Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Faculty Publications

Discipline
Institution
Keyword
Publication Year
File Type

Articles 3721 - 3750 of 45717

Full-Text Articles in Entire DC Network

Chemical Communication In Insects: New Advances In Integrated Pest Management Strategies, Angel Guerrero, Gadi V.P. Reddy Oct 2023

Chemical Communication In Insects: New Advances In Integrated Pest Management Strategies, Angel Guerrero, Gadi V.P. Reddy

Faculty Publications

No abstract provided.


Early Season Monitoring Of Tarnished Plant Bug, Lygus Lineolaris, In Wild Hosts Using Pheromone Traps, Justin George, James P. Glover, Gadi V.P. Reddy, Chris Johnson, David R. Hall Oct 2023

Early Season Monitoring Of Tarnished Plant Bug, Lygus Lineolaris, In Wild Hosts Using Pheromone Traps, Justin George, James P. Glover, Gadi V.P. Reddy, Chris Johnson, David R. Hall

Faculty Publications

The tarnished plant bug, Lygus lineolaris (Hemiptera: Miridae), has a wide host range of over 700 plant species, including 130 crops of economic importance. During early spring, managing the field edges with weeds and other wild hosts is important in preventing early-season infestations of L. lineolaris in cotton to prevent damage to the squares and other fruiting structures. Scouting fields for L. lineolaris is time- and labor-intensive, and end-user variability associated with field sampling can lead to inaccuracies. Insect traps that combine visual cues and pheromones are more accurate, sustainable, and economically feasible in contrast to traditional insect detection methods. …


Can A Eutrophic Lake Function As A Carbon Sink? Case Study Of A Subtropical Eutrophic Lake In Southern Usa, Lee Potter, Y. J. Xu Oct 2023

Can A Eutrophic Lake Function As A Carbon Sink? Case Study Of A Subtropical Eutrophic Lake In Southern Usa, Lee Potter, Y. J. Xu

Faculty Publications

Carbon dioxide (CO2) outgassing from inland eutrophic waters is a small but critical component of the global carbon cycle that is currently not well constrained. Eutrophic lake systems have been reported to be supersaturated with dissolved CO2 (pCO2), therefore considered a carbon source to the atmosphere. In this study, we aimed to test two hypotheses: 1) there is a substantial diurnal fluctuation in pCO2 in eutrophic lakes, making them both a source and a sink of carbon; and 2) the diurnal fluctuation is seasonally dependent, with a pronounced variability during the summer. As a case study, we used a hypereutrophic …


Message Or Messenger? Source And Labeling Effects In Authoritarian Response To Protest, Daniel Arnon, Pearce Edwards, Handi Li Oct 2023

Message Or Messenger? Source And Labeling Effects In Authoritarian Response To Protest, Daniel Arnon, Pearce Edwards, Handi Li

Faculty Publications

Authoritarian regimes in the 21st century have increasingly turned to using information control rather than kinetic force to respond to threats to their rule. This paper studies an often overlooked type of information control: strategic labeling and public statements by regime sources in response to protests. Labeling protesters as violent criminals may increase support for repression by signaling that protests are illegitimate and deviant. Regime sources, compared to more independent sources, could increase support for repression even more when paired with such an accusatory label. Accommodative labels should have opposing effects—decreasing support for repression. The argument is tested with a …


Examination Of Real-Time Variation In Interpersonal Hopelessness And Suicidal Desire In A College Student Sample Reporting Past-2-Week Suicidal Ideation, Jessica L. Gerner, Emma H. Moscardini, Sean M. Mitchell, Ryan M. Hill, Raymond P. Tucker Oct 2023

Examination Of Real-Time Variation In Interpersonal Hopelessness And Suicidal Desire In A College Student Sample Reporting Past-2-Week Suicidal Ideation, Jessica L. Gerner, Emma H. Moscardini, Sean M. Mitchell, Ryan M. Hill, Raymond P. Tucker

