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关键词： Logistics   E-commerce order fulfillment   Order splitting   Warehouse products distribution   Heuristic clustering algorithm  

摘要： In an online supermarket, people may purchase multiple items in a single order for convenience or to obtain free delivery. Multi-item customer orders often need to be split into multiple shipments because the ordered items may be stored in different warehouses. Order splitting results in higher shipping costs. One way to reduce splitting is to store and retrieve all the items in a single warehouse. However, due to the vast volume of items sold by online supermarkets, it is difficult to build and operate such a warehouse. Another way is to optimize the allocation of products in multiple warehouses to reduce order splitting. In this paper, we propose a K-links heuristic clustering algorithm to optimize the product category allocation among multiple warehouses based on the distribution of multi-item orders to minimize the total number of order splits. Using online order and inventory data from a large Chinese online supermarket, we demonstrate that our algorithm performs well and dramatically reduces order splitting. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Differential geometry   Symplectic geometry   Symplectic aspects of mirror symmetry   Homological mirror symmetry   Derived categories   Fukaya category  

关键词： Singularity categories   Noncommutative resolutions   Derived quotients   Recollements   Cohen-Macaulay modules   Isolated hypersurface singularities  

摘要： Given a noncommutative partial resolution A = End(R)(R circle plus M) of a Gorenstein singularity R, we show that the relative singularity category Delta(R) (A) of Kalck-Yang is controlled by a certain connective dga A/(L)AeA, the derived quotient of Braun-Chuang-Lazarev. We think of A/ (L)AeA as a kind of `derived exceptional locus' of the partial resolution A, as we show that it can be thought of as the universal dga fitting into a suitable recollement. This theoretical result has geometric consequences. When R is an isolated hypersurface singularity, it follows that the singularity category Dsg (R) is determined completely by A/(L)AeA, even when A has infinite global dimension. Thus our derived contraction algebra classifies threefold flops, even those X -> Spec(R) where X has only terminal singularities. This gives a solution to the strongest form of the derived Donovan-Wemyss conjecture, which we further show is the best possible classification result in this singular setting. (C) 2021 Elsevier Inc. All rights reserved.

摘要： Human visual cortex contains three scene-selective regions in the lateral, medial and ventral cortex, termed the occipital place area (OPA), medial place area (MPA) and parahippocampal place area (PPA). Using functional magnetic resonance imaging (fMRI), all three regions respond more strongly when viewing visual scenes compared with isolated objects or faces. To determine how these regions are functionally and causally connected, we applied transcranial magnetic stimulation to OPA and measured fMRI responses before and after stimulation, using a theta-burst paradigm (TBS). To test for stimulus category-selectivity, we presented a range of visual categories (scenes, buildings, objects, faces). To test for specificity of any effects to TBS of OPA we employed two control conditions: Sham, with no TBS stimulation, and an active TBS-control with TBS to a proximal face-selective cortical region (occipital face area, or OFA). We predicted that TBS to OPA (but not OFA) would lead to decreased responses to scenes and buildings (but not other categories) in other scene-selective cortical regions. Across both ROI and whole-volume analyses, we observed decreased responses to scenes in PPA as a result of TBS. However, these effects were neither category specific, with decreased responses to all stimulus categories, nor limited to scene-selective regions, with decreases also observed in face-selective fusiform face area (FFA). Furthermore, similar effects were observed with TBS to OFA, thus effects were not specific to the stimulation site in the lateral occipital cortex. Whilst these data are suggestive of a causal, but non-specific relationship between lateral occipital and ventral temporal cortex, we discuss several factors that could have underpinned this result, such as the differences between TBS and online TMS, the role of anatomical distance between stimulated regions and how TMS effects are operationalised. Furthermore, our findings highlight the importance of active co

关键词： subsequent memory effect   Bayesian model selection   episodic memory   parametric fMRI   aging  

摘要： Subsequent memory paradigms allow to identify neural correlates of successful encoding by separating brain responses as a function of memory performance during later retrieval. In functional magnetic resonance imaging (fMRI), the paradigm typically elicits activations of medial temporal lobe, prefrontal and parietal cortical structures in young, healthy participants. This categorical approach is, however, limited by insufficient memory performance in older and particularly memory-impaired individuals. A parametric modulation of encoding-related activations with memory confidence could overcome this limitation. Here, we applied cross-validated Bayesian model selection (cvBMS) for first-level fMRI models to a visual subsequent memory paradigm in young (18-35 years) and older (51-80 years) adults. Nested cvBMS revealed that parametric models, especially with non-linear transformations of memory confidence ratings, outperformed categorical models in explaining the fMRI signal variance during encoding. We thereby provide a framework for improving the modeling of encoding-related activations and for applying subsequent memory paradigms to memory-impaired individuals.

关键词： Noncommutative C*-dynamical systems   Elliott intertwining   Twisted actions   Equivariant Kasparov theory  

摘要： We provide the rigorous foundations for a categorical approach to the classification of C*-dynamics up to cocycle conjugacy. Given a locally compact group G, we consider a category of (twisted) G-C*-algebras, where morphisms between two objects are allowed to be equivariant maps or exterior equivalences, which leads to the concept of so-called cocycle morphisms. An isomorphism in this category is precisely a cocycle conjugacy in the known sense. We show that this category allows sequential inductive limits, and that some known functors on the usual category of G-C*-algebras extend. After observing that this setup allows a natural notion of (approximate) unitary equivalence, the main aim of the paper is to generalize the fundamental intertwining results commonly employed in the Elliott program for classifying C*-algebras. This reduces a given classification problem for C*-dynamics to the prevalence of certain uniqueness and existence theorems, and may provide a useful alternative to the Evans-Kishimoto intertwining argument in future research. (C) 2021 Elsevier Inc. All rights reserved.

