From the 100-day TESS observations, we comprehensively studied the variations of the light curve and orbital period for EE Cet. It is found that an 83.2-day oscillation occurs in the differences ...between two light maxima, which identifies the existence of chromospheric activity. Using the 2016-version Wilson–Devinney code, we obtained three sets of photometric solutions from TIC1432, TIC2449 and TIC2495. Results imply a dark spot immigrating from longitude 217.9(±2.2)∘ in BJD 2459449 into longitude 61.6(±0.7)∘ in BJD 2459495. From the eclipse timing residuals (i.e., observed minus computed), the orbital period of EE Cet may be undergoing a long-term period increase with a periodic variation. The 15.95-yr periodic oscillation with A=0.0038(1) d may result from the light-time effect due to the third body. Meanwhile, the orbital period increases at a rate of dP/dt=1.74(±0.02)×10−7dyr−1, which may result from the conserved mass transfer from the less massive component to the more massive one. With mass transferring, EE Cet will evolve into the broken-contact configuration, as predicted by the TRO theory.
•We analyzed TESS Light-curves for EE Cet and discovered an 83.2-day oscillation occuring in the difference between the two light maxima.•From the photometric solutions, the spot immigrates and disappears on the surface of the more massive component, which identifies the existence of chromospheric activity.•The orbital period is increasing continuously, accompanied by a light-time effect with a period of 15.95 years due to the third body. With the mass transferring, EE Cet will evolve into a broken-contact configuration.
The National Test Commission, belonging to the Spanish Psychological Association, prepares an annual review of the tests published in Spain. In this edition, the Commission, different publishing ...houses (TEA Hogrefe, Pearson Education, GiuntiEOS, and CEPE), and twelve external evaluators (six specialists in the substantive subject and six experts in sychometrics) have been involved. The review carried out is based on the European model of evaluation of the quality of the tests adapted to Spanish, which has resulted in the Revised Test Evaluation Questionnaire (CET-R). As a general result, it should be noted that the quality of the six uestionnaires evaluated is good and consistent with the results obtained in previous reviews. Furthermore, different aspects of improvement in the evaluation process are presented
In order to fulfill the goals of sustainable development and emission reduction, as the main contributor to emissions, optimizing the electric structure is imperative for Chinese electric power ...industry. In the "thirteenth five-year" period, China has implemented tradable green certificates (TGC) and carbon emissions trading (CET) in the electricity market to accelerate the development of renewable energy. In this study, we analyze and simulate the dual effects of TGC and CET on the electricity market based on the theories and models of equilibrium and system dynamics. The obtained results show that: (1) The increase of renewable portfolio standards and carbon price is advantageous to the expansion of green electricity. The higher the portfolio standard and the carbon price are, the better the electric structure optimization could be. (2) The proportion of renewable energy power generation is expected to achieve the goal of ‘renewable energy thirteenth five-year development planning’ by 2020 (Goal: 680 million kW, 1.9 trillion kW h, 27% of all electricity generated). (3) The CO2 emission in the electric power industry will be controlled, meanwhile effectively promoting the realization of national CO2 emission-reduction target by 2020 (Target: below 1.6298 ton CO2 emission/10,000 yuan). (4) TGC system and CET system are incentive compatible in China. Finally, we propose some policy recommendations on the mechanism design and implementation for these two systems.
•Build equilibrium models of TGC market, CET market and electricity market.•Analyze the interaction of TGC price, carbon price and electricity price.•Construct a coupling SD model of TGC market, CET market and electricity market.•Simulate the dual effects of TGC and CET on the electricity market.•Propose policy recommendations on the parallel implementation of TGC and CET in China.
This article presents a distributed alternating direction method of multipliers (ADMMs) approach for solving the direct current dynamic optimal power flow with carbon emission trading (dc-DOPF-CET) ...problem. Generally, the ADMM-based distributed approaches disclose boundary buses and branches information among adjacent subsystems. As opposed to these methods, the proposed method (dc-ADMM-P) adopts a novel strategy which uses consensus ADMM to solve the dual of dc-DOPF-CET while only discloses boundary branches information among adjacent subsystems. Moreover, the convergence performance of dc-ADMM-P is improved by reducing the number of dual multipliers and employing an improved update step of the multiplier. DC-ADMM-P is tested on cases ranging from 6 to 1062 buses, with comparison with other distributed/decentralized methods. The simulation results verify the high efficiency of dc-ADMM-P in solving the dc-DOPF problem with complex (nonlinear) factors which can be formulated as convex separable functions. Meanwhile, it also shows the improvement of convergence performance by reducing the number of dual multipliers and employing a new update strategy for the multiplier.
