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2017

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Articles 11551 - 11580 of 12521

Full-Text Articles in Physical Sciences and Mathematics

Active Site Structures Of Cyp11a1 In The Presence Of Its Physiological Substrates And Alterations Upon Binding Of Adrenodoxin, Qianhong Zhu, Piotr J. Mak, Robert C. Tuckey, James R. Kincaid Jan 2017

Active Site Structures Of Cyp11a1 In The Presence Of Its Physiological Substrates And Alterations Upon Binding Of Adrenodoxin, Qianhong Zhu, Piotr J. Mak, Robert C. Tuckey, James R. Kincaid

Chemistry Faculty Research and Publications

The rate-limiting step in the steroid synthesis pathway is catalyzed by CYP11A1 through three sequential reactions. The first two steps involve hydroxylations at positions 22 and 20, generating 20(R),22(R)-dihydroxycholesterol (20R,22R-DiOHCH), with the third stage leading to a C20–C22 bond cleavage, forming pregnenolone. This work provides detailed information about the active site structure of CYP11A1 in the resting state and substrate-bound ferric forms as well as the CO-ligated adducts. In addition, high-quality resonance Raman spectra are reported for the dioxygen complexes, providing new insight into the status of Fe–O–O fragments encountered during the …

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Recombination Reactions As A Possible Mechanism Of Mass-Independent Fractionation Of Sulfur Isotopes In The Archean Atmosphere Of Earth, Dmitri Babikov Jan 2017

Recombination Reactions As A Possible Mechanism Of Mass-Independent Fractionation Of Sulfur Isotopes In The Archean Atmosphere Of Earth, Dmitri Babikov

Chemistry Faculty Research and Publications

A hierarchy of isotopically substituted recombination reactions is formulated for production of sulfur allotropes in the anoxic atmosphere of Archean Earth. The corresponding system of kinetics equations is solved analytically to obtain concise expressions for isotopic enrichments, with focus on mass-independent isotope effects due to symmetry, ignoring smaller mass-dependent effects. Proper inclusion of atom-exchange processes is shown to be important. This model predicts significant and equal depletions driven by reaction stoichiometry for all rare isotopes: 33S, 34S, and 36S. Interestingly, the ratio of capital Δ values obtained within this model for 33S and 36S is …

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Cofacially Arrayed Polyfluorenes: Spontaneous Formation Of Π-Stacked Assemblies In The Gas Phase, Maxim Vadimovich Ivanov, Neil Reilly, Brandon Uhler, Damian Kokkin, Rajendra Rathore, Scott A. Reid Jan 2017

Cofacially Arrayed Polyfluorenes: Spontaneous Formation Of Π-Stacked Assemblies In The Gas Phase, Maxim Vadimovich Ivanov, Neil Reilly, Brandon Uhler, Damian Kokkin, Rajendra Rathore, Scott A. Reid

Chemistry Faculty Research and Publications

Understanding geometrical and size dependencies of through-space charge delocalization in multichromophoric systems is critical to model electron transfer and transport in materials and biomolecules. In this work, we examine the size evolution of hole delocalization in van der Waals clusters of fluorene (i.e., (F)n), where a range of geometries are possible, reflecting both π-stacking and C–H/π interactions. Using mass-selected two-color resonant two-photon ionization spectroscopy (2CR2PI), we measure electronic spectra and vertical ionization potentials (IPs) in the gas phase. Results are compared with model covalently linked assemblies (denoted Fn), exhibiting a sterically enforced cofacial (i.e., …

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Region Of Smooth Functions For Positive Solutions To An Elliptic Biological Model, Joon Hyuk Kang, Timothy Robertson Jan 2017

Region Of Smooth Functions For Positive Solutions To An Elliptic Biological Model, Joon Hyuk Kang, Timothy Robertson

Faculty Publications

The non-existence and existence of the positive solution to the generalized elliptic model ∆u+g(u v) = 0 in Ω, ∆v+h(u, v) = 0 in Ω, u=v= 0 on∂Ω, were investigated.

