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Establishing a Historical Fine-Resolution Urban Database from KH-9 HEXAGON MCS and PCS Imagery Including an Urban Landscape Map, Stereo Anaglyph Image and Digital Surface Model
Get PDFHistorical, fine-scale spatial information on urban regions such as heights, spatial patterns and categories are critical for various disciplines. However, obtaining such historical information prior to the year 2000 is challenging. Although declassified analog images from the KH‑9 HEXAGON (hereafter, KH-9)’s mapping camera system (MCS) and panoramic camera system (PCS) at meter to sub-meter resolutions during 1970s are available, the absence of camera meta parameters (e.g., focal length, extrinsics, lens distortion) and the single film-based panchromatic image format pose significant limitations. Herein, a multifaceted analytical framework is developed to reconstruct a historical fine-scale urban database from KH‑9 MCS and KH‑9 PCS images which relies on minimal technical information. For the KH‑9 MCS, a deep learning classification framework is proposed to retrieve historical urban landscape features from KH‑9 MCS imagery. Also ablation studies are proposed to examine the impacts of deep learning hyperparameters on historical urban landscape classification and to assess the efficiency of deep learning models in comparison with benchmark machine learning techniques. For the KH‑9 PCS, first a framework is developed using SuperPoint + SuperGlue (SPSG) models to create historical ground point controls (GCPs) from KH‑9 PCS for accuracy assessment purposes and estimating the exterior orientation of the stereo cameras. Structure from motion (SfM) techniques are adopted to create an ultra-fine spatial urban stereo-anaglyph image and digital surface model (DSM). Finally, ablation investigations are conducted to compare the performance of the developed techniques with benchmark approaches. Our results suggest that KH‑9 MCS and PCS images, when analyzed with appropriate methodologies, can significantly enhance the reconstruction of a historical fine-scale urban database. Moreover, both KH‑9 MCS and PCS images can contribute to revealing super-urbanization (i.e., unprecedented urban development) including super-new urban development and super-urban redevelopment as well as super-urban no-change (i.e., stable over the four decades, 1975-2023)
Mg Substitution Improves the Surface Stability of High‐Voltage Spinel Cathodes under Accelerated Aging Conditions
Get PDFLiNi0.5Mn1.5O4 (LNMO) cathodes offer a cobalt‐free, high‐voltage alternative to current state‐of‐the‐art Li‐ion battery cathodes, and are particularly well‐suited for high‐power applications due to their 3D lithium‐ion pathways and structural stability. However, degradation of commercial electrolytes at high voltages exacerbates capacity decay, as instability at the cathode surface causes active material loss, surface reconstructions, thickening surface layers, and increases in internal cell resistance. Cationic substitution has been proposed to enhance surface stability, thus limiting capacity decay. Here, we demonstrate the stabilizing effect of Mg on the LNMO cathode surface, which is most evident during the early stages of cycling. This study indicates that improved O 2p‐TM 3d hybridization in Mg‐substituted LNMO, facilitated by Li‐site defects, leads to the formation of a stable surface layer that is corrosion‐resistant at high voltage. Examination of Fe‐substituted and unsubstituted LNMO further confirms that the surface stability is uniquely enabled by Mg substitution. This work offers valuable insights into surface design for reducing degradation in high‐voltage spinel cathodes
It's Up for Debate: A Review of Seminal Ideas and Controversies in Statistics by Roderick J. A. Little
Get PDFWhose border, which crisis? Illiberalism and the (re)nationalization of Poland’s eastern frontier, 2015-2022
No full textThis chapter explores the political contestations around Poland’s eastern borders with Belarus and Ukraine in the years 2021-22, situating them within the context of the post-1989 history of the transformation of Poland’s eastern border into the eastern external boundary of the European Union. In 2004, Poland’s eastern border became part of the larger perimeter of the European Union’s “area of freedom, security and justice” and the Polish Border Guard was enlisted in the task of protecting not just Poland’s territory, but also this larger area, with significant consequences for the borderland and beyond. In the chapter, I revisit some of the original tensions accompanying EU accession and the Europeanization of Poland’s eastern borders, before showing how the authorities came to interpret the task of “protecting Europe” following the illiberal turn in Polish politics in 2015, and how their actions developed in 2021-22, in the context of rising geopolitical tensions in the region and Russia’s invasion of Ukraine. Arguing that in the early 21st century most border politics are simultaneously local and global, domestic and European, the chapter asks what can we learn from the events on Poland’s borders about EU bordering practices within the context of Europe’s so-called “geopolitical turn”
