrast is significant where the bivalve biomass and abundance has declined over time, and muted where bivalve abundances, and therefore shell input, increased, underscoring the general danger of assuming constant shell input. We also find that proportional abundance-based measures are best suited for detecting benthic response to climate change. Combined with preliminary results from shell age-dating, these results indicate that dead-shell assemblages provide a short-lived but compositionally faithful ecological memory well-suited for detecting recent site- and habitat-level ecological change under cold-water conditions. With marine regime change suspected to now be underway throughout the Arctic, molluscan dead-shell assemblages should become an integral part of efforts to detect transitioning regions.