A convenient and efficient one-step method for the synthesis of dicompartmental ligands with hexa- and tetradentate coordination sites

A convenient and more efficient method for the preparation of 1,6-bis(2-pyridyl)-2,5-bis(2-hydroxy-3-formyl-5-methyl benzyl)-2,5-diazahexane, L1H2 and 1,7-bis(2-pyridyl)-2,6-bis(2-hydroxy-3-formyl-5-methyl benzyl)-2,6-diazaheptane, L2H2 are described. The ligands were prepared by reaction of two moles of 3-(chloromethyl)-2-hydroxy-5-methyl benzaldehyde with a mole of N,N'-bis(2-pyridyl)dopamine in THF at ambient conditions in high yield (75-80%).KEY WORDS: Dicompartmental ligand, Synthesis, Phenol-based ligand, Acyclic ligandBull. Chem. Soc. Ethiop. 2010, 24(1), 151-155

Real-time Energy Management of a Battery Electric Vehicle Hybridized with Supercapacitor

The increased interest in electric vehicles (EVs) in the recent years has intrigued numerous research, on improving efficiency and reducing ownership costs of these vehicles. As the battery in EVs is the sole energy provider, it is exposed to degradation due to high peaks and rapid fluctuations in the power demanded by the driver. Therefore, integrating a supercapacitor (SC) pack into the energy storage system of these vehicles has been proposed as a potential solution; maintaining the battery as the main energy source of the vehicle while using the SC when exposed to high power peaks and power fluctuations. However, just like any other hybrid system, the maximum benefit of this integration can only be exploited when applying a proper energy management controller. Various energy management controllers have been used for these systems through the literature; ranging from simple rule based control strategies to more complex optimal control approaches. In this thesis, nonlinear model predictive control (NMPC) strategies have been designed as energy management controllers for battery-SC hybrid energy storage systems (HESSs) in a Toyota Rav4EV. Although traditionally used in applications dealing with slow dynamics like process control, with the rapid improvement in electric control units (ECUs) in the recent years, NMPCs have received a great deal of attention in areas with systems of faster dynamics, including the automotive sector. However, the question still needs to be addressed whether NMPC can demonstrate performance improvement over other state-of-the-art controllers, while maintaining computational efficiency necessary for automotive real-time applications. This investigation has been conducted through Model-in-the-Loop (MIL) simulating and Hardware-in-the-Loop (HIL) testing on the NMPC energy management strategies designed in this work. The NMPC uses a control-oriented model of the system, some form of the future trip prediction, and an optimization solver to find the optimal power split between the battery and SC at each time step during the trip. The designed NMPC has been compared to other state-of-the-art controllers in the literature. A number of methods for future trip prediction have also been studied through the thesis and the NMPC shows to outperform other controllers even with no prior knowledge of the future trip whatsoever. The results obtained through HIL testing on a dSPACE ECU indicate that upon carefully choosing the prediction and control horizon length, as well as the maximum number of iterations allowed, the execution time for NMPC falls far below the necessary sampling time of 10 milliseconds in vehicle control. The correlation between each of these parameters and turn-around time have been presented; constructing a benchmark for NMPC design

Synthesis and characterization of mono- and bimetallic complexes of Zn(II) and Cu(II); new multifunctional unsymmetrical acyclic and macrocyclic phenol-based ligand

The dicompartmental macrocyclic ligand (L2)2- was prepared by [1:1] cyclic condensation of N,N′-dimethyacetate-N,N′-ethylene-di(5-methyl-3-formyl-2-hydroxybenzylamine with 1,3-diaminopropane. The ligand includes dissimilar N(amine)2O2 and N(imine)2O2 coordination sites sharing two phenolic oxygen atoms and containing two methyl acetate pedant arms on the amine nitrogen donor atoms. A series of mono- and bimetallic complexes were synthesized and characterized on the basis of elemental analysis, molar conductance measurement, IR and UV-Vis spectroscopy techniques. It was found that during the cyclization process the copper (II) displaced from the N(amine)2O2 to the N(imine)2O2 coordination site and one of the methyl acetate pedant arms is dissociated. The heterodinuclear complex of [ZnL2Cu(-OAc)]+ was prepared by a transmetallation reaction on the [ZnL2Zn(-OAc)]+ by Cu(II). The characterization results showed that the two metal ions are bridged by two phenolic oxygen atoms and an acetate group, providing distorted five-coordination geometries for the both metal ions

Polar Collision Grids: Effective Interaction Modelling for Pedestrian Trajectory Prediction in Shared Space Using Collision Checks

