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2019

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Articles 1 - 30 of 802

Full-Text Articles in Physical Sciences and Mathematics

About Time: Visualizing Time At Burning Man, Gordon D. Hoople, Austin Choi-Fitzpatrick, Nathaniel Parde, Diane Hoffoss, Max Mellette, Rachel Nishimura, Virginia Gutman Dec 2019

About Time: Visualizing Time At Burning Man, Gordon D. Hoople, Austin Choi-Fitzpatrick, Nathaniel Parde, Diane Hoffoss, Max Mellette, Rachel Nishimura, Virginia Gutman

The STEAM Journal

About Time was a 30 foot long, 3000 pound wooden sundial that went up in flames at Burning Man 2019. The piece reflected on the role time plays in our lives. We organize our lives around time—are enslaved to time—and yet we know so little about it. Physicists and philosophers continue to grapple with deep puzzles of time—Is time a fundamental quantity, independent of human actions or observations or is it an emergent property of our perception? This installation projected time using two sundials: a horizontal dial which swept time out across the desert floor and ...


Coal Mining Sector Contribution To Environmental Conditions And Human Development Index In East Kalimantan Province, Kunny Izza Indah Afkarina, Sindhung Wardana, Poerborini Damayanti Dec 2019

Coal Mining Sector Contribution To Environmental Conditions And Human Development Index In East Kalimantan Province, Kunny Izza Indah Afkarina, Sindhung Wardana, Poerborini Damayanti

Journal of Environmental Science and Sustainable Development

Coal mining has been one of the issues that led to pros and cons in Indonesia. Research shows that mining activities are one of the factors that affect people’s incomes and local and national economic development. However, mining is a lucrative activity that leads to construction booms that attract population growth and lead to deforestation, thus affecting the environmental conditions of a region. The coal mining industry of Indonesian province of East Kalimantan, on the island of Borneo, provides most of the economic base needed to build the infrastructure and provide energy of the country. Kalimantan Province accounts for ...


Behind The Trash: A Qualitative Research On How Trash Pickers In Cirendeu Area Contribute To Recycling, Mana Kakinuma Dec 2019

Behind The Trash: A Qualitative Research On How Trash Pickers In Cirendeu Area Contribute To Recycling, Mana Kakinuma

Journal of Environmental Science and Sustainable Development

Trash is one of the most serious environmental issues. People strive to solve the problem with reducing the use of plastic and figuring out the method to recycle efficiently; however, the story of trash pickers is barely on the topic. The problems are the ignorance and underestimation of the society. People should consider the integrated solution for both the environment and those trash pickers. The ideal solution would be formalizing waste disposal system, officially hire trash pickers for their stable life, and let their children access to education for brighter future. This discussion will examine the importance of understanding the ...


Front Matter Dec 2019

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.


Understanding The Impact Of Learning Community Support For Stem Students With Low Mathematics Placement, Ryan D. Sweeder, Merve N. Kursav, Samantha M F Cass, Rebecca L. Matz Dec 2019

Understanding The Impact Of Learning Community Support For Stem Students With Low Mathematics Placement, Ryan D. Sweeder, Merve N. Kursav, Samantha M F Cass, Rebecca L. Matz

Learning Communities Research and Practice

As a residential college within Michigan State University that focuses on STEM fields, Lyman Briggs College developed a STEM learning community to support students with low mathematics placement test scores, the Instilling Quantitative and Integrative Reasoning program (INQUIRE). INQUIRE serves some of those students considered historically at-risk based on STEM retention and graduation rates. INQUIRE was developed as learning community using curricular design, cohort-building activities, and academic resources to assist students’ transition to college. Participating students were surveyed to understand the student experience of INQUIRE. Students’ responses indicated that the program helped them adjust to college, prepare for introductory STEM ...


