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In recent years, single-frame image super-resolution (SR) has become more realistic by considering the zooming effect and using real-world short- and long-focus image pairs. In this paper, we further investigate the feasibility of applying realistic multi-frame clips to enhance zoom quality via spatio-temporal information coupling. Specifically, we first built a real-world video benchmark, VideoRAW, by a synchronized co-axis optical system. The dataset contains paired short-focus raw and long-focus sRGB videos of different dynamic scenes. Based on VideoRAW, we then presented a Spatio-Temporal Coupling Loss, termed as STCL. The proposed STCL is intended for better utilization of information from paired and adjacent frames to align and fuse features both temporally and spatially at the feature level. The outperformed experimental results obtained in different zoom scenarios demonstrate the superiority of integrating real-world video dataset and STCL into existing SR models for zoom quality enhancement, and reveal that the proposed method can serve as an advanced and viable tool for video zoom., Comment: 11 pages

Reliable information on building rooftops is crucial for utilizing limited urban space effectively. In recent decades, the demand for accurate and up-to-date data on the areas of rooftops on a large-scale is increasing. However, obtaining these data is challenging due to the limited capability of conventional computer vision methods and the high cost of 3D modeling involving aerial photogrammetry. In this study, a geospatial artificial intelligence framework is presented to obtain data for rooftops using high-resolution open-access remote sensing imagery. This framework is used to generate vectorized data for rooftops in 90 cities in China. The data was validated on test samples of 180 km2 across different regions with spatial resolution, overall accuracy, and F1 score of 1 m, 97.95%, and 83.11%, respectively. In addition, the generated rooftop area conforms to the urban morphological characteristics and reflects urbanization level. These results demonstrate that the generated dataset can be used for data support and decision-making that can facilitate sustainable urban development effectively.

Effective simulation methods are becoming critically essential for the analysis of integrated energy systems (IESs) to reveal the interactions of multiple energy carriers. The incorporation of various energy technologies and numerous controllers make the IES a heterogeneous system, which poses new challenges to simulation methods. This paper focuses on the simulation of an IES with hybrid continuous-discrete properties and heterogeneous characteristics. First, a modified third-order quantized state system (MQSS3) method is proposed for the simulation of district heating systems (DHSs), in which quantized state system (QSS) and time-discretized integration are integrated to efficiently manage numerous discrete control actions. Second, an event-driven framework is established to integrate MQSS3 into the simulation of the electricity-heat integrated energy system (EH-IES). This framework enables the adoption of the most suitable models and algorithms for different systems to accommodate the heterogeneous properties of an IES. Case studies of an EH-IES with maximum 80% PV penetration and 210 buildings demonstrate that the dynamic interactions between the DHS and the power distribution network are accurately illustrated by the proposed simulation methods, in which MQSS3 indicates the highest simulation efficiency. It is also demonstrated in the simulation results that the flexibility from DHS can be utilized as demand-side resource to support the operation of power distribution network in aspects such as consuming the surplus PV generations.

Carbon Capture and Storage (CCS) is one of the most potential technologies to mitigate climate change. Usingpipelinesto transport CO2 from emission sources to storage sitesis one of common and mature technologies. The design and operation of pipeline transport process requires careful considerations of thermo-physical properties.This paper studied the impact of properties, including density, viscosity, thermal conductivity and heat capacity, onthe performance of CO2 pipeline transport. The pressure loss and temperature dropin steady state were calculated by using homogenous friction model and Sukhof temperature drop theory, respectively. The results of sensitivity study show thatover-estimating density and viscosity increases the pressure loss while under-estimating of density and viscosity decreases it. Over-estimating density and heat capacity leads to lower temperature drop while under-estimating of density and heat capacity result in higher temperature drop.This study suggests that the accuracy of property models for example, more accurate density model, should be developed for the CO2 transport design.

Solar-assisted post-combustion carbon capture system is studied to compensate the energy penalty of coal-fired plant due to absorbent regeneration. The system is highly integrated with the amine-based carbon capture process coupled with solar thermal sub-system. The dynamic performance is largely affected by the variations of parameters and the fluctuations in solar collectors. Anexperimental facilityof solar-assisted chemical absorptionpilot with two types of collectors (parabolic trough and linear Fresnel) was constructed in this study. The impacts on the absorbent regeneration performance were studied on the dynamic variation of the solar heat and the operating temperature of the reboiler. The results show that an optimum ration of liquid-to-gas of 2.5-3.0 was determined at the lowest of the required regeneration energy. The study suggests thata better understanding of the key parameters associated with both capture process as well as the solar assisted sub-system if of importance for the overall operation and control.

