This paper constructs a unique dataset of Chinese firm-level bilateral cross-border e-commerce exports using the back-end online logistics database of a famous Chinese logistics platform to study the impact of destina...
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This paper constructs a unique dataset of Chinese firm-level bilateral cross-border e-commerce exports using the back-end online logistics database of a famous Chinese logistics platform to study the impact of destination country's institutional quality on Chinese cross-border e-commerce export. Our results show that the institutional quality of destination countries significantly boosts China's cross-border e-commerce exports. Institutional quality has a more significant effect on the extensive margin than the intensive margin. Mechanism analysis shows that institutional quality significantly stimulates export entry, export survival, and continuous exports. furthermore, destination country's institutional quality has a greater impact on cross-border e-commerce export than on traditional export.
In this work, we solve time, space and time-space fractional Schrodinger equations based on the non-singular Caputo-fabrizio derivative definition for 1D infinite-potential well problem. To achieve this, we first work...
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In this work, we solve time, space and time-space fractional Schrodinger equations based on the non-singular Caputo-fabrizio derivative definition for 1D infinite-potential well problem. To achieve this, we first work out the fractional differential equations defined in terms of Caputo-fabrizio derivative. Then, the eigenvalues and the eigenfunctions of the three kinds offractional Schrodinger equations are deduced. In contrast to Laskin's results which are based on Riesz derivative, both the obtained wave number and wave function are different from the standard ones. Moreover, the number of solutions is finite and dependent on the space derivative order. When the fractional orders of derivatives become integer numbers (one for time derivative or/and two for space), our findings collapse to the standard results.
Predicting defects during software testing reduces an enormous amount of testing effort and help to deliver a high-quality software system. Owing to the skewed distribution of public datasets, software defect predicti...
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Predicting defects during software testing reduces an enormous amount of testing effort and help to deliver a high-quality software system. Owing to the skewed distribution of public datasets, software defect prediction (SDP) suffers from the class imbalance problem, which leads to unsatisfactory results. Overfitting is also one of the biggest challenges for SDP. In this study, the authors performed an empirical study of these two problems and investigated their probable solution. They have conducted 4840 experiments over five different classifiers using eight NASA projects and 14 PROMISE repository datasets. They suggested and investigated the varying kernel function of an extreme learning machine (ELM) along with kernel principal component analysis (K-PCA) and found better results compared with other classical SDP models. They used the synthetic minority oversampling technique as a sampling method to address class imbalance problems and k-fold cross-validation to avoid the overfitting problem. They found ELM-based SDP has a high receiver operating characteristic curve over 11 out of 22 datasets. The proposed model has higher precision and f-score values over ten and nine, respectively, compared with other state-of-the-art models. The Mathews correlation coefficient (MCC) of 17 datasets of the proposed model surpasses other classical models' MCC.
This paper draws on the author's work in social epistemology and on comparative studies of sciences of human behavior to draw attention to the importance of interaction. Drawing further on recent and contemporary ...
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This paper draws on the author's work in social epistemology and on comparative studies of sciences of human behavior to draw attention to the importance of interaction. Drawing further on recent and contemporary research in biology, she argues that interaction ought to be considered a distinct ontological category, not reducible to properties of its participants.
We describe the case of a 75-year-old patient who progressed over a 12-year period from localized to symptomatic metastatic prostate cancer (PrCa) with lung as the sole organ of involvement. In this case, the specific...
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We describe the case of a 75-year-old patient who progressed over a 12-year period from localized to symptomatic metastatic prostate cancer (PrCa) with lung as the sole organ of involvement. In this case, the specific sequence of positron emission tomography (PET)-based next-generation imaging with
A kind of Y-bearing ferritic/martensitic fuel cladding tube with qualified dimensions, acceptable mechanical properties as well as good flattening and flaring performance was manufactured recently by our group. In thi...
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A kind of Y-bearing ferritic/martensitic fuel cladding tube with qualified dimensions, acceptable mechanical properties as well as good flattening and flaring performance was manufactured recently by our group. In this paper, to improve and further evaluate its oxidation resistance, the cladding tube was aluminized firstly and then subjected to high temperature steam oxidation at 1200 degrees C for 8 h. The results indicated that aluminizing coating with gradient content of Al was prepared on the tube successfully. And the matrix microstructure was transformed from tempered martensite into ferrite during aluminizing. Weight gains after high temperature steam oxidation were 72.7 and 1.48 mg cm(-2)for the bare and aluminized tubes, respectively. The latter one exhibited better oxidation resistance due to the generated dense aluminum oxide film. Meanwhile, Kirkendall pores were formed near oxidation surface and should be eliminated for the real application of the aluminized tube in the future.
A graphGis called a fractional (g, f)-covered graph iffor anye is an element of E(G),Gadmits a fractional (g, f)-factor coveringe. A graphGis called a fractional (g, f, n)-critical covered graph iffor anyS subset of...
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A graphGis called a fractional (g, f)-covered graph iffor anye is an element of E(G),Gadmits a fractional (g, f)-factor coveringe. A graphGis called a fractional (g, f, n)-critical covered graph iffor anyS subset of V(G) with divide S divide = n,G - Sis a fractional (g, f)-covered graph. A fractional (g, f, n)-critical covered graph is said to be a fractional (a, b, n)-critical covered graph ifg(x) = aandf(x) = bfor everyx is an element of V(G). A fractional (a, b, n)-critical covered graph was first defined and studied in [1]. In this article, we investigate fractional (g, f, n)-critical covered graphs and present a binding number condition for the existence offractional (g, f, n)-critical covered graphs, which is an improvement and generalization of a previous result obtained in [2].
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