Sub-Barrier And Above-Barrier Electron Transport Through Multilayer Semiconductors, Vohob R. Rasulov, Rustam Y. Rasulov, Ikbol M. Eshboltaev, Ravshan R. Sultonov Dec 2019

Sub-Barrier And Above-Barrier Electron Transport Through Multilayer Semiconductors, Vohob R. Rasulov, Rustam Y. Rasulov, Ikbol M. Eshboltaev, Ravshan R. Sultonov

Scientific Bulletin. Physical and Mathematical Research

In the article the transparency coefficients of the semiconductor structure, consisting of alternating asymmetric potential barriers and wells, where the Bastard condition is taken into account, are calculated. It is shown that in the structure there should be an oscillation of the transmission coefficient of electrons depending on their energy, which is due to the interference of the de Broglie waves reaching the barrier and reflected from the potential barrier. The electronic states of a multilayer semiconductor structure consisting of alternating potential wells and barriers are analyzed. It has been shown that both in the above-barrier and in the barrier ...


Structure And Electro Physical Properties Of Solid Solution (Si2)1-X(Cds)X (0 £ X £ 0.01), Xurshidjon M. Madaminov Dec 2019

Structure And Electro Physical Properties Of Solid Solution (Si2)1-X(Cds)X (0 £ X £ 0.01), Xurshidjon M. Madaminov

Scientific Bulletin. Physical and Mathematical Research

This paper shows the possibility of obtaining a single-crystal solid solution for the substitution of p-Si-n-(Si2)1-x (CdS)x (0 £ x £ 0.01) on silicon substrates with a diameter of 20 mm and thickness » 400, with a crystallographic orientation (111) n-types of conductivity with a specific resistance of 1 Ω cm, by the method of liquid phase epitaxy from Sn – Si – CdS solution – melt in a hydrogen atmosphere purified by palladium. Perfect epitaxial layers with mirror surfaces and with the best parameters are grown under the following technological conditions: temperatures start crystallization –1150 ОС, speed of forced cooling is ...


Scientific Foundation Of The Rate Of Falling Of Raw Materials On Walnut Breakage Device, Otabek A. Mirzaev, Xolhuzha A. Sobirov, Nusratillo R. Barakaev Dec 2019

Scientific Foundation Of The Rate Of Falling Of Raw Materials On Walnut Breakage Device, Otabek A. Mirzaev, Xolhuzha A. Sobirov, Nusratillo R. Barakaev

Scientific Bulletin. Physical and Mathematical Research

Today, there are many types of fruits that are separated the kernel from the shell: walnuts, almonds, filberts, chestnuts, pistachios and cashews. Nuts have a high calorific value and a rich nutrient composition. The most critical and delicate operation is shell cracking to extract the fragile whole kernel from the shell. Studies on nut rupturing are particularly focused on the following three aspects: the physical characteristics of nuts, the mechanical properties of nut rupturing, and nut rupturing equipment. Determining the velocity of the nut entered into the apparatus will allow the machine to operate normally, but will also increase its ...


Eigenvalue Problems For An Elliptic Equation With Two Singular Coefficients, Asror M. Shokirov Dec 2019

Eigenvalue Problems For An Elliptic Equation With Two Singular Coefficients, Asror M. Shokirov

Scientific Bulletin. Physical and Mathematical Research

For the elliptic type of differential equation with two singular coefficients, the quadratic values of the Dirixle and Dirixle-Neumann problems were found in the quarter in that work. The field and boundary conditions for solving these problems are described in the polar coordinate system. The result is a rectangle in the polar coordinate system. Then, we used the method of separating variables in the right rectangle, that is, divided the variables by the equation and divided the problem into two distinct values for ordinary differential equations. The first of the ordinary differential equations is the substitution of , where the equation ...


Modeling It Of Discourse Analysis And The Ussues Machine Translation, Nilufar Z. Abdurakhmonova, Allayorzhon G. Teshabayev Dec 2019

Modeling It Of Discourse Analysis And The Ussues Machine Translation, Nilufar Z. Abdurakhmonova, Allayorzhon G. Teshabayev

Scientific Bulletin. Physical and Mathematical Research

The aim of the research work is to analyze theories on the formation of linguistic database of the translation program of simple texts from English into Uzbek and to create program foundations. The object of the research work is word combinations and simple sentences of English and Uzbek languages, grammatical expressions as well. Scientific novelty of the research work is as follows: Drawn conclusions provide exactness of translation on creating linguistic database of machine translation. created linguistic database of phrasal verbs, morphological lexicon, affixes of English and Uzbek languages and their morphological and syntactic models; identified coordination of simple sentence ...


