Statistically, Asian Americans have significantly lower traffic accidents than any other minority group in the United States. However, there exists a stereotype that Asian Americans are a bigger risk on the road than any other ethnicity. This study explored the perspectives of Asian Americans, specifically Korean American women living in the city of Bellevue. Despite having enough English speaking skills to live comfortably in America, they had either a difficult time understanding roadway signs and posts, or if they did, it was not intuitive at first glance or within the time span necessary to make a decision on the road. The major problem that these Asian Americans felt was that in their homeland, many traffic decisions were made based on their instincts due to minimal roadway signs, or enforcement was so minimal that conforming to these traffic laws were not a priority to them. They reported that this mentality was reinforced more so because even when traffic laws were ignored, accident rates were low. This suggests that Asian Americans, though involved in less traffic accidents, make decisions less-rapidly, are confused on the road, or less readily conforming to traffic regulations. This study helps uncover a largely untapped field of study involving traffic safety within minority groups, and will further contribute to future research in similar topics.

A vast quantity of water is moving in the atmosphere under the direct influence of solar energy. Therefore, it is important to understand the energy balance to characterize the behavior of the water cycle of a particular region. Water gets back from ocean and land masses to the atmosphere through the process of evaporation and evapotranspiration (ET). Evapotranspiration is an important phenomenon in the water cycle for the estimation and evaluation of the available water resources. If we understand how ET is changing over space and time, then we can more accurately calculate the crop water requirement (CWR) at a high resolution for that region. This can help farmers in managing water resources very efficiently. Current research has difficulty in projecting how ET is going to change over different locations in the future. Therefore, through this research we are trying to understand the partition of the energy balance components and quantify them to help the water management in southern Idaho. To support this research, we will use the data from both Land Surface Hydrology Model and field observations and present the trends in surface energy balance components, including net radiation, latent (ET), sensible and ground heat fluxes. 

 As a river feeds into the ocean, a buoyant, laterally spreading, rapidly moving layer of fluid which runs seaward over the ocean surface (i.e., a river plume) is formed. At the interface between the fluids, shear stress creates turbulence, which causes mixing and plume deceleration. Additionally, pressure differences due to density differences and the plume surface slope create a pressure imbalance. The interplay of these and other processes are poorly understood. This lack of understanding is in contrast to the importance of river plumes dynamics: plume dynamics determine the ultimate concentration of contaminants and biological debris (notably red tide) in a larger (geostrophic) scale current which forms after the plume decelerates significantly. This geostrophic current runs along the coast and can transport contaminants to coastal marine ecosystems, beaches, and coastal communities. In order to predict the potential danger in the propagation of river contaminants along coasts, it is necessary to develop a quantitative understanding of plume dynamics. To this end, a momentum balance (an application of Newton’s Second Law to fluid flow) is currently being carried out. The relevant terms in this balance are the along-flow pressure gradient, the vertical turbulent interfacial stress gradient, and the total acceleration. Each of these terms can be constructed from velocity and density profiles which have been obtained for different experiments under both channelized and spreading conditions using particle image velocimetry (PIV) and particle laser-induced fluorescence (PLIF). By comparing the relative magnitudes of terms in the balance, a quantitative understanding of the importance of different dynamical processes will be obtained, and by comparing the form of the balance in channelized and spreading cases, a hypothesized relationship between spreading (which causes the fluid to collapse and accelerate) and turbulence/mixing (the magnitude of which is determined by the speed of the plume) will be investigated.

