57 research outputs found
Author Correction:DNA methylation predicts age and provides insight into exceptional longevity of bats
No full textCorrection to: Nature Communications https://doi.org/10.1038/s41467-021-21900-2, published online 12 March 2021.The original version of this Article omitted from the author list the 34th author L. Gerardo Herrera M., who is from the ‘Estación de Biología de Chamela, Instituto de Biología, Universidad Nacional Autónoma de México, 48980 San Patricio, Mexico’ and the 35th author José J. Flores-Martínez, who is from the ‘Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico’. Additionally, the following was added to the Author Contributions: ‘L.G.H.M., J.J.F.M., M.N., B.P., M.L.P., R.D.R., E.C.T., S.C.V., G.S.W., and D.Z. provided or prepared samples’ in place of ‘M.N., B.P., M.L.P., R.D.R., E.C.T., S.C.V., G.S.W., and D.Z. provided or prepared samples.’The original version of the Supplementary Information associated with this Article contained an error in p. 4, which incorrectly read ‘Bat capture and handling were conducted under permits #7668-15 and 2492-17 from Dirección General de Vida Silvestre, and permits #17-16 and 21-17 from Secretaría de Gobernación.’ The correct version states ‘#7668-15, 2492-17 and 5409-18’ in place of ‘#7668-15, 2492-17’ and ‘#17-16, 21-17 and 20-18’ in place of ‘#17-16 and 21-17.’ The HTML has been updated to include a corrected version of the Supplementary Information.The original version of this Article contained an error in the email address of the corresponding author Steve Horvath, which was missing the terminal edu and should be [email protected] have been corrected in both the PDF and HTML versions of the Article
Strategies, Methods and Tools for Solving Long-term Transmission Expansion Planning in Large-scale Power Systems
No full textDriven by a number of factors, the electric power industry is expected to undergo a paradigm shift with a considerably increased level of variable energy sources. A significant integration of such sources requires heavy transmission investments over geographically wide and large-scale networks. However, the stochastic nature of such sources, along with the sheer size of network systems, results in problems that may become intractable. Thus, the challenge addressed in this work is to design efficient and reasonably accurate models, strategies and tools that can solve large-scale TEP problems under uncertainty. A long-term stochastic network planning tool is developed, considering a multi-stage decision framework and a high level integration of renewables. Such a tool combines the need for short-term decisions with the evaluation of long-term scenarios, which is the practical essence of a real-world planning. Furthermore, in order to significantly reduce the combinatorial solution search space, a specific heuristic solution strategy is devised. This works by decomposing the original problem into successive optimization phases.One of the modeling challenges addressed in this work is to select the right network model for power flow and congestion evaluation: complex enough to capture the relevant features but simple enough to be computationally fast. Another relevant contribution is a domain-driven clustering process of snapshots which is based on a “moments” technique. Finally, the developed models, methods and solution strategies have been tested on standard and real-life systems. This thesis also presents numerical results of an aggregated 1060-node European network system considering multiple RES development scenarios. Generally, test results show the effectiveness of the proposed TEP model, since—as originally intended—it contributes to a significant reduction in computational effort while fairly maintaining optimality of the solutions.Driven by several techno-economic, environmental and structural factors, the electric energy industry is expected to undergo a paradigm shift with a considerably increased level of renewables (mainly variable energy sources such as wind and solar), gradually replacing conventional power production sources. The scale and the speed of integrating such sources of energy are of paramount importance to effectively address a multitude of global and local concerns such as climate change, sustainability and energy security. In recent years, wind and solar power have been attracting large-scale investments in many countries, especially in Europe. The favorable agreements of states to curb greenhouse gas emissions and mitigate climate change, along with other driving factors, will further accelerate the renewable integration in power systems. Renewable energy sources (RESs), wind and solar in particular, are abundant almost everywhere, although their energy intensities differ very much from one place to another. Because of this, a significant integration of such energy sources requires heavy investments in transmission infrastructures. In other words, transmission expansion planning (TEP) has to be carried out in geographically wide and large-scale networks. This helps to effectively accommodate the RESs and optimally exploit