Performance Analysis Research Articles

Performance analysis of a 1 MW reversible solid oxide system for flexible hydrogen and electricity production

Performance analysis of a 1 MW reversible solid oxide system for flexible hydrogen and electricity production

Joint satellite platform and constellation sizing for instantaneous beam-hopping in 5G/6G Non-Terrestrial Networks

Existing research on resource allocation in satellite networks incorporating beam-hopping (BH) focuses predominantly on the performance analysis of diverse algorithms and techniques. However, studies evaluating the architectural and economic impacts of implemented BH-based technical solutions have not yet been addressed. Aiming to close this gap, this contribution quantifies the impact of BH and orbital parameters on the satellite platform and constellation size, considering specific traffic demand and service time indicators. The paper proposes a low complexity, instantaneous demand-based BH resource allocation technique, and presents a comprehensive analysis of LEO and VLEO scenarios using small platforms, lying on 5G/6G Non-Terrestrial Network (NTN) specifications. Given a joint set of traffic demand and time-to-serve indicators, and based on a feasible multibeam on-board antenna architecture, the paper compares the RF transmit power requirements in fixed and variable grid LEO schemes, and in VLEO with different minimum elevation angles, to assess the feasibility of these orbits. For a fixed minimum elevation and number of users, the RF transmit power and satellite platform requirements are significantly reduced when transitioning into lower altitudes with narrower satellite coverage areas. The relevant trade-off between the satellite platform and the size of the constellation required for global coverage is presented, to fulfill a set of traffic demand and time to serve indicators: approximately, 1156 3U satellites are required for VLEO constellation and 182 12U satellites for LEO. Once platform and constellation sizing trade-off is quantified, the paper estimates the economic costs for each of the deployments, showing a total cost of almost the double for the presented VLEO constellation compared to the LEO one. The article aims to provide system engineers and satellite operators with crucial information for satellite system design, dimensioning and cost assessment.

Performance Analysis for STAR-RIS-Assisted Wireless Powered Communications With Cooperative Jamming

Performance Analysis for STAR-RIS-Assisted Wireless Powered Communications With Cooperative Jamming

6-DoF Pose Estimation from Single RGB Image and CAD Model Retrieval Using Feature Similarity Measurement

This study presents six degrees of freedom (6-DoF) pose estimation of an object from a single RGB image and retrieval of the matching CAD model by measuring the similarity between RGB and CAD rendering images. The 6-DoF pose estimation of an RGB object is one of the important techniques in 3D computer vision. However, in addition to 6-DoF pose estimation, retrieval and alignment of the matching CAD model with the RGB object should be performed for various industrial applications such as eXtended Reality (XR), Augmented Reality (AR), robot’s pick and place, and so on. This paper addresses 6-DoF pose estimation and CAD model retrieval problems simultaneously and quantitatively analyzes how much the 6-DoF pose estimation affects the CAD model retrieval performance. This study consists of two main steps. The first step is 6-DoF pose estimation based on the PoseContrast network. We enhance the structure of PoseConstrast by adding variance uncertainty weight and feature attention modules. The second step is the retrieval of the matching CAD model by an image similarity measurement between the CAD rendering and the RGB object. In our experiments, we used 2000 RGB images collected from Google and Bing search engines and 100 CAD models from ShapeNetCore. The Pascal3D+ dataset is used to train the pose estimation network and DELF features are used for the similarity measurement. Comprehensive ablation studies about the proposed network show the quantitative performance analysis with respect to the baseline model. Experimental results show that the pose estimation performance has a positive correlation with the CAD retrieval performance.

Performance analysis of IRI-2016 and IRI-2020 models, and GPS and GLONASS-TEC variations, and their predictions using Artificial Neural Networks (ANNs) at low latitude station Agra, India

Performance analysis of IRI-2016 and IRI-2020 models, and GPS and GLONASS-TEC variations, and their predictions using Artificial Neural Networks (ANNs) at low latitude station Agra, India

Development and performance analysis of cold storage systems utilising aluminum oxide (Al2O3) nanoparticle-enhanced phase change materials integrated with photovoltaic solar energy

Development and performance analysis of cold storage systems utilising aluminum oxide (Al2O3) nanoparticle-enhanced phase change materials integrated with photovoltaic solar energy

Machine learning-based optimization and dynamic performance analysis of a hybrid geothermal-solar multi-output system for electricity, cooling, desalinated water, and hydrogen production: A case study