Spectral Characteristics Of The Absorption Coefficient And Energy Position Of Defects, Sirojiddin Z. Zaynobidinov, Rustamjon G. Ikramov, Mashhurahon A. Nuriddinova, Khurshid A. Muminov Dec 2019

Spectral Characteristics Of The Absorption Coefficient And Energy Position Of Defects, Sirojiddin Z. Zaynobidinov, Rustamjon G. Ikramov, Mashhurahon A. Nuriddinova, Khurshid A. Muminov

Scientific Bulletin. Physical and Mathematical Research

In this paper, a theoretical method to study the spectral characteristics of the absorption coefficient, namely the area of ​​defective absorption of amorphous hydrogenated silicon according to the Davis-Mott approximation from the Kubo-Greenwood formula. It is shown that using the experimental spectral characteristic of the defect absorption coefficient, one can determine the energy position of defects in the mobility gap. Optical transitions of electrons, in which electronic states participate in defects, indicate that there are three types of optical transitions of electrons: between defects, between defects and tails of allowed zones, and also between defects and allowed zones. It was ...


Features Of The Physical Properties Of The Modified Surface Of The P-Cdte – Znse Film Heterostructure With Deep Impurity Levels, Yuozas Y. Vaytkus, Nodir E. Alimov, Salim M. Otajonov Dec 2019

Features Of The Physical Properties Of The Modified Surface Of The P-Cdte – Znse Film Heterostructure With Deep Impurity Levels, Yuozas Y. Vaytkus, Nodir E. Alimov, Salim M. Otajonov

Scientific Bulletin. Physical and Mathematical Research

This article analyzes the spectrum of the photocurrent in a layered film heterostructure CdTe-ZnSe with deep primesnymi levels. The experimental results demonstrated that the heterostructure CdTe-ZnSe observed a new effect in the measurement of the photoconductivity spectra, depending on the direction of the applied electric field, and the applied field stimulates the emergence of photo-emf. The spectrum of the photocurrent in a layered CdTe- ZnSe heterostructure film with deep impurity levels are considered in the article. It follows from the experimental results that a new effect is observed in the CdTe-ZnSe heterostructure when measuring the photoconductivity spectra depending on the ...


Definition Of Extended Structural Defects In Epitaxial Films Of Znteg‘Gaas Grown By Mbe, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov Dec 2019

Definition Of Extended Structural Defects In Epitaxial Films Of Znteg‘Gaas Grown By Mbe, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov

Scientific Bulletin. Physical and Mathematical Research

The last three decades of the development of solid state physics are characterized by the fact that the main objects of research are increasingly not massive crystals, but thin films, multilayer thin-film systems, conducting filaments and crystallites of small size. Epitaxial films are grown on a substrate of a single crystal of the same or another material. In the first case, the epitaxial layer with the correct technology becomes a natural extension of the substrate. Epitaxial film can be doped with various impurities. To introduce an alloying admixture into the epitaxial film, three methods are used. According to the first ...


Studies Of Tribotechnical Properties Of Composite Polymeric Materials Of Machine Designation, Tojiboy O. Almataev, Nozimbek T. Almataev Dec 2019

Studies Of Tribotechnical Properties Of Composite Polymeric Materials Of Machine Designation, Tojiboy O. Almataev, Nozimbek T. Almataev

Scientific Bulletin. Physical and Mathematical Research

In the given work are experimentally investigated tribotechnical properties as intensity of wear process and factor of a friction composite epoxy the polymeric materials processed by ultrasound. Results of influence of a kind and the maintenance loading on tribotechnical properties composite epoxy polymeric materials depending on modes of ultrasonic processing are received. Correlation dependence of intensity of wear process and factor of a friction composite epoxy coverings from modes of ultrasonic processing is established. It is shown in the work that with an increase in the duration of ultrasonic exposure, the wear rate and the friction coefficient of the coatings ...


