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The power electronic converter is used for the satisfaction of reactive power demand of induction generator, when grid-tied. This paper aims to present an application of STATCOM to reduce inrush transient caused by the connection of a squirrel-cage induction generator (SCIG) to the grid.

The power generation system consists of an uncontrolled prime mover, a SCIG and a power electronic converter connected to the grid. The three-phase Neutral Point Clamped (NPC) converter works as a STATCOM to satisfy a reactive power demand of the generator. A control scheme of STATCOM uses the x-y reference frame rotating synchronously with grid voltage vector and the p-q instantaneous power theory to calculate q component of grid power.

It is shown that the parallel converter, which works as a reactive power compensator allows decreasing transients during a grid connection of the induction generator.

Transients during a grid connection of the induction generator are only partially decreased.

It is needed to compensate for the reactive power of a SCIG. The NPC converter works as a STATCOM. The converter partially reduces grid transients during generator connection. The laboratory tests are demonstrated by connection 7.5 kW induction generator to 8 kVA transformer.

The paper presents the mitigation of grid transients during connection of induction generator with the power electronic converter working as reactive power compensator.

My name is Andrzej Gorski and I am one of the directors of the Pewex company. I don't have to explain to Polish people what the company is, but for the benefit of people who are in Poland for the first time, I'll explain something of the company.

Because of the bioaccumulation effect, organophosphorus pesticides cause long-term damage to mammals, even at small concentrations. The ability to perturb the phospholipid bilayer structure as well as the overstimulation of cholinergic receptors makes them hazardous to humans. Therefore, there is a need for a quick and inexpensive detection of organophosphorus pesticides for agricultural and household use. As organophosphorus pesticides are acetylcholinesterase (AChE) inhibitors, biosensors using this mechanism hold a great promise to meet these requirements with a fraction of reagents and time used for measurement comparing to laboratory methods. This study aims to manufacture AChE-coated, screen-printed carbon electrodes applicable in such amperometric biosensors.

AChE enzyme, known for catalytic activity for the hydrolysis of acetylthiocholine (ATCh), could be used to obtain electrochemically active thiocholine from acetylthiocholine chloride in aqueous solutions. Using Malathion’s inhibitory effect towards AChE, pesticides’ presence can be detected by reduction of anodic oxidation peaks of thiocholine in cyclic voltammetry.

The conducted research proved that it is possible to detect pesticides using low-cost, simple-to-manufacture screen-printed graphite (GR) electrodes with an enzymatic (AChE) coating. Investigated electrodes displayed significant catalytic activity to the hydrolysis of ATCh. Owing to inhibition effect of the enzyme, amperometric response of the samples decreased in pesticide-spiked solution, allowing determination of organophosphorus pesticides.

Printed electronics has grown significantly in recent years as well as research focused on carbon-based nanocomposites. Yet, the utilization of carbon nanocomposites in screen-printed electronics is still considered a novelty in the market. Biosensors have proved useful not only in laboratory conditions but also in home applications, as glucometers are a superior solution for glucose determination for personal use. Although pesticides could be detected accurately using chromatography, spectroscopy, spectrometry or spectrophotometry, the market lacks low-cost, disposable solutions for pesticide detection applicable for household use. With biosensing techniques and electric paths screen-printed with GR or graphene nanocomposites, this preliminary research focuses on meeting these needs.

I would like to ask a question first to Mr Ian Day and later on to the gentlemen representing the project KAREN‐PEWEX.

The aim of this paper was to verify applicability of graphene-based sensors for voltammetric and amperometric measurements of low-concentration compounds in biological fluids.

Using the screen printing method, electrochemical sensors were manufactured on polymethylmetacrylate foil using a paste consisting of organic solvents and graphene nanopetals. As the model of a biological fluid tear film was chosen, the compound chosen as the analyte was H₂O₂, which is produced in oxidation of biological compounds. Tear film analog was prepared, in which, the measurements were carried out in a wide range of concentrations to determine the oxidation potential of H₂O₂ through square-wave voltammetry. The second series of amperometric measurements was carried out for concentrations between 0 and 30 μM/L, which is the lower range of physiological glucose concentration in tear films.

The sensors presented linearity for concentrations from 0 to 3.5 per cent. Mean linear correlation coefficient between the peak current and the concentration for the examined sensors was 0.9764. Mean sensitivity was 434.4 mA·M−1·L−1.

Results indicate a need for optimization of the sensors ' performance. Main parameters to be improved are surface area of electrodes and purity of the graphene layer, as well as uniformity of the manufacturing process to improve accuracy and repeatability of measurements.

Technology and materials used present an opportunity for creating low-cost, miniaturized and biocompatible sensors to be used in medical monitoring.

Printed electronics technology described was not investigated previously in the field of biological sensors and could contribute to the solving of vital medicine problems.

The purpose of this paper is to develop a framework that systematically captures the ambiguity of different understandings about science, the university and its relation to society, while conceptualising sustainability. Following Corley and Gioia (2004, p. 174) on identity ambiguity and change, it seems pivotal to better understanding the ambiguity of sustainability in relation to academic cultures and university models to manage the transition more effectively.

The nature of this paper’s objectives as well as the wide thematic scope leads to the need of exploring a broad knowledge base. This was best addressed by an exploratory literature review with data collection from primary and secondary sources. The data was interpreted through a hermeneutic analysis and resulted in the inductive development of first categories and goals (further referred to as category development). In addition, a multi-method approach further adjusted the categories and raised their empirical validity and social robustness.

Implementing sustainability involves dealing with a double bound ambiguity due to organisational and individual identity reasons. Five fields of ambiguity were developed to systemise the conceptualisation of a sustainable university along contradictory understandings of science, the university and sustainability. These fields offer a framework to qualitatively assess the degree of sustainability in higher education institutions. Arguments for and against sustainability in universities have been categorised around five criteria and associated to the fields of ambiguity. The finding indicates that meaning in organisational change management for sustainability can be considered both, a potential driver and barrier for a sustainability transition in universities.

This paper exclusively focussed on the internal perspective and left aside any external factors that influence the sustainability transition, such as political measures to stimulate sustainability in higher education. In addition, the operational dimension of a sustainable university has been neglected, which is by all means a necessary and important aspect. The interrelation of the identified goals has not been discussed.

This paper focusses on the conceptualisation and understanding of sustainability within the institution, an often-forgotten but fundamental aspect of implementation. The fields of ambiguity are designed to be applied for assessing the “degree of maturity” of a sustainable university. The fields reveal the different understandings about the role, the mission and the governance of universities, stemming from competing preferences about goals and their assumed relations by various stakeholders of a higher education institutions. The five fields are not an attempt to resolve the hidden contradictions and tensions in a sustainability transition, but to state them clearly to anticipate resistances and conflicts that hinder the development of a shared understanding.