scholarly journals THE FIRST AND SECOND VARIATION OF THE TOTAL ENERGY OF CLOSED DUPLEX DNA IN PLANAR CASE

2010 ◽  
Vol 24 (05) ◽  
pp. 587-597 ◽  
Author(s):  
XIAO-HUA ZHOU

DNA's shape mostly lies on its total energy F. Its corresponding equilibrium shape equations can be obtained by classical variation method: letting the first energy variation δ(1)F = 0. Here, we not only provide the first variation δ(1)F but also give the second variation δ(2)F in planar case. Moreover, the general shape equations of DNA are abstained and a mistake in Zhang et al., [Phys. Rev. E70, 051902 (2004)] is pointed out.

2017 ◽  
Vol 1 (1) ◽  
pp. 83
Author(s):  
Sri Sumardiasih ◽  
Agus Supriyanto ◽  
C Cari

<p class="Abstract">Dye-sensitized solar cell (DSSC) is a device that directly converts visible light into electrical energy. In this work we used dye was extracted from Rhoeo spathacea. A natural dye was directly mixed with TiO<sub>2 </sub>anatase to obtain <em>dyed titanium dioxide</em> which can be used as photoanode for DSSC by varying the volume of dye. The first variation is 2 ml dye mixed with 1 ml of TiO<sub>2</sub>, and the second variation is 3 ml dye mixed with 1 ml of TiO<sub>2</sub>. The absorbance spectra of the dye and dye titanium dioxide have been investigated by spectroscopy UV-<em>Visible Lambda </em>25 and the conversion efficiency of dye titanium dioxide used Keithley 2602A meter. The DSSC based on dye titanium dioxide with varying volume of dye showed that the efficiency of the the second variation is 0,033% which is higher than the first variation (0,023%) as obtained from I-V characterization.</p><p class="Abstract"> </p>


1991 ◽  
Vol 117 (3-4) ◽  
pp. 329-380 ◽  
Author(s):  
J. E. Marsden ◽  
T. Ratiu ◽  
G. Raugel

SynopsisThis paper uses symplectic connections to give a Hamiltonian structure to the first variation equation for a Hamiltonian system along a given dynamic solution. This structure generalises that at an equilibrium solution obtained by restricting the symplectic structure to that point and using the quadratic form associated with the second variation of the Hamiltonian (plus Casimir) as energy. This structure is different from the well-known and elementary tangent space construction. Our results are applied to systems with symmetry and to Lie–Poisson systems in particular.


2019 ◽  
Vol 16 (10) ◽  
pp. 1950155 ◽  
Author(s):  
Paul Bracken

A variational approach is given which can be applied to functionals of a general form to determine a corresponding Euler–Lagrange or shape equation. It is the intention to formulate the theory in detail based on a moving frame approach. It is then applied to a functional of a general form which depends on both the mean and Gaussian curvatures as well as the area and volume elements of the manifold. Only the case of a two-dimensional closed manifold is considered. The first variation of the functional is calculated in terms of the variations of the basic variables of the manifold. The results of the first variation allow for the second variation of the functional to be evaluated.


2017 ◽  
Vol 1 (1) ◽  
pp. 83
Author(s):  
Sri Sumardiasih ◽  
Agus Supriyanto ◽  
C Cari

<p class="Abstract">Dye-sensitized solar cell (DSSC) is a device that directly converts visible light into electrical energy. In this work we used dye was extracted from Rhoeo spathacea. A natural dye was directly mixed with TiO<sub>2 </sub>anatase to obtain <em>dyed titanium dioxide</em> which can be used as photoanode for DSSC by varying the volume of dye. The first variation is 2 ml dye mixed with 1 ml of TiO<sub>2</sub>, and the second variation is 3 ml dye mixed with 1 ml of TiO<sub>2</sub>. The absorbance spectra of the dye and dye titanium dioxide have been investigated by spectroscopy UV-<em>Visible Lambda </em>25 and the conversion efficiency of dye titanium dioxide used Keithley 2602A meter. The DSSC based on dye titanium dioxide with varying volume of dye showed that the efficiency of the the second variation is 0,033% which is higher than the first variation (0,023%) as obtained from I-V characterization.</p><p class="Abstract"> </p>


