Digital Commons Network^™

Hyperspectral Point Cloud Projection For The Semantic Segmentation Of Multimodal Hyperspectral And Lidar Data With Point Convolution-Based Deep Fusion Neural Networks, Kevin T. Decker, Brett J. Borghetti

Faculty Publications

The fusion of dissimilar data modalities in neural networks presents a significant challenge, particularly in the case of multimodal hyperspectral and lidar data. Hyperspectral data, typically represented as images with potentially hundreds of bands, provide a wealth of spectral information, while lidar data, commonly represented as point clouds with millions of unordered points in 3D space, offer structural information. The complementary nature of these data types presents a unique challenge due to their fundamentally different representations requiring distinct processing methods. In this work, we introduce an alternative hyperspectral data representation in the form of a hyperspectral point cloud (HSPC), which …

The Characteristics Of Successful Military It Projects: A Cross-Country Empirical Study, Helene Berg, Jonathan D. Ritschel

Faculty Publications

In the armed forces, successful digitalization is crucial to ensure effective operations. Much of the existing literature on project factors during the planning and execution phases of public IT projects do not focus specifically on military sector projects. Therefore, the paper aims to provide empirical insights into the characteristics of successful military IT projects. Data from such projects in NATO countries and agencies were collected through interviews and project documents. The findings relating to the main variable of interest, “delivery of client benefit,” supported previous findings on IT project performance. Medium-sized projects performed better than small and large projects, and …

Gender (In)Equity In Global Mental Health Research: A Call To Action, The Women In Global Mental Health Research Group, Kelly Rose-Clarke

Faculty Publications

In this commentary, we build on work by Gurung and colleagues which highlighted gender inequity in the global mental health research workforce in Nepal (Gurung et al., 2021). We seek to increase awareness of the under-representation of women in global mental health research and its consequences, and we call for change. By women, we refer to all people who identify as women, including trans people. The commentary is informed by conversations with women who are global mental health researchers in the Global North and South at various stages of their careers.

Short-Term Responses Of Soil Carbon, Nitrogen, And Microbial Biomass To Cover Crop Mixtures And Monocultures, Igor Alexandre De Souza, Amanda B. Daly, Jorg Schnecker, Nicholas D. Warren, Adalfredo Rocha Lobo Jr., Richard G. Smith, Andre Fonseca Brito, A. Stuart Grandy

Faculty Publications

Increasingly, cover crops are being adopted for the purpose of improving soil health, yet the timescale and magnitude by which living annual cover crops might modify soil chemical and biological aspects of soil health is not well understood. At the same time, there is growing interest among farmers in cover crop mixtures due to perceptions that species-rich cover crop communities will enhance soil health relative to monocultures. In a field experiment in southeast New Hampshire, we investigated how groups of cover crops grown as monocultures and mixtures for specific seasonal niches (winter/spring, summer, and fall) influenced levels of soil nitrogen …

A Systematic Literature Review Of Cleanroom Ventilation And Air Distribution Systems, Arup Bhattacharya, Mohammad Saleh Nikoopayan Tak, Shervin Shoai-Naini, Fred Betz, Ehsan Mousavi

Faculty Publications

Cleanroom ventilation systems are well-established; however, the advantages and limitations of current practices need to be examined and explained further. This study begins by looking over the history of cleanroom ventilation systems that creates the basis for understanding ventilation rate specifications, terminologies employed in ventilation effectiveness, and recognizing scientific studies that correlate ventilation effectiveness with air change rates. This systematic review includes a comprehensive summary that contains a set of historical data and evidence that may be used to specify ventilation requirements in cleanrooms. Scientific articles are classified in terms of laboratory experiments, simulations/numerical analysis, or hybrid. HVAC designers and …

Review Of Heaven & Earth Grocery, Michael F. Russo

Faculty Publications

No abstract provided.

