1,489 research outputs found
MIDAS: Automated Approach to Design Microwave Integrated Inductors and Transformers on Silicon
The design of modern radiofrequency integrated circuits on silicon operating at microwave and millimeter-waves requires the integration of several spiral inductors and transformers that are not commonly available in the process design-kits of the technologies. In this work we present an auxiliary CAD tool for Microwave Inductor (and transformer) Design Automation on Silicon (MIDAS) that exploits commercial simulators and allows the implementation of an automatic design flow, including three-dimensional layout editing and electromagnetic simulations. In detail, MIDAS allows the designer to derive a preliminary sizing of the inductor (transformer) on the bases of the design entries (specifications). It draws the inductor (transformer) layers for the specific process design kit, including vias and underpasses, with or without patterned ground shield, and launches the electromagnetic simulations, achieving effective design automation with respect to the traditional design flow for RFICs. With the present software suite the complete design time is reduced significantly (typically 1 hour on a PC based on IntelÂź PentiumÂź Dual 1.80GHz CPU with 2-GB RAM). Afterwards both the device equivalent circuit and the layout are ready to be imported in the Cadence environment
Characterization of CMOS Spiral Inductors
In this work "full-wave" simulations of integrated inductors are presented and compared with measurements of fabricated CMOS chips. The good agreement between measurements and simulations demonstrates the accuracy of the tool, which is, hence, a cheaper alternative to experimental characterization. Furthermore, the proposed approach may give precious hints for performance improvements, by making internal device fields and currents available for the VLSI designer and providing compact, most effective, equivalent models
Wind farms, farmland occupation and compensation: Evidences from landownersâ preferences through a stated choice survey in Italy
The willingness to accept the construction of wind farms on private properties is investigated using a latent class model approach. This type of research is required in view of the frequent conflicts between landowners and system operators, who often pay little in easement compensation. This study highlights the fact that the acceptance of wind farms is a multifaceted issue comprising aspects relating to socioeconomics, farm type, territory, and past experience. In particular, the compensation claimed by landowners depends on the property's size, the number of turbines, the crop, the presence of surrounding wind farms, natural impacts, the landscape configuration, land fragmentation, land agreements, the presence of other wind towers on the property, and past experience with system operators concerning transparency and participation in the siting and planning phases. Stakeholders should take these factors into account to develop energy policies based on clear, and well-structured processes concerning the siting, planning, construction, and management of wind farms, in order to prevent conflict and to benefit the community and environment
Superconductor Microwave Kinetic Inductance Detectors: System Model of the Readout Electronics
This paper deals with the readout electronics needed by superconductor Microwave Kinetic Inductance Detectors (MKIDs). MKIDs are typically implemented in the form of cryogenic-cooled high quality factor microwave resonator. The natural frequency of these resonators changes as a millimeter or sub-millimeter wave radiation impinges on the resonator itself. A quantitative system model of the readout electronics (very similar to that of a vector network analyzer) has been implemented under ADS environment and tested by several simulation experiments. The developed model is a tool to further optimize the readout electronic and to design the frequency allocation of parallel-connected MKIDs resonators. The applications of MKIDs will be in microwave and millimeter-wave radiometric imaging as well as in radio-astronomy focal plane arrays
Phytoplankton composition in the coastal Magnetic Island lagoon, Western Pacific Ocean (Australia)
1 - Coastal lagoons have traditionally been considered as transitional systems between continental and marine domains. The phytoplankton plays a key role in these aquatic environments, forming the base of the food web and having a substantial function in nutrient dynamics and in the carbon biogeochemical cycle.2 - Due to their short life cycle, planktonic algae respond quickly to environmental changes and they are thus a valuable indicator of water quality. It is essential to investigate the development of phytoplankton populations to understand the biological functioning and to detect changes in aquatic systems.3 - Phytoplankton studies in the Australian estuaries and lagoons are relatively scarce. This study has provided a broad perspective and preliminary information on taxonomic structure of phytoplankton guilds for the Magnetic Island Lagoon (Queensland, Australia). This work may provide valuable information of interest to later ecological studies.4 - In the whole sampling a total of 143 taxa were identified. In terms of species richness, diatoms (Bacillariophyceae, Coscinodiscophyceae, Fragilariophyceae) and dinoflagellates (Dinophyceae) were the most important groups. In taxonomic terms, diatoms were the major contributor to the phytoplankton composition (~ 70%) whereas Dinophyceae were moderately abundant (~23%). Diatoms are a very important component in estuarine and shallow coastal wetlands and they are increasingly being utilized as indicators of environmental change