Membranes are used frequently in water filtration to remove bacteria and contaminants from fresh water. Natural organic matter (NOM) collects inside the permeable membrane, and causes resistance against the water flow. As NOM collects, more force is required to move water through the membrane, and the energy required to continue the process increases. When the pressure required to move water through the membrane has increased, the membrane has fouled. This project examines the filtration and adsorption of NOM in fresh water obtained from Lake Washington. Heated aluminum oxide particles (HAOPs) act as an adsorbent layer, trapping NOM and protecting the membrane from fouling. The HAOPs protect the membrane by collecting and removing NOM through deposition and backwash cycles. During deposition, twenty grams per meters squared (g/m²) of HAOPs are pumped inside a plastic, tubular membrane with a pore size of 2-3 microns. Lake water is then pumped through the membrane at a flux rate of 200 liters per meters squared per hour (lmh), and trans-membrane pressures are measured within the system. Trans-membrane pressure is measured to calculate the amount of pressure necessary to move water through the membrane. Samples are collected periodically throughout a 20 hour run time and analyzed for UV absorbance. UV absorbance measures the amount of light able to transmit through a sample of lake water; the amount of light that travels through the water correlates with the amount of contaminants or NOM that remain in the water. HAOPs successfully remove NOM molecules and protect the membrane, preventing it from fouling quickly. 

Photolysis of chlorine under sunlight results in generation of hydroxyl radical. Hydroxyl radical can in turn sensitize chlorine-resistant forms microorganisms such as Bacillus subtilis spores or Cryptospordium spp. occysts, and can make those microorganisms more vulnerable to chlorine. If the photolysis rate of chlorine and quantum yield of hydroxyl radical are known, microorganisms’ exposure to hydroxyl radical and free chlorine during a photochemically-enhanced chlorination process can in turn be derived. It is known that the decay of chlorine follows a first-order decomposition reaction under sunlight. Therefore, the reaction constant and half-life of chlorine can be computed according to first-order reaction equations. Understanding how pH and temperature affect half-life of chlorine can improve accuracy of prediction on required chlorine dosage in order to achieve a certain extent of disinfection in this photochemically enhanced chlorination process. The photolysis rate of chlorine under sunlight was investigated by determining chlorine’s half-life under various temperature and pH. Reaction solutions were irradiated by a Newport-Oriel solar simulator. Chlorine samples were taken at different time points and residual chlorine concentration was measured by DPD method. The results to be reported here showed that at the same temperature, the decay of chlorine was slower in a more acidic solution, which was due to the increasing ratio of [HOCl]/[OCl-]. Temperature also influenced chlorine’s photolysis rate: chlorine decayed more slowly in 5 °C than it did in 25°C. These findings will help to optimize the application of this disinfection process for inactivation of chlorine-resistant microorganisms.

More than 3000 landslides have been identified as occurring as a direct result of the March 11, 2011, Tohuko Earthquake, using Google Earth disaster satellite imagery (1 m resolution). Landslides were categorized into 5 types: disrupted, lateral spread, flow, rock fall, and block slides. These types were analyzed using ArcMap, a type of Geographical Information System (GIS) to map spatial patterns of landslides in relation to surficial geology, peak ground acceleration (PGA), distance to epicenter, and topography. The areal size versus frequency of the Japan landslides was also compared to distributions of landslides inventoried in previous studies. The Japan distribution was found to follow an inverse power law function; this is an extremely useful relationship because it allows us to “fill in” an incomplete inventory, and can have predictive value for landslides in areas that were not covered by the disaster imagery. In knowing how many landslides and where the susceptible areas are likely to occur, potential damage and injury can be avoided. Landslides can be dangerous and the disruption they cause in distribution of supplies especially aid after an event, this research can strengthen the ability for governments to plan for and find ways to diminish problems associated with such blockages. Further work can be done to determine how roadway systems and infrastructure can be safeguarded against failures to ensure life and property damage does not occur.