Extended Sentinel Monitoring Of Helicoverpa Zea Resistance To Cry And Vip3aa Toxins In Bt Sweet Corn: Assessing Changes In Phenotypic And Allele Frequencies Of Resistance, Galen P. Dively, Tom P. Kuhar, Sally V. Taylor, Helene Doughty, Kristian Holmstrom, Daniel O. Gilrein, Brian A. Nault, Joseph Ingerson-Mahar, Anders Huseth, Dominic Reisig, Shelby Fleischer, David Owens, Kelley Tilmon, Francis Reay-Jones, Pat Porter, Jocelyn Smith, Julien Saguez, Jason Wells, Caitlin Congdon, Holly Byker, Bryan Jensen, Chris Difonzo, William D. Hutchison, Eric Burkness, Robert Wright, Michael Crossley, Heather Darby, Tom Bilbo, Nicholas Seiter, Christian Krupke, Craig Abel, Brad S. Coates, Bradley Mcmanus

Faculty Publications

Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020–2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) …

Simulation Of Radioactive Plume Transport In The Atmosphere Including Dynamics Of Particle Aggregation And Breakup, Alexander I. Wiechert, Austin P. Ladshaw, Yong Ha Kim, Costas Tsouris, Sotira Yiacoumi

Faculty Publications

Accurate prediction of the atmospheric transport of debris particles relies heavily on our knowledge of the size distribution of the particles within a debris cloud. Assuming a fixed particle size during simulations is not always viable since the size distribution of the debris can change during transport. Various microphysical processes, such as aggregation and breakup, influence debris particles and dictate any changes to the size distribution. To track those changes that can occur, a population balance model can be adopted and instituted within a model framework. Nonetheless, many of the models that simulate the transport of radioactive debris following a …

The Sound Of Geological Targets On Mars From The Absolute Intensity Of Laser-Induced Sparks Shock Waves, C. Alvarez-Llamas, J. Laserna, J. Moros, P. Purohit, L. García-Gómez, S. M. Angel Ph.D., P. Bernardi, B. Bousquet, A. Cadu, E. Dauson, O. Forni, T. Fouchet, O. Gasnault, X. Jacob, G. Lacombe, N. L. Lanza, C. Larmat, J. Lasue, R. D. Lorenz, P. Y. Meslin, D. Mimoun, F. Montmessin, N. Murdoch, A. M. Ollila, P. Pilleri, N. Randazzo, A. L. Reyes-Newell, S. Schröder, A. Stott, J. Ten Cate, A. Udry, D. Vogt

Faculty Publications

Inspection of geological material is one of the main goals of the Perseverance rover during its journey across the landscape of the Jezero crater in Mars. NASA's rover integrates SuperCam, an instrument capable of performing standoff characterization of samples using a variety of techniques. Among those tools, SuperCam can perform laser-induced breakdown spectroscopy (LIBS) studies to elucidate the chemical composition of the targets of interest. Data from optical spectroscopy can be supplemented by simultaneously-produced laser-produced plasma acoustics in order to expand the information acquired from the probed rocks thanks to the SuperCam's microphone (MIC) as it can be synchronized with …

Measuring Resilience To Sea-Level Rise For Critical Infrastructure Systems: Leveraging Leading Indicators, Lamis Amer, Murat Erkoc, Rusty A. Feagin, Sabarethinam Kameshwar, Katharine J. Mach, Diana Mitsova

Faculty Publications

There has been a growing interest in research on how to define and build indicators of resilience to address challenges associated with sea-level rise. Most of the proposed methods rely on lagging indicators constructed based on the historical performance of an infrastructure sub-system. These indicators are traditionally utilized to build curves that describe the past response of the sub-system to stressors; these curves are then used to predict the future resilience of the sub-system to hypothesized events. However, there is now a growing concern that this approach cannot provide the best insights for adaptive decision-making across the broader context of …

Flammability Properties Of The Pyrolysis Gas Generated From Willow Wood, Maria Mitu, Domnina Razus, Dorin Boldor, Cosmin Marculescu

Faculty Publications

Willow wood presents a real interest for biomass pyrolysis due to its fast growth, renewability, and high energy density. Following the pyrolysis of willow wood in an inert atmosphere, a multi-fuel gaseous mixture was obtained, with the following composition (by volume): 38.20% CO/21.87% H2/17.44% CH4/1.15% O2/17.15% CO2/4.19% N2. The propagation of laminar premixed flames in these multifuel mixtures with air was investigated numerically for initial temperatures from 298 to 500 K, initial pressures from 1 to 20 bar, and fuel equivalence ratios between 0.60 and 2.00. The combustion of these gaseous mixtures as free laminar premixed flames was simulated by …

