Physical Sciences and Mathematics Commons^™

Quality Seed Production Of Range Grasses--A Major Constraint In Revitalising Tropical Pastures, D. R. Malaviya, D. Vijay, Chandan Kumar Gupta, Ajoy K. Roy, P. Kaushal

IGC Proceedings (1977-2023)

Only 4% of India’s geographical area of 326.82 M ha is under pastures. Socioeconomic and ecological consequ-ences of land degradation are affecting 85 M ha of rangelands/grasslands. To provide sufficient milk for the ever-growing population, current milk production of 128 M t must increase to 160 M t by 2020. To make this possible, an additional 825 M t of green fodder is required. Increasing the area producing green fodder is difficult because of severe competition from food crops. Revitalising the denuded grasslands is the most plausible means for improving the availability of green fodder. This needs mission mode programs …

Status Of Animal Feed Resources In Rwanda, M. Mutimura, A. B. Lussa, J. Mutabazi, C. B. Myambi, R. A. Cyamweshi, C. Ebong

IGC Proceedings (1977-2023)

Animal feed resources remain a major constraint for livestock development in tropical Africa. In Rwanda, grazing lands are shrinking sharply because crop cultivation is progressively encroaching on grazing areas with increasing human pressure (Mutimura and Everson 2011). Therefore, over 60% of households cultivating less than 0.7 ha, and owning livestock, practise zero-grazing, where farmers cut-and-carry forage and crop residues to feed animals that are kept exclusively under sheds (MINAGRI 2009). In general, the main feed for dairy cattle under a zero-grazing system is Napier grass (Pennisetum purpureum). For more than a decade, efforts to improve the feed resource …

Effect Of Cutting Interval On Yield And Quality Of Two Panicum Maximum Cultivars In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1977-2023)

Tanzania guinea grass [Panicum maximum cv. Tanzania (cv. Purple in Thailand)] has been grown in Thailand for over 20 years and has proven to be a high quality forage (Phaikaew et al. 2007). Mombasa guinea grass (Panicum maximum cv. Mombasa) was introduced to Thailand in 2007 and commercial seed production commenced in 2008 because of a demand for seed in central and South America (Hare et al. 2013). It is a larger and taller cultivar than Tanzania. A series of studies have been undertaken at Ubon Ratchathani University, Thailand, to study the agronomic differences between these …

Effect Of Cutting Interval On Yield And Quality Of Three Brachiaria Hybrids In Thailand, Michael D. Hare, Supaphan Phengphet, Theerachai Songsiri, Naddakorn Sutin, Eduardo Stern

IGC Proceedings (1977-2023)

In field trials in Thailand, Brachiaria hybrid cv. Mulato II produced significantly more green leaf, particularly during the dry season, than other brachiaria grasses (Hare et al. 2009). Cultivar Cayman produced more dry matter (DM) than Mulato II in one out of 3 wet seasons, and line BRO2/1794 produced similar DM yields to Mulato II (Pi-zarro et al. 2013).

The objective of this field study was to determine the effects of varying cutting intervals on growth and forage quality of hybrid brachiaria grasses in Thailand on infertile soils.

Brachiaria Hybrids: Potential, Forage Use And Seed Yield, Esteban A. Pizarro, Michael D. Hare, Mpenzi Mutimura, Changjun Bai

IGC Proceedings (1977-2023)

A brachiaria breeding program initiated in 1988 at CIAT (Centro Internacional de Agricultura Tropical) combined desirable attributes found in accessions of Brachiaria brizantha and B. decumbens. Three apomictic hybrids have been released (cvs. Mulato, Mulato II and Cayman). Mulato showed agronomic potential but seed yields were low. Trials in Central America demonstrated the superiority of Mulato II, a vigorous grass with very deep and branched roots, giving it excellent drought resistance in the Brazilian Cerrado and Mexico. Mulato II has excellent nutritional value. Following trials in Mexico and Thailand, evaluating 155 new hybrids for 7 years, cv. Cayman was …

