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Imaging experiments with a 340-GHz FMCW radar and frequency-diverse holograms
No full textWe present recent developments of a standoff imaging system based on a frequency-diverse phase hologram and deep neural networks. The single-pixel imaging system operates in a monostatic configuration consisting of a 340-GHz FMCW radar and a frequency-diverse phase hologram to interrogate the radar down range direction with spatially varying, frequency-dependent field patterns. The measured back-reflected signal contains spatial reflectivity information from the target, and the fast chirp rate of the radar enables real-time imaging performance. Together with simultaneously acquired visible-light images, a deep neural network integrated into the submillimeter-wave data readout electronics can map the received signal onto a 2D image without mechanical or active electrical beam scanning. In experiments, we have collected submillimeter-wave and visible-light data of a moving target in the region of interest with a 60-Hz frame rate. The results suggest that the system can image the moving target with a resolution comparable to the theoretical diffraction limit. The minimal hardware complexity and good imaging performance of the demonstrated computational submillimeter-wave imaging system support its potential as a cost-effective and easily deployable solution for various imaging applications
Evaluating the role of solar photovoltaic and battery storage in supporting electric aviation and vehicle infrastructure at Visby Airport
Get PDFFollowing the societal electrification trend, airports face an inevitable transition of increased electric demand, driven by electric vehicles (EVs) and the potential rise of electric aviation (EA). For aviation, short-haul flights are first in line for fuel exchange to electrified transportation. This work studies the airport of Visby, Sweden and the effect on the electrical power system from EA and EV charging. It uses the measured airport load demand from one year’s operation and simulated EA and EV charging profiles. Solar photovoltaic (PV) and electrical battery energy storage systems (BESS) are modelled to analyse the potential techno-economical gains. The BESS charge and discharge control are modelled in four ways, including a novel multi-objective (MO) dispatch to combine self-consumption (SC) enhancement and peak power shaving. Each model scenario is compared for peak power shaving ability, SC rate and pay-back-period (PBP). The BESS controls are also evaluated for annual degradation and associated cost. The results show that the novel MO dispatch performs well for peak shaving and SC, effectively reducing the BESS’s idle periods. The MO dispatch also results in the battery controls’ lowest PBP(6.9 years) using the nominal economic parameters. Furthermore, a sensitivity analysis for the PBP shows that the peak power tariff significantly influences the PBP for BESS investment
Linear or mixed integer programming in long-term energy systems modeling – A comparative analysis for a local expanding heating system
Get PDFMost computer models used in energy systems optimization modeling studies are formulated usinglinear equations. However, since linear formulations do not always well reflect real-world conditions,they may not always be adequate as policy and support tools. This is particularly the case for localsystem studies attempting to represent technologies at the individual scale, as in the case for localheating system modeling. Thus, the aim of this paper is to investigate differences in the resultingheating solutions and model solution times for a local expanding heating system. Three differentinvestment cost structures for individual and district heating solutions for the heating of new housingare investigated using linear and mixed integer linear programming. The results show that the use ofdistrict heating is higher for the cost structures that use mixed integer linear programming than it isfor the linear cost structures. This result is attributed mainly to the fact that individual air-to-waterheat pumps benefit from the linear equation formulation due to its high coefficient of performanceduring summertime. This finding is important to consider when modeling local energy systems. Thesolution time is, however, significantly shorter for the linear formulations than for the mixed integerlinear formulations
What is the potential value of tokens and token engineering for the architecture, engineering, and construction industry? A positional paper
No full textWhat is the value of tokens for blockchain applications in Architecture, Engineering, and Construction (AEC)? How can token engineering be contextualized in AEC? This positional paper instigates the tackling of these largely unexplored questions. Following a literature review and a visiting of token engineering fundamentals, the paper’s position is that tokens can indeed hold potential value for AEC. This value can be direct, utilitarian, security-related, and/or pegged, and reflected in technical and economic terms. For this value to be realized, the token must be systematically embedded in the AEC ecosystem – therefore dependent on sociotechnical parameters in AEC
Implementation of a coherent real-time noise radar system
Get PDFThe utilisation of continuous random waveforms for radar, that is, noise radar, has been extensively studied as a candidate for low probability of intercept operation. However, compared with the more traditional pulse-Doppler radar, noise radar systems are significantly more complicated to implement, which is likely why few systems exist. If noise radar systems are to see the light of day, system design, implementation, limitations etc., must be investigated. Therefore, the authors examine and detail the implementation of a real-time noise radar system on a field programmable gate array. The system is capable of operating with 100% duty cycle, 200\ua0MHz bandwidth, and 268\ua0ms integration time while processing a range of about 8.5\ua0km. Additionally, the system can perform real-time moving target compensation to reduce cell migration. System performance is primarily limited by the memory bandwidth of the off-chip dynamic random access memory
JANA: Jointly Amortized Neural Approximation of Complex Bayesian Models
