Design Performance Assessment Research Articles

Research advances in solar dryer technologies integrated with solar air heater: a state-of-the art review on design variations, performance and feasibility assessments

Research advances in solar dryer technologies integrated with solar air heater: a state-of-the art review on design variations, performance and feasibility assessments

H∞ optimum design and nonlinear seismic performance assessment of tuned-mass-damper-inerter (TMDI) supported by an auxiliary structure

Tuned Mass Damper Inerter (TMDI) and its simplified form, Tuned Inerter Damper (TID), are highly effective in mitigating seismic responses in buildings, particularly when rigidly connected to the ground. However, practical constraints often limit the feasibility of this ideal setup. This study introduces a novel configuration: the AS-type TMDI, which connects the TMDI to an auxiliary structure (AS) adjacent to the main building to simulate a ground connection. To design the AS-type TMDI, this research builds upon insights from studies on TMDIs in adjacent buildings and develops an analogous 3-DOF model representing the TMDI-linked adjacent-building system. This model incorporates two buildings of different heights, allowing the TMDI to be connected at any floor level. Utilizing fixed-point theory, the study derives an analytical solution for the optimal design of TMDI systems within this novel configuration. Additionally, a method is introduced to determine the optimal stiffness and design procedure for the AS itself. The performance of the proposed AS-type TMDI is evaluated through comprehensive nonlinear seismic analysis of a benchmark nine-story steel frame structure, accounting for material and geometric nonlinearities. Results demonstrate that the AS-type TMDI performs comparably to a virtually grounded TMDI in effectively reducing the seismic responses. Furthermore, this innovative configuration outperforms both a conventional retrofitting technique, where the building is rigidly connected to the AS, and a system where a viscous damper alone connects the main building to the AS. This highlights the AS-type TMDI's potential to significantly improve the building’s seismic performance.

Design and simulation of solar pumping system using PVsyst, case study: TSABIT - ADRAR in Algeria

In isolated sites, the extension of the electricity network requires a very high capital cost. For agriculture work, irrigation is a necessity. A possible solution is using renewable energy sources like solar power, which is environmentally friendly and available for free. This paper presents the design and simulation of a photovoltaic water pumping system for irrigation of a farm located at a place named Tsabit in Adrar southwest Algeria. A detailed approach for the design of an optimized PV water pumping system based on real water usage data is proposed. Besides, system design work and performance assessment were carried out based on hourly climatic conditions. PV SYST software is used to carry out this work. A comparison was also made between two water pumping systems with and without use of a sun tracker. From the obtained results, the use of this kind of system could have an important contribution in the social and economic development of a country, especially in the presence of a sun tracker device, where we recorded more efficiency.

Small planar antenna array design using length and spacing through Matlab‐HFSS interfacing

SummaryThis study presents a novel method for reducing return loss and achieving lower side lobe levels in small planar antenna arrays (PAAs). Quantum particle swarm optimisation (QPSO) findings are utilised for antenna design modelling and performance assessment utilising the MATLAB‐based moment's code approach and MATLAB‐HFSS interface. The mutual coupling between antenna components is considered and computed using the method of moments (MoM). Changing the array elements' length and spacing will accomplish the abovementioned objectives. The Matlab‐based moments code calculates the antenna components' length and spacing, and the antennas' length and spacing are used to produce the radiation pattern via the Matlab‐HFSS interface. Four examples of small PAA designs are given to illustrate how well the applied methodology works. The method discussed in this paper is generic and can be employed in the future for different sizes of the array elements and the different antenna array structure designs.

Implementation of a High-Sensitivity Global Navigation Satellite System Receiver on a System-on-Chip Field-Programmable Gate Array Platform.

This paper presents the design, proof-of-concept implementation, and preliminary performance assessment of an affordable real-time High-Sensitivity (HS) Global Navigation Satellite System (GNSS) receiver. Specifically tailored to capture and track weak Galileo E1b/c signals, this receiver aims to support research endeavors focused on advancing GNSS signal processing algorithms, particularly in scenarios characterized by pronounced signal attenuation. Leveraging System-on-Chip Field-Programmable Gate Array (SoC-FPGA) technology, this design merges the adaptability of Software Defined Radio (SDR) concepts with the the robust hardware processing capabilities of FPGAs. This innovative approach enhances power efficiency compared to conventional designs relying on general-purpose processors, thereby facilitating the development of embedded software-defined receivers. Within this architecture, we implemented a modular GNSS baseband processing engine, offering a versatile platform for the integration of novel algorithms. The proposed receiver undergoes testing with live signals, showcasing its capability to process GNSS signals even in challenging scenarios with a carrier-to-noise density ratio (C/N0) as low as 20 dB-Hz, while delivering navigation solutions. This work contributes to the advancement of low-cost, high-sensitivity GNSS receivers, providing a valuable tool for researchers engaged in the development, testing, and validation of experimental GNSS signal processing techniques.

