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Articles 41791 - 41820 of 294391

Full-Text Articles in Physical Sciences and Mathematics

Early Permian Zircon Ages From The P. Confluens And P. Pseudoreticulata Spore-Pollen Zones In The Southern Bonaparte And Canning Basins, Northwestern Australia, A. J. Mory, J. Crowley, J. Backhouse, R. S. Nicoll, J. D. Gorter Jun 2023

Early Permian Zircon Ages From The P. Confluens And P. Pseudoreticulata Spore-Pollen Zones In The Southern Bonaparte And Canning Basins, Northwestern Australia, A. J. Mory, J. Crowley, J. Backhouse, R. S. Nicoll, J. D. Gorter

Geosciences Faculty Publications and Presentations

The Pseudoreticulatispora confluens–P. pseudoreticulata spore-pollen zonal datum typically coincides with the end of widespread Permian glacial deposits in Western Australia. Although previously attributed to the mid-Sakmarian, chemical abrasion isotope dilution thermal ionisation mass spectrometry (TIMS) dating of zircons from volcanic tuffs in the Ditji Formation of the Bonaparte Basin and the Grant Group in the Canning Basin point to an Asselian age of about 295.25 Ma for this datum. All dated zircons from the Ditji Formation came from petroleum well cuttings but the accompanying palynology was mostly from sidewall cores; however, all Grant Group samples were from conventional core. TIMS …


Iowa Waste Reduction Center Newsletter, June 2023, University Of Northern Iowa. Iowa Waste Reduction Center. Jun 2023

Iowa Waste Reduction Center Newsletter, June 2023, University Of Northern Iowa. Iowa Waste Reduction Center.

Iowa Waste Reduction Center Newsletter

Contents:

--- Save-the-date: Iowa Recycling and Solid Waste Management Conference
--- Save-the-Date: EPA Region 7, Iowa State University
--- EPA Region 7, Iowa State University
--- IWRC and ISU Collaborate to promote sustainable brewing practices
--- From UNI Intern Turned IWRC Professional
--- IWRC Welcomes New Summer Interns
--- Industry News


Learning The Game: Implementations Of Convolutional Networks In Automated Strategy Identification, Cameron Klig Jun 2023

Learning The Game: Implementations Of Convolutional Networks In Automated Strategy Identification, Cameron Klig

Master's Theses

Games can be used to represent a wide variety of real world problems, giving rise to many applications of game theory. Various computational methods have been proposed for identifying game strategies, including optimized tree search algorithms, game-specific heuristics, and artificial intelligence. In the last decade, systems like AlphaGo and AlphaZero have significantly exceeded the performance of the best human players in Chess, Go, and other games. The most effective game engines to date employ convolutional neural networks (CNNs) to evaluate game boards, extract features, and predict the optimal next move. These engines are trained on billions of simulated games, wherein …


2023 June 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Jun 2023

2023 June 1 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.


Representations From Group Actions On Words And Matrices, Joel T. Anderson Jun 2023

Representations From Group Actions On Words And Matrices, Joel T. Anderson

Master's Theses

We provide a combinatorial interpretation of the frequency of any irreducible representation of Sn in representations of Sn arising from group actions on words. Recognizing that representations arising from group actions naturally split across orbits yields combinatorial interpretations of the irreducible decompositions of representations from similar group actions. The generalization from group actions on words to group actions on matrices gives rise to representations that prove to be much less transparent. We share the progress made thus far on the open problem of determining the irreducible decomposition of certain representations of Sm × Sn arising from group actions on matrices.


Predicting Location And Training Effectiveness (Plate), Erik Rolf Bruenner Jun 2023

Predicting Location And Training Effectiveness (Plate), Erik Rolf Bruenner

Master's Theses

Abstract Predicting Location and Training Effectiveness (PLATE)
Erik Bruenner

Physical activity and exercise have been shown to have an enormous impact on many areas of human health and can reduce the risk of many chronic diseases. In order to better understand how exercise may affect the body, current kinesiology studies are designed to track human movements over large intervals of time. Procedures used in these studies provide a way for researchers to quantify an individual’s activity level over time, along with tracking various types of activities that individuals may engage in. Movement data of research subjects is often collected through …