Application Of Optoelectron Converters Of Reflective Type For Automation Of Liquid And Gas Version Test Measuring Units, Yuriy G. Shipulin, Otabek T. Almataev Dec 2019

Application Of Optoelectron Converters Of Reflective Type For Automation Of Liquid And Gas Version Test Measuring Units, Yuriy G. Shipulin, Otabek T. Almataev

Scientific Bulletin. Physical and Mathematical Research

This work is devoted to the use of reflective optoelectronic converters for the automation of liquid and gas calibration flowmeter installations. Liquid and gas calibration flowmeter devices are widely used for verification and certification of various liquid and gas flowmeters and meters. The analysis of the principles of construction of a reflective optoelectronic converter for calibration devices is carried out and the basic principles of their construction are determined. A functional diagram of an experimental automated programmable calibration test setup of flow meters, liquid meters developed on the basis of ROC is presented. High accuracy requirements are imposed on the ...


The Task Of Prosecuting Simple Differential Games On The Rectangle, Azizhon O. Zunnunov Dec 2019

The Task Of Prosecuting Simple Differential Games On The Rectangle, Azizhon O. Zunnunov

Scientific Bulletin. Physical and Mathematical Research

The theory of differential games is developed and resulted from modeling technical problems. Some of the problems in differential games theory can be described as controlling two moving objects, i.e. one of them is the follower that tries to catch the other object, and obviously the other object is the runner. The runner tries to run away from the follower. Most of the practical and theoretical IT problems, planning, technical and other challenges will be derived to the differential games theory for resolution. Thus researching this theory is one of most important topics currently. A lot of researchers contributed ...


Description Of 2-Local Two Sided Multiplication On An Algebra Of Matrices, Farhodjon N. Arzikulov, Kamola A. Solijanova Dec 2019

Description Of 2-Local Two Sided Multiplication On An Algebra Of Matrices, Farhodjon N. Arzikulov, Kamola A. Solijanova

Scientific Bulletin. Physical and Mathematical Research

The present paper is devoted to 2-local derivation on associative and Jordan matrix rings. In 1997, P. Semrl introduced the notion of 2-local derivations and described 2-local derivations on the algebra ¬B(H) of all bounded linear operators on the infinite-dimensional separable Hilbert space H. A similar description for the finite-dimensional case appeared later in 2004. In the paper Y. Lin and T. Wong 2-local derivations have been described on matrix algebras over finite dimensional division rings. In 2012 Sh. Ayupov, K. Kudaybergenov suggested a new technique and have generalized the above mentioned results for abritrary Hilbert spaces. Namely they ...


Smart Factories, Dumb Policy? Managing Cybersecurity And Data Privacy Risks In The Industrial Internet Of Things, Scott J. Shackelford Dec 2019

Smart Factories, Dumb Policy? Managing Cybersecurity And Data Privacy Risks In The Industrial Internet Of Things, Scott J. Shackelford

Minnesota Journal of Law, Science & Technology

No abstract provided.


A Theoretical Study An Influence Of Oxygen Group Elements To Rotational Barrier Of 2-(2'-Pyridyl)-1,3,4-Oxa(Thia, Selena And Tellura) Diazoles, Alisher Eshimbetov, Khamza Toshov, Inderpreet Kaur, Alisher Khaitboev Dec 2019

A Theoretical Study An Influence Of Oxygen Group Elements To Rotational Barrier Of 2-(2'-Pyridyl)-1,3,4-Oxa(Thia, Selena And Tellura) Diazoles, Alisher Eshimbetov, Khamza Toshov, Inderpreet Kaur, Alisher Khaitboev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

Surveying of the references shows that selenium and tellurium containing compounds will be one of the most promising heterocycles in the future. Therefore, the influence of oxygen group elements -- O, S, Se and Te to rotational barrier heights of 2-(2'-pyridyl)-1,3,4-oxa (thia, selena and tellura) diazoles were investigated by DFT/def2-TZVP method and also by DFT/6-311G(d) method only for O, S and Se series. And also, their thermodynamic parameters (ΔH,ΔG) were calculated in gas phase. Furthermore, some model compounds with conjugated C=C-C=C, N=C-C=C and N=C-C=N fragments with ...