Polychlorinated Biphenyls (PCBs) are a group of man-made chemical species that were manufactured as refrigerants the mid 1900’s. Though now banned, PCBs are highly resistant to degradation and persist for many decades in the environment where they are known to have adverse affects on the health of organisms, and are a suspected carcinogen in humans. My research examines the impact of tidal cycles on the re-suspension and transport of PCBs adsorbed on sediments in the Duwamish River estuary. Aquatic systems contaminated with PCBs may lead to accumulation of the toxins in the tissues of aquatic organisms, such as shellfish and endangered Chinook salmon. Consumption of these valuable food resources poses a threat to human safety, and therefore it is critical to understand the spread of PCBs due to tidal oscillations in estuarine systems. In the Lower Duwamish Waterway, a salt wedge estuary with a sharp boundary between fresh and salt water, turbulence created by the relative motion of these bodies of water can move contaminated sediments to new areas. By testing a variety of water quality parameters, including total and dissolved organic carbon content, suspended solid content, salinity, pH, and PCB concentration, my work evaluates the likelihood that elevated PCB concentrations correspond to periods of maximum tidal turbulence and re-suspension of contaminated sediment from the river bottom. Aqueous and solid samples were collected from the estuary at different depths during various stages in the tidal cycle. I have measured key aforementioned water quality parameters according to standard methods, and developed a combined microwave-accelerated solvent and solid-phase extraction procedure for PCB recovery in particulate and aqueous phases. Using these methods, I will quantify the samples’ PCB concentrations using gas chromatography/mass spectrometry to determine sample composition, and attempt to correlate these measurements with suspended sediment and organic carbon concentrations.

Steel Plate Shear Walls (SPSWs) are structures used to mitigate damage to a building due to lateral forces caused by earthquakes. A literature review is being conducted on SPSWs to create a unified database that will be made public on the Network for Earthquake Engineering Simulation Website. The database will include information on Steel Plate Shear Wall tests, such as wall properties and information on drift levels for various repair states. Drift is a measurement of lateral displacement divided by total wall height. Repair states correspond to the values of drift at which a certain type of repair of the wall is required. Drift levels will be organized by their associated repair state to create fragility functions. Fragility functions are cumulative distribution functions that tell the probability of a SPSW reaching a specific damage state at a specific drift level. These functions can help engineers design SPSWs and predict what level of damage or repair is expected under a certain level of earthquake shaking.

There is a high need for transitional housing in areas affected by natural disasters, particularly transitional housing that is permanent, high performing, economical, and sustainable. Current solutions, predominantly large tents, do not provide a satisfactory living state for the tens of thousands of people displaced by these natural disasters. Alternate housing options have been developed and implemented, but the response of these alternatives under seismic loading has not been sufficiently studied. A promising alternative is the use of strategically stacked earthbags in combination with frictional material between the bags, strapping, and render for aesthetic purposes. The placement and configuration of these materials impacts the flexural and shear response of the entire housing system. Through modeling force versus deflection of various models, we can predict the response of the earthbag structure. Using strategic bag placements and placement of restraining components, the goal is to quantify the response of the structure. We anticipate that weaving strapping throughout the bags will provide more resistance to buckling and failure in the configurations discussed throughout this paper. By quantifying the relationship of materials and response, we can design an economical and viable transitional housing solution to respond more predictably under earthquake loading. The design of this structure can provide an economical, accessible, and easily constructible housing alternative.

          Disproportionate collapse is a phenomenon in which the localized failure of a small portion of a structure triggers the failure of adjoining members, resulting in damage disproportionate to the original cause. In Steel Gravity Framing Systems (SGFSs), connections between members are designed solely to support nominal gravity loading in shear, exemplifying a system which may be particularly vulnerable to collapse if subjected to unanticipated loading.  If unanticipated loading compromises a column’s ability to resist gravity loading in a SGFS, demands on the shear connections become significantly more complex. Under this scenario, gravity loading initially induces primarily shear and bending moment on the connections, which are resisted through friction and clamping forces and later through horizontal bearing forces at the bolt holes when the friction is overcome. As the beams rotate, the gravity loading becomes resolvable into components perpendicular and parallel to the beam axes, generating large tension forces in the connections. Thus, connections originally designed only to resist shear are subjected to a complex combination of bending moment, shear, and tension forces.  This research experimentally investigates the behavior of steel gravity framing connection subassemblages under loading consistent with a column losing its load carrying capacity in order to evaluate connection performance and system-level integrity of existing SGFSs. Furthermore, once the demands on the connections are adequately characterized, practical solutions to improve connection robustness and SGFS integrity can be developed.

Antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB) have been detected in many natural and engineered water systems, such as estuaries, surface waters, and drinking and waste water treatment plants. Although many ARB are likely to be inactivated during water treatment, their ARGs may survive treatment by means of protection with cell debris or adsorption on to particulate matter. This is a potential risk for human and animal health, as certain clinically-relevant bacterial populations can undergo horizontal gene transfer by means of natural transformation, which requires only intact, free DNA and a live recipient cell (no donor cell required). These risks can possibly be mitigated through optimization of disinfection processes. However, the current treatment processes focus on deactivating the viable microbes, not the ARGs. Our study focuses on the deactivation and degradation of ARGs in disinfection processes. Our data suggests that current CT (= oxidant concentration in mg/L * time of exposure in min) values for the use of free chlorine (10⁰ to 10¹) and ozone (10^-1 to 10⁰) in disinfection are sufficient to deactivate in vitro ARGs; however the CT values for chloramines (10² to 10³) are likely not able to deactivate the in vitro ARGs. In the case of in vivo ARGs, even higher CT values are likely to required, as cell debris can protect the genes. For example, our data show that a CT value of 90 mg/l*min of chlorine, which is a very high CT value, can deactivate all the cells, but has no effect on the genes inside.

Reactive halogen species (RHS, e.g., X·, X2·- and HOX), which can be generated during solar irradiation of sea water, can abiotically produce organohalogen compounds by reacting directly with natural organic matter (NOM). In order to obtain a better understanding of the mechanism involved in these systems, a novel technique that allows monitoring RHS production in sea water is required. For this purpose, I have performed a variety of tests to aid in the development of a highly-sensitive method for measuring RHS yields using the probe compound 3,5-dimethylpyrazole (DMPZ), which can rapidly and selectively form monohalogenated products by interacting with certain RHS. In this work, samples of artificial sea water containing DMPZ were irradiated in a 1700-W Xe arc lamp solar simulator for 48 hours. The concentrations of the main photochemical reaction byproducts (4-bromo-3,5-dimethylpyrazole and 4-iodo-3,5-dimethylpyrazole), which are formed in proportion to the concentration of RHS generated during irradiation, were determined by liquid chromatography with mass spectrometry (LC-MS). From this work, we have demonstrated that DMPZ is suitable for use as a probe of RHS. In addition, we have used this method to study the influence different chemical species (NO2-, NO3- , Fe3+, I- and natural organic matter) present in the water matrix on yields of halogenated DMPZ. Results of these experiments will be presented, and discussed with respect to likely relevance for natural environmental systems.

Currently, freight models at the state level use a four-step modeling approach, which generates trips based on origins, destinations, and land use. In the personal travel sector, models have started taking into consideration entire tours based on household demographics. Freight modeling uses this same approach despite situational differences. In an effort to improve freight modeling, this research aims to identify characteristics of freight carrier companies that determine distinct freight movements. A survey of licensed motor carriers was designed and conducted in Washington State and Oregon State. The identical surveys conducted in both states consisted of 33 questions. Respondents were asked questions regarding their vehicle fleet, locations served, times traveled, types of deliveries, and commodities. A total of 614 complete responses were gathered. An analysis of the data, using statistical software R and Excel, aims to reveal clusters of company types that can be distinguished by determining characteristics such as company size, commodity, and role in a supply chain. By identifying unique patterns among the dependent variable such as travel distance, travel times, and delivery style, the results can then be integrated into state models to more accurately predict freight vehicle routes.

