•Propose a novel pinball loss guided long short-term memory network.•Design probabilistic forecasting model for individual consumers.•Conduct comprehensive comparisons with the-state-of-the-art ...methods.•Conduct case studies on open dataset and large number of consumers.
The installation of smart meters enables the collection of massive fine-grained electricity consumption data and makes individual consumer level load forecasting possible. Compared to aggregated loads, load forecasting for individual consumers is prone to non-stationary and stochastic features. In this paper, a probabilistic load forecasting method for individual consumers is proposed to handle the variability and uncertainty of future load profiles. Specifically, a deep neural network, long short-term memory (LSTM), is used to model both the long-term and short-term dependencies within the load profiles. Pinball loss, instead of the mean square error (MSE), is used to guide the training of the parameters. In this way, traditional LSTM-based point forecasting is extended to probabilistic forecasting in the form of quantiles. Numerical experiments are conducted on an open dataset from Ireland. Forecasting for both residential and commercial consumers is tested. Results show that the proposed method has superior performance over traditional methods.
This paper aims to conduct a comparative study of the changes in CO2 emission performance of state-owned fossil fuel power plants between China and Korea. For this purpose, we combine the concept of ...the metafrontier Malmquist productivity index and the non-radial directional distance function to develop a new index called the non-radial metafrontier Malmquist CO2 emission performance index (NMMCPI). This new methodology allows for the incorporation of technological heterogeneities and slack variables into the previously introduced Malmquist CO2 emission performance index (MCPI). The NMMCPI can be derived by solving several non-radial data envelopment analysis (DEA) models. The NMMCPI can be decomposed into an efficiency change (EC) index, a best-practice gap change (BPC) index, and a technology gap change (TGC) index. By fixing the non-energy inputs, we measure the pure CO2 emission performance change. Based on the proposed indices, the comparative study between Chinese and Korean fossil fuel power industries is conducted for the 2005–2010 period. Empirical results indicate significant differences in terms of various decomposed CO2 emission performance changes between China and Korea. Korean power plants demonstrate improvements in innovation, while Chinese power plants demonstrate a higher ability for technological leadership. Some related policy implications are also proposed based on the empirical results.
•The non-radial metafrontier Malmquist CO2 emission performance index (NMMCPI) is proposed.•It allows for the incorporation of group heterogeneity and non-radial slack.•The changes in CO2 emission performance and its decomposition of fossil fuel power plants in China and Korea are compared.
The quantum Rabi model, involving a two-level system and a bosonic field mode, is arguably the simplest and most fundamental model describing quantum light-matter interactions. Historically, due to ...the restricted parameter regimes of natural light-matter processes, the richness of this model has been elusive in the lab. Here, we experimentally realize a quantum simulation of the quantum Rabi model in a single trapped ion, where the coupling strength between the simulated light mode and atom can be tuned at will. The versatility of the demonstrated quantum simulator enables us to experimentally explore the quantum Rabi model in detail, including a wide range of otherwise unaccessible phenomena, as those happening in the ultrastrong and deep strong-coupling regimes. In this sense, we are able to adiabatically generate the ground state of the quantum Rabi model in the deep strong-coupling regime, where we are able to detect the nontrivial entanglement between the bosonic field mode and the two-level system. Moreover, we observe the breakdown of the rotating-wave approximation when the coupling strength is increased, and the generation of phonon wave packets that bounce back and forth when the coupling reaches the deep strong-coupling regime. Finally, we also measure the energy spectrum of the quantum Rabi model in the ultrastrong-coupling regime.