Molecular Genetic Variability, Population Structure And Mating System In Tropical Forages, Melissa Garcia, Bianca B. Z. Vigna, Adna C. B. Sousa, Letícia Jungmann, Fernanda W. Cidade, Guilherme Toledo-Silva, Patricia M. Francisco, Lucimara Chiari, Marcelo A. Carvalho, Claudio T. Karia, Fabio G. Faleiro, Rodolfo Godoy, M. Dall’Agnol, Sueli S. Pagliarini, Francisco H. D. Souza, Tatiana T. Souza-Chies, Liana Jank, Rosangela M. S. Resende, Cacilda B. Valle, Maria I. Zucchi, Anete P. Souza

IGC Proceedings (1977-2023)

Microsatellite (SSR) markers were developed for the following tropical forage species, using accessions available from the plant genetic resources (PGR) collections held by EMBRAPA (Brazilian Agricultural Research Corporation): Brachiaria brizantha, B. humidicola, Panicum maximum, Paspalum spp., Stylosanthes capitata, S. guianensis, S. macrocephala, Calopogonium mucunoides and Centrosema spp. The markers were used to analyse population structure and genetic diversity, evolution and origin of the genetic variability in the centre of origin, mating systems and genetic resources in EMBRAPA’s germplasm bank. The results shed light on the amount of genetic variation within and between populations, revealed …

Leucaena Toxicity: A New Perspective On The Most Widely Used Forage Tree Legume, Michael J. Halliday, Jagadish Padmanabha, Chris S. Mcsweeney, Graham L. Kerven, H. Max Shelton

IGC Proceedings (1977-2023)

The tree legume Leucaena leucocephala (leucaena) is a high quality ruminant feed, vitally important for livestock production in the tropics despite the presence of mimosine in the leaves. This toxic non-protein amino acid has the potential to limit productivity and adversely affect the health of animals. The discovery and subsequent distribution in Australia of the ruminal bacterium Synergistes jonesii as an oral inoculum was shown in the 1980s to overcome these toxic effects. However, recent surveys of the status of toxicity worldwide; improved understanding of the chemistry and mode of action of the toxins; new techniques for molecular sequencing; and …

Efficient Smooth Non-Convex Stochastic Compositional Optimization Via Stochastic Recursive Gradient Descent, Wenqing Hu, Chris Junchi Li, Xiangru Lian, Ji Liu, Huizhuo Yuan

Mathematics and Statistics Faculty Research & Creative Works

Stochastic compositional optimization arises in many important machine learning applications. The objective function is the composition of two expectations of stochastic functions, and is more challenging to optimize than vanilla stochastic optimization problems. In this paper, we investigate the stochastic compositional optimization in the general smooth non-convex setting. We employ a recently developed idea of Stochastic Recursive Gradient Descent to design a novel algorithm named SARAH-Compositional, and prove a sharp Incremental First-order Oracle (IFO) complexity upper bound for stochastic compositional optimization: 𝒪((n + m)^1/2ε^-2) in the finite-sum case and 𝒪(ε^-3) in the online case. …

A Pedagogic Analysis Of Linear Algebra Courses, Andrew Taylor

Mathematics & Statistics ETDs

This project is concerned with investigating the question, "Do our applied linear algebra courses (at the University of New Mexico) adequately prepare STEM students for future work in their respective fields?" In order to explore this, surveys were issued to three groups (sections) of students (among two different instructors) at the conclusion of their applied linear algebra course, as well as STEM professors/instructors from a variety of STEM fields. Students were surveyed regarding their perceived mastery of given topics/ideas from the course and professors/instructors were surveyed about the level of mastery they felt was necessary (referred to as ``desired mastery") …

Direct Observation Of Atomic Exchange During Surface Self-Diffusion, Matthew Aaron Koppa

Physics & Astronomy ETDs

The diffusion of adatoms across the (100) plane of iridium has been previously inferred to occur by an exchange mechanism based on site mapping. This study provides the first direct observation that surface self-diffusion can occur by exchange. Iridium enriched to ≥93% ¹⁹¹Ir was deposited onto an atomically clean and smooth Ir(100) plane as observed in an atom probe field ion microscope. Following thermally activated surface self-diffusion the adatom was field desorbed and mass analyzed. Observation of the ¹⁹³Ir isotope in one-half of the cases demonstrates conclusively that atomic exchange can occur during surface self-diffusion.

