2,758 research outputs found
An Optimal Harvesting Strategy of a Three Species Syn-ecosystem with Commensalism and Stochasticity
In this paper we have studied the stability of three typical species syn-ecosystem. The system comprises of one commensal S1 and two hosts S2 and S3 . Both S2 and S2 benefit S1 without getting themselves affected either positively or adversely. Further S2 is a commensal of S3 and S3 is a host of both S1 and S2. Limited resources have been considered for all the three species in this case. The model equations of the system constitute a set of three first order non-linear ordinary differential equations. The possible equilibrium points of the model are identified. We have also studied the local and global stabilities. We have analyzed the bionomic equilibrium and optimal harvesting strategy using Pontryagin’s maximum principle. We have investigated the inhabitant intensities of the fluctuations (variances) around the positive equilibrium due to noise and have investigated the stability. We have also checked the MATLAB numerical simulations for stability of the system
Heat and Mass Transfer Effects of Peristaltic Transport of a Nano Fluid in Peripheral layer
This paper deals with a theoretical investigation of heat and mass transfer effects of peristaltic transport of a nanofluid in peripheral layer. By using appropriate methods, the velocity in the core region as well as in the peripheral region, pressure drop, time averaged flux, frictional force, temperature profile, nanoparticle phenomenon, heat transfer coefficient and mass transfer coefficient of the fluid are investigated, using lubrication theory. Effects of different physical parameters like viscosity ratio, mean radius of the central layer, Brownian motion parameter, thermophoresis parameter, local temperature Grashof number as well as local nanoparticle Grashof number on pressure rise characteristics, frictional force, heat transfer coefficient, mass transfer coefficient, velocity profiles and streamline patterns of the fluid are studied. The computational results are presented in graphical form
Compromise Based Evolutionary Multiobjective Optimization Algorithm for Multidisciplinary Optimization
International audienceMultidisciplinary Design Optimization deals with engineering problems composed of several sub-problems - called disciplines - that can have antagonist goals and thus require to find compromise solutions. Moreover, the sub-problems are often multiobjective optimization problems. In this case, the compromise solutions between the disciplines are often considered as compromises between all objectives of the problem, which may be not relevant in this context. We propose two alternative definitions of the compromise between disciplines. Their implementations within the well-known NSGA-II algorithm are studied and results are discussed
Influence of age of rooted cutting, nitrogen and stage of harvest on growth, yield and quality of patchouli [Pogostemon cablin (Blanco) Benth.]
Field experiments were conducted to study the influence of age of rooted cuttings at the time of planting (30, 40, 50, 60, 70, 80 and 90 days), N levels (0, 50 and 100 kg ha-1) and stage of harvest (once in 4, 5 and 6 months) on yield and oil quality of patchouli [Pogostemon cablin (Blanco) Benth.] under semi-arid tropical climate. The results indicated that planting 30 day old rooted cuttings produced higher plant height, plant canopy and oil yield compared with other treatments. Similarly, application of 100 kg N ha-1 and stage of harvest after six months of planting produced maximum herbage yield, oil yield and oil content compared to other treatments. The highest net return (Rs. 59,550 ha-1) and B:C ratio (1.168) were recorded with the application of 100 kg N ha-1 and stage of harvest once in six months. Oil quality was not influenced by age of the rooted cuttings and N level.
 
MaaSim: A Liveability Simulation for Improving the Quality of Life in Cities
Urbanism is no longer planned on paper thanks to powerful models and 3D
simulation platforms. However, current work is not open to the public and lacks
an optimisation agent that could help in decision making. This paper describes
the creation of an open-source simulation based on an existing Dutch
liveability score with a built-in AI module. Features are selected using
feature engineering and Random Forests. Then, a modified scoring function is
built based on the former liveability classes. The score is predicted using
Random Forest for regression and achieved a recall of 0.83 with 10-fold
cross-validation. Afterwards, Exploratory Factor Analysis is applied to select
the actions present in the model. The resulting indicators are divided into 5
groups, and 12 actions are generated. The performance of four optimisation
algorithms is compared, namely NSGA-II, PAES, SPEA2 and eps-MOEA, on three
established criteria of quality: cardinality, the spread of the solutions,
spacing, and the resulting score and number of turns. Although all four
algorithms show different strengths, eps-MOEA is selected to be the most
suitable for this problem. Ultimately, the simulation incorporates the model
and the selected AI module in a GUI written in the Kivy framework for Python.
