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Seabrook Elementary School Removal (5)
No full textText on back of photo reads "#5-12-17-96 Removal of Seabrook Elementary".One of five photographs (front and back) showing the removal of the old Seabrook Elementary School in December 1996
Construction (5)
No full textOne of ten photographs showing views of construction. Paper manufactured by Kodak
Environmental (in)justice and unequal burden: Race, income, and solid waste sites in Houston
No full textSince the 1980s, the environmental justice (EJ) movement, academics, and advocates have raised much awareness for EJ issues and concerns. Many EJ studies have found that environmental burdens such as waste sites, polluting industries, and other locally unwanted land uses are disproportionately located in low-income communities and minority communities. The goal of this study was to examine the location of Greater Houston’s municipal solid waste landfills (MSWLs) in relation to community race/ethnicity and income. The Houston Metropolitan Statistical Area (MSA) was the chosen study area based on prior EJ study findings and concerns. Data for MSWLs was acquired from Texas Commission on Environmental Quality (TCEQ) online databases. Data for racial/ethnic and income characteristics was acquired from the U.S. Census Bureau online databases. ArcGIS software was used to manage the data and analyze the location of the Houston MSA’s MSWLs and the racial/ethnic and income characteristics of nearby communities. The results of the analysis suggest that MSWLs in the Houston MSA are located in predominantly Hispanic/Latino communities, Black/African American communities, non-Hispanic White communities, lower-income and middle-income communities. Many communities across the nation endure an unequal burden from living near waste sites. There is significant importance in further study of the populations that live near MSWLs for both environmental justice concerns and public health concerns. Although state and federal environmental regulations aim to limit pollution, environmental pollution caused by MSWLs cannot be completely eradicated. MSWLs present numerous public health concerns for nearby communities including potential for air, land, and water contamination. There is a need for future research to examine the effects MSWLs have on nearby residents’ health and quality of life
Improving Reliability and Latency of High Critical Tasks in Mixed Criticality Systems through Task Rescheduling
Get PDFA Mixed Criticality System (MCS) consists of various hardware and software components executing tasks with different criticality levels. The criticality of a task is determined by its impact on the overall system output (e.g., safety critical and mission critical tasks or low critical and high critical tasks). In today’s world, such systems can be found almost everywhere including cars, airplanes, remotely piloted vehicles and so on. An MCS needs to be designed considering different criticality scenarios depending on the requirements of the operating environment. Significant amount of research has been dedicated to improve various parameters of MCSs such as reliability, performance, and power consumption.
In this thesis, we focus on improving the reliability and execution latency of high critical tasks in mixed criticality systems running on a Hardware/Software codesign environment. The system can run in two different operating modes: low criticality mode, which is the normal operating mode of the system, and high criticality mode. We propose two different algorithms: Reliability Priority Algorithm and Latency Priority Algorithm. In reliability priority approach, the algorithm schedules all tasks in the system and returns the final reliability and the latency of the system in low criticality operating mode. In high criticality mode, the algorithm gives priority to high critical (HC) tasks over low critical (LC) ones during the scheduling process. The LC tasks are scheduled in the gaps available considering the latency constraints. The algorithm returns the overall reliability of the system and the reliability of the HC tasks in both modes of operation. In latency priority approach, we prioritize the execution latency of HC tasks over their reliability. In the low criticality mode, the algorithm schedules the tasks to the fastest components available at the point of arrival. In the high criticality mode, HC tasks are scheduled before LC tasks in order to improve the latency of HC tasks.
The results of the experimental evaluation clearly show the viability of the proposed algorithms. The reliability priority algorithm increases the reliability of the HC tasks by 6.6% on the average and the latency priority algorithm improves the execution latency of the HC tasks by 23.8% on the average for the automatically generated task graphs
Improving Aviation Data Communication and Storage Security using Blockchain Based Approach
No full textData Security and integrity remains a major challenge for the aviation industry data storage. Many data breaches have happened in the past which has directly caused financial loss to airlines and indirect losses to their customers. Blockchain and its related approaches provide decentralized security and privacy, however yet they involve significant energy, delay, and computational overhead. Security and privacy remain a major challenge for data communication between an Air Controller tower(ACT) and Flights mainly due to the immense scale of data transfer and distributed nature of this Internet of things (IoT) network.
The thesis is divided into 2 parts. The first part is Aviation Data communication security wherein the model consists of three main components: Customized Digital Certificate (CC), Validator (Smart Contract), Storage (Blockchain Network). A set of new algorithms are proposed to outline various phases during communication and embedding message security. Each ACT and Flight need to be equipped with IoT devices and Validator (SC) that can send and receive validated messages and store them in the Blockchain network at both ends. This paper explores the communication realm and outlines Cryptography and Blockchain-based approaches. Extensive empirical work has been done to demonstrate that the propsed models are viable concerning confidentiality, integrity, and availability. The second part is demonstrated in paper two, wherein the model consists of 4 components: channel CA and Identity Manager, Smart contract (Validator), Channels, and Distributed Ledger. Different methods are proposed to demonstrate that the proposed models are viable concerning confidentiality, Authentication, Authorization and Data integrity