Detecting Coherent Transport Structures In Ocean Surface Flows, Leah Hoogstra Jun 2023

Detecting Coherent Transport Structures In Ocean Surface Flows, Leah Hoogstra

Master's Theses

Ocean surface transport plays a critical role in marine ecosystems, influencing the complex spatiotemporal patterns of both marine species and pollutants. The theory of Lagrangian coherent structures (LCSs) aims to identify fundamental patterns within time-dependent, nonlinear fluid flows. LCSs are material surfaces that act as dividing lines which fluid does not cross for a relevant period of time. LCS theory is still under active development, and there are multiple proposed ways to mathematically determine an LCS. Each proposed mathematical definition aims to capture the same physical properties, and some capture those properties more successfully and consistently than others. Here we …


Neural Tabula Rasa: Foundations For Realistic Memories And Learning, Patrick R. Perrine Jun 2023

Neural Tabula Rasa: Foundations For Realistic Memories And Learning, Patrick R. Perrine

Master's Theses

Understanding how neural systems perform memorization and inductive learning tasks are of key interest in the field of computational neuroscience. Similarly, inductive learning tasks are the focus within the field of machine learning, which has seen rapid growth and innovation utilizing feedforward neural networks. However, there have also been concerns regarding the precipitous nature of such efforts, specifically in the area of deep learning. As a result, we revisit the foundation of the artificial neural network to better incorporate current knowledge of the brain from computational neuroscience. More specifically, a random graph was chosen to model a neural system. This …


Wasm-Pbchunk: Incrementally Developing A Racket-To-Wasm Compiler Using Partial Bytecode Compilation, Adam C. Perlin Jun 2023

Wasm-Pbchunk: Incrementally Developing A Racket-To-Wasm Compiler Using Partial Bytecode Compilation, Adam C. Perlin

Master's Theses

Racket is a modern, general-purpose programming language with a language-oriented focus. To date, Racket has found notable uses in research and education, among other applications. To expand the reach of the language, there has been a desire to develop an efficient platform for running Racket in a web-based environment. WebAssembly (Wasm) is a binary executable format for a stack-based virtual machine designed to provide a fast, efficient, and secure execution environment for code on the web. Wasm is primarily intended to be a compiler target for higher-level languages. Providing Wasm support for the Racket project may be a promising way …


Analyzing Tortuosity In Patterns Formed By Colonies Of Embryonic Stem Cells Using Topological Data Analysis, Jackie Driscoll Jun 2023

Analyzing Tortuosity In Patterns Formed By Colonies Of Embryonic Stem Cells Using Topological Data Analysis, Jackie Driscoll

Master's Theses

Pluripotent stem cells have been observed to segregate into Turing-like patterns during the early stages of Dox-inducible hiPSC differentiation. In this thesis, we de- velop a tool to quantify the tortuosity in the patterns formed by colonies of pluripo- tent stem cells using methods from topological data analysis. We use clustering techniques and the mapper algorithm to create simplicial complexes representing samples of cells and detail a method of evaluating the tortuosity of these complexes. We use the resulting persistence landscapes and their associated norms to evaluate experimental data and simulated data from an agent based model. This thesis finds …


(R2051) Analysis Of Map/Ph1, Ph2/2 Queueing Model With Working Breakdown, Repairs, Optional Service, And Balking, G. Ayyappan, G. Archana Jun 2023

(R2051) Analysis Of Map/Ph1, Ph2/2 Queueing Model With Working Breakdown, Repairs, Optional Service, And Balking, G. Ayyappan, G. Archana

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, a classical queueing system with two types of heterogeneous servers has been considered. The Markovian Arrival Process (MAP) is used for the customer arrival, while phase type distribution (PH) is applicable for the offering of service to customers as well as the repair time of servers. Optional service are provided by the servers to the unsatisfied customers. The server-2 may get breakdown during the busy period of any type of service. Though the server- 2 got breakdown, server-2 has a capacity to provide the service at a slower rate to the current customer who is receiving service …


(R2028) A Brief Note On Space Time Fractional Order Thermoelastic Response In A Layer, Navneet Lamba, Jyoti Verma, Kishor Deshmukh Jun 2023