Tests performed on users show positive responses and encourage further
initiatives towards joining technology and public applications.Comment: 16 page
Thin films of perfectly polar crystallites with uniaxial orientational ordering
The family of metal-organic complexes,(4-dialkylaminopyridyl)bis(acetylacetonato)zinc(II) which show perfectly polar assembly in the crystalline state are found to grow as orientationally ordered crystallites in vapor deposited thin films on glass substrates. A unique crystallographic axis of the crystallites, the longest unit cell axis in most cases, is oriented perpendicular to the substrate plane. The fact that the current observations cover a family of compounds is novel and of general significance for oriented thin film growth on amorphous substrates. Crystal structure, thin film morphology and second harmonic generation of a representative system are presented; the crystallites in the thin films do not show azimuthal orientational ordering
Multivalency in lectins-a crystallographic,modelling and light-scattering study involving peanut lectin and a bivalent ligand
Multivalency is believed to be important in the activity of lectins, although definitive structural studies on it have been few and far between. We have now studied the complexation of tetravalent peanut lectin with a synthetic compound containing two terminal lactose moieties, using a combination of crystallography, dynamic light scattering and modelling. Light scattering indicates the formation of an apparent dimeric species and also larger aggregates of the tetrameric lectin in the presence of the bivalent ligand. Crystals of presumably crosslinked lectin molecules could be obtained. They diffract poorly, but X-ray data from them are good enough to define the positions of the lectin molecules. Extensive modelling on possible crosslinking modes of protein molecules by the ligand indicated that systematic crosslinking could lead to crystalline arrays. The studies also provided a rationale for crosslinking in the observed crystal structure. The results obtained provide further insights into the general problem of multivalency in lectins. They indicate that crosslinking involving multivalent lectins and multivalent carbohydrates could lead to an ensemble of a finite number of distinct periodic arrays rather than a unique array
Systematics of proton decay of actinides
255-262The phenomenon of proton emission from nuclear ground states limits the possibilities of the creation of more exotic proton rich nuclei that are usually produced by fusion-evaporation nuclear reactions. In the energy domain of radioactivity, proton can be considered as a point charge having highest probability of being present in the parent nucleus. Conclaves et al.1 studied the two-proton radioactivity of nuclei of mass number Aet al.2 reviewed the theories of proton emission to analyse the properties of nuclear matter. Maglione et al.3 analysed the proton emission from the some deformed nuclei. We have studied proton decay in almost all actinide nuclei. We have calculated the energy released during the proton decay (QP), penetration factor (P), and half-lives of proton decay. Proton decay half-lives are also longer than that of other decay modes such as alpha decay and spontaneous fission. To check the Geiger-Nuttal law for proton decay in actinide nuclei, we have plotted the logarithmic proton decay half-lives versus 1/sqrt(Q). The competition of proton decay with different decay modes such as alpha decay and spontaneous fission are also studied. We have also highlighted possible proton emitters with the corresponding energies and half-lives in the actinide region
EP-1207: Can DIBH technique be used for SABR of large and mobile tumors of lung and liver? A clinical study
During earthquakes, melt produced by frictional heating can accumulate on slip surfaces and dramatically weaken faults by melt lubrication. Once seismic slip slows and arrests, the melt cools and solidifies to form pseudotachylytes, the presence of which is commonly used by geologists to infer earthquake slip on exhumed ancient faults. Field evidence suggests that solidified melts may weld seismic faults, resulting in subsequent seismic ruptures propagating on neighboring pseudotachylyte-free faults or joints and thus leading to long-term fault slip delocalization for successive ruptures. We performed triaxial deformation experiments on natural pseudotachylyte-bearing rocks, and show that cooled frictional melt effectively welds fault surfaces together and gives faults cohesive strength comparable to that of an intact rock. Consistent with the field-based speculations, further shear is not favored on the same slip surface, but subsequent failure is accommodated on a new subparallel fault forming on an off-fault preexisting heterogeneity. A simple model of the temperature distribution in and around a pseudotachylyte following slip cessation indicates that frictional melts cool to below their solidus in tens of seconds, implying strength recovery over a similar time scale
Study of Genetic Parameters in F5 Families of Rice (Oryza sativa L.)
One hundred and fourteen F5 families of rice belonging to six crosses along with seven parents were evaluated during kharif, 2015 at Andhra Pradesh Rice Research Institute and Regional Agricultural Research Station, Maruteru to study variability, heritability, genetic advance as per cent of mean and nature and direction of association among themselves and with grain yield. Data was recorded on ten characters which showed significant differences among themselves. High PCV and GCV were observed for grain yield per plant and test weight. High heritability coupled with high genetic advance as per cent of mean was observed for number of grains per panicle, grain yield per plant and test weight indicating the presence of additive gene action in governing the inheritance of these traits. Hence, direct phenotypic selection is useful with respect to these traits
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