Physical Sciences and Mathematics Commons^™

Historical Tsunami Observability For Izu–Bonin–Mariana Sources, Walter Szeliga, Rachelle Reisinger, Breanyn T. Macinnes

Geological Sciences Faculty Scholarship

The Izu–Bonin–Mariana Subduction System (IBM) is one of the longest subduction zones in the world with no instrumental history of shallow focus, great earthquakes (Mw > 8). Over the last 50 years, researchers have speculated on the reason for the absence of large magnitude, shallow seismicity on this plate interface, exploring factors from plate age to convergence rate. We approach the question from a different point of view: what if the IBM has hosted great earthquakes and no documentable evidence was left? To address the question of observability, we model expected tsunami wave heights from nine great earthquake scenarios on the …

Contra-Thermodynamic Halolactonization Of Lactam-Tethered 5-Aryl-4(E)-Pentenoic Acids For The Flexible And Stereocontrolled Synthesis Of Fused Lactam-Halolactones, Timothy K. Beng, Claire Borg, Morgan J. Rodriguez

All Faculty Scholarship for the College of the Sciences

Halolactonization of alkenoic acids enables the construction of oxygen-heterocycles via intramolecular halonium-induced nucleophilic addition. Although the literature is currently inundated with halolactonizations of 5-aryl-4(E)-pentenoic acids that predictably afford the 6-endo cyclization adducts, methods that reliably alter the innate regioselectivity bias to instead deliver the thermodynamically less favored 5-exo cyclization products are relatively rare. Here, we attempt to bridge this gap and have found mild conditions for contra-thermodynamic halolactonization of lactam-tethered 5-aryl-4(E)-pentenoic acids that lead to the formation of trans-fused lactam-γ-lactones. The natural proclivity for these 5-aryl-4(E)-pentenoic acids to undergo 6-endo cyclization is overridden and 5-exo-trig cyclization predominates. The success of …

Sea Level Rise Estimation On The Pacific Coast From Southern California To Vancouver Island, Xiaoxing He, Jean-Philippe Montillet, Rui Fernandes, Timothy I. Melbourne, Weiping Jiang, Zhengkai Huang

Geological Sciences Faculty Scholarship

Previous studies have estimated the sea level rise (SLR) at various locations on the west coast of the USA and Vancouver Island in Canada. Here, we construct an entire SLR profile from Vancouver Island in the Pacific Northwest to San Diego in Southern California. First, we process global navigation satellite system (GNSS) measurements at 405 stations blanketing the whole coast to generate a profile of vertical land motion (VLM) known to bias century-long tide gauge (TG) measurements recording relative SLR (RSLR). We are then able to estimate the absolute SLR (ASLR) by correcting the SLR with the VLM. Our study …

Developing Research Data Management Services In A Regional Comprehensive University: The Case Of Central Washington University, Ping Fu, Maurice Blackson, Maura Valentino

Library Scholarship

This study aims to analyze the needs of researchers in a regional comprehensive university for research data management services; discuss the options for developing a research data management program at the university; and then propose a phased three-year implementation plan for the university libraries. The method was to design a survey to collect information from researchers and assess and evaluate their needs for research data management services. The results show that researchers’ needs in a regional comprehensive university could be quite different from those of researchers in a research-intensive university. Also, the results verify the hypothesis that researchers in the …

Weighted Incremental–Decremental Support Vector Machines For Concept Drift With Shifting Window, Honorius Gâlmeanu, Răzvan Andonie

Computer Science Faculty Scholarship

We study the problem of learning the data samples’ distribution as it changes in time. This change, known as concept drift, complicates the task of training a model, as the predictions become less and less accurate. It is known that Support Vector Machines (SVMs) can learn weighted input instances and that they can also be trained online (incremental–decremental learning). Combining these two SVM properties, the open problem is to define an online SVM concept drift model with shifting weighted window. The classic SVM model should be retrained from scratch after each window shift. We introduce the Weighted Incremental–Decremental SVM (WIDSVM), …

Monitoring Whitebark Pine Stand Health In The Central Washington Cascades, Nancy H. Parra, Teresa J. Lorenz, Taza D. Schaming, Alison Scoville

Student Published Works

Whitebark pine (Pinus albicaulis) plays a vital role in colonizing newly disturbed areas, providing shade for other tree species to germinate, and supplying food for a variety of birds and mammals, such as Clark’s Nutcrackers (Nucifraga columbiana) and grizzly bears (Ursus arctos horribilis). Decline of whitebark pine populations has been attributed to several factors, including white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae) outbreaks, and fire exclusion. In 2009, the U.S. Forest Service began to install permanent plots in whitebark pine stands in Washington and Oregon as …

Nitrogen Fixation Rates In Forested Mountain Streams: Are Sediment Microbes More Important Than Previously Thought?, Erica A. H. Bakker, Carmella Vizza, Clay Arango, Sarah S. Roley

Biology Faculty Scholarship

1. Biological nitrogen (N) fixation, the microbial conversion of N₂ gas to ammonia, makes N available to food webs. Low-N streams often have a high relative abundance of N-fixing taxa, suggesting that N fixation is an important N source in these systems. Despite this potential, stream N fixation has not been well-characterised, particularly compared to lakes and marine environments. One unknown is the relative contributions of various N-fixing organisms, particularly heterotrophic microbes.
2. In low-N streams in the Cascade Mountains (Washington, USA), three groups of N-fixers predominate: cyanobacteria (Nostoc paramelioides) colonies that house a midge symbiont (Cricotopus spp.), …

Stereocontrolled Access To Δ-Lactone-Fused-Γ-Lactams Bearing Angular Benzylic Quaternary Stereocenters, Timothy K. Beng, Morgan J. Rodriguez, Claire Borg