(R2028) A Brief Note On Space Time Fractional Order Thermoelastic Response In A Layer, Navneet Lamba, Jyoti Verma, Kishor Deshmukh

Applications and Applied Mathematics: An International Journal (AAM)

In this study, a one-dimensional layer of a solid is used to investigate the exact analytical solution of the heat conduction equation with space-time fractional order derivatives and to analyze its associated thermoelastic response using a quasi-static approach. The assumed thermoelastic problem was subjected to certain initial and boundary conditions at the initial and final ends of the layer. The memory effects and long-range interaction were discussed with the help of the Caputo-type fractional-order derivative and finite Riesz fractional derivative. Laplace transform and Fourier transform techniques for spatial coordinates were used to investigate the solution of the temperature distribution and …


(R2030) Generalized Quasilinearization Method For A Initial Value Problem On Time Scales, Şahap Çetin, Yalçın Yılmaz, Coşkun Yakar Jun 2023

(R2030) Generalized Quasilinearization Method For A Initial Value Problem On Time Scales, Şahap Çetin, Yalçın Yılmaz, Coşkun Yakar

Applications and Applied Mathematics: An International Journal (AAM)

We have investigated that the generalized quasilinearization method under some convenient conditions for nonlinear initial value problem (IVP) of dynamic equation on time scale constructed by monotone sequences of function by using comparison theorem that is the solution of linear IVP of dynamic equation on time scale which converge uniformly and monotonically to the unique solution of the original problem, and the convergence is quadratic.


(R2050) Dual Quaternion Matrices And Matlab Applications, Kemal Gökhan Nalbant, Salim Yüce Jun 2023

(R2050) Dual Quaternion Matrices And Matlab Applications, Kemal Gökhan Nalbant, Salim Yüce

Applications and Applied Mathematics: An International Journal (AAM)

There are many studies in the literature on real quaternions and real quaternion matrices. There are few studies in the literature on dual quaternions. Definitions of the matrices of dual quaternions used in this study will be given. The originality of our research, the set of dual quaternion matrix we studied, will be defined for the first time in this study, and its properties will be given. Moreover, this study is critical because it is an applied study related to dual quaternion matrices. It will be easier to solve examples with large matrix sizes with MATLAB. People who use different …


Apatite Reference Materials For Sims Microanalysis Of Isotopes And Trace Elements, James L. Crowley, Mark Schmitz Jun 2023

Apatite Reference Materials For Sims Microanalysis Of Isotopes And Trace Elements, James L. Crowley, Mark Schmitz

Geosciences Faculty Publications and Presentations

Twelve apatite samples have been tested as secondary ion mass spectrometry (SIMS) reference materials. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis shows that the SLAP, NUAN and GR40 apatite gems are internally homogeneous, with most trace element mass fractions having 2 standard deviations (2s) ≤ 2.0%. BR2, BR5, OL2, AFG2 and AFB1, which have U > 63 μg g-1, 206Pb/204Pb > 283, and homogeneous SIMS U-Pb data, have respective isotope dilution thermal ionisation mass spectrometry (ID-TIMS) ages of 2053.83 ± 0.21 Ma, 2040.34 ± 0.09 Ma, 868.87 ± 0.25 Ma, 478.71 ± 0.22 Ma and …


Policy Uncertainty Reduces Green Investment, Mengyu Wang, Jeffrey Wurgler, Hong Zhang Jun 2023

Policy Uncertainty Reduces Green Investment, Mengyu Wang, Jeffrey Wurgler, Hong Zhang

Research Collection Lee Kong Chian School Of Business

Government subsidies are often used to stimulate environment-friendly investment. We find that Chinese firms reduce green investment as the uncertainty of subsidies rises. This effect is identified from weather-driven fluctuations in air pollution that lead to fluctuations in subsidy allocations: Firms in cities where weather-driven subsidy uncertainty is high engage in less green R&D investment, patent applications, and research staff. Industries that are heavy emitters and those focused on environmental technologies are more affected. The results suggest that policy uncertainty may originate not only from political and macroeconomic shocks but from behavioral mechanisms that link policy to salient recent conditions.


