Partial Configuration Research Articles

Analysis of ludo-shaped configuration of PV arrays under different partial shaded configuration

Analysis of ludo-shaped configuration of PV arrays under different partial shaded configuration

Seismic performance on PSPC beam - concrete encased CFST column frame with a built-in reduced beam section

The concrete-filled steel tubular (CFST) column is widely used to connect with a steel beam owing to the quick dry connection and acceptable seismic performance. Therefore, a partially steel-reinforced precast concrete (PSPC) beam with an embedded H-beam was developed to combine the merits of both the prefabrication in the precast concrete beam and the quick assembly in the steel beam. In this study, the developed beam was proposed to connect the concrete encased CFST column with a reduced beam section. A half-scaled frame substructure specimen with two floors and two bays was designed and tested under the cyclic loading to investigate the seismic performance. A series of seismic properties were analyzed, including the failure phenomena, hysteretic performance, stiffness degradation, and energy dissipation capacity. The dog-bone configuration was found to benefit the beam hinge failure mechanism and an acceptable deformation capacity (the ductility coefficient up to 2.77). The function of the H-beam contributed to stable energy absorption (the equivalent damping coefficient from 0.33 to 0.37). Finally, the proposed frame was compared with a reinforced concrete frame and a steel-reinforced concrete frame through numerical analysis. The partial steel-reinforced configuration had a positive influence on the bearing capacity, hysteretic performance, and safety storage. In addition, it could improve the cost-effectiveness with little decrease in the bearing capacity.

Toward Low‐Latency Estimation of Atmospheric CO2 Growth Rates Using Satellite Observations: Evaluating Sampling Errors of Satellite and In Situ Observing Approaches

AbstractThe atmospheric CO2 growth rate is a fundamental measure of climate forcing. NOAA's growth rate estimates, derived from in situ observations at the marine boundary layer (MBL), serve as the benchmark in policy and science. However, NOAA's MBL‐based method encounters challenges in accurately estimating the whole‐atmosphere CO2 growth rate at sub‐annual scales. Here we introduce the Growth Rate from Satellite Observations (GRESO) method as a complementary approach to estimate the whole‐atmosphere CO2 growth rate utilizing satellite data. Satellite CO2 observations offer extensive atmospheric coverage that extends the capability of the current NOAA benchmark. We assess the sampling errors of the GRESO and NOAA methods using 10 atmospheric transport model simulations. The simulations generate synthetic OCO‐2 satellite and NOAA MBL data for calculating CO2 growth rates, which are compared against the global sum of carbon fluxes used as model inputs. We find good performance for the NOAA method (R = 0.93, RMSE = 0.12 ppm year−1 or 0.25 PgC year−1). GRESO demonstrates lower sampling errors (R = 1.00; RMSE = 0.04 ppm year−1 or 0.09 PgC year−1). Additionally, GRESO shows better performance at monthly scales than the NOAA method (R = 0.76 vs. 0.47, respectively). Due to CO2's atmospheric longevity, the NOAA method accurately captures growth rates over 5‐year intervals. GRESO's robustness across partial coverage configurations (ocean or land data) shows that satellites can be promising tools for low‐latency CO2 growth rate information, provided the systematic biases are minimized using in situ observations. Along with accurate and calibrated NOAA in situ data, satellite‐derived growth rates can provide information about the global carbon cycle at sub‐annual scales.

Reusing d-DNNFs for Efficient Feature-Model Counting

Feature models are commonly used to specify valid configurations of a product line. In industry, feature models are often complex due to numerous features and constraints. Thus, a multitude of automated analyses have been proposed. Many of those rely on computing the number of valid configurations, which typically depends on solving a #SAT problem, a computationally expensive operation. Even worse, most counting-based analyses require evaluation for multiple features or partial configurations resulting in numerous #SAT computations on the same feature model. Instead of repetitive computations on highly similar formulas, we aim to improve the performance by reusing knowledge between these computations. In this work, we are the first to propose reusing d-DNNFs for performing repetitive counting queries on features and partial configurations. In our experiments, reusing d-DNNFs saved up-to \(\sim\) 99.98% compared to repetitive invocations of #SAT solvers even when including compilation times. Overall, our tool ddnnife combined with the d-DNNF compiler d4 appears to be the most promising option when dealing with many repetitive feature-model counting queries.

