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排序方式: 共有197条查询结果,搜索用时 15 毫秒
31.
The National Collegiate Athletic Association (NCAA) organizes a men's basketball tournament every March to determine the national champion for the current season. In organizing the tournament, the emphasis is typically on selection of the most deserving teams to participate and providing a fair, equitable environment in which to play that result in a true, undisputed champion for the season. However, there are growing concerns of dwindling actual attendance at tournament games and increasing financial burden on the NCAA related to reimbursable team travel expenses. In this paper, we describe the development of an integer program designed to optimize team assignments in the sense of minimizing the distance travelled by teams to game sites and the corresponding travel costs. The goal is to increase tournament accessibility to fans as well as lessen the financial impact to the NCAA while maintaining the integrity of the tournament. We test our model against actual tournament assignments from the past 5 years. Results show consistent and significant cost savings and reductions in distance travelled without compromising the fairness and structure of the tournament. Overall, we demonstrate the usefulness of the model in both operational and strategic business decisions. 相似文献
32.
In this paper, we introduce conformable variational iteration method (C-VIM), conformable fractional reduced differential transform method (CFRDTM) and conformable homotopy analysis method (C-HAM). Between these methods, the C-VIM is introduced for the first time for fractional partial differential equations (FPDEs). These methods are new versions of well-known VIM, RDTM and HAM. In addition, above-mentioned techniques are based on new defined conformable fractional derivative to solve linear and non-linear conformable FPDEs. Firstly, we present some basic definitions and general algorithm for proposal methods to solve linear and non-linear FPDEs. Secondly, to understand better, the presented new methods are supported by some examples. Finally, the obtained results are illustrated by the aid of graphics and the tables. The applications show that these new techniques C-VIM, CFRDTM and C-HAM are extremely reliable and highly accurate and it provides a significant improvement in solving linear and non-linear FPDEs. 相似文献
33.
Kök M. V. Pokol G. Keskin C. Madarász J. Bagci S. 《Journal of Thermal Analysis and Calorimetry》2004,75(3):781-789
In this study the combustion characteristics of crude oils (Karakuę and Beykan) in the presence of a limestone matrix were
determined using the thermogravimetry (TG/DTG). Experiments were performed at a heating rate of 10°C min-1, whereas the air flow rate was kept constant at 10 L h-1 in the temperature range of 20-900°C. In combustion with air, three distinct reaction regions were identified in all crude
oil/limestone mixtures studied known as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation
(HTO). The individual activation energies for each reaction region may be attributed to different reaction mechanisms, but
they do not give any indication of the contribution of each region to the overall reactivity of the crude oils. Depending
on the characteristics, the mean activation energy of samples varied between 50.3 and 55.8 kJ mol-1.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
34.
Baki Ünal 《Entropy (Basel, Switzerland)》2022,24(8)
In this study, causalities of COVID-19 across a group of seventy countries are analyzed with effective transfer entropy. To reveal the causalities, a weighted directed network is constructed. In this network, the weights of the links reveal the strength of the causality which is obtained by calculating effective transfer entropies. Transfer entropy has some advantages over other causality evaluation methods. Firstly, transfer entropy can quantify the strength of the causality and secondly it can detect nonlinear causal relationships. After the construction of the causality network, it is analyzed with well-known network analysis methods such as eigenvector centrality, PageRank, and community detection. Eigenvector centrality and PageRank metrics reveal the importance and the centrality of each node country in the network. In community detection, node countries in the network are divided into groups such that countries in each group are much more densely connected. 相似文献
35.
36.
We allow the reference point in (cooperative) bargaining problems with a reference point to be endogenously determined. Two loss averse agents simultaneously and strategically choose their reference points, taking into consideration that with a certain probability they will not be able to reach an agreement and will receive their disagreement point outcomes, whereas with the remaining probability an arbitrator will distribute the resource by using (an extended) Gupta–Livne bargaining solution (Gupta and Livne in Manag Sci 34:1303–1314, 1988). The model delivers intuitive equilibrium comparative statics on the breakdown probability, the loss aversion coefficients, and the disagreement point outcomes. 相似文献
37.
Circumstances under which a quenched system will freeze in a metastable state are studied in simple systems with long-range order. The model used is the time-dependent pair approximation, based on the most probable path (MPP) method. The time dependence of the solution is shown by means of flow diagrams. The fixed points and other features of the differential equations in time are independent of the choice of the rate constants. It is explained qualitatively how the system behaves under varying descending temperatures: the role of the initial conditions, the dependence on the quenching rate, and the response to precooling. 相似文献
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39.
Kaya Irfan Özdemir Yalçın Kaya Eren Keskin Mehmet Emin 《Journal of Thermal Analysis and Calorimetry》2020,139(2):817-822
Journal of Thermal Analysis and Calorimetry - In this study, the effects of heating and cooling rate on the thermal properties of high nickel-rich Ni55Ti45 shape memory alloy were investigated.... 相似文献
40.
Fatma Aytan Kiliçarslan Bahadir Keskin İbrahim Erden 《Journal of Coordination Chemistry》2017,70(15):2671-2683
The chemical synthesis and characterization with spectroscopic and electrochemical properties of [bis(4-fluorophenyl)-methoxy]-substituted metallo-phthalocyanines were reported for the first time. The new phthalocyanines have been characterized by elemental analysis, UV-Vis, FT-IR, and mass spectroscopies. The aggregation behavior of the phthalocyanine compounds was investigated in different solvents and concentrations. It is found that the fluoro substituents of peripherally Co and Cu complexes are examined and induce a shift to the redox processes toward the negative potentials and formed more reversible processes. Metal-based reduction and oxidation reactions were obtained for the Co(II) complex, whereas Cu(II) complexes exhibited Pc-ring-based electron-transfer reactions. The voltammetric measurements supported the proposed structure of the complexes. 相似文献