Faculty Publications

Introduction: Interpersonal hopelessness (IH), as outlined in the Interpersonal Theory of Suicide, is theorized to include two correlated, distinct constructs: hopelessness about one's thwarted belongingness (IH-TB) and about perceived burdensomeness on others (IH-PB). Few studies have explored IH, and none have explored its temporal stability or prospective prediction of suicidal desire. Methods: Undergraduates (N = 43) selectively recruited for past-2-week suicidal ideation completed five ecological momentary assessment surveys per day for 10-days. Intraclass correlations, root mean square of successive differences, and multilevel models were used to examine the data and test relationships among predictor variables. Results: IH-TB and IH-PB demonstrated …


Relational Sanctification, Communal Coping, And Depression Among African American Couples, Antonius D. Skipper, Andrew H. Rose, Noel A. Card, Travis James Moore, Debra Lavender-Bratcher, Cassandra Chaney Oct 2023

Relational Sanctification, Communal Coping, And Depression Among African American Couples, Antonius D. Skipper, Andrew H. Rose, Noel A. Card, Travis James Moore, Debra Lavender-Bratcher, Cassandra Chaney

Faculty Publications

Despite the common use of religious buffers, African Americans are disproportionately affected by depressive symptoms. Communal coping may serve as one factor in helping religious African American couples alleviate the symptoms of depression. This study examines the association between relational sanctification and depressive symptoms as mediated by the communal coping of 467 African American married and cohabiting couples. Data from the sampled couples were analyzed using a common fate model, and analyses revealed higher scores on the measure of sanctification were associated with more communal coping; more communal coping was associated with fewer depressive symptoms among women and men, and …


Perceived Stress And Suicidal Ideation: The Role Of Dispositional Mindfulness, Emma H. Moscardini, Anthony Robinson, Jessica Gerner, Raymond P. Tucker Oct 2023

Perceived Stress And Suicidal Ideation: The Role Of Dispositional Mindfulness, Emma H. Moscardini, Anthony Robinson, Jessica Gerner, Raymond P. Tucker

Faculty Publications

Objectives: Extant literature suggests that dispositional mindfulness may reduce the impact perceived stress has on the severity of suicidal ideation (SI). Only one study has analyzed this question but did so with a cross-sectional design in a sample of undergraduate women. Methods: This study analyzed the potential moderating role of dispositional mindfulness on the relation between perceived stress and SI cross-sectionally and at one-week follow-up in a sample of US adults (N = 598) with a history of SI. Results: Results indicated that dispositional mindfulness and its facets were inversely related to perceived stress, SI severity at baseline, and SI …


Qtls And Candidate Loci Associated With Drought Tolerance Traits Of Kaybonnet X Zhe733 Recombinant Inbred Lines Rice Population, Yheni Dwiningsih, Julie Thomas, Anuj Kumar, Chirag Gupta, Navdeep Gill, Charles Ruiz, Jawaher Alkahtani, Niranjan Baisakh, Andy Pereira Oct 2023

Qtls And Candidate Loci Associated With Drought Tolerance Traits Of Kaybonnet X Zhe733 Recombinant Inbred Lines Rice Population, Yheni Dwiningsih, Julie Thomas, Anuj Kumar, Chirag Gupta, Navdeep Gill, Charles Ruiz, Jawaher Alkahtani, Niranjan Baisakh, Andy Pereira

Faculty Publications

Rice is the most important staple crop for the sustenance of the world’s population, and drought is a major factor limiting rice production. Quantitative trait locus (QTL) analysis of drought-resistance-related traits was conducted on a recombinant inbred line (RIL) population derived from the self-fed progeny of a cross between the drought-resistant tropical japonica U.S. adapted cultivar Kaybonnet and the drought-sensitive indica cultivar ZHE733. K/Z RIL population of 198 lines was screened in the field at Fayetteville (AR) for three consecutive years under controlled drought stress (DS) and well-watered (WW) treatment during the reproductive stage. The effects of DS were quantified …


Toward Food Security In 2050: Gene Pyramiding For Climate-Smart Rice, Isnaini Isnaini, Yudhistira Nugraha, Niranjan Baisakh, Nono Carsono Oct 2023

Toward Food Security In 2050: Gene Pyramiding For Climate-Smart Rice, Isnaini Isnaini, Yudhistira Nugraha, Niranjan Baisakh, Nono Carsono

