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Global Optimization of Microwave Filters Based on a Surrogate Model Assisted Evolutionary Algorithm
Get PDFLocal optimization is a routine approach for full-wave optimization of microwave filters. For filter optimization problems with numerous local optima or where the initial design is not near to the optimal region, the success rate of the routine method may not be high. Traditional global optimization techniques have a high success rate for such problems, but are often prohibitively computationally expensive considering the cost of full-wave electromagnetic simulations. To address the above challenge, a new method, called surrogate model-assisted evolutionary algorithm for filter optimization (SMEAFO), is proposed. In SMEAFO, considering the characteristics of filter design landscapes, Gaussian process surrogate modeling, differential evolution operators, and Gaussian local search are organized in a particular way to balance the exploration ability and the surrogate model quality, so as to obtain high-quality results in an efficient manner. The performance of SMEAFO is demonstrated by two real-world design cases (a waveguide filter and a microstrip filter), which do not appear to be solvable by popular local optimization techniques. Experiments show that SMEAFO obtains high-quality designs comparable with global optimization techniques but within a reasonable amount of time. Moreover, SMEAFO is not restricted by certain types of filters or responses. The SMEAFO-based filter design optimization tool can be downloaded from http://fde.cadescenter.com
Implementation of brute force algorithm for topology optimisation of wireless networks
Get PDFThe paper discusses the topology optimisation of wireless networks using a brute force algorithm. In order to reduce the computational complexity of the algorithm the multi-thread application has been implemented to conduct the optimisation procedure. The efficiency of the algorithm was verified using an example task where topology of a wireless network has been optimised under various criteria
Mystical orientation and psychological health: a study among university students in Turkey
Get PDFThis study examines the association between mystical experience, as captured by the Francis–Louden Mystical Orientation Scale, and psychological health, as captured by the Eysenckian three-dimensional model of personality, among 329 students attending a state university in Turkey. The data reported no significant association between mystical orientation and psychoticism scores, and a small but significant positive association between mystical orientation and neuroticism scores, after controlling for sex differences. This finding suggests that there may be a small inverse association between mystical experience and psychological health among students in Turkey
Body Area Networks in a Medical Environment
Get PDFThere has been a great deal of development in the area of fitness / Activity Trackers which are now capable of measuring many useful human conditions e.g. heart rate. This paper investigates if the technology is suitable for use in a medical environment and in particular what systems would need to be introduced to supports it. The concept of an Intelligent Bed is introduced and a possible solution is provided. Due to the deployment in sensitive areas the issues of performance and reliability are addressed
Data Analysis of Random Blood Measurements for Abnormal Condition Detection
Get PDFThis paper discusses an approach of the abnormal condition detection of whole blood using piezo-synthetic effects in blood under dynamic external pressure. Three groups of samples having verified chemical and biological conditions were analysed to prove reliable detection: saline, whole blood and whole blood with colorectal cancer as an example of abnormal conditions. The procedure of a discrete differentiation process for obtained experimental data has been proposed as preliminary processing. Three information parameters have been selected to describe experimental data. Fischer F-statistics were used to determine the information content of the proposed information parameters. It has been proved that the proposed information parameters react on changing state of object under test and therefore can be effectively used for the abnormal condition detection
Synthesis, characterisation and physicochemical properties of hydrophobically modified inulin using long-chain fatty acyl chlorides
Get PDFA series of inulin derivatives were synthesized in aqueous solution using acyl chlorides with varying alkyl chain length (C10-C16). They were characterised using a number of techniques including MALDI TOF-MS, 1H NMR and FTIR and their degree of substitution determined. The solution properties of the hydrophobically modified inulins were investigated using dye solubilisation and surface tension and it was confirmed that the molecules aggregated in solution above a critical concentration (critical aggregation concentration, CAC). The value of the CAC was found to be reasonably consistent between the different techniques and was shown to decrease with increasing hydrophobe chain length. It was found that the C10, C12 and C14 derivatives formed stable oil-in-water emulsions and the emulsion droplet size decreased with increasing alkyl chain length. The C16 derivative was not able to produce stable oil-in-water emulsions; however, it was able to form stable water-in-oil emulsions. The fact that the derivatives are able to form micellar-like aggregates and stabilise emulsions makes them suitable candidates for the encapsulation and delivery of active compounds with potential application in food, cosmetic, personal care and pharmaceutical formulations
Insulation fault detection and localisation in electric and hybrid electric vehicles
Get PDFThis paper discusses a method for detection and localisation of the insulation faults in electrical equipment distributed along the body of electric and hybrid electric vehicles. At the beginning of the fault detection procedure it is required that the vehicle powertrain be shut-down. The method is based on measurement and comparison of leakage currents in every device in the electrical powertrain. The leakage currents are generated by a high voltage signal generator connected between the vehicle body ground and dc-bus wires and shifting the potential between the electrical equipment and chassis. The currents are measured using a current clamp to detect the active component of the leakage current corresponding to an insulation fault. The proposed method was implemented in a prototype device used to detect an insulation fault in subway powertrains (i.e. a metro train). The method demonstrated excellent efficiency through successful detection and localisation of insulation faults
Event-driven simulation of digital circuits using modified Petri nets algorithm
Get PDFThis paper presents a modified Petri nets simulation algorithm applied as an engine for a logic simulator in digital integrated circuit design. The simulator uses an event-driven algorithm and eliminates the delta delay which occurs in the majority of modern simulation algorithms. The algorithm has been tested for the logic simulation of combinational digital circuits and demonstrated more accurate simulation results. This has been achieved due to solving the issue of the priority choice problem when two or more events are occurring simultaneously
Simulating Auditory Hallucinations in a Video Game: Three Prototype Mechanisms
Get PDFIn previous work the authors have proposed the concept of 'ASC Simulation1: including audio-visual installations and experiences, as well as interactive video game systems, which simulate altered states of consciousness (ASCs) such as dreams and hallucinations. Building on the discussion of the authors' previous paper, where a large-scale qualitative study explored the changes to auditory perception that users of various intoxicating substances report, here the authors present three prototype audio mechanisms for simulating hallucinations in a video game. These were designed in the Unity video game engine as an early proof-of-concept. The first mechanism simulates 'selective auditory attention' to different sound sources, by attenuating the amplitude of unattended sources. The second simulates 'enhanced sounds', by adjusting perceived brightness through filtering. The third simulates 'spatial disruptions' to perception, by dislocating sound sources from their virtual acoustic origin in 3D-space, causing them to move in oscillations around a central location. In terms of programming structure, these mechanisms are designed using scripts that are attached to the collection of assets that make up the player character, and in future developments of this type of work we foresee a more advanced, standardised interface that models the senses, emotions and state of consciousness of player avatars
Religious affect and personal happiness: a replication among Sunni students in Malaysia
Get PDFBuilding on earlier studies conducted in Christian, Jewish, and Islamic contexts,
this study tests the hypothesis that higher levels of positive religious affect are associated
with higher levels of personal happiness among a sample of 189 Sunni
Muslim students studying at the International Islamic University in Malaysia; participants
completed the Sahin-Francis
Scale of Attitude toward Islam, the Oxford
Happiness Inventory, and the short-form
Eysenck Personality Questionnaire Revised.
The data reported a small but statistically significant association between
religiosity and happiness after taking sex and individual differences in personality
into account