How To Promote Education For Sustainable Development? Vision Of The Educational Situation And Its Contribution To Sustainable Development., Khalid Aada

Writing and Language Studies Faculty Publications

During the last decade, the importance of leaving a rational paradigm, debtor of functionalist and utilitarian models, towards another more congruent with the preservation of natural resources, and therefore of life, has been widely discussed. In the same way, different voices have been raised, pointing out the urgency of inserting these precepts into the educational field, hoping to achieve the true cultural transformation that is needed to consolidate the change. Multiple International Entities promote sustainability in Education as an initiative that should be ambitious, complex and reforming character, given the global scope of the social, economic and environmental situation affecting …

Computational Screening Of New Perovskite Materials Using Transfer Learning And Deep Learning, Xiang Li, Yabo Dan, Rongzhi Dong, Zhuo Cao, Chengcheng Niu, Yuqi Song, Shaobo Li, Jianjun Hu

Faculty Publications

As one of the most studied materials, perovskites exhibit a wealth of superior properties that lead to diverse applications. Computational prediction of novel stable perovskite structures has big potential in the discovery of new materials for solar panels, superconductors, thermal electric, and catalytic materials, etc. By addressing one of the key obstacles of machine learning based materials discovery, the lack of sufficient training data, this paper proposes a transfer learning based approach that exploits the high accuracy of the machine learning model trained with physics-informed structural and elemental descriptors. This gradient boosting regressor model (the transfer learning model) allows us …

Learning Nearest Neighbor Graphs From Noisy Distance Samples, Blake Mason, Ardhendu S. Tripathy, Robert Nowak

Computer Science Faculty Research & Creative Works

We consider the problem of learning the nearest neighbor graph of a dataset of n items. The metric is unknown, but we can query an oracle to obtain a noisy estimate of the distance between any pair of items. This framework applies to problem domains where one wants to learn people's preferences from responses commonly modeled as noisy distance judgments. In this paper, we propose an active algorithm to find the graph with high probability and analyze its query complexity. In contrast to existing work that forces Euclidean structure, our method is valid for general metrics, assuming only symmetry and …

Maxgap Bandit: Adaptive Algorithms For Approximate Ranking, Sumeet Katariya, Ardhendu S. Tripathy, Robert Nowak

Computer Science Faculty Research & Creative Works

This paper studies the problem of adaptively sampling from K distributions (arms) in order to identify the largest gap between any two adjacent means. We call this the MaxGap-bandit problem. This problem arises naturally in approximate ranking, noisy sorting, outlier detection, and top-arm identification in bandits. The key novelty of the MaxGap bandit problem is that it aims to adaptively determine the natural partitioning of the distributions into a subset with larger means and a subset with smaller means, where the split is determined by the largest gap rather than a pre-specified rank or threshold. Estimating an arm's gap requires …

Normalized Multi-Bump Solutions For Saturable Schrödinger Equations, Xiaoming Wang, Zhi-Qiang Wang

Mathematics and Statistics Faculty Publications

In this paper, we are concerned with the existence of multi-bump solutions for a class of semiclassical saturable Schrödinger equations with an density function:

We prove that, with the density function being radially symmetric, for given integer k ≥ 2 there exist a family of non-radial, k-bump type normalized solutions (i.e., with the L² constraint) which concentrate at the global maximum points of density functions when ε → 0⁺. The proof is based on a variational method in particular on a convexity technique and the concentration-compactness method.

Influence Of Biosolids Upon The Uptake Of Mn And Cd By Radish (Raphanus Sativus L.), Oluwadamilola O. Fateru

Electronic Theses and Dissertations

The influence of biosolids upon the uptake of Mn and Cd by radish (Raphanus sativus L.) was investigated through the characterization of biosolids, sequential extraction of the biosolids, and the determination of the metal content in the root, shoot and leaves of radish (Raphanus sativus L.).The biosolid samples from Nacogdoches Wastewater Sludge (NWWS), Lufkin Wastewater Sludge (LWWS), Soil Therapy Compost (STC) had pHs between 5.33 – 6.74. The elemental compositions of the biosolid samples were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES) and SEM/EDX. Major elements (K, Mg, Mn, P) needed for plant growth …

The Firece Green Fire: Vol. 10 Issue 13, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Vintage Report 2019: North Willamette Valley, Gregory V. Jones