Faculty Publications

The decline in crop productivity due to climate change is a major issue that threatens global food security and is the main challenge for breeders today in developing sustainable varieties with a wider tolerance to abiotic and biotic stresses. Breeding climate-smart rice (CSR) cultivars may be the best adaptation to climate change, with the potential to improve future food security and profitability for farmers in many nations. The main objective of this review is to highlight the direction of development of superior rice breeding from time to time, and various studies of new techniques of breeding methods for pyramiding various …


Reevaluation Of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin Equivalency Factors For Dioxin-Like Polychlorinated Dibenzo-P-Dioxins, Polychlorinated Dibenzofurans, And Polychlorinated Biphenyls For Fishes, Jon A. Doering, Donald E. Tillitt, Steve Wiseman Oct 2023

Reevaluation Of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin Equivalency Factors For Dioxin-Like Polychlorinated Dibenzo-P-Dioxins, Polychlorinated Dibenzofurans, And Polychlorinated Biphenyls For Fishes, Jon A. Doering, Donald E. Tillitt, Steve Wiseman

Faculty Publications

An expert meeting was organized by the World Health Organization (WHO) in 1997 to streamline assessments of risk posed by mixtures of dioxin-like chemicals (DLCs) through development of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) equivalency factors (TEFs) for mammals, birds, and fishes. No reevaluation has been performed for fish TEFs. Therefore, the objective of the present study was to reevaluate the TEFs for fishes based on an updated database of relative potencies (RePs) for DLCs. Selection criteria consistent with the WHO meeting resulted in 53 RePs across 14 species of fish ultimately being considered. Of these RePs, 70% were not available at the time …


Responses Of Phytoplankton Communities To Internal Waves In Oligotrophic Oceans, Lingqi Ma, Xiaolin Bai, Edward A. Laws, Wupeng Xiao, Cui Guo, Xin Liu, Kuo Ping Chiang, Kunshan Gao, Bangqin Huang Oct 2023

Responses Of Phytoplankton Communities To Internal Waves In Oligotrophic Oceans, Lingqi Ma, Xiaolin Bai, Edward A. Laws, Wupeng Xiao, Cui Guo, Xin Liu, Kuo Ping Chiang, Kunshan Gao, Bangqin Huang

Faculty Publications

Understanding the potential impacts of internal waves on phytoplankton communities in oligotrophic oceans remains an important research challenge. In this study, we elucidated the impact of internal waves on phytoplankton communities through a comprehensive 154-hr time-series of observations in the South China Sea (SCS). We identified distinctive variations in phytoplankton pigment biomass and composition across the upper, middle, and lower layers of the euphotic zone, which we attributed to the perturbations triggered by internal waves. Phytoplankton other than Prochlorococcus in the lower, nutrient-replete layer likely benefitted from allochthonous nutrients introduced by internal waves, but their growth rates were constrained by …


Multimessenger Diagnostics Of The Engine Behind Core-Collapse Supernovae, Christopher L. Fryer, Eric Burns, Aimee Hungerford, Samar Safi-Harb, R. T. Wollaeger, Richard S. Miller, Michela Negro, Samalka Anandagoda, Dieter H. Hartmann Oct 2023

Multimessenger Diagnostics Of The Engine Behind Core-Collapse Supernovae, Christopher L. Fryer, Eric Burns, Aimee Hungerford, Samar Safi-Harb, R. T. Wollaeger, Richard S. Miller, Michela Negro, Samalka Anandagoda, Dieter H. Hartmann

Faculty Publications

Core-collapse supernova explosions play a wide role in astrophysics by producing compact remnants (neutron stars or black holes) and the synthesis and injection of many heavy elements into their host galaxy. Because they are produced in some of the most extreme conditions in the universe, they can also probe physics in extreme conditions (matter at nuclear densities and extreme temperatures and magnetic fields). To quantify the impact of supernovae on both fundamental physics and our understanding of the universe, we must leverage a broad set of observables of this engine. In this paper, we study a subset of these probes …