Formulation analysis and follow-up study of multi-turn configuration for performance enhancement of MEMS piezoresistive pressure sensor utilized for low-pressure measurement applications

PurposeThe purpose of this research is to study the performance of piezoresistive pressure sensors using polysilicon as the piezoresistive material, which is typically used to measure pressure in high-temperature environments.Design/methodology/approachThe performance of this sensor is enhanced by studying the influence of multi-turn configuration at which the piezoresistors are arranged. Different configurations are studied and compared by laying down their analytical solution.FindingsThe validation of analytical results is accomplished through finite element analysis using the software COMSOL Multiphysics. The best configuration, which uses a partial triple-turn configuration, was able to achieve a sensitivity of 116.00 mV/V/MPa over a simulated pressure range of 0 to 500 KPa.Originality/valueThe literature shows the study of single-turn and double-turn meander-shaped configuration of micro-electromechanical systems piezoresistive pressure sensor but multi-turn meander-shaped configuration using a square silicon diaphragm has not been reported. Its study has reflected promising results than its counterparts based on key performance parameters such as sensitivity and linearity and are more effective to be used for automotive, aviation, biomedical and consumer electronics applications.

Searches for neutrino counterparts of gravitational waves from the LIGO/Virgo third observing run with KM3NeT

The KM3NeT neutrino telescope is currently being deployed at two different sites in the Mediterranean Sea. First searches for astrophysical neutrinos have been performed using data taken with the partial detector configuration already in operation. The paper presents the results of two independent searches for neutrinos from compact binary mergers detected during the third observing run of the LIGO and Virgo gravitational wave interferometers. The first search looks for a global increase in the detector counting rates that could be associated with inverse beta decay events generated by MeV-scale electron anti-neutrinos. The second one focuses on upgoing track-like events mainly induced by muon (anti-)neutrinos in the GeV–TeV energy range. Both searches yield no significant excess for the sources in the gravitational wave catalogs. For each source, upper limits on the neutrino flux and on the total energy emitted in neutrinos in the respective energy ranges have been set. Stacking analyses of binary black hole mergers and neutron star-black hole mergers have also been performed to constrain the characteristic neutrino emission from these categories.

Review of DC-DC Partial Power Converter Configurations and Topologies

The Partial Power Processing (PPP) concept has garnered attention as it enables the down-sizing of converter and component ratings. Unlike conventional power processing, PPP addresses a portion of the transferred power, leading to a reduction in conversion losses. Throughout this paper, the state of the art of isolated and non-isolated DC-DC converter topologies will be revised. Partial Power Converter (PPC) systems represent one of the main streams of PPP, which, based on isolation requirements and converter connections, can further be divided into isolated converters, such as: Input-Parallel-Output-Series (IPOS), Input-Series-Output-Parallel (ISOP), and, Input-Series-Output-Series (ISOS), or non-isolated converters. This work intends to evaluate and differentiate the characteristics of each type of topology while developing analytically possible connections that may require further research and reviewing metrics that help in fair comparisons of different PPC arrangements, operating under different conditions. A thorough revision is provided for DC-DC converter topologies due to their increased importance in present-day applications, such as energy storage, Electric Vehicles (EVs), and Photo-Voltaics (PVs).