Machine learning-based optimization and dynamic performance analysis of a hybrid geothermal-solar multi-output system for electricity, cooling, desalinated water, and hydrogen production: A case study

Performance analysis of a turbofan engine integrated with flame-assisted fuel cells for combined propulsion and power generation with more electric aircrafts

Performance analysis of a turbofan engine integrated with flame-assisted fuel cells for combined propulsion and power generation with more electric aircrafts

Design and performance analysis of a low-cost monitoring system for advanced building envelopes

The objective of this study is to design a low-cost system for long-term monitoring of advanced building envelope and evaluates its performance in comparison to conventional lab-grade sensors. Leveraging the potentials of a single-board computer and several low-cost digital sensors, the system measured thermo-physical and environmental parameters, including temperature, humidity, CO2 levels, airflow rate, lighting, and heat flux. The system's architecture allowed for easy integration and flexible connectivity, providing comprehensive monitoring capabilities at a fraction of the cost of lab-grade systems. A basic prototype is available in a GitHub repository. The systematic evaluation of the proposed concept involved three key experiments using a double-skin façade mockup installed in a full-scale climate simulator. Sensor accuracy over 24 hours was assessed through time-series comparison, showing high accuracy in recording air temperature, humidity, and surface temperature without on-site calibration, though calibration was essential for precise CO2 and lighting measurements. Key performance indicators of the thermophysical behavior of envelope systems, such as U-value and g-value, were derived for both the low-cost and lab-grade setups. Discrepancies of up to 7% in U-value and 13% in g-value were observed, confirming the system's reliability for building energy assessments. Additionally, the low-cost system effectively represented dependencies between independent and dependent variables, as shown by analysis of variance, closely aligning with the picture obtained from lab-grade sensors’ data. These findings validate the low-cost monitoring system as a viable, cost-effective alternative for advanced building envelope performance studies and indoor environmental quality assessments, highlighting the need for calibration of certain sensors.

Innovative design and performance analysis of a Static Shaft Wankel Expander for Micro-Scale Organic Rankine Cycles

Innovative design and performance analysis of a Static Shaft Wankel Expander for Micro-Scale Organic Rankine Cycles

Thermal performance analysis of a deep coaxial borehole heat exchanger with a horizontal well based on a novel semi-analytical model

This study introduces a novel semi-analytical model for deep coaxial borehole heat exchanger with a horizontal well(H-DBHE), which incorporates the effects of formation stratification and transient heat conduction within the pipe walls. Initially, the model's validity was checked through a comparison with the results derived from the published numerical models. This semi-analytical approach significantly reduces computational time while ensuring calculation accuracy. Subsequently, the study quantitatively examined the influence of the operation parameters, structural characteristics and the thermal capacity within the borehole on the dynamic heat extraction of H-DBHE. The numerical results demonstrate that the thermal capacity within the borehole significantly influences the heat extraction performance during intermittent operations of H-DBHE. Based on this finding, the study further investigated the effects of intermittent operation and heating time on the heat recovery performance of the system. Additionally, the study compared the long-term operational performance and thermal attenuation between H-DBHE and deep coaxial borehole heat exchanger (DBHE) over a ten-year simulation period. This research introduces a novel semi-analytical model for H-DBHE, which is of significant theoretical guidance for accurately predicting the heat extraction performance of H-DBHE and scientifically designing geothermal utilization systems.

Characterization and performance analysis of modified phase change material with paraffin wax and waste exhaust carbon particles for thermal energy storage

Characterization and performance analysis of modified phase change material with paraffin wax and waste exhaust carbon particles for thermal energy storage

Controlled Wireless Channel using Multi-Antenna Multi-IRS Assisted Communication System: A Comprehensive Performance Analysis

Controlled Wireless Channel using Multi-Antenna Multi-IRS Assisted Communication System: A Comprehensive Performance Analysis

Performance analysis of recuperated Brayton pumped thermal electricity storage with staged compressors

Performance analysis of recuperated Brayton pumped thermal electricity storage with staged compressors

Experimental pool boiling heat transfer performance analysis on novel two-stage hybrid aligned copper oxide nanowires that stand independently and one over the other (nanowires on nanowires) surfaces

Experimental pool boiling heat transfer performance analysis on novel two-stage hybrid aligned copper oxide nanowires that stand independently and one over the other (nanowires on nanowires) surfaces

Microemulsification-based hybrid oxygenated biofuel for CI engine locomotives: with special reference to "preparation" techniques and "performance" analysis.