Accurate Covariance Estimation For Pose Data From Iterative Closest Point Algorithm, Rick H. Yuan, Clark N. Taylor, Scott L. Nykl

Faculty Publications

One of the fundamental problems of robotics and navigation is the estimation of the relative pose of an external object with respect to the observer. A common method for computing the relative pose is the iterative closest point (ICP) algorithm, where a reference point cloud of a known object is registered against a sensed point cloud to determine relative pose. To use this computed pose information in downstream processing algorithms, it is necessary to estimate the uncertainty of the ICP output, typically represented as a covariance matrix. In this paper, a novel method for estimating uncertainty from sensed data is …

Cost Estimation Trends For Major Defense Acquisition Programs, Sammantha Jones, Edward D. White, Jonathan D. Ritschel, Shawn M. Valentine

Faculty Publications

The authors use both descriptive and inferential techniques to investigate average and standard deviation trends in cost estimates for major defense acquisition programs (MDAPs) grouped into decades from the 1970s to 2010s. For total program-cost-growth factors (CGFs), the 2010s exhibited lower CGFs compared to the 1990s. For the program-acquisition-unit cost (PAUC) CGFs, the 2010s appear lower than the 1990s and borderline lower than the 1970s. A statistically significant decreasing trend in the standard deviations of total program CGFs throughout the decades was identified. This lowering variability trend also appeared for PAUC CGFs from the 1980s onward. This finding appears to …

Toward One Health: A Spatial Indicator System To Model The Facilitation Of The Spread Of Zoonotic Diseases, Daniel Jato-Espino, Fernando Mayor-Vitoria, Vanessa Moscardó, Fabio Capra-Ribeiro, Leticia Bartolome Del Pino

Faculty Publications

Recurrent outbreaks of zoonotic infectious diseases highlight the importance of considering the interconnections between human, animal, and environmental health in disease prevention and control. This has given rise to the concept of One Health, which recognizes the interconnectedness of between human and animal health within their ecosystems. As a contribution to the One Health approach, this study aims to develop an indicator system to model the facilitation of the spread of zoonotic diseases. Initially, a literature review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to identify relevant indicators related to One Health. The …

Scalable Preparation Of The Masked Acyl Cyanide Tbs-Mac, Haley Hinton, Jack Patterson, Jared Hume, Krunal Patel, Julie Pigza

Faculty Publications

This paper describes the three-step synthesis of TBS-MAC, a masked acyl cyanide (MAC) and a versatile one-carbon oxidation state three synthon. We have developed a scalable and detailed synthesis that involves: (1) acetylation of malononitrile to form the sodium enolate, (2) protonation of the enolate to form acetylmalononitrile, and (3) epoxidation of the enol, rearrangement to an unstable alcohol, and TBS-protection to form the title compound. Both the sodium enolate and acetylmalononitrile are bench-stable precursors to the intermediate hydroxymalononitrile, which can be converted to other MAC reagents beyond TBS by varying the protecting group (Ac, MOM, EE, etc.).

A Comparison Of Quaternion Neural Network Backpropagation Algorithms, Jeremiah Bill, Bruce A. Cox, Lance Champaign

Faculty Publications

This research paper focuses on quaternion neural networks (QNNs) - a type of neural network wherein the weights, biases, and input values are all represented as quaternion numbers. Previous studies have shown that QNNs outperform real-valued neural networks in basic tasks and have potential in high-dimensional problem spaces. However, research on QNNs has been fragmented, with contributions from different mathematical and engineering domains leading to unintentional overlap in QNN literature. This work aims to unify existing research by evaluating four distinct QNN backpropagation algorithms, including the novel GHR-calculus backpropagation algorithm, and providing concise, scalable implementations of each algorithm using a …

