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Mining research community on the basis of hidden relationships present between its entities is important from academic recommendation point of view. Previous approaches discovered research community by using network connectivity based distance measures (no text semantics) or by using poorer text semantics and relationships of documents DL (Document Level) by ignoring richer text semantics and relationships of VL (Venue Level). In this paper, we address this problem by considering richer text semantics and relationships. We propose a VAT (Venue Author Topic Approach) based on Author-Topic model to discover inherent community structures in a more realistic way by modeling from VL. We show how topics and authors can be inferred for new venues and how author-to-author and venue-to-venue correlations can be discovered. The positive relationship of topic denseness with ranking performance of proposed approach is explained. Experimental results on research collaborative network \"DBLP\" demonstrate that proposed approach significantly outperformed the baseline approach in discovering community structures and relationships in large-scale network.

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The Pratt & Whitney TALON X low emissions combustor: Revolutionary results with evolutionary technology. In 45th AIAA Aerospace Scienc es Meeting and Exhibit (p. 386).", "Park, J., Nguyen, T. H., Joung, D., Huh, K. Y., & Lee, M. C. (2013). Prediction of NO x and CO emissions from an industrial lean - premixed gas turbine combustor using a chemical reactor network model. Energy & Fuels, 27(3), 1 643 - 1651.", "Sahu, A. B., & Ravikrishna, R. V. (2014). A detailed numerical study of NOx kinetics in low calorific value H2/CO syngas flames. International Journal of Hydrogen Energy, 39(30), 17358 - 17370.", "Samuelsen S. Rich burn, quick - mix, lean burn (RQL) com bustor[J]. The Gas Turbine Handbook, US Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory, DOE/NETL2006 - 1230, 2006: 227 - 233.", "Straub, D. L., Casleton, K. H., Lewis, R. E., Sidwell, T. G., Maloney, D. J., & Richards, G. A. (2005). Assessment of rich - burn, quick - mix, lean - burn trapped vortex combustor for stationary gas turbines (No. NETL - TPR - 0629). National Energy Technology Laboratory - In - house Research.", "Zhang, Y., Mathieu, O., Petersen, E. L., Bourque, G., & Curran, H. J. ( 2017). Assessing the predictions of a NOx kinetic mechanism on recent hydrogen and syngas experimental data. Combustion and Flame, 182, 122 - 141."]} This paper presents a kinetics study on NOx emissions of syngas gas turbine with RQL(rich-burn, quick-mix, lean-burn)combustion. The RQL combustor was simulated by a chemical reactor network (CRN) model using CHEMKIN-PRO program. The kinetic mechanism used in the simulation was developed by Zhang et al.(2017),dedicated to syngas fuel. NOx emissions of RQL combustion were systematically studied under representative gas turbine operation conditions, and results show that RQL combustion significantly reduces NOx emissions. Key parameters of RQL combustor, including airflow split and residence time split between rich and lean burn zones, were varied to investigate their effects on NOx emissions. Analyses show that airflow split is the key factor determining NOx formation. Influences of mechanisms on NOx prediction in the RQL combustor were also investigated. The GRI-Mech 3.0mechanismwas chosen for comparison. The syngas mechanism developed by Zhang et al. predicts lower overall NOx emissions when the combustor outlet temperature is 1750K, and predicts higher overall NOx emissions when the outlet temperature is 1908K. In the rich-burn zone of the RQL combustor, the syngas mechanism predicts lowerNOx production at 1750K, and almost the same NOx production at 1908Kcompared with GRI-Mech 3.0. While in the lean-burn zone of the combustor, the syngas mechanism predicts higherNOx formation atboth1750K and 1908K.Sensitivity analyses were conducted to find major reactions that influenced the NOx prediction in each mechanisms. Results show that the dominating pathways of NO formation are not same in each mechanism. ROPs (rates of production) of these pathways were calculated to further explain the differences in predictions of each mechanism.