their benefits while minimizing their side effects. However, the uncertain nature of most of the renewable sources, along with the size of the network systems, results in optimization problems that may become intractable in practice or require a huge computational effort. Thus, the challenge addressed in this work is to design models, strategies and tools that may solve large-scale and uncertain TEP problems, being computationally efficient and reasonably accurate. Of course, the specific definition of the term “reasonably accurate” is the key issue of the thesis work, since it requires a deep understanding of the main cost and technical drivers of adequate TEP investment decisions. A new formulation is proposed in this dissertation for a long-term planning of transmission investments under uncertainty, with a multi-stage decision framework and considering a high level of renewable sources integration. This multi-stage strategy combines the need for short-term decisions with the evaluation of long-term scenarios, which is the practical essence of a real-world planning. The TEP problem is defined as a stochastic mixed-integer linear programming (S-MILP) optimization, an exact solution method. This allows the use of effective off-the-shelf solvers to obtain solutions within a reasonable computational time, enhancing overall problem tractability. Furthermore, in order to significantly reduce the combinatorial solution search (CSS) space, a specific heuristic solution strategy is devised. In this global heuristic strategy, the problem is decomposed into successive optimization phases. Each phase uses more complex optimization models than the previous one, and uses the results of the previous phase so that the combinatorial solution search space is reduced after each phase. Moreover, each optimization phase is defined and solved as an independent problem; thus, allowing the use of specific decomposition techniques, or parallel computation when possible. A relevant feature of the solution strategy is that it combines deterministic and stochastic modeling techniques on a multi-stage modeling framework with a rolling-window planning concept. The planning horizon is divided into two sub-horizons: medium- and long-term, both having multiple decision stages. The first sub-horizon is characterized by a set of investments, which are good enough for all scenarios, in each stage while scenario-dependent decisions are made in the second sub-horizon. One of the first modeling challenges of this work is to select the right network model for power flow and congestion evaluation: complex enough to capture the relevant features but simple enough to be computationally fast. The thesis includes extensive analysis of existing and improved network models such as AC, linearized AC, “DC”, hybrid and pipeline models, both for the existing and the candidate lines. Finally, a DC network model is proposed as the most suitable option. This work also analyzes alternative losses models. Some of them are already available and others are proposed as original contributions of the thesis. These models are evaluated in the context of the target problem, i.e., in finding the right balance between accuracy and computational effort in a large-scale TEP problem subject to significant RES integration. It has to be pointed out that, although losses are usually neglected in TEP studies because of computational limitations, they are critical in network expansion decisions. In fact, using inadequate models may lead not only to cost-estimation errors, but also to technical errors such as the so-called “artificial losses”. Another relevant contribution of this work is a domain-driven clustering process to handle operational states. This allows a more compact and efficient representation of uncertainty with little loss of accuracy. This is relevant because, together with electricity demand and other traditional sources of uncertainty, the integration of variable energy sources introduces an additional operational variability and uncertainty. A substantial part of this uncertainty and variability is often handled by a set of operational states, here referred to as “snapshots”, which are generation-demand patterns of power systems that lead to optimal power flow (OPF) patterns in the transmission network. A large set of snapshots, each one with an estimated probability, is then used to evaluate and optimize the network expansion. In a long-term TEP problem of large networks, the number of operational states must be reduced. Hence, from a methodological perspective, this thesis shows how the snapshot reduction can be achieved by means of clustering, without relevant loss of accuracy, provided that a good selection of classification variables is used in the clustering process. The proposed method relies on two ideas. First, the snapshots are characterized by their OPF patterns (the effects) instead of the generation-demand patterns (the causes). This is simply because the network expansion is the target problem, and losses and congestions are the drivers to network investments. Second, the OPF patterns are classified using a “moments” technique, a well-known approach in Optical Pattern Recognition problems. The developed models, methods and solution strategies have been tested on small-, medium- and large-scale network systems. This thesis also presents numerical results of an aggregated 1060-node European network system obtained considering multiple RES development scenarios. Generally, test results show the effectiveness of the proposed TEP model, since—as originally intended—it contributes to a significant reduction in computational effort while fairly maintaining optimality of the solutions.QC 20160919</p