Intrinsic Point Defects (Vacancies And Antisites) In Cdgep2 Crystals, Timothy D. Gustafson, Nancy C. Giles, Peter G. Schunemann, Kevin T. Zawilski, Kent L. Averett, Jonathan E. Slagle, Larry E. Halliburton

Faculty Publications

Cadmium germanium diphosphide (CdGeP₂) crystals, with versatile terahertz-generating properties, belong to the chalcopyrite family of nonlinear optical materials. Other widely investigated members of this family are ZnGeP₂ and CdSiP₂. The room-temperature absorption edge of CdGeP₂ is near 1.72 eV (720 nm). Cadmium vacancies, phosphorous vacancies, and germanium-on-cadmium antisites are present in as-grown CdGeP₂ crystals. These unintentional intrinsic point defects are best studied below room temperature with electron paramagnetic resonance (EPR) and optical absorption. Prior to exposure to light, the defects are in charge states that have no unpaired spins. Illuminating a CdGeP_{2 …}

A Multi-Scale Method For Combined Design And Dispatch Optimization Of Nuclear Hybrid Energy Systems Including Storage, Daniel Hill, Dawson Mccrea, An Ho, Matthew Memmott, Kody Powell, John Hedengren

Faculty Publications

Reliable, carbon-free power generation is increasing in importance. Nuclear-renewable hybrid energy systems (NHES) are a potential solution for current generation challenges, but design and dispatch optimization for these systems remains challenging particularly when stochastic effects, long time horizons and nonlinear modeling are needed. This work presents a multi-scale method for combining the design and dispatch optimization problems for nonlinear NHES over long time horizons. Rather than treating the entire horizon as a single optimization problem, a large number of combined optimization problems are solved for shorter samples of the horizon resulting in distributions of optimal capacities for each of the …

Optimal Estimation Inversion Of Ionospheric Electron Density From Gnss-Pod Limb Measurements: Part I-Algorithm And Morphology, Dong L. Wu, Nimalan Swarnalingam, Cornelius C. J. H. Salinas, Daniel J. Emmons, Tyler C. Summers, Robert Gardiner-Garden

Faculty Publications

GNSS-LEO radio links from Precise Orbital Determination (POD) and Radio Occultation (RO) antennas have been used increasingly in characterizing the global 3D distribution and variability of ionospheric electron density (Ne). In this study, we developed an optimal estimation (OE) method to retrieve Ne profiles from the slant total electron content (hTEC) measurements acquired by the GNSS-POD links at negative elevation angles (ε < 0°). Although both OE and onion-peeling (OP) methods use the Abel weighting function in the Ne inversion, they are significantly different in terms of performance in the lower ionosphere. The new OE results can overcome the large Ne oscillations, sometimes negative values, seen in the OP retrievals in the E-region ionosphere. In the companion paper in this Special Issue, the HmF2 and NmF2 from the OE retrieval are validated against ground-based ionosondes and radar observations, showing generally good agreements in NmF2 from all sites. Nighttime hmF2 measurements tend to agree better than the daytime when the ionosonde heights tend to be slightly lower. The OE algorithm has been applied to all GNSS-POD data acquired from the COSMIC-1 (2006–2019), COSMIC-2 (2019–present), and Spire (2019–present) constellations, showing a consistent ionospheric Ne morphology. The unprecedented spatiotemporal sampling of the ionosphere from these constellations now allows a detailed analysis of the frequency–wavenumber spectra for the Ne variability at different heights. In the lower ionosphere (~150 km), we found significant spectral power in DE1, DW6, DW4, SW5, and SE4 wave components, in addition to well-known DW1, SW2, and DE3 waves. In the upper ionosphere (~450 km), additional wave components are still present, including DE4, DW4, DW6, SE4, and SW4. The co-existence of eastward- and westward-propagating wave4 components implies the presence of a stationary wave4 (SPW4), as suggested by other earlier studies. Further improvements to the OE method are proposed, including a tomographic inversion technique that leverages the asymmetric sampling about the tangent point associated with GNSS-LEO links.