The Arabian-Nubian Shield (ANS) underwent a regional carbonation event with CO2 fluxes derived from the mantle and circulated along post-accretionary shear zones, thus affecting the redistribution of ...gold mineralization. Formerly, the analyses of remotely-sensed data have suggested regions of gold mineralization linked to the post-accretionary structured framework, but the results were insufficient for detailed prospecting in the ANS. In this research, aeromagnetic data and Landsat-8 imagery were integrated for delineating new high potential zones of gold mineralization in the Allaqi-Heiani Suture (AHS) zone, the ANS, South Eastern Desert (SED) of Egypt. Aeromagnetic data were enhanced using the Center for exploration targeting (CET) grid enhancement technique to detect the main structures that control hydrothermal alterations in the study area. Principal Component Analysis (PCA) technique and ratios of spectral bands were applied to Landsat-8 data for mapping zones of hydrothermal alteration associated with gold mineralization. The traced structural elements from RTP, CET and Landsat-8 maps were statistically plotted and interpreted using rose diagrams. These diagrams indicated that the NW and NE trends are the most dominant in the RTP map and that the intersection zones obtained from the CET analysis are aligned along the NW-oriented trend. While the NNW, WNW and NE trends were the most dominant ones in Landsat maps. The integration of the results indicates several new high potential zones of gold and Cu/Ni mineralization types, which are mostly concentrated at the western part of the AHS zone. The hydrothermal alteration zones and associated gold mineralization are strongly linked to NW, NE, E-W and WNW trending lineaments. The approach used in this study can be applied to other parts of the ANS and other regions with similar geological conditions around the world.
For a successful repair of single-crystal (SX) components, an epitaxial growth of columnar dendrites is required, i.e. a columnar to equiaxed transition (CET) has to be avoided. In this study it was ...found that changing the angles of laser treatment with respect to the standard orientation 100(001) can have a strong and positive effect on the quality of the part. By rotating the SX substrate around x-, y-, and z-axis, which coincide with the 100, 010, and 001 crystallographic directions, respectively, the effect of the substrate orientation for different rotation angles on the columnar-to-equiaxed transition (CET) in laser remelting process was determined. It was found that from the 100 (001) initial state, the CET varies strongly with the substrate orientation when the rotation is made around the y-axis, whereas there is nearly no change when the rotation is performed around the x- or z-axis. This drastic difference is caused by the fact that for rotation around the y-axis by 45° the melt pool contains no intersection point where dendrite domains with three preferred 〈100〉 growth directions meet. For the rotation about the x or z-axis, at least one intersection point appears. The intersection point is the most vulnerable place for the CET since the thermal gradient tends to reach its minimal value there. The number and location of the intersection points jointly control the overall CET tendency. Reducing those points and/or moving them to the positions with high thermal gradient are beneficial for avoiding CET generally. Our results clearly demonstrate that the laser processing window for the repair of the single crystal superalloy can be enlarged if the substrate orientation is rotated correspondingly.
With the development of smart grid, demand-side resources (DSR) will play an increasingly important role in the power balance of supply and demand. In addition, the requirement of a low-carbon smart ...grid means some policy backgrounds, such as carbon emissions trading (CET), should not be ignored. Under these circumstances, it is a good idea to construct a novel unit commitment (UC) model. This paper proposes a model that not only takes advantage of various resources on the demand side, such as electric vehicles, demand response, and distributed generation, but also reflects the effects of CET on generation schedule. Then, an improved particle swarm optimization (IPSO) algorithm is applied to solve the problem. In numerical studies, we analyze the impacts of DSR and CET on the results of UC, respectively. In addition, two meaningful experiments are conducted to study the approaches to allocate emission quotas and the effects of price transmission mechanism.
As a flexible market mechanism based on the control of total quantity, the carbon emission trading system aims to achieve economic development while reducing carbon emissions and energy consumption. ...How to improve the effectiveness of carbon emission trading (CET) policy and achieve the established emission reduction targets have attracted widespread attention from scholars. Taking Guangdong Province as an example, this paper constructed a system dynamics (SD) model to investigate the interaction between internal factors of CET system and simulated the effectiveness of CET policy from 2016-2026. The results indicate that (1) Relative errors between historical data and simulated data are controlled within 5%, which indicates that the system model is suitable to simulate real system. (2) The average sensitivity of the quota variation rate, paid ratio and penalty coefficient are 0.42, 0.56 and 0.29, respectively, indicating that these three parameters can be identified as leverage parameters affecting the efficiency of the CET policy. (3) A single type of policy is difficult to achieve emission reduction targets. The policy portfolio scenario will achieve the reduction target in Thirteenth Five-Year plan of Guangdong, that is, the total amount of quota decreases by 0.5% per year, the paid ratio rises 2% in that ratio per year, and the penalty coefficient is triple the carbon price.
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The columnar-to-equiaxed transition (CET) or the formation of stray grains in the laser melting deposition is the least desirable for the repair of single-crystal blades. In this ...work, the forced water-cooling was conducted on a single-crystal René N5 substrate during the direct energy deposition (DED). The single track remelting, one-layer, two-layer, and eight-layer depositions were investigated to explore the grain growth mechanism. The solidification conditions of the DED process, including temperature field, temperature gradient, and solidification speed, were numerically analyzed by a finite element model. The single-track remelting results showed that the fraction of columnar crystal regions increases from 55.81 % in the air-cooled sample to 77.14 % in the water-cooled one. The single-track deposits of one- and two-layer have the same trend, where the proportion of columnar crystal height was higher under the forced water-cooled condition. The electron backscattered diffraction (EBSD) grain-structure maps of an eight-layer deposit show that the epitaxial growth height increases from 1 mm in the air-cooling sample to 1.5 mm in the water-cooling one. The numerical results showed that the temperature gradient in 001 direction was significantly increased by using forced water-cooling. In conclusion, the in-situ substrate cooling can become a potential method to promote epitaxial growth during DED via the influence on CET occurrence.
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