Deep Multimessenger Search For Compact Binary Mergers In Ligo, Virgo, And Fermi/Gbm Data From 2016-2017, Marion Pillas, Tito Dal Canton, Cosmin Stachie, Brandon Piotrzkowski, Fergus Hayes, Rachel Hamburg, Eric Burns, Joshua Wood, Pierre Alexandre Duverne, Nelson Christensen Oct 2023

Deep Multimessenger Search For Compact Binary Mergers In Ligo, Virgo, And Fermi/Gbm Data From 2016-2017, Marion Pillas, Tito Dal Canton, Cosmin Stachie, Brandon Piotrzkowski, Fergus Hayes, Rachel Hamburg, Eric Burns, Joshua Wood, Pierre Alexandre Duverne, Nelson Christensen

Faculty Publications

GW170817-GRB 170817A provided the first observation of gravitational waves from a neutron star merger with associated transient counterparts across the entire electromagnetic spectrum. This discovery demonstrated the long-hypothesized association between short gamma-ray bursts and neutron star mergers. More joint detections are needed to explore the relation between the parameters inferred from the gravitational wave and the properties of the gamma-ray burst signal. We developed a joint multimessenger analysis of LIGO, Virgo, and Fermi/GBM data designed for detecting weak gravitational-wave transients associated with weak gamma-ray bursts. As such, it does not start from confident (GWTC-1) events only. Instead, we take the …


Engineering Super-Poissonian Photon Statistics Of Spatial Light Modes, Mingyuan Hong, Ashe Miller, Roberto De J. León-Montiel, Chenglong You, Omar S. Magaña-Loaiza Oct 2023

Engineering Super-Poissonian Photon Statistics Of Spatial Light Modes, Mingyuan Hong, Ashe Miller, Roberto De J. León-Montiel, Chenglong You, Omar S. Magaña-Loaiza

Faculty Publications

The nature of light sources is defined by the statistical fluctuations of the electromagnetic field. As such, the photon statistics of light sources are typically associated with distinct emitters. Here, the possibility of producing light beams with various photon statistics through the spatial modulation of coherent light is demonstrated. This is achieved by the sequential encoding of controllable Kolmogorov phase screens in a digital micromirror device. Interestingly, the flexibility of this scheme allows for the shaping of spatial light modes with engineered photon statistics at different spatial positions. The performance of this scheme is assessed through the photon-number-resolving characterization of …


Kmt-2021-Blg-1547lb: Giant Microlensing Planet Detected Through A Signal Deformed Due To Source Binarity, Cheongho Han, Weicheng Zang, Youn Kil Jung, Ian A. Bond, Sun Ju Chung, Michael D. Albrow, Andrew Gould, Kyu Ha Hwang, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Hongjing Yang, Jennifer C. Yee, Sang Mok Cha, Doeon Kim, Dong Jin Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, Berto Monard, Qiyue Qian, Zhuokai Liu, Dan Maoz, Matthew T. Penny, Wei Zhu, Fumio Abe, Richard Barry, David P. Bennett, Aparna Bhattacharya, Hirosame Fujii Oct 2023

Kmt-2021-Blg-1547lb: Giant Microlensing Planet Detected Through A Signal Deformed Due To Source Binarity, Cheongho Han, Weicheng Zang, Youn Kil Jung, Ian A. Bond, Sun Ju Chung, Michael D. Albrow, Andrew Gould, Kyu Ha Hwang, Yoon Hyun Ryu, In Gu Shin, Yossi Shvartzvald, Hongjing Yang, Jennifer C. Yee, Sang Mok Cha, Doeon Kim, Dong Jin Kim, Seung Lee Kim, Chung Uk Lee, Dong Joo Lee, Yongseok Lee, Byeong Gon Park, Richard W. Pogge, Berto Monard, Qiyue Qian, Zhuokai Liu, Dan Maoz, Matthew T. Penny, Wei Zhu, Fumio Abe, Richard Barry, David P. Bennett, Aparna Bhattacharya, Hirosame Fujii