A new challenge has arisen in power generation scheduling recently, as the rapid increase in the number of gas-fired units has made power systems more vulnerable to failures in natural gas networks. ...The large-scale integration of wind power further exacerbates the problem because gas-fired units are usually scheduled to catch up wind power uncertainty and thus lead to great variations in the state of gas network. To meet this challenge, it is necessary to commit and dispatch the gas-fired units considering both wind uncertainty and natural gas network security. However, the dynamic characteristics of gas flow are remarkably slower than those of power flow, which should be appropriately modeled to explore its benefits for power system operation. Because directly applying partial differential equations overly complicates the already complicated generation scheduling problem, we address this problem by proposing an approximated transient matrix-form gas flow model. A two-stage robust generation scheduling model is then proposed considering the dynamic security constraints of gas networks and the wind power uncertainty. Moreover, we successfully avoid the nonlinearity of gas flow constraints by developing a new solution methodology. Finally, an illustrative case is presented to demonstrate the effect of gas network dynamics in generation scheduling.
Metal nanoparticles (NPs) stabilized with thiol‐ (HS‐) terminated polymers have applications in medicine, optoelectronics, and catalysis. It is assumed that upon exposure to oxidants or even air, ...these NPs lose colloidal stability, due to the oxidation of the HS‐end‐group and elimination of polymer ligands from the NP surface, however, this mechanism does not explain the unsuccessful recovery of the NP stability by adding fresh HS‐terminated polymers. Here we propose the oxidation of the surface metal atoms as a mechanism for the oxidative elimination of polymer from the NP surface. Based on this mechanism, we reversed NP aggregation by reducing the oxidized metal surface and re‐attaching HS‐terminated polymer ligands. This mechanism is general for various metal NPs and different HS‐terminated polymers. We show that oxidative elimination and reductive addition reactions can improve the colloidal stability of polymer‐capped metal NPs and control their redox stimuli‐responsive self‐assembly.
Oxidative elimination of thiol‐terminated polymers from Au nanoparticle (NP) surfaces occurs due to the oxidation of the surface metal atoms and breakage of Au−Au bonds, and leads to NP aggregation, while reductive addition is used to attach freshly added polymers to the metal surface and restabilize aggregated NPs. This oxidative elimination and reductive addition (OERA) strategy enables improvement of the long‐term NP stability and redox‐responsive self‐assembly of NPs.
By exploiting coordination‐driven self‐assembly, high yields of two 818 molecular metalla‐knots could be obtained using a thiazole‐moiety‐containing asymmetric dipyridyl ligand ...2‐(pyridin‐4‐yl)‐5‐(pyridin‐4‐ylethynyl)benzodthiazole (L1), as confirmed using X‐ray crystallographic analysis, electrospray ionization‐time‐of‐flight/mass spectrometry (ESI‐TOF/MS), and detailed liquid‐state nuclear magnetic resonance (NMR) spectroscopy. To modulate the self‐assembled structures, m‐chloroperbenzoic acid (m‐CPBA) was utilized to oxidize thiazole‐based ligand L1 to N‐thiazole‐oxide‐based ligand 2‐(pyridin‐4‐yl)‐5‐(pyridin‐4‐ylethynyl)benzodthiazole 3‐oxide (L2), which enabled the selective construction of the corresponding tetranuclear macrocycles. Notably, two molecular metalla‐knots could be topologically transformed from 818 knots to simple monocycles because the L1 alkyne bond was inert toward m‐CPBA, as confirmed by liquid‐state NMR spectroscopy, ESI‐TOF/MS, and elemental analysis.
An asymmetric dipyridyl ligand containing a thiazole moiety and two tetracene‐based bimetallic building blocks have been used to synthesize two 818 molecular metalla‐knots in high yields. Post‐synthetic oxidation of the thiazole‐based ligand under mild conditions resulted in the transformation of the 818 molecular metalla‐knots into simple tetranuclear macrocycles.
