Kind Of Hybrid System Research Articles

Hybrid Recommendation Using Temporal Data for Accuracy Improvement in Item Recommendation

Recommender systems have become a vital entity to the business world in form of software tools to make decisions. It estimates the overloaded information and provides the suitable decisions in any kind of business work through online. Especially in the area of e-commerce, recommender systems provide suggestions to users on the items that are likely based upon user’s true interest. Collaborative Filtering and Content Based Filtering are the main techniques of recommender systems. Collaborative Filtering is considered to be the best in all domains and always outperforms Content Based filtering. But, both the techniques have some limitations like data sparsity, cold start, gray sheep and scalability issues. To overcome these limitations, Hybrid Recommender Systems are used by combining Collaborative Filtering and Content Based Filtering. This paper proposes such kind of hybrid system by combining Collaborative Filtering and Content Based Filtering using time variance and machine learning algorithm.

Recent advances in hybrid system of porous silicon nanoparticles and biocompatible polymers for biomedical applications.

Hybrid systems of nanoparticles and polymers have emerged as a new material in the biomedical field. To date, various kinds of hybrid systems have been introduced and applied to drug delivery, regenerative medicine, therapeutics, disease diagnosis, and medical implantation. Among them, the hybridization of nanostructured porous silicon nanoparticles (pSiNPs) and biocompatible polymers has been highlighted due to its unique biological and physicochemical properties. This review focuses on the recent advances in the hybrid systems of pSiNPs and biocompatible polymers from an engineering aspect and its biomedical applications. Representative hybrid formulations, (i) Polymer-coated pSiNPs, (ii) pSiNPs-embedded polymeric nanofibers, are outlined along with their preparation methods, biomedical applications, and future perspectives. We believe this review provides insight into a new hybrid system of pSiNPs and biocompatible polymers as a promising nano-platform for further biomedical applications. Recently developedand representative hybrid systems of porous silicon nanoparticles and biocompatible polymers and their biomedical applications are introduced.

Performance analysis for hybrid PV/T system using low concentration MWCNT (water-based) nanofluid

This paper presents experimental work on utilising Nanofluid as a working agent for Photovoltaic Thermal Systems (PV/T). PV/T systems are one kind of hybrid systems in energy utilisation. They convert the incident solar radiation into two energy types; electricity and heat. In this research, experimental outdoor tests were directed to assess the execution of PV/T system that utilises water-based Multi Walls Carbon Nano Tubes “MWCNT” as a heat storage/heat absorption agent. The effect of varying Nanofluid volume concentration ratio was studied within the range (0%:0.3%) while fixing the circulation rate at 1.2 l/min. By analysing the experimental results, it can be noted that adding Nano Particles to the base fluid caused the thermal properties to have a significant increment leading the PV/T system to have a better thermal and electrical efficiency. The best system efficiencies were obtained at 0.075% V of MWCNTs – water based Nanofluid. At this concentration, a temperature reduction of 12 °C for the PV panel was attained at maximum incident radiation leading to an overall system efficiency of 83.26%. Also, an average temperature reduction of 10.3 °C was achieved over the daytime leading to an overall efficiency of 61.23%.

Hydraulic design and performance analysis on a small pump-turbine system for ocean renewable energy storage system

Korea has a myriad of islands in the south western coast that extensively rely on diesel generators for power production, which increase cost and environment pollution. The small hydro pump-turbine system for ocean renewable energy storage system is a kind of hybrid system that can reduce the usage of diesel generators and help to contribute to the environment in a positive manner by helping to reduce carbon emissions. The study focuses on initial hydraulic design and numerical analysis of a 30 kW-class pump-turbine system for energy independent islands in South Korea. The purpose of the study is to propose an ocean renewable energy storage system using a small pump-turbine system working with seawater. A 30 kW-class pump-turbine does not require a large head; approximately 30 m is sufficient for the design and application. Several other renewable energy systems like wind turbines, tidal turbines, wave energy converters and solar energy could be used to make a hybrid system with pump-turbine. The initial design achieved more than 85 % efficiency in both pump and turbine modes. However, further optimizations of the impeller blade shape and number of guide vane and stay vanes could improve the overall efficiency of the system.