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Characterization Of Rectifying And Sphere Curves In R^3, Yun Myung Oh, Julie Logan Jan 2017

Characterization Of Rectifying And Sphere Curves In R^3, Yun Myung Oh, Julie Logan

Faculty Publications

Studies of curves in 3D-space have been developed by many geometers and it is known that any regular curve in 3D space is completely determined by its curvature and torsion, up to position. Many results have been found to characterize various types of space curves in terms of conditions on the ratio of torsion to curvature. Under an extracondition on the constant curvature, Y.L. Seo and Y. M. Oh found the series solution when the ratio of torsion to curvature is a linear function. Furthermore, this solution is known to be a rectifying curve by B. Y. Chen’s work. This …

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Subsurface Transport In A North Inlet, South Carolina Salt Marsh: A Porewater Salinity Model, Carolyn Ryan Jan 2017

Subsurface Transport In A North Inlet, South Carolina Salt Marsh: A Porewater Salinity Model, Carolyn Ryan

Theses and Dissertations

Subsurface transport in coastal salt marshes influences the nutrient budget of coastal environments, but is not fully understood. To expand our understanding of this transport, a simple numerical model was developed. The model simulated vertical transport of salt through the surficial muds at a North Inlet marsh on the coastal plain of South Carolina. To improve the model, a tracer study was utilized to calculate the average velocity of groundwater flow through the system. The model was compared with porewater salinity measured using tension samplers and passive diffusion samplers. Each method produced different, uncorrelated results. However, accounting for macro-pores in …

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The Periodical Winter 2017, Southern Adventist University Jan 2017

The Periodical Winter 2017, Southern Adventist University

the Periodical – Chemistry Department Newsletter

Volume 4, issue 2 of the Periodical includes articles about the Chemistry Club's service activities, a student missions feature, student research at N.C. State, a pictorial directory of May 2017 graduates, and an alumni spotlight.

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Chemical Sensing In Harsh Environments By Multivariate Optical Computing, Christopher Michael Jones Jan 2017

Chemical Sensing In Harsh Environments By Multivariate Optical Computing, Christopher Michael Jones

Theses and Dissertations

Multivariate optical computing (MOC) is a compressive sensing technique for which an analyte concentration is detected in an interfering mixture by direct detector output. The detector measures the dot product of a linear regression vector with a sample spectrum, as an analog optical computation. The computation is accomplished with the multivariate optical element (MOE), to which the optical regression vector is encoded as a transmission pattern. As a spectrum of light emanates from a sample and passes through the MOE, the dot product naturally occurs when light strikes the detector. The MOC platform allows a simple, robust, and direct measurement …

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Asymptotic Properties Of Polynomials Orthogonal Over Multiply Connected Domains, James A. Henegan Jan 2017

Asymptotic Properties Of Polynomials Orthogonal Over Multiply Connected Domains, James A. Henegan

Electronic Theses and Dissertations

We investigate the asymptotic behavior of polynomials orthogonal over certain multiply connected domains. Each domain that we consider has an analytic boundary and is, in a strong sense, conformally equivalent to a canonical type of multiply connected domain called a circular domain. The two most general results involve the construction of a series expansion and an integral representation for these polynomials. We show that the integral representation can be utilized to derive more specific results when the domain of orthogonality is circular. In this case, we shed light on the manner in which the holes in the domain of orthogonality …

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Free Storage Basis Conversion Over Finite Fields, Ersan Akyildiz, Ndangang Yampa Harold, Ahmet Sinak Jan 2017

Free Storage Basis Conversion Over Finite Fields, Ersan Akyildiz, Ndangang Yampa Harold, Ahmet Sinak