Introduce StarDetect to market: A roadmap towards small satellite application in Smart Tourism
No full textThe aerospace industry's global market rise considerably in recent years. StarDetect, founded in Beijing in 2020, is a startup focusing on small satellite technology, developing functional payloads and providing customised services within the needs of space astronomy or earth geography observation. However, due to the relatively short and immature development of China's small satellite commercial industry, the current satellite service targets is limited, and most of the end-users are government and research institutes. StarDetect's has to reach out to more potential customers and develop new satellite application scenarios. Therefore, the goal of this thesis is to investigate a new commercial market for StarDetect and formulate a strategy for its entry. The thesis employed the double diamond design process to provide structure for the creation process and obtain solutions by using iterative analysis. As the result, a roadmap is designed for StarDetect to enter the Smart Tourism market. In the first horizon, Destination Discovery Service based on mature technology is launched to open new businesses in the market with price penetration, to meet the needs of tourism project developers for quick access to destination information. And a 3D visualization service is available as an add-on value. In the second horizon, the Destination Environmental Monitoring service is introduced for increasing sales, which meet the demands of management organizations for monitoring the sustainability of natural destinations. At the same time, a website providing sustainable travel information to responsible travellers is offered, to develop StarDetect's brand recognition and build connections with potential consumers in preparation for the next horizon's B2C business. Finally, Horizon 3 continue to grow market segments by launching Disaster warning and Safety monitoring services. Meanwhile, StarDetect started to serve consumers directly by providing a one-stop service platform for outdoor adventure to capture new business opportunities.Strategic Product Desig
Nontrivial Pseudocharacters on Groups and Their Applications
No full textIn this paper questions of the existence of non-trivial pseudocharacters for different classes of groups and the most important applications of pseudocharacters are considered. We review the results obtained for non-trivial pseudocharacters of free group constructions. Pseudocharacter is the real functions f on a group G such that 1) |f(ab) − f(a) − f(b)| ≤ ε for some ε > 0 and for any a, b ∈ G and 2) f(xn) = nf(x) ∀n ∈ Z, ∀x ∈ G. Existence of non-trivial pseudocharacters implies the results for second group of bounded cohomologies and the width of verbal subgroups. Results of R.I. Grigorchuk, V.G. Bardakov, V.A. Fayziev and author on this topic are examined. Theorems about conditions of the existence of non-trivial pseudocharacters on such group objects as free products with amalgamation, HNN-extensions, group with one defining relation, anomalous products are given in the article. © 2018, Pleiades Publishing, Ltd
Nontrivial Pseudocharacters on Groups and Their Applications
No full textIn this paper questions of the existence of non-trivial pseudocharacters for different classes of groups and the most important applications of pseudocharacters are considered. We review the results obtained for non-trivial pseudocharacters of free group constructions. Pseudocharacter is the real functions f on a group G such that 1) |f(ab) − f(a) − f(b)| ≤ ε for some ε > 0 and for any a, b ∈ G and 2) f(xn) = nf(x) ∀n ∈ Z, ∀x ∈ G. Existence of non-trivial pseudocharacters implies the results for second group of bounded cohomologies and the width of verbal subgroups. Results of R.I. Grigorchuk, V.G. Bardakov, V.A. Fayziev and author on this topic are examined. Theorems about conditions of the existence of non-trivial pseudocharacters on such group objects as free products with amalgamation, HNN-extensions, group with one defining relation, anomalous products are given in the article. © 2018, Pleiades Publishing, Ltd
Digitalization of Operational Diagnostics of Functional Reserves and Assessment of Athletic Fitness
No full textЭрлих Вадим Викторович, доктор биологических наук, профессор, директор Института спорта, туризма и сервиса, Южно-Уральский государственный университет. 454080, г. Челябинск, проспект Ленина, 76. E-mail: [email protected], ORCID: 0000-0003-4416-1925.