Sustainability Matters : Company SDG Scores Need Not Have Size, Location, and ESG Disclosure Biases
Get PDFThis article examines potential biases in SDG scores, which assess companies’ alignment with the 17 UN Sustainable Development Goals. Known biases in ESG (environmental, social, and governance) ratings—such as size, location, and disclosure effects—raise concerns about their reliability in measuring corporate sustainability and informing sustainable investing strategies. Conversely, the authors find a slight negative correlation between company size and SDG scores, though this is economically insignificant. Firms in emerging markets exhibit marginally higher SDG alignment compared to those in developed markets, indicating an absence of location bias. These findings remain robust when accounting for a company’s capacity to disclose ESG data. The authors’ results imply that SDG-aligned investment portfolios can avoid biases commonly associated with sustainability ratings. Furthermore, they challenge the notion that company size, location, or disclosure resources are primary drivers of corporate sustainability performance
Measuring Discrepancies in Attack Surfaces Generated by Internet Intelligence Platforms
No full textIn response to the growing threat of cyber-attacks, there is a demand to understand modern, complex attack surfaces. To achieve this, different Internet Intelligence Platforms (IIPs) can be used. In this work, we show there are differences in the attack surfaces created using three IIPs: Shodan, Censys, and ZoomEye. Our results show these discrepancies manifest in the size and temporal characteristics of the identified attack surfaces. This could lead to organisations and decision makers potentially being misinformed about their true attack surface. These findings point towards the need for further research focused on understanding these discrepancies
Nanobody-based recombinant antivenom for cobra, mamba and rinkhals bites
Get PDFEach year, snakebite envenoming claims thousands of lives and causes severe injury to victims across sub-Saharan Africa, many of whom depend on antivenoms derived from animal plasma as their sole treatment option1. Traditional antivenoms are expensive, can cause adverse immunological reactions, offer limited efficacy against local tissue damage and are often ineffective against all medically relevant snake species2. There is thus an urgent unmet medical need for innovation in snakebite envenoming therapy. However, developing broad-spectrum treatments is highly challenging owing to the vast diversity of venomous snakes and the complex and variable composition of their venoms3. Here we addressed this challenge by immunizing an alpaca and a llama with the venoms of 18 different snakes, including mambas, cobras and a rinkhals, constructing phage display libraries, and identifying high-affinity broadly neutralizing nanobodies. We combined eight of these nanobodies into a defined oligoclonal mixture, resulting in an experimental polyvalent recombinant antivenom that was capable of neutralizing seven toxin families or subfamilies. This antivenom effectively prevented venom-induced lethality in vivo across 17 African elapid snake species and markedly reduced venom-induced dermonecrosis for all tested cytotoxic venoms. The recombinant antivenom performed better than a currently used plasma-derived antivenom and therefore shows considerable promise for comprehensive, continent-wide protection against snakebites by all medically relevant African elapids
How do entrants build market share? : The role of demand frictions
Get PDFWe construct a new data set to show that successful entrants in the consumer food sector build market share by adding new customers. Entrants reach new customers by entering more geographical markets, placing their product in more stores in these markets, and for a positively selected subset of firms, by advertising direct to customers. These activities are costly and are associated with persistent increases in quantities, but there are no differences in markups between new and mature markets. This confirms a central role for marketing and advertising in overcoming demand-side frictions that slow firm growth