Faculty Publications

Aims. We investigate the previous microlensing data collected by the KMTNet survey in search of anomalous events for which no precise interpretations of the anomalies had been suggested. From this investigation, we find that the anomaly in the lensing light curve of the event KMT-2021-BLG-1547 is approximately described by a binary-lens (2L1S) model with a lens possessing a giant planet, but the model leaves unexplained residuals. Methods. We investigated the origin of the residuals by testing more sophisticated models that include either an extra lens component (3L1S model) or an extra source star (2L2S model) on top of the 2L1S …


Does Investment In Green Employee Development Climate Matter For Environmental Commitment And Green Well-Being? A Case Study Of A Palm Oil Company In Malaysia, Patricia Yinyin Lau, Sunyoung Park, Yen Chen Hsu, Bella Ya Hui Lien, Jo Ann Ho Oct 2023

Does Investment In Green Employee Development Climate Matter For Environmental Commitment And Green Well-Being? A Case Study Of A Palm Oil Company In Malaysia, Patricia Yinyin Lau, Sunyoung Park, Yen Chen Hsu, Bella Ya Hui Lien, Jo Ann Ho

Faculty Publications

Drawing on social exchange theory and stakeholder responses to corporate social responsibility model, this study aimed to examine if the cross-level impacts of perceived investment in green employee development climate (PIGED) on environmental commitment (EC) and green well-being (GWB) were mediated by green person-job fit and green growth need strength. We collected a total of 412 employees and 80 operating units from a leading palm-oil company in Malaysia. The multilevel regression analysis found the cross-level effects of PIGED on EC and GWB that were partially mediated by green person-job fit and green growth need strength. Due to incomplete understanding of …


Sexually Dimorphic Oxytocin Receptor-Expressing (Oxtr) Neurons In The Anteroventral Periventricular Nucleus (Avpv) In The Postpartum Female Mouse Are Involved In Maternal Behavior, Kaustubh Sharma, Armita A. Govar, Bandana Ghimire, Katsuhiko Nishimori, Elizabeth Hammock, Ryoichi Teruyama Oct 2023

Sexually Dimorphic Oxytocin Receptor-Expressing (Oxtr) Neurons In The Anteroventral Periventricular Nucleus (Avpv) In The Postpartum Female Mouse Are Involved In Maternal Behavior, Kaustubh Sharma, Armita A. Govar, Bandana Ghimire, Katsuhiko Nishimori, Elizabeth Hammock, Ryoichi Teruyama

Faculty Publications

Maternal care is crucial for the survival and development of offspring. Oxytocin modulates maternal behavior by binding to oxytocin receptors (OXTRs) in various parts of the brain. Previously, we showed that OXTRs are expressed in the anteroventral periventricular nucleus (AVPV) of female, but not male mice. Because the AVPV is involved in the regulation of maternal behavior and oxytocin enhances its induction, this finding leads to the hypothesis that the female specific population of OXTR neurons in the AVPV regulates maternal behavior. To address this hypothesis, OXTR-Venus reporter mice were used to assess if expression levels of OXTR in the …


Pubertal Progression And Its Relationship To Psychological And Behavioral Outcomes Among Adolescent Boys, Meng-Che Tsai, Yu-Chung Lawrence Wang, Hsun-Yu Chan Oct 2023

Pubertal Progression And Its Relationship To Psychological And Behavioral Outcomes Among Adolescent Boys, Meng-Che Tsai, Yu-Chung Lawrence Wang, Hsun-Yu Chan

Faculty Publications

Variations in pubertal timing and tempo have relevance to psychosocial development. Accounting for pubertal timing, tempo, and psychosocial development simultaneously in a model remains challenging. This study aimed to document the typology of pubertal development in a cohort of Taiwanese adolescent boys and then to examine how the associations between psychosocial variables across time vary by the patterns of pubertal development. A group of adolescent boys (n = 1,368) reported pubertal signs and psychosocial variables for 3 years since seventh grade. The growth mixture model revealed three major classes of pubertal transition: average pubertal growth, late-onset with rapid catch-up, and …


Strategies Elementary School Children Use To Influence Mothers' Food Purchasing Decisions, Nazratun N. Monalisa, Edward A. Frongillo Ph.D., Christine E. Blake Ph.D., Rd, Susan E. Steck, Robin B. Dipietro Oct 2023