Localized General Vertical Coordinates for Quasi‐Eulerian Ocean Models: The Nordic Overflows Test‐Case

AbstractA generalized methodology to deploy different types of vertical coordinate system in arbitrarily defined time‐invariant local areas of quasi‐Eulerian numerical ocean models is presented. After detailing its characteristics, we show how the general localization method can be used to improve the representation of the Nordic Seas overflows in the UK Met Office NEMO‐based eddy‐permitting global ocean configuration. Three z*‐levels with partial steps configurations localizing different types of hybrid geopotential/terrain‐following vertical coordinates in the proximity of the Greenland‐Scotland ridge are implemented and compared against a control configuration. Experiments include a series of idealized and realistic numerical simulations where the skill of the models in computing pressure forces, reducing spurious diapycnal mixing and reproducing observed properties of the Nordic Seas overflows are assessed. Numerical results prove that the localization approach proposed here can be successfully used to embed terrain‐following levels in a global geopotential levels‐based configuration, provided that the localized vertical coordinate chosen is flexible enough to allow a smooth transition between the two. In addition, our experiments show that deploying localized terrain‐following levels via the multi‐envelope method allows the crucial reduction of spurious cross‐isopycnal mixing when modeling bottom intensified buoyancy driven currents, significantly improving the realism of the Nordic Seas overflows simulations in comparison to the other configurations. Important hydrographic biases are found to similarly affect all the realistic experiments and a discussion on how their interaction with the type of localized vertical coordinate affects the realism of the simulated overflows is provided.

Effect of partial cooling-heating configurations on the enhanced latent thermal energy storage performance

A low rate of ice melting can be addressed by adding nanoscale particles of high thermal conductivity; however, other simple and effective techniques are also possible for further enhancement of the thermal characteristics and melting process of ice as well as other phase storage materials for thermal energy storage. In the present numerical study, two techniques combining partial heating and inversion of the active cavity walls in addition to adding hybrid nanoparticles (Cu and Al2O3) are investigated for the sake of enhancing the phase change in the cavity. Modeling is based on Lattice-Boltzmann techniques; numerical predictions are successfully compared with experimental and theoretical published data. The thermal behavior of the enhanced phase change material is analyzed for various Rayleigh and Fourier numbers and nanoparticle concentrations. The isotherms, streamlines, interface position, liquid fraction evolution, and full melting duration are analyzed. The outcomes show that for each concentration investigated, there is a different best configuration for reducing the ice melting time. 76% reduction in the melting time was achieved with a nanoparticle concentration of 6% (hybrid copper and alumina) and proper simultaneous heating and cooling configuration. These findings can guide designing efficient ice-based systems.

C-band Hexagon Slotted Textile Antenna Design with Jeans Substrate for Satellite Communication Applications

This paper presents the design of a hexagonal slotted circular flexible textile microstrip patch antenna that is used for C-band satellite communication applications. In the proposed antenna design, a textile material blue Jeans fabric with relative permittivity 1.67, loss tangent of 0.01 and the thickness of 1 mm is used as the substrate with an overall dimension of 40×38 mm2. The textile material is used as it is washable, wearable, flexible and very economical. Self-adhesive Copper tape is used to make the patch and ground of the antenna that is fed through a microstrip inset feed line. The proposed antenna contains a hexagonal-shaped slot on the patch and a partial ground configuration for getting better bandwidth and gain. The antenna has been designed and simulated using CST microwave Studio software. The simulated antenna performance parameters like return loss, bandwidth, VSWR, gain, efficiency, radiation pattern and surface current are presented. The antenna is resonating at 4.28 GHz and operating in the frequency range of 2.91 -5.2 GHz, with reflection coefficient of -24.42 dB, and a bandwidth of 2.29 GHz. The peak gain of the antenna is 3.42 dBi and radiation efficiency of 87.3% at 4.2 GHz. The proposed antenna covers C-band and with its compact size, wearability and wide bandwidth capabilities, the antenna proves to be a suitable candidate for C-band satellite communication applications.