No full textThis work proposes “jointly amortized neural approximation” (JANA) of intractable likelihood functions and posterior densities arising in Bayesian surrogate modeling and simulation-based inference. We train three complementary networks in an end-to-end fashion: 1) a summary network to compress individual data points, sets, or time series into informative embedding vectors; 2) a posterior network to learn an amortized approximate posterior; and 3) a likelihood network to learn an amortized approximate likelihood. Their interaction opens a new route to amortized marginal likelihood and posterior predictive estimation - two important ingredients of Bayesian workflows that are often too expensive for standard methods. We benchmark the fidelity of JANA on a variety of simulation models against state-of-the-art Bayesian methods and propose a powerful and interpretable diagnostic for joint calibration. In addition, we investigate the ability of recurrent likelihood networks to emulate complex time series models without resorting to hand-crafted summary statistics
Exploring Logistics-as-a-Service to integrate the consumer into urban freight
Get PDFE-commerce established the consumer as a freight actor. This new reality in the e-commerce supply chain holds economic, social, and environmental opportunities. First, logistics service providers can capitalize on the willingness to pay of consumers with tailored logistics services. Second, consumers can be confronted with the correct costs of delivery options, raising awareness and influencing their choices\u27 sustainability. Third, policymakers can steer the consumer directly, nudging their behaviour to reach urban freight policy objectives. Until now, the lack of interaction between the logistics service provider and the consumer prevented exploiting these opportunities. In this paper, we look at passenger transport, specifically the concept of Mobility-as-a-Service (MaaS), for inspiration on how to integrate the consumer into the logistics market. We propose conceptualizations for a Logistics-as-a-Service (LaaS) platform with different levels of integration and discuss the role of various stakeholders. We conclude with a suite of research questions that deserve attention to develop further the LaaS idea and its proof of concept for consumer logistics
Specifying task allocation in automotive wire harness assembly stations for Human-Robot Collaboration
Get PDFWire harness assembly is normally a manual assembly process that poses\ua0ergonomic\ua0challenges. As a consequence of the rapidly expanding electrification of vehicles and transportation systems, the demand for wire harnesses can be expected to grow radically, further increasing assembly operator challenges. Thus, automating this assembly process is highly prioritised by production engineers. The rapid development of industrial robot technology has enabled more human-robot collaboration possibilities, simplifying the automation of wire harness process tasks. However, successful automation applications involving humans require efficient and safe allocation of tasks between humans and technology. Unfortunately, present assembly system design methods may be obsolete and insufficient in light of the capabilities of emerging automation technologies such as collaborative robots. This paper presents a design and specification methodology for human-centred\ua0manufacturing systems\ua0and focuses on collaborative assembly operations in complex production systems. A case study on human-robot collaboration provides an application example from a wire-harness collaborative assembly process. The proposed design methodology combines\ua0hierarchical task analysis\ua0with assessments of cognitive and physical Levels of Automation (LoAc\ua0and LoAp). The assessments are then followed by evaluations of the Levels of human-robot Collaboration (LoC) and the Levels of operator Skill requirements (LoSr) respectively. A task allocation\ua0matrix supports\ua0the identification of possible combinations of automation and collaboration solutions for a human-centred and collaborative wire harness assembly process. System designers and integrators may utilise the design and specification methodology to identify the potential and extent of human-robot collaboration in collaborative manufacturing assembly operations
From Surviving to Thriving: Industry 5.0 at SMEs Enhancing Production Flexibility
No full textThis study explores how human-centered digitalization can contribute to the flexibility and adaptability of small and medium-sized enterprise (SME) production processes, resulting in more resilient systems. This study explains the relationship between digital technologies and production system features through progressively more human-centric stages of a digitalized manufacturing system. The authors present a case study of an SME that implemented a human-centric strategy, placing people\u27s needs and interests at the center of its processes, leading to more flexible and inclusive production processes and consistent with the goals of Industry 5.0. The results suggest that a digitalized working method that considers human capabilities and needs can enable a more diverse workforce and the rapid setup of new and additional production processes, thus helping SMEs respond to supply chain disruptions. The findings have implications for managers and practitioners interested in driving or supporting the transition of SMEs to human-centric, resilient, and sustainable businesses
Human-centric production and logistics system design and management: transitioning from Industry 4.0 to Industry 5.0
No full textIndustry 4.0 was presented more than a decade ago as the fourth industrial revolution, aiming to significantly raise the level of sophistication of interconnected technologies and thus increase manufacturing industries’ profits. However, because the technology-driven narrow focus of Industry 4.0 on performance and profit fails to explain how to increase prosperity for all the stakeholders involved, the European Commission has introduced the concept of Industry 5.0. This vision overcomes the weaknesses of Industry 4.0 by paying explicit attention to outcomes for humans in the system and establishing an environment to create human-centric, resilient, and sustainable systems. Considering these developments, this position paper and editorial introducing the special issue of the International Journal of Production Research elaborates on the transition from Industry 4.0 to 5.0 through 10 papers focusing on the human-centric pillar of Industry 5.0 and its impacts on production and logistics system design and management. This work presents guidance for a more systemic approach needed in future research: to include empirically grounded works and data-driven multimethod approaches that consider diversity in system operators and human factors demands holistically in order to incorporate ethical implications missing from Industry 4.0–in the pursuit of Industry 5.0 systems