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961.
Dr. Mohammad Alipour Prof. Shiva Sander Tavallaey Dr. Anna M. Andersson Prof. Daniel Brandell 《Chemphyschem》2022,23(7):e202100829
The ability to accurately predict lithium-ion battery life-time already at an early stage of battery usage is critical for ensuring safe operation, accelerating technology development, and enabling battery second-life applications. Many models are unable to effectively predict battery life-time at early cycles due to the complex and nonlinear degrading behavior of lithium-ion batteries. In this study, two hybrid data-driven models, incorporating a traditional linear support vector regression (LSVR) and a Gaussian process regression (GPR), were developed to estimate battery life-time at an early stage, before more severe capacity fading, utilizing a data set of 124 battery cells with lifetimes ranging from 150 to 2300 cycles. Two type of hybrid models, here denoted as A and B, were proposed. For each of the models, we achieved 1.1 % (A) and 1.4 % (B) training error, and similarly, 8.3 % (A) and 8.2 % (B) test error. The two key advantages are that the error percentage is kept below 10 % and that very low error values for the training and test sets were observed when utilizing data from only the first 100 cycles.The proposed method thus appears highly promising for predicting battery life during early cycles. 相似文献
962.
Gold nanoparticles supported on thiol‐functionalized reduced graphene oxide as effective recyclable catalyst for synthesis of tetrahydro‐4H‐chromenes in aqueous media 下载免费PDF全文
Gold nanoparticles supported on thiol‐functionalized reduced graphene oxide (AuNPs@RGO‐SH) were found to be a biocompatible, stable, recyclable heterogeneous catalyst. The catalysts were characterized by field emission scanning electron microscopy (FE‐SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT‐IR), thermal gravimetric analysis (TGA), and X‐ray diffraction spectroscopy (XRD). The obtained catalyst was used in synthesis of tetrahydro‐4H‐chromenes in aqueous media with excellent yields. The catalysts could be easily separated from the reaction mixture and recovered several times without a significant loss of activity. 相似文献
963.
Ke Chen Shaofeng Deng Yun Lu Mingxing Gong Yezhou Hu Tonghui Zhao Tao Shen Deli Wang 《中国化学快报》2021,32(2):765-769
The Platinum(Pt)-based catalysts exhibit excellent catalytic performance for the hydrogen evolution reaction(HER) while suffering from poor stability due to the weak interaction between the carbon support and Pt.Herein,a molybdenum-doped titanium dioxide(Ti_(0.9)Mo_(0.1)O_2) supported low-Pt electrocatalyst with stronger interaction between catalyst and support is applied to tune the electrocatalytic performance of Pt.The Ti_(0.9)Mo_(0.1)O_2 support can not only tolerate the corrosion environment in the catalytic system,but also generate strong metal-support inte raction(SMSI) between the oxide and catalyst.A facile solvothermal method is used to prepare Ti_(0.9)Mo_(0.1)O_2 as support to anchor Pt nanoparticles.The 5% Pt supported on Ti_(0.9)Mo_(0.1)O_2 catalyst exhibits 4.4-fold mass activity(MA) at an overpotential of 50 mV and higher stability than 20% Pt/C with only 1/4 Pt loading.The SMSI between the Ti_(0.9)Mo_(0.1)O_2 and Pt prevents the Pt aggregation to achieve excellent stability,and hydrogen spillover effect in the interface between Pt and support benefits the hydrogen production process.This work presents a novel sight for the fabrication and design of oxide supported catalysts in various catalytic system by reasonably employing support effect. 相似文献
964.
This paper develops a risked-based premium calculation model for the insurance provided by the Pension Benefit Guaranty Corporation (PBGC). It takes account of the pension fund’s and the plan sponsor’s investment policy and extends Chen (2011) by considering distress termination triggered by the sponsor’s underfunding. We empirically illustrate our theoretical pricing formula for the 100 biggest American DB sponsoring companies. Our result clearly casts doubt on the current practice where about 70% of the PBGC premiums charged are flat. We observe that the funding ratio and the leverage are the main risk factors in a risk-based premium calculation. 相似文献
965.