Linfield University Wine Studies Reports

This report describes the impacts of climate and phenology on vintage for the North Willamette Valley in Oregon in 2019. A relatively mild early winter in 2018 was followed by a cold and wet second half of winter in 2019 and then a wet, but warm, spring. The growing season saw a few mild frosts during late April, but started off warmer than average, moderating through mid-vintage with fewer than average heat spikes. Near-record precipitation amounts during late June and early July brought increased disease pressure to the region. The vintage will be remembered for the early rains in September …

Design Of Efgr Kinase Domain Inhibitors For The Potential Treatment Of Lung And Other Cancers, Jodie Meng '20

Student Publications & Research

In 2018 alone, over 18 million cancer-related cases were diagnosed and 9.5 million cancer-related deaths occurred worldwide. As a small-molecule drug orally administered for the treatment of lung and pancreatic cancer, erlotinib (Tarceva®) inhibits the phosphorylation of the tyrosine kinase domain in the Epidermal Growth Factor Receptor (EGFR). Inhibition of EGFR reduces the bioactivity of tumor-associated endothelial cells and interferes with signal pathways involved in metastasis and development of angiogenesis. Increase in drug concentration leads to adverse effects, ranging from rash and nausea to gastrointestinal bleeding, perforation, hepatic failure, among others. Therefore, it is desirable to reduce the toxicity and …

Computer-Aided Drug Design For The Potential Treatment Against Mycobacterium Tuberculosis, Alyssa Daniels '20, Rebecca Ellington '19

Student Publications & Research

Tuberculosis (TB) is a disease that can infect any part of the body, but most often infects the lungs. About 9 million people are infected with TB each year, and left untreated, TB is deadly. However, even when treated, Mycobacterium Tuberculosis (MTB), the pathogenic bacteria responsible for TB, can become drug-resistant and patients will need a much more rigorous treatment. Isocitrate lyase (ICL) is an enzyme that allows tuberculosis (and other pathogens) to survive in the body. ICL is an enzyme in the glyoxylate cycle that catalyzes the cleavage of isocitrate to succinate and glyoxylate. MTB is facilitated by this …

Research On Simulation Platform For Equipment System Analysis, Yuping Li, Shaojie Mao, Zhenqi Ju, Zhou Fang, Guoqiang Yan

Journal of System Simulation

Abstract: With the development of equipment construction from platform-centric to network-centric, simulation analysis of equipment system is an important means and tool to support the transformation and development of equipment construction under the condition of multi-task joint operation. Starting from the requirement of system simulation analysis, a cloud-based equipment system simulation architecture is proposed to realize flexible and configurable simulation environment according to task requirements; and a high-performance simulation framework is conducted, which provides strong support for different application modes, such as parallel hyper-real-time and distributed simulation deduction. The unified description, organization and management method of model and data resources …

Parallel Tasks Optimization Scheduling In Cloud Manufacturing System, Chenwei Feng, Wang Yan

Journal of System Simulation

Abstract: To solve the problem of unbalanced resource requirements and low resource utilization when the same type of tasks are executed in parallel in the cloud manufacturing system, a task resource scheduling model with the goal of minimizing cost, minimizing time, maximizing reliability and optimizing quality is established. A non-dominated sorting genetic algorithm based on reference points (NSGA-III) is adopted to solve the model by combining real number matrix coding and crossover and mutation based on real number coding instead of common evolutionary strategy. And an optimal decision strategy based on combination of analytic hierarchy process and entropy value method …

Research On Source Seeking Methods Of Harmful Gas Leakage In Chemical Industry Parks, Zhao Yong, Bin Chen, Xiaodong Wang, Zhengqiu Zhu, Rongxiao Wang, Xiaogang Qiu

Journal of System Simulation

Abstract: Chemical production safety accidents often lead to harmful gas leakage, causing serious environmental damage and casualties. Mastering the information of leaking source quickly can assist in emergency disposal decisions and reduce the harm of accidents. In this paper, Entrotaxis algorithm is used to guide the ground source seeking equipment to move to the vicinity of the leaking source quickly and autonomously in a chemical park scene, and to master the source information. According to the characteristics of the chemical industry park scene, this paper applies intermittent search module into Entrotaxis algorithm and proposes a robust and suitable algorithm (Entrotaxis-Jump …