Environmental control system (ECS) design approach for collective nuclear, biological, and chemical (NBC) protection in military aircraft: A review

This comprehensive review paper delves into Environmental Control System (ECS) design strategies tailored for collective Nuclear, Biological, and Chemical (NBC) protection in military aircraft, exploring key elements such as hardening, air-tight construction, and filtering within the framework of open-loop or closed-loop ECS configurations. Initially, the paper elucidates the NBC protection requirements stipulated in commonly applied regulations such as MIL-HDBK-516C, DEFSTAN, and EMACC, highlighting the imperative for ventilation air to be devoid of contaminants, as mandated by these regulations. Subsequently, the paper delineates the strategic framework for NBC defense in the military aerospace industry, emphasizing the principles of avoidance, protection, and decontamination. A comparative analysis between individual and collective protection strategies underscores the comprehensiveness of the latter, prompting a recommendation for ECS design approaches grounded in the principles of collective protection, namely hardening, air-tight construction, and filtering. Furthermore, the paper provides insights into the configurations of open-loop and partial closed-loop ECS, elucidating their architectures for NBC protection. A comparative evaluation of these configurations enables the identification of pertinent parameters crucial for informed selection. In conclusion, the paper posits that the partial closed-loop ECS configuration exhibits greater promise in delivering enhanced NBC protection compared to the open-loop configuration, particularly in military aircraft applications operating in NBC environments.

PERFORMANCE ANALYSIS OF P&O AND PSO MPPT ALGORITHMS FOR PV SYSTEMS UNDER PARTIAL SHADING

Photovoltaic (PV) modules are devices that transform photon energy into electrical energy. The output power of the PV modules is influenced by the intensity of solar radiation and the ambient temperature. Non-uniform shading can cause variations in the extent of sunlight absorbed by PV modules, resulting in a decrease in power output. Maximum power point tracking (MPPT) techniques are employed to optimize the power output of PV modules by operating them at their maximum power point (MPP). The main objective of the study is to investigate the performance analysis of Perturb and Observe (P&O) and Particle Swarm Optimization (PSO) MPPT strategies in uniform and partially shaded conditions with equally and unequally different irradiance differences. Simulation studies were conducted on the PV circuit model using Matlab/Simulink, and the results were evaluated. MPPT algorithms are compared based on their tracking efficiency and convergence speed when solar radiation conditions vary. The findings of the simulation indicate that the P&O is unable to determine global MPP and gets trapped in one of the local MPPs. However, the PSO is very effective in tracking MPP under different partial shading patterns with more than 96% tracking efficiency. In the first partial shading configuration where the sunlight intensity of the PV modules is uniformly distributed, the PSO technique has reduced steady-state oscillations around the MPP. However, the P&O technique demonstrates superior response time and convergence speed in comparison to the PSO technique.

Experimental study of partially encased bamboo scrimber columns under axial compression

ABSTRACT Both bamboo scrimber and section steel are extensively employed in the construction industry however bamboo scrimber as a large composite member, easily experiences buckling and splitting under compression. To solve the problem of insufficient bearing capacity, a partially encased bamboo scrimber (PEBS) column was developed in this paper, and the PEBS column consisted of an H-shaped steel member with two rectangular bamboo scrimber members placed inside the web and flanges, forming a partial buckling restraint configuration. The aim of this arrangement was to enhance the axial compressive performance of the bamboo scrimber members through partial lateral confinement. To investigate the influences of the composite effect and specimen size, a total of 45 specimens were tested under axial compression to analyse the failure modes, load–displacement relationships, and mechanical properties. The results revealed that the composite specimens ultimately failed owing to buckling and wedged splitting in the bamboo scrimber members. The partial buckling restraint exhibited a substantial improvement in axial bearing capacity through delaying the buckling of the H-shaped steel and failure of the inner bamboo scrimber, leading to a further enhancement in the safety stock. Finally, a calculation method was proposed to predict the ultimate bearing capacity of the PEBS column.