All Faculty Scholarship for the College of the Sciences

C-fused γ-lactam-lactones are resident in several bioactive molecules, including anticancer agents such as omuralide. In this embodiment, we report mild conditions for the catalytic halolactonization of lactam-tethered 5-aryl-4(E)-pentenoic acids. The use of dichloromethane as the solvent and Ph₃PS as the catalyst led to predominant 6-endo-trig cyclization and furnished the trans-fused-γ-lactam-δ-lactones. The transformation is modular, regioselective, chemoselective, and diastereoselective. The γ-lactam-δ-lactones bear angular quaternary benzylic stereocenters, which is noteworthy since the presence of a quaternary carbon in bioactive small molecules often promotes an element of conformational restriction that imparts potency, selectivity, and metabolic stability. The …

Sensitivity Of The West Antarctic Ice Sheet To +2 °C (Swais 2c), Molly O. Patterson, Richard H. Levy, Denise K. Kulhanek, Tina Van De Flierdt, Huw Horgan, Gavin B. Dunbar, Timothy R. Naish, Jeanine Ash, Alex Pyne, Darcy Mandeno, J. Paul Winberry

Geological Sciences Faculty Scholarship

The West Antarctic Ice Sheet (WAIS) presently holds enough ice to raise global sea level by 4.3 m if completely melted. The unknown response of the WAIS to future warming remains a significant challenge for numerical models in quantifying predictions of future sea level rise. Sea level rise is one of the clearest planet-wide signals of human-induced climate change. The Sensitivity of the West Antarctic Ice Sheet to a Warming of 2 ^∘C (SWAIS 2C) Project aims to understand past and current drivers and thresholds of WAIS dynamics to improve projections of the rate and size of ice sheet …

Black Carbon And Organic Carbon Dataset Over The Third Pole, Shichang Kang, Yulan Zhang, Pengfei Chen, Junming Guo, Qianggong Zhang, Zhiyuan Cong, Susan Kaspari, Lekhendra Tripathee, Tanguang Gao, Hewen Niu, Xinyue Zhong, Xintong Chen, Zhaofu Hu, Xiaofei Li, Yang Li, Bigyan Neupane, Fangping Yan, Dipesh Rupakheti, Chaman Gul, Wei Zhang, Guangming Wu, Ling Yang, Zhaoqing Wang, Chaoliu Li

Geological Sciences Faculty Scholarship

The Tibetan Plateau and its surroundings, also known as the Third Pole, play an important role in the global and regional climate and hydrological cycle. Carbonaceous aerosols (CAs), including black carbon (BC) and organic carbon (OC), can directly or indirectly absorb and scatter solar radiation and change the energy balance on the Earth. CAs, along with the other atmospheric pollutants (e.g., mercury), can be frequently transported over long distances into the inland Tibetan Plateau. During the last decades, a coordinated monitoring network and research program named “Atmospheric Pollution and Cryospheric Changes” (APCC) has been gradually set up and continuously operated …

Analysis Of Skills Sought By Employers Of Bachelors-Level Geoscientists, Gregory Shafer, Karen Viskuptic, Anne E. Egger

Geological Sciences Faculty Scholarship

Bachelors-level geoscientists make up the majority of the geoscience workforce, and positions for entry-level geoscientists are expected to grow rapidly over the next decade, with some jobs anticipating upward of 10% growth (National Center for O*NET Development, 2021). Are geoscience departments adequately preparing undergraduate students to succeed in these positions?

Design Of Broadband Helmholtz Resonator Arrays Using The Radiation Impedance Method, Vidhya Rajendran, Andy Piacsek, Tomás Méndez Echenagucia

All Faculty Scholarship for the College of the Sciences

This paper describes the design process of a low-frequency sound absorptive panel composed of differently tuned Helmholtz resonators (HRs), considering size and fabrication constraints relevant for applications in the building sector. The paper focuses on cylindrical and spiral resonators with embedded necks that are thin and can achieve high absorption. the mutual interaction between the resonators was modeled based on the radiation impedance method and it plays a key component in enhancing the absorption performance of the array. The differential evolution search algorithm was used to design the resonators and modify their mutual interaction to derive the absorption performance of …

Information Bottleneck In Deep Learning - A Semiotic Approach, Bogdan Musat, Razvan Andonie

Computer Science Faculty Scholarship

The information bottleneck principle was recently proposed as a theory meant to explain some of the training dynamics of deep neural architectures. Via information plane analysis, patterns start to emerge in this framework, where two phases can be distinguished: fitting and compression. We take a step further and study the behaviour of the spatial entropy characterizing the layers of convolutional neural networks (CNNs), in relation to the information bottleneck theory. We observe pattern formations which resemble the information bottleneck fitting and compression phases. From the perspective of semiotics, also known as the study of signs and sign-using behavior, the saliency …

Increased Caribbean Seismicity And Volcanism During Minima In Earth's Rotation Rate: Search For A Physical Mechanism And A 2030 Forecast, Roger Bilham, Walter Szeliga, David Mencin, Rebecca Bendick

Geological Sciences Faculty Scholarship

Three quarters of all Mw ≥ 6.6 earthquakes and volcanic eruptions surrounding the Caribbean plate occur preferentially during periods of decadal minima in Earth’s angular spin velocity. This correlation is revealed most clearly as a 4–6 years phase lag following the first derivative of the length of the day (LOD), Earth’s angular deceleration. We show that local strains and displacements resulting from oblateness changes, or plate boundary stresses associated with changes in tropical rotation rates are orders of magnitude lower than those typically associated with earthquake or volcano triggering. Notwithstanding the absence of a satisfactory causal physical mechanism, the relationship …