Шибкова Дарья Захаровна, доктор биологических наук, профессор, главный научный сотрудник научно-исследовательского центра спортивной науки, Южно-Уральский государственный университет. 454080, г. Челябинск, проспект Ленина, 76. E-mail: [email protected], ORCID: 0000-0002-8583-6821.
Байгужин Павел Азифович, доктор биологических наук, ведущий научный сотрудник
научно-исследовательского центра спортивной науки, Южно-Уральский государственный университет. 454080, г. Челябинск, проспект Ленина, 76. E-mail: [email protected], ORCID: 0000-0002-5092-0943.
V.V. Erlikh, [email protected], ORCID: 0000-0003-4416-1925,
D.Z. Shibkova, [email protected], ORCID: 0000-0002-8583-6821,
P.A. Baiguzhin, [email protected], ORCID: 0000-0002-5092-0943
South Ural State University, Chelyabinsk, Russian FederationЦель: анализ подходов к цифровизации технологий оперативной диагностики функциональных резервов и оценки готовности организма спортсменов к соревновательной деятельности, обоснование модели многомерного анализа динамической структуры мобилизуемых резервов организма. Методология исследования. Использован теоретический анализ научных публикаций отечественных и зарубежных авторов за последние десять лет по разработке и внедрению цифровых технологий в области спортивной физиологии и медицины. Результаты. Аналитический обзор литературы свидетельствует, что в настоящее
время разработаны и внедрены сотни технологий оценки функционального состояния и резервов, реализованных во множестве программно-аппаратных диагностических комплексов и дистанционных регистраторов, большая часть которых решает частные задачи и не отражает полипараметрическую интеграцию подготовленности спортсмена к соревновательной деятельности; представлена авторская концептуальная модель многомерного анализа динамической структуры мобилизуемых резервов организма с последующим формированием состояния готовности спортсмена к соревновательной деятельности. Заключение. Концептуальная модель может служить основанием для создания единой цифровой
платформы на основе полипараметрической интеграции, которая объединит инновационные достижения в области оперативной оценки функционального состояния, мобилизации резервов и готовности организма спортсменов к эффективной соревновательной деятельности. Aim. The article aims at analyzing the approaches to digitalization of operational diagnostics of functional reserves, assessing the athletic fitness for competitive activity, substantiating a model of multivariate analysis of the dynamic structure of mobilized reserves. Materials and methods. A theoretical analysis of the scientific publications on the development and implementation of digital technologies in sports physiology and medicine written by domestic and foreign
authors over the past ten years has been conducted. Results. An analytical review of the literature indicates that hundreds of technologies for assessing the functional status and reserves introduced in a variety of software and hardware diagnostic systems and remote recorders have been developed and implemented, most of which solve particular problems and do not reflect the multiparameter integration of athletic fitness for competitive activity; the author presents a conceptual model of multidimensional analysis of the dynamic structure of mobilized reserves with the subsequent formation of athletic fitness for competitive activity. Conclusion. The conceptual model can serve as the basis for creating a unified digital platform based on multiparameter integration, which will combine innovative achievements in operational assessment of the functional status, mobilization of reserves and athletic fitness for competitive activity
New source for L-iditol and taxanes
No full textWe describe the first report of the recovery of L-iditol and Taxane from an angiosperm- Yunnanopilia longistaminata (W.Z.Li) C.Y.Wu et D.Z.Li (Opiliaceae). Two taxane compounds and L-iditol were isolated from the tender burgeon of Yunnanopilia longistaminata, and their structure were identified as Taxayunnansin B, Taxumairol E and L-iditol on the basis of NMR and MS spectrum, respectively. It is a new plant source for L-iditol and taxanes
annabellisa/PLANTPOPNET_genetics: PLANTPOPNET data and scripts v1.2
No full textDescription: R scripts for processing and analysing genetic and demographic data from Plantago lanceolata. Used in population genetics research by Annabel Smith and Yvonne Buckley, with the PLANTPOPNET network.