Numerical Simulation of Heat Pipe Thermal Performance for Aerospace Cooling System Applications

The design of integrated and highly efficient solutions for thermal management is a key capability for different aerospace products, ranging from civil aircraft using hydrogen on board to miniaturized satellites. In particular, this paper discloses a novel numerical tool for the design and thermal performance assessment of heat pipes. To achieve this goal, a numerical Ansys Parametric Design Language code is set up to verify the effective subtractive heat flux guaranteed by the selected heat pipe arrangement. The methodology and related tool show their ability to provide good thermal performance estimates for different heat pipe designs and operating conditions. Specifically, the paper reports two very different test cases: (1) solid metal heat pipes to cool down the crotch leading-edge area of the air intake of a Mach 8 civil passenger aircraft, and (2) a copper-water heat pipe to cool down a Printed Circuit Board of a generic small LEO satellite. The successful application of the methodology and numerical code confirms the achievement of the ambitious goal of developing in-house tools to support heat pipe thermal performance prediction for the entire aerospace domain.

Supercritical CO2 Cycles for Nuclear-Powered Marine Propulsion: Preliminary Conceptual Design and Off-Design Performance Assessment

Supercritical CO2 Cycles for Nuclear-Powered Marine Propulsion: Preliminary Conceptual Design and Off-Design Performance Assessment

A Machine Learning-Based Approach to Evaluate the Spatial Performance of Courtyards—A Case Study of Beijing’s Old Town

The quality of residential buildings in old urban areas of Beijing is known to be inconsistent, prompting numerous urban renewal projects in the city. This research investigates how building space impacts energy usage and daylighting in courtyard areas of old urban regions in northern China. It also proposes a quick evaluation method for building performance in courtyard spaces, utilizing multi-objective optimization and machine learning classification prediction as a theoretical framework. A study was conducted to gather and organize building space parameters and their corresponding performances using a genetic algorithm. The dataset was then pre-processed and trained using the LightGBM algorithm. The model validation results revealed a recall of 0.9 and an F1-score of 0.8. These scores indicate that the design scheme’s performance level can be accurately identified in practical use. The goal of this study is to propose a set of rapid assessment methods for building performance levels in courtyard spaces. These methods can significantly improve the feedback efficiency between design decision and performance assessment, reduce the time wasted in building performance simulation during the architectural design process, and avoid unreasonable renovation and addition in urban renewal. Furthermore, the research method has universality and can be applied to courtyard-shaped buildings in other regions.

Characterization of Risk Prediction Models for Acute Kidney Injury

Despite the expansion of published prediction models for acute kidney injury (AKI), there is little evidence of uptake of these models beyond their local derivation nor data on their association with patient outcomes. To systematically review published AKI prediction models across all clinical subsettings. MEDLINE via PubMed (January 1946 to April 2021) and Embase (January 1947 to April 2021) were searched using medical subject headings and text words related to AKI and prediction models. All studies that developed a prediction model for AKI, defined as a statistical model with at least 2 predictive variables to estimate future occurrence of AKI, were eligible for inclusion. There was no limitation on study populations or methodological designs. Two authors independently searched the literature, screened the studies, and extracted and analyzed the data following the Preferred Reporting Items for Systematic Review and Meta-analyses guideline. The data were pooled using a random-effects model, with subgroups defined by 4 clinical settings. Between-study heterogeneity was explored using multiple methods, and funnel plot analysis was used to identify publication bias. C statistic was used to measure the discrimination of prediction models. Of the 6955 studies initially identified through literature searching, 150 studies, with 14.4 million participants, met the inclusion criteria. The study characteristics differed widely in design, population, AKI definition, and model performance assessments. The overall pooled C statistic was 0.80 (95% CI, 0.79-0.81), with pooled C statistics in different clinical subsettings ranging from 0.78 (95% CI, 0.75-0.80) to 0.82 (95% CI, 0.78-0.86). Between-study heterogeneity was high overall and in the different clinical settings (eg, contrast medium-associated AKI: I2 = 99.9%; P < .001), and multiple methods did not identify any clear sources. A high proportion of models had a high risk of bias (126 [84.4%]) according to the Prediction Model Risk Of Bias Assessment Tool. In this study, the discrimination of the published AKI prediction models was good, reflected by high C statistics; however, the wide variation in the clinical settings, populations, and predictive variables likely drives the highly heterogenous findings that limit clinical utility. Standardized procedures for development and validation of prediction models are urgently needed.