Multi-Objective Optimization Design Of Aerodynamic Layout For Twin Swept-Wing Aircraft, Yuchang Lei, Dengcheng Zhang, Yanhua Zhang, Guangxu Su, Luo Hao, Zhan Ren

Journal of System Simulation

Abstract: Multi-objective optimization of aerodynamic layout is a key technology in the design of vehicles. The overall configuration of the shape parameters is optimized with a double swept-shaped wave shape as the basic configuration. We use NSGA-Ⅱ multi-objective genetic algorithm, take the aircraft double sweep angle as the design variable, consider the maximum takeoff weight, range, volume ratio and other performance indicators, use Elman neural network to establish the relationship between shape parameters and performance parameters, and establish constraints based on mission planning requirements. The Pareto optimal solution set is obtained by using optimized design and the individuals with …

Fast Simulation Of Yacht In Calm Water Based On Improved Savitsky Method, Xiaochen Li, Yin Yong

Journal of System Simulation

Abstract: An improved Savitsky method is proposed to increase the accuracy of mathematical model of yacht in fast simulation. Three degrees of freedom mathematical model is established to simulate the motion in displacement regime. warped hull forms of yachts are simplified into prismatic hull and improved Savitsky method is used to calculate resistance. The simulation is carried out in pre-planing regime and planing regime. The validity of the proposed method has been assessed by comparing results with previous experimental data, which shows good agreements. The improved method runs well and the result is accurate when it is added to the …

Neglecting A Wind Energy Portfolio Leaves Nebraska Behind Its Neighbors, Conner Vokoun

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Nebraska is a state that prides itself on the productivity of our land. We dutifully don our foam corn hats at Memorial Stadium and boast that Nebraska beef is what’s for dinner. But Nebraska’s land holds an untapped resource that our neighboring states are taking advantage of: wind. Nebraska must adopt a renewable portfolio to double production of wind energy in our state over the next five years. A renewable portfolio is a regulation that sets a minimum amount of power that can be produced by renewable sources, such as solar, wind, and hydroelectric. Currently, Nebraska does not have any …

Subsidize Or Suffer, Dallas Smith

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

The standard for energy production and consumption in the US has historically been the use of coal or oil. In the earliest days of the industrial revolution, coal was king. For a society to achieve such a goal as the expansion and fortification of infrastructure, well, society as a whole, the means absolutely justify the ends. But what if the means of producing energy didn’t have to look like what they did over a hundred years ago? Well they don’t. The use of new renewable, sustainable energy could prove to be beneficial in many aspects, environmental health especially. By subsidizing …

Is More Investment Needed In Solar And Biogas Energy Sources In Rwanda?, Herve Christian Kabanda

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

The Rwanda Third National Communication Under the United Nations Framework Convention on Climate Change mentions that Green House Gas (GHG) emissions per capita increased from 532.39kg (2006) to 676.23kg (2015) with an annual increase of 2.46%. As of 2015, the dominant emissions are from agriculture (70.4%) followed by energy (20.11%). Urea application in agriculture have increased from 1,246,400 to 2,559,000 tons of CO2 eq. Charcoal or wood being the primary source for cooking; emissions from domestic energy use has increased from 626,800 to 741,400 tons of CO2 eq. If such trends continue severe health issues, deforestation, soil erosion and droughts …

People And Planet First—Time Permitting, Jennifer Gilbert

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Is it just me or is there something about election time that makes politicians overly ambitious? The candidates for the 2020 presidential election are fighting to convince American voters they are the best choice. One of the most common tactics for accomplishing this is providing voters with an unattainable amount of promises for making our problems magically disappear. While these ambitions are “attention-grabbing” and somewhat successful in acquiring votes, so many of them go unaccomplished or un-addressed once the candidate enters the white house. No candidate, from any party, is immune to this infectious tendency that accompanies running a campaign. …

The Wind Energy Adaptation Of Nebraska, Samuel Bogert

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

The Wind Energy Adaptation of Nebraska

Today there are many things in the world that we rely on, heaters for warmth, cars for travel, and many other commodities that our way of living is dependent on. One of the most overlooked aspects of society is the need for power. Each and every American is dependent on power somehow, yet the vast majority of us do not think twice when flipping a switch. We all know that flipping a switch means the lights come on, when turning the ignition in our car we don’t think of the process behind the engine …