With the development of modern power systems, especially that of the global energy internet, high-voltage, direct current (HVDC) cable power transmission will play an important role in the future. The key problem of HVDC cable power transmission is the need for novel cable insulation materials that have high performance, recyclability, and higher working temperature to replace traditional crosslinked polyethylene. This paper investigates the thermal and electrical properties of polypropylene (PP)/Al2O3 nanocomposites as a potential recyclable HVDC cable insulation material. The developed nanocomposites exhibit excellent thermal and electrical properties with the introduction of Al2O3 nanoparticles. Particularly, the space charge accumulation is greatly suppressed. Keywords: Global Energy Internet, Power transmission, HVDC cables, Eco-friendly insulation material

Under the Paris Agreement, targets implemented for 2100 specify temperature increases well below 2 °C, with an ambitious target of 1.5 °C. China signed this agreement and will support these global targets. The question remains whether they are possible, especially considering the slow progress in recent decades, despite the fact that the Kyoto Protocol implemented these targets in 2010. The Intergovernmental Panel on Climate Change (IPCC) required modeling research teams to analyze possible pathways, policy options, and cost benefit analyses for GHG mitigation. China’s CO2 emissions from the energy and cement industries already accounted for almost 29% of global emissions in 2017, and this trend is expected to continue increasing. The role of China in global GHG mitigation is therefore crucial. This study presents a scenario analysis for China’s power generation against the background of the global 2 °C and 1.5 °C targets. We discuss the possibility of a lower CO2 emission power generation scenario in China in order to evaluate the national emission pathway towards these targets. Our findings suggest that China can accomplish rapid transition in the power generation sector, reaching its emission peak before 2025. This would make the global 2 °C target possible because energy system development is a key factor. Furthermore, the recent progress of key power generation technologies, potential for further investment in the power generation sector, and recent policy implementation all significantly contribute to China following a low carbon emission development pathway. Keywords: GHG mitigation, Emission scenarios, Global target, China, Modeling

Anthropogenic carbon emissions associated with energy consumption are rapidly increasing. Such carbon emissions are further directly related to global climate change. Thus, reducing carbon emissions to mitigate global climate change has been attracting increasing attention. Energy production and energy consumption is linked by energy networks. The network-constrained energy flow leads to a virtual circulation of embedded carbon emissions. This paper introduces the concept and significance of carbon emission flow (CEF), which helps identify the relationship between carbon emissions and energy consumption. Challenges for extending the CEF from an electricity network to multiple energy systems (MES) are analyzed, and CEF models in both the electricity network and MES are summarized. The distribution of CEF and transfer of carbon emissions are studied using realistic case studies based on the energy interconnection system of Southeast Asia and real-world MES in the Jing-Jin-Ji economic circle. Considering the electricity trade in Southeast Asia in 2050, the results show that significant amounts of carbon emissions are transferred among countries. Approximately 19698 ktCO2 of carbon emissions in Malaysia are attributable to electricity demands of other countries. Conversely, the Philippines and Vietnam would be responsible for additional carbon emissions of 10620 ktCO2 and 42375 ktCO2, respectively. With the CEF model, carbon emissions in different energy sectors can be reasonably quantified, thus facilitating the allocation of emission reduction targets in climate change negotiations and low-carbon policymaking. Keywords: Carbon emission flow, Global climate change, Electricity network, Multiple energy systems

Global climate change is hitherto the most serious environmental problem, and China’s CO2 emissions reductions have been one of the hottest problems discussed in the world. This paper quantifies the impacts of different abatement policies on economy based on a modified MACRO model. The empirical results show that CO2 direct emissions control with the most serious GDP loss is the most effective strategies in term of mitigating CO2 emissions, and carbon tax on coal with great effects and less economic loss is the most suitable strategy for China.

An important topic in Monte Carlo neutron transport calculations is to verify that the statistics of the calculated estimates are correct. Undersampling, non-converged fission source distribution and inter-cycle correlations may result in inaccurate results. In this paper, we study the effect of the number of neutron histories on the distributions of homogenized group constants and assembly discontinuity factors generated using Serpent 2 Monte Carlo code. We apply two normality tests and a so-called "drift-in-mean" test to the batch-wise distributions of selected parameters generated for two assembly types taken from the MIT BEAVRS benchmark. The results imply that in the tested cases the batch-wise estimates of the studied group constants can be regarded as normally distributed. We also show that undersampling is an issue with the calculated assembly discontinuity factors when the number of neutron histories is small.