Strategies Elementary School Children Use To Influence Mothers' Food Purchasing Decisions, Nazratun N. Monalisa, Edward A. Frongillo Ph.D., Christine E. Blake Ph.D., Rd, Susan E. Steck, Robin B. Dipietro

Faculty Publications

This study aimed to understand the strategies elementary-school-aged children used to influence mothers' food purchasing decisions. Semi-structured qualitative interviews were conducted with 40 children aged 6–11 years and their mothers living in South Carolina. Strategies to influence mothers' food purchases were collected from children and their mothers separately. The interviews were audio-recorded, transcribed verbatim, and open-coded. The constant comparative method was used for data analysis. Coding matrices were used to compare children's and mothers' responses on the children's strategies. Children reported 157 instances of 25 distinct strategies to influence mothers' purchasing decisions. Mothers had concordance with 83 instances of these …


Spatial And Wavelet Analysis Of Precipitation And River Discharge During Operation Of The Three Gorges Dam, China, Lirong Yin, Lei Wang, Barry D. Keim, Kory Konsoer, Zhengtong Yin, Mingzhe Liu, Wenfeng Zheng Oct 2023

Spatial And Wavelet Analysis Of Precipitation And River Discharge During Operation Of The Three Gorges Dam, China, Lirong Yin, Lei Wang, Barry D. Keim, Kory Konsoer, Zhengtong Yin, Mingzhe Liu, Wenfeng Zheng

Faculty Publications

The Three Gorges Dam and Reservoir on the Yangtze River is one of the world's largest dams. After the dam's construction in 1997, the reservoir started filling up, expanding to a size of over 600 km2. Therefore, its possible influence on maintaining the size and water level of this waterbody is significant and concerning. This research utilized wavelet coherence analysis to examine the temporal correlation and phase coherence among various datasets, including dam injection (1998–2018) and discharge (2003–2018) data, ground station precipitation data along the Yangtze River (1998–2020), and river discharge raster maps 1998–2018. The analysis revealed a strong coherence …


Loss Aversion In The Control Of Attention, Sunghyun Kim, Melissa R. Beck, Yang Seok Cho Oct 2023

Loss Aversion In The Control Of Attention, Sunghyun Kim, Melissa R. Beck, Yang Seok Cho

Faculty Publications

Loss aversion is a psychological bias where an increase in loss is perceived as being larger than an equivalent increase in gain. In the present study, two experiments were conducted to explore whether attentional control reflects loss aversion. Participants performed a visual search task. On each trial, a red target and a green target were presented simultaneously, and participants were free to search for either one. Participants always gained points when they searched for a gain color target (e.g., red). However, they gained or lost points when they searched for a gain-loss color target (e.g., green). In Experiment 1, the …


Deficiency Of Healthcare Accessibility Of Elderly People Exposed To Future Extreme Coastal Floods: A Case Study Of Shanghai, China, Xinmeng Shan, Paolo Scussolini, Jun Wang, Mengya Li, Jiahong Wen, Lei Wang Oct 2023

Deficiency Of Healthcare Accessibility Of Elderly People Exposed To Future Extreme Coastal Floods: A Case Study Of Shanghai, China, Xinmeng Shan, Paolo Scussolini, Jun Wang, Mengya Li, Jiahong Wen, Lei Wang

Faculty Publications

Socioeconomic development, subsidence, and climate change have led to high flood risks in coastal cities, making the vulnerable, especially elderly people, more prone to floods. However, we mostly do not know how the accessibility of life-saving public resources for the elderly population will change under future scenarios. Using Shanghai as a case, this study introduced a new analytical framework to fill this gap. We integrated for the first time models of coastal flooding, local population growth, and medical resource supply-demand estimation. The results show that under an extreme scenario of coastal flooding in the year 2050, in the absence of …


U-Net-Lstm: Time Series-Enhanced Lake Boundary Prediction Model, Lirong Yin, Lei Wang, Tingqiao Li, Siyu Lu, Jiawei Tian, Zhengtong Yin, Xiaolu Li, Wenfeng Zheng Oct 2023