This project explores the innate immunity of the earthworm species Eisenia fetida during development in context of its symbiotic relationship with Verminephrobacter eiseniae, a known bacterial symbiont. Innate immunity, unlike adaptive, has largely unspecific properties against foreign particles yet many organisms that possess only innate immunity manage to allow select beneficial symbionts to thrive within their body while at the same time defending against pathogenic infection. In this study I begin to explore involvement of innate immunity in the relationship between E. fetida and its symbiont V. eiseniae. This project examines expression of a common innate response, oxidative stress, in early stages of V. eiseniae colonization of its host E. fetida. We hypothesize that innate immunity activity is spatially separated from colonization of bacterial symbionts. To test this hypothesis, I will stain for nitric oxide synthase (NOS), an enzyme commonly involved in oxidative stress, during the development of E. fetida in the presence of V. eiseniae. I will then proceed to compare the location of NOS to the location of V. eiseniae. If the hypothesis is correct, then oxidative stress response in the worm eliminates foreign organisms everywhere except where the symbionts reside. On the other hand, if oxidative stress is at the same location as the known symbionts at the same time during development, then the oxidative stress may eliminate other foreign organisms except the symbionts, which have developed a mechanism for overcoming the stress. The results of this research can reveal how innate immunity overcomes the dilemma of accommodating symbionts. In addition, if E. fetida is particularly easy to work with for this type of experimentation, then E. fetida could prove to be an ideal model organism for studying innate immunity. Furthermore, insights into innate immunity may hold the key to new innovative ways of combating disease.

Droughts and floods are pervasive natural hazards. Accurate precipitation estimates are essential for model predictions. However, it is challenging to generate accurate precipitation estimates only using gage observation data, especially over data sparse regions. Satellite sensors, used in combination, have the potential to improve the accuracy, coverage, and resolution of precipitation estimates. We evaluate the Tropical Rainfall Measuring Mission (TRMM) Multi satellite Precipitation Analysis (TMPA) 0.25 degree real-time product in comparison with the TMPA gauge-adjusted research product for the period from January 2003 to June 2011 over Africa. We calculate the maximum dry period lengths for each water year based on both daily and monthly TMPA data. We also calculate several performance indicators including frequency bias index, probability of detection, false alarm ration and equitable threat score. From the results, we evaluate the spatial and temporal patterns of errors of the real-time product compared to the gauge-adjusted product. Specifically, we show spatial variability in monthly and annual precipitation bias in the real-time product and the performance indicators for select location distributed across the continent. We also demonstrate the effect that changes in the TMPA real-time algorithms have had on these performance metrics. This poster describes the TMPA algorithms, our evaluation methods, and our results, with particular attention to the error analysis over the central region of the African continent using daily TMPA data.

Electric vehicle infrastructure is the support network that allows electric vehicles (EVs) to travel farther than battery capabilities currently make possible. The infrastructure includes privately and publicly owned charging stations, upgraded electrical utilities capable of handling the output demanded by charging stations, and the internet technologies that give drivers the latest information on charging station locations and availability. This research investigated and developed a process to install a charging station on a roadway project in order to encourage expansion of electric vehicle infrastructure. This process could be recognized as a potential sustainable activity in the Greenroads Rating System. The rating system assigns points for completion of a number of sustainable activities on a roadway project that contribute to creating a "greener" road. Laying out such a process is especially challenging because it must remain applicable to many types of roadways in diverse environments, even with future advancements in electric vehicles, charging stations, and battery technologies. Two types of roadway projects were studied as cases: projects that have already installed charging stations and others that were considering installing charging stations. Through communication with professional design engineers on these projects and exploring numerous government EV infrastructure documents, preliminary findings determined that location characteristics, local markets for EVs, and local rules and regulations were the three key components to establishing EV infrastructure. Using these components, a short rubric was created, that allows project engineers to evaluate the feasibility of installing a charging station on a road project.