1998 ◽  
Vol 08 (03) ◽  
pp. 321-342 ◽  
Author(s):  
Olivier Devillers ◽  
Mordecai J. Golin

In this paper, we discuss two variations of the two-dimensional post-office problem that arise when the post-offices are n postmen moving with constant velocities. The first variation addresses the question: given a point q0and time t0who is the nearest postman to q0at time t0? We present a randomized incremental data structure that answers the query in expected O( log2n) time. The second variation views a query point as a dog searching for a postman to bite and finds the postman that a dog running with speed vdcould reach first. While it is quite straightforward to design a data structure for the first problem, designing one for the second appears more difficult. We show that if the dog is quicker than all of the postmen then there is a nice correspondence between the problems. This correspondence will permit us to use the data structure developed for the first problem to solve the second one in O( log2n) time as well.The proposed structure is semi-dynamic, that is the set of postmen can be modified by inserting new postmen. A fully dynamic structure that also supports deletions can be obtained, but in that case the query time becomes O( log3n).


2012 ◽  
Vol 182-183 ◽  
pp. 1225-1229
Author(s):  
Qiong Xue ◽  
Xiao Feng Xiao

In this paper, we study a complete -Riemannian manifold whose curvature bounded from below. Let be a compact totally geodesic submanifold of . Then, for any , we can make use of the first variation formula and the second variation formula of distance to prove that is bounded.


2017 ◽  
Vol 2 (1) ◽  
pp. 25
Author(s):  
Putri Virliani ◽  
I Ketut Suastika ◽  
Wasis Dwi Aryawan

One aspect that needs to be studied in submarine design is the hydrodynamic aspect relating to submarine maneuverability. This research begins by calculating the value of drag and lift  on the three variations of the after body’s mini submarine. The first variation as the initial design is rudder and stern plane arranged perpendicularly or named the+ Stern. Then for the second variation made changes to the arrangement of rudder and stern plane in the after body of the mini submarine with + Stern arrangement, the rudder arranged each other crossed so that it resembles the letter X and called the X-Stern arrangement. Further, for the third variation, the upper rudder of the X-Stern arrangement is replaced by the upper rudder of the + Sternarrangement so that it resembles the inverted Y letter and is called the Y-Stern arrangement. Drag and lift are calculated numerically by using ANSYS-CFX software. From the calculation of CFD found that the submarine with after-body Y-Stern arrangement has the smallest drag and lift value.


2012 ◽  
Vol 09 ◽  
pp. 285-292
Author(s):  
ZHONG ZHOU ◽  
MELVIN ZHANG ◽  
FANCHANG HAO ◽  
HON WAI LEONG

We have developed an exact algorithm that solves certain instances of the Reversal Median Problem (RMP) when provided with additional input – the optimal sorting sequences between every pair of genomes. Our algorithm is able to provide an exact solution (the median genome) or determine that it is not able to do so for every instance of the problem. We have also proven the correctness of the algorithm in a theorem. RMP is the problem of finding an ancestral genome (the median) given the gene orders of three genomes. It is commonly encountered when constructing phylogeny, and is NP-hard. Two variations of the RMP were considered. In the first variation, we are given one sorting sequence for each pair of genomes. And in the second variation, we make use of a compact representation of all possible optimal sorting sequences for each pair of genomes that was developed by Braga et al.


2020 ◽  
Vol 10 (1) ◽  
pp. 534-547
Author(s):  
Jifeng Chu ◽  
Joachim Escher

Abstract When the vorticity is monotone with depth, we present a variational formulation for steady periodic water waves of the equatorial flow in the f-plane approximation, and show that the governing equations for this motion can be obtained by studying variations of a suitable energy functional 𝓗 in terms of the stream function and the thermocline. We also compute the second variation of the constrained energy functional, which is related to the linear stability of steady water waves.


Sign in / Sign up

Export Citation Format

Share Document