دانلود گزارش کارورزی و کار آموزی

چکیده : 

Zebrafish were tested in an appetitive Pavlovian delayed conditioning task. After an intertrial interval of

k*T s (; , 16 or 32 s), a small, translucent vertical pole was illuminated (CS) for T s. Food was

presented at T/2 s. Pole-biting response latencies from CS onset were a linear function of the food delay

T/2, with slope approximating unity (proportional timing), and standard deviation proportional to latency

(scalar timing). Response latencies tracked changes in food delays even when they changed every other

day. These findings are significant because the zebrafish genome has recently been sequenced, opening

the door to studies in the genetics of interval timing.

چکیده : 

Two experiments with toads were designed to test the memory-decay hypothesis that extinction (i.e.,nonreinforced) performance is a function of time since the last reinforcement. In Experiment 1, toads(Rhinella arenarum, formerly Bufo arenarum) received 15 daily acquisition trials each reinforced withaccess to water during 300 s in a runway and were then randomly assigned to one of 6 retention intervals(RIs): 1, 4, 8, 16, 32, and 64 days. Extinction started after the RI and lasted 8 additional daily trials.Overall extinction performance was a logarithmic function of the RI. Although 4 extinction trials producedsimilar performance than 4 days of RI (consistent with memory decay), 8 extinction trials produced lowerperformance than 8 days of RI (consistent with a decremental effect of nonreinforcement). In Experiment2, two groups of toads received 15 daily acquisition trials each reinforced with access to water for either 30or 600 s, thus producing two reward magnitudes. After an 8-day RI, extinction performance was weakerafter training with the small, than with the large reward magnitude. These results suggest that, at leastin early extinction, the instrumental performance of toads is strongly influenced by the time since thelast reinforcement.

چکیده : 

Laboratory tests and discrete element method simulations were conducted to evaluate regions of validity

of two basic contact models to describe flow rate of rapeseeds through horizontal orifice. Rectangular

container of 50 by 50 mm cross section, 50 mm high, having hopper of 30 in inclination was used to hold

seeds. Bedding of 10,000 seeds was generated in preparatory container and then discharged through

square orifice of 12, 14 or 16 mm side to similar lower container. This was equipped with independent

floor supported on load cell to measure the weight of seeds during discharge of the upper container.

Rapeseeds of moisture content of 5.5% and 15% were used for testing. DEM simulations were performed

in geometrical setup similar to laboratory equipment using spherical particles with material parameters

of rapeseeds. Two contact models were used in simulations that were previously found to adequately

represent impact of dry and wet seeds against flat surface. In laboratory testing mass flow rates of dry

rapeseeds (5.5% M.C.) through the orifices were higher than that of wet (15% M.C.) seeds. In the simulations

no difference in mass flow rates of dry and wet seeds was found if the mass flow rates were calculated

as a sum of masses of particles falling into the receiving container per time unit. However,

difference in the mass flow rates was observed if they were calculated using sum of vertical forces

exerted by particles on walls and floor of receiving container. Simulations revealed that proposed contact

models reproduced well experimental results for slow particle flow but for higher flow rates the models

need to be improved by inclusion of dissipative term.

چکیده : 

A number of different analytical and numerical methods have previously been proposed to estimate solar

cell/module parameters. For a single diode model, the parameters include the photocurrent, the saturation

current, the parasitic series and shunt resistances, and the ideality factor. Among the proposed optimization

techniques, the differential evolution (DE) based method besides its computational advantage,

provides better accuracy compared to other methods. However, it is not an easy task to determine the

control parameters for the DE algorithm. This paper presents an improved adaptive DE (IADE) based optimization

technique. New formulas for the scaling factor and crossover rate are proposed. The proposed

IADE algorithm uses a simple structure based on the feedback of fitness value in the evolutionary process.

It provides better performance for estimation of the solar cell and module parameter values than other

popular optimization methods such as particle swarm optimization, genetic algorithm, conventional

DE, simulated annealing (SA), and a recently proposed analytical method. Comparisons with existing

methods for solar cell and module parameter estimation are presented using both synthetic and experimental

data under various environmental conditions. The proposed scheme offers higher accuracy, and

also eliminates the need for users to manually tune the control parameters of DE algorithm

چکیده : 

We prove the existence of a global nonnegative weak solution to the Cauchy problem of the

Vlasov–Poisson–BGK system for initial datum having finite mass and energy and belonging

to Lp(R3 × R3) with p > 3.