TAM VE PARÇALI SİLİNDİRİK KANATÇIK KONFİGÜRASYONLARININ BİR MİNİKANALLI ISI ALICININ TERMOHİDROLİK PERFORMANSI ÜZERİNDEKİ ETKİLERİ

In this numerical investigation, the impacts of complete and partial cylindrical fin configurations on the thermohydraulic performance of a minichannel heatsink are studied. ANSYS Fluent software is used to conduct numerical analyses for four distinct mass flow rates ranging from 0.00265 kg/s to 0.0045 kg/s and three distinct fin positions. The effects of various configurations on velocity and temperature fields, average Nusselt number, Nusselt number ratio, friction coefficient, and performance evaluation coefficient are analyzed. According to the study’s findings, using partial cylindrical fins has a substantial impact on both heat transfer and pressure drop. When evaluating heat transfer, MCHS-R2a produces the greatest results, but this configuration greatly raises flow resistance. MCHS-R2c was found to have substantial potential when evaluated in terms of thermohydraulic performance.

Onto-CARMEN: Ontology-driven approach for Cyber–Physical System Security Requirements meta-modelling and reasoning

In the last years, Cyber–physical systems (CPS) have attracted substantial mainstream, especially in the industrial sector, since they have become the focus of cyber-attacks. CPS are complex systems that encompass a great variety of hardware and software components with a countless number of configurations and features. For this reason, the construction, validation, and diagnosis of security in CPS become a major challenge. An invalid security requirement for the CPS can produce partial or incomplete configuration, even misconfigurations, and hence catastrophic consequences. Therefore, it is crucial to ensure the validation of the security requirements specification from the earlier design stages. To this end, Onto-CARMEN is proposed, a semantic approach that enables the automatic verification and diagnosis of security requirements according to the ENISA and OWASP recommendations. Our approach provides a mechanism for the specification of security requirements on top of ontologies, and automatic diagnosis through semantic axioms and SPARQL rules. The approach has been validated using security requirements from a real case study.

WTP5.9 Does anti-reflux surgery offer durable symptom remission in a tertiary centre?

Abstract Aims Anti-reflux surgery success can be affected by multiple factors. We sought to evaluate pre-operative and technical factors influencing medium-term outcomes. Methods A retrospective analysis of laparoscopic anti-reflux surgery in a tertiary centre between 2016 and 2019. Patients were identified through clinical coding. Electronic patient records were reviewed with minimum follow up of 3 years. Outcomes analysed included pre-operative work-up, type of fundoplication, remission and relapse of symptoms at follow up and revision surgery. Results 104 patients underwent fundoplication. The majority were Nissen 68 (65%) and the remaining were partial wrap configuration.18 (19%) of these patients were revisional anti-reflux procedures. Pre-operative investigations noted most underwent endoscopy 85 (81.7%) and oesophageal physiology in 74 (71.2%) with barium swallow in 34 (32.7%). 15/104 (14%) underwent all three studies. 50 (48.1%) patients were symptomatic at initial follow up with dysphagia (21.3%) and dyspepsia (13.5%) most prevalent. Of these 104 patients, 15 (14.4%) required revisional surgery. 6/36 (17%) partial and 9/68 Nissen (13.2%) fundoplications underwent re-operation. Timing of revision varied: 8 (53.3%) within one year including early 30-day re-operation for complications. 3 (20%) at 1-3years and 4 (26.7%) after 3 years. Subsequent revision rate was higher for revisional patients: 4/18 (22.2%) compared to primary 11/86 (12.7%). Conclusion Almost half of the patients had at least one symptom at initial follow up, however only 14.4% patients required revisional surgery by 3 years follow up. Partial fundoplication and previous fundoplication surgery had higher revision surgery rates.

