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1. Open markets

   https://doi.org/10.1111/mafi.12294  

   Karatzas, Ioannis; Kim, Donghan (October 2020, Mathematical Finance)

   Abstract An open market is a subset of a larger equity market, composed of a certain fixed number of top‐capitalization stocks. Though the number of stocks in the open market is fixed, their composition changes over time, as each company's rank by market capitalization fluctuates. When one is allowed to invest also in a money market, an open market resembles the entire “closed” equity market in the sense that the market viability (lack of arbitrage) is equivalent to the existence of a numéraire portfolio (which cannot be outperformed). When access to the money market is prohibited, the class of portfolios shrinks significantly in open markets; in such a setting, we discuss the Capital Asset Pricing Model, how to construct functionally generated portfolios, and the concept of universal portfolio. 

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2. Open knots

   https://doi.org/https://doi.org/10.1201/9781138298217  

   Dorier, Julien; Goundaroulis, Dimos; Rawdon, Eric J; Stasiak, Andrzej (January 2021, Encyclopedia of knot theory)

   Adams, Colin; Flapan, Erica; Henrich, Allison; Kauffman, Louis H; Ludwing, Lewis D; Nelson, Sam (Ed.)

   The goal of this chapter is to describe different techniques used to measure knotting in open curves. Note that there is no "agreed upon" definition for describing knotting in open curves. As a result, we describe the context motivating each definition and then describe some advantages and disadvantages of the different approaches. 

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3. Open-ti: open traffic intelligence with augmented language model

   https://doi.org/10.1007/s13042-024-02190-8  

   Da, Longchao; Liou, Kuanru; Chen, Tiejin; Zhou, Xuesong; Luo, Xiangyong; Yang, Yezhou; Wei, Hua (May 2024, International Journal of Machine Learning and Cybernetics)
4. Open Compass: Accelerating the Adoption of AI in Open Research

   https://doi.org/10.1145/3332186.3332253  

   Buitrago, Paola A.; Nystrom, Nicholas A. (October 2019, PEARC '19: Proceedings of the Practice and Experience in Advanced Research Computing on Rise of the Machines (learning))

   Artificial intelligence (AI) has immense potential spanning research and industry. AI applications abound and are expanding rapidly, yet the methods, performance, and understanding of AI are in their infancy. Researchers face vexing issues such as how to improve performance, transferability, reliability, comprehensibility, and how better to train AI models with only limited data. Future progress depends on advances in hardware accelerators, software frameworks, system and architectures, and creating cross-cutting expertise between scientific and AI domains. Open Compass is an exploratory research project to conduct academic pilot studies on an advanced engineering testbed for artificial intelligence, the Compass Lab, culminating in the development and publication of best practices for the benefit of the broad scientific community. Open Compass includes the development of an ontology to describe the complex range of existing and emerging AI hardware technologies and the identification of benchmark problems that represent different challenges in training deep learning models. These benchmarks are then used to execute experiments in alternative advanced hardware solution architectures. Here we present the methodology of Open Compass and some preliminary results on analyzing the effects of different GPU types, memory, and topologies for popular deep learning models applicable to image processing. 

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5. Open capillary siphons

   https://doi.org/10.1017/jfm.2021.1056  

   Wang, Kaizhe; Sanaei, Pejman; Zhang, Jun; Ristroph, Leif (February 2022, Journal of Fluid Mechanics)

   Flow in the inverted U-shaped tube of a conventional siphon can be established and maintained only if the tube is filled and closed, so that air does not enter. We report on siphons that operate entirely open to the atmosphere by exploiting surface tension effects. Such capillary siphoning is demonstrated by paper tissue that bridges two containers and conveys water from the upper to the lower. We introduce a more controlled system consisting of grooves in a wetting solid, formed here by pressing together hook-shaped metallic rods. The dependence of flux on siphon geometry is systematically measured, revealing behaviour different from the conventional siphon. The flux saturates when the height difference between the two container's free surfaces is large; it also has a strong dependence on the climbing height from the source container's free surface to the apex. A one-dimensional theoretical model is developed, taking into account the capillary pressure due to surface tension, pressure loss due to viscous friction, and driving by gravity. Numerical solutions are in good agreement with experiments, and the model suggests hydraulic interpretations for the observed flux dependence on geometrical parameters. The operating principle and characteristics of capillary siphoning revealed here can inform biological phenomena and engineering applications related to directional fluid transport. 

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