Engineering Commons^™

A Comparison Of Zinc Levels In Runoff From Rubberized Hot Mix Asphalt And Conventional Pavement, Peter A. Duin

Cal Poly Humboldt theses and projects

High levels of dissolved zinc in water bodies can be toxic to aquatic organisms. There are currently over 40 waterways in California that have on occasion been in exceedance of Clean Water Act minimum toxicity threshold standards for zinc. Recycled tires that contain 1-2% zinc by mass are commonly used in California paving formulations known as Rubberized Hot Mix Asphalt (RHMA). The addition of tires to RHMA increases the zinc content of the pavement in comparison to conventional HMA. This research assesses the zinc content and leaching rate of RHMA in field and laboratory settings to estimate its contribution of …

Electrification Of Domestic Hot Water To Aid The Integration Of Renewable Energy In The California Grid, Alejandro Cervantes

Cal Poly Humboldt theses and projects

Water heating in residential buildings, also known as domestic hot water (DHW), is the third largest use of energy after appliances and space conditioning. About 90% of the residential buildings in the state use natural gas fueled water heaters, 6% use electricity, and a small percent use liquefied petroleum gas (LPG) or solar water heaters. The current energy use associated with residential water heating is small relative to the total amount of energy consumption in the residential building sector, but it is still a contributor of greenhouse gas (GHG) emissions. Improving hot water systems can be beneficial for bill customer …

Cost-Benefit Analysis Of Replacing Lpg Stoves With Induction Stoves In Rural Households Of Kavre District Nepal, Grishma Raj Dahal

Cal Poly Humboldt theses and projects

Nepal imports nearly 260,000 tons of Liquified Petroleum Gas (LPG) and other fossil fuels annually from India. This fuel dependency is one of the main reasons for Nepal’s trade deficit with India. The Government of Nepal has recently started promoting electric induction stoves for cooking as an alternative to LPG. Induction stoves are pollution free at the point of use, and they are meant to reduce Nepal's dependence on LPG.

This study includes a cost-benefit analysis for replacing LPG stoves with induction stoves for households in rural areas of Kavre District, Nepal. The study involved the use of data for …

Sediment Yield In Salmon Creek After Decommissioning Logging Roads, Northern Humboldt County, California, Malia S B Gonzales

Cal Poly Humboldt theses and projects

Salmon Creek watershed is located in the Headwaters Forest Reserve in northern California and is known for the ecological value of its old-growth redwood forest, high biodiversity, and sensitive habitat for endangered species. The Bureau of Land Management primarily manages the Reserve. The land-use history of the Upper Salmon Creek watershed includes extensive timber harvest and road development. Watershed restoration in the Upper Salmon Creek watershed started in 2000 with the primary goal for the Reserve to protect and recover ecologic diversity and threatened native species. Since then, of the 23 miles, 13.5 miles of logging roads and 101 stream …

Evaluation Of 1-D And 2-D Hydraulic Models For Designing And Assessing Fullspan Stream Crossings, Alyssa Sachiko Virgil

Cal Poly Humboldt theses and projects

This project compared design decisions and hydraulic analyses of full-span stream crossings using one- and two-dimensional (1-D and 2-D) hydraulic models. The project was initiated by the California Department of Transportation’s interest in moving from 1-D to 2-D hydraulic modeling and by the Federal Highways Administration’s support for adopting SRH-2D (Sedimentation and River Hydraulics-2D developed by the US Bureau of Reclamation) in Aquaveo, LLC’s Surface-water Modeling System as their standard design model. Two-dimensional hydraulic models calculate more detailed water depths and velocities than 1-D models, which can better identify fish passage conditions, areas of potential scour or deposition, and aquatic …

Multiple Criteria Decision-Making Approach To Support Timber Transportation Planning – Case Study In Brazil, Marinna Lopes Ferreira Gomes

Cal Poly Humboldt theses and projects

Timber transportation is one of the costliest activities for a forest company in Brazil and in many other countries, and it is a determining factor for the success of the forest enterprise. Thus, decision support tools are commonly used as methods to reduce these costs. The purpose of this study was to develop and analyze mathematical models to define the weekly timber transport schedule based on the monthly demands of the customers. The goal is to minimize the operational costs of forest transportation related to distances, timber freshness and road qualities. The decision process was made in two steps; the …