All solid materials have a stress limit beyond which cracks and ultimately fractures will develop; we are analyzing the possibility of uneven solar heating as a process that causes cracking. Research at the Universities of New Mexico and North Carolina drew attention to patterns of near vertical cracks in desert rocks, which known weathering processes cannot sufficiently explain. To investigate, temperature and strain data as well as cracking events were recorded using an instrumented boulder. We created a 3D-Finite-Element-simulation of the boulder incorporating thermal radiation, heat conduction, and thermo-mechanical stress analysis. Simulation provides the link between insolation and stresses, allowing us to assess size and shape effects on tensile stresses. We are validating our model by comparing measured and simulated temperature and strain data. As an example, we are calculating the maximum and minimum strain for each surface collection point and validating them against provided data. We expect to find that uneven heating from the diurnal cycle of the sun creates tensile stresses sufficient to cause cracking in these rocks. Future research will include a comprehensive data analysis concerning stress distribution and orientation within spherical boulders of various sizes, and an assessment of potential crack growth rates and crack orientation.

According to the 2011 Urban Mobility Report, roadway congestion cost a total of $101 billion dollars and a total delay of 4.8 billion hours in the US in 2010, with approximately 60% of the congestion occurring on freeways. Given the severity and economic costs of freeway congestion, strategies to mitigate congestion based on real-time data and cutting edge technologies have obtained broad attention. Integrated Corridor Management (ICM) is an emerging management strategy in this category. ICM aims to understand how non-recurrent congestion causes, such as incidents, affect both freeway and nearby arterial corridors, and how network-wide congestion could be mitigated by diverting traffic to nearby arterials with extra capacity. This study investigates the effectiveness of the ICM technology and possible impacts on local streets for the Seattle Department of Transportation. A microscopic simulation model was built in VISSIM (a software often utilized to model the study area and traffic behavior) to conduct what-if analyses under the ICM strategy. The model studies the SODO area network, which includes northbound I-5 and the nearby major parallel arterials. To simulate practical and reliable results, the model first needs to be calibrated to ensure the model output can replicate observed field data. The sensitivity analysis between different driving behavior parameters in VISSIM, such as headway time, standstill distance, and maximum deceleration for lane changing, and the modeled vehicle throughput was performed during the calibration process. Results of this research can be useful by providing logical rationale for how driving behavior parameters can be adjusted to achieve desired volume results. This specific calibrated model serves as the stepping-stone for future research in the ICM project, where dynamic routing is implemented to investigate how traffic is diverged during accidents within the study network.

Volatile organic compounds (VOCs) in indoor household air are carcinogens that many people are exposed to everyday. Examples of VOCs in the home are benzene, chloroform, and trichloroethylene. Genetically transformed plants are capable of degrading these VOCs by oxidizing them into less harmful compounds. The Strand lab has previously shown that poplar trees and tobacco, genetically transformed with cytochrome P450 2E1 (a rabbit gene expressed in the liver), successfully phytoremediated VOCs (phytoremediation is the use of plants in environmental treatment). My project at the Strand lab is to transform a houseplant with the same 2E1 gene, so people may raise this plant in their home to degrade indoor VOCs. Epipremnum aureum, a house ivy under the common name of pothos, was chosen for this project because the project follows the protocol for pothos transformation published by Kotsuka and Tada. Additionally, pothos does not flower, so the spread of the 2E1 gene can be kept in check. The project was executed in three steps: transformation, regeneration, and confirmation. The first part was to transform explants (pieces of pothos) by way of Agrobacterium infection, in which the bacteria insert the 2E1 gene into the pothos genome. The second step was to induce growth of calli in the explants, from which a new, genetically identical plant could be regenerated. The last step is to confirm that the new pothos was actually transformed and capable of degrading VOCs. This will be done through such tests as PCR, rtPCR, Western blot, and activity assays. I expect the pothos to be able to degrade VOCs as did the transgenic poplar and tobacco. These VOCs include trichloroethylene, vinyl chloride, chloroform, carbon tetrachloride, and benzene. If this result is not achieved, then future work may be devoted to find why the 2E1 gene is not compatible with pothos.