Study of Unsteady Surface Flowfields on and Around Turrets with Different Protrusions

Wind-tunnel experiments were conducted to measure the unsteady surface pressure field on and around a hemisphere-on-cylinder turret of varying protrusion in subsonic flow. These measurements were obtained using fast-response pressure-sensitive paint coupled with pressure transducers. The surface pressure field data resulting from Mach 0.5 flow () over a partially submerged hemisphere, a hemisphere, and a hemisphere on a cylinder were analyzed using proper orthogonal decomposition modal analysis, as well as a variant of this approach referred to as joint proper orthogonal decomposition. The results showed that decreased turret protrusion into the freestream flow reduced the prevalence of antisymmetric surface pressure field fluctuations caused by antisymmetrical vortex shedding. The frequency associated with this fluctuation was found to be around . When a partial hemispherical turret geometry was used, it was shown that the antisymmetric mode was greatly suppressed; and the wake was dominated by a symmetric mode with a broadband spectral peak at a higher frequency of . This suggests that there is a “mode switching” as the protrusion is changed from the hemisphere to the partial hemisphere configuration. An optical flow approach was used to find the convective velocity field in the wake, from which topological flow features could be identified. The size of the wake separation region was found to grow smaller with the decreased protrusion while keeping a similar shape.

Topological encounters in biodiversity conservation: Making and contesting maps in the Colombian high Andean páramos

Páramos are one of the flagship ecosystems in the Northern Andes; the provision of water for millions of people in this region depends on these unique high mountains located at above 3,500 m of altitude. Besides, they are also the refuge of a rich biodiversity that is unique in the world, the conservation of which has become important in recent years. Human communities, such as campesino communities, have also inhabited some páramos. For example, in the Sumapaz region of central Colombia, campesino communities sought refuge in the páramos during the 20th century due to political violence. Since 2010, the Colombian government, following previous legislation and court sentences, has declared páramos “strategic ecosystems,” making their conservation a vital part of the environmental policy in the country. This was advanced through mapmaking as the tool to define clear-cut limits for human use, prohibiting mining, agriculture, and livestock in spaces demarcated as páramos. However, this made the conservation of the policy incompatible with the presence of campesinos living in páramos. Since then, their conservation in the Sumapaz region has been a contentious matter about what kind of páramos and biodiversity should be allowed and enacted in Colombia. As part of a two-year multi-sited ethnography with geographers and campesino communities in Sumapaz páramo, I developed a topological approach to study mapmaking practices in the context of biodiversity conservation. I argue that this can be a way to understand the diverse relations between humans and nature as partial space configurations that shape conservation practice and its forms of politics. With this social sciences contribution, I extend the mapmaking discussions in conservation that seek to open taken-for-granted notions of space that limit conservation possibilities for socioenvironmental change.

Recent progress in description of NN–scattering with the dibaryon model of nuclear forces

The recent results in description of elastic and inelastic nucleon-nucleon scattering within the dibaryon model of nuclear forces are reviewed. This original model taking into account non-nucleonic degrees of freedom is based on the special mechanism including an exchange by an intermediate six quark state. A good description of the partial phase shifts and inelasticities is found for the main lowest partial NN configurations in a wide energy range from zero up to 0.6–1 GeV. The model gives the resonances in each NN-configuration as well, the parameters of which are compared with the data found from recent experiments on single- and double-pion production and partial wave analysis.

Liver-cell protective pyridones from the fungi Tolypocladium album dws120

Five previously undescribed pyridone derivatives, tolypyridones I–M, were identified from the solid rice medium fermented by Tolypocladium album dws120, along with two known compounds tolypyridone A (or trichodin A) and pyridoxatin. Their planar structures and partial relative configurations have been determined by careful interpretation of their spectroscopic data. The full assignment of the relative and absolute configurations of tolypyridones I–M was achieved by gauge-independent atomic orbital 13C NMR calculation, quantitative nuclear Overhauser effects based interatomic distance calculation, and electronic circular dichroism calculation. In addition, we have fully determined the configuration of tolypyridone A by X-ray diffraction analysis. In bioassay, tolypyridones I was able to restore cell viability and inhibit the release of alanine aminotransferase and aspartate aminotransferase for ethanol-induced LO2 cells, suggesting its potential as a liver protective agent.