Absorption of CO2 with aqueous amines in post-combustion capture is characterized as mass transfer process with chemical reaction. Hydrodynamics and mass transfer in gas and liquid phases in a packed columnhave significant influences on absorber design especially for the design of packing height. In this paper, the sensitivity study has been conducted to investigate the impacts of gas phase density, viscosity and diffusivity on the hydrodynamics and mass transfer and further the total packing height of a counter-current flow with random packing column, using reactive absorption process and integral rate-based models. Results show that density and diffusivity have opposite effect to viscosity. Amongst various properties, diffusivity has the most significant effect on the packing height compared to density and viscosity. Overestimation of diffusivity of 5% may result in decrease of 3.2% of packing height. Moreover, developing more accurate diffusivity model should be prioritized for more accurate absorber design.

This paper is to describe an open-source code for optimization of clean energy technologies. The model covers the whole chain of energy systems including mainly 6 areas: renewable energies, clean energy conversion technologies, mitigation technologies, intelligent energy uses, energy storage, and sustainability. Originally developed for optimization of renewable water pumping systems for irrigation, the open-source model is written in Matlab® and performs simulation, optimization, and design of hybrid power systems for off-grid and on-grid applications. The model uses genetic algorithm (GA) as optimization technique to find the best mix among power sources, storage systems, and back-up sources to minimize life cycle cost, and renewable power system reliability.

An accurate daylighting simulation can potentially improve the quality of pre-planing buildings and regulating daylighting to achieve the goal of green buildings. However, standard sky models can hardly reproduce real skies in real-time for a specific location within its micro-climate. This paper investigates an embedded photometric device based on high dynamic range (HDR) sky luminance monitoring with high resolution mapping in simulating real-time horizontal work-plane illuminance distribution. To increase time efficiency in the iterative process for the illuminance calculation, a matrix algebraic approach was employed and adapted for the device. The photometric device was validated experimentally in a daylighting test module with external Venetian blinds at different tilt angle of slats. The results indicate the embedded photometric device based on monitored sky can improve accuracy in simulating real-time daylighting provision by over 3 times, with 15%∼37% average error, compared with a common practice using the Perez all-weather model.

This study explored the feasibility of using the Radau pseudospectral method (RPM) to optimize the energy management strategy for a hybrid tracked vehicle. The engine–generator set and the battery pack of the serial hybrid tracked vehicle were modeled and validated through the bench test. A DC-DC converter was equipped between the battery pack and the DC bus in this hybrid powertrain, which increased the flexibility of energy distribution between the engine–generator set and the battery. The optimal control problem was formulated to minimize the fuel consumption through regulating the power distribution properly between the engine–generator set and battery pack during a typical driving schedule. The RPM was applied to transform the optimal control problem to a finite-dimensional constrained nonlinear programming problem. A comparison of the solutions from RPM and dynamic programming showed that the former offers the higher computation efficiency and better fuel economy., Energy Procedia, 88, ISSN:1876-6102, CUE 2015 - Applied Energy Symposium and Summit 2015: Low Carbon Cities and Urban Energy Systems

One of the primary technical challenges of integrating high levels of PV generation into standalone off-grid power supply systems is their variable power output characteristics. In dealing with this issue, the integration of reliable PV forecasting techniques and preferably energy storage, are highly effective. Applying a short-term PV forecasting method, together with a compensatory controllable resource, can help in the management of system operation. This study incorporates the development of an energy flow modelling tool that has been used to analyse the benefits of 1-min ahead PV forecasting and battery storage for different system configurations. Based on the five days of 1-min ahead forecasting results analysed, it is found that PV forecasting enables the prosumer to install more than double the PV capacity, compared to the allowed installed PV capacity when no forecasting is employed. This additional PV capacity saves around 24–25% (on average) of diesel fuel per day for the diesel-PV-battery configuration. The outcomes evidently indicate that incorporating 1-min ahead PV forecasting enables a significant increase of PV hosting capacity of the system, without compromising the reliability of the system.