Turkish Journal of Mathematics

Representation of a field element plays a crucial role in the efficiency of field arithmetic. If an efficient representation of a field element in one basis exists, then field arithmetic in the hardware and/or software implementations becomes easy. Otherwise, a basis conversion to an efficient one is searched for easier arithmetic. However, this conversion often brings a storage problem for transition matrices associated with these bases. In this paper, we study this problem for conversion between normal and polynomial bases in the extension field $\mathbb{F}_{q^p}$ over $\mathbb{F}_q$ where $q=p^n$. We construct transition matrices that are of a special form. This …

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Near Optimal Step Size And Momentum In Gradient Descent For Quadratic Functions, Engi̇n Taş, Memmedağa Memmedli̇ Jan 2017

Near Optimal Step Size And Momentum In Gradient Descent For Quadratic Functions, Engi̇n Taş, Memmedağa Memmedli̇

Turkish Journal of Mathematics

Many problems in statistical estimation, classification, and regression can be cast as optimization problems. Gradient descent, which is one of the simplest and easy to implement multivariate optimization techniques, lies at the heart of many powerful classes of optimization methods. However, its major disadvantage is the slower rate of convergence with respect to the other more sophisticated algorithms. In order to improve the convergence speed of gradient descent, we simultaneously determine near-optimal scalar step size and momentum factor for gradient descent in a deterministic quadratic bowl from the largest and smallest eigenvalues of the Hessian. The resulting algorithm is demonstrated …

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On The Attached Prime Ideals Of Localcohomology Modules Defined By A Pair Of Ideals, Zohreh Habibi, Maryam Jahangiri, Khadijeh Ahmadi Amoli Jan 2017

On The Attached Prime Ideals Of Localcohomology Modules Defined By A Pair Of Ideals, Zohreh Habibi, Maryam Jahangiri, Khadijeh Ahmadi Amoli

Turkish Journal of Mathematics

Let $I$ and $J$ be two ideals of a commutative Noetherian ring $R$ and $M$ be an $R$-module of dimension $d$. For each $i\in N_0$ let $H^{i}_{I,J}(-)$ denote the $i$-th right derived functor of $\Gamma_{I,J}(-)$, where $\Gamma _{I,J}(M):=\{x \in M : I^{n}x\subseteq Jx \ \text {for} \ n\gg 1\}$. If $R$ is a complete local ring and $M$ is finite, then attached prime ideals of $H^{d-1}_{I,J}(M)$ are computed by means of the concept of co-localization. Moreover, we illustrate the attached prime ideals of $H^{t}_{I,J}(M)$ on a nonlocal ring $R$, for $t= \dim M$ and $t= (I,J,M)$, where $(I,J,M)$ is the …

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Characterization Of Substantially And Quasi-Substantially Efficient Solutions In Multiobjective Optimization Problems, Latif Pourkarimi, Masoud Karimi Jan 2017

Characterization Of Substantially And Quasi-Substantially Efficient Solutions In Multiobjective Optimization Problems, Latif Pourkarimi, Masoud Karimi

Turkish Journal of Mathematics

In this paper, we study the notion of substantial efficiency for a given multiobjective optimization problem. We provide two characterizations for substantially efficient solutions: the first one is based on a scalar problem and the second one is in terms of a stability concept. Moreover, this paper introduces the notion of quasi-substantial efficiency. Similar to those of substantial efficiency, two characterizations for quasi-substantially efficient solutions are obtained.

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Nonpolynomial Spline Technique For The Solution Of Ninth Order Boundary Value Problems, Ghazala Akram, Zara Nadeem Jan 2017

Nonpolynomial Spline Technique For The Solution Of Ninth Order Boundary Value Problems, Ghazala Akram, Zara Nadeem

Turkish Journal of Mathematics

In this paper, a nonpolynomial spline technique is applied to solve the ninth order linear special case boundary value problems. The end conditions are derived to complete the definition of a spline. Three examples are numerically illustrated to check the efficiency of the method. The comparative analysis shows that the proposed technique gives better results than the homotopy perturbation method and the modified variational iteration method.