Production of ethylene glycol from coal is a particularly interesting route as it is an economic alternative to the petrochemical-based route. In this process, effectively generating dimethyl oxalate ...(DMO) is a crucial step by CO oxidative coupling reaction under Pd-based catalysts. However, the aggregation of Pd species over the support is still an issue that relates to the deterioration of catalytic activity and stability. To this end, enhancing the metal–support interaction is urgently required. In this work, hierarchical Nb2O5 (H-Nb2O5) microspheres with abundant oxygen defects were synthesized to anchor the Pd species thus promoting the electron transfer between Pd species and Nb species associated with the generation of interfacial Pd-NbOx sites. Besides, the thinned electron density of Pd species resulting from the electron-withdrawing effect of Nb species is beneficial for activating the adsorbed CO molecules, leading to superior catalytic activity. The Pd/H-Nb2O5 catalyst exhibited 63.1% of CO conversion (theoretical maximum conversion: 64.3%) and 92.9% of DMO selectivity, with a DMO weight time yield of 1297.9 g kgcat.−1 h−1, and remained robust even after 50 h of time on stream evaluation. Current work provides a deep insight into the CO activation mechanism and helps improve the catalytic stability by boosting interfacial electron interaction via oxygen defects induction, and also sheds light on the design and synthesis of high-performance catalysts in other heterogeneous catalysis fields.
The Himalayas and Tibetan Plateau (the HTP), referred to as “the third pole” with an excessive warming rate, exerts strong impacts on the global environment. As one of warming contributors, ...atmospheric brown carbon (BrC) remains limited scientific understanding in the HTP due to a scarcity of observations. In this study, we present a study of the light‐absorbing properties of methanol‐soluble brown carbon (MeS‐BrC) and water‐soluble brown carbon (WS‐BrC) during 2018–2021. Highly spatiotemporal variations of BrC light absorptions were observed. In the HTP marginal area, elevated BrC absorption coefficients at 365 nm (babs,365) and levoglucosan concentrations were obtained, and MeS‐BrC exhibits approximately 1.3–1.8 times higher absorption compared to WS‐BrC. We determined that BrC light absorptions was largely attributed to biomass burning (29%–35%). BrC can act as a potent warming agent in the HTP marginal area, with high direct solar absorption (25%–47% relative to black carbon).
Plain Language Summary
Atmospheric brown carbon (BrC) remains low scientific understanding in the HTP due to a scarcity of observations. Here, we present a plateau‐scale study of the light‐absorbing properties of methanol‐soluble brown carbon (MeS‐BrC) and water‐soluble brown carbon (WS‐BrC) during the period of 2018–2021. This study highlights the contribution of BrC to the HTP warming. Higher BrC light absorption was observed in the HTP marginal area compared with the central HTP. Enhanced radiative absorption effect of WS‐BrC was obtained in the HTP, with an annual average of ∼25% compared with BC in Qinghai Lake and Ngari, and as high as 46.5% in Purang. The results confirmed the importance of BrC from biomass burning in contributing to light‐absorbing aerosols in this region.
Key Points
Brown carbon (BrC) can be a strong warming agent in the marginal Himalayas and Tibetan Plateau
Highly spatiotemporal variations of plateau‐scale BrC were observed
BrC light absorptions was largely attributed to biomass burning
Inaugural Editorial Zhang, Ning
Green and Low-Carbon Economy,
2/2023, Letnik:
1, Številka:
1
Journal Article
Odprti dostop
It gives me great pleasure to write an editorial note for the first edition of the new journal of Green and Low-Carbon Economy (GLCE). A warm welcome to the inaugural issue of GLCE, which is a new ...exciting title for Bon View Press portfolio journals for 2022. GLCE marks a new era for the green and low-carbon development field in approaching carbon neutrality. I am honored and fortunate to be part of GLCE and take responsibility as Editor-in-Chief. As reflected in the journal name, this pioneering journal seeks to understand and address the economic challenges in transitioning to a carbon-neutral world. We encourage authors to conduct multidisciplinary research by applying sound modelling or computational methods and analysis to identify effective and timely solutions for shifting to green and low-carbon economy. Subject areas include, but are not limited to, green and low-carbon economy transition, climate change mitigation and adaption, environmental degradation, renewable energy systems, natural resources management, cost and efficiency, governance, public policy and social behavior, ESG-environmental, social, and corporate governance, green finance, industrial and technological innovations, sustainable production and consumption, and built environment and infrastructure.
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