关键词： bacterial community   fungal community   high-throughput sequencing   soil properties   wetland degradation  

摘要： Understanding the changes in microbial community composition in wetlands affected by different types of degradation can help enrich theoretical knowledge about wetland degradation. However, studies of the relative role of microorganisms under different types of degradation of wetlands are rare in wetland ecology. Because of agricultural development, a large volume of groundwater has been extracted from the Sanjiang Plain over the last few decades, which has caused wetland degradation. To provide information for the development and protection of this wetland ecosystem, investigations into the processes of wetland degradation are important. The aim of the present work was to assess the impacts of wetland degradation on soil microbial communities under four different types of wetlands degradation in the Sanjiang Plain: swamp meadow (SW), meadow wetland (MW), paddy farmland (PF), and cropland (CL). Both 16S and ITS rRNA gene amplicon sequencing were used to evaluate the diversity and composition of bacteria and fungi. A total of 638,758 effective 16S rRNA and 916,211 valid internal transcribed spacer rRNA gene sequences were obtained, which were classified into 11 fungal and 40 bacterial phyla. The dominant fungal and bacterial phyla were Ascomycota and Proteobacteria, respectively. In addition, wetland degradation increased the relative abundances of Chloroflexi and Gemmatimonadetes, but the relative abundances of Proteobacteria and Verrucomicrobia significantly decreased. The bacterial Shannon index of SW was lower than those of the other investigated sites. Fungal diversity showed no significant differences for different types of degraded wetlands. In addition to wetland degradation, different reactions of the dominant microbial phyla and their diversity were clearly coorelated with total phosphorus (TP), total potassium (TK), available potassium (AK), and soil organic matter (SOM), which formed essential criteria that influenced the soil microbial communities. Wetla

关键词： Common bermudagrass   Root   Transcriptome analysis   WGCNA   Hub genes   Time-specific response  

摘要： Background Despite its good salt-tolerance level, key genes and pathways involved with temporal salt response of common bermudagrass (Cynodon dactylon (L.) Pers.) have not been explored. Therefore, in this study, to understand the underlying regulatory mechanism following the different period of salt exposure, a comprehensive transcriptome analysis of the bermudagrass roots was conducted. Results The transcripts regulated after 1 h, 6 h, or 24 h of hydroponic exposure to 200 mM NaCl in the roots of bermudagrass were investigated. Dataset series analysis revealed 16 distinct temporal salt-responsive expression profiles. Enrichment analysis identified potentially important salt responsive genes belonging to specific categories, such as hormonal metabolism, secondary metabolism, misc., cell wall, transcription factors and genes encoded a series of transporters. Weighted gene co-expression network analysis (WGCNA) revealed that lavenderblush2 and brown4 modules were significantly positively correlated with the proline content and peroxidase activity and hub genes within these two modules were further determined. Besides, after 1 h of salt treatment, genes belonging to categories such as signalling receptor kinase, transcription factors, tetrapyrrole synthesis and lipid metabolism were immediately and exclusively up-enriched compared to the subsequent time points, which indicated fast-acting and immediate physiological responses. Genes involved in secondary metabolite biosynthesis such as simple phenols, glucosinolates, isoflavones and tocopherol biosynthesis were exclusively up-regulated after 24 h of salt treatment, suggesting a slightly slower reaction of metabolic adjustment. Conclusion Here, we revealed salt-responsive genes belonging to categories that were commonly or differentially expressed in short-term salt stress, suggesting possible adaptive salt response mechanisms in roots. Also, the distinctive salt-response pathways and potential salt-tolerant hub genes

关键词： 成语   教学方法   原型范畴理论   文化背景  

摘要： 成语言简意赅,是汉语词汇系统的重要组成部分,在日常生活中无论是口语还是书面语都被广泛的使用,因为有着独特的文化背景,在对外汉语教学中成语也是一个难点,而在成语中动物因为传统语境和审美差异其背后的文化内涵的差异更为显著,这就要求我们要将文化差异引到课堂中,运用有效的教学方法让学生喜欢并理解动物性成语,本文基于认知语言学的原型范畴理论,提出动物性成语的教学方法,以动物原型为点,动物外形、习性、背后文化含义为线,不同的动物性成语的语义为面建立起一个范畴让第二语言学习者在共同文化背景下学习成语,降低学习者的畏难心理.

关键词： Consumer culture positioning   Cross national   Country of origin symbols   International advertising  

摘要： Purpose The present paper explores how advertisers use consumer culture positioning (CCP) strategies in advertising across countries and product categories. Design/methodology/approach The study employs a content analysis approach to investigate usage of CCP strategies and symbols across different CCP strategies, countries and product categories. The authors focussed on country of origin (COO) cues as symbols of CCP. The authors collected printed advertisements from countries at different levels of economic development and communication orientation for the content analysis, namely, Austria (n = 182), Hungary (n = 199) and Turkey (n = 120) and products with high- vs low-involvement levels. Findings Findings of this study indicated that global consumer culture positioning (GCCP) and local consumer culture positioning (LCCP) advertisements relied more on implicit symbols, while foreign consumer culture positioning (FCCP) advertisements predominantly employed explicit ones. Types of symbols and their utilisation varied across countries and product categories, with language, tag lines/logos and brand names being key components across different advertisements. Practical implications The results document the practices of CCP-based advertising, offering important insights on whether and how symbolism can be effectively used for communicating different CCPs across markets. Originality/value Little is known in terms of how specific symbols are used to communicate consumers' culture. In this study, the authors analysed the content of 501 real-print advertisements across multiple countries and product categories. This study contributes to the theory and practice by revealing how consumers' culture manifests through diverse COO symbols in advertising imagery and by facilitating the application of such manifestations across market contexts.