Exploring The Mass To Light Ratio Of Massive Galaxies With The Rubin Dp0 Preview Dataset, Denvir Joy Higgins Jun 2023

Exploring The Mass To Light Ratio Of Massive Galaxies With The Rubin Dp0 Preview Dataset, Denvir Joy Higgins

Physics

The Vera C. Rubin Observatory will perform the 10-year long Legacy Survey of Space and Time expected to begin in 2024. LSST will cover the Southern Hemisphere, collecting over two million images with an 8.4-meter telescope and 3200-pixel camera. In collaboration with the scientific community and based on the Outer Rim Simulation \citep{heit19}, the Rubin Observatory released a simulated dataset (DP0) of the data that is expected to be in hand at the 5-year mark. Using this simulated dataset, I have explored the number and luminosity of the most massive local galaxies. Using a sample of the brightest, closest galaxies …


Engaging Students With High-Stakes Problems, Deepak Basyal Jun 2023

Engaging Students With High-Stakes Problems, Deepak Basyal

Mathematics and Statistics

Engaging students in meaningful mathematics problem-solving is the intention of many education stakeholders around the world. Research suggests that the implementation of high-stakes problems in mathematics teaching is one way to strengthen students’ conceptual understanding. Many carefully crafted open-ended problems constitute high-stakes problems, and proper use of such problems in teaching and learning not only encourages learners’ flexible thinking but also helps detect their misconceptions. However, what is less practiced and understood is: how exactly one should aim to implement such problems in a classroom setting. Teaching pre-service middle school teachers for a few years using high-stakes (mostly open-ended problems) …


Western Kentucky University Stormwater Utility Survey 2023, Warren Campbell, Emily G. Davis Jun 2023

Western Kentucky University Stormwater Utility Survey 2023, Warren Campbell, Emily G. Davis

SEAS Faculty Publications

The main goal of this survey is to identify as many U.S. Stormwater Utilities (SWUs) as possible. Because many stormwater professionals do not have the time to respond to questionnaires, our primary method of identification was Internet searches. We searched key terms such as “stormwater utility”, “stormwater fee”, and “drainage fee”. We scoured online municipal codes such as Municode, AmLegal, Sterling, LexisNexis, General Code, and others. We searched through many city web websitesing to find utilities. We have also had many people contact me to update fees and identify new utilities. However, the data primarily comes from Internet sources and …


Assessing Boil Water Notices As Health-Risk Communication: Risk Perceptions, Efficacy, And Compliance During Winter Storm Uri, Ashleigh M. Day, Sydney O'Shay, Khairul Islam, Matthew W. Seeger, Shawn P. Mcelmurry Jun 2023

Assessing Boil Water Notices As Health-Risk Communication: Risk Perceptions, Efficacy, And Compliance During Winter Storm Uri, Ashleigh M. Day, Sydney O'Shay, Khairul Islam, Matthew W. Seeger, Shawn P. Mcelmurry

Open Data at Wayne State

Winter Storm Uri was an extreme disaster that impacted much of the United States during February of 2021. Texas and Oklahoma were generally not prepared for such an event and experienced massive power grid failures. This led to cascading risks including water system disruptions and many boil water notices (BWNs). The breakdown of some communication channels and the inability to enact protective actions due to power outages, as well as travel limitations on public roads, complicated both dissemination and implementation. Under these conditions, a non-representative, cross-sectional, survey was collected to assess individuals experience BWNs and how perceived efficacy impacts compliance. …


Corn Cob And Corn Husk Biochars Enhance The Growth Of Corn (Zea Mays L.) In Fertilized Clay Loam Soil, Arsenio D. Bulfa Jr, Gina Villegas Pangga, Amparo M. Wagan Jun 2023

Corn Cob And Corn Husk Biochars Enhance The Growth Of Corn (Zea Mays L.) In Fertilized Clay Loam Soil, Arsenio D. Bulfa Jr, Gina Villegas Pangga, Amparo M. Wagan

The Philippine Agricultural Scientist

Biochar is a carbon (C) rich material that improves soil quality, increases crop yield, and is produced from biomass pyrolysis under a limited oxygen environment. An experiment laid out in a split-plot, a completely randomized design (CRD) and was conducted to investigate the growth responses of corn-to-corn cob biochar (CCB) (15 t ha-1), and corn husk biochar (CHB) (15 t ha-1) in a Lipa clay loam soil (Typic Eutrudepts) applied with organic fertilizer (OF) (10 t ha-1) and inorganic fertilizer [recommended rate (RR):120 N;60 P2O5-60; K2O …