EH Performance of an Hybrid Energy Harvester for Autonomous Nodes
This paper reports the Energy Harvesting (EH) performance of a hybrid energy harvester able to collect energy form different energy sources: thermal, solar and electromagnetic. The main block of the system is the quarter-wavelength patch antenna, operating in the Industrial, Scientific and Medical (ISM) frequency band 2.4-2.5 GHz. The antenna has been designed and optimized to support a Thermo-Electric Generator (TEG) and a Solar Cell on its top. Moreover, a rectifier has been designed to work with the antenna and a DC-DC converter has been used to manage the TEG output voltage
Feedup, feedback, and feedforward in curve mid-air 3D gestures
Issuing a mid-air gesture in a three-dimensional space intrinsically suffers for the lack of explicit direct representation of the gesture with which guidance and feedback can be offered. To address this challenge, we decompose the feedback problem into three components: feedup to constantly represent the goal of the gestural task, feedback to respond to what the end user already did related to the initial goal, and feedforward to modify the representation towards the ultimate goal before terminating the gesture production. We exemplify these three components with case studies representing three levels of complexity of Curve Mid-Air 3D Gestures produced in three environments
Acquatina Lagoon: a model ecosystem to study community patterns
Acquatina is a small lagoon ecosystem (0.45 km2) located on the Adriatic coast only 5 km north
of Lecce (Italy). The lagoon has a freshwater input in the northern part and a connection with
the sea at the south edge, being characterised by a latitudinal gradient of salinity and an internal
patchiness of habitats. Here, we have used the lagoons as a model to study the influence of
these sources of variation on the spatial distribution of macrobenthis and fish fauna, using both
taxonomic and on taxonomic descriptors. Results showed a non random distribution of both species and functional traits of macroinvertebrate
and fish fauna within the lagoon, despite the relatively small surface area. Salinity had an higher inflence than boItom habitat patchiness on both macroinvertebrates and fishes; moreover, spatial co-variance of the two guilds was observed both at the taxonomic and at the size level. As regards
fishes, these patterns were common to the dominant species (Atherina Boyeri) and to the rest of the fish guild.
Results emphasise that common non random distribution patterns are observed even in small lagoons and for different guilds, including vagile fauna, as fish are. It suggest the occurrence of high intra-specific and inter-specific divergence in lagoon ecosystem allowing resource use
optimisation through niche specialisation, available energy partitioning and individual energy budget adaptation
A dimensional approach to the psychopathology of migrants: a cross-sectional matched sample study
Objectives
Moving to a foreign country, whether out of necessity, seeking refuge, opportunity or mere curiosity, makes the individual more vulnerable to mental disorders. Even in the same conditions, many factors contribute to make migrants more susceptible to this risk than the
natives. Among many, these include linguistic and cultural differences. Unfortunately, these differences lead to a higher frequency of ânot otherwise specifiedâ diagnoses in this part of the population. This limitation can lead to greater difficulties in therapeutic choices and epidemiological assessments. This study aims to enhance the clinicianâs resources by testing a
trans-diagnostic, dimensional, psychopathological approach in the assessment of a group of migrants and a control group of natives referred to a psychiatric outpatient service.
Methods
The two groups of patients were matched for gender, age, categorical diagnosis and level of clinical severity. The SVARAD scale was used for the dimensional assessment, diagnoses were assigned according to DSM IV-TR criteria.
Results
A total of n = 224 patients, including cases (n = 112) and controls (n = 112), were recruited and agreed to participate in the study. The dimensions somatization, obsessiveness, and activation showed a significant difference between groups (p = .018; .011; .004, respectively).
Given the same degree of severity and the same diagnosis, migrants with mental disorders showed less activation and greater somatization.
Conclusions
Cross-cultural aspects and language differences, as well as the same social status of âmigrantâ, are certainly implicated in these differences. By taking these dimensional aspects into
account, clinicians could achieve greater precision in the diagnostic process and determine a significant change in the care of this risk group
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