Design and Preliminary Performance Assessment of a PHM System for Electromechanical Flight Control Actuators

The evolution toward “more electric” aircraft has seen a decisive push in the last decade due to growing environmental concerns and the development of new market segments (flying taxis). Such a push has involved both the propulsion components and the aircraft systems, with the latter seeing a progressive trend in replacing traditional solutions based on hydraulic power with electrical or electromechanical devices. Flight Control Systems (FCSs) are one of the aircraft systems affected the most since the adoption of Electromechanical Actuators (EMAs) would provide several advantages over traditional electrohydraulic or mechanical solutions, but their application is still limited due to their sensitivity to certain single points of failure that can lead to mechanical jams. The development of an effective and reliable Prognostics and Health Management (PHM) system for EMAs could help in mitigating the risk of a sudden critical failure by properly recognizing and tracking the ongoing fault and anticipating its evolution, thus boosting the acceptance of EMAs as the primary flight-control actuators in commercial aircraft. The paper is focused on the results of the preliminary activities performed within the CleanSky 2/Astib research program, dedicated to the definition of the iron bird of a new regional-transport aircraft able to provide some prognostic capabilities and act as a technological demonstrator for new PHM strategies for EMAs employed in-flight control systems. The paper is organized as follows. At first, a proper introduction to the research program is provided, along with a brief description of the employed approach. Hence the simulation models adopted for the study are presented and used to build synthetic databases to inform the definition of the PHM algorithm. The prognostic framework is then presented, and a preliminary assessment of its expected performance is discussed.

Rasch Analysis for Standards-Setting Appraisal of Competency Level-Based Performance on the Part of Instructors in Higher Education

This research aimed to examine higher education instructors’ performance assessment in determining the cut-off point by setting criteria on the Wright map from big data. It is followed by designing performance assessment standards and assessing their quality. A total of 603 instructors from a Thai public university were selected as participants. The researchers employed a design-based research method encompassing four phases: analyzing the results of the performance assessment, formulating the standards-setting appraisal, applying trial and quality inspection, and improving the standards-setting appraisal approach. Data were analyzed using the Rasch model and the Maximum Likelihood Estimation method. The results of the determination of the cut-off point in terms of assessing instructors’ performance indicated that there are four cut-off points in ascending order, specifically, -11.67, -2.68, 4.59, and 9.76. The standards-setting appraisal showed that the assessment criteria consisted of five score ranges converted from estimation competency parameters into the scale and raw scores, respectively. Even though the standards-setting appraisal was determined, the researchers found that the transition point with regard to determination will be accurate and consistent in terms of those instructors who are at a moderate to high competency level and not suitable for evaluating those at a low competency level. The standards-setting appraisal approach is relevant for use as a criterion for recruiting and selecting higher education instructors. It can also support the development of sustainable human capital. It implies that instructors must possess high core competencies to match the high demand for quality teaching.

Design and Experimental Performance Assessment of an Outer Rotor PM-Assisted SynRM for the Electric Bike Propulsion

Brushless dc motor (BLDCM) is a conventional machine type used in the electric bike (e-bike) industry due to its simple controllability and drive system. However, the fluctuating price and scarcity of NdFeB magnets used in BLDCMs, lower power density compared to ac machines, and high torque ripple have pushed researchers in industry and academia to investigate technology alternatives to BLDCMs in e-bike applications. Permanent magnet-assisted synchronous reluctance motor (PMaSynRM) is an attractive option to this end because of its adjustable reluctance torque component and the recent advancements in finite-element (FE)-based design algorithms and implementation. Not yet covered in the existing literature and industry reports for e-bike applications, an in-hub outer rotor PMaSynRM is designed in this article to improve the power density and reduce the torque ripple characteristics for replacing a 500-W commercial BLDCM. The designed PMaSynRM is fabricated and tested to validate the power density and torque ripple improvements compared to an existing Golden Motor MP2 BLDCM counterpart.

Seismic Performance of Internal Partition Walls with Slotted and Bracketed Head-Tracks

ABSTRACT This paper presents the concept, design, construction and seismic performance assessment of internal partition walls with novel slotted and bracketed head-track details. In the slotted head-track walls, the anchors connecting the wall to the slab above are intended to slide within the slot to accommodate the desired in-plane drifts. On the other hand, in the bracketed head-track walls, the story-drift demands are accommodated by sliding of the bolt and flexing of the plastic brackets attached to the slots. In this paper, bi-directional behaviour of a novel flexible bracket is experimentally characterised and a number of wall sub-assemblies with the slotted and bracketed connection details are tested under quasi-static cyclic loading to investigate their seismic performance. The walls with slotted details showed the first signs of damage requiring repair at 0.78% drift. In contrast, when brackets were attached to the slots, the wall remained intact up to 4% drift, demonstrating a superior seismic resiliency.