Dry Matter Production Of Two Rice Cultivars With Contrasting Root Plasticity Expression Under Different Topographic Conditions Subjected To Soil Moisture Fluctuation, Stella Owusu Nketia, Roel Rodriguez Suralta, Yoshiaka Inukai, Shiro Mitsuya, Mana Kano Nakata, Peter Amoako Ofori, Dinh Thi Ngoc Nguyen, Akira Yamauchi Jun 2023

Dry Matter Production Of Two Rice Cultivars With Contrasting Root Plasticity Expression Under Different Topographic Conditions Subjected To Soil Moisture Fluctuation, Stella Owusu Nketia, Roel Rodriguez Suralta, Yoshiaka Inukai, Shiro Mitsuya, Mana Kano Nakata, Peter Amoako Ofori, Dinh Thi Ngoc Nguyen, Akira Yamauchi

The Philippine Agricultural Scientist

In rainfed lowland rice fields characterized by sloping terrains and the presence of a hardpan in a flat topography, plants are often exposed to soil moisture fluctuation (SMF) stress due to erratic rainfall patterns. Root plasticity is one of the key traits that play important roles in plant adaptation under such conditions. In this study, two contrasting genotypes, KDML105 and IRAT109, were examined to quantify the expression of plasticity in root branching at different positions in the toposequence (TP) and in a flat topography with a hardpan, both without a groundwater table, and subjected to SMF. Results showed that KDML105 …


Natural And Anthropogenic Factors Affecting The Development Of Two Highland Agricultural Soils Of Bukidnon, Philippines, Guadalupe D. Calalang, Laurent Bock, Gilles Colinet, Vincent Hallet, Peter Walpole Jun 2023

Natural And Anthropogenic Factors Affecting The Development Of Two Highland Agricultural Soils Of Bukidnon, Philippines, Guadalupe D. Calalang, Laurent Bock, Gilles Colinet, Vincent Hallet, Peter Walpole

The Philippine Agricultural Scientist

This research was conducted in two highland areas of Bukidnon, Philippines: Miarayon, a sub-catchment of the upper Cagayan de Oro River; and Bendum, a sub-catchment of the upper Pulangui River. Due to their pyroclastic parent rock materials, soils in the upper Cagayan de Oro are classified as Andic Cambisol in open and convex positions, and Andic Umbrisol in concave and depressed positions. Soils in the upper Pulangui are classified as Pisoplinthic Acrisol, Ferralic Nitisol, and Acric Nitisol in areas with ultramafic rock parent materials, and Haplic Cambisol with pyroclastic deposits. Element contents in rocks were congruent to the total soil …


Finite Element Analysis Of A Coconut (Cocos Nucifera L.) Climbing Mechanism, Arjay O. Afan, Omar F. Zubia, Adrian A. Borja, Ralph Kristoffer B. Gallegos Jun 2023

Finite Element Analysis Of A Coconut (Cocos Nucifera L.) Climbing Mechanism, Arjay O. Afan, Omar F. Zubia, Adrian A. Borja, Ralph Kristoffer B. Gallegos

The Philippine Agricultural Scientist

A coconut climber mechanism was subjected to Finite Element Analysis (FEA) to improve its overall design and analyze its strength characteristics. The von Mises stress, total deformation, and factor of safety were evaluated using static structural analysis for the seat and pedal assemblies of the mechanism. The design has a minimum yielding factor of safety of 7.03 for the seat assembly and 12.09 for the pedal assembly. If aluminum is used as an alternative to steel, the prototype's weight can be reduced to at least 64.56% without compromising its strength properties. The weight reduction by using aluminum is expected to …


Apex Calculus: Und Edition (June 2023), Gregory Hartman, Department Of Mathematics, University Of North Dakota Jun 2023

Apex Calculus: Und Edition (June 2023), Gregory Hartman, Department Of Mathematics, University Of North Dakota