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Computation Of Conditional Expectation Based On The Multidimensional J-Process Using Malliavin Calculus Related To Pricing American Options, Mohamed Kharrat Jan 2017

Computation Of Conditional Expectation Based On The Multidimensional J-Process Using Malliavin Calculus Related To Pricing American Options, Mohamed Kharrat

Turkish Journal of Mathematics

In this work, we extend the uni-dimensional results, already found by Jerbi and Kharrat, for the multidimensional case: we compute the Malliavin weights related to the conditional expectation $\mathbb{E}(P_{t}(X_{t}) (X_{s}))$ for $0 \leq s \leq t$, where the only state variable follows a multidimensional J-process.

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Asymptotic Stability Of Solutions For A Certain Non-Autonomous Second-Order Stochastic Delay Differential Equation, Ahmed Mohamed Abou-El-Ela, Abdel-Rahiem Sadek, Ayman Mohammed Mahmoud, Eman Sayed Farghaly Jan 2017

Asymptotic Stability Of Solutions For A Certain Non-Autonomous Second-Order Stochastic Delay Differential Equation, Ahmed Mohamed Abou-El-Ela, Abdel-Rahiem Sadek, Ayman Mohammed Mahmoud, Eman Sayed Farghaly

Turkish Journal of Mathematics

In this paper, sufficient criteria that guarantee the existence of stochastic asymptotic stability of the zero solution of the nonautonomous second-order stochastic delay differential equation \eqref{3e1} were established with the aid of a suitable Lyapunov functional. Two examples are given in the last section to illustrate our main result.

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Application Of A Generalised Function Method To The Infinitely Deep Square Well Problem, Basri̇ Ünal Jan 2017

Application Of A Generalised Function Method To The Infinitely Deep Square Well Problem, Basri̇ Ünal

Turkish Journal of Mathematics

The Schrödinger equation for the eigenvalues of the infinitely deep square well potential is solved within the class of generalised functions. It is found that the ground state consists of a step function like eigenfunction with the eigenvalue zero.

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On The 3-Dimensional Hopf Bifurcation Via Averaging Theory Of Third Order, Elouahma Bendib, Sabrina Badi, Ammar Makhlouf Jan 2017

On The 3-Dimensional Hopf Bifurcation Via Averaging Theory Of Third Order, Elouahma Bendib, Sabrina Badi, Ammar Makhlouf

Turkish Journal of Mathematics

We apply the averaging theory of third order to polynomial quadratic vector fields in $\mathbb{R}^3$ to study the Hopf bifurcation occurring in that polynomial. Our main result shows that at most $10$ limit cycles can bifurcate from a singular point having eigenvalues of the form $\pm bi$ and $0$. We provide an example of a quadratic polynomial differential system for which exactly $10$ limit cycles bifurcate from a such singular point.

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Almost Contact Metric Structures Induced By $G_2$ Structures, Nüli̇fer Özdemi̇r, Mehmet Solgun, Şi̇ri̇n Aktay Jan 2017

Almost Contact Metric Structures Induced By $G_2$ Structures, Nüli̇fer Özdemi̇r, Mehmet Solgun, Şi̇ri̇n Aktay

Turkish Journal of Mathematics

We study almost contact metric structures induced by 2-fold vector cross products on manifolds with $G_2$ structures. We get some results on possible classes of almost contact metric structures. Finally, we give examples.

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A Characterization Of Nonprime Powers, Raul Duran Diaz, Luis Hernandez Encinas, Agustin Martin Muñoz, Jaime Muñoz Masque, Seok-Zun Song Jan 2017

A Characterization Of Nonprime Powers, Raul Duran Diaz, Luis Hernandez Encinas, Agustin Martin Muñoz, Jaime Muñoz Masque, Seok-Zun Song

Turkish Journal of Mathematics

A criterion is presented in order to decide whether agiven integer is a prime power or not. The criterion associatesto each positive integer $m$ a finite set of integers$\mathcal{S}(m)$, each of them $\le m $ and the propertiesof this set are studied. The notion of complementary pairsin $\mathcal{S}(m)$ is introduced and it is proved that if one isable to determine a complementary pair $n,n^\prime $, thena partial factorization of the odd integer $m$ can be obtainedin polynomial time. Some particular cases and examples of these resultsare given.