U-Net-Lstm: Time Series-Enhanced Lake Boundary Prediction Model, Lirong Yin, Lei Wang, Tingqiao Li, Siyu Lu, Jiawei Tian, Zhengtong Yin, Xiaolu Li, Wenfeng Zheng

Faculty Publications

Change detection of natural lake boundaries is one of the important tasks in remote sensing image interpretation. In an ordinary fully connected network, or CNN, the signal of neurons in each layer can only be propagated to the upper layer, and the processing of samples is independent at each moment. However, for time-series data with transferability, the learned change information needs to be recorded and utilized. To solve the above problems, we propose a lake boundary change prediction model combining U-Net and LSTM. The ensemble of LSTMs helps to improve the overall accuracy and robustness of the model by capturing …


Coir/Glass Hybrid Fiber Reinforced Thermoset Polymer Composite Laminates With Room-Temperature Self-Healing And Shape Memory Functions, Sakil Mahmud, John Konlan, Jenny Deicaza, Guoqiang Li Oct 2023

Coir/Glass Hybrid Fiber Reinforced Thermoset Polymer Composite Laminates With Room-Temperature Self-Healing And Shape Memory Functions, Sakil Mahmud, John Konlan, Jenny Deicaza, Guoqiang Li

Faculty Publications

Natural fibers have a lot of potentials as renewable reinforcements for polymers. However, their lower load-carrying capacity compared with synthetic fibers made it a challenge to use them as polymer reinforcements. When a laminated composite beam is bent, the normal stress is the highest on the top and bottom layers and zero in the midplane due to the (non)linear distribution of normal strain. Even though the shear stress is the highest in the midplane, most polymers can tolerate the high shear stress. Therefore, hybrid composite laminates with strong synthetic glass fibers stacked over the core of weak natural coir fiber …


Machine-Learning-Based Thermal Conductivity Prediction For Additively Manufactured Alloys, Uttam Bhandari, Yehong Chen, Huan Ding, Congyuan Zeng, Selami Emanet, Paul R. Gradl, Shengmin Guo Oct 2023

Machine-Learning-Based Thermal Conductivity Prediction For Additively Manufactured Alloys, Uttam Bhandari, Yehong Chen, Huan Ding, Congyuan Zeng, Selami Emanet, Paul R. Gradl, Shengmin Guo

Faculty Publications

Thermal conductivity (TC) is greatly influenced by the working temperature, microstructures, thermal processing (heat treatment) history and the composition of alloys. Due to computational costs and lengthy experimental procedures, obtaining the thermal conductivity for novel alloys, particularly parts made with additive manufacturing, is difficult and it is almost impossible to optimize the compositional space for an absolute targeted value of thermal conductivity. To address these difficulties, a machine learning method is explored to predict the TC of additive manufactured alloys. To accomplish this, an extensive thermal conductivity dataset for additively manufactured alloys was generated for several AM alloy families (nickel, …


Additive Friction Stir Deposition Of Metallic Materials: Process, Structure And Properties, Jiayun Shao, Arash Samaei, Tianju Xue, Xiaoyu Xie, Shengmin Guo, Jian Cao, Eric Macdonald, Zhengtao Gan Oct 2023

Additive Friction Stir Deposition Of Metallic Materials: Process, Structure And Properties, Jiayun Shao, Arash Samaei, Tianju Xue, Xiaoyu Xie, Shengmin Guo, Jian Cao, Eric Macdonald, Zhengtao Gan

Faculty Publications

Additive friction stir deposition (AFSD) is a relatively new additive manufacturing technique to fabricate parts in solid state below the melting temperature. Due to the solid-state nature, AFSD benefits from lower residual stresses as well as significantly lower susceptibility to porosity, hot-cracking, and other defects compared to conventional fusion-based metallic additive manufacturing. These unique features make AFSD a promising alternative to conventional forging for fabricating large structures for aerospace, naval, nuclear, and automotive applications. This review comprehensively summarizes the advances in AFSD, as well as the microstructure and properties of the final part. Given the rapidly growing research in AFSD, …