Advancing Flame Retardant Prediction: A Self-Enforcing Machine Learning Approach For Small Datasets, Cheng Yan, Xiang Lin, Xiaming Feng, Hongyu Yang, Patrick Mensah, Guoqiang Li

Faculty Publications

Improving the fireproof performance of polymers is crucial for ensuring human safety and enabling future space colonization. However, the complexity of the mechanisms for flame retardant and the need for customized material design pose significant challenges. To address these issues, we propose a machine learning (ML) framework based on substructure fingerprinting and self-enforcing deep neural networks (SDNN) to predict the fireproof performance of flame-retardant epoxy resins. Our model is based on a comprehensive understanding of the physical mechanisms of materials and can predict fireproof performance and eliminate the needs for properties descriptors, making it more convenient than previous ML models. …

Determining Ion Activity Coefficients In Ion-Exchange Membranes With Machine Learning And Molecular Dynamics Simulations, Hishara Keshani Gallage Dona, Teslim Olayiwola, Luis A. Briceno-Mena, Christopher G. Arges, Revati Kumar, Jose A. Romagnoli

Faculty Publications

The activity coefficients of ions in polymeric ion-exchange membranes (IEMs) dictate the equilibrium partitioning coefficient of the ions between the membrane and the liquid. It also affects ion transport processes, such as conductivity, in ion-exchange membranes. Accurately predicting the ion activity coefficient without experimental data has been elusive as most models are empirical or semi-empirical. This work employs an embedding process that maps microscopic and macroscopic properties for modeling of ion activity coefficients in IEMs with molecular dynamics (MD) and machine learning (ML). This strategy is effective for accurately predicting activity coefficients in various IEM materials, including random copolymer and …

Numerical Simulation Of The Korteweg–De Vries Equation With Machine Learning, Kristina O. F. Williams, Benjamin F. Akers

Faculty Publications

A machine learning procedure is proposed to create numerical schemes for solutions of nonlinear wave equations on coarse grids. This method trains stencil weights of a discretization of the equation, with the truncation error of the scheme as the objective function for training. The method uses centered finite differences to initialize the optimization routine and a second-order implicit-explicit time solver as a framework. Symmetry conditions are enforced on the learned operator to ensure a stable method. The procedure is applied to the Korteweg–de Vries equation. It is observed to be more accurate than finite difference or spectral methods on coarse …

Effects Of Size At Birth On Health, Growth And Developmental Outcomes In Children Up To Age 18: An Umbrella Review, Zeina Jamaluddine, Eman Sharara, Vanessa Helou, Nadine El Rashidi, Gloria Safadi, Nehmat El-Helou, Hala Ghattas Ph.D, Miho Sato, Hannah Blencowe, Oona M.R. Campbell

Faculty Publications

Background Size at birth, an indicator of intrauterine growth, has been studied extensively in relation to subsequent health, growth and developmental outcomes. Our umbrella review synthesises evidence from systematic reviews and meta-analyses on the effects of size at birth on subsequent health, growth and development in children and adolescents up to age 18, and identifies gaps.

Methods We searched five databases from inception to mid-July 2021 to identify eligible systematic reviews and meta-analyses. For each meta-analysis, we extracted data on the exposures and outcomes measured and the strength of the association.

Findings We screened 16 641 articles and identified 302 …

Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude

Faculty Publications

The Santa Barbara Basin naturally experiences transient deoxygenation due to its unique geological setting in the southern California Borderland and seasonal changes in ocean currents. Long-term measurements of the basin showed that anoxic events and subsequent nitrate exhaustion in the bottom waters have been occurring more frequently and lasting longer over the past decade. One characteristic of the Santa Barbara Basin is the seasonal development of extensive mats of benthic nitrate-reducing sulfur-oxidizing bacteria, which are found at the sediment–water interface when the basin's bottom waters reach anoxia but still provide some nitrate. To assess the mat's impact on the benthic …

Algorithm 1035: A Gradient-Based Implementation Of The Polyhedral Active Set Algorithm, William W. Hager, Hongchao Zhang

Faculty Publications

The Polyhedral Active Set Algorithm (PASA) is designed to optimize a general nonlinear function over a polyhedron. Phase one of the algorithm is a nonmonotone gradient projection algorithm, while phase two is an active set algorithm that explores faces of the constraint polyhedron. A gradient-based implementation is presented, where a projected version of the conjugate gradient algorithm is employed in phase two. Asymptotically, only phase two is performed. Comparisons are given with IPOPT using polyhedral-constrained problems from CUTEst and the Maros/Meszaros quadratic programming test set.