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On Tetravalent Normal Edge-Transitive Cayley Graphs On The Modular Group, Hesam Sharifi, Mohammad Reza Darafsheh Jan 2017

On Tetravalent Normal Edge-Transitive Cayley Graphs On The Modular Group, Hesam Sharifi, Mohammad Reza Darafsheh

Turkish Journal of Mathematics

A Cayley graph $\Gamma=Cay(G, S)$ on a group $G$ with respective toa subset $S\subseteq G$, $S=S^{-1}, 1\notın S$, is said to be normaledge-transitive if $N_{\mathbb{A}ut(\Gamma)}(\rho(G))$ is transitiveon edges of $\Gamma$, where $\rho(G)$ is a subgroup of $\mathbb{A}ut(\Gamma)$isomorphic to $G$. We determine all connected tetravalent normaledge-transitive Cayley graphs on the modular group of order $8n$in the case that every element of $S$ is of order $4n$.

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On Hölder Continuity Of Approximate Solution Maps To Vector Equilibrium Problems, Lam Quoc Anh, Kien Trung Nguyen, Tran Ngoc Tam Jan 2017

On Hölder Continuity Of Approximate Solution Maps To Vector Equilibrium Problems, Lam Quoc Anh, Kien Trung Nguyen, Tran Ngoc Tam

Turkish Journal of Mathematics

In this article, we considerparametric vector equilibrium problems in normed spaces. Sufficientconditions for Hölder continuity of approximate solution mappingswhere they are set-valued are established. As applications of theseresults, the Hölder continuity of the approximate solutionmappings for vector optimization problems and vector variationalinequalities are derived at the end of the paper. Our results arenew and include the existing ones in the literature.

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On Generalized Kropina Change Of $M$Th Root Finsler Metrics With Special Curvature Properties, Bankteshwar Tiwari, Ghanashyam Kr. Prajapati Jan 2017

On Generalized Kropina Change Of $M$Th Root Finsler Metrics With Special Curvature Properties, Bankteshwar Tiwari, Ghanashyam Kr. Prajapati

Turkish Journal of Mathematics

In the present paper, we consider generalized Kropina change of $m$th root Finsler metrics and prove that every generalized Kropina change of $m$th root Finsler metrics with isotropic Berwald curvature, isotropic mean Berwald curvature, relatively isotropic Landsberg curvature, and relatively isotropic mean Landsberg curvature reduces to the Berwald metric, weakly Berwald metric, Landsberg metric, and weakly Landsberg metric, respectively. We also show that every generalized Kropina change of $m$th root Finsler metrics with almost vanishing $\textbf{H}$-curvature has vanishing $\textbf{H}$-curvature.

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Reactive Power Optimization In A Power System Network Through Metaheuristic Algorithms, Chandragupta Mauryan Kuppamuthu Sivalingam, Subramanian Ramachandran, Purrnimaa Shiva Sakthi Rajamani Jan 2017

Reactive Power Optimization In A Power System Network Through Metaheuristic Algorithms, Chandragupta Mauryan Kuppamuthu Sivalingam, Subramanian Ramachandran, Purrnimaa Shiva Sakthi Rajamani

Turkish Journal of Electrical Engineering and Computer Sciences

Reactive power optimization (RPO) in a power system is a rudimentary necessity for the reduction of the loss of power. For the requirement of a unity power factor in the RPO system, the reduction of the system losses is ensured. The pivotal requirements of a power system are inclusive of a perfect compensation technique and methodology for stable reactive power compensation. The proposed concept in this paper utilizes the different reactive power optimization algorithms and performs a comparison. The process is accomplished by the use of IEEE 6-bus, 14-bus, and 30-bus systems to test the optimization technique. The conclusive information …

