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This paper investigates the impact of various codecs and coding parameters on power consumption of video decoding on mobile handheld devices. With limited battery capabilities of mobile device and with current trend of an increased demand on quality of video contents the power management becomes the vital aspect for mobile devices. Besides the decoding complexity, the file size of the investigated codecs is also taken into account. By using SSIM (Structural SIMilarity index) metric, the measured results for power consumption and storage demand are correlated with perceived video quality.

The paper describes Asynchronous Sigma-Delta Modulator Analog-to-Digital Converter (ASD-ADC) built around the first order ASD modulator. Asynchronous sigma-delta modulator performs asynchronous amplitude-to-time conversion creating 1-bit output sequence which is further sampled by the Time-to-Digital Converter (TDC) and converted into the time-discrete synchronous m-bit words, suitable for further digital signal processing. Proposed ASD-ADC architecture, simulation of its MATLAB madel and evaluation of its performances are described.

This paper presents a modified Cockcroft-Walton charge pump designed for driving capacitive or low current resistive loads. The proposed modification by using switched capacitors technique shows great improvement in output voltage levels that it achieves, and in number of capacitors needed for reaching a certain voltage level. Also, it requires no additional clocking scheme besides the present single phase AC signal. The proposed Switched Cockcroft-Walton (SCW) charge pump was simulated and compared with the CW charge pump.

This paper presents an ID tag concept which is LED powered. The photovoltaic effect of the LED array is used to harvest energy from ambient light or from light source in reader device in order to power the tag. Harvested energy is stored in a capacitor that is used to supply ID tag logic which transmits ID information using one diode of LED array which is also used for powering. The powering circuit, i.e. LED energy harvester is tested for various commercially available LEDs, to determine the most suitable LED type with respect voltage gain and current drivability. The power consumption of presented LED ID tag is optimized using Response Surface Methodology with respect to the following input parameters: frequency of operation, frequency of data transmission and the data packet length with respect to the consumed power and the transmission distance. The optimization proposes optimal input parameters for minimum power consumption and maximum operating distance, presenting a compromise between the aforementioned parameters in reference to the input variables.

Permanent ponds represent important habitats for aquatic biodiversity and provide vital ecosystem services as key elements for blue landscape connectivity. Although mostly neglected in management programmes, protection schemes and biodiversity studies in general, ponds constitute habitats with high á- and spatial â-diversity, providing unique habitat conditions for many rare and endemic species. The main focus of our contribution is to describe Odonata (including both dragonflies and damselflies) diversity patterns from 46 ponds distributed across Europe. Our data set summarises all Odonate occurrences (i.e., Odonata captured in emerging traps, adults recorded in the surrounding environment and larvae from benthic samples) from the EUROPONDS project - an Early Career Researchers (ECR) project focusing on emerging insects from ponds. Field sampling was conducted during a whole year sampling campaign throughout 2020/21 in 18 European countries. Our preliminary results suggest a clear latitudinal gradient in Odonata diversity across Europe, i.e., the highest α- and β-diversity levels were found in southernmost ponds (Spain) and the lowest diversity in northernmost ponds (Ireland). Odonata that belonged to the four families of Aeshnidae, Libellulidae, Coenagrionidae and Platycnemididae were captured in the emergence traps in only nine out of the total 46 sampled ponds. The most diverse family was Coenagrionidae, which also represented the most abundant odonate family in benthic samples, especially noted in Polish ponds. Among the observed adult specimens of Odonata (42 different taxa), the commonest species across Europe were Sympetrum striolatum, Aeshna cyanea, Anax imperator, Libellula quadrimaculata, Crocothemis erythraea and Enallagma cyathigerum. Additionally, the endemic species Ischnura graellsii and the newly immigrant Trithemis kirbyi were reported from Spanish ponds. These locations constitute their northernmost distributional ranges in Europe. Overall, our findings should contribute to the knowledge on spatial distributions of odonates across European ponds.

Whilst being small and shallow, permanent ponds provide valuable habitats for a multitude of organisms as well as provide habitats for animals like aquatic insects and others, including many rare species. These ponds, which were often neglected in limnological studies, were the core of our joint project, the 3rd freshwater project - EUROPONDS in order to evaluate the often overlooked ecological ecosystem services provided by permanent ponds across Europe. As a part of this project, two Hungarian ponds were surveyed for a full year (2020/21). One of the project aims was to assess the freshwater macroinvertebrate assemblages by dip netting over the four annual seasons. Here, we present preliminary results examining the data on larval Odonata of two Hungarian ponds in relation to the physicochemical variables measured, as well as compare the results to a previous national survey. Altogether the examination of 24 waterbodies (22 from a national survey and two from the EUROPONDS project) was carried out in this study. All of the involved water bodies were clustered using a Ward analysis including the water physicochemical parameters into three groups, and then the dragonfly fauna was investigated within the groups found. Diversity metrics and the presence or absence of different species were also included and the results were compared between the different clusters. Herein, we aimed to assess differences between the three main clusters, identify key factors driving the presence of the studied species and the relationship between the diversity indexes and the physicochemical parameters influencing the Odonata communities in the studied ponds.