Spin currents and filtering behavior in zigzag graphene nanoribbons with adsorbed molybdenum chains

By means of density-functional-theoretic calculations, we investigated the structural, electronic and transport properties of hydrogen-passivated zigzag graphene nanoribbons (ZGNRs) on which a one-atom-thick Mo chain was adsorbed (with or without one or two missing atoms), or in which the passivating hydrogen atoms were replaced by Mo atoms. Mo-passivated ZGNRs proved to be nonmagnetic. ZGNRs with an adsorbed defect-free Mo chain were most stable with the Mo atoms forming dimers above edge bay sites, which suppressed the magnetic moments of the C atoms in that half of the ribbon; around the Fermi level of these systems, each spin component had a transmission channel via the Mo spz band and one had an additional channel created by polarization of the ZGNR π* band, leading to a net spin current. The absence of an Mo dimer from an Mo chain adsorbed at the ZGNR edge made the system a perfect spin filter at low voltage bias by suppressing the Mo spz band channels. Thus this last kind of hybrid system is a potential spin valve.

Applications of Non-Thermal Plasma Technology in Methane Combustion

Applications of non-thermal plasma in methane catalysis combustion have attracted a lot of attentions in recent years due to its outstanding and unique properties. We summarized two kinds of hybrid systems of plasma and catalysts for methane combustion reaction and compared these two figurations. Results prove that combining non-thermal plasma and catalysts has an excellent performance for methane total oxidation compared with single ones.

Effect of plants and the combination of wetland treatment type systems on pathogen removal in tropical climate conditions

Although there are different treatment technologies to reduce water pollution, a few of them are efficient in pathogenic organism removal. Nowadays, near-nature systems like constructed wetlands (CWs) have been encouraged as alternative to remove this kind of organisms, due to their low operational and maintenance cost. The aim of this research was to evaluate different combinations (vertical and horizontal flow) of constructed wetlands as a possible technology for pathogen reduction under tropical climate (Colombia), as a result of the few research made about this kind of hybrid systems (train with vertical and horizontal systems) in tropical regions. The combination of vertical and horizontal subsurface flow CW showed the highest performance for the removal of total coliform, Escherichia coli (3log units and 4log units, respectively) and Helminth eggs (90%) allowing water reuse. Also for nitrogen reduction, this wetlands combination displayed the best results (more than 90%). Besides pathogen parameters, BOD5, COD, TSS were evaluated in the different experimental units and the results achieved a removal rate of >85% for all experimental units.

Simulation of Dynamic Response of Small Wind-Photovoltaic-Fuel Cell Hybrid Energy System

Renewable energy systems are of importance as being modular, nature-friendly and domestic. Among renewable energy systems, a great deal of research has been conducted especially on photovoltaic effect, wind energy and fuel cell in the recent years. This paper describes dynamic modeling and simulation results of a small wind-photovoltaic-fuel cell hybrid energy system. The hybrid system consists of a 500 W wind turbine, a photovoltaic, a proton exchange membrane fuel cell (PEMFC), ultracapacitors, an electrolyzer, a boost converter, controllers and a power converter that simulated using MATLAB solver. This kind of hybrid system is completely stand-alone, reliable and has high efficiency. In order to minimize sudden variations in voltage magnitude ultracapacitors are proposed. Power converter and inverter are used to produce ac output power. Dynamics of fuel-cell component such as double layer capacitance are also taken into account. Control scheme of fuel-cell flow controller and voltage regulators are based on PID controllers. Dynamic responses of the system for a step change in the electrical load and wind speed are presented. Results showed that the ability of the system in adapting itself to sudden changes and new conditions. Combination of PV and wind renewable sources is made the advantage of using this system in regions which have higher wind speeds in the seasons that suffers from less sunny days and vice versa.

Neuro-fuzzy integrated system with its different domain applications

Computational intelligence combines fuzzy systems, neural network and evolutionary computing. In this paper, architecture of a neuro–fuzzy integrated system is presented. A new kind of error backpropagation algorithm to adjust the membership functions of each variable and optimise fuzzy rules is developed. To minimise the output error, a variational method for determining globally optimal learning parameters and learning rules for online gradient descent training of multilayer neural network has been proposed. In order to show the effectiveness of the proposed system, simulation for different variety of domain has been performed. The controller for inverted pendulum has been demonstrated. The controller uses error backpropagation algorithm to adjust the membership functions of each variable, optimise fuzzy rules, and identify the inverted pendulum. Neuro–fuzzy integrated system for coronary heart disease has also been simulated. The results suggest that this kind of hybrid system is also suitable for the identification of patients with high/low cardiac risk.

Dynamical behavior of a hybrid system of nonhomogeneous timoshenko beam with partial non-collocated inputs

The dynamical behavior of a kind of elastic hybrid system is considered. This system consists of a nonhomogeneous Timoshenko beam linked at its boundary to a rigid body. The non-collocated input terms are required in the boundary feedback controls. It is proved that this closed loop system is well-posed. By a complete eigenfrequency analysis, it is shown that this infinite-dimensional hybrid system satisfies spectrum-determined growth condition. The stability of this system is discussed and some simulations are given to show that this kind of hybrid system can be exponentially stable under certain condition.

