Kyriakos Almpanidis

Three-dimensional electrospun foams are emerging in a diversity of applications. However, their characterisation involves procedures to calculate fibre diameter and porosity, which take considerable time. Hence, in this paper, an in situ characterisation method is presented based on signal features of the grounding voltage. These features are combined into the in situ evaluation parameter Sr for each run r. The L9 Taguchi method was utilised to minimise the total number of experiments. Moreover, to prove the accuracy of this method, the traditional post-fabrication analysis was conducted, and the post-fabrication evaluation parameter was retrieved Qr for each run r. The analysis shows that both parameters detected the same experiment run as the optimal one (with an adjusted R2 = 0.84) for polystyrene electrospun foams for two solution concentrations: 15%wv (run 3 with mean S3 = 54.49 and mean Q3 = 0.248) and 20%wv (mean S5 = 2.49 and Q5 = 0.248), respectively. Also, the statistical analysis shows low standard deviations for the optimal and near-optimal runs, proving the method’s repeatability. Furthermore, a theoretical explanation is provided for selecting signal features based on the Maxwellian equivalent circuit approach for the electrospun jet. Finally, this fast in situ evaluation method can replace the post-fabrication time-consuming one. It can be used as a fundamental step for an intelligent artificial intelligence tool that predicts optimal foam formation.

The application of ultraviolet ozone (UV-Ozone) treatment of thermally evaporated molybdenum oxide (MoOx) as a hole transport layer (HTL) in non-fullerene acceptor (NFA)-organic solar cells (OSCs) has markedly improved the charge carrier transport. As a result, we report the power conversion efficiency (PCE) of PM6:Y6-based OSCs has been improved from 14.26% for pristine to 15.06% for UV-Ozone-treated devices. This PCE enhancement is attributed to increased hole mobility, more balanced mobilities ratio and higher direct current (DC) conductivity. Additionally, the formation of a more favourable interface between MoOx and the PM6:Y6 due to the UV-Ozone exposure, resulted in longer charge carrier lifetimes. Light soaking experiments at 55 degrees C in a nitrogen environment demonstrated superior operational stability with pristine and UV-Ozone-treated MoOx, retaining 58% and 65% of their initial PCE after 100 hours, respectively. This stands in contrast to devices based on PEDOT:PSS that deteriorated to 23% of their initial PCE after half the time period. This strategy is an enabler towards simultaneous improvement in performance and stability compared to the control PEDOT:PSS-based cells, presenting high efficiency but significantly lower lifetime stability. The broad applicability of UV-Ozone treatment of thermally evaporated MoOx HTLs was further validated through the fabrication of OSCs with a PM6:L8-BO photoactive layer, achieving a peak PCE value of 16.85%. These findings indicate significant advancements in the use of transition metal oxides in NFA-based OSCs and highlight the potential for new device architectures for organic electronics.

In robotic assisted surgeries, surgical tools are inserted into the human body via an incision point in the abdominal wall, which is imposed as a remote center of motion (RCM). The selection of the incision's point location in the human body is critical for the success of the surgical procedure. In this paper, we propose a simulation tool for finding the optimal incision point location, which can be utilized by the surgeon during the preoperative stage. The surgeon can plan the path/region of intervention as well as sensitive regions which should be protected from unintentional damage by the surgical tool on the preoperative images of internal organs. A target admittance model that enforces a candidate incision as a RCM is utilized in the simulation enhanced by a term for following the planned path. We propose a cost evaluation function taking into account metrics involving the distance of the tool from sensitive areas, the tool links maximum pressure on tumors and the robot's dexterity measure. The example of a tumor resection task is used with the simulation tool to demonstrate its use in finding the incision points that ensures minimal intraoperative risks and accurate task execution.