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Low Complexity Link Level Performance Prediction For Simo Systems, Asif Khan, Alam Zaib, Shahid Khattak Jan 2017

Low Complexity Link Level Performance Prediction For Simo Systems, Asif Khan, Alam Zaib, Shahid Khattak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a low-cost link level performance prediction technique is proposed for a single input and multiple output system. Receiver link level abstraction is used in system level simulations of large networks in order to reduce their complexity. Usually, a single lookup table is employed in link level abstraction to predict a receiver's performance under different channel conditions. In the presented work, the mean frame error rate curve of different diverse channels is proposed as the reference for performance prediction in single input multiple output systems. Its generation involves compression of the received code word into a single quality …

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ผลของตัวเร่งปฏิกิริยาของสารประกอบเชิงซ้อนคอปเปอร์-แอมีนกับเทอเทียรีแอมีนต่อการเตรียมโฟมพอลิยูรีเทนแบบแข็ง, ชาภิชญ์ จันทรสร Jan 2017

ผลของตัวเร่งปฏิกิริยาของสารประกอบเชิงซ้อนคอปเปอร์-แอมีนกับเทอเทียรีแอมีนต่อการเตรียมโฟมพอลิยูรีเทนแบบแข็ง, ชาภิชญ์ จันทรสร

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้ศึกษาเกี่ยวกับผลการเสริมกันของตัวเร่งปฏิกิริยาร่วมระหว่างสารประกอบเชิงซ้อนคอปเปอร์-แอมีนกับตัวเร่งปฏิกิริยาทางการค้าต่อการเตรียมโฟมพอลิยูรีเทนแบบแข็ง สารประกอบเชิงซ้อนคอปเปอร์-แอมีนที่สังเคราะห์ขึ้น คือ สารประกอบเชิงซ้อนคอปเปอร์-เอทิลีนไดแอมีน [Cu(OAc)2(en)2] และ สารประกอบเชิงซ้อนคอปเปอร์-ไตรเอทิลีนเตตระมีน [Cu(OAc)2(trien)] ในรูปแบบสารละลายในเอทิลีนไกลคอล ตัวเร่งปฏิกิริยาทางการค้าที่ใช้มี 3 ชนิด คือ ไดเมทิลไซโคลเฮกซิลแอมีน (DMCHA) และไตรเอทิลีนไดแอมีน (TEDA) ซึ่งเป็นตัวเร่งปฏิกิริยาประเภทเทอเทียรีแอมีน และโพแทสเซียมออกโทเอต (KOct) พิสูจน์เอกลักษณ์ของสารประกอบเชิงซ้อนคอปเปอร์-แอมีนโดยใช้เทคนิคยูวี-วิสิเบิลสเปกโทรสโกปี และเอฟทีไออาร์สเปกโทรสโกปี ศึกษาการเตรียมโฟมพอลิยูรีเทนแบบแข็งด้วยระบบตัวเร่งปฏิกิริยาร่วม 6 ระบบ คือ Cu(OAc)2(en)2 : DMCHA, Cu(OAc)2(trien) : DMCHA, Cu(OAc)2(en)2 : TEDA, Cu(OAc)2(trien) : TEDA, Cu(OAc)2(en)2 : KOct และ Cu(OAc)2(trien) : KOct โดยศึกษาเวลาที่ใช้ในการเกิดปฏิกิริยา คือ เวลาเกิดครีม, เวลาเกิดเจล, เวลาที่โฟมไม่เกาะติดกับผิววัสดุ และเวลาที่โฟมหยุดฟู พิสูจน์เอกลักษณ์โฟมที่ได้ด้วยเอทีอาร์-เอฟทีไออาร์สเปกโทรสโกปี จากผลการทดลองพบว่าตัวเร่งปฏิกิริยาร่วม Cu(OAc)2(en)2 : DMCHA และ Cu(OAc)2(trien) : DMCHA สามารถเร่งปฏิกิริยาได้เร็วกว่าการใช้ตัวเร่งปฏิกิริยาชนิดเดียว คือ Cu(OAc)2(en)2 หรือ Cu(OAc)2(trien) หรือ DMCHA โดยดูได้จากเวลาที่โฟมไม่เกาะติดกับผิววัสดุมีค่าลดลง โฟมพอลิยูรีเทนแบบแข็งที่เตรียมได้จาก Cu(OAc)2(en)2 : DMCHA และ Cu(OAc)2(trien) : DMCHA มีสมบัติเชิงกายภาพและสมบัติเชิงกลที่ดีเทียบเท่ากับโฟมที่เตรียมจาก DMCHA