Identifying Customer Churn In After-Market Operations Using Machine Learning Algorithms, Vitaly Briker, Richard Farrow, William Trevino, Brent Allen Dec 2019

Identifying Customer Churn In After-Market Operations Using Machine Learning Algorithms, Vitaly Briker, Richard Farrow, William Trevino, Brent Allen

SMU Data Science Review

This paper presents a comparative study on machine learning methods as they are applied to product associations, future purchase predictions, and predictions of customer churn in aftermarket operations. Association rules are used help to identify patterns across products and find correlations in customer purchase behaviour. Studying customer behaviour as it pertains to Recency, Frequency, and Monetary Value (RFM) helps inform customer segmentation and identifies customers with propensity to churn. Lastly, Flowserve’s customer purchase history enables the establishment of churn thresholds for each customer group and assists in constructing a model to predict future churners. The aim of this model ...


Personalized Detection Of Anxiety Provoking News Events Using Semantic Network Analysis, Jacquelyn Cheun Phd, Luay Dajani, Quentin B. Thomas Dec 2019

Personalized Detection Of Anxiety Provoking News Events Using Semantic Network Analysis, Jacquelyn Cheun Phd, Luay Dajani, Quentin B. Thomas

SMU Data Science Review

In the age of hyper-connectivity, 24/7 news cycles, and instant news alerts via social media, mental health researchers don't have a way to automatically detect news content which is associated with triggering anxiety or depression in mental health patients. Using the Associated Press news wire, a semantic network was built with 1,056 news articles containing over 500,000 connections across multiple topics to provide a personalized algorithm which detects problematic news content for a given reader. We make use of Semantic Network Analysis to surface the relationship between news article text and anxiety in readers who struggle ...


A Data Science Approach To Defining A Data Scientist, Andy Ho, An Nguyen, Jodi L. Pafford, Robert Slater Dec 2019

A Data Science Approach To Defining A Data Scientist, Andy Ho, An Nguyen, Jodi L. Pafford, Robert Slater

SMU Data Science Review

In this paper, we present a common definition and list of skills for a Data Scientist using online job postings. The overlap and ambiguity of various roles such as data scientist, data engineer, data analyst, software engineer, database administrator, and statistician motivate the problem. To arrive at a single Data Scientist definition, we collect over 8,000 job postings from Indeed.com for the six job titles. Each corpus contains text on job qualifications, skills, responsibilities, educational preferences, and requirements. Our data science methodology and analysis rendered the single definition of a data scientist: A data scientist codes, collaborates, and ...


Investigation Of Isomer Ratios In The Reactions (Γ, N) And (N, 2N) On Nuclei 76Ge And 82Se, Satimbay Palvanov, Turgunali Akhmadzhanov Dec 2019

Investigation Of Isomer Ratios In The Reactions (Γ, N) And (N, 2N) On Nuclei 76Ge And 82Se, Satimbay Palvanov, Turgunali Akhmadzhanov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

The method of the induced activity measured the isomeric yield ratios and cross-sections ratios of reactions (γ, n) and (n, 2n) on nuclei 76Ge and 82Se. Samples of natural have been irradiated in the bremsstrahlung beam of the betatron SB-50 of National University of Uzbekistan in the energy range of 10-35 MeV with energy step of 1 MeV. For 14 MeV neutron irradiation, we used the NG-150 neutron generator of Institute of Nuclear Physics. The gamma spectra reactions products were measured with a spectroscopic system consisting of HPGe detector CANBERRA with energy resolution of 1.8 keV ...


Achieving Optimal Horizontal Drill Operations, Daniel J. Serna, James Vasquez, Donald Markley Dec 2019

Achieving Optimal Horizontal Drill Operations, Daniel J. Serna, James Vasquez, Donald Markley

SMU Data Science Review

In this paper, we present a novel method of predicting the onset of a slide event in horizontal drilling operations. Horizontal drilling operations attempt to create a well through a subsurface as quickly as possible by rotating a drill through the subsurface. A slide event occurs when the drill begins to inefficiently rotate through the subsurface, resulting in a significantly reduced rate of penetration. Slide events can be prevented, or significantly reduced in their impact, when their onset is accurately predicted. We present a method of accurately predicting the onset of slide events with a time-series based predictive model that ...