Relative Genetic Homogeneity Within A Phenotypically Diverse Group; A Case Of The Lake Tana Labeobarbus (Cyprinidae) Species Flock, Ethiopia, Kebede Beshera

Faculty Publications

The Lake Tana Labeobarbus species flock represents one of the world’s most famous examples of lacustrine species radiations. Previous studies of this group have resulted in the description of at least 15 species based on their differences in functional morphology and definition of two clades (lacustrine and riverine spawning clades) based on life history traits. A total of 166 fish representing 14 Labeobarbus species were genotyped using 10 lineage-specific hexaploid microsatellite loci. Six of these loci were developed for this study based on DNA sequence contigs derived from a microsatellite-enriched genomic library of Labeobarbus intermedius from Lake Tana; the remaining …

Imparting Systems Engineering Experience Via Interactive Fiction Serious Games, Thomas C. Ford, David Long, Echo Ford

Faculty Publications

Serious games for education are becoming increasing popular. Interactive fiction games are some of the most popular in app stores and are also beginning to be heavily used in education to teach analysis and decision-making. Noting that it is difficult for systems engineers to experience all necessary situations which prepare them for the role of a chief engineer, in this paper, we explore the use of interactive fiction serious games to impart systems engineering experience and to teach systems engineering principles. The results of a cognitive viability, qualitative viability, and replayability analysis of 14 systems engineering serious games developed in …

Estimating Intermittency Significance By Means Of Surrogate Data: Implications For Solar Wind Turbulence, Eliza Teodorescu, Marius Mihai Echim, Jay Johnson

Faculty Publications

Introduction: Intermittency is a property of turbulent astrophysical plasmas, such as the solar wind, that implies irregularity and fragmentation, leading to non-uniformity in the transfer rate of energy carried by nonlinear structures from large to small scales. We evaluated the intermittency level of the turbulent magnetic field measured by the Parker Solar Probe (PSP) in the slow solar wind in the proximity of the Sun during the probe’s first close encounter. Methods: A quantitative measure of intermittency could be deduced from the normalized fourth-order moment of the probability distribution functions, the flatness parameter. We calculated the flatness of the magnetic …

A Bit-Parallel Tabu Search Algorithm For Finding Es2 -Optimal And Minimax-Optimal Supersaturated Designs, Luis B. Morales, Dursun A. Bulutoglu

Faculty Publications

We prove the equivalence of two-symbol supersaturated designs (SSDs) with N (even) rows, m columns, s_max=4t+i, where i ∈ {0,2}, t ∈ Z^≥0 and resolvable incomplete block designs (RIBDs) whose any two blocks intersect in at most (N+4t+i)/4 points. Using this equivalence, we formulate the search for two-symbol E(s²)-optimal and minimax-optimal SSDs with s_max ∈ {2,4,6} as a search for RIBDs whose blocks intersect accordingly. This allows developing a bit-parallel tabu search (TS) algorithm. The TS algorithm found E(s²)-optimal and minimax-optimal SSDs achieving the sharpest known E(s²) lower bound with …

Electrical Charge Method For Balancing, Quantifying, And Defining Redox Reactions, Pong Kau Yuen, Cheng Man Diana Lau

Faculty Publications

Redox reactions are important in both theoretical studies and practical uses. The concept is also one of the most difficult to teach and learn (Goes, Nogueira & Fernandez, 2020). In general chemistry textbooks, the oxidation number method is a fundamental approach for counting the number of transferred electrons and understanding redox reactions (Tro, 2020; Chang & Goldsby, 2013). Without knowing oxidation number, redox reactions cannot be defined and balanced. Algebraic methods, such as linear simultaneous equations method (Porter, 1985; Olson, 1997; Kolb, 1979) and matrix method (Blakley, 1982; Risteski, 2011), can balance redox reactions, but they cannot define them chemically. …