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Visualizing Morphogenesis With The Processing Programming Language, Avik Patel, Amar Bains, Richard Millet, Tamira Elul Jan 2017

Visualizing Morphogenesis With The Processing Programming Language, Avik Patel, Amar Bains, Richard Millet, Tamira Elul

Faculty Publications & Research of the TUC College of Osteopathic Medicine

We used Processing, a visual artists’ programming language developed at MIT Media Lab, to simulate cellular mechanisms of morphogenesis – the generation of form and shape in embryonic tissues. Based on observations of in vivo time-lapse image sequences, we created animations of neural cell motility responsible for elongating the spinal cord, and of optic axon branching dynamics that establish primary visual connectivity. These visual models underscore the significance of the computational decomposition of cellular dynamics underlying morphogenesis.

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A Proposed Local Instruction Theory For Teaching Instantaneous Speed In Grade Five, Huub De Beer, Koeno Gravemeijer, Michiel Van Eijck Jan 2017

A Proposed Local Instruction Theory For Teaching Instantaneous Speed In Grade Five, Huub De Beer, Koeno Gravemeijer, Michiel Van Eijck

The Mathematics Enthusiast

In answer to a call for innovative science and technology education in primary education, we started a design research project to explore how to teach instantaneous speed in grade five. In this article we present the results of a series of teaching experiments that were conducted to design, try out, and improve a local instruction theory on teaching instantaneous speed in grade five. In a retrospective analysis, looking for patterns in the whole data set, encompassing all experiments, we identified a set of key learning moment of the students. Based on these patterns, a potentially viable local instruction theory was …

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A 21st Century Economic, Educational And Ethical Mathematics Curriculum Policy, Glen S. Aikenhead Jan 2017

A 21st Century Economic, Educational And Ethical Mathematics Curriculum Policy, Glen S. Aikenhead

The Mathematics Enthusiast

Reformulating a mathematics curriculum is a political act, contextualized by economic, educational and ethical considerations, among others. This article represents a political rendition of a rationale to update the Saskatchewan, Canada, curriculum so it harmonizes with a cultural understanding of school mathematics (Ernest, 1988). By revisiting the 19th century definition of school mathematics that we generally follow today, its economic, educational and ethical consequences seem contrary to the expectations of 21st century Saskatchewan.The article’s point form organization, uninterrupted by the appearance of references, conforms to the genre of submissions to government committees. However, footnotes will clarify information for readers unfamiliar …

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New Statistical Randomness Tests: 4-Bit Template Matching Tests, Fati̇h Sulak Jan 2017

New Statistical Randomness Tests: 4-Bit Template Matching Tests, Fati̇h Sulak

Turkish Journal of Mathematics

For cryptographic algorithms, secret keys should be generated randomly as the security of the system depends on the key and therefore generation of random sequences is vital. Randomness testing is done by means of statistical randomness tests. In this work, we show that the probabilities for the overlapping template matching test in the NIST test suite are only valid for a specific template and need to be recalculated for the other templates. We calculate the exact distribution for all 4-bit templates and propose new randomness tests, namely template matching tests. The new tests can be applied to any sequence of …

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