The Standard For Assessing Water Resistance Properties Of Lubricating Grease Using Contact Angle Measurements, Koottaparambil Lijesh, Roger A. Miller, Raj Shah, Khosro Shirvani, Michael M. Khonsari Oct 2023

The Standard For Assessing Water Resistance Properties Of Lubricating Grease Using Contact Angle Measurements, Koottaparambil Lijesh, Roger A. Miller, Raj Shah, Khosro Shirvani, Michael M. Khonsari

Faculty Publications

Many grease-lubricated machines operate in wet environments, and are vulnerable to contamination because of water exposure. Reports suggest that even the presence of 1% water in grease reduces the life of a bearing by 90%. Nevertheless, only a few qualitative tests and standards are available to characterize the water resistance properties of greases. In this paper, we propose a standard for evaluating the water resistance properties of greases by studying their hydrophobic and hydrophilic nature via a custom-designed apparatus for measuring the grease contact angle. In this approach, a water droplet is dispensed onto the surface of the grease and …


In Situ Prediction Of Metal Fatigue Life Using Frequency Change, Ali Mahmoudi, Mohammad A. Amooie, Lijesh Koottaparambil, Michael M. Khonsari Oct 2023

In Situ Prediction Of Metal Fatigue Life Using Frequency Change, Ali Mahmoudi, Mohammad A. Amooie, Lijesh Koottaparambil, Michael M. Khonsari

Faculty Publications

A reliable technique for rapid prediction of the remaining useful life (RUL) of components experiencing fatigue degradation is introduced. The approach is based on measuring the temperature signature of a component upon rapidly changing its operating frequency for a short period of time. The temperature variations caused by alterations in plastic work rate are correlated to the loading history. The efficacy of the approach is investigated by conducting a series of axial fatigue tests on stainless steel 316 specimens. The material characterization involves subjecting the material to a constant amplitude fatigue load at 4 Hz and 12 Hz frequencies. The …


Comparative Analyses Of Covariance Matrix Adaptation And Iterative Ensemble Smoother On High-Dimensional Inverse Problems In High-Resolution Groundwater Modeling, Shuo Yang, Frank T.C. Tsai, Peter Bacopoulos, Christopher E. Kees Oct 2023

Comparative Analyses Of Covariance Matrix Adaptation And Iterative Ensemble Smoother On High-Dimensional Inverse Problems In High-Resolution Groundwater Modeling, Shuo Yang, Frank T.C. Tsai, Peter Bacopoulos, Christopher E. Kees

Faculty Publications

Parameter estimation is an inverse problem which is crucial to reliable groundwater model predictions and management. Numerous techniques have been developed to address this challenging problem. This study aims to compare the performance of a stochastic optimization method, covariance matrix adaptation-evolution strategy (CMA-ES), and a data assimilation method, Levenberg-Marquardt based iterative ensemble smoother (ES-LM), on solving inverse problems in groundwater modeling. This study also presents a parallelization strategy to accelerate their implementation. The comparative analysis involves synthetic inverse problems and a real-world case study of calibrating a high-resolution groundwater model. Results from the synthetic problems suggest that both the CMA-ES …


Coupled Wellbore-Reservoir Modelling To Evaluate Co2 Injection Rate Distribution Over Thick Multilayer Storage Zones, Mohamed Abdelaal, Mehdi Zeidouni Oct 2023

Coupled Wellbore-Reservoir Modelling To Evaluate Co2 Injection Rate Distribution Over Thick Multilayer Storage Zones, Mohamed Abdelaal, Mehdi Zeidouni

Faculty Publications

Technical and economic feasibility of Geologic CO2 Storage (GCS) projects requires maximizing the amount of stored CO2 per unit pore space of the storage zone per well. Considering injection through a fully penetrating vertical well in a multi-layer thick aquifer, CO2 would be unevenly distributed over the aquifer thickness, underutilizing the available pore space. In this work, we use coupled wellbore-reservoir modelling to investigate the interplay between the parameters that control CO2 pore-space filling. Flow capacity profile and gravity/buoyancy override are the primary factors controlling CO2 flux into a layered system. In addition, a higher fraction of CO2 would flow …