Novel process design and techno-economic simulation of methanol synthesis from blast furnace gas in an integrated steelworks CCUS system

A novel process design and techno-economic performance assessment for methanol synthesis from Blast Furnace Gas (BFG) is presented. Methanol synthesis using BFG as a feedstock, based on direct CO2 hydrogenation at commercial scale was simulated using Aspen Plus software to evaluate its technical performance and economic viability. The applied process steps involve first conditioning BFG using adsorption based desulfurisation, water-gas shift, dehydration, then separation of components into N2, CO2 and H2 rich streams using pressure swing adsorption. The H2 stream and a fraction of the CO2 stream are fed to a methanol synthesis system, while the remaining CO2 may be considered for geological storage in a Carbon Capture, Utilization and Storage (CCUS) case, or not in a Carbon Capture Utilization (CCU) case. Techno-economic analysis confirms methanol production from BFG is economically attractive under certain conditions, with Levelized Cost of Methanol production (LCOMeOH) calculated to be 344.61 £/tonne-methanol, and costs of CO2 avoided of − 20.08 £/tonne-CO2 for the CCU process and 9.01 £/tonne-CO2 for the CCUS process when using a set of baseline engineering assumptions. Sensitivity analysis of the process simulation explores opportunities for optimising the methanol synthesis system in terms of the impact of reactor size and/or recycle ratio on LCOMeOH. Economic viability of the CCU(S) processes is also found to be highly dependent on the cost of the feedstock BFG. Future cost savings as compared to business-as-usual steel production by 2030 in consideration of expected increases in the carbon price are estimated to be 10.59 £/tonne-steel for CCU and 24.61 £/tonne-steel for CCUS.

Design guidelines for assessing students' interprofessional competencies in healthcare education: aconsensus study.

Healthcare systems require healthcare professionals and students educated in an interprofessional (IP) context. Well-designed assessments are needed to evaluate whether students have developed IP competencies, but we currently lack evidence-informed guidelines to create them. This study aims to provide guidelines for the assessment of IP competencies in healthcare education. Aqualitative consensus study was conducted to establish guidelines for the design of IP assessments using the nominal group technique. First, five expert groups (IP experts, patients, educational scientists, teachers, and students) were asked to discuss design guidelines for IP assessment and reach intra-group consensus. Second, one heterogeneous inter-group meeting was organized to reach aconsensus among the expert groups on IP assessment guidelines. This study yielded acomprehensive set of 26guidelines to help design performance assessments for IP education: ten guidelines for both the IP assessment tasks and the IP assessors and six guidelines for the IP assessment procedures. The results showed that IP assessment is complex and, compared to mono-professional assessment, high-quality IP assessments require additional elements such as multiple IP products and processes to be assessed, an IP pool of assessors, and assessment procedures in which standards are included for the IP collaboration process as well as individual contributions. The guidelines are based on expert knowledge and experience, but an important next step is to test these design guidelines in educational practice.

Thermal design and dynamic performance assessment of a hybrid energy system for an educational building

In this paper, according to the limitations of the cogeneration system in the off-design mode, four patterns are evaluated to meet the load demand of an educational building. In addition, to consider the government support policies in subsidizing energy carriers, the multi-production structure has been compared with a traditional system. The evaluation criteria in this analysis are the exergy efficiency, the relative net present worth benefit, and the relative net future worth benefit of the proposed design. The results show that the highest energy and exergy efficiencies are 55.33 % and 31 %, respectively, which are related to the following thermal load. The relative net present and future worth benefits are also 164,800 USD and 1.09 M USD, respectively. The highest relative net present and future worth benefits are 330,140 USD and 2.18 M USD for the peak load pattern. The results show that the following thermal load and peak load patterns are the best technical and economical options for the cogeneration system, respectively. Also, the best investment option with a rate of return of 37.9 % happened in the peak load pattern, which resulted in a 4.25 years payback period on the initial investment.

