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Comparison Of Different Drought Monitoring Indices In Different Climatic Conditions In Iran, Samira Rahnama, Ali Shahidi, Mostafa Yaghoobzadeh, Ali Akbar Mehran

Faculty Research, Scholarly, and Creative Activity

This study evaluates drought in different climate zones (Rasht, Shiraz, and Birjand) in Iran, using meteorological, agricultural, and remote sensing drought indices. For this purpose, NDVI, SAVI, and SR were extracted from Landsat images for 2002 and 2014–2020. Then, these indices were compared with the SPI, SPEI, and PDSI. The results indicate an increase in drought and a decrease in vegetation cover in the study area. In Rasht, where the vegetation cover is high, NDVI and SAVI were equal. In Shiraz and Birjand, where the soil effect is more significant, the distance between these two indices increased, which shows that …

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[Review Of] Abolition Geography, By Ruth Wilson Gilmore, Jennifer Rycenga

Faculty Research, Scholarly, and Creative Activity

No abstract provided.

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Fuzzy Similarity Analysis Of Effective Training Samples To Improve Machine Learning Estimations Of Water Quality Parameters Using Sentinel-2 Remote Sensing Data, Alireza Taheri Dehkordi, Mohammad Javad Valadan Zoej, Ali Mehran, Mohsen Jafari, Amir Masoud Chegoonian

Faculty Research, Scholarly, and Creative Activity

Continuous monitoring of water quality parameters (WQPs) is crucial due to the global degradation of water quality, primarily caused by climate change and population growth. Typically, machine learning (ML) models are employed to retrieve WQPs, but they require a large amount of training samples to accurately capture the data relationships. Even with sufficient training data, discrepancies still exist between values of predicted and in-situ WQPs. This study proposes a fuzzy similarity analysis (FSA) technique to enhance ML estimates of WQPs by using the prediction errors in effective training samples. The method was successfully applied to retrieve turbidity (Turb) and specific …

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Access To Digital Finance: Equity Crowdfunding Across Countries And Platforms, Saul Estrin, Susanna Khavul, Alexander S. Kritikos, Jonas Löher

Faculty Research, Scholarly, and Creative Activity

Financing entrepreneurship spurs innovation and economic growth. Digital financial platforms that crowdfund equity for entrepreneurs have emerged globally, yet they remain poorly understood. We model equity crowdfunding in terms of the relationship between the number of investors and the amount of money raised per pitch. We examine heterogeneity in the average amount raised per pitch that is associated with differences across three countries and seven platforms. Using a novel dataset of successful fundraising on the most prominent platforms in the UK, Germany, and the USA, we find the underlying relationship between the number of investors and the amount of money …

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Marine Protection And Environmental Forcing Influence Fish-Derived Nutrient Cycling In Kelp Forests, June Shrestha, Joseph R. Peters, Jennifer E. Caselle, Scott L. Hamilton

Faculty Research, Scholarly, and Creative Activity

Animal consumers excrete dissolved inorganic nitrogen, an essential nutrient for regulating primary production and macroalgal growth in the ocean. Often overlooked in attempts to explain kelp forest productivity, relatively little is known about the role of consumers in nutrient cycling in temperate systems, such as the magnitude of nutrients excreted and the factors that influence spatial and temporal variability in consumer-derived nutrients. To investigate the supply of ammonium (NH4+) excreted by the dominant members of the nearshore rocky reef fish community, we combined empirically-measured relationships between excretion rate and body mass with data on fish density and size structure from …

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Mitigating Risk: Predicting H5n1 Avian Influenza Spread With An Empirical Model Of Bird Movement, Fiona Mcduie, Cory T. Overton, Austen A. Lorenz, Elliott L. Matchett, Andrea L. Mott, Desmond A. Mackell, Joshua T. Ackerman, Susan E.W. De La Cruz, Vijay P. Patil, Diann J. Prosser, John Y. Takekawa, Dennis L. Orthmeyer, Maurice E. Pitesky, Samuel L. Díaz-Muñoz, Brock M. Riggs, Joseph Gendreau, Eric T. Reed, Mark J. Petrie, Chris K. Williams