Open Educational Resources

This text comprises a three–volume series on Calculus. The first part covers material taught in many “Calculus 1” courses: limits, derivatives, and the basics of integration, found in Chapters 1 through 6. The second text covers material often taught in “Calculus 2”: integration and its applications, along with an introduction to sequences, series and Taylor Polynomials, found in Chapters 7 through 10. The third text covers topics common in “Calculus 3” or “Multivariable Calculus”: parametric equations, polar coordinates, vector–valued functions, and functions of more than one variable, found in Chapters 11 through 15. All three are available separately for free. …


A Spectral Classification Of Solvable Lie Algebras, Michael Matthew Muller Jun 2023

A Spectral Classification Of Solvable Lie Algebras, Michael Matthew Muller

Legacy Theses & Dissertations (2009 - 2024)

For a finite dimensional Lie algebra with basis {X1, ..., Xn} wedefine the characteristic polynomial with respect to the adjoint representation using matrix representatives as det (z0*I + z1*ad X1 + ... + zn*ad Xn). Spectral equivalence is defined and used in a new method to classify low dimensional complex solvable Lie algebras. The characteristic polynomial of so-called graphical Lie algebras is also computed.


Avoiding Starvation Of Arms In Restless Multi-Armed Bandit, Dexun Li, Pradeep Varakantham Jun 2023

Avoiding Starvation Of Arms In Restless Multi-Armed Bandit, Dexun Li, Pradeep Varakantham

Research Collection School Of Computing and Information Systems

Restless multi-armed bandits (RMAB) is a popular framework for optimizing performance with limited resources under uncertainty. It is an extremely useful model for monitoring beneficiaries (arms) and executing timely interventions using health workers (limited resources) to ensure optimal benefit in public health settings. For instance, RMAB has been used to track patients’ health and monitor their adherence in tuberculosis settings, ensure pregnant mothers listen to automated calls about good pregnancy practices, etc. Due to the limited resources, typically certain individuals, communities, or regions are starved of interventions, which can potentially have a significant negative impact on the individual/community in the …


Failure Distributions For Parallel Dependent Identical Weibull Components, Gina S. Sigler Jun 2023

Failure Distributions For Parallel Dependent Identical Weibull Components, Gina S. Sigler

Theses and Dissertations

For a parallel system, when one component fails, the failure distribution of the remaining components will have an increased failure rate. This dissertation takes a novel approach to finding the associated failure distribution of the full system using ordinal statistic distributions for correlated Weibull components, allowing for unknown correlations between the dependent components. A Taylor series approximation is presented for the two component; system failure time distributions are also derived for two failures in a two component system, two failures in an n component system, three failures in a three component system, and k failures in an n component system. …


Quantitative Modeling Of Text-Based Intelligence Source Uncertainty, Adam D. Nesmith Jun 2023

Quantitative Modeling Of Text-Based Intelligence Source Uncertainty, Adam D. Nesmith

Theses and Dissertations

An all-source intelligence analyst’s primary job is delivering timely, well-sourced assessments on relevant targets based on uncertain and incomplete information. Each assessment includes a likelihood that the assessment is true, and a confidence level based on the uncertainty of the sources used. Quantitative all-source intelligence analysis is not widely implemented despite the acknowledged limitations of qualitative intelligence assessments and the existence of proposed quantitative methods. This is due to the challenge of quantitatively representing uncertainty in text-based intelligence reporting (i.e., HUMINT, OSINT, SIGINT), which limits the effectiveness and usability of previously suggested methods. This research creates a novel framework for …


Non-Degenerate Two-Photon Absorption And Excited State Line Shapes In Alkali Vapors, Timothy M. True Jun 2023

Non-Degenerate Two-Photon Absorption And Excited State Line Shapes In Alkali Vapors, Timothy M. True

Theses and Dissertations

The rubidium 5S-5D two-photon transitions were probed between 758-798 nm, where a six order of magnitude change in the cross section was observed and the polarization dependence was seen explicitly. Collisional rates are measured in cesium on the 6P-9S and 5D-10F transitions, with broadening rates as large as 710 MHz/Torr and shifting rates as large as 273 MHz/Torr. We observe Stark broadening on the cesium 5D-10F line shape, with Lorentzian width increasing from 200 MHz to 40 GHz. The influence of electron impact is discussed under these conditions and with 0-20 Torr of helium. Cascade amplified spontaneous emission is seen …