In recent years, rising environmental concerns and the detrimental impact of emissions from the growing number of locomotives have prompted scientists to investigate alternative fuels derived from renewable lipids, such as microemulsion-based hybrid biofuels (MHBFs). Petro crops and lignocellulosic biomass are the common agricultural and forest feedstocks for biofuel production. Biofuel can be characterized in terms of its volatility range, physicochemical properties, composition, combustion, and emission characteristics. This paper elaborated on the petrodiesel-like oxygenated biofuel obtained from different feedstocks, their preparation, and performance analysis viz. the microemulsion-based hybrid oxygenated biofuel. In this paper, preparation steps such as the microemulsion type, concentration ratio, microemulsion component, surfactant, and phase separation of microemulsion as well as the basic precautions to form a stable microemulsion have been addressed. The analysis of performance, emissions, and overall efficiency of especially locomotive compression ignition (CI) engines has been extensively studied across various combustion engine types. MHBF is a multi-component biofuel system, consisting of ethanol, butanol, vegetable oil, and many other combustible liquid and fuel fractions as available in the literature. The engine performance metrics, specifically brake thermal efficiency and brake-specific fuel consumption, have been evaluated and show that these values are comparable between biodiesel blends, petrodiesel, and pure petrodiesel. Various researchers have reported that emissions, particularly CO and NOx, are significantly lower when using MHBF compared to biodiesel and petrodiesel. The review suggests that MHBF has the potential to eventually replace other renewable liquid fuel formulations for CI engines due to its simple preparation process.

FPGA-Based Chaotic Oscillator Designs and Performance Analysis

FPGA-Based Chaotic Oscillator Designs and Performance Analysis

A new proposal for an easy-to-calibrate DNI clear-sky model: a performance analysis and validation in different geographical locations

Clear sky models can be used as a reference for sizing solar technology applications and for solar irradiance forecasting purposes. Properly defining the parameters of each clear sky model implies knowing the altitude, latitude, longitude, as well as various climatic characteristics of the study site, which makes its implementation difficult. Derived from the above, in this work a new easy-calibration methodology was developed to obtain a functional clear sky model for any day of the year and any geographical location. By proposing calibration coefficients obtained from only a couple of DNI measurements, and without taking into account the geographical characteristics or climatic conditions of the study site, the developed clear sky model was tested in a global context using a period of 11 years (2010-2020) with databases of 71 solarimetric stations, obtaining an average RMSD that ranges between 6.48% (arid climate) to 7.97% (equatorial climate). In addition, the developed model was compared with a variety of clear sky models to determine the percentage of accuracy of these against clear and non-clear sky days, thus demonstrating that the accuracy of the proposed model can be superior in different scenarios.

Financial Performance Measurement and Analysis in Quick Service Restaurant

Abstract: This paper presents a comprehensive review of Power BI to analyze the financial and operational performance of a large fast-food chain in India, specifically in the Quick Service Restaurant (QSR) sector. It starts by explaining the company’s structure and then focuses on analyzing its financial data, such as financial statements, budgeting, and future projections, tailored tothe needs of the QSR industry. Key to the analysis is organizing and cleaning data, creating unique product IDs, and ensuring accuracy for budget comparisons. The project covers in-depth data manipulation and modeling to ensure reliable insights into key financial metrics, such as revenue and profit. Advanced visualizations, including charts and Pareto analysis, help present a clear picture of the company’s performance. This research paper offers a detailed approach for using Power BI in the QSR sector, providing insights for improving business operations and profitability.

External driver of corporate green innovation: Does customer environmental concern matter?

PurposeThe purpose of this study is to examine the impact of customers' environmental concern on corporate green innovation and its underlying mechanisms.Design/methodology/approachThis study empirically examines the impact of customer environmental concern on corporate green innovation using 967 company-customer-year observations of Chinese A-share listed companies over the period 2012–2022.FindingsThe empirical results show that customer environmental concern significantly enhances corporate green innovation. Furthermore, executive environmental awareness and research and development (R&D) investment play a partial mediating role in this relationship. The heterogeneity analysis reveals that state-owned customers, customers located in the same province with the corporate and the intellectual property model cities contribute to strengthening this relationship. Moreover, corporate performance analysis shows that customer environmental concern can significantly increase corporate financial performance and sustainable performance.Originality/valueThis study innovatively proposes a measure of customer environmental concern and examines its impact on corporate green innovation and its underlying mechanisms. In addition, this study also proposes some insights for policymakers.