Faculty Research, Scholarly, and Creative Activity

Understanding timing and distribution of virus spread is critical to global commercial and wildlife biosecurity management. A highly pathogenic avian influenza virus (HPAIv) global panzootic, affecting 600 bird and mammal species globally and over 83 million birds across North America (December 2023), poses a serious global threat to animals and public health. We combined a large, long-term waterfowl GPS tracking dataset (16 species) with on-ground disease surveillance data (county-level HPAIv detections) to create a novel empirical model that evaluated spatiotemporal exposure and predicted future spread and potential arrival of HPAIv via GPS tracked migratory waterfowl through 2022. Our model was …

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Next Steps For Assessing Ocean Iron Fertilization For Marine Carbon Dioxide Removal, Ken O. Buesseler, Daniele Bianchi, Fei Chai, Jay T. Cullen, Margaret Estapa, Nicholas Hawco, Seth John, Dennis J. Mcgillicuddy, Paul J. Morris, Sara Nawaz, Nishioka, Anh Pham, Kilaparti Ramakrishna, David A. Siegel, Sarah R. Smith, Deborah Steinberg, Kendra A. Turk-Kubo, Benjamin S. Twining, Romany M. Webb

Faculty Research, Scholarly, and Creative Activity

There are many potential approaches to marine carbon dioxide removal (mCDR), of which ocean iron fertilization (OIF) has the longest history of study. However, OIF studies to date were not primarily designed to quantify the durability of carbon (C) storage, nor how wise OIF might be as an mCDR approach. To quantify C sequestration, we introduce a metric called the “centennial tonne,” defined as 1,000 kg of C isolated from atmospheric contact for on average at least 100 years. We present the activities needed to assess OIF from a scientific and technological perspective, and additionally, how it might be responsibly …

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Towards A Context-Contingent Stage Theory Of Entrepreneurial Opportunity: Introducing The Petii Model, Xiaohong Iris Quan

Faculty Research, Scholarly, and Creative Activity

Understanding opportunity is a crucial aspect of entrepreneurship research. Existing studies have extensively examined individual factors in facilitating entrepreneurial activities such as new venture creation. Although there are some discussions on contextual factors, few connect context with the origin of entrepreneurship—opportunity. Recognising the objectivity of entrepreneurial opportunity, this theoretical article first proposes two types of opportunities—innovative opportunity and imitative opportunity—to understand the nature of opportunity. It then proposes a systematic framework—the PETII (Population, Economic status, Technological advancement, Industry life cycle, Institutions) model—to analyse the role of context in the distribution of opportunity. Furthermore, it examines how both objective contextual factors …

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Full-Text Articles in Entire DC Network

Comparison Of Different Drought Monitoring Indices In Different Climatic Conditions In Iran, Samira Rahnama, Ali Shahidi, Mostafa Yaghoobzadeh, Ali Akbar Mehran

Faculty Research, Scholarly, and Creative Activity

[Review Of] Abolition Geography, By Ruth Wilson Gilmore, Jennifer Rycenga

Faculty Research, Scholarly, and Creative Activity

Fuzzy Similarity Analysis Of Effective Training Samples To Improve Machine Learning Estimations Of Water Quality Parameters Using Sentinel-2 Remote Sensing Data, Alireza Taheri Dehkordi, Mohammad Javad Valadan Zoej, Ali Mehran, Mohsen Jafari, Amir Masoud Chegoonian

Faculty Research, Scholarly, and Creative Activity

Access To Digital Finance: Equity Crowdfunding Across Countries And Platforms, Saul Estrin, Susanna Khavul, Alexander S. Kritikos, Jonas Löher

Faculty Research, Scholarly, and Creative Activity

Marine Protection And Environmental Forcing Influence Fish-Derived Nutrient Cycling In Kelp Forests, June Shrestha, Joseph R. Peters, Jennifer E. Caselle, Scott L. Hamilton

Faculty Research, Scholarly, and Creative Activity

Faculty Research, Scholarly, and Creative Activity

Faculty Research, Scholarly, and Creative Activity

Towards A Context-Contingent Stage Theory Of Entrepreneurial Opportunity: Introducing The Petii Model, Xiaohong Iris Quan

Faculty Research, Scholarly, and Creative Activity