Prospects for hybrid MEG-MRI technology

Event Abstract Back to Event Prospects for hybrid MEG-MRI technology Risto Ilmoniemi1* 1 Aalto University , Department of Biomedical Engineering and Computational Science, Finland Magnetoencephalography (MEG) provides direct information about the brain’s neuronal currents through the measurement of femtotesla-level magnetic fields, enabling functional mapping with a 1-ms temporal accuracy. To correlate MEG findings with brain anatomy, structural imaging such as MRI is needed. However, in important clinical cases such as presurgical localization of eloquent cortex or the characterization of epileptic loci, proper combination of MEG and MRI data is hampered by the need to measure them with different devices at different times, which may cause localization errors of several milli¬meters. Ideally, one would like to measure both MEG and MRI with one instrument. The demonstration [1] that MRI can be performed at very low magnetic fields with SQUID magnetometers suggested that the two techniques could indeed be combined. The unification of MEG and MRI will constitute a new kind of hybrid system that would facilitate clinical diagnosis and presurgical mapping and help advance cognitive research of the brain. In addition, it would save costs and could be used when high-field MRI is not possible. The MEG-MRI hybrid system would allow simultaneity between MEG and MRI and would improve the spatial accuracy and the precision of quantitative measures of MEG functional imaging. Low-field MRI will improve patient safety and comfort (open structure, silent operation), provides superior T1 image contrast, and is free of susceptibility artefacts and other patient-specific geometric distortions. The feasibility of MEG-NMR, using SQUID sensors, has been demonstrated at the University of California at Berkeley, in Los Alamos, and in Berlin. In this talk, the prospects and challenges in building a hybrid MEG-MRI imaging system will be discussed and the European project MEGMRI will be described.

The techno-economic and environmental aspects of a hybrid PV-diesel-battery power system for remote farm houses

In this study, the solar radiation data of Balikesir in Turkey are analysed to assess the techno-economic viability and environmental performance of a hybrid Photovoltaic (PV)-diesel-battery system to meet the load requirements of a typical remote farm house. Several aspects of the system are studied through the Cost of Energy (CoE), the operational hours of diesel generator, unmet load, excess electricity generation, percentage of fuel savings, etc. The CoE for this kind of hybrid system is found to be 1.245 US$ /kWh. Simulations are performed for three cases (diesel only, PV-diesel and PV-diesel-battery). It is found that a diesel-only system produces 63 900 kWh of electricity and 69.7 tonnes of CO2, 13.0 kg of PM, 1.53 tonnes of NOx emissions per year. Using PV-diesel and PV-diesel-battery systems helps reduce the emissions for CO2 to 61.0 and 42.0 tonnes, for PM to 11.4 and 7.83 kg and for NOx to 1.34 and 0.92 tonnes, respectively. The diesel-only system is more economical if the fuel price remains below US$2/L. Otherwise, PV-diesel and PV-diesel-battery systems become more cost-effective. Also, the environmental impact improvement factor is found as 0.127 and 0.399 for CO2, 0.123 and 0.397 for PM and 0.124 and 0.398 for NOx for both PV-diesel and PV-diesel-battery systems, respectively.

Hierarchical control of combined hybrid electric vehicle

This paper describes a novel strategy developed for optimising the energy flow in a combined hybrid electric vehicle (CHEV) structure. This method implemented an online energy management by a hierarchical hybrid controller between dual sources in this kind of hybrid systems. This structure included two energy sources, the battery and the stack of fuel cells, and its power train system is based on an electric motor (EM) and internal combustion engine (ICE) in a parallel combination. The proposed control method involves a supervisory controller which in the first layer captures all the possible operation modes. In the second layer, an advanced fuzzy hybrid controller has been developed for each of the defined modes. Finally in the third layer of controller, there are local controllers to regulate the set points of each subsystem to reach the best performance and acceptable operation indexes. The simulation results confirm the feasibility and encourage more research toward an actual application.

A hybrid system of manufacturing resource planning and just-in-time manufacturing

The need to solve production management problems in Chinese manufacturing enterprises results in developing and implementing a hybrid system of manufacturing resource planning (MRP II) and just-in-time manufacturing (JIT). This article gives an overview of some basic concepts in this area, including a classification of manufacturing modes and three kinds of hybrid systems. The authors analyze the feature of these hybrid systems and discuss a practical example in a machine tool manufacturing enterprise.