Multi-task learning method using gradient descent with applications, A

2021 Spring.Includes bibliographical references.There is a critical need to develop classification methods that can robustly and accurately classify different objects in varying environments. Each environment in a classification problem can contain its own unique challenges which prevent traditional classifiers from performing well. To solve classification problems in different environments, multi-task learning (MTL) models have been applied that define each environment as a separate task. We discuss two existing MTL algorithms and explain how they are inefficient for situations involving high-dimensional data. A gradient descent-based MTL algorithm is proposed which allows for high-dimensional data while providing accurate classification results. Additionally, we introduce a kernelized MTL algorithm which may allow us to generate nonlinear classifiers. We compared our proposed MTL method with an existing method, Efficient Lifelong Learning Algorithm (ELLA), by using them to train classifiers on the underwater unexploded ordnance (UXO) and extended modified National Institute of Standards and Technology (EMNIST) datasets. The UXO dataset contained acoustic color features of low-frequency sonar data. Both real data collected from physical experiments as well as synthetic data were used forming separate environments. The EMNIST digits dataset contains grayscale images of handwritten digits. We used this dataset to show how our proposed MTL algorithm performs when used with more tasks than are in the UXO dataset. Our classification experiments showed that our gradient descent-based algorithm resulted in improved performance over those of the traditional methods. The UXO dataset had a small improvement while the EMNIST dataset had a much larger improvement when using our MTL algorithm compared to ELLA and the single task learning method

Lack of Cybersecurity in the United States’ Critical Infrastructure

Technology has revolutionized the nature of information, remote control, and communication itself, but it has also brought with it tangible dangers. Top minds in the United States, as well as the rest of the world, have seen those dangers and dedicated their work to mitigate them, developing the ideas and policies necessary to protect the nation from those dangers, and yet the actual implementation of safety measures within the nation lags behind. In the meantime, as U.S. critical infrastructure remains woefully unprotected, the nation opens itself up to a plethora of cyber-attacks. These attacks can cause damage in many ways. There are the obvious, tangible effects like costing trillions of dollars [1], poisoning water supplies to cause illness [2], or causing power outages [3], but we must also consider more subtle, social damages caused as well, such as losing trust, questioning the legitimacy of polling machines, or losing a sense of security in general. Regardless of the damage caused, it is clear that these attacks cannot be allowed to continue, and the United States already has a number of policies and strategies in place to defend itself and its critical infrastructure. However, despite being theoretically applicable and effective, the nation routinely sees them go unimplemented even as preventable attacks repeatedly succeed. What is it about the current U.S. policy that leaves it so vulnerable, and how can it be remedied? This brief addresses the question and offers a recommendation

Analysis Concerning the Disaster of the Forest: A Theoretical and Practical Approach: Working Paper Series--04-09

The explosion of serious forest fires in the Rocky Mountain West in recent years has opened the public eye to the unhealthy condition of forests. The extended drought has combined with dense forest conditions to make many residents of rural Arizona quite fearful of the possibility of additional fires. The public interest has even resulted in federal policy changes known as the Healthy Forests Initiative, which has, of course, stimulated increased public discussion. In order to find solutions to the problem, as based on Norgaard, Smith and Jacobs, society must create new ways of organizing and doing. This article explores possible market-based solutions as the one of the available practical remediation processes. Utilizing the forest restoration and engineering literature, we believe that a new forest-based industry founded on the concepts of science-based forest management and ecological sustainability is the logical solution in a market-based economy

Adapting Appropriation Water Law to Accommodate Equitable Consideration of Instream Flow Uses

The increasing public interest in naturally flowing streams has fostered efforts to obtain their protection under existing state water laws. In this study, the water laws of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming were examined and compared 1) with each other, and 2) against a set of aleitn criteria, to assess shortcomings in accommodating instream flow protections. It was determined that the appropriation system has the essential features of and ambodies legal principles that should allow the accommodation of instream flow values but, at this time, purchase of existing rights or the exercise of governmental reservation/withdrawal/appropriation authorities seem to be the primary options. Legislative, judicial, and adminsitrative strategies for protecting instream flows apart from the normal appropriation process were reviewed. Certain legislative and administrative strategies hold premise as supplementary to the standard appropriation procedure. Likewise, private sector strategies utilizing contracts, easements, purchase of development rights, etc., need to be more thoroughly considered. Where instream flow protections do not justify preemptive rights and strategies, and if hydrologic imperatives are properly observed, the state administered appropriation systems can accommodate the instream flow needs. However, the need for better technical information for establishing benficial need for the many instream values, and for use in projecting the biologic-hydrologic consequences of particular instream flow regimes remains a stumbling block to the accommodation process