Author: Annabel Smith, except where indicated within the script.
Manuscript: Smith A.L., Hodkinson T.R., Villellas J., Catford J.A., Csergő A.M., Blomberg S.P., Crone E.E., Ehrlén J., Garcia M.B., Laine A.-L., Roach D.A., Salguero-Gómez R., Wardle G., Childs D.Z., Elderd B.D., Finn A., Munné-Bosch S., Baudraz M.E.A., Bódis J., Brearley F.Q., Bucharova A., Caruso C.M., Duncan R.P., Dwyer J.M., Gooden B., Groenteman R., Hamre L.N., Helm A., Kelly R., Laanisto L., Lonati M., Moore J.L., Morales M., Olsen S.L., Pärtel M., Petry W.K., Ramula S., Rasmussen P.U., Enri S.R., Roeder A., Roscher C., Saastamoinen M., Tack A.J.M., Töpper J.P., Vose G.E., Wandrag E.M., Wingler A. & Buckley Y.M. (2020). Global gene flow releases invasive plants from environmental constraints on genetic diversity. Proceedings of the National Academy of Sciences USA, www.pnas.org/cgi/doi/10.1073/pnas.1915848117
License: PLANTPOPNET genetics by Annabel Smith is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. Based on a work at https://github.com/annabellisa/PLANTPOPNET_genetics
Towards dynamic tension-compression asymmetry and relative deformation mechanisms in magnesium
No full textAuthor Accepted Manuscript (NSF Public Access)We present the first results of high-rate tension followed by compressive loading on a textured AZ31 alloy using a novel split-Hopkinson-pressure-bar (SHPB). The traditional-SHPB was modified in order to apply tension followed by compression along the rolling direction within few millisecond differences and a strain-rate of 103 s−1. The initial and post-deformed microstructure was examined by electron backscatter diffraction. The results reveal a reduced tension–compression asymmetry along with a shallower than the traditional sigmoidal-curve, indicating a significant influence of forward tensile loading on the subsequent compression behavior, manifested by the role of adiabatic-heating along with some unique deformation behavior.National Science Foundation (grant number 1554632
Estimating the spatial distribution of vocalizing animals from ambient sound spectra using widely spaced recorder arrays and inverse modelling
No full textAuthor Posting. © Acoustical Society of America, 2019. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 146(6), (2019): 4699, doi: 10.1121/1.5139406.The sound energy from marine mammal populations vocalizing over extended periods of time adds up to quasi-continuous “choruses,” which create characteristic peaks in marine sound spectra. An approach to estimate animal distribution is presented, which uses chorus recordings from very sparse unsynchronized arrays in ocean areas that are too large or remote to survey with traditional methods. To solve this under-determined inverse problem, simulated annealing is used to estimate the distribution of vocalizing animals on a geodesic grid. This includes calculating a transmission loss (TL) matrix, which connects all grid nodes and recorders. Geometrical spreading and the ray trace model BELLHOP [Porter (1987). J. Acoust. Soc. Am. 82(4), 1349–1359] were implemented. The robustness of the proposed method was tested with simulated marine mammal distributions in the Atlantic sector of the Southern Ocean using both drifting acoustic recorders [Argo (2018). SEANOE] and a moored array as acoustic receivers. The results show that inversion accuracy mainly depends on the number and location of the recorders, and can be predicted using the entropy and range of the estimated source distributions. Tests with different TL models indicated that inversion accuracy is affected only slightly by inevitable inaccuracies in TL models. The presented method could also be applied to bird, crustacean, and insect choruses.We would like to thank Randi Ingvaldsen and the Institute of Marine Research for providing supervision, funding (Research council of Norway Grant No. 228896), and scientific freedom to S.M., and the Office of Naval Research for funding D.Z. with Grant No. N00014-18-1-2811. We also thank the reviewers and Len Thomas for their feedback. The authors declare no competing interests.2020-06-3
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