Scientific Research Assessment (SRA) is receiving increasing attention in both academic and industry. More and more organizations are recognizing the importance of SRA for the optimal use of scarce resources. In this paper, a vague set theory based decision support approach is proposed for SRA. Specifically, a family of parameterized S-OWA operator is developed for the aggregation of vague assessments. The proposed approach is introduced to evaluate the research funding programs of the National Natural Science Foundation of China (NSFC). It provides a soft and expansive way to help the decision maker in NSFC to make his decisions. The proposed approach can also be used for some other agencies to make similar assessment. 相似文献
966.
In spite of the importance of warehousing to the customer service and cost levels of many businesses, there is currently not a comprehensive systematic method for designing warehouses. In this paper, the current literature on the overall methodology of warehouse design is explored, together with the literature on tools and techniques used for specific areas of analysis. The general results from the literature have then been validated and refined with reference to warehouse design companies. The output is a general framework of steps, with specific tools and techniques that can be used for each step. This is intended to be of value to practitioners and to assist further research into the development of a more comprehensive methodology for warehouse design. 相似文献
967.
Marzena Białek Anna Pietruszka 《Journal of polymer science. Part A, Polymer chemistry》2009,47(14):3480-3489
Ethylenebis(5‐chlorosalicylideneiminato)vanadium dichloride supported on MgCl2(THF)2 or on the same carrier modified by EtnAlCl3?n, where n = 1–3, was used in ethylene polymerization in the presence of MAO or a common alkylaluminium compounds as a cocatalyst. The support type alter vanadium loading and also change the characteristic of the catalytic active sites. Et2AlCl is the best activator for a catalyst which has been immobilized on a nonmodified support, whereas the systems which contain a carrier which has been modified by an organoaluminium compound reveal the highest activity in conjunction with MAO. That difference, together with different temperature effects on polymerization efficiency (i.e., decrease and increase of catalytic activity for increasing temperatures, respectively) suggest the formation of different types of active sites in the catalytic systems supported on modified and nonmodified magnesium carrier. However, all supported precatalysts possess a long lifetime, still being active towards ethylene polymerization after 2 h. All the systems yield wide MWD polyethylene, while bimodal MWD is found for some part of analyzed samples. Polyethylene with bimodal particle size distribution is formed with the system which contain modified carriers at higher temperatures. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3480–3489, 2009 相似文献
968.
We have developed an internet-based management game to illustrate the economic and organisational decision-making process in a hospital by using discrete event simulation. Up to six hospitals compete against each other for inpatients with different disease categories and budget depending on hospital mission, regional health policy, inpatient reimbursement system (day-, case- and global-budget based) as well as labour and radiology technology market for 12 decision periods. Players can evaluate alternative actions for capacity planning as well as patient scheduling and control problems depending on different game situations. The uniqueness of COREmain hospital game consists of the internet-based framework, the combination of resource, process and financial result management, the competition of hospitals within a region and the consideration of different inpatient reimbursement systems. The deployment of this game in teaching, policy and research might improve policy making both at a hospital, regional and national level and also induce further research in these fields. 相似文献
969.
Participatory budgets are becoming increasingly popular in many municipalities all around the world. The underlying idea is to allow citizens to participate in the allocation of a municipal budget. Many advantages have been suggested for such experiences, including legitimization and more informed and transparent decisions. There are many conceivable variants of such processes. However, in most cases both its design and implementation are carried out in an informal way. In this paper we propose a methodology to design a participatory budget process based on a multicriteria decision making model. 相似文献
970.
V. Yu. Voronov 《Moscow University Computational Mathematics and Cybernetics》2009,33(2):101-108
A technique for the automatic selection of the method for solution of a sparse system of linear algebraic equations (SLE) and selection of the method parameters from the analysis of the SLE matrix of coefficients is presented. The parameters are selected so as to maximize the performance metric. A formal model of the performance of a SLE solver is presented and is used to formulate an algorithm for construction, precedent learning, and application of the proposed method. The method is approved for iterative SLE solvers from the PETSc parallel library of the MVS-100K supercomputer platform at the Interdepartmental Supercomputer Center of the Russian Academy of Sciences. 相似文献