One-dimensional particle-in-cell Monte Carlo collision (PIC-MCC) simulations of low-pressure (10 mTorr) argon plasmas sustained by a triple-frequency (1, 30 and 120 MHz) source in symmetrical current-driven and voltage-driven capacitively coupled plasma reactors are carried out. We concluded that the effective current, the effective voltage and the effective frequency are helpful in explaining the physics of triple-frequency capacitively coupled plasma sources (CCPs) alike single-frequency CCPs. The rf discharge parameters such as the ion energy distribution function (IEDF), the sheath length, the plasma potential and the powers dissipated by electrons and ions can be expressed as the effective frequency and the effective current density (or effective voltage). The analytical model of the IEDF for triple-frequency CCPs in the high-frequency regime is developed. The analytical calculations of the IEDF in the high-frequency regime through the effective frequency visualized in this paper are compared with the simulation results of the IEDF calculated from the 1D PIC-MCC model. The ion energy width and the average ion energy of the IEDF are controlled by the effective frequency, which is expressed as a function of the current density (or voltage) and frequency ratios of the triple-frequency source. The evolution of the effective frequency with the current density or voltage ratio of three frequency sources is different depending on the mode of operating source, which is either voltage or current. The effective frequency in voltage-driven CCPs is 2-10 times higher than that of current-driven CCPs at the same ratio of current density and voltage. As a result, the current-driven CCPs is more desirable than the voltage-driven CCPs from the aspect of independent control of ion flux and ion bombardment energy because the ion energy width increases with decreasing effective frequency.

A multiobjective dynamic vehicle routing problem (M-DVRP) has been identified and a time seed based solution using particle swarm optimization (TS-PSO) for M-DVRP has been proposed. M-DVRP considers five objectives, namely, geographical ranking of the request, customer ranking, service time, expected reachability time, and satisfaction level of the customers. The multiobjective function of M-DVRP has four components, namely, number of vehicles, expected reachability time, and profit and satisfaction level. Three constraints of the objective function are vehicle, capacity, and reachability. In TS-PSO, first of all, the problem is partitioned into smaller size DVRPs. Secondly, the time horizon of each smaller size DVRP is divided into time seeds and the problem is solved in each time seed using particle swarm optimization. The proposed solution has been simulated in ns-2 considering real road network of New Delhi, India, and results are compared with those obtained from genetic algorithm (GA) simulations. The comparison confirms that TS-PSO optimizes the multiobjective function of the identified problem better than what is offered by GA solution.

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The advances in electrotherapy to treat the diseased biological cell instigate its extension in gene therapy through the delivery of gene into the nucleus. The objective of this study is to investigate the application of moderate intensity alternating electric field, also known as tumor treating electric field on a carrier system consisting of a charged gene complex conjugated to the surface of a gold nanoparticle. The gene delivery mechanism relies on the magnitude and direction of the induced electric field inside the cytoplasm in presence of carrier system. The induced electric field strength is significant in breaking the gene complex-gold nanoparticle bonding, and exerting an electric force pushing the charged gene into the nucleus. The electric force orientation is dependent on the aspect ratio (AR) of the gold nanoparticle and a relationship between them is studied via Maxwell two-dimensional (2D) finite element simulation analyzer. The development of charge density on the surface of carrier system and the required electric field strength to break the bonding are investigated utilizing the Gouy-Chapman-Grahame-Stern (GCGS) theoretical model. A carrier system having the aspect ratio of the gold nanoparticle in the range 1 < AR ≤ 5 and AR = 1 are substantial delivering cationic and anionic genes into the nucleus, respectively.