چکیده : 

Hydroelectric generation has the ability to buffer intermittent renewable generation. The objective of this

paper is to explore the changing roles of hydropower and pumped storage dispatch in response to

increasing renewable penetrations. A novel aggregate model of hydro resources in the state of California

is used in conjunction with the Holistic Grid Resource Integration and Deployment model (HiGRID), a

modeling tool that resolves hourly grid resource dispatch and management, to observe the impacts of

increasing renewable penetration. The effects on the grid are explored by incrementally increasing the

installed wind and solar capacity to meet the electric demand for California while re-dispatching hydro

energy and capacity resources to balance the electrical power system. Increasing renewable generation

results in increased periods of over generation, reducing the practical achievable renewable penetration.

By adjusting the dispatch of hydropower to complement renewable generation a significant increase in

the achievable renewable penetration can be implemented (8.0% for solar only, 2.2% for wind only and

2.8% for 50/50 mixture of wind and solar). Additionally, dispatching hydro to support renewables serves

to increase the system-wide capacity factor, delay the onset of curtailment, and reduce the total curtailment

at corresponding renewable penetrations

چکیده :

A mathematical programming model is proposed for the two parallel machines scheduling

problem where one machine is periodically unavailable, jobs are non-preemptive, and the

objective is minimizing the makespan. The model is established by transforming the two

parallel machine setting into a single machine setting. Average-case analyses of the classical

Longest Processing Time first (LPT) algorithm and the List Scheduling (LS) are presented.

Computational experiments show that the LPT algorithm beats the LS algorithm in all the

96 combinations of two main parameters from an average-case error point of view and that

the average-case error of the LPT algorithm is less than 2% when the number of jobs is

greater than twenty. Unexpectedly, there also exist instances showing that the LS algorithm

may beat the LPT algorithm from the average-case error point of view.

چکیده : 

Different ways to extract properties of excited states from time-dependent density functional theory (TDDFT)

calculations are compared to ab initio results obtained with the Equation of Motion Coupled Cluster

approach. The recently proposed a posteriori Tamm–Dancoff approximation (ATDA) predicts the permanent

dipole moments to be underestimated by 25% on average, close to the results of the relaxed density

TD-DFT formalism, quadratic response formalism, and numerical energy derivatives, while the unrelaxed

density approximation results are less accurate (40% overestimate). We also propose a correction for TDDFT

excitation energies, which are known to be problematic for charge transfer states. The static DFT

energies evaluated on the relaxed densities of the excited states are found to be more accurate than

TD-DFT excitation energies (RMSD is 0.7 eV vs. 1.1 eV, while maximum deviation is 1.0 eV vs.

2.0 eV). This validates ATDA for description of nonlinear optical properties of donor–acceptor molecules,

exemplified by para-nitroaniline, and extends this method to improve the excitation energy

predictions.

چکیده : 

A mixed implicit–explicit solvation approach has been used to calculate absolute aqueous pKa values for a

range of phenols using the economical and ubiquitous B3LYP/6-31+G model. Judicious positioning of two

water molecules around the phenol OH group and around the phenoxide O group, along with use of a simple

PCM implicit solvation model gives a good agreement between calculated and experimental values for

phenol acidity; this agreement is improved if a small (1.40 kcal mol1) correction factor is applied. This

approach offers a simple, rapid, and cost-efficient means of estimating aqueous pKa values for phenols.

چکیده : 

By carrying out density functional theory (DFT) calculations, we have performed a detailed mechanism

study on the Pt(II)-catalyzed tandem migration reactions of propargylic carboxylates. Our calculated

results suggest that the 1,2-H migration and 1,2-allyl migration are the key paths for the reaction of 4-

(allyloxy)-1,4-diphenylbut-2-ynyl acetate (1A), and the 1,2-H migration path is favored. For the reaction

of another reactant, the double 1,2-acyloxy migration path is suitable. Due to the steric factor, butenyl

migration is unfavored in the reactant of She’s experiment. Our computational results are in agreement

with the experimental findings of Liang et al. and She et al