Predicting pedestrians' trajectories is a crucial capability for autonomous vehicles' safe navigation, especially in spaces shared with pedestrians. Pedestrian motion in shared spaces is influenced by both the presence of vehicles and other pedestrians. Therefore, effectively modelling both pedestrian-pedestrian and pedestrian-vehicle interactions can increase the accuracy of the pedestrian trajectory prediction models. Despite the huge literature on ways to encode the effect of interacting agents on a pedestrian's predicted trajectory using deep-learning models, limited effort has been put into the effective selection of interacting agents. In the majority of cases, the interaction features used are mainly based on relative distances while paying less attention to the effect of the velocity and approaching direction in the interaction formulation. In this paper, we propose a heuristic-based process of selecting the interacting agents based on collision risk calculation. Focusing on interactions of potentially colliding agents with a target pedestrian, we propose the use of time-to-collision and the approach direction angle of two agents for encoding the interaction effect. This is done by introducing a novel polar collision grid map. Our results have shown predicted trajectories closer to the ground truth compared to existing methods (used as a baseline) on the HBS dataset.Comment: Accepted for publication as a conference paper in IEEE Intelligent Transportation Systems Conference (ITSC), 202

Pedestrian Trajectory Prediction in Pedestrian-Vehicle Mixed Environments: A Systematic Review

Planning an autonomous vehicle's (AV) path in a space shared with pedestrians requires reasoning about pedestrians' future trajectories. A practical pedestrian trajectory prediction algorithm for the use of AVs needs to consider the effect of the vehicle's interactions with the pedestrians on pedestrians' future motion behaviours. In this regard, this paper systematically reviews different methods proposed in the literature for modelling pedestrian trajectory prediction in presence of vehicles that can be applied for unstructured environments. This paper also investigates specific considerations for pedestrian-vehicle interaction (compared with pedestrian-pedestrian interaction) and reviews how different variables such as prediction uncertainties and behavioural differences are accounted for in the previously proposed prediction models. PRISMA guidelines were followed. Articles that did not consider vehicle and pedestrian interactions or actual trajectories, and articles that only focused on road crossing were excluded. A total of 1260 unique peer-reviewed articles from ACM Digital Library, IEEE Xplore, and Scopus databases were identified in the search. 64 articles were included in the final review as they met the inclusion and exclusion criteria. An overview of datasets containing trajectory data of both pedestrians and vehicles used by the reviewed papers has been provided. Research gaps and directions for future work, such as having more effective definition of interacting agents in deep learning methods and the need for gathering more datasets of mixed traffic in unstructured environments are discussed.Comment: Published in IEEE Transactions on Intelligent Transportation System

REEP3 and REEP4 determine the tubular morphology of the endoplasmic reticulum during mitosis

The endoplasmic reticulum (ER) is extensively remodeled during metazoan open mitosis. However, whether the ER becomes more tubular or more cisternal during mitosis is controversial, and dedicated factors governing the morphology of the mitotic ER have remained elusive. Here, we describe the ER membrane proteins REEP3 and REEP4 as major determinants of ER morphology in metaphase cells. REEP3/4 are specifically required for generating the high-curvature morphology of mitotic ER and promote ER tubulation through their reticulon homology domains (RHDs). This ER-shaping activity of REEP3/4 is distinct from their previously described function to clear ER from metaphase chromatin. We further show that related REEP proteins do not contribute to mitotic ER shaping and provide evidence that the REEP3/4 carboxyterminus mediates regulation of the proteins. These findings confirm that ER converts to higher curvature during mitosis, identify REEP3/4 as specific and crucial morphogenic factors mediating ER tubulation during mitosis, and define the first cell cycle-specific role for RHD proteins.Peer reviewe

Crystal structure of an eight-coordinate terbium(III) ion chelated by N,N′-bis­­(2-hy­dr­oxy­benz­yl)-N,N′-bis­­(pyridin-2-ylmeth­yl)ethyl­enedi­amine (bbpen2−) and nitrate

The reaction of terbium(III) nitrate pentahydrate in acetonitrile with N,N′-bis(2-hydroxybenzyl)-N,N′-bis(pyridin-2-ylmethyl)ethylenediamine (H2bbpen), previously deprotonated with triethylamine, produced the mononuclear compound [N,N′-bis(2-oxidobenzyl-κO)-N,N′-bis(pyridin-2-ylmethyl-κN)ethylenediamine-κ2N,N′](nitrato-κ2O,O′)terbium(III), [Tb(C28H28N4O2)(NO3)]. The molecule lies on a twofold rotation axis and the TbIII ion is eight-coordinate with a slightly distorted dodecahedral coordination geometry. In the symmetry-unique part of the molecule, the pyridine and benzene rings are both essentially planar and form a dihedral angle of 61.42 (7)°. In the molecular structure, the N4O4 coordination environment is defined by the hexadentate bbpen ligand and the bidentate nitrate anion. In the crystal, a weak C—H...O hydrogen bond links molecules into a two-dimensional network parallel to (001)