A Data Driven Approach To Forecast Demand, Hannah Kosinovsky, Sita Daggubati, Kumar Ramasundaram, Brent Allen Dec 2019

A Data Driven Approach To Forecast Demand, Hannah Kosinovsky, Sita Daggubati, Kumar Ramasundaram, Brent Allen

SMU Data Science Review

Abstract. In this paper, we present a model and methodology for accurately predicting the following quarter’s sales volume of individual products given the previous five years of sales data. Forecasting product demand for a single supplier is complicated by seasonal demand variation, business cycle impacts, and customer churn. We developed a novel prediction using machine learning methodology, based upon a Dense neural network (DNN) model that implicitly considers cyclical demand variation and explicitly considers customer churn while minimizing the least absolute error between predicted demand and actual sales. Using parts sales data for a supplier to the oil and ...


Rearrangement Operations On Unrooted Phylogenetic Networks, Remie Janssen, Jonathan Klawitter Dec 2019

Rearrangement Operations On Unrooted Phylogenetic Networks, Remie Janssen, Jonathan Klawitter

Theory and Applications of Graphs

Rearrangement operations transform a phylogenetic tree into another one and hence induce a metric on the space of phylogenetic trees. Popular operations for unrooted phylogenetic trees are NNI (nearest neighbour interchange), SPR (subtree prune and regraft), and TBR (tree bisection and reconnection). Recently, these operations have been extended to unrooted phylogenetic networks, which are generalisations of phylogenetic trees that can model reticulated evolutionary relationships. Here, we study global and local properties of spaces of phylogenetic networks under these three operations. In particular, we prove connectedness and asymptotic bounds on the diameters of spaces of different classes of phylogenetic networks, including ...


Evaluating Data Quality Of Newborn Hearing Screening, Maria C. Sanchez Gomez, Kelly Dundon, Xidong Deng Dec 2019

Evaluating Data Quality Of Newborn Hearing Screening, Maria C. Sanchez Gomez, Kelly Dundon, Xidong Deng

Journal of Early Hearing Detection and Intervention

Scope

Jurisdictional-based Early Hearing Detection and Intervention Information Systems (EHDI-IS) collect data on the hearing screening and follow-up status of infants across the United States. These systems serve as tools that assist EHDI programs’ staff and partners in their tracking activities and provide a variety of data reports to help ensure that all children who are deaf/hard of hearing (D/HH) are identified early and receive recommended intervention services. The quality and timeliness of the data collected with these systems are crucial to effectively meeting these goals.

Methodology

Forty-eight EHDI programs, funded by the Centers for Disease Control and ...


Problems For A Simple Differential Equation Of The First Order Linear That The Right Side Is Unknown And The Coefficient Is Interrupted, Guljahon Ilhomjon Qizi Tillabayeva Dec 2019

Problems For A Simple Differential Equation Of The First Order Linear That The Right Side Is Unknown And The Coefficient Is Interrupted, Guljahon Ilhomjon Qizi Tillabayeva

Scientific Bulletin of Namangan State University

Boundary problems for a differential equation of the first order linear that the right side is unknown and the coefficient is interrupted are presented and studied.


Problematic Education In Mathematics Lessons, Olimjon Odiljon O‘G‘Li Alikhanov Dec 2019

Problematic Education In Mathematics Lessons, Olimjon Odiljon O‘G‘Li Alikhanov

Scientific Bulletin of Namangan State University

This article shows students how to solve problems and examples using problematic teaching methods in mathematics. A new, more advanced explanatory and illustrative methodology has been developed to achieve the goals and objectives of the school. An illustrative study explains the essence of the object being studied, connected with the facts of life, and the author's conclusions with the help of illustrations and various visual aids shown by the teacher in relation to the studied object. end.


On Some Problems Of Theory Of One-Dimensional Bifurcation, Muminjon Tukhtasinov, Kholmurodjon Shermamatovich Qushaqov Dec 2019

On Some Problems Of Theory Of One-Dimensional Bifurcation, Muminjon Tukhtasinov, Kholmurodjon Shermamatovich Qushaqov

Scientific Bulletin of Namangan State University

In the article we consider the systems of differential equations ̇ , that depend on a set of parameters μ. For example, the vector field for the pendulum nominally depends upon two parameters: its length and the strength of gravity. Our goal is to investigate what happens to the flow of the system when parameters vary slightly. Do the properties of the orbits just change slightly, or can orbits be destroyed, created, or otherwise changed dramatically? A bifurcation occurs when there is dramatic change in the dynamics.