Receiver Sand Mitigation Measures along railways: CWE-based conceptual design and preliminary performance assessment

Desert railways are constantly exposed to incoming wind-blown sand. The railway structure locally disturbs the incoming sand drift, induces its accumulation, and ultimately suffers its harmful effects. Receiver Sand Mitigation Measures (SMMs) aerodynamically interact with the track system, induce sand erosion around it, and allow sand transport far downwind it. The conceptual and preliminary design of an innovative Receiver SMM called Sand Blower is developed in this study. The design is grounded on the aerodynamic behaviour of the baseline humped sleeper track system. The flow control strategy is intended to avoid boundary layer separation, and to promote local flow acceleration by means of the Venturi effect. The performance assessment is carried out by Computational Wind Engineering approach. It allows to simulate the local wind flow, to obtain the shear stress field at the wall, and to derive from it sand sedimentation, windward erosion and backward erosion conditions. The results show that the Sand Blower greatly increases the track system performance by reducing sand sedimentation and increasing sand erosion under wide range of wind speeds and directions.

Assessing Hydrological Cost-Effectiveness of Stormwater Multi-Level Control Strategies in Mountain Park under the Concept of Sponge City

Within the concept of sponge city in China, green stormwater measures have been widely used in urban mountain parks. This study provides an integrated assessment framework for hydrological cost-effectiveness in the Nanjing Guanyao Mountain Park under various precipitation scenarios. A grey drainage basic strategy and four multi-level control strategies with progressively increasing graded interception or storage facilities at mid-and terminal levels were designed and evaluated. Results show that the multi-level interception and storage strategy (S4) proved to be the most beneficial, followed by the multi-level interception strategy (S2) having slightly lower results than the multi-level storage strategy (S3), while the terminal strategy (S1) showed poor results. However, the hydrological cost-effectiveness exhibits the opposite trend under 2–5-year storms. A high multi-level strategy limited by life-cycle costs may not impart high hydrological cost-effectiveness in response to each return period of storms in this mountain stormwater practice. This study validates the hydrological performance and cost-effectiveness of multi-level distributed strategies in an urban mountain park, bridges the limitations of the previous studies on single scheme design and hydrological performance assessment for sloped sites, and provides a technical reference and design basis for similar studies and practices.

Applications of solar PV tree systems with different design aspects and performance assessment

ABSTRACT Solar energy is deemed as the most abundant, reliable, eco-friendly and totally free resource of energy. There is a wide range of techniques to harness solar energy for different purposes. Among all the available methods, direct conversion of sunlight into electricity through photovoltaic (PV) phenomenon is the most mature and popular process. Progress of PV technology in market is perspicuous; however, it has still some drawbacks such as notable land requirement in cities, energy conversion efficiencies that already reached the theoretical limits and social acceptance issues due to aesthetic details. To overcome the aforesaid challenges, solar PV tree concept has been recently developed, and the simplicity, compact structure and elegance of this novel technology have been in the focus of researchers. Within the scope of this review, the concept of solar PV tree has been extensively investigated in terms of various design aspects and potential applications. Current performance characteristics of solar PV tree systems and power management strategies in real applications have been discussed. Challenges involved with the solar PV tree technology have also been addressed as well as suggestions on the direction of further works.

Facile fabrication of ZnO decorated ZnFe-layered double hydroxides @ biochar nanocomposites for synergistic photodegradation of tetracycline under visible light

To explore effective treatment of antibiotics-contaminated water using visible light-responsive photocatalyst, a series of ZnO decorated ZnFe-layered double hydroxide @ biochar (ZnO/ZnFe-LDH@BC) nanocomposites were obtained via a facile hydrothermal method. The fabricated nanocomposites exhibited uniform distribution of ZnO/ZnFe-LDH on BC matrix, allowing more active sites of ZnO/ZnFe-LDH to be utilized. The BC matrix brought widened visible-light absorbance, narrowed bandgap, and improved charge separation and transfer. During photocatalytic degradation of tetracycline (TC) under visible LED light, the nanocomposites showed significant enhancement of degradation efficiency, compared to ZnO/ZnFe-LDH or BC alone, indicating a strong synergy between ZnO/ZnFe-LDH and BC. The nanocomposite containing 23.0 wt% of BC (ZnO/ZnFe-LDH@BC0.2) showed optimal performance (achieving 87.7% of degradation within 4 h) in comparison to the reported LDHs@carbon photocatalysts. Alkaline condition and co-existing CO32– ions could enhance the stability and recyclability of the nanocomposites. Additionally, the possible degradation pathway of TC was analyzed via LC-MS and the reduction in toxicity resulting from photocatalytic degradation was confirmed by the culture of mung bean sprouts. This study provides a rational design strategy and performance assessment of LDH-based nanocomposites for the treatment of antibiotics-contaminated water.